xref: /linux/drivers/pci/controller/pci-mvebu.c (revision 0ea5c948cb64bab5bc7a5516774eb8536f05aa0d)
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/module.h>
10 #include <linux/pci.h>
11 #include <linux/bitfield.h>
12 #include <linux/clk.h>
13 #include <linux/delay.h>
14 #include <linux/gpio/consumer.h>
15 #include <linux/init.h>
16 #include <linux/irqchip/chained_irq.h>
17 #include <linux/irqdomain.h>
18 #include <linux/mbus.h>
19 #include <linux/slab.h>
20 #include <linux/platform_device.h>
21 #include <linux/of_address.h>
22 #include <linux/of_irq.h>
23 #include <linux/of_pci.h>
24 #include <linux/of_platform.h>
25 
26 #include "../pci.h"
27 #include "../pci-bridge-emul.h"
28 
29 /*
30  * PCIe unit register offsets.
31  */
32 #define PCIE_DEV_ID_OFF		0x0000
33 #define PCIE_CMD_OFF		0x0004
34 #define PCIE_DEV_REV_OFF	0x0008
35 #define PCIE_BAR_LO_OFF(n)	(0x0010 + ((n) << 3))
36 #define PCIE_BAR_HI_OFF(n)	(0x0014 + ((n) << 3))
37 #define PCIE_SSDEV_ID_OFF	0x002c
38 #define PCIE_CAP_PCIEXP		0x0060
39 #define PCIE_CAP_PCIERR_OFF	0x0100
40 #define PCIE_BAR_CTRL_OFF(n)	(0x1804 + (((n) - 1) * 4))
41 #define PCIE_WIN04_CTRL_OFF(n)	(0x1820 + ((n) << 4))
42 #define PCIE_WIN04_BASE_OFF(n)	(0x1824 + ((n) << 4))
43 #define PCIE_WIN04_REMAP_OFF(n)	(0x182c + ((n) << 4))
44 #define PCIE_WIN5_CTRL_OFF	0x1880
45 #define PCIE_WIN5_BASE_OFF	0x1884
46 #define PCIE_WIN5_REMAP_OFF	0x188c
47 #define PCIE_CONF_ADDR_OFF	0x18f8
48 #define  PCIE_CONF_ADDR_EN		0x80000000
49 #define  PCIE_CONF_REG(r)		((((r) & 0xf00) << 16) | ((r) & 0xfc))
50 #define  PCIE_CONF_BUS(b)		(((b) & 0xff) << 16)
51 #define  PCIE_CONF_DEV(d)		(((d) & 0x1f) << 11)
52 #define  PCIE_CONF_FUNC(f)		(((f) & 0x7) << 8)
53 #define  PCIE_CONF_ADDR(bus, devfn, where) \
54 	(PCIE_CONF_BUS(bus) | PCIE_CONF_DEV(PCI_SLOT(devfn))    | \
55 	 PCIE_CONF_FUNC(PCI_FUNC(devfn)) | PCIE_CONF_REG(where) | \
56 	 PCIE_CONF_ADDR_EN)
57 #define PCIE_CONF_DATA_OFF	0x18fc
58 #define PCIE_INT_CAUSE_OFF	0x1900
59 #define PCIE_INT_UNMASK_OFF	0x1910
60 #define  PCIE_INT_INTX(i)		BIT(24+i)
61 #define  PCIE_INT_PM_PME		BIT(28)
62 #define  PCIE_INT_ALL_MASK		GENMASK(31, 0)
63 #define PCIE_CTRL_OFF		0x1a00
64 #define  PCIE_CTRL_X1_MODE		0x0001
65 #define  PCIE_CTRL_RC_MODE		BIT(1)
66 #define  PCIE_CTRL_MASTER_HOT_RESET	BIT(24)
67 #define PCIE_STAT_OFF		0x1a04
68 #define  PCIE_STAT_BUS                  0xff00
69 #define  PCIE_STAT_DEV                  0x1f0000
70 #define  PCIE_STAT_LINK_DOWN		BIT(0)
71 #define PCIE_SSPL_OFF		0x1a0c
72 #define  PCIE_SSPL_VALUE_SHIFT		0
73 #define  PCIE_SSPL_VALUE_MASK		GENMASK(7, 0)
74 #define  PCIE_SSPL_SCALE_SHIFT		8
75 #define  PCIE_SSPL_SCALE_MASK		GENMASK(9, 8)
76 #define  PCIE_SSPL_ENABLE		BIT(16)
77 #define PCIE_RC_RTSTA		0x1a14
78 #define PCIE_DEBUG_CTRL         0x1a60
79 #define  PCIE_DEBUG_SOFT_RESET		BIT(20)
80 
81 struct mvebu_pcie_port;
82 
83 /* Structure representing all PCIe interfaces */
84 struct mvebu_pcie {
85 	struct platform_device *pdev;
86 	struct mvebu_pcie_port *ports;
87 	struct resource io;
88 	struct resource realio;
89 	struct resource mem;
90 	int nports;
91 };
92 
93 struct mvebu_pcie_window {
94 	phys_addr_t base;
95 	phys_addr_t remap;
96 	size_t size;
97 };
98 
99 /* Structure representing one PCIe interface */
100 struct mvebu_pcie_port {
101 	char *name;
102 	void __iomem *base;
103 	u32 port;
104 	u32 lane;
105 	bool is_x4;
106 	int devfn;
107 	unsigned int mem_target;
108 	unsigned int mem_attr;
109 	unsigned int io_target;
110 	unsigned int io_attr;
111 	struct clk *clk;
112 	struct gpio_desc *reset_gpio;
113 	char *reset_name;
114 	struct pci_bridge_emul bridge;
115 	struct device_node *dn;
116 	struct mvebu_pcie *pcie;
117 	struct mvebu_pcie_window memwin;
118 	struct mvebu_pcie_window iowin;
119 	u32 saved_pcie_stat;
120 	struct resource regs;
121 	u8 slot_power_limit_value;
122 	u8 slot_power_limit_scale;
123 	struct irq_domain *intx_irq_domain;
124 	raw_spinlock_t irq_lock;
125 	int intx_irq;
126 };
127 
