1/*
2 * PCIe driver for Marvell Armada 370 and Armada XP SoCs
3 *
4 * This file is licensed under the terms of the GNU General Public
5 * License version 2.  This program is licensed "as is" without any
6 * warranty of any kind, whether express or implied.
7 */
8
9#include <linux/kernel.h>
10#include <linux/pci.h>
11#include <linux/clk.h>
12#include <linux/delay.h>
13#include <linux/gpio.h>
14#include <linux/module.h>
15#include <linux/mbus.h>
16#include <linux/msi.h>
17#include <linux/slab.h>
18#include <linux/platform_device.h>
19#include <linux/of_address.h>
20#include <linux/of_irq.h>
21#include <linux/of_gpio.h>
22#include <linux/of_pci.h>
23#include <linux/of_platform.h>
24
25/*
26 * PCIe unit register offsets.
27 */
28#define PCIE_DEV_ID_OFF		0x0000
29#define PCIE_CMD_OFF		0x0004
30#define PCIE_DEV_REV_OFF	0x0008
31#define PCIE_BAR_LO_OFF(n)	(0x0010 + ((n) << 3))
32#define PCIE_BAR_HI_OFF(n)	(0x0014 + ((n) << 3))
33#define PCIE_HEADER_LOG_4_OFF	0x0128
34#define PCIE_BAR_CTRL_OFF(n)	(0x1804 + (((n) - 1) * 4))
35#define PCIE_WIN04_CTRL_OFF(n)	(0x1820 + ((n) << 4))
36#define PCIE_WIN04_BASE_OFF(n)	(0x1824 + ((n) << 4))
37#define PCIE_WIN04_REMAP_OFF(n)	(0x182c + ((n) << 4))
38#define PCIE_WIN5_CTRL_OFF	0x1880
39#define PCIE_WIN5_BASE_OFF	0x1884
40#define PCIE_WIN5_REMAP_OFF	0x188c
41#define PCIE_CONF_ADDR_OFF	0x18f8
42#define  PCIE_CONF_ADDR_EN		0x80000000
43#define  PCIE_CONF_REG(r)		((((r) & 0xf00) << 16) | ((r) & 0xfc))
44#define  PCIE_CONF_BUS(b)		(((b) & 0xff) << 16)
45#define  PCIE_CONF_DEV(d)		(((d) & 0x1f) << 11)
46#define  PCIE_CONF_FUNC(f)		(((f) & 0x7) << 8)
47#define  PCIE_CONF_ADDR(bus, devfn, where) \
48	(PCIE_CONF_BUS(bus) | PCIE_CONF_DEV(PCI_SLOT(devfn))    | \
49	 PCIE_CONF_FUNC(PCI_FUNC(devfn)) | PCIE_CONF_REG(where) | \
50	 PCIE_CONF_ADDR_EN)
51#define PCIE_CONF_DATA_OFF	0x18fc
52#define PCIE_MASK_OFF		0x1910
53#define  PCIE_MASK_ENABLE_INTS          0x0f000000
54#define PCIE_CTRL_OFF		0x1a00
55#define  PCIE_CTRL_X1_MODE		0x0001
56#define PCIE_STAT_OFF		0x1a04
57#define  PCIE_STAT_BUS                  0xff00
58#define  PCIE_STAT_DEV                  0x1f0000
59#define  PCIE_STAT_LINK_DOWN		BIT(0)
60#define PCIE_DEBUG_CTRL         0x1a60
61#define  PCIE_DEBUG_SOFT_RESET		BIT(20)
62
63/* PCI configuration space of a PCI-to-PCI bridge */
64struct mvebu_sw_pci_bridge {
65	u16 vendor;
66	u16 device;
67	u16 command;
68	u16 class;
69	u8 interface;
70	u8 revision;
71	u8 bist;
72	u8 header_type;
73	u8 latency_timer;
74	u8 cache_line_size;
75	u32 bar[2];
76	u8 primary_bus;
77	u8 secondary_bus;
78	u8 subordinate_bus;
79	u8 secondary_latency_timer;
80	u8 iobase;
81	u8 iolimit;
82	u16 secondary_status;
83	u16 membase;
84	u16 memlimit;
85	u16 iobaseupper;
86	u16 iolimitupper;
87	u8 cappointer;
88	u8 reserved1;
89	u16 reserved2;
90	u32 romaddr;
91	u8 intline;
92	u8 intpin;
93	u16 bridgectrl;
94};
95
96struct mvebu_pcie_port;
97
98/* Structure representing all PCIe interfaces */
99struct mvebu_pcie {
100	struct platform_device *pdev;
101	struct mvebu_pcie_port *ports;
102	struct msi_chip *msi;
103	struct resource io;
104	char io_name[30];
105	struct resource realio;
106	char mem_name[30];
107	struct resource mem;
108	struct resource busn;
109	int nports;
110};
111
112/* Structure representing one PCIe interface */
113struct mvebu_pcie_port {
114	char *name;
115	void __iomem *base;
116	u32 port;
117	u32 lane;
118	int devfn;
119	unsigned int mem_target;
120	unsigned int mem_attr;
121	unsigned int io_target;
122	unsigned int io_attr;
123	struct clk *clk;
124	int reset_gpio;
125	int reset_active_low;
126	char *reset_name;
127	struct mvebu_sw_pci_bridge bridge;
128	struct device_node *dn;
