1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2016, The Linux Foundation. All rights reserved.
4 */
5#include <linux/clk.h>
6#include <linux/slab.h>
7#include <linux/bitops.h>
8#include <linux/dma-mapping.h>
9#include <linux/dmaengine.h>
10#include <linux/module.h>
11#include <linux/mtd/rawnand.h>
12#include <linux/mtd/partitions.h>
13#include <linux/of.h>
14#include <linux/of_device.h>
15#include <linux/delay.h>
16#include <linux/dma/qcom_bam_dma.h>
17
18/* NANDc reg offsets */
19#define	NAND_FLASH_CMD			0x00
20#define	NAND_ADDR0			0x04
21#define	NAND_ADDR1			0x08
22#define	NAND_FLASH_CHIP_SELECT		0x0c
23#define	NAND_EXEC_CMD			0x10
24#define	NAND_FLASH_STATUS		0x14
25#define	NAND_BUFFER_STATUS		0x18
26#define	NAND_DEV0_CFG0			0x20
27#define	NAND_DEV0_CFG1			0x24
28#define	NAND_DEV0_ECC_CFG		0x28
29#define	NAND_DEV1_ECC_CFG		0x2c
30#define	NAND_DEV1_CFG0			0x30
31#define	NAND_DEV1_CFG1			0x34
32#define	NAND_READ_ID			0x40
33#define	NAND_READ_STATUS		0x44
34#define	NAND_DEV_CMD0			0xa0
35#define	NAND_DEV_CMD1			0xa4
36#define	NAND_DEV_CMD2			0xa8
37#define	NAND_DEV_CMD_VLD		0xac
38#define	SFLASHC_BURST_CFG		0xe0
39#define	NAND_ERASED_CW_DETECT_CFG	0xe8
40#define	NAND_ERASED_CW_DETECT_STATUS	0xec
41#define	NAND_EBI2_ECC_BUF_CFG		0xf0
42#define	FLASH_BUF_ACC			0x100
43
44#define	NAND_CTRL			0xf00
45#define	NAND_VERSION			0xf08
46#define	NAND_READ_LOCATION_0		0xf20
47#define	NAND_READ_LOCATION_1		0xf24
48#define	NAND_READ_LOCATION_2		0xf28
49#define	NAND_READ_LOCATION_3		0xf2c
50
51/* dummy register offsets, used by write_reg_dma */
52#define	NAND_DEV_CMD1_RESTORE		0xdead
53#define	NAND_DEV_CMD_VLD_RESTORE	0xbeef
54
55/* NAND_FLASH_CMD bits */
56#define	PAGE_ACC			BIT(4)
57#define	LAST_PAGE			BIT(5)
58
59/* NAND_FLASH_CHIP_SELECT bits */
60#define	NAND_DEV_SEL			0
61#define	DM_EN				BIT(2)
62
63/* NAND_FLASH_STATUS bits */
64#define	FS_OP_ERR			BIT(4)
65#define	FS_READY_BSY_N			BIT(5)
66#define	FS_MPU_ERR			BIT(8)
67#define	FS_DEVICE_STS_ERR		BIT(16)
68#define	FS_DEVICE_WP			BIT(23)
69
70/* NAND_BUFFER_STATUS bits */
71#define	BS_UNCORRECTABLE_BIT		BIT(8)
72#define	BS_CORRECTABLE_ERR_MSK		0x1f
73
74/* NAND_DEVn_CFG0 bits */
75#define	DISABLE_STATUS_AFTER_WRITE	4
76#define	CW_PER_PAGE			6
77#define	UD_SIZE_BYTES			9
78#define	ECC_PARITY_SIZE_BYTES_RS	19
79#define	SPARE_SIZE_BYTES		23
80#define	NUM_ADDR_CYCLES			27
81#define	STATUS_BFR_READ			30
82#define	SET_RD_MODE_AFTER_STATUS	31
83
84/* NAND_DEVn_CFG0 bits */
85#define	DEV0_CFG1_ECC_DISABLE		0
86#define	WIDE_FLASH			1
87#define	NAND_RECOVERY_CYCLES		2
88#define	CS_ACTIVE_BSY			5
89#define	BAD_BLOCK_BYTE_NUM		6
90#define	BAD_BLOCK_IN_SPARE_AREA		16
91#define	WR_RD_BSY_GAP			17
92#define	ENABLE_BCH_ECC			27
93
94/* NAND_DEV0_ECC_CFG bits */
95#define	ECC_CFG_ECC_DISABLE		0
96#define	ECC_SW_RESET			1
97#define	ECC_MODE			4
98#define	ECC_PARITY_SIZE_BYTES_BCH	8
99#define	ECC_NUM_DATA_BYTES		16
100#define	ECC_FORCE_CLK_OPEN		30
101
102/* NAND_DEV_CMD1 bits */
103#define	READ_ADDR			0
104
105/* NAND_DEV_CMD_VLD bits */
106#define	READ_START_VLD			BIT(0)
107#define	READ_STOP_VLD			BIT(1)
108#define	WRITE_START_VLD			BIT(2)
109#define	ERASE_START_VLD			BIT(3)
110#define	SEQ_READ_START_VLD		BIT(4)
111
112/* NAND_EBI2_ECC_BUF_CFG bits */
113#define	NUM_STEPS			0
114
115/* NAND_ERASED_CW_DETECT_CFG bits */
116#define	ERASED_CW_ECC_MASK		1
117#define	AUTO_DETECT_RES			0
118#define	MASK_ECC			(1 << ERASED_CW_ECC_MASK)
119#define	RESET_ERASED_DET		(1 << AUTO_DETECT_RES)
120#define	ACTIVE_ERASED_DET		(0 << AUTO_DETECT_RES)
121#define	CLR_ERASED_PAGE_DET		(RESET_ERASED_DET | MASK_ECC)
122#define	SET_ERASED_PAGE_DET		(ACTIVE_ERASED_DET | MASK_ECC)
123
124/* NAND_ERASED_CW_DETECT_STATUS bits */
125#define	PAGE_ALL_ERASED			BIT(7)
126#define	CODEWORD_ALL_ERASED		BIT(6)
127#define	PAGE_ERASED			BIT(5)
128#define	CODEWORD_ERASED			BIT(4)
129#define	ERASED_PAGE			(PAGE_ALL_ERASED | PAGE_ERASED)
130#define	ERASED_CW			(CODEWORD_ALL_ERASED | CODEWORD_ERASED)
131
132/* NAND_READ_LOCATION_n bits */
133#define READ_LOCATION_OFFSET		0
134#define READ_LOCATION_SIZE		16
135#define READ_LOCATION_LAST		31
136
137/* Version Mask */
138#define	NAND_VERSION_MAJOR_MASK		0xf0000000
139#define	NAND_VERSION_MAJOR_SHIFT	28
140#define	NAND_VERSION_MINOR_MASK		0x0fff0000
141#define	NAND_VERSION_MINOR_SHIFT	16
142
143/* NAND OP_CMDs */
144#define	OP_PAGE_READ			0x2
145#define	OP_PAGE_READ_WITH_ECC		0x3
146#define	OP_PAGE_READ_WITH_ECC_SPARE	0x4
147#define	OP_PROGRAM_PAGE			0x6
148#define	OP_PAGE_PROGRAM_WITH_ECC	0x7
149#define	OP_PROGRAM_PAGE_SPARE		0x9
150#define	OP_BLOCK_ERASE			0xa
151#define	OP_FETCH_ID			0xb
152#define	OP_RESET_DEVICE			0xd
153
154/* Default Value for NAND_DEV_CMD_VLD */
155#define NAND_DEV_CMD_VLD_VAL		(READ_START_VLD | WRITE_START_VLD | \
156					 ERASE_START_VLD | SEQ_READ_START_VLD)
157
158/* NAND_CTRL bits */
159#define	BAM_MODE_EN			BIT(0)
160
161/*
162 * the NAND controller performs reads/writes with ECC in 516 byte chunks.
163 * the driver calls the chunks 'step' or 'codeword' interchangeably
164 */
165#define	NANDC_STEP_SIZE			512
166
167/*
168 * the largest page size we support is 8K, this will have 16 steps/codewords
169 * of 512 bytes each
170 */
171#define	MAX_NUM_STEPS			(SZ_8K / NANDC_STEP_SIZE)
172
173/* we read at most 3 registers per codeword scan */
174#define	MAX_REG_RD			(3 * MAX_NUM_STEPS)
175
176/* ECC modes supported by the controller */
177#define	ECC_NONE	BIT(0)
178#define	ECC_RS_4BIT	BIT(1)
179#define	ECC_BCH_4BIT	BIT(2)
180#define	ECC_BCH_8BIT	BIT(3)
181
182#define nandc_set_read_loc(nandc, reg, offset, size, is_last)	\
183nandc_set_reg(nandc, NAND_READ_LOCATION_##reg,			\
184	      ((offset) << READ_LOCATION_OFFSET) |		\
185	      ((size) << READ_LOCATION_SIZE) |			\
186	      ((is_last) << READ_LOCATION_LAST))
187
188/*
189 * Returns the actual register address for all NAND_DEV_ registers
190 * (i.e. NAND_DEV_CMD0, NAND_DEV_CMD1, NAND_DEV_CMD2 and NAND_DEV_CMD_VLD)
191 */
192#define dev_cmd_reg_addr(nandc, reg) ((nandc)->props->dev_cmd_reg_start + (reg))
193
194/* Returns the NAND register physical address */
195#define nandc_reg_phys(chip, offset) ((chip)->base_phys + (offset))
196
197/* Returns the dma address for reg read buffer */
198#define reg_buf_dma_addr(chip, vaddr) \
199	((chip)->reg_read_dma + \
200	((uint8_t *)(vaddr) - (uint8_t *)(chip)->reg_read_buf))
201
202#define QPIC_PER_CW_CMD_ELEMENTS	32
203#define QPIC_PER_CW_CMD_SGL		32
204#define QPIC_PER_CW_DATA_SGL		8
205
206#define QPIC_NAND_COMPLETION_TIMEOUT	msecs_to_jiffies(2000)
207
208/*
209 * Flags used in DMA descriptor preparation helper functions
210 * (i.e. read_reg_dma/write_reg_dma/read_data_dma/write_data_dma)
211 */
212/* Don't set the EOT in current tx BAM sgl */
213#define NAND_BAM_NO_EOT			BIT(0)
214/* Set the NWD flag in current BAM sgl */
215#define NAND_BAM_NWD			BIT(1)
216/* Finish writing in the current BAM sgl and start writing in another BAM sgl */
217#define NAND_BAM_NEXT_SGL		BIT(2)
218/*
219 * Erased codeword status is being used two times in single transfer so this
220 * flag will determine the current value of erased codeword status register
221 */
222#define NAND_ERASED_CW_SET		BIT(4)
223
224/*
225 * This data type corresponds to the BAM transaction which will be used for all
226 * NAND transfers.
227 * @bam_ce - the array of BAM command elements
228 * @cmd_sgl - sgl for NAND BAM command pipe
229 * @data_sgl - sgl for NAND BAM consumer/producer pipe
230 * @bam_ce_pos - the index in bam_ce which is available for next sgl
231 * @bam_ce_start - the index in bam_ce which marks the start position ce
232 *		   for current sgl. It will be used for size calculation
233 *		   for current sgl
234 * @cmd_sgl_pos - current index in command sgl.
235 * @cmd_sgl_start - start index in command sgl.
236 * @tx_sgl_pos - current index in data sgl for tx.
237 * @tx_sgl_start - start index in data sgl for tx.
238 * @rx_sgl_pos - current index in data sgl for rx.
239 * @rx_sgl_start - start index in data sgl for rx.
240 * @wait_second_completion - wait for second DMA desc completion before making
241 *			     the NAND transfer completion.
242 * @txn_done - completion for NAND transfer.
243 * @last_data_desc - last DMA desc in data channel (tx/rx).
244 * @last_cmd_desc - last DMA desc in command channel.
245 */
246struct bam_transaction {
247	struct bam_cmd_element *bam_ce;
248	struct scatterlist *cmd_sgl;
249	struct scatterlist *data_sgl;
250	u32 bam_ce_pos;
251	u32 bam_ce_start;
252	u32 cmd_sgl_pos;
253	u32 cmd_sgl_start;
254	u32 tx_sgl_pos;
255	u32 tx_sgl_start;
256	u32 rx_sgl_pos;
257	u32 rx_sgl_start;
258	bool wait_second_completion;
259	struct completion txn_done;
260	struct dma_async_tx_descriptor *last_data_desc;
261	struct dma_async_tx_descriptor *last_cmd_desc;
262};
263
264/*
265 * This data type corresponds to the nand dma descriptor
266 * @list - list for desc_info
267 * @dir - DMA transfer direction
268 * @adm_sgl - sgl which will be used for single sgl dma descriptor. Only used by
269 *	      ADM
270 * @bam_sgl - sgl which will be used for dma descriptor. Only used by BAM
271 * @sgl_cnt - number of SGL in bam_sgl. Only used by BAM
272 * @dma_desc - low level DMA engine descriptor
273 */
274struct desc_info {
275	struct list_head node;
276
277	enum dma_data_direction dir;
278	union {
279		struct scatterlist adm_sgl;
280		struct {
281			struct scatterlist *bam_sgl;
282			int sgl_cnt;
283		};
284	};
285	struct dma_async_tx_descriptor *dma_desc;
286};
287
288/*
289 * holds the current register values that we want to write. acts as a contiguous
290 * chunk of memory which we use to write the controller registers through DMA.
