1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2013-2014, The Linux Foundation. All rights reserved.
4 */
5/*
6 * QCOM BAM DMA engine driver
7 *
8 * QCOM BAM DMA blocks are distributed amongst a number of the on-chip
9 * peripherals on the MSM 8x74.  The configuration of the channels are dependent
10 * on the way they are hard wired to that specific peripheral.  The peripheral
11 * device tree entries specify the configuration of each channel.
12 *
13 * The DMA controller requires the use of external memory for storage of the
14 * hardware descriptors for each channel.  The descriptor FIFO is accessed as a
15 * circular buffer and operations are managed according to the offset within the
16 * FIFO.  After pipe/channel reset, all of the pipe registers and internal state
17 * are back to defaults.
18 *
19 * During DMA operations, we write descriptors to the FIFO, being careful to
20 * handle wrapping and then write the last FIFO offset to that channel's
21 * P_EVNT_REG register to kick off the transaction.  The P_SW_OFSTS register
22 * indicates the current FIFO offset that is being processed, so there is some
23 * indication of where the hardware is currently working.
24 */
25
26#include <linux/kernel.h>
27#include <linux/io.h>
28#include <linux/init.h>
29#include <linux/slab.h>
30#include <linux/module.h>
31#include <linux/interrupt.h>
32#include <linux/dma-mapping.h>
33#include <linux/scatterlist.h>
34#include <linux/device.h>
35#include <linux/platform_device.h>
36#include <linux/of.h>
37#include <linux/of_address.h>
38#include <linux/of_irq.h>
39#include <linux/of_dma.h>
40#include <linux/circ_buf.h>
41#include <linux/clk.h>
42#include <linux/dmaengine.h>
43#include <linux/pm_runtime.h>
44
45#include "../dmaengine.h"
46#include "../virt-dma.h"
47
48struct bam_desc_hw {
49	__le32 addr;		/* Buffer physical address */
50	__le16 size;		/* Buffer size in bytes */
51	__le16 flags;
52};
53
54#define BAM_DMA_AUTOSUSPEND_DELAY 100
55
56#define DESC_FLAG_INT BIT(15)
57#define DESC_FLAG_EOT BIT(14)
58#define DESC_FLAG_EOB BIT(13)
59#define DESC_FLAG_NWD BIT(12)
60#define DESC_FLAG_CMD BIT(11)
61
62struct bam_async_desc {
63	struct virt_dma_desc vd;
64
65	u32 num_desc;
66	u32 xfer_len;
67
68	/* transaction flags, EOT|EOB|NWD */
69	u16 flags;
70
71	struct bam_desc_hw *curr_desc;
72
73	/* list node for the desc in the bam_chan list of descriptors */
74	struct list_head desc_node;
75	enum dma_transfer_direction dir;
76	size_t length;
77	struct bam_desc_hw desc[];
78};
79
80enum bam_reg {
81	BAM_CTRL,
82	BAM_REVISION,
83	BAM_NUM_PIPES,
84	BAM_DESC_CNT_TRSHLD,
85	BAM_IRQ_SRCS,
86	BAM_IRQ_SRCS_MSK,
87	BAM_IRQ_SRCS_UNMASKED,
88	BAM_IRQ_STTS,
89	BAM_IRQ_CLR,
90	BAM_IRQ_EN,
91	BAM_CNFG_BITS,
92	BAM_IRQ_SRCS_EE,
93	BAM_IRQ_SRCS_MSK_EE,
94	BAM_P_CTRL,
95	BAM_P_RST,
96	BAM_P_HALT,
97	BAM_P_IRQ_STTS,
98	BAM_P_IRQ_CLR,
99	BAM_P_IRQ_EN,
100	BAM_P_EVNT_DEST_ADDR,
101	BAM_P_EVNT_REG,
102	BAM_P_SW_OFSTS,
103	BAM_P_DATA_FIFO_ADDR,
104	BAM_P_DESC_FIFO_ADDR,
105	BAM_P_EVNT_GEN_TRSHLD,
106	BAM_P_FIFO_SIZES,
107};
108
109struct reg_offset_data {
110	u32 base_offset;
111	unsigned int pipe_mult, evnt_mult, ee_mult;
112};
113
114static const struct reg_offset_data bam_v1_3_reg_info[] = {
115	[BAM_CTRL]		= { 0x0F80, 0x00, 0x00, 0x00 },
116	[BAM_REVISION]		= { 0x0F84, 0x00, 0x00, 0x00 },
117	[BAM_NUM_PIPES]		= { 0x0FBC, 0x00, 0x00, 0x00 },
118	[BAM_DESC_CNT_TRSHLD]	= { 0x0F88, 0x00, 0x00, 0x00 },
119	[BAM_IRQ_SRCS]		= { 0x0F8C, 0x00, 0x00, 0x00 },
120	[BAM_IRQ_SRCS_MSK]	= { 0x0F90, 0x00, 0x00, 0x00 },
121	[BAM_IRQ_SRCS_UNMASKED]	= { 0x0FB0, 0x00, 0x00, 0x00 },
122	[BAM_IRQ_STTS]		= { 0x0F94, 0x00, 0x00, 0x00 },
123	[BAM_IRQ_CLR]		= { 0x0F98, 0x00, 0x00, 0x00 },
124	[BAM_IRQ_EN]		= { 0x0F9C, 0x00, 0x00, 0x00 },
125	[BAM_CNFG_BITS]		= { 0x0FFC, 0x00, 0x00, 0x00 },
126	[BAM_IRQ_SRCS_EE]	= { 0x1800, 0x00, 0x00, 0x80 },
127	[BAM_IRQ_SRCS_MSK_EE]	= { 0x1804, 0x00, 0x00, 0x80 },
128	[BAM_P_CTRL]		= { 0x0000, 0x80, 0x00, 0x00 },
129	[BAM_P_RST]		= { 0x0004, 0x80, 0x00, 0x00 },
130	[BAM_P_HALT]		= { 0x0008, 0x80, 0x00, 0x00 },
131	[BAM_P_IRQ_STTS]	= { 0x0010, 0x80, 0x00, 0x00 },
132	[BAM_P_IRQ_CLR]		= { 0x0014, 0x80, 0x00, 0x00 },
133	[BAM_P_IRQ_EN]		= { 0x0018, 0x80, 0x00, 0x00 },
134	[BAM_P_EVNT_DEST_ADDR]	= { 0x102C, 0x00, 0x40, 0x00 },
135	[BAM_P_EVNT_REG]	= { 0x1018, 0x00, 0x40, 0x00 },
136	[BAM_P_SW_OFSTS]	= { 0x1000, 0x00, 0x40, 0x00 },
137	[BAM_P_DATA_FIFO_ADDR]	= { 0x1024, 0x00, 0x40, 0x00 },
138	[BAM_P_DESC_FIFO_ADDR]	= { 0x101C, 0x00, 0x40, 0x00 },
139	[BAM_P_EVNT_GEN_TRSHLD]	= { 0x1028, 0x00, 0x40, 0x00 },
140	[BAM_P_FIFO_SIZES]	= { 0x1020, 0x00, 0x40, 0x00 },
141};
142
143static const struct reg_offset_data bam_v1_4_reg_info[] = {
144	[BAM_CTRL]		= { 0x0000, 0x00, 0x00, 0x00 },
145	[BAM_REVISION]		= { 0x0004, 0x00, 0x00, 0x00 },
146	[BAM_NUM_PIPES]		= { 0x003C, 0x00, 0x00, 0x00 },
147	[BAM_DESC_CNT_TRSHLD]	= { 0x0008, 0x00, 0x00, 0x00 },
148	[BAM_IRQ_SRCS]		= { 0x000C, 0x00, 0x00, 0x00 },
149	[BAM_IRQ_SRCS_MSK]	= { 0x0010, 0x00, 0x00, 0x00 },
150	[BAM_IRQ_SRCS_UNMASKED]	= { 0x0030, 0x00, 0x00, 0x00 },
151	[BAM_IRQ_STTS]		= { 0x0014, 0x00, 0x00, 0x00 },
152	[BAM_IRQ_CLR]		= { 0x0018, 0x00, 0x00, 0x00 },
153	[BAM_IRQ_EN]		= { 0x001C, 0x00, 0x00, 0x00 },
154	[BAM_CNFG_BITS]		= { 0x007C, 0x00, 0x00, 0x00 },
155	[BAM_IRQ_SRCS_EE]	= { 0x0800, 0x00, 0x00, 0x80 },
156	[BAM_IRQ_SRCS_MSK_EE]	= { 0x0804, 0x00, 0x00, 0x80 },
157	[BAM_P_CTRL]		= { 0x1000, 0x1000, 0x00, 0x00 },
158	[BAM_P_RST]		= { 0x1004, 0x1000, 0x00, 0x00 },
159	[BAM_P_HALT]		= { 0x1008, 0x1000, 0x00, 0x00 },
160	[BAM_P_IRQ_STTS]	= { 0x1010, 0x1000, 0x00, 0x00 },