mvebu_writel(struct mvebu_pcie_port * port,u32 val,u32 reg)128 static inline void mvebu_writel(struct mvebu_pcie_port *port, u32 val, u32 reg)
129 {
130 	writel(val, port->base + reg);
131 }
132 
mvebu_readl(struct mvebu_pcie_port * port,u32 reg)133 static inline u32 mvebu_readl(struct mvebu_pcie_port *port, u32 reg)
134 {
135 	return readl(port->base + reg);
136 }
137 
mvebu_has_ioport(struct mvebu_pcie_port * port)138 static inline bool mvebu_has_ioport(struct mvebu_pcie_port *port)
139 {
140 	return port->io_target != -1 && port->io_attr != -1;
141 }
142 
mvebu_pcie_link_up(struct mvebu_pcie_port * port)143 static bool mvebu_pcie_link_up(struct mvebu_pcie_port *port)
144 {
145 	return !(mvebu_readl(port, PCIE_STAT_OFF) & PCIE_STAT_LINK_DOWN);
146 }
147 
mvebu_pcie_get_local_bus_nr(struct mvebu_pcie_port * port)148 static u8 mvebu_pcie_get_local_bus_nr(struct mvebu_pcie_port *port)
149 {
150 	return (mvebu_readl(port, PCIE_STAT_OFF) & PCIE_STAT_BUS) >> 8;
151 }
152 
mvebu_pcie_set_local_bus_nr(struct mvebu_pcie_port * port,int nr)153 static void mvebu_pcie_set_local_bus_nr(struct mvebu_pcie_port *port, int nr)
154 {
155 	u32 stat;
156 
157 	stat = mvebu_readl(port, PCIE_STAT_OFF);
158 	stat &= ~PCIE_STAT_BUS;
159 	stat |= nr << 8;
160 	mvebu_writel(port, stat, PCIE_STAT_OFF);
161 }
162 
mvebu_pcie_set_local_dev_nr(struct mvebu_pcie_port * port,int nr)163 static void mvebu_pcie_set_local_dev_nr(struct mvebu_pcie_port *port, int nr)
164 {
165 	u32 stat;
166 
167 	stat = mvebu_readl(port, PCIE_STAT_OFF);
168 	stat &= ~PCIE_STAT_DEV;
169 	stat |= nr << 16;
170 	mvebu_writel(port, stat, PCIE_STAT_OFF);
171 }
172 
mvebu_pcie_disable_wins(struct mvebu_pcie_port * port)173 static void mvebu_pcie_disable_wins(struct mvebu_pcie_port *port)
174 {
175 	int i;
176 
177 	mvebu_writel(port, 0, PCIE_BAR_LO_OFF(0));
178 	mvebu_writel(port, 0, PCIE_BAR_HI_OFF(0));
179 
180 	for (i = 1; i < 3; i++) {
181 		mvebu_writel(port, 0, PCIE_BAR_CTRL_OFF(i));
182 		mvebu_writel(port, 0, PCIE_BAR_LO_OFF(i));
183 		mvebu_writel(port, 0, PCIE_BAR_HI_OFF(i));
184 	}
185 
186 	for (i = 0; i < 5; i++) {
187 		mvebu_writel(port, 0, PCIE_WIN04_CTRL_OFF(i));
188 		mvebu_writel(port, 0, PCIE_WIN04_BASE_OFF(i));
189 		mvebu_writel(port, 0, PCIE_WIN04_REMAP_OFF(i));
190 	}
191 
192 	mvebu_writel(port, 0, PCIE_WIN5_CTRL_OFF);
193 	mvebu_writel(port, 0, PCIE_WIN5_BASE_OFF);
194 	mvebu_writel(port, 0, PCIE_WIN5_REMAP_OFF);
195 }
196 
197 /*
198  * Setup PCIE BARs and Address Decode Wins:
199  * BAR[0] -> internal registers (needed for MSI)
200  * BAR[1] -> covers all DRAM banks
201  * BAR[2] -> Disabled
202  * WIN[0-3] -> DRAM bank[0-3]
203  */
mvebu_pcie_setup_wins(struct mvebu_pcie_port * port)204 static void mvebu_pcie_setup_wins(struct mvebu_pcie_port *port)
205 {
206 	const struct mbus_dram_target_info *dram;
207 	u32 size;
208 	int i;
209 
210 	dram = mv_mbus_dram_info();
211 
212 	/* First, disable and clear BARs and windows. */
213 	mvebu_pcie_disable_wins(port);
214 
215 	/* Setup windows for DDR banks.  Count total DDR size on the fly. */
216 	size = 0;
217 	for (i = 0; i < dram->num_cs; i++) {
218 		const struct mbus_dram_window *cs = dram->cs + i;
219 
220 		mvebu_writel(port, cs->base & 0xffff0000,
221 			     PCIE_WIN04_BASE_OFF(i));
222 		mvebu_writel(port, 0, PCIE_WIN04_REMAP_OFF(i));
223 		mvebu_writel(port,
224 			     ((cs->size - 1) & 0xffff0000) |
225 			     (cs->mbus_attr << 8) |
226 			     (dram->mbus_dram_target_id << 4) | 1,
227 			     PCIE_WIN04_CTRL_OFF(i));
228 
229 		size += cs->size;
230 	}
231 
232 	/* Round up 'size' to the nearest power of two. */
233 	if ((size & (size - 1)) != 0)
234 		size = 1 << fls(size);
235 
236 	/* Setup BAR[1] to all DRAM banks. */
237 	mvebu_writel(port, dram->cs[0].base, PCIE_BAR_LO_OFF(1));
238 	mvebu_writel(port, 0, PCIE_BAR_HI_OFF(1));
239 	mvebu_writel(port, ((size - 1) & 0xffff0000) | 1,
240 		     PCIE_BAR_CTRL_OFF(1));
241 
242 	/*
243 	 * Point BAR[0] to the device's internal registers.