291 */
292struct nandc_regs {
293	__le32 cmd;
294	__le32 addr0;
295	__le32 addr1;
296	__le32 chip_sel;
297	__le32 exec;
298
299	__le32 cfg0;
300	__le32 cfg1;
301	__le32 ecc_bch_cfg;
302
303	__le32 clrflashstatus;
304	__le32 clrreadstatus;
305
306	__le32 cmd1;
307	__le32 vld;
308
309	__le32 orig_cmd1;
310	__le32 orig_vld;
311
312	__le32 ecc_buf_cfg;
313	__le32 read_location0;
314	__le32 read_location1;
315	__le32 read_location2;
316	__le32 read_location3;
317
318	__le32 erased_cw_detect_cfg_clr;
319	__le32 erased_cw_detect_cfg_set;
320};
321
322/*
323 * NAND controller data struct
324 *
325 * @controller:			base controller structure
326 * @host_list:			list containing all the chips attached to the
327 *				controller
328 * @dev:			parent device
329 * @base:			MMIO base
330 * @base_phys:			physical base address of controller registers
331 * @base_dma:			dma base address of controller registers
332 * @core_clk:			controller clock
333 * @aon_clk:			another controller clock
334 *
335 * @chan:			dma channel
336 * @cmd_crci:			ADM DMA CRCI for command flow control
337 * @data_crci:			ADM DMA CRCI for data flow control
338 * @desc_list:			DMA descriptor list (list of desc_infos)
339 *
340 * @data_buffer:		our local DMA buffer for page read/writes,
341 *				used when we can't use the buffer provided
342 *				by upper layers directly
343 * @buf_size/count/start:	markers for chip->legacy.read_buf/write_buf
344 *				functions
345 * @reg_read_buf:		local buffer for reading back registers via DMA
346 * @reg_read_dma:		contains dma address for register read buffer
347 * @reg_read_pos:		marker for data read in reg_read_buf
348 *
349 * @regs:			a contiguous chunk of memory for DMA register
350 *				writes. contains the register values to be
351 *				written to controller
352 * @cmd1/vld:			some fixed controller register values
353 * @props:			properties of current NAND controller,
354 *				initialized via DT match data
355 * @max_cwperpage:		maximum QPIC codewords required. calculated
356 *				from all connected NAND devices pagesize
357 */
358struct qcom_nand_controller {
359	struct nand_controller controller;
360	struct list_head host_list;
361
362	struct device *dev;
363
364	void __iomem *base;
365	phys_addr_t base_phys;
366	dma_addr_t base_dma;
367
368	struct clk *core_clk;
369	struct clk *aon_clk;
370
371	union {
372		/* will be used only by QPIC for BAM DMA */
373		struct {
374			struct dma_chan *tx_chan;
375			struct dma_chan *rx_chan;
376			struct dma_chan *cmd_chan;
377		};
378
379		/* will be used only by EBI2 for ADM DMA */
380		struct {
381			struct dma_chan *chan;
382			unsigned int cmd_crci;
383			unsigned int data_crci;
384		};
385	};
386
387	struct list_head desc_list;
388	struct bam_transaction *bam_txn;
389
390	u8		*data_buffer;
391	int		buf_size;
392	int		buf_count;
393	int		buf_start;
394	unsigned int	max_cwperpage;
395
396	__le32 *reg_read_buf;
397	dma_addr_t reg_read_dma;
398	int reg_read_pos;
399
400	struct nandc_regs *regs;
401
402	u32 cmd1, vld;
403	const struct qcom_nandc_props *props;
404};
405
406/*
407 * NAND chip structure
408 *
409 * @chip:			base NAND chip structure
410 * @node:			list node to add itself to host_list in
411 *				qcom_nand_controller
412 *
413 * @cs:				chip select value for this chip
414 * @cw_size:			the number of bytes in a single step/codeword
415 *				of a page, consisting of all data, ecc, spare
416 *				and reserved bytes
417 * @cw_data:			the number of bytes within a codeword protected
418 *				by ECC
419 * @use_ecc:			request the controller to use ECC for the
420 *				upcoming read/write
421 * @bch_enabled:		flag to tell whether BCH ECC mode is used
422 * @ecc_bytes_hw:		ECC bytes used by controller hardware for this
423 *				chip
424 * @status:			value to be returned if NAND_CMD_STATUS command
425 *				is executed
426 * @last_command:		keeps track of last command on this chip. used
427 *				for reading correct status
428 *
429 * @cfg0, cfg1, cfg0_raw..:	NANDc register configurations needed for
430 *				ecc/non-ecc mode for the current nand flash
431 *				device
432 */
433struct qcom_nand_host {
434	struct nand_chip chip;
435	struct list_head node;
436
437	int cs;
438	int cw_size;
439	int cw_data;
440	bool use_ecc;
441	bool bch_enabled;
442	int ecc_bytes_hw;
443	int spare_bytes;
444	int bbm_size;
445	u8 status;
446	int last_command;
447
448	u32 cfg0, cfg1;
449	u32 cfg0_raw, cfg1_raw;
450	u32 ecc_buf_cfg;
451	u32 ecc_bch_cfg;
452	u32 clrflashstatus;
453	u32 clrreadstatus;
454};
455
456/*
457 * This data type corresponds to the NAND controller properties which varies
458 * among different NAND controllers.
459 * @ecc_modes - ecc mode for NAND
460 * @is_bam - whether NAND controller is using BAM
461 * @is_qpic - whether NAND CTRL is part of qpic IP
462 * @dev_cmd_reg_start - NAND_DEV_CMD_* registers starting offset
463 */
464struct qcom_nandc_props {
465	u32 ecc_modes;
466	bool is_bam;
467	bool is_qpic;
468	u32 dev_cmd_reg_start;
469};
470
471/* Frees the BAM transaction memory */
472static void free_bam_transaction(struct qcom_nand_controller *nandc)
473{
474	struct bam_transaction *bam_txn = nandc->bam_txn;
475
476	devm_kfree(nandc->dev, bam_txn);
477}
478
479/* Allocates and Initializes the BAM transaction */
480static struct bam_transaction *
481alloc_bam_transaction(struct qcom_nand_controller *nandc)
482{
483	struct bam_transaction *bam_txn;
484	size_t bam_txn_size;
485	unsigned int num_cw = nandc->max_cwperpage;
486	void *bam_txn_buf;
487
488	bam_txn_size =
489		sizeof(*bam_txn) + num_cw *
490		((sizeof(*bam_txn->bam_ce) * QPIC_PER_CW_CMD_ELEMENTS) +
491		(sizeof(*bam_txn->cmd_sgl) * QPIC_PER_CW_CMD_SGL) +
492		(sizeof(*bam_txn->data_sgl) * QPIC_PER_CW_DATA_SGL));
493
494	bam_txn_buf = devm_kzalloc(nandc->dev, bam_txn_size, GFP_KERNEL);
495	if (!bam_txn_buf)
496		return NULL;
497
498	bam_txn = bam_txn_buf;
499	bam_txn_buf += sizeof(*bam_txn);
500
501	bam_txn->bam_ce = bam_txn_buf;
502	bam_txn_buf +=
503		sizeof(*bam_txn->bam_ce) * QPIC_PER_CW_CMD_ELEMENTS * num_cw;
504
505	bam_txn->cmd_sgl = bam_txn_buf;
506	bam_txn_buf +=
507		sizeof(*bam_txn->cmd_sgl) * QPIC_PER_CW_CMD_SGL * num_cw;
508
509	bam_txn->data_sgl = bam_txn_buf;
510
511	init_completion(&bam_txn->txn_done);
512
513	return bam_txn;
514}
515
516/* Clears the BAM transaction indexes */
517static void clear_bam_transaction(struct qcom_nand_controller *nandc)
518{
519	struct bam_transaction *bam_txn = nandc->bam_txn;
520
521	if (!nandc->props->is_bam)
522		return;
523
524	bam_txn->bam_ce_pos = 0;
525	bam_txn->bam_ce_start = 0;
526	bam_txn->cmd_sgl_pos = 0;
527	bam_txn->cmd_sgl_start = 0;
528	bam_txn->tx_sgl_pos = 0;
529	bam_txn->tx_sgl_start = 0;
530	bam_txn->rx_sgl_pos = 0;
531	bam_txn->rx_sgl_start = 0;
532	bam_txn->last_data_desc = NULL;
533	bam_txn->wait_second_completion = false;
534
535	sg_init_table(bam_txn->cmd_sgl, nandc->max_cwperpage *
536		      QPIC_PER_CW_CMD_SGL);
537	sg_init_table(bam_txn->data_sgl, nandc->max_cwperpage *
538		      QPIC_PER_CW_DATA_SGL);
539
540	reinit_completion(&bam_txn->txn_done);
541}
542
543/* Callback for DMA descriptor completion */
544static void qpic_bam_dma_done(void *data)
545{
546	struct bam_transaction *bam_txn = data;
547
548	/*
549	 * In case of data transfer with NAND, 2 callbacks will be generated.
550	 * One for command channel and another one for data channel.
551	 * If current transaction has data descriptors
552	 * (i.e. wait_second_completion is true), then set this to false
553	 * and wait for second DMA descriptor completion.
554	 */
555	if (bam_txn->wait_second_completion)
556		bam_txn->wait_second_completion = false;
557	else
558		complete(&bam_txn->txn_done);
559}
560
561static inline struct qcom_nand_host *to_qcom_nand_host(struct nand_chip *chip)
562{
563	return container_of(chip, struct qcom_nand_host, chip);
564}
565
566static inline struct qcom_nand_controller *
567get_qcom_nand_controller(struct nand_chip *chip)
568{
569	return container_of(chip->controller, struct qcom_nand_controller,
570			    controller);
571}
572
573static inline u32 nandc_read(struct qcom_nand_controller *nandc, int offset)
574{
575	return ioread32(nandc->base + offset);
576}
577
578static inline void nandc_write(struct qcom_nand_controller *nandc, int offset,
579			       u32 val)
580{
581	iowrite32(val, nandc->base + offset);
582}
583
584static inline void nandc_read_buffer_sync(struct qcom_nand_controller *nandc,
585					  bool is_cpu)
586{
587	if (!nandc->props->is_bam)
588		return;
589
590	if (is_cpu)
591		dma_sync_single_for_cpu(nandc->dev, nandc->reg_read_dma,
592					MAX_REG_RD *
593					sizeof(*nandc->reg_read_buf),
594					DMA_FROM_DEVICE);
595	else
596		dma_sync_single_for_device(nandc->dev, nandc->reg_read_dma,
597					   MAX_REG_RD *
598					   sizeof(*nandc->reg_read_buf),
599					   DMA_FROM_DEVICE);
600}
601
602static __le32 *offset_to_nandc_reg(struct nandc_regs *regs, int offset)
603{
604	switch (offset) {
605	case NAND_FLASH_CMD:
606		return &regs->cmd;
607	case NAND_ADDR0:
608		return &regs->addr0;
609	case NAND_ADDR1:
610		return &regs->addr1;
611	case NAND_FLASH_CHIP_SELECT:
612		return &regs->chip_sel;
613	case NAND_EXEC_CMD:
614		return &regs->exec;
615	case NAND_FLASH_STATUS:
616		return &regs->clrflashstatus;
617	case NAND_DEV0_CFG0:
618		return &regs->cfg0;
619	case NAND_DEV0_CFG1:
620		return &regs->cfg1;
621	case NAND_DEV0_ECC_CFG:
622		return &regs->ecc_bch_cfg;
623	case NAND_READ_STATUS:
624		return &regs->clrreadstatus;
625	case NAND_DEV_CMD1:
626		return &regs->cmd1;
627	case NAND_DEV_CMD1_RESTORE:
628		return &regs->orig_cmd1;
629	case NAND_DEV_CMD_VLD:
630		return &regs->vld;
631	case NAND_DEV_CMD_VLD_RESTORE:
632		return &regs->orig_vld;
633	case NAND_EBI2_ECC_BUF_CFG:
634		return &regs->ecc_buf_cfg;
635	case NAND_READ_LOCATION_0:
636		return &regs->read_location0;
637	case NAND_READ_LOCATION_1:
638		return &regs->read_location1;
639	case NAND_READ_LOCATION_2:
640		return &regs->read_location2;
641	case NAND_READ_LOCATION_3:
642		return &regs->read_location3;
643	default:
644		return NULL;
645	}
646}
647
648static void nandc_set_reg(struct qcom_nand_controller *nandc, int offset,
649			  u32 val)
650{
651	struct nandc_regs *regs = nandc->regs;
652	__le32 *reg;
653
654	reg = offset_to_nandc_reg(regs, offset);
655
656	if (reg)
657		*reg = cpu_to_le32(val);
658}
659
660/* helper to configure address register values */
661static void set_address(struct qcom_nand_host *host, u16 column, int page)
662{
663	struct nand_chip *chip = &host->chip;
664	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
665
666	if (chip->options & NAND_BUSWIDTH_16)
667		column >>= 1;
668
669	nandc_set_reg(nandc, NAND_ADDR0, page << 16 | column);
670	nandc_set_reg(nandc, NAND_ADDR1, page >> 16 & 0xff);
671}
672
673/*
674 * update_rw_regs:	set up read/write register values, these will be
675 *			written to the NAND controller registers via DMA
676 *
677 * @num_cw:		number of steps for the read/write operation
678 * @read:		read or write operation
679 */
680static void update_rw_regs(struct qcom_nand_host *host, int num_cw, bool read)
681{
682	struct nand_chip *chip = &host->chip;
683	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
684	u32 cmd, cfg0, cfg1, ecc_bch_cfg;
685
686	if (read) {
687		if (host->use_ecc)
688			cmd = OP_PAGE_READ_WITH_ECC | PAGE_ACC | LAST_PAGE;
689		else
690			cmd = OP_PAGE_READ | PAGE_ACC | LAST_PAGE;
691	} else {
692		cmd = OP_PROGRAM_PAGE | PAGE_ACC | LAST_PAGE;
693	}
694
695	if (host->use_ecc) {
696		cfg0 = (host->cfg0 & ~(7U << CW_PER_PAGE)) |
697				(num_cw - 1) << CW_PER_PAGE;
698
699		cfg1 = host->cfg1;
700		ecc_bch_cfg = host->ecc_bch_cfg;
701	} else {
702		cfg0 = (host->cfg0_raw & ~(7U << CW_PER_PAGE)) |
703				(num_cw - 1) << CW_PER_PAGE;
704
705		cfg1 = host->cfg1_raw;
706		ecc_bch_cfg = 1 << ECC_CFG_ECC_DISABLE;
707	}
708
709	nandc_set_reg(nandc, NAND_FLASH_CMD, cmd);
710	nandc_set_reg(nandc, NAND_DEV0_CFG0, cfg0);
711	nandc_set_reg(nandc, NAND_DEV0_CFG1, cfg1);
712	nandc_set_reg(nandc, NAND_DEV0_ECC_CFG, ecc_bch_cfg);
713	nandc_set_reg(nandc, NAND_EBI2_ECC_BUF_CFG, host->ecc_buf_cfg);
714	nandc_set_reg(nandc, NAND_FLASH_STATUS, host->clrflashstatus);
715	nandc_set_reg(nandc, NAND_READ_STATUS, host->clrreadstatus);
716	nandc_set_reg(nandc, NAND_EXEC_CMD, 1);
717
718	if (read)
719		nandc_set_read_loc(nandc, 0, 0, host->use_ecc ?
720				   host->cw_data : host->cw_size, 1);
721}
722
723/*
724 * Maps the scatter gather list for DMA transfer and forms the DMA descriptor
725 * for BAM. This descriptor will be added in the NAND DMA descriptor queue
726 * which will be submitted to DMA engine.
727 */
728static int prepare_bam_async_desc(struct qcom_nand_controller *nandc,
729				  struct dma_chan *chan,
730				  unsigned long flags)
731{
732	struct desc_info *desc;
733	struct scatterlist *sgl;
734	unsigned int sgl_cnt;
735	int ret;
736	struct bam_transaction *bam_txn = nandc->bam_txn;
737	enum dma_transfer_direction dir_eng;
738	struct dma_async_tx_descriptor *dma_desc;
739
740	desc = kzalloc(sizeof(*desc), GFP_KERNEL);
741	if (!desc)
742		return -ENOMEM;
743
744	if (chan == nandc->cmd_chan) {
745		sgl = &bam_txn->cmd_sgl[bam_txn->cmd_sgl_start];
746		sgl_cnt = bam_txn->cmd_sgl_pos - bam_txn->cmd_sgl_start;
747		bam_txn->cmd_sgl_start = bam_txn->cmd_sgl_pos;
748		dir_eng = DMA_MEM_TO_DEV;
749		desc->dir = DMA_TO_DEVICE;
750	} else if (chan == nandc->tx_chan) {
751		sgl = &bam_txn->data_sgl[bam_txn->tx_sgl_start];
752		sgl_cnt = bam_txn->tx_sgl_pos - bam_txn->tx_sgl_start;
753		bam_txn->tx_sgl_start = bam_txn->tx_sgl_pos;
754		dir_eng = DMA_MEM_TO_DEV;
755		desc->dir = DMA_TO_DEVICE;
756	} else {
757		sgl = &bam_txn->data_sgl[bam_txn->rx_sgl_start];
758		sgl_cnt = bam_txn->rx_sgl_pos - bam_txn->rx_sgl_start;
759		bam_txn->rx_sgl_start = bam_txn->rx_sgl_pos;
760		dir_eng = DMA_DEV_TO_MEM;
761		desc->dir = DMA_FROM_DEVICE;
762	}
763
764	sg_mark_end(sgl + sgl_cnt - 1);
765	ret = dma_map_sg(nandc->dev, sgl, sgl_cnt, desc->dir);
766	if (ret == 0) {
767		dev_err(nandc->dev, "failure in mapping desc\n");
768		kfree(desc);
769		return -ENOMEM;
770	}
771
772	desc->sgl_cnt = sgl_cnt;
773	desc->bam_sgl = sgl;
774
775	dma_desc = dmaengine_prep_slave_sg(chan, sgl, sgl_cnt, dir_eng,
776					   flags);
777
778	if (!dma_desc) {
779		dev_err(nandc->dev, "failure in prep desc\n");
780		dma_unmap_sg(nandc->dev, sgl, sgl_cnt, desc->dir);
781		kfree(desc);
782		return -EINVAL;
783	}
784
785	desc->dma_desc = dma_desc;
786
787	/* update last data/command descriptor */
788	if (chan == nandc->cmd_chan)
789		bam_txn->last_cmd_desc = dma_desc;
790	else
791		bam_txn->last_data_desc = dma_desc;
792
793	list_add_tail(&desc->node, &nandc->desc_list);
794
795	return 0;
796}
797
798/*
799 * Prepares the command descriptor for BAM DMA which will be used for NAND
800 * register reads and writes. The command descriptor requires the command
801 * to be formed in command element type so this function uses the command
802 * element from bam transaction ce array and fills the same with required
803 * data. A single SGL can contain multiple command elements so
804 * NAND_BAM_NEXT_SGL will be used for starting the separate SGL
805 * after the current command element.