161	[BAM_P_IRQ_CLR]		= { 0x1014, 0x1000, 0x00, 0x00 },
162	[BAM_P_IRQ_EN]		= { 0x1018, 0x1000, 0x00, 0x00 },
163	[BAM_P_EVNT_DEST_ADDR]	= { 0x182C, 0x00, 0x1000, 0x00 },
164	[BAM_P_EVNT_REG]	= { 0x1818, 0x00, 0x1000, 0x00 },
165	[BAM_P_SW_OFSTS]	= { 0x1800, 0x00, 0x1000, 0x00 },
166	[BAM_P_DATA_FIFO_ADDR]	= { 0x1824, 0x00, 0x1000, 0x00 },
167	[BAM_P_DESC_FIFO_ADDR]	= { 0x181C, 0x00, 0x1000, 0x00 },
168	[BAM_P_EVNT_GEN_TRSHLD]	= { 0x1828, 0x00, 0x1000, 0x00 },
169	[BAM_P_FIFO_SIZES]	= { 0x1820, 0x00, 0x1000, 0x00 },
170};
171
172static const struct reg_offset_data bam_v1_7_reg_info[] = {
173	[BAM_CTRL]		= { 0x00000, 0x00, 0x00, 0x00 },
174	[BAM_REVISION]		= { 0x01000, 0x00, 0x00, 0x00 },
175	[BAM_NUM_PIPES]		= { 0x01008, 0x00, 0x00, 0x00 },
176	[BAM_DESC_CNT_TRSHLD]	= { 0x00008, 0x00, 0x00, 0x00 },
177	[BAM_IRQ_SRCS]		= { 0x03010, 0x00, 0x00, 0x00 },
178	[BAM_IRQ_SRCS_MSK]	= { 0x03014, 0x00, 0x00, 0x00 },
179	[BAM_IRQ_SRCS_UNMASKED]	= { 0x03018, 0x00, 0x00, 0x00 },
180	[BAM_IRQ_STTS]		= { 0x00014, 0x00, 0x00, 0x00 },
181	[BAM_IRQ_CLR]		= { 0x00018, 0x00, 0x00, 0x00 },
182	[BAM_IRQ_EN]		= { 0x0001C, 0x00, 0x00, 0x00 },
183	[BAM_CNFG_BITS]		= { 0x0007C, 0x00, 0x00, 0x00 },
184	[BAM_IRQ_SRCS_EE]	= { 0x03000, 0x00, 0x00, 0x1000 },
185	[BAM_IRQ_SRCS_MSK_EE]	= { 0x03004, 0x00, 0x00, 0x1000 },
186	[BAM_P_CTRL]		= { 0x13000, 0x1000, 0x00, 0x00 },
187	[BAM_P_RST]		= { 0x13004, 0x1000, 0x00, 0x00 },
188	[BAM_P_HALT]		= { 0x13008, 0x1000, 0x00, 0x00 },
189	[BAM_P_IRQ_STTS]	= { 0x13010, 0x1000, 0x00, 0x00 },
190	[BAM_P_IRQ_CLR]		= { 0x13014, 0x1000, 0x00, 0x00 },
191	[BAM_P_IRQ_EN]		= { 0x13018, 0x1000, 0x00, 0x00 },
192	[BAM_P_EVNT_DEST_ADDR]	= { 0x1382C, 0x00, 0x1000, 0x00 },
193	[BAM_P_EVNT_REG]	= { 0x13818, 0x00, 0x1000, 0x00 },
194	[BAM_P_SW_OFSTS]	= { 0x13800, 0x00, 0x1000, 0x00 },
195	[BAM_P_DATA_FIFO_ADDR]	= { 0x13824, 0x00, 0x1000, 0x00 },
196	[BAM_P_DESC_FIFO_ADDR]	= { 0x1381C, 0x00, 0x1000, 0x00 },
197	[BAM_P_EVNT_GEN_TRSHLD]	= { 0x13828, 0x00, 0x1000, 0x00 },
198	[BAM_P_FIFO_SIZES]	= { 0x13820, 0x00, 0x1000, 0x00 },
199};
200
201/* BAM CTRL */
202#define BAM_SW_RST			BIT(0)
203#define BAM_EN				BIT(1)
204#define BAM_EN_ACCUM			BIT(4)
205#define BAM_TESTBUS_SEL_SHIFT		5
206#define BAM_TESTBUS_SEL_MASK		0x3F
207#define BAM_DESC_CACHE_SEL_SHIFT	13
208#define BAM_DESC_CACHE_SEL_MASK		0x3
209#define BAM_CACHED_DESC_STORE		BIT(15)
210#define IBC_DISABLE			BIT(16)
211
212/* BAM REVISION */
213#define REVISION_SHIFT		0
214#define REVISION_MASK		0xFF
215#define NUM_EES_SHIFT		8
216#define NUM_EES_MASK		0xF
217#define CE_BUFFER_SIZE		BIT(13)
218#define AXI_ACTIVE		BIT(14)
219#define USE_VMIDMT		BIT(15)
220#define SECURED			BIT(16)
221#define BAM_HAS_NO_BYPASS	BIT(17)
222#define HIGH_FREQUENCY_BAM	BIT(18)
223#define INACTIV_TMRS_EXST	BIT(19)
224#define NUM_INACTIV_TMRS	BIT(20)
225#define DESC_CACHE_DEPTH_SHIFT	21
226#define DESC_CACHE_DEPTH_1	(0 << DESC_CACHE_DEPTH_SHIFT)
227#define DESC_CACHE_DEPTH_2	(1 << DESC_CACHE_DEPTH_SHIFT)
228#define DESC_CACHE_DEPTH_3	(2 << DESC_CACHE_DEPTH_SHIFT)
229#define DESC_CACHE_DEPTH_4	(3 << DESC_CACHE_DEPTH_SHIFT)
230#define CMD_DESC_EN		BIT(23)
231#define INACTIV_TMR_BASE_SHIFT	24
232#define INACTIV_TMR_BASE_MASK	0xFF
233
234/* BAM NUM PIPES */
235#define BAM_NUM_PIPES_SHIFT		0
236#define BAM_NUM_PIPES_MASK		0xFF
237#define PERIPH_NON_PIPE_GRP_SHIFT	16
238#define PERIPH_NON_PIP_GRP_MASK		0xFF
239#define BAM_NON_PIPE_GRP_SHIFT		24
240#define BAM_NON_PIPE_GRP_MASK		0xFF
241
242/* BAM CNFG BITS */
243#define BAM_PIPE_CNFG		BIT(2)
244#define BAM_FULL_PIPE		BIT(11)
245#define BAM_NO_EXT_P_RST	BIT(12)
246#define BAM_IBC_DISABLE		BIT(13)
247#define BAM_SB_CLK_REQ		BIT(14)
248#define BAM_PSM_CSW_REQ		BIT(15)
249#define BAM_PSM_P_RES		BIT(16)
250#define BAM_AU_P_RES		BIT(17)
251#define BAM_SI_P_RES		BIT(18)
252#define BAM_WB_P_RES		BIT(19)
253#define BAM_WB_BLK_CSW		BIT(20)
254#define BAM_WB_CSW_ACK_IDL	BIT(21)
255#define BAM_WB_RETR_SVPNT	BIT(22)
256#define BAM_WB_DSC_AVL_P_RST	BIT(23)
257#define BAM_REG_P_EN		BIT(24)
258#define BAM_PSM_P_HD_DATA	BIT(25)
259#define BAM_AU_ACCUMED		BIT(26)
260#define BAM_CMD_ENABLE		BIT(27)
261
262#define BAM_CNFG_BITS_DEFAULT	(BAM_PIPE_CNFG |	\
263				 BAM_NO_EXT_P_RST |	\
264				 BAM_IBC_DISABLE |	\
265				 BAM_SB_CLK_REQ |	\
266				 BAM_PSM_CSW_REQ |	\
267				 BAM_PSM_P_RES |	\
268				 BAM_AU_P_RES |		\
269				 BAM_SI_P_RES |		\
270				 BAM_WB_P_RES |		\
271				 BAM_WB_BLK_CSW |	\
272				 BAM_WB_CSW_ACK_IDL |	\
273				 BAM_WB_RETR_SVPNT |	\
274				 BAM_WB_DSC_AVL_P_RST |	\
275				 BAM_REG_P_EN |		\
276				 BAM_PSM_P_HD_DATA |	\
277				 BAM_AU_ACCUMED |	\
278				 BAM_CMD_ENABLE)
279
280/* PIPE CTRL */
281#define P_EN			BIT(1)
282#define P_DIRECTION		BIT(3)
283#define P_SYS_STRM		BIT(4)
284#define P_SYS_MODE		BIT(5)
285#define P_AUTO_EOB		BIT(6)
286#define P_AUTO_EOB_SEL_SHIFT	7
287#define P_AUTO_EOB_SEL_512	(0 << P_AUTO_EOB_SEL_SHIFT)
288#define P_AUTO_EOB_SEL_256	(1 << P_AUTO_EOB_SEL_SHIFT)
289#define P_AUTO_EOB_SEL_128	(2 << P_AUTO_EOB_SEL_SHIFT)
290#define P_AUTO_EOB_SEL_64	(3 << P_AUTO_EOB_SEL_SHIFT)
291#define P_PREFETCH_LIMIT_SHIFT	9
292#define P_PREFETCH_LIMIT_32	(0 << P_PREFETCH_LIMIT_SHIFT)
293#define P_PREFETCH_LIMIT_16	(1 << P_PREFETCH_LIMIT_SHIFT)
294#define P_PREFETCH_LIMIT_4	(2 << P_PREFETCH_LIMIT_SHIFT)
295#define P_WRITE_NWD		BIT(11)
296#define P_LOCK_GROUP_SHIFT	16
297#define P_LOCK_GROUP_MASK	0x1F
298
299/* BAM_DESC_CNT_TRSHLD */
300#define CNT_TRSHLD		0xffff
301#define DEFAULT_CNT_THRSHLD	0x4
302
303/* BAM_IRQ_SRCS */
304#define BAM_IRQ			BIT(31)
305#define P_IRQ			0x7fffffff