244 	 */
245 	mvebu_writel(port, round_down(port->regs.start, SZ_1M), PCIE_BAR_LO_OFF(0));
246 	mvebu_writel(port, 0, PCIE_BAR_HI_OFF(0));
247 }
248 
mvebu_pcie_setup_hw(struct mvebu_pcie_port * port)249 static void mvebu_pcie_setup_hw(struct mvebu_pcie_port *port)
250 {
251 	u32 ctrl, lnkcap, cmd, dev_rev, unmask, sspl;
252 
253 	/* Setup PCIe controller to Root Complex mode. */
254 	ctrl = mvebu_readl(port, PCIE_CTRL_OFF);
255 	ctrl |= PCIE_CTRL_RC_MODE;
256 	mvebu_writel(port, ctrl, PCIE_CTRL_OFF);
257 
258 	/*
259 	 * Set Maximum Link Width to X1 or X4 in Root Port's PCIe Link
260 	 * Capability register. This register is defined by PCIe specification
261 	 * as read-only but this mvebu controller has it as read-write and must
262 	 * be set to number of SerDes PCIe lanes (1 or 4). If this register is
263 	 * not set correctly then link with endpoint card is not established.
264 	 */
265 	lnkcap = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCAP);
266 	lnkcap &= ~PCI_EXP_LNKCAP_MLW;
267 	lnkcap |= FIELD_PREP(PCI_EXP_LNKCAP_MLW, port->is_x4 ? 4 : 1);
268 	mvebu_writel(port, lnkcap, PCIE_CAP_PCIEXP + PCI_EXP_LNKCAP);
269 
270 	/* Disable Root Bridge I/O space, memory space and bus mastering. */
271 	cmd = mvebu_readl(port, PCIE_CMD_OFF);
272 	cmd &= ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
273 	mvebu_writel(port, cmd, PCIE_CMD_OFF);
274 
275 	/*
276 	 * Change Class Code of PCI Bridge device to PCI Bridge (0x6004)
277 	 * because default value is Memory controller (0x5080).
278 	 *
279 	 * Note that this mvebu PCI Bridge does not have compliant Type 1
280 	 * Configuration Space. Header Type is reported as Type 0 and it
281 	 * has format of Type 0 config space.
282 	 *
283 	 * Moreover Type 0 BAR registers (ranges 0x10 - 0x28 and 0x30 - 0x34)
284 	 * have the same format in Marvell's specification as in PCIe
285 	 * specification, but their meaning is totally different and they do
286 	 * different things: they are aliased into internal mvebu registers
287 	 * (e.g. PCIE_BAR_LO_OFF) and these should not be changed or
288 	 * reconfigured by pci device drivers.
289 	 *
290 	 * Therefore driver uses emulation of PCI Bridge which emulates
291 	 * access to configuration space via internal mvebu registers or
292 	 * emulated configuration buffer. Driver access these PCI Bridge
293 	 * directly for simplification, but these registers can be accessed
294 	 * also via standard mvebu way for accessing PCI config space.
295 	 */
296 	dev_rev = mvebu_readl(port, PCIE_DEV_REV_OFF);
297 	dev_rev &= ~0xffffff00;
298 	dev_rev |= PCI_CLASS_BRIDGE_PCI_NORMAL << 8;
299 	mvebu_writel(port, dev_rev, PCIE_DEV_REV_OFF);
300 
301 	/* Point PCIe unit MBUS decode windows to DRAM space. */
302 	mvebu_pcie_setup_wins(port);
303 
304 	/*
305 	 * Program Root Port to automatically send Set_Slot_Power_Limit
306 	 * PCIe Message when changing status from Dl_Down to Dl_Up and valid
307 	 * slot power limit was specified.