129	struct mvebu_pcie *pcie;
130	phys_addr_t memwin_base;
131	size_t memwin_size;
132	phys_addr_t iowin_base;
133	size_t iowin_size;
134};
135
136static inline void mvebu_writel(struct mvebu_pcie_port *port, u32 val, u32 reg)
137{
138	writel(val, port->base + reg);
139}
140
141static inline u32 mvebu_readl(struct mvebu_pcie_port *port, u32 reg)
142{
143	return readl(port->base + reg);
144}
145
146static inline bool mvebu_has_ioport(struct mvebu_pcie_port *port)
147{
148	return port->io_target != -1 && port->io_attr != -1;
149}
150
151static bool mvebu_pcie_link_up(struct mvebu_pcie_port *port)
152{
153	return !(mvebu_readl(port, PCIE_STAT_OFF) & PCIE_STAT_LINK_DOWN);
154}
155
156static void mvebu_pcie_set_local_bus_nr(struct mvebu_pcie_port *port, int nr)
157{
158	u32 stat;
159
160	stat = mvebu_readl(port, PCIE_STAT_OFF);
161	stat &= ~PCIE_STAT_BUS;
162	stat |= nr << 8;
163	mvebu_writel(port, stat, PCIE_STAT_OFF);
164}
165
166static void mvebu_pcie_set_local_dev_nr(struct mvebu_pcie_port *port, int nr)
167{
168	u32 stat;
169
170	stat = mvebu_readl(port, PCIE_STAT_OFF);
171	stat &= ~PCIE_STAT_DEV;
172	stat |= nr << 16;
173	mvebu_writel(port, stat, PCIE_STAT_OFF);
174}
175
176/*
177 * Setup PCIE BARs and Address Decode Wins:
178 * BAR[0,2] -> disabled, BAR[1] -> covers all DRAM banks
179 * WIN[0-3] -> DRAM bank[0-3]
180 */
181static void mvebu_pcie_setup_wins(struct mvebu_pcie_port *port)
182{
183	const struct mbus_dram_target_info *dram;
184	u32 size;
185	int i;
186
187	dram = mv_mbus_dram_info();
188
189	/* First, disable and clear BARs and windows. */
190	for (i = 1; i < 3; i++) {
191		mvebu_writel(port, 0, PCIE_BAR_CTRL_OFF(i));
192		mvebu_writel(port, 0, PCIE_BAR_LO_OFF(i));
193		mvebu_writel(port, 0, PCIE_BAR_HI_OFF(i));
194	}
195
196	for (i = 0; i < 5; i++) {
197		mvebu_writel(port, 0, PCIE_WIN04_CTRL_OFF(i));
198		mvebu_writel(port, 0, PCIE_WIN04_BASE_OFF(i));
199		mvebu_writel(port, 0, PCIE_WIN04_REMAP_OFF(i));
200	}
201
202	mvebu_writel(port, 0, PCIE_WIN5_CTRL_OFF);
203	mvebu_writel(port, 0, PCIE_WIN5_BASE_OFF);
204	mvebu_writel(port, 0, PCIE_WIN5_REMAP_OFF);
205
206	/* Setup windows for DDR banks.  Count total DDR size on the fly. */
207	size = 0;
208	for (i = 0; i < dram->num_cs; i++) {
209		const struct mbus_dram_window *cs = dram->cs + i;
210
211		mvebu_writel(port, cs->base & 0xffff0000,
212			     PCIE_WIN04_BASE_OFF(i));
213		mvebu_writel(port, 0, PCIE_WIN04_REMAP_OFF(i));
214		mvebu_writel(port,
215			     ((cs->size - 1) & 0xffff0000) |
216			     (cs->mbus_attr << 8) |
217			     (dram->mbus_dram_target_id << 4) | 1,
218			     PCIE_WIN04_CTRL_OFF(i));
219
220		size += cs->size;
221	}
222
223	/* Round up 'size' to the nearest power of two. */
224	if ((size & (size - 1)) != 0)
225		size = 1 << fls(size);
226
227	/* Setup BAR[1] to all DRAM banks. */
228	mvebu_writel(port, dram->cs[0].base, PCIE_BAR_LO_OFF(1));
229	mvebu_writel(port, 0, PCIE_BAR_HI_OFF(1));
230	mvebu_writel(port, ((size - 1) & 0xffff0000) | 1,
231		     PCIE_BAR_CTRL_OFF(1));
232}
233
234static void mvebu_pcie_setup_hw(struct mvebu_pcie_port *port)
235{
236	u32 cmd, mask;
237
238	/* Point PCIe unit MBUS decode windows to DRAM space. */
239	mvebu_pcie_setup_wins(port);
240
241	/* Master + slave enable. */
242	cmd = mvebu_readl(port, PCIE_CMD_OFF);
243	cmd |= PCI_COMMAND_IO;
244	cmd |= PCI_COMMAND_MEMORY;
245	cmd |= PCI_COMMAND_MASTER;
246	mvebu_writel(port, cmd, PCIE_CMD_OFF);
247
248	/* Enable interrupt lines A-D. */
249	mask = mvebu_readl(port, PCIE_MASK_OFF);
250	mask |= PCIE_MASK_ENABLE_INTS;
251	mvebu_writel(port, mask, PCIE_MASK_OFF);
252}
253
254static int mvebu_pcie_hw_rd_conf(struct mvebu_pcie_port *port,