306
307/* BAM_IRQ_SRCS_MSK */
308#define BAM_IRQ_MSK		BAM_IRQ
309#define P_IRQ_MSK		P_IRQ
310
311/* BAM_IRQ_STTS */
312#define BAM_TIMER_IRQ		BIT(4)
313#define BAM_EMPTY_IRQ		BIT(3)
314#define BAM_ERROR_IRQ		BIT(2)
315#define BAM_HRESP_ERR_IRQ	BIT(1)
316
317/* BAM_IRQ_CLR */
318#define BAM_TIMER_CLR		BIT(4)
319#define BAM_EMPTY_CLR		BIT(3)
320#define BAM_ERROR_CLR		BIT(2)
321#define BAM_HRESP_ERR_CLR	BIT(1)
322
323/* BAM_IRQ_EN */
324#define BAM_TIMER_EN		BIT(4)
325#define BAM_EMPTY_EN		BIT(3)
326#define BAM_ERROR_EN		BIT(2)
327#define BAM_HRESP_ERR_EN	BIT(1)
328
329/* BAM_P_IRQ_EN */
330#define P_PRCSD_DESC_EN		BIT(0)
331#define P_TIMER_EN		BIT(1)
332#define P_WAKE_EN		BIT(2)
333#define P_OUT_OF_DESC_EN	BIT(3)
334#define P_ERR_EN		BIT(4)
335#define P_TRNSFR_END_EN		BIT(5)
336#define P_DEFAULT_IRQS_EN	(P_PRCSD_DESC_EN | P_ERR_EN | P_TRNSFR_END_EN)
337
338/* BAM_P_SW_OFSTS */
339#define P_SW_OFSTS_MASK		0xffff
340
341#define BAM_DESC_FIFO_SIZE	SZ_32K
342#define MAX_DESCRIPTORS (BAM_DESC_FIFO_SIZE / sizeof(struct bam_desc_hw) - 1)
343#define BAM_FIFO_SIZE	(SZ_32K - 8)
344#define IS_BUSY(chan)	(CIRC_SPACE(bchan->tail, bchan->head,\
345			 MAX_DESCRIPTORS + 1) == 0)
346
347struct bam_chan {
348	struct virt_dma_chan vc;
349
350	struct bam_device *bdev;
351
352	/* configuration from device tree */
353	u32 id;
354
355	/* runtime configuration */
356	struct dma_slave_config slave;
357
358	/* fifo storage */
359	struct bam_desc_hw *fifo_virt;
360	dma_addr_t fifo_phys;
361
362	/* fifo markers */
363	unsigned short head;		/* start of active descriptor entries */
364	unsigned short tail;		/* end of active descriptor entries */
365
366	unsigned int initialized;	/* is the channel hw initialized? */
367	unsigned int paused;		/* is the channel paused? */
368	unsigned int reconfigure;	/* new slave config? */
369	/* list of descriptors currently processed */
370	struct list_head desc_list;
371
372	struct list_head node;
373};
374
375static inline struct bam_chan *to_bam_chan(struct dma_chan *common)
376{
377	return container_of(common, struct bam_chan, vc.chan);
378}
379
380struct bam_device {
381	void __iomem *regs;
382	struct device *dev;
383	struct dma_device common;
384	struct bam_chan *channels;
385	u32 num_channels;
386	u32 num_ees;
387
388	/* execution environment ID, from DT */
389	u32 ee;
390	bool controlled_remotely;
391
392	const struct reg_offset_data *layout;
393
394	struct clk *bamclk;
395	int irq;
396
397	/* dma start transaction tasklet */
398	struct tasklet_struct task;
399};
400
401/**
402 * bam_addr - returns BAM register address
403 * @bdev: bam device
404 * @pipe: pipe instance (ignored when register doesn't have multiple instances)
405 * @reg:  register enum
406 */
407static inline void __iomem *bam_addr(struct bam_device *bdev, u32 pipe,
408		enum bam_reg reg)
409{
410	const struct reg_offset_data r = bdev->layout[reg];
411
412	return bdev->regs + r.base_offset +
413		r.pipe_mult * pipe +
414		r.evnt_mult * pipe +
415		r.ee_mult * bdev->ee;
416}
417
418/**
419 * bam_reset_channel - Reset individual BAM DMA channel
420 * @bchan: bam channel
421 *
422 * This function resets a specific BAM channel
423 */
424static void bam_reset_channel(struct bam_chan *bchan)
425{
426	struct bam_device *bdev = bchan->bdev;
427
428	lockdep_assert_held(&bchan->vc.lock);
429
430	/* reset channel */
431	writel_relaxed(1, bam_addr(bdev, bchan->id, BAM_P_RST));
432	writel_relaxed(0, bam_addr(bdev, bchan->id, BAM_P_RST));
433
434	/* don't allow cpu to reorder BAM register accesses done after this */
435	wmb();
436
437	/* make sure hw is initialized when channel is used the first time  */
438	bchan->initialized = 0;
439}
440
441/**
442 * bam_chan_init_hw - Initialize channel hardware
443 * @bchan: bam channel
444 * @dir: DMA transfer direction
445 *
446 * This function resets and initializes the BAM channel
447 */
448static void bam_chan_init_hw(struct bam_chan *bchan,
449	enum dma_transfer_direction dir)
450{
451	struct bam_device *bdev = bchan->bdev;
452	u32 val;
453
454	/* Reset the channel to clear internal state of the FIFO */
455	bam_reset_channel(bchan);
456
457	/*
458	 * write out 8 byte aligned address.  We have enough space for this
459	 * because we allocated 1 more descriptor (8 bytes) than we can use
460	 */
461	writel_relaxed(ALIGN(bchan->fifo_phys, sizeof(struct bam_desc_hw)),
462			bam_addr(bdev, bchan->id, BAM_P_DESC_FIFO_ADDR));
463	writel_relaxed(BAM_FIFO_SIZE,
464			bam_addr(bdev, bchan->id, BAM_P_FIFO_SIZES));
465
466	/* enable the per pipe interrupts, enable EOT, ERR, and INT irqs */
467	writel_relaxed(P_DEFAULT_IRQS_EN,
468			bam_addr(bdev, bchan->id, BAM_P_IRQ_EN));
469
470	/* unmask the specific pipe and EE combo */
471	val = readl_relaxed(bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE));
472	val |= BIT(bchan->id);
473	writel_relaxed(val, bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE));
474
475	/* don't allow cpu to reorder the channel enable done below */
476	wmb();
477
478	/* set fixed direction and mode, then enable channel */
479	val = P_EN | P_SYS_MODE;
480	if (dir == DMA_DEV_TO_MEM)
481		val |= P_DIRECTION;
482
483	writel_relaxed(val, bam_addr(bdev, bchan->id, BAM_P_CTRL));
484
485	bchan->initialized = 1;
486
487	/* init FIFO pointers */
488	bchan->head = 0;
489	bchan->tail = 0;
490}
491
492/**
493 * bam_alloc_chan - Allocate channel resources for DMA channel.
494 * @chan: specified channel
495 *
496 * This function allocates the FIFO descriptor memory
497 */
498static int bam_alloc_chan(struct dma_chan *chan)
499{
500	struct bam_chan *bchan = to_bam_chan(chan);