308 	 */
309 	sspl = mvebu_readl(port, PCIE_SSPL_OFF);
310 	sspl &= ~(PCIE_SSPL_VALUE_MASK | PCIE_SSPL_SCALE_MASK | PCIE_SSPL_ENABLE);
311 	if (port->slot_power_limit_value) {
312 		sspl |= port->slot_power_limit_value << PCIE_SSPL_VALUE_SHIFT;
313 		sspl |= port->slot_power_limit_scale << PCIE_SSPL_SCALE_SHIFT;
314 		sspl |= PCIE_SSPL_ENABLE;
315 	}
316 	mvebu_writel(port, sspl, PCIE_SSPL_OFF);
317 
318 	/* Mask all interrupt sources. */
319 	mvebu_writel(port, ~PCIE_INT_ALL_MASK, PCIE_INT_UNMASK_OFF);
320 
321 	/* Clear all interrupt causes. */
322 	mvebu_writel(port, ~PCIE_INT_ALL_MASK, PCIE_INT_CAUSE_OFF);
323 
324 	/* Check if "intx" interrupt was specified in DT. */
325 	if (port->intx_irq > 0)
326 		return;
327 
328 	/*
329 	 * Fallback code when "intx" interrupt was not specified in DT:
330 	 * Unmask all legacy INTx interrupts as driver does not provide a way
331 	 * for masking and unmasking of individual legacy INTx interrupts.
332 	 * Legacy INTx are reported via one shared GIC source and therefore
333 	 * kernel cannot distinguish which individual legacy INTx was triggered.
334 	 * These interrupts are shared, so it should not cause any issue. Just
335 	 * performance penalty as every PCIe interrupt handler needs to be
336 	 * called when some interrupt is triggered.
337 	 */
338 	unmask = mvebu_readl(port, PCIE_INT_UNMASK_OFF);
339 	unmask |= PCIE_INT_INTX(0) | PCIE_INT_INTX(1) |
340 		  PCIE_INT_INTX(2) | PCIE_INT_INTX(3);
341 	mvebu_writel(port, unmask, PCIE_INT_UNMASK_OFF);
342 }
343 
344 static struct mvebu_pcie_port *mvebu_pcie_find_port(struct mvebu_pcie *pcie,
345 						    struct pci_bus *bus,
346 						    int devfn);
347 
mvebu_pcie_child_rd_conf(struct pci_bus * bus,u32 devfn,int where,int size,u32 * val)348 static int mvebu_pcie_child_rd_conf(struct pci_bus *bus, u32 devfn, int where,
349 				    int size, u32 *val)
350 {
351 	struct mvebu_pcie *pcie = bus->sysdata;
352 	struct mvebu_pcie_port *port;
353 	void __iomem *conf_data;
354 
355 	port = mvebu_pcie_find_port(pcie, bus, devfn);
356 	if (!port)
357 		return PCIBIOS_DEVICE_NOT_FOUND;
358 
359 	if (!mvebu_pcie_link_up(port))
360 		return PCIBIOS_DEVICE_NOT_FOUND;
361 
362 	conf_data = port->base + PCIE_CONF_DATA_OFF;
363 
364 	mvebu_writel(port, PCIE_CONF_ADDR(bus->number, devfn, where),
365 		     PCIE_CONF_ADDR_OFF);
366 
367 	switch (size) {
368 	case 1:
369 		*val = readb_relaxed(conf_data + (where & 3));
370 		break;
371 	case 2:
372 		*val = readw_relaxed(conf_data + (where & 2));
373 		break;
374 	case 4:
375 		*val = readl_relaxed(conf_data);
376 		break;
377 	default:
378 		return PCIBIOS_BAD_REGISTER_NUMBER;
379 	}
380 
381 	return PCIBIOS_SUCCESSFUL;
382 }
383 
mvebu_pcie_child_wr_conf(struct pci_bus * bus,u32 devfn,int where,int size,u32 val)384 static int mvebu_pcie_child_wr_conf(struct pci_bus *bus, u32 devfn,
385 				    int where, int size, u32 val)
386 {
387 	struct mvebu_pcie *pcie = bus->sysdata;
388 	struct mvebu_pcie_port *port;
389 	void __iomem *conf_data;
390 
391 	port = mvebu_pcie_find_port(pcie, bus, devfn);
392 	if (!port)
393 		return PCIBIOS_DEVICE_NOT_FOUND;
394 
395 	if (!mvebu_pcie_link_up(port))
396 		return PCIBIOS_DEVICE_NOT_FOUND;
397 
398 	conf_data = port->base + PCIE_CONF_DATA_OFF;
399 
400 	mvebu_writel(port, PCIE_CONF_ADDR(bus->number, devfn, where),
401 		     PCIE_CONF_ADDR_OFF);
402 
403 	switch (size) {
404 	case 1:
405 		writeb(val, conf_data + (where & 3));
406 		break;
407 	case 2:
408 		writew(val, conf_data + (where & 2));
409 		break;
410 	case 4:
411 		writel(val, conf_data);
412 		break;
413 	default:
414 		return PCIBIOS_BAD_REGISTER_NUMBER;
415 	}
416 
417 	return PCIBIOS_SUCCESSFUL;
418 }
419 
420 static struct pci_ops mvebu_pcie_child_ops = {
421 	.read = mvebu_pcie_child_rd_conf,
422 	.write = mvebu_pcie_child_wr_conf,
423 };
424 
425 /*
426  * Remove windows, starting from the largest ones to the smallest
427  * ones.