255				 struct pci_bus *bus,
256				 u32 devfn, int where, int size, u32 *val)
257{
258	mvebu_writel(port, PCIE_CONF_ADDR(bus->number, devfn, where),
259		     PCIE_CONF_ADDR_OFF);
260
261	*val = mvebu_readl(port, PCIE_CONF_DATA_OFF);
262
263	if (size == 1)
264		*val = (*val >> (8 * (where & 3))) & 0xff;
265	else if (size == 2)
266		*val = (*val >> (8 * (where & 3))) & 0xffff;
267
268	return PCIBIOS_SUCCESSFUL;
269}
270
271static int mvebu_pcie_hw_wr_conf(struct mvebu_pcie_port *port,
272				 struct pci_bus *bus,
273				 u32 devfn, int where, int size, u32 val)
274{
275	u32 _val, shift = 8 * (where & 3);
276
277	mvebu_writel(port, PCIE_CONF_ADDR(bus->number, devfn, where),
278		     PCIE_CONF_ADDR_OFF);
279	_val = mvebu_readl(port, PCIE_CONF_DATA_OFF);
280
281	if (size == 4)
282		_val = val;
283	else if (size == 2)
284		_val = (_val & ~(0xffff << shift)) | ((val & 0xffff) << shift);
285	else if (size == 1)
286		_val = (_val & ~(0xff << shift)) | ((val & 0xff) << shift);
287	else
288		return PCIBIOS_BAD_REGISTER_NUMBER;
289
290	mvebu_writel(port, _val, PCIE_CONF_DATA_OFF);
291
292	return PCIBIOS_SUCCESSFUL;
293}
294
295/*
296 * Remove windows, starting from the largest ones to the smallest
297 * ones.
298 */
299static void mvebu_pcie_del_windows(struct mvebu_pcie_port *port,
300				   phys_addr_t base, size_t size)
301{
302	while (size) {
303		size_t sz = 1 << (fls(size) - 1);
304
305		mvebu_mbus_del_window(base, sz);
306		base += sz;
307		size -= sz;
308	}
309}
310
311/*
312 * MBus windows can only have a power of two size, but PCI BARs do not
313 * have this constraint. Therefore, we have to split the PCI BAR into
314 * areas each having a power of two size. We start from the largest
315 * one (i.e highest order bit set in the size).
316 */
317static void mvebu_pcie_add_windows(struct mvebu_pcie_port *port,
318				   unsigned int target, unsigned int attribute,
319				   phys_addr_t base, size_t size,
320				   phys_addr_t remap)
321{
322	size_t size_mapped = 0;
323
324	while (size) {
325		size_t sz = 1 << (fls(size) - 1);
326		int ret;
327
328		ret = mvebu_mbus_add_window_remap_by_id(target, attribute, base,
329							sz, remap);
330		if (ret) {
331			phys_addr_t end = base + sz - 1;
332
333			dev_err(&port->pcie->pdev->dev,
334				"Could not create MBus window at [mem %pa-%pa]: %d\n",
335				&base, &end, ret);
336			mvebu_pcie_del_windows(port, base - size_mapped,
337					       size_mapped);
338			return;
339		}
340
341		size -= sz;
342		size_mapped += sz;
343		base += sz;
344		if (remap != MVEBU_MBUS_NO_REMAP)
345			remap += sz;
346	}
347}
348
349static void mvebu_pcie_handle_iobase_change(struct mvebu_pcie_port *port)
350{
351	phys_addr_t iobase;
352
353	/* Are the new iobase/iolimit values invalid? */
354	if (port->bridge.iolimit < port->bridge.iobase ||
355	    port->bridge.iolimitupper < port->bridge.iobaseupper ||
356	    !(port->bridge.command & PCI_COMMAND_IO)) {
357
358		/* If a window was configured, remove it */
359		if (port->iowin_base) {
360			mvebu_pcie_del_windows(port, port->iowin_base,
361					       port->iowin_size);
362			port->iowin_base = 0;
363			port->iowin_size = 0;
364		}
365
366		return;
367	}
368
369	if (!mvebu_has_ioport(port)) {
370		dev_WARN(&port->pcie->pdev->dev,
371			 "Attempt to set IO when IO is disabled\n");
372		return;
373	}
374
375	/*
376	 * We read the PCI-to-PCI bridge emulated registers, and
377	 * calculate the base address and size of the address decoding
378	 * window to setup, according to the PCI-to-PCI bridge
379	 * specifications. iobase is the bus address, port->iowin_base
380	 * is the CPU address.