806 */
807static int prep_bam_dma_desc_cmd(struct qcom_nand_controller *nandc, bool read,
808				 int reg_off, const void *vaddr,
809				 int size, unsigned int flags)
810{
811	int bam_ce_size;
812	int i, ret;
813	struct bam_cmd_element *bam_ce_buffer;
814	struct bam_transaction *bam_txn = nandc->bam_txn;
815
816	bam_ce_buffer = &bam_txn->bam_ce[bam_txn->bam_ce_pos];
817
818	/* fill the command desc */
819	for (i = 0; i < size; i++) {
820		if (read)
821			bam_prep_ce(&bam_ce_buffer[i],
822				    nandc_reg_phys(nandc, reg_off + 4 * i),
823				    BAM_READ_COMMAND,
824				    reg_buf_dma_addr(nandc,
825						     (__le32 *)vaddr + i));
826		else
827			bam_prep_ce_le32(&bam_ce_buffer[i],
828					 nandc_reg_phys(nandc, reg_off + 4 * i),
829					 BAM_WRITE_COMMAND,
830					 *((__le32 *)vaddr + i));
831	}
832
833	bam_txn->bam_ce_pos += size;
834
835	/* use the separate sgl after this command */
836	if (flags & NAND_BAM_NEXT_SGL) {
837		bam_ce_buffer = &bam_txn->bam_ce[bam_txn->bam_ce_start];
838		bam_ce_size = (bam_txn->bam_ce_pos -
839				bam_txn->bam_ce_start) *
840				sizeof(struct bam_cmd_element);
841		sg_set_buf(&bam_txn->cmd_sgl[bam_txn->cmd_sgl_pos],
842			   bam_ce_buffer, bam_ce_size);
843		bam_txn->cmd_sgl_pos++;
844		bam_txn->bam_ce_start = bam_txn->bam_ce_pos;
845
846		if (flags & NAND_BAM_NWD) {
847			ret = prepare_bam_async_desc(nandc, nandc->cmd_chan,
848						     DMA_PREP_FENCE |
849						     DMA_PREP_CMD);
850			if (ret)
851				return ret;
852		}
853	}
854
855	return 0;
856}
857
858/*
859 * Prepares the data descriptor for BAM DMA which will be used for NAND
860 * data reads and writes.
861 */
862static int prep_bam_dma_desc_data(struct qcom_nand_controller *nandc, bool read,
863				  const void *vaddr,
864				  int size, unsigned int flags)
865{
866	int ret;
867	struct bam_transaction *bam_txn = nandc->bam_txn;
868
869	if (read) {
870		sg_set_buf(&bam_txn->data_sgl[bam_txn->rx_sgl_pos],
871			   vaddr, size);
872		bam_txn->rx_sgl_pos++;
873	} else {
874		sg_set_buf(&bam_txn->data_sgl[bam_txn->tx_sgl_pos],
875			   vaddr, size);
876		bam_txn->tx_sgl_pos++;
877
878		/*
879		 * BAM will only set EOT for DMA_PREP_INTERRUPT so if this flag
880		 * is not set, form the DMA descriptor
881		 */
882		if (!(flags & NAND_BAM_NO_EOT)) {
883			ret = prepare_bam_async_desc(nandc, nandc->tx_chan,
884						     DMA_PREP_INTERRUPT);
885			if (ret)
886				return ret;
887		}
888	}
889
890	return 0;
891}
892
893static int prep_adm_dma_desc(struct qcom_nand_controller *nandc, bool read,
894			     int reg_off, const void *vaddr, int size,
895			     bool flow_control)
896{
897	struct desc_info *desc;
898	struct dma_async_tx_descriptor *dma_desc;
899	struct scatterlist *sgl;
900	struct dma_slave_config slave_conf;
901	enum dma_transfer_direction dir_eng;
902	int ret;
903
904	desc = kzalloc(sizeof(*desc), GFP_KERNEL);
905	if (!desc)
906		return -ENOMEM;
907
908	sgl = &desc->adm_sgl;
909
910	sg_init_one(sgl, vaddr, size);
911
912	if (read) {
913		dir_eng = DMA_DEV_TO_MEM;
914		desc->dir = DMA_FROM_DEVICE;
915	} else {
916		dir_eng = DMA_MEM_TO_DEV;
917		desc->dir = DMA_TO_DEVICE;
918	}
919
920	ret = dma_map_sg(nandc->dev, sgl, 1, desc->dir);
921	if (ret == 0) {
922		ret = -ENOMEM;
923		goto err;
924	}
925
926	memset(&slave_conf, 0x00, sizeof(slave_conf));
927
928	slave_conf.device_fc = flow_control;
929	if (read) {
930		slave_conf.src_maxburst = 16;
931		slave_conf.src_addr = nandc->base_dma + reg_off;
932		slave_conf.slave_id = nandc->data_crci;
933	} else {
934		slave_conf.dst_maxburst = 16;
935		slave_conf.dst_addr = nandc->base_dma + reg_off;
936		slave_conf.slave_id = nandc->cmd_crci;
937	}
938
939	ret = dmaengine_slave_config(nandc->chan, &slave_conf);
940	if (ret) {
941		dev_err(nandc->dev, "failed to configure dma channel\n");
942		goto err;
943	}
944
945	dma_desc = dmaengine_prep_slave_sg(nandc->chan, sgl, 1, dir_eng, 0);
946	if (!dma_desc) {
947		dev_err(nandc->dev, "failed to prepare desc\n");
948		ret = -EINVAL;
949		goto err;
950	}
951
952	desc->dma_desc = dma_desc;
953
954	list_add_tail(&desc->node, &nandc->desc_list);
955
956	return 0;
957err:
958	kfree(desc);
959
960	return ret;
961}
962
963/*
964 * read_reg_dma:	prepares a descriptor to read a given number of
965 *			contiguous registers to the reg_read_buf pointer
966 *
967 * @first:		offset of the first register in the contiguous block
968 * @num_regs:		number of registers to read
969 * @flags:		flags to control DMA descriptor preparation
970 */
971static int read_reg_dma(struct qcom_nand_controller *nandc, int first,
972			int num_regs, unsigned int flags)
973{
974	bool flow_control = false;
975	void *vaddr;
976
977	vaddr = nandc->reg_read_buf + nandc->reg_read_pos;
978	nandc->reg_read_pos += num_regs;
979
980	if (first == NAND_DEV_CMD_VLD || first == NAND_DEV_CMD1)
981		first = dev_cmd_reg_addr(nandc, first);
982
983	if (nandc->props->is_bam)
984		return prep_bam_dma_desc_cmd(nandc, true, first, vaddr,
985					     num_regs, flags);
986
987	if (first == NAND_READ_ID || first == NAND_FLASH_STATUS)
988		flow_control = true;
989
990	return prep_adm_dma_desc(nandc, true, first, vaddr,
991				 num_regs * sizeof(u32), flow_control);
992}
993
994/*
995 * write_reg_dma:	prepares a descriptor to write a given number of
996 *			contiguous registers
997 *
998 * @first:		offset of the first register in the contiguous block
999 * @num_regs:		number of registers to write
1000 * @flags:		flags to control DMA descriptor preparation
1001 */
1002static int write_reg_dma(struct qcom_nand_controller *nandc, int first,
1003			 int num_regs, unsigned int flags)
1004{
1005	bool flow_control = false;
1006	struct nandc_regs *regs = nandc->regs;
1007	void *vaddr;
1008
1009	vaddr = offset_to_nandc_reg(regs, first);
1010
1011	if (first == NAND_ERASED_CW_DETECT_CFG) {
1012		if (flags & NAND_ERASED_CW_SET)
1013			vaddr = &regs->erased_cw_detect_cfg_set;
1014		else
1015			vaddr = &regs->erased_cw_detect_cfg_clr;
1016	}
1017
1018	if (first == NAND_EXEC_CMD)
1019		flags |= NAND_BAM_NWD;
1020
1021	if (first == NAND_DEV_CMD1_RESTORE || first == NAND_DEV_CMD1)
1022		first = dev_cmd_reg_addr(nandc, NAND_DEV_CMD1);
1023
1024	if (first == NAND_DEV_CMD_VLD_RESTORE || first == NAND_DEV_CMD_VLD)
1025		first = dev_cmd_reg_addr(nandc, NAND_DEV_CMD_VLD);
1026
1027	if (nandc->props->is_bam)
1028		return prep_bam_dma_desc_cmd(nandc, false, first, vaddr,
1029					     num_regs, flags);
1030
1031	if (first == NAND_FLASH_CMD)
1032		flow_control = true;
1033
1034	return prep_adm_dma_desc(nandc, false, first, vaddr,
1035				 num_regs * sizeof(u32), flow_control);
1036}
1037
1038/*
1039 * read_data_dma:	prepares a DMA descriptor to transfer data from the
1040 *			controller's internal buffer to the buffer 'vaddr'
1041 *
1042 * @reg_off:		offset within the controller's data buffer
1043 * @vaddr:		virtual address of the buffer we want to write to
1044 * @size:		DMA transaction size in bytes
1045 * @flags:		flags to control DMA descriptor preparation
1046 */
1047static int read_data_dma(struct qcom_nand_controller *nandc, int reg_off,
1048			 const u8 *vaddr, int size, unsigned int flags)
1049{
1050	if (nandc->props->is_bam)
1051		return prep_bam_dma_desc_data(nandc, true, vaddr, size, flags);
1052
1053	return prep_adm_dma_desc(nandc, true, reg_off, vaddr, size, false);
1054}
1055
1056/*
1057 * write_data_dma:	prepares a DMA descriptor to transfer data from
1058 *			'vaddr' to the controller's internal buffer
1059 *
1060 * @reg_off:		offset within the controller's data buffer
1061 * @vaddr:		virtual address of the buffer we want to read from
1062 * @size:		DMA transaction size in bytes
1063 * @flags:		flags to control DMA descriptor preparation
1064 */
1065static int write_data_dma(struct qcom_nand_controller *nandc, int reg_off,
1066			  const u8 *vaddr, int size, unsigned int flags)
1067{
1068	if (nandc->props->is_bam)
1069		return prep_bam_dma_desc_data(nandc, false, vaddr, size, flags);
1070
1071	return prep_adm_dma_desc(nandc, false, reg_off, vaddr, size, false);
1072}
1073
1074/*
1075 * Helper to prepare DMA descriptors for configuring registers
1076 * before reading a NAND page.
1077 */
1078static void config_nand_page_read(struct qcom_nand_controller *nandc)
1079{
1080	write_reg_dma(nandc, NAND_ADDR0, 2, 0);
1081	write_reg_dma(nandc, NAND_DEV0_CFG0, 3, 0);
1082	write_reg_dma(nandc, NAND_EBI2_ECC_BUF_CFG, 1, 0);
1083	write_reg_dma(nandc, NAND_ERASED_CW_DETECT_CFG, 1, 0);
1084	write_reg_dma(nandc, NAND_ERASED_CW_DETECT_CFG, 1,
1085		      NAND_ERASED_CW_SET | NAND_BAM_NEXT_SGL);
1086}
1087
1088/*
1089 * Helper to prepare DMA descriptors for configuring registers
1090 * before reading each codeword in NAND page.
1091 */
1092static void
1093config_nand_cw_read(struct qcom_nand_controller *nandc, bool use_ecc)
1094{
1095	if (nandc->props->is_bam)
1096		write_reg_dma(nandc, NAND_READ_LOCATION_0, 4,
1097			      NAND_BAM_NEXT_SGL);
1098
1099	write_reg_dma(nandc, NAND_FLASH_CMD, 1, NAND_BAM_NEXT_SGL);
1100	write_reg_dma(nandc, NAND_EXEC_CMD, 1, NAND_BAM_NEXT_SGL);
1101
1102	if (use_ecc) {
1103		read_reg_dma(nandc, NAND_FLASH_STATUS, 2, 0);
1104		read_reg_dma(nandc, NAND_ERASED_CW_DETECT_STATUS, 1,
1105			     NAND_BAM_NEXT_SGL);
1106	} else {
1107		read_reg_dma(nandc, NAND_FLASH_STATUS, 1, NAND_BAM_NEXT_SGL);
1108	}
1109}
1110
1111/*
1112 * Helper to prepare dma descriptors to configure registers needed for reading a
1113 * single codeword in page
1114 */
1115static void
1116config_nand_single_cw_page_read(struct qcom_nand_controller *nandc,
1117				bool use_ecc)
1118{
1119	config_nand_page_read(nandc);
1120	config_nand_cw_read(nandc, use_ecc);
1121}
1122
1123/*
1124 * Helper to prepare DMA descriptors used to configure registers needed for
1125 * before writing a NAND page.
1126 */
1127static void config_nand_page_write(struct qcom_nand_controller *nandc)
1128{
1129	write_reg_dma(nandc, NAND_ADDR0, 2, 0);
1130	write_reg_dma(nandc, NAND_DEV0_CFG0, 3, 0);
1131	write_reg_dma(nandc, NAND_EBI2_ECC_BUF_CFG, 1,
1132		      NAND_BAM_NEXT_SGL);
1133}
1134
1135/*
1136 * Helper to prepare DMA descriptors for configuring registers
1137 * before writing each codeword in NAND page.