501	struct bam_device *bdev = bchan->bdev;
502
503	if (bchan->fifo_virt)
504		return 0;
505
506	/* allocate FIFO descriptor space, but only if necessary */
507	bchan->fifo_virt = dma_alloc_wc(bdev->dev, BAM_DESC_FIFO_SIZE,
508					&bchan->fifo_phys, GFP_KERNEL);
509
510	if (!bchan->fifo_virt) {
511		dev_err(bdev->dev, "Failed to allocate desc fifo\n");
512		return -ENOMEM;
513	}
514
515	return 0;
516}
517
518static int bam_pm_runtime_get_sync(struct device *dev)
519{
520	if (pm_runtime_enabled(dev))
521		return pm_runtime_get_sync(dev);
522
523	return 0;
524}
525
526/**
527 * bam_free_chan - Frees dma resources associated with specific channel
528 * @chan: specified channel
529 *
530 * Free the allocated fifo descriptor memory and channel resources
531 *
532 */
533static void bam_free_chan(struct dma_chan *chan)
534{
535	struct bam_chan *bchan = to_bam_chan(chan);
536	struct bam_device *bdev = bchan->bdev;
537	u32 val;
538	unsigned long flags;
539	int ret;
540
541	ret = bam_pm_runtime_get_sync(bdev->dev);
542	if (ret < 0)
543		return;
544
545	vchan_free_chan_resources(to_virt_chan(chan));
546
547	if (!list_empty(&bchan->desc_list)) {
548		dev_err(bchan->bdev->dev, "Cannot free busy channel\n");
549		goto err;
550	}
551
552	spin_lock_irqsave(&bchan->vc.lock, flags);
553	bam_reset_channel(bchan);
554	spin_unlock_irqrestore(&bchan->vc.lock, flags);
555
556	dma_free_wc(bdev->dev, BAM_DESC_FIFO_SIZE, bchan->fifo_virt,
557		    bchan->fifo_phys);
558	bchan->fifo_virt = NULL;
559
560	/* mask irq for pipe/channel */
561	val = readl_relaxed(bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE));
562	val &= ~BIT(bchan->id);
563	writel_relaxed(val, bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE));
564
565	/* disable irq */
566	writel_relaxed(0, bam_addr(bdev, bchan->id, BAM_P_IRQ_EN));
567
568err:
569	pm_runtime_mark_last_busy(bdev->dev);
570	pm_runtime_put_autosuspend(bdev->dev);
571}
572
573/**
574 * bam_slave_config - set slave configuration for channel
575 * @chan: dma channel
576 * @cfg: slave configuration
577 *
578 * Sets slave configuration for channel
579 *
580 */
581static int bam_slave_config(struct dma_chan *chan,
582			    struct dma_slave_config *cfg)
583{
584	struct bam_chan *bchan = to_bam_chan(chan);
585	unsigned long flag;
586
587	spin_lock_irqsave(&bchan->vc.lock, flag);
588	memcpy(&bchan->slave, cfg, sizeof(*cfg));
589	bchan->reconfigure = 1;
590	spin_unlock_irqrestore(&bchan->vc.lock, flag);
591
592	return 0;
593}
594
595/**
596 * bam_prep_slave_sg - Prep slave sg transaction
597 *
598 * @chan: dma channel
599 * @sgl: scatter gather list
600 * @sg_len: length of sg
601 * @direction: DMA transfer direction
602 * @flags: DMA flags
603 * @context: transfer context (unused)
604 */
605static struct dma_async_tx_descriptor *bam_prep_slave_sg(struct dma_chan *chan,
606	struct scatterlist *sgl, unsigned int sg_len,
607	enum dma_transfer_direction direction, unsigned long flags,
608	void *context)
609{
610	struct bam_chan *bchan = to_bam_chan(chan);
611	struct bam_device *bdev = bchan->bdev;
612	struct bam_async_desc *async_desc;
613	struct scatterlist *sg;
614	u32 i;
615	struct bam_desc_hw *desc;
616	unsigned int num_alloc = 0;
617
618
619	if (!is_slave_direction(direction)) {
620		dev_err(bdev->dev, "invalid dma direction\n");
621		return NULL;
622	}
623
624	/* calculate number of required entries */
625	for_each_sg(sgl, sg, sg_len, i)
626		num_alloc += DIV_ROUND_UP(sg_dma_len(sg), BAM_FIFO_SIZE);
627
628	/* allocate enough room to accomodate the number of entries */
629	async_desc = kzalloc(struct_size(async_desc, desc, num_alloc),
630			     GFP_NOWAIT);
631
632	if (!async_desc)
633		goto err_out;
634
635	if (flags & DMA_PREP_FENCE)
636		async_desc->flags |= DESC_FLAG_NWD;
637
638	if (flags & DMA_PREP_INTERRUPT)
639		async_desc->flags |= DESC_FLAG_EOT;
640
641	async_desc->num_desc = num_alloc;
642	async_desc->curr_desc = async_desc->desc;
643	async_desc->dir = direction;
644
645	/* fill in temporary descriptors */
646	desc = async_desc->desc;
647	for_each_sg(sgl, sg, sg_len, i) {
648		unsigned int remainder = sg_dma_len(sg);
649		unsigned int curr_offset = 0;
650
651		do {
652			if (flags & DMA_PREP_CMD)
653				desc->flags |= cpu_to_le16(DESC_FLAG_CMD);
654
655			desc->addr = cpu_to_le32(sg_dma_address(sg) +
656						 curr_offset);
657
658			if (remainder > BAM_FIFO_SIZE) {
659				desc->size = cpu_to_le16(BAM_FIFO_SIZE);
660				remainder -= BAM_FIFO_SIZE;
661				curr_offset += BAM_FIFO_SIZE;
662			} else {
663				desc->size = cpu_to_le16(remainder);
664				remainder = 0;
665			}
666
667			async_desc->length += le16_to_cpu(desc->size);
668			desc++;
669		} while (remainder > 0);
670	}
671
672	return vchan_tx_prep(&bchan->vc, &async_desc->vd, flags);
673
674err_out:
675	kfree(async_desc);
676	return NULL;
677}
678
679/**
680 * bam_dma_terminate_all - terminate all transactions on a channel
681 * @chan: bam dma channel
682 *
683 * Dequeues and frees all transactions
684 * No callbacks are done
685 *
686 */
687static int bam_dma_terminate_all(struct dma_chan *chan)
688{
689	struct bam_chan *bchan = to_bam_chan(chan);
690	struct bam_async_desc *async_desc, *tmp;
691	unsigned long flag;
692	LIST_HEAD(head);
693
694	/* remove all transactions, including active transaction */
695	spin_lock_irqsave(&bchan->vc.lock, flag);
696	/*
697	 * If we have transactions queued, then some might be committed to the
698	 * hardware in the desc fifo.  The only way to reset the desc fifo is
699	 * to do a hardware reset (either by pipe or the entire block).