381	 */
382	iobase = ((port->bridge.iobase & 0xF0) << 8) |
383		(port->bridge.iobaseupper << 16);
384	port->iowin_base = port->pcie->io.start + iobase;
385	port->iowin_size = ((0xFFF | ((port->bridge.iolimit & 0xF0) << 8) |
386			    (port->bridge.iolimitupper << 16)) -
387			    iobase) + 1;
388
389	mvebu_pcie_add_windows(port, port->io_target, port->io_attr,
390			       port->iowin_base, port->iowin_size,
391			       iobase);
392}
393
394static void mvebu_pcie_handle_membase_change(struct mvebu_pcie_port *port)
395{
396	/* Are the new membase/memlimit values invalid? */
397	if (port->bridge.memlimit < port->bridge.membase ||
398	    !(port->bridge.command & PCI_COMMAND_MEMORY)) {
399
400		/* If a window was configured, remove it */
401		if (port->memwin_base) {
402			mvebu_pcie_del_windows(port, port->memwin_base,
403					       port->memwin_size);
404			port->memwin_base = 0;
405			port->memwin_size = 0;
406		}
407
408		return;
409	}
410
411	/*
412	 * We read the PCI-to-PCI bridge emulated registers, and
413	 * calculate the base address and size of the address decoding
414	 * window to setup, according to the PCI-to-PCI bridge
415	 * specifications.
416	 */
417	port->memwin_base  = ((port->bridge.membase & 0xFFF0) << 16);
418	port->memwin_size  =
419		(((port->bridge.memlimit & 0xFFF0) << 16) | 0xFFFFF) -
420		port->memwin_base + 1;
421
422	mvebu_pcie_add_windows(port, port->mem_target, port->mem_attr,
423			       port->memwin_base, port->memwin_size,
424			       MVEBU_MBUS_NO_REMAP);
425}
426
427/*
428 * Initialize the configuration space of the PCI-to-PCI bridge
429 * associated with the given PCIe interface.
430 */
431static void mvebu_sw_pci_bridge_init(struct mvebu_pcie_port *port)
432{
433	struct mvebu_sw_pci_bridge *bridge = &port->bridge;
434
435	memset(bridge, 0, sizeof(struct mvebu_sw_pci_bridge));
436
437	bridge->class = PCI_CLASS_BRIDGE_PCI;
438	bridge->vendor = PCI_VENDOR_ID_MARVELL;
439	bridge->device = mvebu_readl(port, PCIE_DEV_ID_OFF) >> 16;
440	bridge->revision = mvebu_readl(port, PCIE_DEV_REV_OFF) & 0xff;
441	bridge->header_type = PCI_HEADER_TYPE_BRIDGE;
442	bridge->cache_line_size = 0x10;
443
444	/* We support 32 bits I/O addressing */
445	bridge->iobase = PCI_IO_RANGE_TYPE_32;
446	bridge->iolimit = PCI_IO_RANGE_TYPE_32;
447}
448
449/*
450 * Read the configuration space of the PCI-to-PCI bridge associated to
451 * the given PCIe interface.
452 */
453static int mvebu_sw_pci_bridge_read(struct mvebu_pcie_port *port,
454				  unsigned int where, int size, u32 *value)
455{
456	struct mvebu_sw_pci_bridge *bridge = &port->bridge;
457
458	switch (where & ~3) {
459	case PCI_VENDOR_ID:
460		*value = bridge->device << 16 | bridge->vendor;
461		break;
462
463	case PCI_COMMAND:
464		*value = bridge->command;
465		break;
466
467	case PCI_CLASS_REVISION:
468		*value = bridge->class << 16 | bridge->interface << 8 |
469			 bridge->revision;
470		break;
471
472	case PCI_CACHE_LINE_SIZE:
473		*value = bridge->bist << 24 | bridge->header_type << 16 |
474			 bridge->latency_timer << 8 | bridge->cache_line_size;
475		break;
476
477	case PCI_BASE_ADDRESS_0 ... PCI_BASE_ADDRESS_1:
478		*value = bridge->bar[((where & ~3) - PCI_BASE_ADDRESS_0) / 4];
479		break;
480
481	case PCI_PRIMARY_BUS:
482		*value = (bridge->secondary_latency_timer << 24 |
483			  bridge->subordinate_bus         << 16 |
484			  bridge->secondary_bus           <<  8 |
485			  bridge->primary_bus);
486		break;
487
488	case PCI_IO_BASE:
489		if (!mvebu_has_ioport(port))
490			*value = bridge->secondary_status << 16;
491		else
492			*value = (bridge->secondary_status << 16 |
493				  bridge->iolimit          <<  8 |
494				  bridge->iobase);
495		break;
496
497	case PCI_MEMORY_BASE:
498		*value = (bridge->memlimit << 16 | bridge->membase);
499		break;
500
501	case PCI_PREF_MEMORY_BASE:
502		*value = 0;
503		break;
504
505	case PCI_IO_BASE_UPPER16:
506		*value = (bridge->iolimitupper << 16 | bridge->iobaseupper);
507		break;
508
509	case PCI_ROM_ADDRESS1:
510		*value = 0;
511		break;
512
513	case PCI_INTERRUPT_LINE:
514		/* LINE PIN MIN_GNT MAX_LAT */
515		*value = 0;
516		break;