1138 */
1139static void config_nand_cw_write(struct qcom_nand_controller *nandc)
1140{
1141	write_reg_dma(nandc, NAND_FLASH_CMD, 1, NAND_BAM_NEXT_SGL);
1142	write_reg_dma(nandc, NAND_EXEC_CMD, 1, NAND_BAM_NEXT_SGL);
1143
1144	read_reg_dma(nandc, NAND_FLASH_STATUS, 1, NAND_BAM_NEXT_SGL);
1145
1146	write_reg_dma(nandc, NAND_FLASH_STATUS, 1, 0);
1147	write_reg_dma(nandc, NAND_READ_STATUS, 1, NAND_BAM_NEXT_SGL);
1148}
1149
1150/*
1151 * the following functions are used within chip->legacy.cmdfunc() to
1152 * perform different NAND_CMD_* commands
1153 */
1154
1155/* sets up descriptors for NAND_CMD_PARAM */
1156static int nandc_param(struct qcom_nand_host *host)
1157{
1158	struct nand_chip *chip = &host->chip;
1159	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
1160
1161	/*
1162	 * NAND_CMD_PARAM is called before we know much about the FLASH chip
1163	 * in use. we configure the controller to perform a raw read of 512
1164	 * bytes to read onfi params
1165	 */
1166	nandc_set_reg(nandc, NAND_FLASH_CMD, OP_PAGE_READ | PAGE_ACC | LAST_PAGE);
1167	nandc_set_reg(nandc, NAND_ADDR0, 0);
1168	nandc_set_reg(nandc, NAND_ADDR1, 0);
1169	nandc_set_reg(nandc, NAND_DEV0_CFG0, 0 << CW_PER_PAGE
1170					| 512 << UD_SIZE_BYTES
1171					| 5 << NUM_ADDR_CYCLES
1172					| 0 << SPARE_SIZE_BYTES);
1173	nandc_set_reg(nandc, NAND_DEV0_CFG1, 7 << NAND_RECOVERY_CYCLES
1174					| 0 << CS_ACTIVE_BSY
1175					| 17 << BAD_BLOCK_BYTE_NUM
1176					| 1 << BAD_BLOCK_IN_SPARE_AREA
1177					| 2 << WR_RD_BSY_GAP
1178					| 0 << WIDE_FLASH
1179					| 1 << DEV0_CFG1_ECC_DISABLE);
1180	nandc_set_reg(nandc, NAND_EBI2_ECC_BUF_CFG, 1 << ECC_CFG_ECC_DISABLE);
1181
1182	/* configure CMD1 and VLD for ONFI param probing */
1183	nandc_set_reg(nandc, NAND_DEV_CMD_VLD,
1184		      (nandc->vld & ~READ_START_VLD));
1185	nandc_set_reg(nandc, NAND_DEV_CMD1,
1186		      (nandc->cmd1 & ~(0xFF << READ_ADDR))
1187		      | NAND_CMD_PARAM << READ_ADDR);
1188
1189	nandc_set_reg(nandc, NAND_EXEC_CMD, 1);
1190
1191	nandc_set_reg(nandc, NAND_DEV_CMD1_RESTORE, nandc->cmd1);
1192	nandc_set_reg(nandc, NAND_DEV_CMD_VLD_RESTORE, nandc->vld);
1193	nandc_set_read_loc(nandc, 0, 0, 512, 1);
1194
1195	write_reg_dma(nandc, NAND_DEV_CMD_VLD, 1, 0);
1196	write_reg_dma(nandc, NAND_DEV_CMD1, 1, NAND_BAM_NEXT_SGL);
1197
1198	nandc->buf_count = 512;
1199	memset(nandc->data_buffer, 0xff, nandc->buf_count);
1200
1201	config_nand_single_cw_page_read(nandc, false);
1202
1203	read_data_dma(nandc, FLASH_BUF_ACC, nandc->data_buffer,
1204		      nandc->buf_count, 0);
1205
1206	/* restore CMD1 and VLD regs */
1207	write_reg_dma(nandc, NAND_DEV_CMD1_RESTORE, 1, 0);
1208	write_reg_dma(nandc, NAND_DEV_CMD_VLD_RESTORE, 1, NAND_BAM_NEXT_SGL);
1209
1210	return 0;
1211}
1212
1213/* sets up descriptors for NAND_CMD_ERASE1 */
1214static int erase_block(struct qcom_nand_host *host, int page_addr)
1215{
1216	struct nand_chip *chip = &host->chip;
1217	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
1218
1219	nandc_set_reg(nandc, NAND_FLASH_CMD,
1220		      OP_BLOCK_ERASE | PAGE_ACC | LAST_PAGE);
1221	nandc_set_reg(nandc, NAND_ADDR0, page_addr);
1222	nandc_set_reg(nandc, NAND_ADDR1, 0);
1223	nandc_set_reg(nandc, NAND_DEV0_CFG0,
1224		      host->cfg0_raw & ~(7 << CW_PER_PAGE));
1225	nandc_set_reg(nandc, NAND_DEV0_CFG1, host->cfg1_raw);
1226	nandc_set_reg(nandc, NAND_EXEC_CMD, 1);
1227	nandc_set_reg(nandc, NAND_FLASH_STATUS, host->clrflashstatus);
1228	nandc_set_reg(nandc, NAND_READ_STATUS, host->clrreadstatus);
1229
1230	write_reg_dma(nandc, NAND_FLASH_CMD, 3, NAND_BAM_NEXT_SGL);
1231	write_reg_dma(nandc, NAND_DEV0_CFG0, 2, NAND_BAM_NEXT_SGL);
1232	write_reg_dma(nandc, NAND_EXEC_CMD, 1, NAND_BAM_NEXT_SGL);
1233
1234	read_reg_dma(nandc, NAND_FLASH_STATUS, 1, NAND_BAM_NEXT_SGL);
1235
1236	write_reg_dma(nandc, NAND_FLASH_STATUS, 1, 0);
1237	write_reg_dma(nandc, NAND_READ_STATUS, 1, NAND_BAM_NEXT_SGL);
1238
1239	return 0;
1240}
1241
1242/* sets up descriptors for NAND_CMD_READID */
1243static int read_id(struct qcom_nand_host *host, int column)
1244{
1245	struct nand_chip *chip = &host->chip;
1246	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
1247
1248	if (column == -1)
1249		return 0;
1250
1251	nandc_set_reg(nandc, NAND_FLASH_CMD, OP_FETCH_ID);
1252	nandc_set_reg(nandc, NAND_ADDR0, column);
1253	nandc_set_reg(nandc, NAND_ADDR1, 0);
1254	nandc_set_reg(nandc, NAND_FLASH_CHIP_SELECT,
1255		      nandc->props->is_bam ? 0 : DM_EN);
1256	nandc_set_reg(nandc, NAND_EXEC_CMD, 1);
1257
1258	write_reg_dma(nandc, NAND_FLASH_CMD, 4, NAND_BAM_NEXT_SGL);
1259	write_reg_dma(nandc, NAND_EXEC_CMD, 1, NAND_BAM_NEXT_SGL);
1260
1261	read_reg_dma(nandc, NAND_READ_ID, 1, NAND_BAM_NEXT_SGL);
1262
1263	return 0;
1264}
1265
1266/* sets up descriptors for NAND_CMD_RESET */
1267static int reset(struct qcom_nand_host *host)
1268{
1269	struct nand_chip *chip = &host->chip;
1270	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
1271
1272	nandc_set_reg(nandc, NAND_FLASH_CMD, OP_RESET_DEVICE);
1273	nandc_set_reg(nandc, NAND_EXEC_CMD, 1);
1274
1275	write_reg_dma(nandc, NAND_FLASH_CMD, 1, NAND_BAM_NEXT_SGL);
1276	write_reg_dma(nandc, NAND_EXEC_CMD, 1, NAND_BAM_NEXT_SGL);
1277
1278	read_reg_dma(nandc, NAND_FLASH_STATUS, 1, NAND_BAM_NEXT_SGL);
1279
1280	return 0;
1281}
1282
1283/* helpers to submit/free our list of dma descriptors */
1284static int submit_descs(struct qcom_nand_controller *nandc)
1285{
1286	struct desc_info *desc;
1287	dma_cookie_t cookie = 0;
1288	struct bam_transaction *bam_txn = nandc->bam_txn;
1289	int r;
1290
1291	if (nandc->props->is_bam) {
1292		if (bam_txn->rx_sgl_pos > bam_txn->rx_sgl_start) {
1293			r = prepare_bam_async_desc(nandc, nandc->rx_chan, 0);
1294			if (r)
1295				return r;
1296		}
1297
1298		if (bam_txn->tx_sgl_pos > bam_txn->tx_sgl_start) {
1299			r = prepare_bam_async_desc(nandc, nandc->tx_chan,
1300						   DMA_PREP_INTERRUPT);
1301			if (r)
1302				return r;
1303		}
1304
1305		if (bam_txn->cmd_sgl_pos > bam_txn->cmd_sgl_start) {
1306			r = prepare_bam_async_desc(nandc, nandc->cmd_chan,
1307						   DMA_PREP_CMD);
1308			if (r)
1309				return r;
1310		}
1311	}
1312
1313	list_for_each_entry(desc, &nandc->desc_list, node)
1314		cookie = dmaengine_submit(desc->dma_desc);
1315
1316	if (nandc->props->is_bam) {
1317		bam_txn->last_cmd_desc->callback = qpic_bam_dma_done;
1318		bam_txn->last_cmd_desc->callback_param = bam_txn;
1319		if (bam_txn->last_data_desc) {
1320			bam_txn->last_data_desc->callback = qpic_bam_dma_done;
1321			bam_txn->last_data_desc->callback_param = bam_txn;
1322			bam_txn->wait_second_completion = true;
1323		}
1324
1325		dma_async_issue_pending(nandc->tx_chan);
1326		dma_async_issue_pending(nandc->rx_chan);
1327		dma_async_issue_pending(nandc->cmd_chan);
1328
1329		if (!wait_for_completion_timeout(&bam_txn->txn_done,
1330						 QPIC_NAND_COMPLETION_TIMEOUT))
1331			return -ETIMEDOUT;
1332	} else {
1333		if (dma_sync_wait(nandc->chan, cookie) != DMA_COMPLETE)
1334			return -ETIMEDOUT;
1335	}
1336
1337	return 0;
1338}
1339
1340static void free_descs(struct qcom_nand_controller *nandc)
1341{
1342	struct desc_info *desc, *n;
1343
1344	list_for_each_entry_safe(desc, n, &nandc->desc_list, node) {
1345		list_del(&desc->node);
1346
1347		if (nandc->props->is_bam)
1348			dma_unmap_sg(nandc->dev, desc->bam_sgl,
1349				     desc->sgl_cnt, desc->dir);
1350		else
1351			dma_unmap_sg(nandc->dev, &desc->adm_sgl, 1,
1352				     desc->dir);
1353
1354		kfree(desc);
1355	}
1356}
1357
1358/* reset the register read buffer for next NAND operation */
1359static void clear_read_regs(struct qcom_nand_controller *nandc)
1360{
1361	nandc->reg_read_pos = 0;
1362	nandc_read_buffer_sync(nandc, false);
1363}
1364
1365static void pre_command(struct qcom_nand_host *host, int command)
1366{
1367	struct nand_chip *chip = &host->chip;
1368	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
1369
1370	nandc->buf_count = 0;
1371	nandc->buf_start = 0;
1372	host->use_ecc = false;
1373	host->last_command = command;
1374
1375	clear_read_regs(nandc);
1376
1377	if (command == NAND_CMD_RESET || command == NAND_CMD_READID ||
1378	    command == NAND_CMD_PARAM || command == NAND_CMD_ERASE1)
1379		clear_bam_transaction(nandc);
1380}
1381
1382/*
1383 * this is called after NAND_CMD_PAGEPROG and NAND_CMD_ERASE1 to set our
1384 * privately maintained status byte, this status byte can be read after
1385 * NAND_CMD_STATUS is called
1386 */
1387static void parse_erase_write_errors(struct qcom_nand_host *host, int command)
1388{
1389	struct nand_chip *chip = &host->chip;
1390	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
1391	struct nand_ecc_ctrl *ecc = &chip->ecc;
1392	int num_cw;
1393	int i;
1394
1395	num_cw = command == NAND_CMD_PAGEPROG ? ecc->steps : 1;
1396	nandc_read_buffer_sync(nandc, true);
1397
1398	for (i = 0; i < num_cw; i++) {
1399		u32 flash_status = le32_to_cpu(nandc->reg_read_buf[i]);
1400
1401		if (flash_status & FS_MPU_ERR)
1402			host->status &= ~NAND_STATUS_WP;
1403
1404		if (flash_status & FS_OP_ERR || (i == (num_cw - 1) &&
1405						 (flash_status &
1406						  FS_DEVICE_STS_ERR)))
1407			host->status |= NAND_STATUS_FAIL;
1408	}
1409}
1410
1411static void post_command(struct qcom_nand_host *host, int command)
1412{
1413	struct nand_chip *chip = &host->chip;
1414	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
1415
1416	switch (command) {
1417	case NAND_CMD_READID:
1418		nandc_read_buffer_sync(nandc, true);
1419		memcpy(nandc->data_buffer, nandc->reg_read_buf,
1420		       nandc->buf_count);
1421		break;
1422	case NAND_CMD_PAGEPROG:
1423	case NAND_CMD_ERASE1:
1424		parse_erase_write_errors(host, command);
1425		break;
1426	default:
1427		break;
1428	}
1429}
1430
1431/*
1432 * Implements chip->legacy.cmdfunc. It's  only used for a limited set of
1433 * commands. The rest of the commands wouldn't be called by upper layers.
1434 * For example, NAND_CMD_READOOB would never be called because we have our own
1435 * versions of read_oob ops for nand_ecc_ctrl.
1436 */
1437static void qcom_nandc_command(struct nand_chip *chip, unsigned int command,
1438			       int column, int page_addr)
1439{
1440	struct qcom_nand_host *host = to_qcom_nand_host(chip);
1441	struct nand_ecc_ctrl *ecc = &chip->ecc;
1442	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
1443	bool wait = false;
1444	int ret = 0;
1445
1446	pre_command(host, command);
1447
1448	switch (command) {
1449	case NAND_CMD_RESET:
1450		ret = reset(host);
1451		wait = true;
1452		break;
1453
1454	case NAND_CMD_READID:
1455		nandc->buf_count = 4;
1456		ret = read_id(host, column);
1457		wait = true;
1458		break;
1459
1460	case NAND_CMD_PARAM:
1461		ret = nandc_param(host);
1462		wait = true;
1463		break;
1464
1465	case NAND_CMD_ERASE1:
1466		ret = erase_block(host, page_addr);
1467		wait = true;
1468		break;
1469
1470	case NAND_CMD_READ0:
1471		/* we read the entire page for now */
1472		WARN_ON(column != 0);
1473
1474		host->use_ecc = true;
1475		set_address(host, 0, page_addr);
1476		update_rw_regs(host, ecc->steps, true);
1477		break;
1478
1479	case NAND_CMD_SEQIN:
1480		WARN_ON(column != 0);
1481		set_address(host, 0, page_addr);
1482		break;
1483
1484	case NAND_CMD_PAGEPROG:
1485	case NAND_CMD_STATUS:
1486	case NAND_CMD_NONE:
1487	default:
1488		break;
1489	}
1490
1491	if (ret) {
1492		dev_err(nandc->dev, "failure executing command %d\n",
1493			command);
1494		free_descs(nandc);
1495		return;
1496	}
1497
1498	if (wait) {
1499		ret = submit_descs(nandc);
1500		if (ret)
1501			dev_err(nandc->dev,
1502				"failure submitting descs for command %d\n",
1503				command);
1504	}
1505
1506	free_descs(nandc);
1507
1508	post_command(host, command);
1509}
1510
1511/*
1512 * when using BCH ECC, the HW flags an error in NAND_FLASH_STATUS if it read
1513 * an erased CW, and reports an erased CW in NAND_ERASED_CW_DETECT_STATUS.