700	 * bam_chan_init_hw() will trigger a pipe reset, and also reinit the
701	 * pipe.  If the pipe is left disabled (default state after pipe reset)
702	 * and is accessed by a connected hardware engine, a fatal error in
703	 * the BAM will occur.  There is a small window where this could happen
704	 * with bam_chan_init_hw(), but it is assumed that the caller has
705	 * stopped activity on any attached hardware engine.  Make sure to do
706	 * this first so that the BAM hardware doesn't cause memory corruption
707	 * by accessing freed resources.
708	 */
709	if (!list_empty(&bchan->desc_list)) {
710		async_desc = list_first_entry(&bchan->desc_list,
711					      struct bam_async_desc, desc_node);
712		bam_chan_init_hw(bchan, async_desc->dir);
713	}
714
715	list_for_each_entry_safe(async_desc, tmp,
716				 &bchan->desc_list, desc_node) {
717		list_add(&async_desc->vd.node, &bchan->vc.desc_issued);
718		list_del(&async_desc->desc_node);
719	}
720
721	vchan_get_all_descriptors(&bchan->vc, &head);
722	spin_unlock_irqrestore(&bchan->vc.lock, flag);
723
724	vchan_dma_desc_free_list(&bchan->vc, &head);
725
726	return 0;
727}
728
729/**
730 * bam_pause - Pause DMA channel
731 * @chan: dma channel
732 *
733 */
734static int bam_pause(struct dma_chan *chan)
735{
736	struct bam_chan *bchan = to_bam_chan(chan);
737	struct bam_device *bdev = bchan->bdev;
738	unsigned long flag;
739	int ret;
740
741	ret = bam_pm_runtime_get_sync(bdev->dev);
742	if (ret < 0)
743		return ret;
744
745	spin_lock_irqsave(&bchan->vc.lock, flag);
746	writel_relaxed(1, bam_addr(bdev, bchan->id, BAM_P_HALT));
747	bchan->paused = 1;
748	spin_unlock_irqrestore(&bchan->vc.lock, flag);
749	pm_runtime_mark_last_busy(bdev->dev);
750	pm_runtime_put_autosuspend(bdev->dev);
751
752	return 0;
753}
754
755/**
756 * bam_resume - Resume DMA channel operations
757 * @chan: dma channel
758 *
759 */
760static int bam_resume(struct dma_chan *chan)
761{
762	struct bam_chan *bchan = to_bam_chan(chan);
763	struct bam_device *bdev = bchan->bdev;
764	unsigned long flag;
765	int ret;
766
767	ret = bam_pm_runtime_get_sync(bdev->dev);
768	if (ret < 0)
769		return ret;
770
771	spin_lock_irqsave(&bchan->vc.lock, flag);
772	writel_relaxed(0, bam_addr(bdev, bchan->id, BAM_P_HALT));
773	bchan->paused = 0;
774	spin_unlock_irqrestore(&bchan->vc.lock, flag);
775	pm_runtime_mark_last_busy(bdev->dev);
776	pm_runtime_put_autosuspend(bdev->dev);
777
778	return 0;
779}
780
781/**
782 * process_channel_irqs - processes the channel interrupts
783 * @bdev: bam controller
784 *
785 * This function processes the channel interrupts
786 *
787 */
788static u32 process_channel_irqs(struct bam_device *bdev)
789{
790	u32 i, srcs, pipe_stts, offset, avail;
791	unsigned long flags;
792	struct bam_async_desc *async_desc, *tmp;
793
794	srcs = readl_relaxed(bam_addr(bdev, 0, BAM_IRQ_SRCS_EE));
795
796	/* return early if no pipe/channel interrupts are present */
797	if (!(srcs & P_IRQ))
798		return srcs;
799
800	for (i = 0; i < bdev->num_channels; i++) {
801		struct bam_chan *bchan = &bdev->channels[i];
802
803		if (!(srcs & BIT(i)))
804			continue;
805
806		/* clear pipe irq */
807		pipe_stts = readl_relaxed(bam_addr(bdev, i, BAM_P_IRQ_STTS));
808
809		writel_relaxed(pipe_stts, bam_addr(bdev, i, BAM_P_IRQ_CLR));
810
811		spin_lock_irqsave(&bchan->vc.lock, flags);
812
813		offset = readl_relaxed(bam_addr(bdev, i, BAM_P_SW_OFSTS)) &
814				       P_SW_OFSTS_MASK;
815		offset /= sizeof(struct bam_desc_hw);
816
817		/* Number of bytes available to read */
818		avail = CIRC_CNT(offset, bchan->head, MAX_DESCRIPTORS + 1);
819
820		if (offset < bchan->head)
821			avail--;
822
823		list_for_each_entry_safe(async_desc, tmp,
824					 &bchan->desc_list, desc_node) {
825			/* Not enough data to read */
826			if (avail < async_desc->xfer_len)
827				break;
828
829			/* manage FIFO */
830			bchan->head += async_desc->xfer_len;
831			bchan->head %= MAX_DESCRIPTORS;
832
833			async_desc->num_desc -= async_desc->xfer_len;
834			async_desc->curr_desc += async_desc->xfer_len;
835			avail -= async_desc->xfer_len;
836
837			/*
838			 * if complete, process cookie. Otherwise
839			 * push back to front of desc_issued so that
840			 * it gets restarted by the tasklet
841			 */
842			if (!async_desc->num_desc) {
843				vchan_cookie_complete(&async_desc->vd);
844			} else {
845				list_add(&async_desc->vd.node,
846					 &bchan->vc.desc_issued);
847			}
848			list_del(&async_desc->desc_node);
849		}
850
851		spin_unlock_irqrestore(&bchan->vc.lock, flags);
852	}
853
854	return srcs;
855}
856
857/**
858 * bam_dma_irq - irq handler for bam controller
859 * @irq: IRQ of interrupt
860 * @data: callback data
861 *
862 * IRQ handler for the bam controller
863 */