517
518	default:
519		*value = 0xffffffff;
520		return PCIBIOS_BAD_REGISTER_NUMBER;
521	}
522
523	if (size == 2)
524		*value = (*value >> (8 * (where & 3))) & 0xffff;
525	else if (size == 1)
526		*value = (*value >> (8 * (where & 3))) & 0xff;
527
528	return PCIBIOS_SUCCESSFUL;
529}
530
531/* Write to the PCI-to-PCI bridge configuration space */
532static int mvebu_sw_pci_bridge_write(struct mvebu_pcie_port *port,
533				     unsigned int where, int size, u32 value)
534{
535	struct mvebu_sw_pci_bridge *bridge = &port->bridge;
536	u32 mask, reg;
537	int err;
538
539	if (size == 4)
540		mask = 0x0;
541	else if (size == 2)
542		mask = ~(0xffff << ((where & 3) * 8));
543	else if (size == 1)
544		mask = ~(0xff << ((where & 3) * 8));
545	else
546		return PCIBIOS_BAD_REGISTER_NUMBER;
547
548	err = mvebu_sw_pci_bridge_read(port, where & ~3, 4, &reg);
549	if (err)
550		return err;
551
552	value = (reg & mask) | value << ((where & 3) * 8);
553
554	switch (where & ~3) {
555	case PCI_COMMAND:
556	{
557		u32 old = bridge->command;
558
559		if (!mvebu_has_ioport(port))
560			value &= ~PCI_COMMAND_IO;
561
562		bridge->command = value & 0xffff;
563		if ((old ^ bridge->command) & PCI_COMMAND_IO)
564			mvebu_pcie_handle_iobase_change(port);
565		if ((old ^ bridge->command) & PCI_COMMAND_MEMORY)
566			mvebu_pcie_handle_membase_change(port);
567		break;
568	}
569
570	case PCI_BASE_ADDRESS_0 ... PCI_BASE_ADDRESS_1:
571		bridge->bar[((where & ~3) - PCI_BASE_ADDRESS_0) / 4] = value;
572		break;
573
574	case PCI_IO_BASE:
575		/*
576		 * We also keep bit 1 set, it is a read-only bit that
577		 * indicates we support 32 bits addressing for the
578		 * I/O
579		 */
580		bridge->iobase = (value & 0xff) | PCI_IO_RANGE_TYPE_32;
581		bridge->iolimit = ((value >> 8) & 0xff) | PCI_IO_RANGE_TYPE_32;
582		mvebu_pcie_handle_iobase_change(port);
583		break;
584
585	case PCI_MEMORY_BASE:
586		bridge->membase = value & 0xffff;
587		bridge->memlimit = value >> 16;
588		mvebu_pcie_handle_membase_change(port);
589		break;
590
591	case PCI_IO_BASE_UPPER16:
592		bridge->iobaseupper = value & 0xffff;
593		bridge->iolimitupper = value >> 16;
594		mvebu_pcie_handle_iobase_change(port);
595		break;
596
597	case PCI_PRIMARY_BUS:
598		bridge->primary_bus             = value & 0xff;
599		bridge->secondary_bus           = (value >> 8) & 0xff;
600		bridge->subordinate_bus         = (value >> 16) & 0xff;
601		bridge->secondary_latency_timer = (value >> 24) & 0xff;
602		mvebu_pcie_set_local_bus_nr(port, bridge->secondary_bus);
603		break;
604
605	default:
606		break;
607	}
608
609	return PCIBIOS_SUCCESSFUL;
610}
611
612static inline struct mvebu_pcie *sys_to_pcie(struct pci_sys_data *sys)
613{
614	return sys->private_data;
615}
616
617static struct mvebu_pcie_port *mvebu_pcie_find_port(struct mvebu_pcie *pcie,
618						    struct pci_bus *bus,
619						    int devfn)
620{
621	int i;
622
623	for (i = 0; i < pcie->nports; i++) {
624		struct mvebu_pcie_port *port = &pcie->ports[i];
625		if (bus->number == 0 && port->devfn == devfn)
626			return port;
627		if (bus->number != 0 &&
628		    bus->number >= port->bridge.secondary_bus &&
629		    bus->number <= port->bridge.subordinate_bus)
630			return port;
631	}
632
633	return NULL;
634}
635
636/* PCI configuration space write function */
637static int mvebu_pcie_wr_conf(struct pci_bus *bus, u32 devfn,
638			      int where, int size, u32 val)
639{
640	struct mvebu_pcie *pcie = sys_to_pcie(bus->sysdata);
641	struct mvebu_pcie_port *port;
642	int ret;
643
644	port = mvebu_pcie_find_port(pcie, bus, devfn);
645	if (!port)
646		return PCIBIOS_DEVICE_NOT_FOUND;
647
648	/* Access the emulated PCI-to-PCI bridge */
649	if (bus->number == 0)
650		return mvebu_sw_pci_bridge_write(port, where, size, val);
651
652	if (!mvebu_pcie_link_up(port))
653		return PCIBIOS_DEVICE_NOT_FOUND;
654
655	/*
656	 * On the secondary bus, we don't want to expose any other
657	 * device than the device physically connected in the PCIe
658	 * slot, visible in slot 0. In slot 1, there's a special
659	 * Marvell device that only makes sense when the Armada is
660	 * used as a PCIe endpoint.