1514 *
1515 * when using RS ECC, the HW reports the same erros when reading an erased CW,
1516 * but it notifies that it is an erased CW by placing special characters at
1517 * certain offsets in the buffer.
1518 *
1519 * verify if the page is erased or not, and fix up the page for RS ECC by
1520 * replacing the special characters with 0xff.
1521 */
1522static bool erased_chunk_check_and_fixup(u8 *data_buf, int data_len)
1523{
1524	u8 empty1, empty2;
1525
1526	/*
1527	 * an erased page flags an error in NAND_FLASH_STATUS, check if the page
1528	 * is erased by looking for 0x54s at offsets 3 and 175 from the
1529	 * beginning of each codeword
1530	 */
1531
1532	empty1 = data_buf[3];
1533	empty2 = data_buf[175];
1534
1535	/*
1536	 * if the erased codework markers, if they exist override them with
1537	 * 0xffs
1538	 */
1539	if ((empty1 == 0x54 && empty2 == 0xff) ||
1540	    (empty1 == 0xff && empty2 == 0x54)) {
1541		data_buf[3] = 0xff;
1542		data_buf[175] = 0xff;
1543	}
1544
1545	/*
1546	 * check if the entire chunk contains 0xffs or not. if it doesn't, then
1547	 * restore the original values at the special offsets
1548	 */
1549	if (memchr_inv(data_buf, 0xff, data_len)) {
1550		data_buf[3] = empty1;
1551		data_buf[175] = empty2;
1552
1553		return false;
1554	}
1555
1556	return true;
1557}
1558
1559struct read_stats {
1560	__le32 flash;
1561	__le32 buffer;
1562	__le32 erased_cw;
1563};
1564
1565/* reads back FLASH_STATUS register set by the controller */
1566static int check_flash_errors(struct qcom_nand_host *host, int cw_cnt)
1567{
1568	struct nand_chip *chip = &host->chip;
1569	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
1570	int i;
1571
1572	nandc_read_buffer_sync(nandc, true);
1573
1574	for (i = 0; i < cw_cnt; i++) {
1575		u32 flash = le32_to_cpu(nandc->reg_read_buf[i]);
1576
1577		if (flash & (FS_OP_ERR | FS_MPU_ERR))
1578			return -EIO;
1579	}
1580
1581	return 0;
1582}
1583
1584/* performs raw read for one codeword */
1585static int
1586qcom_nandc_read_cw_raw(struct mtd_info *mtd, struct nand_chip *chip,
1587		       u8 *data_buf, u8 *oob_buf, int page, int cw)
1588{
1589	struct qcom_nand_host *host = to_qcom_nand_host(chip);
1590	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
1591	struct nand_ecc_ctrl *ecc = &chip->ecc;
1592	int data_size1, data_size2, oob_size1, oob_size2;
1593	int ret, reg_off = FLASH_BUF_ACC, read_loc = 0;
1594
1595	nand_read_page_op(chip, page, 0, NULL, 0);
1596	host->use_ecc = false;
1597
1598	clear_bam_transaction(nandc);
1599	set_address(host, host->cw_size * cw, page);
1600	update_rw_regs(host, 1, true);
1601	config_nand_page_read(nandc);
1602
1603	data_size1 = mtd->writesize - host->cw_size * (ecc->steps - 1);
1604	oob_size1 = host->bbm_size;
1605
1606	if (cw == (ecc->steps - 1)) {
1607		data_size2 = ecc->size - data_size1 -
1608			     ((ecc->steps - 1) * 4);
1609		oob_size2 = (ecc->steps * 4) + host->ecc_bytes_hw +
1610			    host->spare_bytes;
1611	} else {
1612		data_size2 = host->cw_data - data_size1;
1613		oob_size2 = host->ecc_bytes_hw + host->spare_bytes;
1614	}
1615
1616	if (nandc->props->is_bam) {
1617		nandc_set_read_loc(nandc, 0, read_loc, data_size1, 0);
1618		read_loc += data_size1;
1619
1620		nandc_set_read_loc(nandc, 1, read_loc, oob_size1, 0);
1621		read_loc += oob_size1;
1622
1623		nandc_set_read_loc(nandc, 2, read_loc, data_size2, 0);
1624		read_loc += data_size2;
1625
1626		nandc_set_read_loc(nandc, 3, read_loc, oob_size2, 1);
1627	}
1628
1629	config_nand_cw_read(nandc, false);
1630
1631	read_data_dma(nandc, reg_off, data_buf, data_size1, 0);
1632	reg_off += data_size1;
1633
1634	read_data_dma(nandc, reg_off, oob_buf, oob_size1, 0);
1635	reg_off += oob_size1;
1636
1637	read_data_dma(nandc, reg_off, data_buf + data_size1, data_size2, 0);
1638	reg_off += data_size2;
1639
1640	read_data_dma(nandc, reg_off, oob_buf + oob_size1, oob_size2, 0);
1641
1642	ret = submit_descs(nandc);
1643	free_descs(nandc);
1644	if (ret) {
1645		dev_err(nandc->dev, "failure to read raw cw %d\n", cw);
1646		return ret;
1647	}
1648
1649	return check_flash_errors(host, 1);
1650}
1651
1652/*
1653 * Bitflips can happen in erased codewords also so this function counts the
1654 * number of 0 in each CW for which ECC engine returns the uncorrectable
1655 * error. The page will be assumed as erased if this count is less than or
1656 * equal to the ecc->strength for each CW.
1657 *
1658 * 1. Both DATA and OOB need to be checked for number of 0. The
1659 *    top-level API can be called with only data buf or OOB buf so use
1660 *    chip->data_buf if data buf is null and chip->oob_poi if oob buf
1661 *    is null for copying the raw bytes.
1662 * 2. Perform raw read for all the CW which has uncorrectable errors.
1663 * 3. For each CW, check the number of 0 in cw_data and usable OOB bytes.
1664 *    The BBM and spare bytes bit flip won’t affect the ECC so don’t check
1665 *    the number of bitflips in this area.
1666 */
1667static int
1668check_for_erased_page(struct qcom_nand_host *host, u8 *data_buf,
1669		      u8 *oob_buf, unsigned long uncorrectable_cws,
1670		      int page, unsigned int max_bitflips)
1671{
1672	struct nand_chip *chip = &host->chip;
1673	struct mtd_info *mtd = nand_to_mtd(chip);
1674	struct nand_ecc_ctrl *ecc = &chip->ecc;
1675	u8 *cw_data_buf, *cw_oob_buf;
1676	int cw, data_size, oob_size, ret = 0;
1677
1678	if (!data_buf)
1679		data_buf = nand_get_data_buf(chip);
1680
1681	if (!oob_buf) {
1682		nand_get_data_buf(chip);
1683		oob_buf = chip->oob_poi;
1684	}
1685
1686	for_each_set_bit(cw, &uncorrectable_cws, ecc->steps) {
1687		if (cw == (ecc->steps - 1)) {
1688			data_size = ecc->size - ((ecc->steps - 1) * 4);
1689			oob_size = (ecc->steps * 4) + host->ecc_bytes_hw;
1690		} else {
1691			data_size = host->cw_data;
1692			oob_size = host->ecc_bytes_hw;
1693		}
1694
1695		/* determine starting buffer address for current CW */
1696		cw_data_buf = data_buf + (cw * host->cw_data);
1697		cw_oob_buf = oob_buf + (cw * ecc->bytes);
1698
1699		ret = qcom_nandc_read_cw_raw(mtd, chip, cw_data_buf,
1700					     cw_oob_buf, page, cw);
1701		if (ret)
1702			return ret;
1703
1704		/*
1705		 * make sure it isn't an erased page reported
1706		 * as not-erased by HW because of a few bitflips
1707		 */
1708		ret = nand_check_erased_ecc_chunk(cw_data_buf, data_size,
1709						  cw_oob_buf + host->bbm_size,
1710						  oob_size, NULL,
1711						  0, ecc->strength);
1712		if (ret < 0) {
1713			mtd->ecc_stats.failed++;
1714		} else {
1715			mtd->ecc_stats.corrected += ret;
1716			max_bitflips = max_t(unsigned int, max_bitflips, ret);
1717		}
1718	}
1719
1720	return max_bitflips;
1721}
1722
1723/*
1724 * reads back status registers set by the controller to notify page read
1725 * errors. this is equivalent to what 'ecc->correct()' would do.
1726 */
1727static int parse_read_errors(struct qcom_nand_host *host, u8 *data_buf,
1728			     u8 *oob_buf, int page)
1729{
1730	struct nand_chip *chip = &host->chip;
1731	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
1732	struct mtd_info *mtd = nand_to_mtd(chip);
1733	struct nand_ecc_ctrl *ecc = &chip->ecc;
1734	unsigned int max_bitflips = 0, uncorrectable_cws = 0;
1735	struct read_stats *buf;
1736	bool flash_op_err = false, erased;
1737	int i;
1738	u8 *data_buf_start = data_buf, *oob_buf_start = oob_buf;
1739
1740	buf = (struct read_stats *)nandc->reg_read_buf;
1741	nandc_read_buffer_sync(nandc, true);
1742
1743	for (i = 0; i < ecc->steps; i++, buf++) {
1744		u32 flash, buffer, erased_cw;
1745		int data_len, oob_len;
1746
1747		if (i == (ecc->steps - 1)) {
1748			data_len = ecc->size - ((ecc->steps - 1) << 2);
1749			oob_len = ecc->steps << 2;
1750		} else {
1751			data_len = host->cw_data;
1752			oob_len = 0;
1753		}
1754
1755		flash = le32_to_cpu(buf->flash);
1756		buffer = le32_to_cpu(buf->buffer);
1757		erased_cw = le32_to_cpu(buf->erased_cw);
1758
1759		/*
1760		 * Check ECC failure for each codeword. ECC failure can
1761		 * happen in either of the following conditions
1762		 * 1. If number of bitflips are greater than ECC engine
1763		 *    capability.
1764		 * 2. If this codeword contains all 0xff for which erased
1765		 *    codeword detection check will be done.
1766		 */
1767		if ((flash & FS_OP_ERR) && (buffer & BS_UNCORRECTABLE_BIT)) {
1768			/*
1769			 * For BCH ECC, ignore erased codeword errors, if
1770			 * ERASED_CW bits are set.
1771			 */
1772			if (host->bch_enabled) {
1773				erased = (erased_cw & ERASED_CW) == ERASED_CW ?
1774					 true : false;
1775			/*
1776			 * For RS ECC, HW reports the erased CW by placing
1777			 * special characters at certain offsets in the buffer.
1778			 * These special characters will be valid only if
1779			 * complete page is read i.e. data_buf is not NULL.
1780			 */
1781			} else if (data_buf) {
1782				erased = erased_chunk_check_and_fixup(data_buf,
1783								      data_len);
1784			} else {
1785				erased = false;
1786			}
1787
1788			if (!erased)
1789				uncorrectable_cws |= BIT(i);
1790		/*
1791		 * Check if MPU or any other operational error (timeout,
1792		 * device failure, etc.) happened for this codeword and
1793		 * make flash_op_err true. If flash_op_err is set, then
1794		 * EIO will be returned for page read.
1795		 */
1796		} else if (flash & (FS_OP_ERR | FS_MPU_ERR)) {
1797			flash_op_err = true;
1798		/*
1799		 * No ECC or operational errors happened. Check the number of
1800		 * bits corrected and update the ecc_stats.corrected.