864static irqreturn_t bam_dma_irq(int irq, void *data)
865{
866	struct bam_device *bdev = data;
867	u32 clr_mask = 0, srcs = 0;
868	int ret;
869
870	srcs |= process_channel_irqs(bdev);
871
872	/* kick off tasklet to start next dma transfer */
873	if (srcs & P_IRQ)
874		tasklet_schedule(&bdev->task);
875
876	ret = bam_pm_runtime_get_sync(bdev->dev);
877	if (ret < 0)
878		return ret;
879
880	if (srcs & BAM_IRQ) {
881		clr_mask = readl_relaxed(bam_addr(bdev, 0, BAM_IRQ_STTS));
882
883		/*
884		 * don't allow reorder of the various accesses to the BAM
885		 * registers
886		 */
887		mb();
888
889		writel_relaxed(clr_mask, bam_addr(bdev, 0, BAM_IRQ_CLR));
890	}
891
892	pm_runtime_mark_last_busy(bdev->dev);
893	pm_runtime_put_autosuspend(bdev->dev);
894
895	return IRQ_HANDLED;
896}
897
898/**
899 * bam_tx_status - returns status of transaction
900 * @chan: dma channel
901 * @cookie: transaction cookie
902 * @txstate: DMA transaction state
903 *
904 * Return status of dma transaction
905 */
906static enum dma_status bam_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
907		struct dma_tx_state *txstate)
908{
909	struct bam_chan *bchan = to_bam_chan(chan);
910	struct bam_async_desc *async_desc;
911	struct virt_dma_desc *vd;
912	int ret;
913	size_t residue = 0;
914	unsigned int i;
915	unsigned long flags;
916
917	ret = dma_cookie_status(chan, cookie, txstate);
918	if (ret == DMA_COMPLETE)
919		return ret;
920
921	if (!txstate)
922		return bchan->paused ? DMA_PAUSED : ret;
923
924	spin_lock_irqsave(&bchan->vc.lock, flags);
925	vd = vchan_find_desc(&bchan->vc, cookie);
926	if (vd) {
927		residue = container_of(vd, struct bam_async_desc, vd)->length;
928	} else {
929		list_for_each_entry(async_desc, &bchan->desc_list, desc_node) {
930			if (async_desc->vd.tx.cookie != cookie)
931				continue;
932
933			for (i = 0; i < async_desc->num_desc; i++)
934				residue += le16_to_cpu(
935						async_desc->curr_desc[i].size);
936		}
937	}
938
939	spin_unlock_irqrestore(&bchan->vc.lock, flags);
940
941	dma_set_residue(txstate, residue);
942
943	if (ret == DMA_IN_PROGRESS && bchan->paused)
944		ret = DMA_PAUSED;
945
946	return ret;
947}
948
949/**
950 * bam_apply_new_config
951 * @bchan: bam dma channel
952 * @dir: DMA direction
953 */
954static void bam_apply_new_config(struct bam_chan *bchan,
955	enum dma_transfer_direction dir)
956{
957	struct bam_device *bdev = bchan->bdev;
958	u32 maxburst;
959
960	if (!bdev->controlled_remotely) {
961		if (dir == DMA_DEV_TO_MEM)
962			maxburst = bchan->slave.src_maxburst;
963		else
964			maxburst = bchan->slave.dst_maxburst;
965
966		writel_relaxed(maxburst,
967			       bam_addr(bdev, 0, BAM_DESC_CNT_TRSHLD));
968	}
969
970	bchan->reconfigure = 0;
971}
972
973/**
974 * bam_start_dma - start next transaction
975 * @bchan: bam dma channel
976 */
977static void bam_start_dma(struct bam_chan *bchan)
978{
979	struct virt_dma_desc *vd = vchan_next_desc(&bchan->vc);
980	struct bam_device *bdev = bchan->bdev;
981	struct bam_async_desc *async_desc = NULL;
982	struct bam_desc_hw *desc;
983	struct bam_desc_hw *fifo = PTR_ALIGN(bchan->fifo_virt,
984					sizeof(struct bam_desc_hw));
985	int ret;
986	unsigned int avail;
987	struct dmaengine_desc_callback cb;
988
989	lockdep_assert_held(&bchan->vc.lock);
990
991	if (!vd)
992		return;
993
994	ret = bam_pm_runtime_get_sync(bdev->dev);
995	if (ret < 0)
996		return;
997
998	while (vd && !IS_BUSY(bchan)) {
999		list_del(&vd->node);
1000
1001		async_desc = container_of(vd, struct bam_async_desc, vd);
1002
1003		/* on first use, initialize the channel hardware */
1004		if (!bchan->initialized)
1005			bam_chan_init_hw(bchan, async_desc->dir);
1006
1007		/* apply new slave config changes, if necessary */
1008		if (bchan->reconfigure)
1009			bam_apply_new_config(bchan, async_desc->dir);
1010
1011		desc = async_desc->curr_desc;
1012		avail = CIRC_SPACE(bchan->tail, bchan->head,
1013				   MAX_DESCRIPTORS + 1);
1014
1015		if (async_desc->num_desc > avail)
1016			async_desc->xfer_len = avail;
1017		else
1018			async_desc->xfer_len = async_desc->num_desc;
1019
1020		/* set any special flags on the last descriptor */
1021		if (async_desc->num_desc == async_desc->xfer_len)
1022			desc[async_desc->xfer_len - 1].flags |=
1023						cpu_to_le16(async_desc->flags);
1024
1025		vd = vchan_next_desc(&bchan->vc);
1026
1027		dmaengine_desc_get_callback(&async_desc->vd.tx, &cb);
1028
1029		/*
1030		 * An interrupt is generated at this desc, if
1031		 *  - FIFO is FULL.
1032		 *  - No more descriptors to add.
1033		 *  - If a callback completion was requested for this DESC,
1034		 *     In this case, BAM will deliver the completion callback
1035		 *     for this desc and continue processing the next desc.