428  */
mvebu_pcie_del_windows(struct mvebu_pcie_port * port,phys_addr_t base,size_t size)429 static void mvebu_pcie_del_windows(struct mvebu_pcie_port *port,
430 				   phys_addr_t base, size_t size)
431 {
432 	while (size) {
433 		size_t sz = 1 << (fls(size) - 1);
434 
435 		mvebu_mbus_del_window(base, sz);
436 		base += sz;
437 		size -= sz;
438 	}
439 }
440 
441 /*
442  * MBus windows can only have a power of two size, but PCI BARs do not
443  * have this constraint. Therefore, we have to split the PCI BAR into
444  * areas each having a power of two size. We start from the largest
445  * one (i.e highest order bit set in the size).
446  */
mvebu_pcie_add_windows(struct mvebu_pcie_port * port,unsigned int target,unsigned int attribute,phys_addr_t base,size_t size,phys_addr_t remap)447 static int mvebu_pcie_add_windows(struct mvebu_pcie_port *port,
448 				   unsigned int target, unsigned int attribute,
449 				   phys_addr_t base, size_t size,
450 				   phys_addr_t remap)
451 {
452 	size_t size_mapped = 0;
453 
454 	while (size) {
455 		size_t sz = 1 << (fls(size) - 1);
456 		int ret;
457 
458 		ret = mvebu_mbus_add_window_remap_by_id(target, attribute, base,
459 							sz, remap);
460 		if (ret) {
461 			phys_addr_t end = base + sz - 1;
462 
463 			dev_err(&port->pcie->pdev->dev,
464 				"Could not create MBus window at [mem %pa-%pa]: %d\n",
465 				&base, &end, ret);
466 			mvebu_pcie_del_windows(port, base - size_mapped,
467 					       size_mapped);
468 			return ret;
469 		}
470 
471 		size -= sz;
472 		size_mapped += sz;
473 		base += sz;
474 		if (remap != MVEBU_MBUS_NO_REMAP)
475 			remap += sz;
476 	}
477 
478 	return 0;
479 }
480 
mvebu_pcie_set_window(struct mvebu_pcie_port * port,unsigned int target,unsigned int attribute,const struct mvebu_pcie_window * desired,struct mvebu_pcie_window * cur)481 static int mvebu_pcie_set_window(struct mvebu_pcie_port *port,
482 				  unsigned int target, unsigned int attribute,
483 				  const struct mvebu_pcie_window *desired,
484 				  struct mvebu_pcie_window *cur)
485 {
486 	int ret;
487 
488 	if (desired->base == cur->base && desired->remap == cur->remap &&
489 	    desired->size == cur->size)
490 		return 0;
491 
492 	if (cur->size != 0) {
493 		mvebu_pcie_del_windows(port, cur->base, cur->size);
494 		cur->size = 0;
495 		cur->base = 0;
496 
497 		/*
498 		 * If something tries to change the window while it is enabled
499 		 * the change will not be done atomically. That would be
500 		 * difficult to do in the general case.
501 		 */
502 	}
503 
504 	if (desired->size == 0)
505 		return 0;
506 
507 	ret = mvebu_pcie_add_windows(port, target, attribute, desired->base,
508 				     desired->size, desired->remap);
509 	if (ret) {
510 		cur->size = 0;
511 		cur->base = 0;
512 		return ret;
513 	}
514 
515 	*cur = *desired;
516 	return 0;
517 }
518 
mvebu_pcie_handle_iobase_change(struct mvebu_pcie_port * port)519 static int mvebu_pcie_handle_iobase_change(struct mvebu_pcie_port *port)
520 {
521 	struct mvebu_pcie_window desired = {};
522 	struct pci_bridge_emul_conf *conf = &port->bridge.conf;
523 
524 	/* Are the new iobase/iolimit values invalid? */
525 	if (conf->iolimit < conf->iobase ||
526 	    le16_to_cpu(conf->iolimitupper) < le16_to_cpu(conf->iobaseupper))
527 		return mvebu_pcie_set_window(port, port->io_target, port->io_attr,
528 					     &desired, &port->iowin);
529 
530 	/*
531 	 * We read the PCI-to-PCI bridge emulated registers, and
532 	 * calculate the base address and size of the address decoding
533 	 * window to setup, according to the PCI-to-PCI bridge
534 	 * specifications. iobase is the bus address, port->iowin_base
535 	 * is the CPU address.
536 	 */
537 	desired.remap = ((conf->iobase & 0xF0) << 8) |
538 			(le16_to_cpu(conf->iobaseupper) << 16);
539 	desired.base = port->pcie->io.start + desired.remap;
540 	desired.size = ((0xFFF | ((conf->iolimit & 0xF0) << 8) |
541 			 (le16_to_cpu(conf->iolimitupper) << 16)) -
542 			desired.remap) +
543 		       1;
544 
545 	return mvebu_pcie_set_window(port, port->io_target, port->io_attr, &desired,
546 				     &port->iowin);
547 }
548 
mvebu_pcie_handle_membase_change(struct mvebu_pcie_port * port)549 static int mvebu_pcie_handle_membase_change(struct mvebu_pcie_port *port)
550 {
551 	struct mvebu_pcie_window desired = {.remap = MVEBU_MBUS_NO_REMAP};
552 	struct pci_bridge_emul_conf *conf = &port->bridge.conf;
553 
554 	/* Are the new membase/memlimit values invalid? */
555 	if (le16_to_cpu(conf->memlimit) < le16_to_cpu(conf->membase))
556 		return mvebu_pcie_set_window(port, port->mem_target, port->mem_attr,
557 					     &desired, &port->memwin);
558 
559 	/*
560 	 * We read the PCI-to-PCI bridge emulated registers, and
561 	 * calculate the base address and size of the address decoding
562 	 * window to setup, according to the PCI-to-PCI bridge
563 	 * specifications.