1801		 */
1802		} else {
1803			unsigned int stat;
1804
1805			stat = buffer & BS_CORRECTABLE_ERR_MSK;
1806			mtd->ecc_stats.corrected += stat;
1807			max_bitflips = max(max_bitflips, stat);
1808		}
1809
1810		if (data_buf)
1811			data_buf += data_len;
1812		if (oob_buf)
1813			oob_buf += oob_len + ecc->bytes;
1814	}
1815
1816	if (flash_op_err)
1817		return -EIO;
1818
1819	if (!uncorrectable_cws)
1820		return max_bitflips;
1821
1822	return check_for_erased_page(host, data_buf_start, oob_buf_start,
1823				     uncorrectable_cws, page,
1824				     max_bitflips);
1825}
1826
1827/*
1828 * helper to perform the actual page read operation, used by ecc->read_page(),
1829 * ecc->read_oob()
1830 */
1831static int read_page_ecc(struct qcom_nand_host *host, u8 *data_buf,
1832			 u8 *oob_buf, int page)
1833{
1834	struct nand_chip *chip = &host->chip;
1835	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
1836	struct nand_ecc_ctrl *ecc = &chip->ecc;
1837	u8 *data_buf_start = data_buf, *oob_buf_start = oob_buf;
1838	int i, ret;
1839
1840	config_nand_page_read(nandc);
1841
1842	/* queue cmd descs for each codeword */
1843	for (i = 0; i < ecc->steps; i++) {
1844		int data_size, oob_size;
1845
1846		if (i == (ecc->steps - 1)) {
1847			data_size = ecc->size - ((ecc->steps - 1) << 2);
1848			oob_size = (ecc->steps << 2) + host->ecc_bytes_hw +
1849				   host->spare_bytes;
1850		} else {
1851			data_size = host->cw_data;
1852			oob_size = host->ecc_bytes_hw + host->spare_bytes;
1853		}
1854
1855		if (nandc->props->is_bam) {
1856			if (data_buf && oob_buf) {
1857				nandc_set_read_loc(nandc, 0, 0, data_size, 0);
1858				nandc_set_read_loc(nandc, 1, data_size,
1859						   oob_size, 1);
1860			} else if (data_buf) {
1861				nandc_set_read_loc(nandc, 0, 0, data_size, 1);
1862			} else {
1863				nandc_set_read_loc(nandc, 0, data_size,
1864						   oob_size, 1);
1865			}
1866		}
1867
1868		config_nand_cw_read(nandc, true);
1869
1870		if (data_buf)
1871			read_data_dma(nandc, FLASH_BUF_ACC, data_buf,
1872				      data_size, 0);
1873
1874		/*
1875		 * when ecc is enabled, the controller doesn't read the real
1876		 * or dummy bad block markers in each chunk. To maintain a
1877		 * consistent layout across RAW and ECC reads, we just
1878		 * leave the real/dummy BBM offsets empty (i.e, filled with
1879		 * 0xffs)
1880		 */
1881		if (oob_buf) {
1882			int j;
1883
1884			for (j = 0; j < host->bbm_size; j++)
1885				*oob_buf++ = 0xff;
1886
1887			read_data_dma(nandc, FLASH_BUF_ACC + data_size,
1888				      oob_buf, oob_size, 0);
1889		}
1890
1891		if (data_buf)
1892			data_buf += data_size;
1893		if (oob_buf)
1894			oob_buf += oob_size;
1895	}
1896
1897	ret = submit_descs(nandc);
1898	free_descs(nandc);
1899
1900	if (ret) {
1901		dev_err(nandc->dev, "failure to read page/oob\n");
1902		return ret;
1903	}
1904
1905	return parse_read_errors(host, data_buf_start, oob_buf_start, page);
1906}
1907
1908/*
1909 * a helper that copies the last step/codeword of a page (containing free oob)
1910 * into our local buffer
1911 */
1912static int copy_last_cw(struct qcom_nand_host *host, int page)
1913{
1914	struct nand_chip *chip = &host->chip;
1915	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
1916	struct nand_ecc_ctrl *ecc = &chip->ecc;
1917	int size;
1918	int ret;
1919
1920	clear_read_regs(nandc);
1921
1922	size = host->use_ecc ? host->cw_data : host->cw_size;
1923
1924	/* prepare a clean read buffer */
1925	memset(nandc->data_buffer, 0xff, size);
1926
1927	set_address(host, host->cw_size * (ecc->steps - 1), page);
1928	update_rw_regs(host, 1, true);
1929
1930	config_nand_single_cw_page_read(nandc, host->use_ecc);
1931
1932	read_data_dma(nandc, FLASH_BUF_ACC, nandc->data_buffer, size, 0);
1933
1934	ret = submit_descs(nandc);
1935	if (ret)
1936		dev_err(nandc->dev, "failed to copy last codeword\n");
1937
1938	free_descs(nandc);
1939
1940	return ret;
1941}
1942
1943/* implements ecc->read_page() */
1944static int qcom_nandc_read_page(struct nand_chip *chip, uint8_t *buf,
1945				int oob_required, int page)
1946{
1947	struct qcom_nand_host *host = to_qcom_nand_host(chip);
1948	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
1949	u8 *data_buf, *oob_buf = NULL;
1950
1951	nand_read_page_op(chip, page, 0, NULL, 0);
1952	data_buf = buf;
1953	oob_buf = oob_required ? chip->oob_poi : NULL;
1954
1955	clear_bam_transaction(nandc);
1956
1957	return read_page_ecc(host, data_buf, oob_buf, page);
1958}
1959
1960/* implements ecc->read_page_raw() */
1961static int qcom_nandc_read_page_raw(struct nand_chip *chip, uint8_t *buf,
1962				    int oob_required, int page)
1963{
1964	struct mtd_info *mtd = nand_to_mtd(chip);
1965	struct qcom_nand_host *host = to_qcom_nand_host(chip);
1966	struct nand_ecc_ctrl *ecc = &chip->ecc;
1967	int cw, ret;
1968	u8 *data_buf = buf, *oob_buf = chip->oob_poi;
1969
1970	for (cw = 0; cw < ecc->steps; cw++) {
1971		ret = qcom_nandc_read_cw_raw(mtd, chip, data_buf, oob_buf,
1972					     page, cw);
1973		if (ret)
1974			return ret;
1975
1976		data_buf += host->cw_data;
1977		oob_buf += ecc->bytes;
1978	}
1979
1980	return 0;
1981}
1982
1983/* implements ecc->read_oob() */
1984static int qcom_nandc_read_oob(struct nand_chip *chip, int page)
1985{
1986	struct qcom_nand_host *host = to_qcom_nand_host(chip);
1987	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
1988	struct nand_ecc_ctrl *ecc = &chip->ecc;
1989
1990	clear_read_regs(nandc);
1991	clear_bam_transaction(nandc);
1992
1993	host->use_ecc = true;
1994	set_address(host, 0, page);
1995	update_rw_regs(host, ecc->steps, true);
1996
1997	return read_page_ecc(host, NULL, chip->oob_poi, page);
1998}
1999
2000/* implements ecc->write_page() */
2001static int qcom_nandc_write_page(struct nand_chip *chip, const uint8_t *buf,
2002				 int oob_required, int page)
2003{
2004	struct qcom_nand_host *host = to_qcom_nand_host(chip);
2005	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
2006	struct nand_ecc_ctrl *ecc = &chip->ecc;
2007	u8 *data_buf, *oob_buf;
2008	int i, ret;
2009
2010	nand_prog_page_begin_op(chip, page, 0, NULL, 0);
2011
2012	clear_read_regs(nandc);
2013	clear_bam_transaction(nandc);
2014
2015	data_buf = (u8 *)buf;
2016	oob_buf = chip->oob_poi;
2017
2018	host->use_ecc = true;
2019	update_rw_regs(host, ecc->steps, false);
2020	config_nand_page_write(nandc);
2021
2022	for (i = 0; i < ecc->steps; i++) {
2023		int data_size, oob_size;
2024
2025		if (i == (ecc->steps - 1)) {
2026			data_size = ecc->size - ((ecc->steps - 1) << 2);
2027			oob_size = (ecc->steps << 2) + host->ecc_bytes_hw +
2028				   host->spare_bytes;
2029		} else {
2030			data_size = host->cw_data;
2031			oob_size = ecc->bytes;
2032		}
2033
2034
2035		write_data_dma(nandc, FLASH_BUF_ACC, data_buf, data_size,
2036			       i == (ecc->steps - 1) ? NAND_BAM_NO_EOT : 0);
2037
2038		/*
2039		 * when ECC is enabled, we don't really need to write anything
2040		 * to oob for the first n - 1 codewords since these oob regions
2041		 * just contain ECC bytes that's written by the controller
2042		 * itself. For the last codeword, we skip the bbm positions and
2043		 * write to the free oob area.
2044		 */
2045		if (i == (ecc->steps - 1)) {
2046			oob_buf += host->bbm_size;
2047
2048			write_data_dma(nandc, FLASH_BUF_ACC + data_size,
2049				       oob_buf, oob_size, 0);
2050		}
2051
2052		config_nand_cw_write(nandc);
2053
2054		data_buf += data_size;
2055		oob_buf += oob_size;
2056	}
2057
2058	ret = submit_descs(nandc);
2059	if (ret)
2060		dev_err(nandc->dev, "failure to write page\n");
2061
2062	free_descs(nandc);
2063
2064	if (!ret)
2065		ret = nand_prog_page_end_op(chip);
2066
2067	return ret;
2068}
2069
2070/* implements ecc->write_page_raw() */
2071static int qcom_nandc_write_page_raw(struct nand_chip *chip,
2072				     const uint8_t *buf, int oob_required,
2073				     int page)
2074{
2075	struct mtd_info *mtd = nand_to_mtd(chip);
2076	struct qcom_nand_host *host = to_qcom_nand_host(chip);
2077	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
2078	struct nand_ecc_ctrl *ecc = &chip->ecc;
2079	u8 *data_buf, *oob_buf;
2080	int i, ret;
2081
2082	nand_prog_page_begin_op(chip, page, 0, NULL, 0);
2083	clear_read_regs(nandc);
2084	clear_bam_transaction(nandc);
2085
2086	data_buf = (u8 *)buf;
2087	oob_buf = chip->oob_poi;
2088
2089	host->use_ecc = false;
2090	update_rw_regs(host, ecc->steps, false);
2091	config_nand_page_write(nandc);
2092
2093	for (i = 0; i < ecc->steps; i++) {
2094		int data_size1, data_size2, oob_size1, oob_size2;
2095		int reg_off = FLASH_BUF_ACC;
2096
2097		data_size1 = mtd->writesize - host->cw_size * (ecc->steps - 1);
2098		oob_size1 = host->bbm_size;
2099
2100		if (i == (ecc->steps - 1)) {
2101			data_size2 = ecc->size - data_size1 -
2102				     ((ecc->steps - 1) << 2);
2103			oob_size2 = (ecc->steps << 2) + host->ecc_bytes_hw +
2104				    host->spare_bytes;
2105		} else {
2106			data_size2 = host->cw_data - data_size1;
2107			oob_size2 = host->ecc_bytes_hw + host->spare_bytes;
2108		}
2109
2110		write_data_dma(nandc, reg_off, data_buf, data_size1,
2111			       NAND_BAM_NO_EOT);
2112		reg_off += data_size1;
2113		data_buf += data_size1;
2114
2115		write_data_dma(nandc, reg_off, oob_buf, oob_size1,
2116			       NAND_BAM_NO_EOT);
2117		reg_off += oob_size1;
2118		oob_buf += oob_size1;
2119
2120		write_data_dma(nandc, reg_off, data_buf, data_size2,
2121			       NAND_BAM_NO_EOT);
2122		reg_off += data_size2;
2123		data_buf += data_size2;
2124
2125		write_data_dma(nandc, reg_off, oob_buf, oob_size2, 0);
2126		oob_buf += oob_size2;
2127
2128		config_nand_cw_write(nandc);
2129	}
2130
2131	ret = submit_descs(nandc);
2132	if (ret)
2133		dev_err(nandc->dev, "failure to write raw page\n");
2134
2135	free_descs(nandc);
2136
2137	if (!ret)
2138		ret = nand_prog_page_end_op(chip);
2139
2140	return ret;
2141}
2142
2143/*
2144 * implements ecc->write_oob()
2145 *
2146 * the NAND controller cannot write only data or only OOB within a codeword
2147 * since ECC is calculated for the combined codeword. So update the OOB from
2148 * chip->oob_poi, and pad the data area with OxFF before writing.
2149 */
2150static int qcom_nandc_write_oob(struct nand_chip *chip, int page)
2151{
2152	struct mtd_info *mtd = nand_to_mtd(chip);
2153	struct qcom_nand_host *host = to_qcom_nand_host(chip);
2154	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
2155	struct nand_ecc_ctrl *ecc = &chip->ecc;
2156	u8 *oob = chip->oob_poi;
2157	int data_size, oob_size;
2158	int ret;
2159
2160	host->use_ecc = true;
2161	clear_bam_transaction(nandc);
2162
2163	/* calculate the data and oob size for the last codeword/step */
2164	data_size = ecc->size - ((ecc->steps - 1) << 2);
2165	oob_size = mtd->oobavail;
2166
2167	memset(nandc->data_buffer, 0xff, host->cw_data);
2168	/* override new oob content to last codeword */
2169	mtd_ooblayout_get_databytes(mtd, nandc->data_buffer + data_size, oob,
2170				    0, mtd->oobavail);
2171
2172	set_address(host, host->cw_size * (ecc->steps - 1), page);
2173	update_rw_regs(host, 1, false);
2174
2175	config_nand_page_write(nandc);
2176	write_data_dma(nandc, FLASH_BUF_ACC,
2177		       nandc->data_buffer, data_size + oob_size, 0);
2178	config_nand_cw_write(nandc);
2179
2180	ret = submit_descs(nandc);
2181
2182	free_descs(nandc);
2183
2184	if (ret) {
2185		dev_err(nandc->dev, "failure to write oob\n");
2186		return -EIO;
2187	}
2188
2189	return nand_prog_page_end_op(chip);
2190}
2191
2192static int qcom_nandc_block_bad(struct nand_chip *chip, loff_t ofs)
2193{
2194	struct mtd_info *mtd = nand_to_mtd(chip);
2195	struct qcom_nand_host *host = to_qcom_nand_host(chip);
2196	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
2197	struct nand_ecc_ctrl *ecc = &chip->ecc;
2198	int page, ret, bbpos, bad = 0;
2199
2200	page = (int)(ofs >> chip->page_shift) & chip->pagemask;
2201
2202	/*
2203	 * configure registers for a raw sub page read, the address is set to
2204	 * the beginning of the last codeword, we don't care about reading ecc
2205	 * portion of oob. we just want the first few bytes from this codeword
2206	 * that contains the BBM
2207	 */
2208	host->use_ecc = false;
2209
2210	clear_bam_transaction(nandc);
2211	ret = copy_last_cw(host, page);
2212	if (ret)
2213		goto err;
2214
2215	if (check_flash_errors(host, 1)) {
2216		dev_warn(nandc->dev, "error when trying to read BBM\n");
2217		goto err;
2218	}
2219
2220	bbpos = mtd->writesize - host->cw_size * (ecc->steps - 1);
2221
2222	bad = nandc->data_buffer[bbpos] != 0xff;
2223
2224	if (chip->options & NAND_BUSWIDTH_16)
2225		bad = bad || (nandc->data_buffer[bbpos + 1] != 0xff);
2226err:
2227	return bad;
2228}
2229
2230static int qcom_nandc_block_markbad(struct nand_chip *chip, loff_t ofs)
2231{
2232	struct qcom_nand_host *host = to_qcom_nand_host(chip);
2233	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
2234	struct nand_ecc_ctrl *ecc = &chip->ecc;
2235	int page, ret;
2236
2237	clear_read_regs(nandc);
2238	clear_bam_transaction(nandc);
2239
2240	/*
2241	 * to mark the BBM as bad, we flash the entire last codeword with 0s.
2242	 * we don't care about the rest of the content in the codeword since
2243	 * we aren't going to use this block again
2244	 */
2245	memset(nandc->data_buffer, 0x00, host->cw_size);
2246
2247	page = (int)(ofs >> chip->page_shift) & chip->pagemask;
2248
2249	/* prepare write */
2250	host->use_ecc = false;
2251	set_address(host, host->cw_size * (ecc->steps - 1), page);
2252	update_rw_regs(host, 1, false);
2253
2254	config_nand_page_write(nandc);
2255	write_data_dma(nandc, FLASH_BUF_ACC,
2256		       nandc->data_buffer, host->cw_size, 0);
2257	config_nand_cw_write(nandc);
2258
2259	ret = submit_descs(nandc);
2260
2261	free_descs(nandc);
2262
2263	if (ret) {
2264		dev_err(nandc->dev, "failure to update BBM\n");
2265		return -EIO;
2266	}
2267
2268	return nand_prog_page_end_op(chip);
2269}
2270
2271/*
2272 * the three functions below implement chip->legacy.read_byte(),
2273 * chip->legacy.read_buf() and chip->legacy.write_buf() respectively. these
2274 * aren't used for reading/writing page data, they are used for smaller data
2275 * like reading	id, status etc
2276 */
2277static uint8_t qcom_nandc_read_byte(struct nand_chip *chip)
2278{
2279	struct qcom_nand_host *host = to_qcom_nand_host(chip);
2280	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
2281	u8 *buf = nandc->data_buffer;
2282	u8 ret = 0x0;
2283
2284	if (host->last_command == NAND_CMD_STATUS) {
2285		ret = host->status;
2286
2287		host->status = NAND_STATUS_READY | NAND_STATUS_WP;
2288
2289		return ret;
2290	}
2291
2292	if (nandc->buf_start < nandc->buf_count)
2293		ret = buf[nandc->buf_start++];
2294
2295	return ret;
2296}
2297
2298static void qcom_nandc_read_buf(struct nand_chip *chip, uint8_t *buf, int len)
2299{
2300	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
2301	int real_len = min_t(size_t, len, nandc->buf_count - nandc->buf_start);
2302
2303	memcpy(buf, nandc->data_buffer + nandc->buf_start, real_len);
2304	nandc->buf_start += real_len;
2305}
2306
2307static void qcom_nandc_write_buf(struct nand_chip *chip, const uint8_t *buf,
2308				 int len)
2309{
2310	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
2311	int real_len = min_t(size_t, len, nandc->buf_count - nandc->buf_start);
2312
2313	memcpy(nandc->data_buffer + nandc->buf_start, buf, real_len);
2314
2315	nandc->buf_start += real_len;
2316}
2317
2318/* we support only one external chip for now */
2319static void qcom_nandc_select_chip(struct nand_chip *chip, int chipnr)
2320{
2321	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
2322
2323	if (chipnr <= 0)
2324		return;
2325
2326	dev_warn(nandc->dev, "invalid chip select\n");
2327}
2328
2329/*
2330 * NAND controller page layout info
2331 *
2332 * Layout with ECC enabled:
2333 *
2334 * |----------------------|  |---------------------------------|
2335 * |           xx.......yy|  |             *********xx.......yy|
2336 * |    DATA   xx..ECC..yy|  |    DATA     **SPARE**xx..ECC..yy|
2337 * |   (516)   xx.......yy|  |  (516-n*4)  **(n*4)**xx.......yy|
2338 * |           xx.......yy|  |             *********xx.......yy|
2339 * |----------------------|  |---------------------------------|
2340 *     codeword 1,2..n-1                  codeword n
2341 *  <---(528/532 Bytes)-->    <-------(528/532 Bytes)--------->
2342 *
2343 * n = Number of codewords in the page
2344 * . = ECC bytes
2345 * * = Spare/free bytes
2346 * x = Unused byte(s)
2347 * y = Reserved byte(s)
2348 *
2349 * 2K page: n = 4, spare = 16 bytes
2350 * 4K page: n = 8, spare = 32 bytes
2351 * 8K page: n = 16, spare = 64 bytes
2352 *
2353 * the qcom nand controller operates at a sub page/codeword level. each
2354 * codeword is 528 and 532 bytes for 4 bit and 8 bit ECC modes respectively.