661	 */
662	if (bus->number == port->bridge.secondary_bus &&
663	    PCI_SLOT(devfn) != 0)
664		return PCIBIOS_DEVICE_NOT_FOUND;
665
666	/* Access the real PCIe interface */
667	ret = mvebu_pcie_hw_wr_conf(port, bus, devfn,
668				    where, size, val);
669
670	return ret;
671}
672
673/* PCI configuration space read function */
674static int mvebu_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
675			      int size, u32 *val)
676{
677	struct mvebu_pcie *pcie = sys_to_pcie(bus->sysdata);
678	struct mvebu_pcie_port *port;
679	int ret;
680
681	port = mvebu_pcie_find_port(pcie, bus, devfn);
682	if (!port) {
683		*val = 0xffffffff;
684		return PCIBIOS_DEVICE_NOT_FOUND;
685	}
686
687	/* Access the emulated PCI-to-PCI bridge */
688	if (bus->number == 0)
689		return mvebu_sw_pci_bridge_read(port, where, size, val);
690
691	if (!mvebu_pcie_link_up(port)) {
692		*val = 0xffffffff;
693		return PCIBIOS_DEVICE_NOT_FOUND;
694	}
695
696	/*
697	 * On the secondary bus, we don't want to expose any other
698	 * device than the device physically connected in the PCIe
699	 * slot, visible in slot 0. In slot 1, there's a special
700	 * Marvell device that only makes sense when the Armada is
701	 * used as a PCIe endpoint.
702	 */
703	if (bus->number == port->bridge.secondary_bus &&
704	    PCI_SLOT(devfn) != 0) {
705		*val = 0xffffffff;
706		return PCIBIOS_DEVICE_NOT_FOUND;
707	}
708
709	/* Access the real PCIe interface */
710	ret = mvebu_pcie_hw_rd_conf(port, bus, devfn,
711				    where, size, val);
712
713	return ret;
714}
715
716static struct pci_ops mvebu_pcie_ops = {
717	.read = mvebu_pcie_rd_conf,
718	.write = mvebu_pcie_wr_conf,
719};
720
721static int mvebu_pcie_setup(int nr, struct pci_sys_data *sys)
722{
723	struct mvebu_pcie *pcie = sys_to_pcie(sys);
724	int i;
725	int domain = 0;
726
727#ifdef CONFIG_PCI_DOMAINS
728	domain = sys->domain;
729#endif
730
731	snprintf(pcie->mem_name, sizeof(pcie->mem_name), "PCI MEM %04x",
732		 domain);
733	pcie->mem.name = pcie->mem_name;
734
735	snprintf(pcie->io_name, sizeof(pcie->io_name), "PCI I/O %04x", domain);
736	pcie->realio.name = pcie->io_name;
737
738	if (request_resource(&iomem_resource, &pcie->mem))
739		return 0;
740
741	if (resource_size(&pcie->realio) != 0) {
742		if (request_resource(&ioport_resource, &pcie->realio)) {
743			release_resource(&pcie->mem);
744			return 0;
745		}
746		pci_add_resource_offset(&sys->resources, &pcie->realio,
747					sys->io_offset);
748	}
749	pci_add_resource_offset(&sys->resources, &pcie->mem, sys->mem_offset);
750	pci_add_resource(&sys->resources, &pcie->busn);
751
752	for (i = 0; i < pcie->nports; i++) {
753		struct mvebu_pcie_port *port = &pcie->ports[i];
754		if (!port->base)
755			continue;
756		mvebu_pcie_setup_hw(port);
757	}
758
759	return 1;
760}
761
762static struct pci_bus *mvebu_pcie_scan_bus(int nr, struct pci_sys_data *sys)
763{
764	struct mvebu_pcie *pcie = sys_to_pcie(sys);
765	struct pci_bus *bus;
766
767	bus = pci_create_root_bus(&pcie->pdev->dev, sys->busnr,
768				  &mvebu_pcie_ops, sys, &sys->resources);
769	if (!bus)
770		return NULL;
771
772	pci_scan_child_bus(bus);
773
774	return bus;
775}
776
777static void mvebu_pcie_add_bus(struct pci_bus *bus)
778{
779	struct mvebu_pcie *pcie = sys_to_pcie(bus->sysdata);
780	bus->msi = pcie->msi;
781}
782
783static resource_size_t mvebu_pcie_align_resource(struct pci_dev *dev,
784						 const struct resource *res,
785						 resource_size_t start,
786						 resource_size_t size,
787						 resource_size_t align)
788{
789	if (dev->bus->number != 0)
790		return start;
791
792	/*
793	 * On the PCI-to-PCI bridge side, the I/O windows must have at
794	 * least a 64 KB size and the memory windows must have at
795	 * least a 1 MB size. Moreover, MBus windows need to have a
796	 * base address aligned on their size, and their size must be
797	 * a power of two. This means that if the BAR doesn't have a
798	 * power of two size, several MBus windows will actually be
799	 * created. We need to ensure that the biggest MBus window
800	 * (which will be the first one) is aligned on its size, which
801	 * explains the rounddown_pow_of_two() being done here.
802	 */
803	if (res->flags & IORESOURCE_IO)
804		return round_up(start, max_t(resource_size_t, SZ_64K,
805					     rounddown_pow_of_two(size)));
806	else if (res->flags & IORESOURCE_MEM)
807		return round_up(start, max_t(resource_size_t, SZ_1M,
808					     rounddown_pow_of_two(size)));
809	else
810		return start;
811}
812
813static void mvebu_pcie_enable(struct mvebu_pcie *pcie)
814{
815	struct hw_pci hw;
816
817	memset(&hw, 0, sizeof(hw));
818
819	hw.nr_controllers = 1;
820	hw.private_data   = (void **)&pcie;
821	hw.setup          = mvebu_pcie_setup;
822	hw.scan           = mvebu_pcie_scan_bus;
823	hw.map_irq        = of_irq_parse_and_map_pci;
824	hw.ops            = &mvebu_pcie_ops;
825	hw.align_resource = mvebu_pcie_align_resource;
826	hw.add_bus        = mvebu_pcie_add_bus;
827
828	pci_common_init(&hw);
829}
830
831/*
832 * Looks up the list of register addresses encoded into the reg =
833 * <...> property for one that matches the given port/lane. Once
834 * found, maps it.
