1// SPDX-License-Identifier: GPL-2.0
2/*
3 * PCIe driver for Marvell Armada 370 and Armada XP SoCs
4 *
5 * Author: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
6 */
7
8#include <linux/kernel.h>
9#include <linux/pci.h>
10#include <linux/clk.h>
11#include <linux/delay.h>
12#include <linux/gpio.h>
13#include <linux/init.h>
14#include <linux/mbus.h>
15#include <linux/slab.h>
16#include <linux/platform_device.h>
17#include <linux/of_address.h>
18#include <linux/of_irq.h>
19#include <linux/of_gpio.h>
20#include <linux/of_pci.h>
21#include <linux/of_platform.h>
22
23#include "../pci.h"
24#include "../pci-bridge-emul.h"
25
26/*
27 * PCIe unit register offsets.
28 */
29#define PCIE_DEV_ID_OFF		0x0000
30#define PCIE_CMD_OFF		0x0004
31#define PCIE_DEV_REV_OFF	0x0008
32#define PCIE_BAR_LO_OFF(n)	(0x0010 + ((n) << 3))
33#define PCIE_BAR_HI_OFF(n)	(0x0014 + ((n) << 3))
34#define PCIE_CAP_PCIEXP		0x0060
35#define PCIE_HEADER_LOG_4_OFF	0x0128
36#define PCIE_BAR_CTRL_OFF(n)	(0x1804 + (((n) - 1) * 4))
37#define PCIE_WIN04_CTRL_OFF(n)	(0x1820 + ((n) << 4))
38#define PCIE_WIN04_BASE_OFF(n)	(0x1824 + ((n) << 4))
39#define PCIE_WIN04_REMAP_OFF(n)	(0x182c + ((n) << 4))
40#define PCIE_WIN5_CTRL_OFF	0x1880
41#define PCIE_WIN5_BASE_OFF	0x1884
42#define PCIE_WIN5_REMAP_OFF	0x188c
43#define PCIE_CONF_ADDR_OFF	0x18f8
44#define  PCIE_CONF_ADDR_EN		0x80000000
45#define  PCIE_CONF_REG(r)		((((r) & 0xf00) << 16) | ((r) & 0xfc))
46#define  PCIE_CONF_BUS(b)		(((b) & 0xff) << 16)
47#define  PCIE_CONF_DEV(d)		(((d) & 0x1f) << 11)
48#define  PCIE_CONF_FUNC(f)		(((f) & 0x7) << 8)
49#define  PCIE_CONF_ADDR(bus, devfn, where) \
50	(PCIE_CONF_BUS(bus) | PCIE_CONF_DEV(PCI_SLOT(devfn))    | \
51	 PCIE_CONF_FUNC(PCI_FUNC(devfn)) | PCIE_CONF_REG(where) | \
52	 PCIE_CONF_ADDR_EN)
53#define PCIE_CONF_DATA_OFF	0x18fc
54#define PCIE_MASK_OFF		0x1910
55#define  PCIE_MASK_ENABLE_INTS          0x0f000000
56#define PCIE_CTRL_OFF		0x1a00
57#define  PCIE_CTRL_X1_MODE		0x0001
58#define PCIE_STAT_OFF		0x1a04
59#define  PCIE_STAT_BUS                  0xff00
60#define  PCIE_STAT_DEV                  0x1f0000
61#define  PCIE_STAT_LINK_DOWN		BIT(0)
62#define PCIE_RC_RTSTA		0x1a14
63#define PCIE_DEBUG_CTRL         0x1a60
64#define  PCIE_DEBUG_SOFT_RESET		BIT(20)
65
66struct mvebu_pcie_port;
67
68/* Structure representing all PCIe interfaces */
69struct mvebu_pcie {
70	struct platform_device *pdev;
71	struct mvebu_pcie_port *ports;
72	struct resource io;
73	struct resource realio;
74	struct resource mem;
75	struct resource busn;
76	int nports;
77};
78
79struct mvebu_pcie_window {
80	phys_addr_t base;
81	phys_addr_t remap;
82	size_t size;
83};
84
85/* Structure representing one PCIe interface */
86struct mvebu_pcie_port {
87	char *name;
88	void __iomem *base;
89	u32 port;
90	u32 lane;
91	int devfn;
92	unsigned int mem_target;
93	unsigned int mem_attr;
94	unsigned int io_target;
95	unsigned int io_attr;
96	struct clk *clk;
97	struct gpio_desc *reset_gpio;
98	char *reset_name;
99	struct pci_bridge_emul bridge;
100	struct device_node *dn;
101	struct mvebu_pcie *pcie;
102	struct mvebu_pcie_window memwin;
103	struct mvebu_pcie_window iowin;
104	u32 saved_pcie_stat;
105	struct resource regs;
106};
107
108static inline void mvebu_writel(struct mvebu_pcie_port *port, u32 val, u32 reg)
109{
110	writel(val, port->base + reg);
111}
112
113static inline u32 mvebu_readl(struct mvebu_pcie_port *port, u32 reg)
114{
115	return readl(port->base + reg);
116}
117
118static inline bool mvebu_has_ioport(struct mvebu_pcie_port *port)
119{
120	return port->io_target != -1 && port->io_attr != -1;
121}
122
123static bool mvebu_pcie_link_up(struct mvebu_pcie_port *port)
124{
125	return !(mvebu_readl(port, PCIE_STAT_OFF) & PCIE_STAT_LINK_DOWN);
126}
127
128static void mvebu_pcie_set_local_bus_nr(struct mvebu_pcie_port *port, int nr)
129{
130	u32 stat;
131
132	stat = mvebu_readl(port, PCIE_STAT_OFF);
133	stat &= ~PCIE_STAT_BUS;
134	stat |= nr << 8;
135	mvebu_writel(port, stat, PCIE_STAT_OFF);
136}
137
138static void mvebu_pcie_set_local_dev_nr(struct mvebu_pcie_port *port, int nr)
139{
140	u32 stat;
141