2355 * the number of ECC bytes vary based on the ECC strength and the bus width.
2356 *
2357 * the first n - 1 codewords contains 516 bytes of user data, the remaining
2358 * 12/16 bytes consist of ECC and reserved data. The nth codeword contains
2359 * both user data and spare(oobavail) bytes that sum up to 516 bytes.
2360 *
2361 * When we access a page with ECC enabled, the reserved bytes(s) are not
2362 * accessible at all. When reading, we fill up these unreadable positions
2363 * with 0xffs. When writing, the controller skips writing the inaccessible
2364 * bytes.
2365 *
2366 * Layout with ECC disabled:
2367 *
2368 * |------------------------------|  |---------------------------------------|
2369 * |         yy          xx.......|  |         bb          *********xx.......|
2370 * |  DATA1  yy  DATA2   xx..ECC..|  |  DATA1  bb  DATA2   **SPARE**xx..ECC..|
2371 * | (size1) yy (size2)  xx.......|  | (size1) bb (size2)  **(n*4)**xx.......|
2372 * |         yy          xx.......|  |         bb          *********xx.......|
2373 * |------------------------------|  |---------------------------------------|
2374 *         codeword 1,2..n-1                        codeword n
2375 *  <-------(528/532 Bytes)------>    <-----------(528/532 Bytes)----------->
2376 *
2377 * n = Number of codewords in the page
2378 * . = ECC bytes
2379 * * = Spare/free bytes
2380 * x = Unused byte(s)
2381 * y = Dummy Bad Bock byte(s)
2382 * b = Real Bad Block byte(s)
2383 * size1/size2 = function of codeword size and 'n'
2384 *
2385 * when the ECC block is disabled, one reserved byte (or two for 16 bit bus
2386 * width) is now accessible. For the first n - 1 codewords, these are dummy Bad
2387 * Block Markers. In the last codeword, this position contains the real BBM
2388 *
2389 * In order to have a consistent layout between RAW and ECC modes, we assume
2390 * the following OOB layout arrangement:
2391 *
2392 * |-----------|  |--------------------|
2393 * |yyxx.......|  |bb*********xx.......|
2394 * |yyxx..ECC..|  |bb*FREEOOB*xx..ECC..|
2395 * |yyxx.......|  |bb*********xx.......|
2396 * |yyxx.......|  |bb*********xx.......|
2397 * |-----------|  |--------------------|
2398 *  first n - 1       nth OOB region
2399 *  OOB regions
2400 *
2401 * n = Number of codewords in the page
2402 * . = ECC bytes
2403 * * = FREE OOB bytes
2404 * y = Dummy bad block byte(s) (inaccessible when ECC enabled)
2405 * x = Unused byte(s)
2406 * b = Real bad block byte(s) (inaccessible when ECC enabled)
2407 *
2408 * This layout is read as is when ECC is disabled. When ECC is enabled, the
2409 * inaccessible Bad Block byte(s) are ignored when we write to a page/oob,
2410 * and assumed as 0xffs when we read a page/oob. The ECC, unused and
2411 * dummy/real bad block bytes are grouped as ecc bytes (i.e, ecc->bytes is
2412 * the sum of the three).
2413 */
2414static int qcom_nand_ooblayout_ecc(struct mtd_info *mtd, int section,
2415				   struct mtd_oob_region *oobregion)
2416{
2417	struct nand_chip *chip = mtd_to_nand(mtd);
2418	struct qcom_nand_host *host = to_qcom_nand_host(chip);
2419	struct nand_ecc_ctrl *ecc = &chip->ecc;
2420
2421	if (section > 1)
2422		return -ERANGE;
2423
2424	if (!section) {
2425		oobregion->length = (ecc->bytes * (ecc->steps - 1)) +
2426				    host->bbm_size;
2427		oobregion->offset = 0;
2428	} else {
2429		oobregion->length = host->ecc_bytes_hw + host->spare_bytes;
2430		oobregion->offset = mtd->oobsize - oobregion->length;
2431	}
2432
2433	return 0;
2434}
2435
2436static int qcom_nand_ooblayout_free(struct mtd_info *mtd, int section,
2437				     struct mtd_oob_region *oobregion)
2438{
2439	struct nand_chip *chip = mtd_to_nand(mtd);
2440	struct qcom_nand_host *host = to_qcom_nand_host(chip);
2441	struct nand_ecc_ctrl *ecc = &chip->ecc;
2442
2443	if (section)
2444		return -ERANGE;
2445
2446	oobregion->length = ecc->steps * 4;
2447	oobregion->offset = ((ecc->steps - 1) * ecc->bytes) + host->bbm_size;
2448
2449	return 0;
2450}
2451
2452static const struct mtd_ooblayout_ops qcom_nand_ooblayout_ops = {
2453	.ecc = qcom_nand_ooblayout_ecc,
2454	.free = qcom_nand_ooblayout_free,
2455};
2456
2457static int
2458qcom_nandc_calc_ecc_bytes(int step_size, int strength)
2459{
2460	return strength == 4 ? 12 : 16;
2461}
2462NAND_ECC_CAPS_SINGLE(qcom_nandc_ecc_caps, qcom_nandc_calc_ecc_bytes,
2463		     NANDC_STEP_SIZE, 4, 8);
2464
2465static int qcom_nand_attach_chip(struct nand_chip *chip)
2466{
2467	struct mtd_info *mtd = nand_to_mtd(chip);
2468	struct qcom_nand_host *host = to_qcom_nand_host(chip);
2469	struct nand_ecc_ctrl *ecc = &chip->ecc;
2470	struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
2471	int cwperpage, bad_block_byte, ret;
2472	bool wide_bus;
2473	int ecc_mode = 1;
2474
2475	/* controller only supports 512 bytes data steps */
2476	ecc->size = NANDC_STEP_SIZE;
2477	wide_bus = chip->options & NAND_BUSWIDTH_16 ? true : false;
2478	cwperpage = mtd->writesize / NANDC_STEP_SIZE;
2479
2480	/*
2481	 * Each CW has 4 available OOB bytes which will be protected with ECC
2482	 * so remaining bytes can be used for ECC.
2483	 */
2484	ret = nand_ecc_choose_conf(chip, &qcom_nandc_ecc_caps,
2485				   mtd->oobsize - (cwperpage * 4));
2486	if (ret) {
2487		dev_err(nandc->dev, "No valid ECC settings possible\n");
2488		return ret;
2489	}
2490
2491	if (ecc->strength >= 8) {
2492		/* 8 bit ECC defaults to BCH ECC on all platforms */
2493		host->bch_enabled = true;
2494		ecc_mode = 1;
2495
2496		if (wide_bus) {
2497			host->ecc_bytes_hw = 14;
2498			host->spare_bytes = 0;
2499			host->bbm_size = 2;
2500		} else {
2501			host->ecc_bytes_hw = 13;
2502			host->spare_bytes = 2;
2503			host->bbm_size = 1;
2504		}
2505	} else {
2506		/*
2507		 * if the controller supports BCH for 4 bit ECC, the controller
2508		 * uses lesser bytes for ECC. If RS is used, the ECC bytes is
2509		 * always 10 bytes
2510		 */
2511		if (nandc->props->ecc_modes & ECC_BCH_4BIT) {
2512			/* BCH */
2513			host->bch_enabled = true;
2514			ecc_mode = 0;
2515
2516			if (wide_bus) {
2517				host->ecc_bytes_hw = 8;
2518				host->spare_bytes = 2;
2519				host->bbm_size = 2;
2520			} else {
2521				host->ecc_bytes_hw = 7;
2522				host->spare_bytes = 4;
2523				host->bbm_size = 1;
2524			}
2525		} else {
2526			/* RS */
2527			host->ecc_bytes_hw = 10;
2528
2529			if (wide_bus) {
2530				host->spare_bytes = 0;
2531				host->bbm_size = 2;
2532			} else {
2533				host->spare_bytes = 1;
2534				host->bbm_size = 1;
2535			}
2536		}
2537	}
2538
2539	/*
2540	 * we consider ecc->bytes as the sum of all the non-data content in a
2541	 * step. It gives us a clean representation of the oob area (even if
2542	 * all the bytes aren't used for ECC).It is always 16 bytes for 8 bit
2543	 * ECC and 12 bytes for 4 bit ECC
2544	 */
2545	ecc->bytes = host->ecc_bytes_hw + host->spare_bytes + host->bbm_size;
2546
2547	ecc->read_page		= qcom_nandc_read_page;
2548	ecc->read_page_raw	= qcom_nandc_read_page_raw;
2549	ecc->read_oob		= qcom_nandc_read_oob;
2550	ecc->write_page		= qcom_nandc_write_page;
2551	ecc->write_page_raw	= qcom_nandc_write_page_raw;
2552	ecc->write_oob		= qcom_nandc_write_oob;
2553
2554	ecc->engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST;
2555
2556	mtd_set_ooblayout(mtd, &qcom_nand_ooblayout_ops);
2557
2558	nandc->max_cwperpage = max_t(unsigned int, nandc->max_cwperpage,
2559				     cwperpage);
2560
2561	/*
2562	 * DATA_UD_BYTES varies based on whether the read/write command protects
2563	 * spare data with ECC too. We protect spare data by default, so we set
2564	 * it to main + spare data, which are 512 and 4 bytes respectively.
2565	 */
2566	host->cw_data = 516;
2567
2568	/*
2569	 * total bytes in a step, either 528 bytes for 4 bit ECC, or 532 bytes
2570	 * for 8 bit ECC
2571	 */
2572	host->cw_size = host->cw_data + ecc->bytes;
2573	bad_block_byte = mtd->writesize - host->cw_size * (cwperpage - 1) + 1;
2574
2575	host->cfg0 = (cwperpage - 1) << CW_PER_PAGE
2576				| host->cw_data << UD_SIZE_BYTES
2577				| 0 << DISABLE_STATUS_AFTER_WRITE
2578				| 5 << NUM_ADDR_CYCLES
2579				| host->ecc_bytes_hw << ECC_PARITY_SIZE_BYTES_RS
2580				| 0 << STATUS_BFR_READ
2581				| 1 << SET_RD_MODE_AFTER_STATUS
2582				| host->spare_bytes << SPARE_SIZE_BYTES;
2583
2584	host->cfg1 = 7 << NAND_RECOVERY_CYCLES
2585				| 0 <<  CS_ACTIVE_BSY
2586				| bad_block_byte << BAD_BLOCK_BYTE_NUM
2587				| 0 << BAD_BLOCK_IN_SPARE_AREA
2588				| 2 << WR_RD_BSY_GAP
2589				| wide_bus << WIDE_FLASH
2590				| host->bch_enabled << ENABLE_BCH_ECC;
2591
2592	host->cfg0_raw = (cwperpage - 1) << CW_PER_PAGE
2593				| host->cw_size << UD_SIZE_BYTES
2594				| 5 << NUM_ADDR_CYCLES
2595				| 0 << SPARE_SIZE_BYTES;
2596
2597	host->cfg1_raw = 7 << NAND_RECOVERY_CYCLES
2598				| 0 << CS_ACTIVE_BSY
2599				| 17 << BAD_BLOCK_BYTE_NUM
2600				| 1 << BAD_BLOCK_IN_SPARE_AREA
2601				| 2 << WR_RD_BSY_GAP
2602				| wide_bus << WIDE_FLASH
2603				| 1 << DEV0_CFG1_ECC_DISABLE;
2604
2605	host->ecc_bch_cfg = !host->bch_enabled << ECC_CFG_ECC_DISABLE
2606				| 0 << ECC_SW_RESET
2607				| host->cw_data << ECC_NUM_DATA_BYTES
2608				| 1 << ECC_FORCE_CLK_OPEN
2609				| ecc_mode << ECC_MODE
2610				| host->ecc_bytes_hw << ECC_PARITY_SIZE_BYTES_BCH;
2611
2612	host->ecc_buf_cfg = 0x203 << NUM_STEPS;
2613
2614	host->clrflashstatus = FS_READY_BSY_N;
2615	host->clrreadstatus = 0xc0;
2616	nandc->regs->erased_cw_detect_cfg_clr =
2617		cpu_to_le32(CLR_ERASED_PAGE_DET);
2618	nandc->regs->erased_cw_detect_cfg_set =
2619		cpu_to_le32(SET_ERASED_PAGE_DET);
2620
2621	dev_dbg(nandc->dev,
2622		"cfg0 %x cfg1 %x ecc_buf_cfg %x ecc_bch cfg %x cw_size %d cw_data %d strength %d parity_bytes %d steps %d\n",
2623		host->cfg0, host->cfg1, host->ecc_buf_cfg, host->ecc_bch_cfg,
2624		host->cw_size, host->cw_data, ecc->strength, ecc->bytes,
2625		cwperpage);
2626
2627	return 0;
2628}
2629
2630static const struct nand_controller_ops qcom_nandc_ops = {
2631	.attach_chip = qcom_nand_attach_chip,
2632};
2633
2634static void qcom_nandc_unalloc(struct qcom_nand_controller *nandc)
2635{
2636	if (nandc->props->is_bam) {
2637		if (!dma_mapping_error(nandc->dev, nandc->reg_read_dma))
2638			dma_unmap_single(nandc->dev, nandc->reg_read_dma,
2639					 MAX_REG_RD *
2640					 sizeof(*nandc->reg_read_buf),
2641					 DMA_FROM_DEVICE);
2642
2643		if (nandc->tx_chan)
2644			dma_release_channel(nandc->tx_chan);
2645
2646		if (nandc->rx_chan)
2647			dma_release_channel(nandc->rx_chan);
2648
2649		if (nandc->cmd_chan)
2650			dma_release_channel(nandc->cmd_chan);
2651	} else {
2652		if (nandc->chan)
2653			dma_release_channel(nandc->chan);
2654	}
2655}
2656
2657static int qcom_nandc_alloc(struct qcom_nand_controller *nandc)
2658{
2659	int ret;
2660
2661	ret = dma_set_coherent_mask(nandc->dev, DMA_BIT_MASK(32));
2662	if (ret) {
2663		dev_err(nandc->dev, "failed to set DMA mask\n");
2664		return ret;
2665	}
2666
2667	/*
2668	 * we use the internal buffer for reading ONFI params, reading small
2669	 * data like ID and status, and preforming read-copy-write operations
2670	 * when writing to a codeword partially. 532 is the maximum possible
2671	 * size of a codeword for our nand controller
2672	 */
2673	nandc->buf_size = 532;
2674
2675	nandc->data_buffer = devm_kzalloc(nandc->dev, nandc->buf_size,
2676					GFP_KERNEL);
2677	if (!nandc->data_buffer)
2678		return -ENOMEM;
2679
2680	nandc->regs = devm_kzalloc(nandc->dev, sizeof(*nandc->regs),
2681					GFP_KERNEL);
2682	if (!nandc->regs)
2683		return -ENOMEM;
2684
2685	nandc->reg_read_buf = devm_kcalloc(nandc->dev,
2686				MAX_REG_RD, sizeof(*nandc->reg_read_buf),
2687				GFP_KERNEL);
2688	if (!nandc->reg_read_buf)
2689		return -ENOMEM;
2690
2691	if (nandc->props->is_bam) {
2692		nandc->reg_read_dma =
2693			dma_map_single(nandc->dev, nandc->reg_read_buf,
2694				       MAX_REG_RD *
2695				       sizeof(*nandc->reg_read_buf),
2696				       DMA_FROM_DEVICE);
2697		if (dma_mapping_error(nandc->dev, nandc->reg_read_dma)) {
2698			dev_err(nandc->dev, "failed to DMA MAP reg buffer\n");
2699			return -EIO;
2700		}
2701
2702		nandc->tx_chan = dma_request_chan(nandc->dev, "tx");
2703		if (IS_ERR(nandc->tx_chan)) {
2704			ret = PTR_ERR(nandc->tx_chan);
2705			nandc->tx_chan = NULL;
2706			dev_err_probe(nandc->dev, ret,
2707				      "tx DMA channel request failed\n");
2708			goto unalloc;
2709		}
2710
2711		nandc->rx_chan = dma_request_chan(nandc->dev, "rx");
2712		if (IS_ERR(nandc->rx_chan)) {
2713			ret = PTR_ERR(nandc->rx_chan);
2714			nandc->rx_chan = NULL;
2715			dev_err_probe(nandc->dev, ret,
2716				      "rx DMA channel request failed\n");
2717			goto unalloc;
2718		}
2719
2720		nandc->cmd_chan = dma_request_chan(nandc->dev, "cmd");
2721		if (IS_ERR(nandc->cmd_chan)) {
2722			ret = PTR_ERR(nandc->cmd_chan);
2723			nandc->cmd_chan = NULL;
2724			dev_err_probe(nandc->dev, ret,
2725				      "cmd DMA channel request failed\n");
2726			goto unalloc;
2727		}
2728
2729		/*
2730		 * Initially allocate BAM transaction to read ONFI param page.