564 	 */
565 	desired.base = ((le16_to_cpu(conf->membase) & 0xFFF0) << 16);
566 	desired.size = (((le16_to_cpu(conf->memlimit) & 0xFFF0) << 16) | 0xFFFFF) -
567 		       desired.base + 1;
568 
569 	return mvebu_pcie_set_window(port, port->mem_target, port->mem_attr, &desired,
570 				     &port->memwin);
571 }
572 
573 static pci_bridge_emul_read_status_t
mvebu_pci_bridge_emul_base_conf_read(struct pci_bridge_emul * bridge,int reg,u32 * value)574 mvebu_pci_bridge_emul_base_conf_read(struct pci_bridge_emul *bridge,
575 				     int reg, u32 *value)
576 {
577 	struct mvebu_pcie_port *port = bridge->data;
578 
579 	switch (reg) {
580 	case PCI_COMMAND:
581 		*value = mvebu_readl(port, PCIE_CMD_OFF);
582 		break;
583 
584 	case PCI_PRIMARY_BUS: {
585 		/*
586 		 * From the whole 32bit register we support reading from HW only
587 		 * secondary bus number which is mvebu local bus number.
588 		 * Other bits are retrieved only from emulated config buffer.
589 		 */
590 		__le32 *cfgspace = (__le32 *)&bridge->conf;
591 		u32 val = le32_to_cpu(cfgspace[PCI_PRIMARY_BUS / 4]);
592 		val &= ~0xff00;
593 		val |= mvebu_pcie_get_local_bus_nr(port) << 8;
594 		*value = val;
595 		break;
596 	}
597 
598 	case PCI_INTERRUPT_LINE: {
599 		/*
600 		 * From the whole 32bit register we support reading from HW only
601 		 * one bit: PCI_BRIDGE_CTL_BUS_RESET.
602 		 * Other bits are retrieved only from emulated config buffer.
603 		 */
604 		__le32 *cfgspace = (__le32 *)&bridge->conf;
605 		u32 val = le32_to_cpu(cfgspace[PCI_INTERRUPT_LINE / 4]);
606 		if (mvebu_readl(port, PCIE_CTRL_OFF) & PCIE_CTRL_MASTER_HOT_RESET)
607 			val |= PCI_BRIDGE_CTL_BUS_RESET << 16;
608 		else
609 			val &= ~(PCI_BRIDGE_CTL_BUS_RESET << 16);
610 		*value = val;
611 		break;
612 	}
613 
614 	default:
615 		return PCI_BRIDGE_EMUL_NOT_HANDLED;
616 	}
617 
618 	return PCI_BRIDGE_EMUL_HANDLED;
619 }
620 
621 static pci_bridge_emul_read_status_t
mvebu_pci_bridge_emul_pcie_conf_read(struct pci_bridge_emul * bridge,int reg,u32 * value)622 mvebu_pci_bridge_emul_pcie_conf_read(struct pci_bridge_emul *bridge,
623 				     int reg, u32 *value)
624 {
625 	struct mvebu_pcie_port *port = bridge->data;
626 
627 	switch (reg) {
628 	case PCI_EXP_DEVCAP:
629 		*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCAP);
630 		break;
631 
632 	case PCI_EXP_DEVCTL:
633 		*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL);
634 		break;
635 
636 	case PCI_EXP_LNKCAP:
637 		/*
638 		 * PCIe requires that the Clock Power Management capability bit
639 		 * is hard-wired to zero for downstream ports but HW returns 1.
640 		 * Additionally enable Data Link Layer Link Active Reporting
641 		 * Capable bit as DL_Active indication is provided too.
642 		 */
643 		*value = (mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCAP) &
644 			  ~PCI_EXP_LNKCAP_CLKPM) | PCI_EXP_LNKCAP_DLLLARC;
645 		break;
646 
647 	case PCI_EXP_LNKCTL:
648 		/* DL_Active indication is provided via PCIE_STAT_OFF */
649 		*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL) |
650 			 (mvebu_pcie_link_up(port) ?
651 			  (PCI_EXP_LNKSTA_DLLLA << 16) : 0);
652 		break;
653 
654 	case PCI_EXP_SLTCTL: {
655 		u16 slotctl = le16_to_cpu(bridge->pcie_conf.slotctl);
656 		u16 slotsta = le16_to_cpu(bridge->pcie_conf.slotsta);
657 		u32 val = 0;
658 		/*
659 		 * When slot power limit was not specified in DT then
660 		 * ASPL_DISABLE bit is stored only in emulated config space.
661 		 * Otherwise reflect status of PCIE_SSPL_ENABLE bit in HW.