142	stat = mvebu_readl(port, PCIE_STAT_OFF);
143	stat &= ~PCIE_STAT_DEV;
144	stat |= nr << 16;
145	mvebu_writel(port, stat, PCIE_STAT_OFF);
146}
147
148/*
149 * Setup PCIE BARs and Address Decode Wins:
150 * BAR[0] -> internal registers (needed for MSI)
151 * BAR[1] -> covers all DRAM banks
152 * BAR[2] -> Disabled
153 * WIN[0-3] -> DRAM bank[0-3]
154 */
155static void mvebu_pcie_setup_wins(struct mvebu_pcie_port *port)
156{
157	const struct mbus_dram_target_info *dram;
158	u32 size;
159	int i;
160
161	dram = mv_mbus_dram_info();
162
163	/* First, disable and clear BARs and windows. */
164	for (i = 1; i < 3; i++) {
165		mvebu_writel(port, 0, PCIE_BAR_CTRL_OFF(i));
166		mvebu_writel(port, 0, PCIE_BAR_LO_OFF(i));
167		mvebu_writel(port, 0, PCIE_BAR_HI_OFF(i));
168	}
169
170	for (i = 0; i < 5; i++) {
171		mvebu_writel(port, 0, PCIE_WIN04_CTRL_OFF(i));
172		mvebu_writel(port, 0, PCIE_WIN04_BASE_OFF(i));
173		mvebu_writel(port, 0, PCIE_WIN04_REMAP_OFF(i));
174	}
175
176	mvebu_writel(port, 0, PCIE_WIN5_CTRL_OFF);
177	mvebu_writel(port, 0, PCIE_WIN5_BASE_OFF);
178	mvebu_writel(port, 0, PCIE_WIN5_REMAP_OFF);
179
180	/* Setup windows for DDR banks.  Count total DDR size on the fly. */
181	size = 0;
182	for (i = 0; i < dram->num_cs; i++) {
183		const struct mbus_dram_window *cs = dram->cs + i;
184
185		mvebu_writel(port, cs->base & 0xffff0000,
186			     PCIE_WIN04_BASE_OFF(i));
187		mvebu_writel(port, 0, PCIE_WIN04_REMAP_OFF(i));
188		mvebu_writel(port,
189			     ((cs->size - 1) & 0xffff0000) |
190			     (cs->mbus_attr << 8) |
191			     (dram->mbus_dram_target_id << 4) | 1,
192			     PCIE_WIN04_CTRL_OFF(i));
193
194		size += cs->size;
195	}
196
197	/* Round up 'size' to the nearest power of two. */
198	if ((size & (size - 1)) != 0)
199		size = 1 << fls(size);
200
201	/* Setup BAR[1] to all DRAM banks. */
202	mvebu_writel(port, dram->cs[0].base, PCIE_BAR_LO_OFF(1));
203	mvebu_writel(port, 0, PCIE_BAR_HI_OFF(1));
204	mvebu_writel(port, ((size - 1) & 0xffff0000) | 1,
205		     PCIE_BAR_CTRL_OFF(1));
206
207	/*
208	 * Point BAR[0] to the device's internal registers.
209	 */
210	mvebu_writel(port, round_down(port->regs.start, SZ_1M), PCIE_BAR_LO_OFF(0));
211	mvebu_writel(port, 0, PCIE_BAR_HI_OFF(0));
212}
213
214static void mvebu_pcie_setup_hw(struct mvebu_pcie_port *port)
215{
216	u32 cmd, mask;
217
218	/* Point PCIe unit MBUS decode windows to DRAM space. */
219	mvebu_pcie_setup_wins(port);
220
221	/* Master + slave enable. */
222	cmd = mvebu_readl(port, PCIE_CMD_OFF);
223	cmd |= PCI_COMMAND_IO;
224	cmd |= PCI_COMMAND_MEMORY;
225	cmd |= PCI_COMMAND_MASTER;
226	mvebu_writel(port, cmd, PCIE_CMD_OFF);
227
228	/* Enable interrupt lines A-D. */
229	mask = mvebu_readl(port, PCIE_MASK_OFF);
230	mask |= PCIE_MASK_ENABLE_INTS;
231	mvebu_writel(port, mask, PCIE_MASK_OFF);
232}
233
234static int mvebu_pcie_hw_rd_conf(struct mvebu_pcie_port *port,
235				 struct pci_bus *bus,
236				 u32 devfn, int where, int size, u32 *val)
237{
238	void __iomem *conf_data = port->base + PCIE_CONF_DATA_OFF;
239
240	mvebu_writel(port, PCIE_CONF_ADDR(bus->number, devfn, where),
241		     PCIE_CONF_ADDR_OFF);
242
243	switch (size) {
244	case 1:
245		*val = readb_relaxed(conf_data + (where & 3));
246		break;
247	case 2:
248		*val = readw_relaxed(conf_data + (where & 2));
249		break;
250	case 4:
251		*val = readl_relaxed(conf_data);
252		break;
253	}
254
255	return PCIBIOS_SUCCESSFUL;
256}
257
258static int mvebu_pcie_hw_wr_conf(struct mvebu_pcie_port *port,
259				 struct pci_bus *bus,
260				 u32 devfn, int where, int size, u32 val)
261{
262	void __iomem *conf_data = port->base + PCIE_CONF_DATA_OFF;
263
264	mvebu_writel(port, PCIE_CONF_ADDR(bus->number, devfn, where),
265		     PCIE_CONF_ADDR_OFF);
266
267	switch (size) {
268	case 1:
269		writeb(val, conf_data + (where & 3));
270		break;
271	case 2:
272		writew(val, conf_data + (where & 2));
273		break;
274	case 4:
275		writel(val, conf_data);
276		break;
277	default:
278		return PCIBIOS_BAD_REGISTER_NUMBER;
279	}
280
281	return PCIBIOS_SUCCESSFUL;
282}
283
284/*
285 * Remove windows, starting from the largest ones to the smallest
286 * ones.