1036		 */
1037		if (((avail <= async_desc->xfer_len) || !vd ||
1038		     dmaengine_desc_callback_valid(&cb)) &&
1039		    !(async_desc->flags & DESC_FLAG_EOT))
1040			desc[async_desc->xfer_len - 1].flags |=
1041				cpu_to_le16(DESC_FLAG_INT);
1042
1043		if (bchan->tail + async_desc->xfer_len > MAX_DESCRIPTORS) {
1044			u32 partial = MAX_DESCRIPTORS - bchan->tail;
1045
1046			memcpy(&fifo[bchan->tail], desc,
1047			       partial * sizeof(struct bam_desc_hw));
1048			memcpy(fifo, &desc[partial],
1049			       (async_desc->xfer_len - partial) *
1050				sizeof(struct bam_desc_hw));
1051		} else {
1052			memcpy(&fifo[bchan->tail], desc,
1053			       async_desc->xfer_len *
1054			       sizeof(struct bam_desc_hw));
1055		}
1056
1057		bchan->tail += async_desc->xfer_len;
1058		bchan->tail %= MAX_DESCRIPTORS;
1059		list_add_tail(&async_desc->desc_node, &bchan->desc_list);
1060	}
1061
1062	/* ensure descriptor writes and dma start not reordered */
1063	wmb();
1064	writel_relaxed(bchan->tail * sizeof(struct bam_desc_hw),
1065			bam_addr(bdev, bchan->id, BAM_P_EVNT_REG));
1066
1067	pm_runtime_mark_last_busy(bdev->dev);
1068	pm_runtime_put_autosuspend(bdev->dev);
1069}
1070
1071/**
1072 * dma_tasklet - DMA IRQ tasklet
1073 * @t: tasklet argument (bam controller structure)
1074 *
1075 * Sets up next DMA operation and then processes all completed transactions
1076 */
1077static void dma_tasklet(struct tasklet_struct *t)
1078{
1079	struct bam_device *bdev = from_tasklet(bdev, t, task);
1080	struct bam_chan *bchan;
1081	unsigned long flags;
1082	unsigned int i;
1083
1084	/* go through the channels and kick off transactions */
1085	for (i = 0; i < bdev->num_channels; i++) {
1086		bchan = &bdev->channels[i];
1087		spin_lock_irqsave(&bchan->vc.lock, flags);
1088
1089		if (!list_empty(&bchan->vc.desc_issued) && !IS_BUSY(bchan))
1090			bam_start_dma(bchan);
1091		spin_unlock_irqrestore(&bchan->vc.lock, flags);
1092	}
1093
1094}
1095
1096/**
1097 * bam_issue_pending - starts pending transactions
1098 * @chan: dma channel
1099 *
1100 * Calls tasklet directly which in turn starts any pending transactions
1101 */
1102static void bam_issue_pending(struct dma_chan *chan)
1103{
1104	struct bam_chan *bchan = to_bam_chan(chan);
1105	unsigned long flags;
1106
1107	spin_lock_irqsave(&bchan->vc.lock, flags);
1108
1109	/* if work pending and idle, start a transaction */
1110	if (vchan_issue_pending(&bchan->vc) && !IS_BUSY(bchan))
1111		bam_start_dma(bchan);
1112
1113	spin_unlock_irqrestore(&bchan->vc.lock, flags);
1114}
1115
1116/**
1117 * bam_dma_free_desc - free descriptor memory
1118 * @vd: virtual descriptor
1119 *
1120 */
1121static void bam_dma_free_desc(struct virt_dma_desc *vd)
1122{
1123	struct bam_async_desc *async_desc = container_of(vd,
1124			struct bam_async_desc, vd);
1125
1126	kfree(async_desc);
1127}
1128
1129static struct dma_chan *bam_dma_xlate(struct of_phandle_args *dma_spec,
1130		struct of_dma *of)
1131{
1132	struct bam_device *bdev = container_of(of->of_dma_data,
1133					struct bam_device, common);
1134	unsigned int request;
1135
1136	if (dma_spec->args_count != 1)
1137		return NULL;
1138
1139	request = dma_spec->args[0];
1140	if (request >= bdev->num_channels)
1141		return NULL;
1142
1143	return dma_get_slave_channel(&(bdev->channels[request].vc.chan));
1144}
1145
1146/**
1147 * bam_init
1148 * @bdev: bam device
1149 *
1150 * Initialization helper for global bam registers
1151 */
1152static int bam_init(struct bam_device *bdev)
1153{
1154	u32 val;
1155
1156	/* read revision and configuration information */
1157	if (!bdev->num_ees) {
1158		val = readl_relaxed(bam_addr(bdev, 0, BAM_REVISION));
1159		bdev->num_ees = (val >> NUM_EES_SHIFT) & NUM_EES_MASK;
1160	}
1161
1162	/* check that configured EE is within range */
1163	if (bdev->ee >= bdev->num_ees)
1164		return -EINVAL;
1165
1166	if (!bdev->num_channels) {
1167		val = readl_relaxed(bam_addr(bdev, 0, BAM_NUM_PIPES));
1168		bdev->num_channels = val & BAM_NUM_PIPES_MASK;
1169	}
1170
1171	if (bdev->controlled_remotely)
1172		return 0;
1173
1174	/* s/w reset bam */
1175	/* after reset all pipes are disabled and idle */
1176	val = readl_relaxed(bam_addr(bdev, 0, BAM_CTRL));
1177	val |= BAM_SW_RST;
1178	writel_relaxed(val, bam_addr(bdev, 0, BAM_CTRL));
1179	val &= ~BAM_SW_RST;
1180	writel_relaxed(val, bam_addr(bdev, 0, BAM_CTRL));
1181
1182	/* make sure previous stores are visible before enabling BAM */
1183	wmb();
1184
1185	/* enable bam */
1186	val |= BAM_EN;
1187	writel_relaxed(val, bam_addr(bdev, 0, BAM_CTRL));
1188
1189	/* set descriptor threshhold, start with 4 bytes */
1190	writel_relaxed(DEFAULT_CNT_THRSHLD,
1191			bam_addr(bdev, 0, BAM_DESC_CNT_TRSHLD));
1192
1193	/* Enable default set of h/w workarounds, ie all except BAM_FULL_PIPE */
1194	writel_relaxed(BAM_CNFG_BITS_DEFAULT, bam_addr(bdev, 0, BAM_CNFG_BITS));
1195
1196	/* enable irqs for errors */
1197	writel_relaxed(BAM_ERROR_EN | BAM_HRESP_ERR_EN,
1198			bam_addr(bdev, 0, BAM_IRQ_EN));
1199
1200	/* unmask global bam interrupt */
1201	writel_relaxed(BAM_IRQ_MSK, bam_addr(bdev, 0, BAM_IRQ_SRCS_MSK_EE));
1202
1203	return 0;
1204}
1205
1206static void bam_channel_init(struct bam_device *bdev, struct bam_chan *bchan,
1207	u32 index)
1208{
1209	bchan->id = index;
1210	bchan->bdev = bdev;
1211
1212	vchan_init(&bchan->vc, &bdev->common);
1213	bchan->vc.desc_free = bam_dma_free_desc;
1214	INIT_LIST_HEAD(&bchan->desc_list);
1215}
1216
1217static const struct of_device_id bam_of_match[] = {
1218	{ .compatible = "qcom,bam-v1.3.0", .data = &bam_v1_3_reg_info },
1219	{ .compatible = "qcom,bam-v1.4.0", .data = &bam_v1_4_reg_info },
1220	{ .compatible = "qcom,bam-v1.7.0", .data = &bam_v1_7_reg_info },
1221	{}
1222};
1223
1224MODULE_DEVICE_TABLE(of, bam_of_match);
1225
1226static int bam_dma_probe(struct platform_device *pdev)
1227{
1228	struct bam_device *bdev;
1229	const struct of_device_id *match;
1230	struct resource *iores;
1231	int ret, i;
1232
1233	bdev = devm_kzalloc(&pdev->dev, sizeof(*bdev), GFP_KERNEL);
1234	if (!bdev)
1235		return -ENOMEM;
1236
1237	bdev->dev = &pdev->dev;
1238
1239	match = of_match_node(bam_of_match, pdev->dev.of_node);
1240	if (!match) {
1241		dev_err(&pdev->dev, "Unsupported BAM module\n");
1242		return -ENODEV;
1243	}
1244
1245	bdev->layout = match->data;
1246
1247	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1248	bdev->regs = devm_ioremap_resource(&pdev->dev, iores);
1249	if (IS_ERR(bdev->regs))
1250		return PTR_ERR(bdev->regs);
1251
1252	bdev->irq = platform_get_irq(pdev, 0);
1253	if (bdev->irq < 0)
1254		return bdev->irq;
1255
1256	ret = of_property_read_u32(pdev->dev.of_node, "qcom,ee", &bdev->ee);
1257	if (ret) {
1258		dev_err(bdev->dev, "Execution environment unspecified\n");