2731		 * After detecting all the devices, this BAM transaction will
2732		 * be freed and the next BAM tranasction will be allocated with
2733		 * maximum codeword size
2734		 */
2735		nandc->max_cwperpage = 1;
2736		nandc->bam_txn = alloc_bam_transaction(nandc);
2737		if (!nandc->bam_txn) {
2738			dev_err(nandc->dev,
2739				"failed to allocate bam transaction\n");
2740			ret = -ENOMEM;
2741			goto unalloc;
2742		}
2743	} else {
2744		nandc->chan = dma_request_chan(nandc->dev, "rxtx");
2745		if (IS_ERR(nandc->chan)) {
2746			ret = PTR_ERR(nandc->chan);
2747			nandc->chan = NULL;
2748			dev_err_probe(nandc->dev, ret,
2749				      "rxtx DMA channel request failed\n");
2750			return ret;
2751		}
2752	}
2753
2754	INIT_LIST_HEAD(&nandc->desc_list);
2755	INIT_LIST_HEAD(&nandc->host_list);
2756
2757	nand_controller_init(&nandc->controller);
2758	nandc->controller.ops = &qcom_nandc_ops;
2759
2760	return 0;
2761unalloc:
2762	qcom_nandc_unalloc(nandc);
2763	return ret;
2764}
2765
2766/* one time setup of a few nand controller registers */
2767static int qcom_nandc_setup(struct qcom_nand_controller *nandc)
2768{
2769	u32 nand_ctrl;
2770
2771	/* kill onenand */
2772	if (!nandc->props->is_qpic)
2773		nandc_write(nandc, SFLASHC_BURST_CFG, 0);
2774	nandc_write(nandc, dev_cmd_reg_addr(nandc, NAND_DEV_CMD_VLD),
2775		    NAND_DEV_CMD_VLD_VAL);
2776
2777	/* enable ADM or BAM DMA */
2778	if (nandc->props->is_bam) {
2779		nand_ctrl = nandc_read(nandc, NAND_CTRL);
2780
2781		/*
2782		 *NAND_CTRL is an operational registers, and CPU
2783		 * access to operational registers are read only
2784		 * in BAM mode. So update the NAND_CTRL register
2785		 * only if it is not in BAM mode. In most cases BAM
2786		 * mode will be enabled in bootloader
2787		 */
2788		if (!(nand_ctrl & BAM_MODE_EN))
2789			nandc_write(nandc, NAND_CTRL, nand_ctrl | BAM_MODE_EN);
2790	} else {
2791		nandc_write(nandc, NAND_FLASH_CHIP_SELECT, DM_EN);
2792	}
2793
2794	/* save the original values of these registers */
2795	nandc->cmd1 = nandc_read(nandc, dev_cmd_reg_addr(nandc, NAND_DEV_CMD1));
2796	nandc->vld = NAND_DEV_CMD_VLD_VAL;
2797
2798	return 0;
2799}
2800
2801static int qcom_nand_host_init_and_register(struct qcom_nand_controller *nandc,
2802					    struct qcom_nand_host *host,
2803					    struct device_node *dn)
2804{
2805	struct nand_chip *chip = &host->chip;
2806	struct mtd_info *mtd = nand_to_mtd(chip);
2807	struct device *dev = nandc->dev;
2808	int ret;
2809
2810	ret = of_property_read_u32(dn, "reg", &host->cs);
2811	if (ret) {
2812		dev_err(dev, "can't get chip-select\n");
2813		return -ENXIO;
2814	}
2815
2816	nand_set_flash_node(chip, dn);
2817	mtd->name = devm_kasprintf(dev, GFP_KERNEL, "qcom_nand.%d", host->cs);
2818	if (!mtd->name)
2819		return -ENOMEM;
2820
2821	mtd->owner = THIS_MODULE;
2822	mtd->dev.parent = dev;
2823
2824	chip->legacy.cmdfunc	= qcom_nandc_command;
2825	chip->legacy.select_chip	= qcom_nandc_select_chip;
2826	chip->legacy.read_byte	= qcom_nandc_read_byte;
2827	chip->legacy.read_buf	= qcom_nandc_read_buf;
2828	chip->legacy.write_buf	= qcom_nandc_write_buf;
2829	chip->legacy.set_features	= nand_get_set_features_notsupp;
2830	chip->legacy.get_features	= nand_get_set_features_notsupp;
2831
2832	/*
2833	 * the bad block marker is readable only when we read the last codeword
2834	 * of a page with ECC disabled. currently, the nand_base and nand_bbt
2835	 * helpers don't allow us to read BB from a nand chip with ECC
2836	 * disabled (MTD_OPS_PLACE_OOB is set by default). use the block_bad
2837	 * and block_markbad helpers until we permanently switch to using
2838	 * MTD_OPS_RAW for all drivers (with the help of badblockbits)
2839	 */
2840	chip->legacy.block_bad		= qcom_nandc_block_bad;
2841	chip->legacy.block_markbad	= qcom_nandc_block_markbad;
2842
2843	chip->controller = &nandc->controller;
2844	chip->options |= NAND_NO_SUBPAGE_WRITE | NAND_USES_DMA |
2845			 NAND_SKIP_BBTSCAN;
2846
2847	/* set up initial status value */
2848	host->status = NAND_STATUS_READY | NAND_STATUS_WP;
2849
2850	ret = nand_scan(chip, 1);
2851	if (ret)
2852		return ret;
2853
2854	if (nandc->props->is_bam) {
2855		free_bam_transaction(nandc);
2856		nandc->bam_txn = alloc_bam_transaction(nandc);
2857		if (!nandc->bam_txn) {
2858			dev_err(nandc->dev,
2859				"failed to allocate bam transaction\n");
2860			return -ENOMEM;
2861		}
2862	}
2863
2864	ret = mtd_device_register(mtd, NULL, 0);
2865	if (ret)
2866		nand_cleanup(chip);
2867
2868	return ret;
2869}
2870
2871static int qcom_probe_nand_devices(struct qcom_nand_controller *nandc)
2872{
2873	struct device *dev = nandc->dev;
2874	struct device_node *dn = dev->of_node, *child;
2875	struct qcom_nand_host *host;
2876	int ret = -ENODEV;
2877
2878	for_each_available_child_of_node(dn, child) {
2879		host = devm_kzalloc(dev, sizeof(*host), GFP_KERNEL);
2880		if (!host) {
2881			of_node_put(child);
2882			return -ENOMEM;
2883		}
2884
2885		ret = qcom_nand_host_init_and_register(nandc, host, child);
2886		if (ret) {
2887			devm_kfree(dev, host);
2888			continue;
2889		}
2890
2891		list_add_tail(&host->node, &nandc->host_list);
2892	}
2893
2894	return ret;
2895}
2896
2897/* parse custom DT properties here */
2898static int qcom_nandc_parse_dt(struct platform_device *pdev)
2899{
2900	struct qcom_nand_controller *nandc = platform_get_drvdata(pdev);
2901	struct device_node *np = nandc->dev->of_node;
2902	int ret;
2903
2904	if (!nandc->props->is_bam) {
2905		ret = of_property_read_u32(np, "qcom,cmd-crci",
2906					   &nandc->cmd_crci);
2907		if (ret) {
2908			dev_err(nandc->dev, "command CRCI unspecified\n");
2909			return ret;
2910		}
2911
2912		ret = of_property_read_u32(np, "qcom,data-crci",
2913					   &nandc->data_crci);
2914		if (ret) {
2915			dev_err(nandc->dev, "data CRCI unspecified\n");
2916			return ret;
2917		}
2918	}
2919
2920	return 0;
2921}
2922
2923static int qcom_nandc_probe(struct platform_device *pdev)
2924{
2925	struct qcom_nand_controller *nandc;
2926	const void *dev_data;
2927	struct device *dev = &pdev->dev;
2928	struct resource *res;
2929	int ret;
2930
2931	nandc = devm_kzalloc(&pdev->dev, sizeof(*nandc), GFP_KERNEL);
2932	if (!nandc)
2933		return -ENOMEM;
2934
2935	platform_set_drvdata(pdev, nandc);
2936	nandc->dev = dev;
2937
2938	dev_data = of_device_get_match_data(dev);
2939	if (!dev_data) {
2940		dev_err(&pdev->dev, "failed to get device data\n");
2941		return -ENODEV;
2942	}
2943
2944	nandc->props = dev_data;
2945
2946	nandc->core_clk = devm_clk_get(dev, "core");
2947	if (IS_ERR(nandc->core_clk))
2948		return PTR_ERR(nandc->core_clk);
2949
2950	nandc->aon_clk = devm_clk_get(dev, "aon");
2951	if (IS_ERR(nandc->aon_clk))
2952		return PTR_ERR(nandc->aon_clk);
2953
2954	ret = qcom_nandc_parse_dt(pdev);
2955	if (ret)
2956		return ret;
2957
2958	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
2959	nandc->base = devm_ioremap_resource(dev, res);
2960	if (IS_ERR(nandc->base))
2961		return PTR_ERR(nandc->base);
2962
2963	nandc->base_phys = res->start;
2964	nandc->base_dma = dma_map_resource(dev, res->start,
2965					   resource_size(res),
2966					   DMA_BIDIRECTIONAL, 0);
2967	if (!nandc->base_dma)
2968		return -ENXIO;
2969
2970	ret = clk_prepare_enable(nandc->core_clk);
2971	if (ret)
2972		goto err_core_clk;
2973
2974	ret = clk_prepare_enable(nandc->aon_clk);
2975	if (ret)
2976		goto err_aon_clk;
2977
2978	ret = qcom_nandc_alloc(nandc);
2979	if (ret)
2980		goto err_nandc_alloc;
2981
2982	ret = qcom_nandc_setup(nandc);
2983	if (ret)
2984		goto err_setup;
2985
2986	ret = qcom_probe_nand_devices(nandc);
2987	if (ret)
2988		goto err_setup;
2989
2990	return 0;
2991
2992err_setup:
2993	qcom_nandc_unalloc(nandc);
2994err_nandc_alloc:
2995	clk_disable_unprepare(nandc->aon_clk);
2996err_aon_clk:
2997	clk_disable_unprepare(nandc->core_clk);
2998err_core_clk:
2999	dma_unmap_resource(dev, nandc->base_dma, resource_size(res),
3000			   DMA_BIDIRECTIONAL, 0);
3001	return ret;
3002}
3003
3004static int qcom_nandc_remove(struct platform_device *pdev)
3005{
3006	struct qcom_nand_controller *nandc = platform_get_drvdata(pdev);
3007	struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
3008	struct qcom_nand_host *host;
3009	struct nand_chip *chip;
3010	int ret;
3011
3012	list_for_each_entry(host, &nandc->host_list, node) {
3013		chip = &host->chip;
3014		ret = mtd_device_unregister(nand_to_mtd(chip));
3015		WARN_ON(ret);
3016		nand_cleanup(chip);
3017	}
3018
3019	qcom_nandc_unalloc(nandc);
3020
3021	clk_disable_unprepare(nandc->aon_clk);
3022	clk_disable_unprepare(nandc->core_clk);
3023
3024	dma_unmap_resource(&pdev->dev, nandc->base_dma, resource_size(res),
3025			   DMA_BIDIRECTIONAL, 0);
3026
3027	return 0;
3028}
3029
3030static const struct qcom_nandc_props ipq806x_nandc_props = {
3031	.ecc_modes = (ECC_RS_4BIT | ECC_BCH_8BIT),
3032	.is_bam = false,
3033	.dev_cmd_reg_start = 0x0,
3034};
3035
3036static const struct qcom_nandc_props ipq4019_nandc_props = {
3037	.ecc_modes = (ECC_BCH_4BIT | ECC_BCH_8BIT),
3038	.is_bam = true,
3039	.is_qpic = true,
3040	.dev_cmd_reg_start = 0x0,
3041};
3042
3043static const struct qcom_nandc_props ipq8074_nandc_props = {
3044	.ecc_modes = (ECC_BCH_4BIT | ECC_BCH_8BIT),
3045	.is_bam = true,
3046	.is_qpic = true,
3047	.dev_cmd_reg_start = 0x7000,
3048};
3049
3050/*
3051 * data will hold a struct pointer containing more differences once we support
3052 * more controller variants
3053 */
3054static const struct of_device_id qcom_nandc_of_match[] = {
3055	{
3056		.compatible = "qcom,ipq806x-nand",
3057		.data = &ipq806x_nandc_props,
3058	},
3059	{
3060		.compatible = "qcom,ipq4019-nand",
3061		.data = &ipq4019_nandc_props,
3062	},
3063	{
3064		.compatible = "qcom,ipq8074-nand",
3065		.data = &ipq8074_nandc_props,
3066	},
3067	{}
3068};
3069MODULE_DEVICE_TABLE(of, qcom_nandc_of_match);
3070
3071static struct platform_driver qcom_nandc_driver = {
3072	.driver = {
3073		.name = "qcom-nandc",
3074		.of_match_table = qcom_nandc_of_match,
3075	},
3076	.probe   = qcom_nandc_probe,
3077	.remove  = qcom_nandc_remove,
3078};
3079module_platform_driver(qcom_nandc_driver);
3080
3081MODULE_AUTHOR("Archit Taneja <architt@codeaurora.org>");
3082MODULE_DESCRIPTION("Qualcomm NAND Controller driver");
3083MODULE_LICENSE("GPL v2");
3084