287 */
288static void mvebu_pcie_del_windows(struct mvebu_pcie_port *port,
289				   phys_addr_t base, size_t size)
290{
291	while (size) {
292		size_t sz = 1 << (fls(size) - 1);
293
294		mvebu_mbus_del_window(base, sz);
295		base += sz;
296		size -= sz;
297	}
298}
299
300/*
301 * MBus windows can only have a power of two size, but PCI BARs do not
302 * have this constraint. Therefore, we have to split the PCI BAR into
303 * areas each having a power of two size. We start from the largest
304 * one (i.e highest order bit set in the size).
305 */
306static void mvebu_pcie_add_windows(struct mvebu_pcie_port *port,
307				   unsigned int target, unsigned int attribute,
308				   phys_addr_t base, size_t size,
309				   phys_addr_t remap)
310{
311	size_t size_mapped = 0;
312
313	while (size) {
314		size_t sz = 1 << (fls(size) - 1);
315		int ret;
316
317		ret = mvebu_mbus_add_window_remap_by_id(target, attribute, base,
318							sz, remap);
319		if (ret) {
320			phys_addr_t end = base + sz - 1;
321
322			dev_err(&port->pcie->pdev->dev,
323				"Could not create MBus window at [mem %pa-%pa]: %d\n",
324				&base, &end, ret);
325			mvebu_pcie_del_windows(port, base - size_mapped,
326					       size_mapped);
327			return;
328		}
329
330		size -= sz;
331		size_mapped += sz;
332		base += sz;
333		if (remap != MVEBU_MBUS_NO_REMAP)
334			remap += sz;
335	}
336}
337
338static void mvebu_pcie_set_window(struct mvebu_pcie_port *port,
339				  unsigned int target, unsigned int attribute,
340				  const struct mvebu_pcie_window *desired,
341				  struct mvebu_pcie_window *cur)
342{
343	if (desired->base == cur->base && desired->remap == cur->remap &&
344	    desired->size == cur->size)
345		return;
346
347	if (cur->size != 0) {
348		mvebu_pcie_del_windows(port, cur->base, cur->size);
349		cur->size = 0;
350		cur->base = 0;
351
352		/*
353		 * If something tries to change the window while it is enabled
354		 * the change will not be done atomically. That would be
355		 * difficult to do in the general case.
356		 */
357	}
358
359	if (desired->size == 0)
360		return;
361
362	mvebu_pcie_add_windows(port, target, attribute, desired->base,
363			       desired->size, desired->remap);
364	*cur = *desired;
365}
366
367static void mvebu_pcie_handle_iobase_change(struct mvebu_pcie_port *port)
368{
369	struct mvebu_pcie_window desired = {};
370	struct pci_bridge_emul_conf *conf = &port->bridge.conf;
371
372	/* Are the new iobase/iolimit values invalid? */
373	if (conf->iolimit < conf->iobase ||
374	    conf->iolimitupper < conf->iobaseupper ||
375	    !(conf->command & PCI_COMMAND_IO)) {
376		mvebu_pcie_set_window(port, port->io_target, port->io_attr,
377				      &desired, &port->iowin);
378		return;
379	}
380
381	if (!mvebu_has_ioport(port)) {
382		dev_WARN(&port->pcie->pdev->dev,
383			 "Attempt to set IO when IO is disabled\n");
384		return;
385	}
386
387	/*
388	 * We read the PCI-to-PCI bridge emulated registers, and
389	 * calculate the base address and size of the address decoding
390	 * window to setup, according to the PCI-to-PCI bridge
391	 * specifications. iobase is the bus address, port->iowin_base
392	 * is the CPU address.
393	 */
394	desired.remap = ((conf->iobase & 0xF0) << 8) |
395			(conf->iobaseupper << 16);
396	desired.base = port->pcie->io.start + desired.remap;
397	desired.size = ((0xFFF | ((conf->iolimit & 0xF0) << 8) |
398			 (conf->iolimitupper << 16)) -
399			desired.remap) +
400		       1;
401
402	mvebu_pcie_set_window(port, port->io_target, port->io_attr, &desired,
403			      &port->iowin);
404}
405
406static void mvebu_pcie_handle_membase_change(struct mvebu_pcie_port *port)
407{
408	struct mvebu_pcie_window desired = {.remap = MVEBU_MBUS_NO_REMAP};
409	struct pci_bridge_emul_conf *conf = &port->bridge.conf;
410
411	/* Are the new membase/memlimit values invalid? */
412	if (conf->memlimit < conf->membase ||
413	    !(conf->command & PCI_COMMAND_MEMORY)) {
414		mvebu_pcie_set_window(port, port->mem_target, port->mem_attr,
415				      &desired, &port->memwin);
416		return;
417	}
418
419	/*
420	 * We read the PCI-to-PCI bridge emulated registers, and
421	 * calculate the base address and size of the address decoding
422	 * window to setup, according to the PCI-to-PCI bridge
423	 * specifications.