662 		 */
663 		if (!port->slot_power_limit_value)
664 			val |= slotctl & PCI_EXP_SLTCTL_ASPL_DISABLE;
665 		else if (!(mvebu_readl(port, PCIE_SSPL_OFF) & PCIE_SSPL_ENABLE))
666 			val |= PCI_EXP_SLTCTL_ASPL_DISABLE;
667 		/* This callback is 32-bit and in high bits is slot status. */
668 		val |= slotsta << 16;
669 		*value = val;
670 		break;
671 	}
672 
673 	case PCI_EXP_RTSTA:
674 		*value = mvebu_readl(port, PCIE_RC_RTSTA);
675 		break;
676 
677 	case PCI_EXP_DEVCAP2:
678 		*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCAP2);
679 		break;
680 
681 	case PCI_EXP_DEVCTL2:
682 		*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL2);
683 		break;
684 
685 	case PCI_EXP_LNKCTL2:
686 		*value = mvebu_readl(port, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL2);
687 		break;
688 
689 	default:
690 		return PCI_BRIDGE_EMUL_NOT_HANDLED;
691 	}
692 
693 	return PCI_BRIDGE_EMUL_HANDLED;
694 }
695 
696 static pci_bridge_emul_read_status_t
mvebu_pci_bridge_emul_ext_conf_read(struct pci_bridge_emul * bridge,int reg,u32 * value)697 mvebu_pci_bridge_emul_ext_conf_read(struct pci_bridge_emul *bridge,
698 				    int reg, u32 *value)
699 {
700 	struct mvebu_pcie_port *port = bridge->data;
701 
702 	switch (reg) {
703 	case 0:
704 	case PCI_ERR_UNCOR_STATUS:
705 	case PCI_ERR_UNCOR_MASK:
706 	case PCI_ERR_UNCOR_SEVER:
707 	case PCI_ERR_COR_STATUS:
708 	case PCI_ERR_COR_MASK:
709 	case PCI_ERR_CAP:
710 	case PCI_ERR_HEADER_LOG+0:
711 	case PCI_ERR_HEADER_LOG+4:
712 	case PCI_ERR_HEADER_LOG+8:
713 	case PCI_ERR_HEADER_LOG+12:
714 	case PCI_ERR_ROOT_COMMAND:
715 	case PCI_ERR_ROOT_STATUS:
716 	case PCI_ERR_ROOT_ERR_SRC:
717 		*value = mvebu_readl(port, PCIE_CAP_PCIERR_OFF + reg);
718 		break;
719 
720 	default:
721 		return PCI_BRIDGE_EMUL_NOT_HANDLED;
722 	}
723 
724 	return PCI_BRIDGE_EMUL_HANDLED;
725 }
726 
727 static void
mvebu_pci_bridge_emul_base_conf_write(struct pci_bridge_emul * bridge,int reg,u32 old,u32 new,u32 mask)728 mvebu_pci_bridge_emul_base_conf_write(struct pci_bridge_emul *bridge,
729 				      int reg, u32 old, u32 new, u32 mask)
730 {
731 	struct mvebu_pcie_port *port = bridge->data;
732 	struct pci_bridge_emul_conf *conf = &bridge->conf;
733 
734 	switch (reg) {
735 	case PCI_COMMAND:
736 		mvebu_writel(port, new, PCIE_CMD_OFF);
737 		break;
738 
739 	case PCI_IO_BASE:
740 		if ((mask & 0xffff) && mvebu_has_ioport(port) &&
741 		    mvebu_pcie_handle_iobase_change(port)) {
742 			/* On error disable IO range */
743 			conf->iobase &= ~0xf0;
744 			conf->iolimit &= ~0xf0;
745 			conf->iobase |= 0xf0;
746 			conf->iobaseupper = cpu_to_le16(0x0000);
747 			conf->iolimitupper = cpu_to_le16(0x0000);
748 		}
749 		break;
750 
751 	case PCI_MEMORY_BASE:
752 		if (mvebu_pcie_handle_membase_change(port)) {
753 			/* On error disable mem range */
754 			conf->membase = cpu_to_le16(le16_to_cpu(conf->membase) & ~0xfff0);
755 			conf->memlimit = cpu_to_le16(le16_to_cpu(conf->memlimit) & ~0xfff0);
756 			conf->membase = cpu_to_le16(le16_to_cpu(conf->membase) | 0xfff0);
757 		}
758 		break;
759 
760 	case PCI_IO_BASE_UPPER16:
761 		if (mvebu_has_ioport(port) &&
762 		    mvebu_pcie_handle_iobase_change(port)) {
763 			/* On error disable IO range */
764 			conf->iobase &= ~0xf0;
765 			conf->iolimit &= ~0xf0;
766 			conf->iobase |= 0xf0;
767 			conf->iobaseupper = cpu_to_le16(0x0000);
768 			conf->iolimitupper = cpu_to_le16(0x0000);
769 		}
770 		break;
771 
772 	case PCI_PRIMARY_BUS:
773 		if (mask & 0xff00)
774 			mvebu_pcie_set_local_bus_nr(port, conf->secondary_bus);
775 		break;
776 
777 	case PCI_INTERRUPT_LINE:
778 		if (mask & (PCI_BRIDGE_CTL_BUS_RESET << 16)) {
779 			u32 ctrl = mvebu_readl(port, PCIE_CTRL_OFF);
780 			if (new & (PCI_BRIDGE_CTL_BUS_RESET << 16))
781 				ctrl |= PCIE_CTRL_MASTER_HOT_RESET;
782 			else
783 				ctrl &= ~PCIE_CTRL_MASTER_HOT_RESET;
784 			mvebu_writel(port, ctrl, PCIE_CTRL_OFF);
785 		}
786 		break;
787 
788 	default:
789 		break;
790 	}
791 }
792 
793 static void
mvebu_pci_bridge_emul_pcie_conf_write(struct pci_bridge_emul * bridge,int reg,u32 old,u32 new,u32 mask)794 mvebu_pci_bridge_emul_pcie_conf_write(struct pci_bridge_emul *bridge,
795 				      int reg, u32 old, u32 new, u32 mask)
796 {
797 	struct mvebu_pcie_port *port = bridge->data;
798 
799 	switch (reg) {
800 	case PCI_EXP_DEVCTL:
801 		mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL);
802 		break;
803 
804 	case PCI_EXP_LNKCTL:
805 		/*
806 		 * PCIe requires that the Enable Clock Power Management bit
807 		 * is hard-wired to zero for downstream ports but HW allows
808 		 * to change it.