1259		return ret;
1260	}
1261
1262	bdev->controlled_remotely = of_property_read_bool(pdev->dev.of_node,
1263						"qcom,controlled-remotely");
1264
1265	if (bdev->controlled_remotely) {
1266		ret = of_property_read_u32(pdev->dev.of_node, "num-channels",
1267					   &bdev->num_channels);
1268		if (ret)
1269			dev_err(bdev->dev, "num-channels unspecified in dt\n");
1270
1271		ret = of_property_read_u32(pdev->dev.of_node, "qcom,num-ees",
1272					   &bdev->num_ees);
1273		if (ret)
1274			dev_err(bdev->dev, "num-ees unspecified in dt\n");
1275	}
1276
1277	bdev->bamclk = devm_clk_get(bdev->dev, "bam_clk");
1278	if (IS_ERR(bdev->bamclk)) {
1279		if (!bdev->controlled_remotely)
1280			return PTR_ERR(bdev->bamclk);
1281
1282		bdev->bamclk = NULL;
1283	}
1284
1285	ret = clk_prepare_enable(bdev->bamclk);
1286	if (ret) {
1287		dev_err(bdev->dev, "failed to prepare/enable clock\n");
1288		return ret;
1289	}
1290
1291	ret = bam_init(bdev);
1292	if (ret)
1293		goto err_disable_clk;
1294
1295	tasklet_setup(&bdev->task, dma_tasklet);
1296
1297	bdev->channels = devm_kcalloc(bdev->dev, bdev->num_channels,
1298				sizeof(*bdev->channels), GFP_KERNEL);
1299
1300	if (!bdev->channels) {
1301		ret = -ENOMEM;
1302		goto err_tasklet_kill;
1303	}
1304
1305	/* allocate and initialize channels */
1306	INIT_LIST_HEAD(&bdev->common.channels);
1307
1308	for (i = 0; i < bdev->num_channels; i++)
1309		bam_channel_init(bdev, &bdev->channels[i], i);
1310
1311	ret = devm_request_irq(bdev->dev, bdev->irq, bam_dma_irq,
1312			IRQF_TRIGGER_HIGH, "bam_dma", bdev);
1313	if (ret)
1314		goto err_bam_channel_exit;
1315
1316	/* set max dma segment size */
1317	bdev->common.dev = bdev->dev;
1318	ret = dma_set_max_seg_size(bdev->common.dev, BAM_FIFO_SIZE);
1319	if (ret) {
1320		dev_err(bdev->dev, "cannot set maximum segment size\n");
1321		goto err_bam_channel_exit;
1322	}
1323
1324	platform_set_drvdata(pdev, bdev);
1325
1326	/* set capabilities */
1327	dma_cap_zero(bdev->common.cap_mask);
1328	dma_cap_set(DMA_SLAVE, bdev->common.cap_mask);
1329
1330	/* initialize dmaengine apis */
1331	bdev->common.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
1332	bdev->common.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
1333	bdev->common.src_addr_widths = DMA_SLAVE_BUSWIDTH_4_BYTES;
1334	bdev->common.dst_addr_widths = DMA_SLAVE_BUSWIDTH_4_BYTES;
1335	bdev->common.device_alloc_chan_resources = bam_alloc_chan;
1336	bdev->common.device_free_chan_resources = bam_free_chan;
1337	bdev->common.device_prep_slave_sg = bam_prep_slave_sg;
1338	bdev->common.device_config = bam_slave_config;
1339	bdev->common.device_pause = bam_pause;
1340	bdev->common.device_resume = bam_resume;
1341	bdev->common.device_terminate_all = bam_dma_terminate_all;
1342	bdev->common.device_issue_pending = bam_issue_pending;
1343	bdev->common.device_tx_status = bam_tx_status;
1344	bdev->common.dev = bdev->dev;
1345
1346	ret = dma_async_device_register(&bdev->common);
1347	if (ret) {
1348		dev_err(bdev->dev, "failed to register dma async device\n");
1349		goto err_bam_channel_exit;
1350	}
1351
1352	ret = of_dma_controller_register(pdev->dev.of_node, bam_dma_xlate,
1353					&bdev->common);
1354	if (ret)
1355		goto err_unregister_dma;
1356
1357	if (bdev->controlled_remotely) {
1358		pm_runtime_disable(&pdev->dev);
1359		return 0;
1360	}
1361
1362	pm_runtime_irq_safe(&pdev->dev);
1363	pm_runtime_set_autosuspend_delay(&pdev->dev, BAM_DMA_AUTOSUSPEND_DELAY);
1364	pm_runtime_use_autosuspend(&pdev->dev);
1365	pm_runtime_mark_last_busy(&pdev->dev);
1366	pm_runtime_set_active(&pdev->dev);
1367	pm_runtime_enable(&pdev->dev);
1368
1369	return 0;
1370
1371err_unregister_dma:
1372	dma_async_device_unregister(&bdev->common);
1373err_bam_channel_exit:
1374	for (i = 0; i < bdev->num_channels; i++)
1375		tasklet_kill(&bdev->channels[i].vc.task);
1376err_tasklet_kill:
1377	tasklet_kill(&bdev->task);
1378err_disable_clk:
1379	clk_disable_unprepare(bdev->bamclk);
1380
1381	return ret;
1382}
1383
1384static int bam_dma_remove(struct platform_device *pdev)
1385{
1386	struct bam_device *bdev = platform_get_drvdata(pdev);
1387	u32 i;
1388
1389	pm_runtime_force_suspend(&pdev->dev);
1390
1391	of_dma_controller_free(pdev->dev.of_node);
1392	dma_async_device_unregister(&bdev->common);
1393
1394	/* mask all interrupts for this execution environment */
1395	writel_relaxed(0, bam_addr(bdev, 0,  BAM_IRQ_SRCS_MSK_EE));
1396
1397	devm_free_irq(bdev->dev, bdev->irq, bdev);
1398
1399	for (i = 0; i < bdev->num_channels; i++) {
1400		bam_dma_terminate_all(&bdev->channels[i].vc.chan);
1401		tasklet_kill(&bdev->channels[i].vc.task);
1402
1403		if (!bdev->channels[i].fifo_virt)
1404			continue;
1405
1406		dma_free_wc(bdev->dev, BAM_DESC_FIFO_SIZE,
1407			    bdev->channels[i].fifo_virt,
1408			    bdev->channels[i].fifo_phys);
1409	}
1410
1411	tasklet_kill(&bdev->task);
1412
1413	clk_disable_unprepare(bdev->bamclk);
1414
1415	return 0;
1416}
1417
1418static int __maybe_unused bam_dma_runtime_suspend(struct device *dev)
1419{
1420	struct bam_device *bdev = dev_get_drvdata(dev);
1421
1422	clk_disable(bdev->bamclk);
1423
1424	return 0;
1425}
1426
1427static int __maybe_unused bam_dma_runtime_resume(struct device *dev)
1428{
1429	struct bam_device *bdev = dev_get_drvdata(dev);
1430	int ret;
1431
1432	ret = clk_enable(bdev->bamclk);
1433	if (ret < 0) {
1434		dev_err(dev, "clk_enable failed: %d\n", ret);
1435		return ret;
1436	}
1437
1438	return 0;
1439}
1440
1441static int __maybe_unused bam_dma_suspend(struct device *dev)
1442{
1443	struct bam_device *bdev = dev_get_drvdata(dev);
1444
1445	if (!bdev->controlled_remotely)
1446		pm_runtime_force_suspend(dev);
1447
1448	clk_unprepare(bdev->bamclk);
1449
1450	return 0;
1451}
1452
1453static int __maybe_unused bam_dma_resume(struct device *dev)
1454{
1455	struct bam_device *bdev = dev_get_drvdata(dev);
1456	int ret;
1457
1458	ret = clk_prepare(bdev->bamclk);
1459	if (ret)
1460		return ret;
1461
1462	if (!bdev->controlled_remotely)
1463		pm_runtime_force_resume(dev);
1464
1465	return 0;
1466}
1467
1468static const struct dev_pm_ops bam_dma_pm_ops = {
1469	SET_LATE_SYSTEM_SLEEP_PM_OPS(bam_dma_suspend, bam_dma_resume)
1470	SET_RUNTIME_PM_OPS(bam_dma_runtime_suspend, bam_dma_runtime_resume,
1471				NULL)
1472};
1473
1474static struct platform_driver bam_dma_driver = {
1475	.probe = bam_dma_probe,
1476	.remove = bam_dma_remove,
1477	.driver = {
1478		.name = "bam-dma-engine",
1479		.pm = &bam_dma_pm_ops,
1480		.of_match_table = bam_of_match,
1481	},
1482};
1483
1484module_platform_driver(bam_dma_driver);
1485
1486MODULE_AUTHOR("Andy Gross <agross@codeaurora.org>");
1487MODULE_DESCRIPTION("QCOM BAM DMA engine driver");
1488MODULE_LICENSE("GPL v2");
1489