424	 */
425	desired.base = ((conf->membase & 0xFFF0) << 16);
426	desired.size = (((conf->memlimit & 0xFFF0) << 16) | 0xFFFFF) -
427		       desired.base + 1;
428
429	mvebu_pcie_set_window(port, port->mem_target, port->mem_attr, &desired,
430			      &port->memwin);
431}
432
433static pci_bridge_emul_read_status_t
434mvebu_pci_bridge_emul_pcie_conf_read(struct pci_bridge_emul *bridge,
435				     int reg, u32 *value)
436{
437	struct mvebu_pcie_port *port = bridge->data;
438
439	switch (reg) {
440	case PCI_EXP_DEVCAP:
441		*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCAP);
442		break;
443
444	case PCI_EXP_DEVCTL:
445		*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL) &
446				 ~(PCI_EXP_DEVCTL_URRE | PCI_EXP_DEVCTL_FERE |
447				   PCI_EXP_DEVCTL_NFERE | PCI_EXP_DEVCTL_CERE);
448		break;
449
450	case PCI_EXP_LNKCAP:
451		/*
452		 * PCIe requires the clock power management capability to be
453		 * hard-wired to zero for downstream ports
454		 */
455		*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCAP) &
456			 ~PCI_EXP_LNKCAP_CLKPM;
457		break;
458
459	case PCI_EXP_LNKCTL:
460		*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL);
461		break;
462
463	case PCI_EXP_SLTCTL:
464		*value = PCI_EXP_SLTSTA_PDS << 16;
465		break;
466
467	case PCI_EXP_RTSTA:
468		*value = mvebu_readl(port, PCIE_RC_RTSTA);
469		break;
470
471	default:
472		return PCI_BRIDGE_EMUL_NOT_HANDLED;
473	}
474
475	return PCI_BRIDGE_EMUL_HANDLED;
476}
477
478static void
479mvebu_pci_bridge_emul_base_conf_write(struct pci_bridge_emul *bridge,
480				      int reg, u32 old, u32 new, u32 mask)
481{
482	struct mvebu_pcie_port *port = bridge->data;
483	struct pci_bridge_emul_conf *conf = &bridge->conf;
484
485	switch (reg) {
486	case PCI_COMMAND:
487	{
488		if (!mvebu_has_ioport(port))
489			conf->command &= ~PCI_COMMAND_IO;
490
491		if ((old ^ new) & PCI_COMMAND_IO)
492			mvebu_pcie_handle_iobase_change(port);
493		if ((old ^ new) & PCI_COMMAND_MEMORY)
494			mvebu_pcie_handle_membase_change(port);
495
496		break;
497	}
498
499	case PCI_IO_BASE:
500		/*
501		 * We keep bit 1 set, it is a read-only bit that
502		 * indicates we support 32 bits addressing for the
503		 * I/O
504		 */
505		conf->iobase |= PCI_IO_RANGE_TYPE_32;
506		conf->iolimit |= PCI_IO_RANGE_TYPE_32;
507		mvebu_pcie_handle_iobase_change(port);
508		break;
509
510	case PCI_MEMORY_BASE:
511		mvebu_pcie_handle_membase_change(port);
512		break;
513
514	case PCI_IO_BASE_UPPER16:
515		mvebu_pcie_handle_iobase_change(port);
516		break;
517
518	case PCI_PRIMARY_BUS:
519		mvebu_pcie_set_local_bus_nr(port, conf->secondary_bus);
520		break;
521
522	default:
523		break;
524	}
525}
526
527static void
528mvebu_pci_bridge_emul_pcie_conf_write(struct pci_bridge_emul *bridge,
529				      int reg, u32 old, u32 new, u32 mask)
530{
531	struct mvebu_pcie_port *port = bridge->data;
532
533	switch (reg) {
534	case PCI_EXP_DEVCTL:
535		/*
536		 * Armada370 data says these bits must always
537		 * be zero when in root complex mode.
538		 */
539		new &= ~(PCI_EXP_DEVCTL_URRE | PCI_EXP_DEVCTL_FERE |
540			 PCI_EXP_DEVCTL_NFERE | PCI_EXP_DEVCTL_CERE);
541
542		mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL);
543		break;
544
545	case PCI_EXP_LNKCTL:
546		/*
547		 * If we don't support CLKREQ, we must ensure that the
548		 * CLKREQ enable bit always reads zero.  Since we haven't
549		 * had this capability, and it's dependent on board wiring,
550		 * disable it for the time being.