835 */
836static void __iomem *mvebu_pcie_map_registers(struct platform_device *pdev,
837					      struct device_node *np,
838					      struct mvebu_pcie_port *port)
839{
840	struct resource regs;
841	int ret = 0;
842
843	ret = of_address_to_resource(np, 0, &regs);
844	if (ret)
845		return ERR_PTR(ret);
846
847	return devm_ioremap_resource(&pdev->dev, &regs);
848}
849
850#define DT_FLAGS_TO_TYPE(flags)       (((flags) >> 24) & 0x03)
851#define    DT_TYPE_IO                 0x1
852#define    DT_TYPE_MEM32              0x2
853#define DT_CPUADDR_TO_TARGET(cpuaddr) (((cpuaddr) >> 56) & 0xFF)
854#define DT_CPUADDR_TO_ATTR(cpuaddr)   (((cpuaddr) >> 48) & 0xFF)
855
856static int mvebu_get_tgt_attr(struct device_node *np, int devfn,
857			      unsigned long type,
858			      unsigned int *tgt,
859			      unsigned int *attr)
860{
861	const int na = 3, ns = 2;
862	const __be32 *range;
863	int rlen, nranges, rangesz, pna, i;
864
865	*tgt = -1;
866	*attr = -1;
867
868	range = of_get_property(np, "ranges", &rlen);
869	if (!range)
870		return -EINVAL;
871
872	pna = of_n_addr_cells(np);
873	rangesz = pna + na + ns;
874	nranges = rlen / sizeof(__be32) / rangesz;
875
876	for (i = 0; i < nranges; i++, range += rangesz) {
877		u32 flags = of_read_number(range, 1);
878		u32 slot = of_read_number(range + 1, 1);
879		u64 cpuaddr = of_read_number(range + na, pna);
880		unsigned long rtype;
881
882		if (DT_FLAGS_TO_TYPE(flags) == DT_TYPE_IO)
883			rtype = IORESOURCE_IO;
884		else if (DT_FLAGS_TO_TYPE(flags) == DT_TYPE_MEM32)
885			rtype = IORESOURCE_MEM;
886		else
887			continue;
888
889		if (slot == PCI_SLOT(devfn) && type == rtype) {
890			*tgt = DT_CPUADDR_TO_TARGET(cpuaddr);
891			*attr = DT_CPUADDR_TO_ATTR(cpuaddr);
892			return 0;
893		}
894	}
895
896	return -ENOENT;
897}
898
899static void mvebu_pcie_msi_enable(struct mvebu_pcie *pcie)
900{
901	struct device_node *msi_node;
902
903	msi_node = of_parse_phandle(pcie->pdev->dev.of_node,
904				    "msi-parent", 0);
905	if (!msi_node)
906		return;
907
908	pcie->msi = of_pci_find_msi_chip_by_node(msi_node);
909
910	if (pcie->msi)
911		pcie->msi->dev = &pcie->pdev->dev;
912}
913
914static int mvebu_pcie_probe(struct platform_device *pdev)
915{
916	struct mvebu_pcie *pcie;
917	struct device_node *np = pdev->dev.of_node;
918	struct device_node *child;
919	int i, ret;
920
921	pcie = devm_kzalloc(&pdev->dev, sizeof(struct mvebu_pcie),
922			    GFP_KERNEL);
923	if (!pcie)
924		return -ENOMEM;
925
926	pcie->pdev = pdev;
927	platform_set_drvdata(pdev, pcie);
928
929	/* Get the PCIe memory and I/O aperture */
930	mvebu_mbus_get_pcie_mem_aperture(&pcie->mem);
931	if (resource_size(&pcie->mem) == 0) {
932		dev_err(&pdev->dev, "invalid memory aperture size\n");
933		return -EINVAL;
934	}
935
936	mvebu_mbus_get_pcie_io_aperture(&pcie->io);
937
938	if (resource_size(&pcie->io) != 0) {
939		pcie->realio.flags = pcie->io.flags;
940		pcie->realio.start = PCIBIOS_MIN_IO;
941		pcie->realio.end = min_t(resource_size_t,
942					 IO_SPACE_LIMIT,
943					 resource_size(&pcie->io));
944	} else
945		pcie->realio = pcie->io;
946
947	/* Get the bus range */
948	ret = of_pci_parse_bus_range(np, &pcie->busn);
949	if (ret) {
950		dev_err(&pdev->dev, "failed to parse bus-range property: %d\n",
951			ret);
952		return ret;
953	}
954
955	i = 0;
956	for_each_child_of_node(pdev->dev.of_node, child) {
957		if (!of_device_is_available(child))
958			continue;
959		i++;
960	}
961
962	pcie->ports = devm_kzalloc(&pdev->dev, i *
963				   sizeof(struct mvebu_pcie_port),
964				   GFP_KERNEL);
965	if (!pcie->ports)
966		return -ENOMEM;
967
968	i = 0;
969	for_each_child_of_node(pdev->dev.of_node, child) {
970		struct mvebu_pcie_port *port = &pcie->ports[i];