551		 */
552		new &= ~PCI_EXP_LNKCTL_CLKREQ_EN;
553
554		mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL);
555		break;
556
557	case PCI_EXP_RTSTA:
558		mvebu_writel(port, new, PCIE_RC_RTSTA);
559		break;
560	}
561}
562
563static struct pci_bridge_emul_ops mvebu_pci_bridge_emul_ops = {
564	.write_base = mvebu_pci_bridge_emul_base_conf_write,
565	.read_pcie = mvebu_pci_bridge_emul_pcie_conf_read,
566	.write_pcie = mvebu_pci_bridge_emul_pcie_conf_write,
567};
568
569/*
570 * Initialize the configuration space of the PCI-to-PCI bridge
571 * associated with the given PCIe interface.
572 */
573static void mvebu_pci_bridge_emul_init(struct mvebu_pcie_port *port)
574{
575	struct pci_bridge_emul *bridge = &port->bridge;
576	u32 pcie_cap = mvebu_readl(port, PCIE_CAP_PCIEXP);
577	u8 pcie_cap_ver = ((pcie_cap >> 16) & PCI_EXP_FLAGS_VERS);
578
579	bridge->conf.vendor = PCI_VENDOR_ID_MARVELL;
580	bridge->conf.device = mvebu_readl(port, PCIE_DEV_ID_OFF) >> 16;
581	bridge->conf.class_revision =
582		mvebu_readl(port, PCIE_DEV_REV_OFF) & 0xff;
583
584	if (mvebu_has_ioport(port)) {
585		/* We support 32 bits I/O addressing */
586		bridge->conf.iobase = PCI_IO_RANGE_TYPE_32;
587		bridge->conf.iolimit = PCI_IO_RANGE_TYPE_32;
588	}
589
590	/*
591	 * Older mvebu hardware provides PCIe Capability structure only in
592	 * version 1. New hardware provides it in version 2.
593	 */
594	bridge->pcie_conf.cap = cpu_to_le16(pcie_cap_ver);
595
596	bridge->has_pcie = true;
597	bridge->data = port;
598	bridge->ops = &mvebu_pci_bridge_emul_ops;
599
600	pci_bridge_emul_init(bridge, PCI_BRIDGE_EMUL_NO_PREFETCHABLE_BAR);
601}
602
603static inline struct mvebu_pcie *sys_to_pcie(struct pci_sys_data *sys)
604{
605	return sys->private_data;
606}
607
608static struct mvebu_pcie_port *mvebu_pcie_find_port(struct mvebu_pcie *pcie,
609						    struct pci_bus *bus,
610						    int devfn)
611{
612	int i;
613
614	for (i = 0; i < pcie->nports; i++) {
615		struct mvebu_pcie_port *port = &pcie->ports[i];
616
617		if (bus->number == 0 && port->devfn == devfn)
618			return port;
619		if (bus->number != 0 &&
620		    bus->number >= port->bridge.conf.secondary_bus &&
621		    bus->number <= port->bridge.conf.subordinate_bus)
622			return port;
623	}
624
625	return NULL;
626}
627
628/* PCI configuration space write function */
629static int mvebu_pcie_wr_conf(struct pci_bus *bus, u32 devfn,
630			      int where, int size, u32 val)
631{
632	struct mvebu_pcie *pcie = bus->sysdata;
633	struct mvebu_pcie_port *port;
634	int ret;
635
636	port = mvebu_pcie_find_port(pcie, bus, devfn);
637	if (!port)
638		return PCIBIOS_DEVICE_NOT_FOUND;
639
640	/* Access the emulated PCI-to-PCI bridge */
641	if (bus->number == 0)
642		return pci_bridge_emul_conf_write(&port->bridge, where,
643						  size, val);
644
645	if (!mvebu_pcie_link_up(port))
646		return PCIBIOS_DEVICE_NOT_FOUND;
647
648	/* Access the real PCIe interface */
649	ret = mvebu_pcie_hw_wr_conf(port, bus, devfn,
650				    where, size, val);
651
652	return ret;
653}
654
655/* PCI configuration space read function */
656static int mvebu_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
657			      int size, u32 *val)
658{
659	struct mvebu_pcie *pcie = bus->sysdata;
660	struct mvebu_pcie_port *port;
661	int ret;
662
663	port = mvebu_pcie_find_port(pcie, bus, devfn);
664	if (!port) {
665		*val = 0xffffffff;
666		return PCIBIOS_DEVICE_NOT_FOUND;
667	}
668
669	/* Access the emulated PCI-to-PCI bridge */
670	if (bus->number == 0)
671		return pci_bridge_emul_conf_read(&port->bridge, where,
672						 size, val);
673
674	if (!mvebu_pcie_link_up(port)) {
675		*val = 0xffffffff;
676		return PCIBIOS_DEVICE_NOT_FOUND;
677	}
678
679	/* Access the real PCIe interface */
680	ret = mvebu_pcie_hw_rd_conf(port, bus, devfn,
681				    where, size, val);
682
683	return ret;
684}
685
686static struct pci_ops mvebu_pcie_ops = {
687	.read = mvebu_pcie_rd_conf,
688	.write = mvebu_pcie_wr_conf,
689};
690
691static resource_size_t mvebu_pcie_align_resource(struct pci_dev *dev,
692						 const struct resource *res,
693						 resource_size_t start,
694						 resource_size_t size,
695						 resource_size_t align)
696{
697	if (dev->bus->number != 0)
698		return start;
699
700	/*
701	 * On the PCI-to-PCI bridge side, the I/O windows must have at
702	 * least a 64 KB size and the memory windows must have at
703	 * least a 1 MB size. Moreover, MBus windows need to have a
704	 * base address aligned on their size, and their size must be
705	 * a power of two. This means that if the BAR doesn't have a
706	 * power of two size, several MBus windows will actually be
707	 * created. We need to ensure that the biggest MBus window
708	 * (which will be the first one) is aligned on its size, which
709	 * explains the rounddown_pow_of_two() being done here.
710	 */
711	if (res->flags & IORESOURCE_IO)
712		return round_up(start, max_t(resource_size_t, SZ_64K,
713					     rounddown_pow_of_two(size)));
714	else if (res->flags & IORESOURCE_MEM)
715		return round_up(start, max_t(resource_size_t, SZ_1M,
716					     rounddown_pow_of_two(size)));
717	else
718		return start;
719}
720
721static void __iomem *mvebu_pcie_map_registers(struct platform_device *pdev,
722					      struct device_node *np,
723					      struct mvebu_pcie_port *port)
724{
725	int ret = 0;
726
727	ret = of_address_to_resource(np, 0, &port->regs);
728	if (ret)
729		return (void __iomem *)ERR_PTR(ret);
730
731	return devm_ioremap_resource(&pdev->dev, &port->regs);
732}
733
734#define DT_FLAGS_TO_TYPE(flags)       (((flags) >> 24) & 0x03)
735#define    DT_TYPE_IO                 0x1
736#define    DT_TYPE_MEM32              0x2
737#define DT_CPUADDR_TO_TARGET(cpuaddr) (((cpuaddr) >> 56) & 0xFF)
738#define DT_CPUADDR_TO_ATTR(cpuaddr)   (((cpuaddr) >> 48) & 0xFF)
739
740static int mvebu_get_tgt_attr(struct device_node *np, int devfn,
741			      unsigned long type,
742			      unsigned int *tgt,
743			      unsigned int *attr)
744{
745	const int na = 3, ns = 2;
746	const __be32 *range;
747	int rlen, nranges, rangesz, pna, i;
748
749	*tgt = -1;
750	*attr = -1;
751
752	range = of_get_property(np, "ranges", &rlen);
753	if (!range)
754		return -EINVAL;
755
756	pna = of_n_addr_cells(np);
757	rangesz = pna + na + ns;
758	nranges = rlen / sizeof(__be32) / rangesz;
759
760	for (i = 0; i < nranges; i++, range += rangesz) {
761		u32 flags = of_read_number(range, 1);
762		u32 slot = of_read_number(range + 1, 1);
763		u64 cpuaddr = of_read_number(range + na, pna);
764		unsigned long rtype;
765
766		if (DT_FLAGS_TO_TYPE(flags) == DT_TYPE_IO)
767			rtype = IORESOURCE_IO;
768		else if (DT_FLAGS_TO_TYPE(flags) == DT_TYPE_MEM32)
769			rtype = IORESOURCE_MEM;
770		else
771			continue;
772
773		if (slot == PCI_SLOT(devfn) && type == rtype) {
774			*tgt = DT_CPUADDR_TO_TARGET(cpuaddr);
775			*attr = DT_CPUADDR_TO_ATTR(cpuaddr);
776			return 0;
777		}
778	}
779
780	return -ENOENT;
781}
782
783#ifdef CONFIG_PM_SLEEP
784static int mvebu_pcie_suspend(struct device *dev)
785{
786	struct mvebu_pcie *pcie;
787	int i;
788
789	pcie = dev_get_drvdata(dev);
790	for (i = 0; i < pcie->nports; i++) {
791		struct mvebu_pcie_port *port = pcie->ports + i;
792		port->saved_pcie_stat = mvebu_readl(port, PCIE_STAT_OFF);
793	}
794
795	return 0;
796}
797
798static int mvebu_pcie_resume(struct device *dev)
799{
800	struct mvebu_pcie *pcie;
801	int i;
802
803	pcie = dev_get_drvdata(dev);
804	for (i = 0; i < pcie->nports; i++) {
805		struct mvebu_pcie_port *port = pcie->ports + i;
806		mvebu_writel(port, port->saved_pcie_stat, PCIE_STAT_OFF);
807		mvebu_pcie_setup_hw(port);
808	}
809
810	return 0;
811}
812#endif
813
814static void mvebu_pcie_port_clk_put(void *data)
815{
816	struct mvebu_pcie_port *port = data;
817
818	clk_put(port->clk);
819}
820
821static int mvebu_pcie_parse_port(struct mvebu_pcie *pcie,
822	struct mvebu_pcie_port *port, struct device_node *child)
823{
824	struct device *dev = &pcie->pdev->dev;
825	enum of_gpio_flags flags;
826	int reset_gpio, ret;
827
828	port->pcie = pcie;
829
830	if (of_property_read_u32(child, "marvell,pcie-port", &port->port)) {
831		dev_warn(dev, "ignoring %pOF, missing pcie-port property\n",
832			 child);
833		goto skip;
834	}
835
836	if (of_property_read_u32(child, "marvell,pcie-lane", &port->lane))
837		port->lane = 0;
838
839	port->name = devm_kasprintf(dev, GFP_KERNEL, "pcie%d.%d", port->port,
840				    port->lane);
841	if (!port->name) {
842		ret = -ENOMEM;
843		goto err;
844	}
845
846	port->devfn = of_pci_get_devfn(child);
847	if (port->devfn < 0)
848		goto skip;
849
850	ret = mvebu_get_tgt_attr(dev->of_node, port->devfn, IORESOURCE_MEM,
851				 &port->mem_target, &port->mem_attr);
852	if (ret < 0) {
853		dev_err(dev, "%s: cannot get tgt/attr for mem window\n",
854			port->name);
855		goto skip;
856	}
857
858	if (resource_size(&pcie->io) != 0) {
859		mvebu_get_tgt_attr(dev->of_node, port->devfn, IORESOURCE_IO,