971		enum of_gpio_flags flags;
972
973		if (!of_device_is_available(child))
974			continue;
975
976		port->pcie = pcie;
977
978		if (of_property_read_u32(child, "marvell,pcie-port",
979					 &port->port)) {
980			dev_warn(&pdev->dev,
981				 "ignoring PCIe DT node, missing pcie-port property\n");
982			continue;
983		}
984
985		if (of_property_read_u32(child, "marvell,pcie-lane",
986					 &port->lane))
987			port->lane = 0;
988
989		port->name = kasprintf(GFP_KERNEL, "pcie%d.%d",
990				       port->port, port->lane);
991
992		port->devfn = of_pci_get_devfn(child);
993		if (port->devfn < 0)
994			continue;
995
996		ret = mvebu_get_tgt_attr(np, port->devfn, IORESOURCE_MEM,
997					 &port->mem_target, &port->mem_attr);
998		if (ret < 0) {
999			dev_err(&pdev->dev, "PCIe%d.%d: cannot get tgt/attr for mem window\n",
1000				port->port, port->lane);
1001			continue;
1002		}
1003
1004		if (resource_size(&pcie->io) != 0)
1005			mvebu_get_tgt_attr(np, port->devfn, IORESOURCE_IO,
1006					   &port->io_target, &port->io_attr);
1007		else {
1008			port->io_target = -1;
1009			port->io_attr = -1;
1010		}
1011
1012		port->reset_gpio = of_get_named_gpio_flags(child,
1013						   "reset-gpios", 0, &flags);
1014		if (gpio_is_valid(port->reset_gpio)) {
1015			u32 reset_udelay = 20000;
1016
1017			port->reset_active_low = flags & OF_GPIO_ACTIVE_LOW;
1018			port->reset_name = kasprintf(GFP_KERNEL,
1019				     "pcie%d.%d-reset", port->port, port->lane);
1020			of_property_read_u32(child, "reset-delay-us",
1021					     &reset_udelay);
1022
1023			ret = devm_gpio_request_one(&pdev->dev,
1024			    port->reset_gpio, GPIOF_DIR_OUT, port->reset_name);
1025			if (ret) {
1026				if (ret == -EPROBE_DEFER)
1027					return ret;
1028				continue;
1029			}
1030
1031			gpio_set_value(port->reset_gpio,
1032				       (port->reset_active_low) ? 1 : 0);
1033			msleep(reset_udelay/1000);
1034		}
1035
1036		port->clk = of_clk_get_by_name(child, NULL);
1037		if (IS_ERR(port->clk)) {
1038			dev_err(&pdev->dev, "PCIe%d.%d: cannot get clock\n",
1039			       port->port, port->lane);
1040			continue;
1041		}
1042
1043		ret = clk_prepare_enable(port->clk);
1044		if (ret)
1045			continue;
1046
1047		port->base = mvebu_pcie_map_registers(pdev, child, port);
1048		if (IS_ERR(port->base)) {
1049			dev_err(&pdev->dev, "PCIe%d.%d: cannot map registers\n",
1050				port->port, port->lane);
1051			port->base = NULL;
1052			clk_disable_unprepare(port->clk);
1053			continue;
1054		}
1055
1056		mvebu_pcie_set_local_dev_nr(port, 1);
1057
1058		port->dn = child;
1059		mvebu_sw_pci_bridge_init(port);
1060		i++;
1061	}
1062
1063	pcie->nports = i;
1064
1065	for (i = 0; i < (IO_SPACE_LIMIT - SZ_64K); i += SZ_64K)
1066		pci_ioremap_io(i, pcie->io.start + i);
1067
1068	mvebu_pcie_msi_enable(pcie);
1069	mvebu_pcie_enable(pcie);
1070
1071	return 0;
1072}
1073
1074static const struct of_device_id mvebu_pcie_of_match_table[] = {
1075	{ .compatible = "marvell,armada-xp-pcie", },
1076	{ .compatible = "marvell,armada-370-pcie", },
1077	{ .compatible = "marvell,dove-pcie", },
1078	{ .compatible = "marvell,kirkwood-pcie", },
1079	{},
1080};
1081MODULE_DEVICE_TABLE(of, mvebu_pcie_of_match_table);
1082
1083static struct platform_driver mvebu_pcie_driver = {
1084	.driver = {
1085		.owner = THIS_MODULE,
1086		.name = "mvebu-pcie",
1087		.of_match_table = mvebu_pcie_of_match_table,
1088		/* driver unloading/unbinding currently not supported */
1089		.suppress_bind_attrs = true,
1090	},
1091	.probe = mvebu_pcie_probe,
1092};
1093module_platform_driver(mvebu_pcie_driver);
1094
1095MODULE_AUTHOR("Thomas Petazzoni <thomas.petazzoni@free-electrons.com>");
1096MODULE_DESCRIPTION("Marvell EBU PCIe driver");
1097MODULE_LICENSE("GPL v2");
1098