860				   &port->io_target, &port->io_attr);
861	} else {
862		port->io_target = -1;
863		port->io_attr = -1;
864	}
865
866	reset_gpio = of_get_named_gpio_flags(child, "reset-gpios", 0, &flags);
867	if (reset_gpio == -EPROBE_DEFER) {
868		ret = reset_gpio;
869		goto err;
870	}
871
872	if (gpio_is_valid(reset_gpio)) {
873		unsigned long gpio_flags;
874
875		port->reset_name = devm_kasprintf(dev, GFP_KERNEL, "%s-reset",
876						  port->name);
877		if (!port->reset_name) {
878			ret = -ENOMEM;
879			goto err;
880		}
881
882		if (flags & OF_GPIO_ACTIVE_LOW) {
883			dev_info(dev, "%pOF: reset gpio is active low\n",
884				 child);
885			gpio_flags = GPIOF_ACTIVE_LOW |
886				     GPIOF_OUT_INIT_LOW;
887		} else {
888			gpio_flags = GPIOF_OUT_INIT_HIGH;
889		}
890
891		ret = devm_gpio_request_one(dev, reset_gpio, gpio_flags,
892					    port->reset_name);
893		if (ret) {
894			if (ret == -EPROBE_DEFER)
895				goto err;
896			goto skip;
897		}
898
899		port->reset_gpio = gpio_to_desc(reset_gpio);
900	}
901
902	port->clk = of_clk_get_by_name(child, NULL);
903	if (IS_ERR(port->clk)) {
904		dev_err(dev, "%s: cannot get clock\n", port->name);
905		goto skip;
906	}
907
908	ret = devm_add_action(dev, mvebu_pcie_port_clk_put, port);
909	if (ret < 0) {
910		clk_put(port->clk);
911		goto err;
912	}
913
914	return 1;
915
916skip:
917	ret = 0;
918
919	/* In the case of skipping, we need to free these */
920	devm_kfree(dev, port->reset_name);
921	port->reset_name = NULL;
922	devm_kfree(dev, port->name);
923	port->name = NULL;
924
925err:
926	return ret;
927}
928
929/*
930 * Power up a PCIe port.  PCIe requires the refclk to be stable for 100µs
931 * prior to releasing PERST.  See table 2-4 in section 2.6.2 AC Specifications
932 * of the PCI Express Card Electromechanical Specification, 1.1.
933 */
934static int mvebu_pcie_powerup(struct mvebu_pcie_port *port)
935{
936	int ret;
937
938	ret = clk_prepare_enable(port->clk);
939	if (ret < 0)
940		return ret;
941
942	if (port->reset_gpio) {
943		u32 reset_udelay = PCI_PM_D3COLD_WAIT * 1000;
944
945		of_property_read_u32(port->dn, "reset-delay-us",
946				     &reset_udelay);
947
948		udelay(100);
949
950		gpiod_set_value_cansleep(port->reset_gpio, 0);
951		msleep(reset_udelay / 1000);
952	}
953
954	return 0;
955}
956
957/*
958 * Power down a PCIe port.  Strictly, PCIe requires us to place the card
959 * in D3hot state before asserting PERST#.
960 */
961static void mvebu_pcie_powerdown(struct mvebu_pcie_port *port)
962{
963	gpiod_set_value_cansleep(port->reset_gpio, 1);
964
965	clk_disable_unprepare(port->clk);
966}
967
968/*
969 * devm_of_pci_get_host_bridge_resources() only sets up translateable resources,
970 * so we need extra resource setup parsing our special DT properties encoding
971 * the MEM and IO apertures.
972 */
973static int mvebu_pcie_parse_request_resources(struct mvebu_pcie *pcie)
974{
975	struct device *dev = &pcie->pdev->dev;
976	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
977	int ret;
978
979	/* Get the PCIe memory aperture */
980	mvebu_mbus_get_pcie_mem_aperture(&pcie->mem);
981	if (resource_size(&pcie->mem) == 0) {
982		dev_err(dev, "invalid memory aperture size\n");
983		return -EINVAL;
984	}
985
986	pcie->mem.name = "PCI MEM";
987	pci_add_resource(&bridge->windows, &pcie->mem);
988	ret = devm_request_resource(dev, &iomem_resource, &pcie->mem);
989	if (ret)
990		return ret;
991
992	/* Get the PCIe IO aperture */
993	mvebu_mbus_get_pcie_io_aperture(&pcie->io);
994
995	if (resource_size(&pcie->io) != 0) {
996		pcie->realio.flags = pcie->io.flags;
997		pcie->realio.start = PCIBIOS_MIN_IO;
998		pcie->realio.end = min_t(resource_size_t,
999					 IO_SPACE_LIMIT - SZ_64K,
1000					 resource_size(&pcie->io) - 1);
1001		pcie->realio.name = "PCI I/O";
1002
1003		pci_add_resource(&bridge->windows, &pcie->realio);
1004		ret = devm_request_resource(dev, &ioport_resource, &pcie->realio);
1005		if (ret)
1006			return ret;
1007	}
1008
1009	return 0;
1010}
1011
1012/*
1013 * This is a copy of pci_host_probe(), except that it does the I/O
1014 * remap as the last step, once we are sure we won't fail.
1015 *
1016 * It should be removed once the I/O remap error handling issue has
1017 * been sorted out.
1018 */
1019static int mvebu_pci_host_probe(struct pci_host_bridge *bridge)
1020{
1021	struct mvebu_pcie *pcie;
1022	struct pci_bus *bus, *child;
1023	int ret;
1024
1025	ret = pci_scan_root_bus_bridge(bridge);
1026	if (ret < 0) {
1027		dev_err(bridge->dev.parent, "Scanning root bridge failed");
1028		return ret;
1029	}
1030
1031	pcie = pci_host_bridge_priv(bridge);
1032	if (resource_size(&pcie->io) != 0) {
1033		unsigned int i;
1034
1035		for (i = 0; i < resource_size(&pcie->realio); i += SZ_64K)
1036			pci_ioremap_io(i, pcie->io.start + i);
1037	}
1038
1039	bus = bridge->bus;
1040
1041	/*
1042	 * We insert PCI resources into the iomem_resource and
1043	 * ioport_resource trees in either pci_bus_claim_resources()
1044	 * or pci_bus_assign_resources().
1045	 */
1046	if (pci_has_flag(PCI_PROBE_ONLY)) {
1047		pci_bus_claim_resources(bus);
1048	} else {
1049		pci_bus_size_bridges(bus);
1050		pci_bus_assign_resources(bus);
1051
1052		list_for_each_entry(child, &bus->children, node)
1053			pcie_bus_configure_settings(child);
1054	}
1055
1056	pci_bus_add_devices(bus);
1057	return 0;
1058}
1059
1060static int mvebu_pcie_probe(struct platform_device *pdev)
1061{
1062	struct device *dev = &pdev->dev;
1063	struct mvebu_pcie *pcie;
1064	struct pci_host_bridge *bridge;
1065	struct device_node *np = dev->of_node;
1066	struct device_node *child;
1067	int num, i, ret;
1068
1069	bridge = devm_pci_alloc_host_bridge(dev, sizeof(struct mvebu_pcie));
1070	if (!bridge)
1071		return -ENOMEM;
1072
1073	pcie = pci_host_bridge_priv(bridge);
1074	pcie->pdev = pdev;
1075	platform_set_drvdata(pdev, pcie);
1076
1077	ret = mvebu_pcie_parse_request_resources(pcie);
1078	if (ret)
1079		return ret;
1080
1081	num = of_get_available_child_count(np);
1082
1083	pcie->ports = devm_kcalloc(dev, num, sizeof(*pcie->ports), GFP_KERNEL);
1084	if (!pcie->ports)
1085		return -ENOMEM;
1086
1087	i = 0;
1088	for_each_available_child_of_node(np, child) {
1089		struct mvebu_pcie_port *port = &pcie->ports[i];
1090
1091		ret = mvebu_pcie_parse_port(pcie, port, child);
1092		if (ret < 0) {
1093			of_node_put(child);
1094			return ret;
1095		} else if (ret == 0) {
1096			continue;
1097		}
1098
1099		port->dn = child;
1100		i++;
1101	}
1102	pcie->nports = i;
1103
1104	for (i = 0; i < pcie->nports; i++) {
1105		struct mvebu_pcie_port *port = &pcie->ports[i];
1106
1107		child = port->dn;
1108		if (!child)
1109			continue;
1110
1111		ret = mvebu_pcie_powerup(port);
1112		if (ret < 0)
1113			continue;
1114
1115		port->base = mvebu_pcie_map_registers(pdev, child, port);
1116		if (IS_ERR(port->base)) {
1117			dev_err(dev, "%s: cannot map registers\n", port->name);
1118			port->base = NULL;
1119			mvebu_pcie_powerdown(port);
1120			continue;
1121		}
1122
1123		mvebu_pcie_setup_hw(port);
1124		mvebu_pcie_set_local_dev_nr(port, 1);
1125		mvebu_pci_bridge_emul_init(port);
1126	}
1127
1128	pcie->nports = i;
1129
1130	bridge->sysdata = pcie;
1131	bridge->ops = &mvebu_pcie_ops;
1132	bridge->align_resource = mvebu_pcie_align_resource;
1133
1134	return mvebu_pci_host_probe(bridge);
1135}
1136
1137static const struct of_device_id mvebu_pcie_of_match_table[] = {
1138	{ .compatible = "marvell,armada-xp-pcie", },
1139	{ .compatible = "marvell,armada-370-pcie", },
1140	{ .compatible = "marvell,dove-pcie", },
1141	{ .compatible = "marvell,kirkwood-pcie", },
1142	{},
1143};
1144
1145static const struct dev_pm_ops mvebu_pcie_pm_ops = {
1146	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(mvebu_pcie_suspend, mvebu_pcie_resume)
1147};
1148
1149static struct platform_driver mvebu_pcie_driver = {
1150	.driver = {
1151		.name = "mvebu-pcie",
1152		.of_match_table = mvebu_pcie_of_match_table,
1153		/* driver unloading/unbinding currently not supported */
1154		.suppress_bind_attrs = true,
1155		.pm = &mvebu_pcie_pm_ops,
1156	},
1157	.probe = mvebu_pcie_probe,
1158};
1159builtin_platform_driver(mvebu_pcie_driver);
1160