809 		 */
810 		new &= ~PCI_EXP_LNKCTL_CLKREQ_EN;
811 
812 		mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL);
813 		break;
814 
815 	case PCI_EXP_SLTCTL:
816 		/*
817 		 * Allow to change PCIE_SSPL_ENABLE bit only when slot power
818 		 * limit was specified in DT and configured into HW.
819 		 */
820 		if ((mask & PCI_EXP_SLTCTL_ASPL_DISABLE) &&
821 		    port->slot_power_limit_value) {
822 			u32 sspl = mvebu_readl(port, PCIE_SSPL_OFF);
823 			if (new & PCI_EXP_SLTCTL_ASPL_DISABLE)
824 				sspl &= ~PCIE_SSPL_ENABLE;
825 			else
826 				sspl |= PCIE_SSPL_ENABLE;
827 			mvebu_writel(port, sspl, PCIE_SSPL_OFF);
828 		}
829 		break;
830 
831 	case PCI_EXP_RTSTA:
832 		/*
833 		 * PME Status bit in Root Status Register (PCIE_RC_RTSTA)
834 		 * is read-only and can be cleared only by writing 0b to the
835 		 * Interrupt Cause RW0C register (PCIE_INT_CAUSE_OFF). So
836 		 * clear PME via Interrupt Cause.
837 		 */
838 		if (new & PCI_EXP_RTSTA_PME)
839 			mvebu_writel(port, ~PCIE_INT_PM_PME, PCIE_INT_CAUSE_OFF);
840 		break;
841 
842 	case PCI_EXP_DEVCTL2:
843 		mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_DEVCTL2);
844 		break;
845 
846 	case PCI_EXP_LNKCTL2:
847 		mvebu_writel(port, new, PCIE_CAP_PCIEXP + PCI_EXP_LNKCTL2);
848 		break;
849 
850 	default:
851 		break;
852 	}
853 }
854 
855 static void
mvebu_pci_bridge_emul_ext_conf_write(struct pci_bridge_emul * bridge,int reg,u32 old,u32 new,u32 mask)856 mvebu_pci_bridge_emul_ext_conf_write(struct pci_bridge_emul *bridge,
857 				     int reg, u32 old, u32 new, u32 mask)
858 {
859 	struct mvebu_pcie_port *port = bridge->data;
860 
861 	switch (reg) {
862 	/* These are W1C registers, so clear other bits */
863 	case PCI_ERR_UNCOR_STATUS:
864 	case PCI_ERR_COR_STATUS:
865 	case PCI_ERR_ROOT_STATUS:
866 		new &= mask;
867 		fallthrough;
868 
869 	case PCI_ERR_UNCOR_MASK:
870 	case PCI_ERR_UNCOR_SEVER:
871 	case PCI_ERR_COR_MASK:
872 	case PCI_ERR_CAP:
873 	case PCI_ERR_HEADER_LOG+0:
874 	case PCI_ERR_HEADER_LOG+4:
875 	case PCI_ERR_HEADER_LOG+8:
876 	case PCI_ERR_HEADER_LOG+12:
877 	case PCI_ERR_ROOT_COMMAND:
878 	case PCI_ERR_ROOT_ERR_SRC:
879 		mvebu_writel(port, new, PCIE_CAP_PCIERR_OFF + reg);
880 		break;
881 
882 	default:
883 		break;
884 	}
885 }
886 
887 static const struct pci_bridge_emul_ops mvebu_pci_bridge_emul_ops = {
888 	.read_base = mvebu_pci_bridge_emul_base_conf_read,
889 	.write_base = mvebu_pci_bridge_emul_base_conf_write,
890 	.read_pcie = mvebu_pci_bridge_emul_pcie_conf_read,
891 	.write_pcie = mvebu_pci_bridge_emul_pcie_conf_write,
892 	.read_ext = mvebu_pci_bridge_emul_ext_conf_read,
893 	.write_ext = mvebu_pci_bridge_emul_ext_conf_write,
894 };
895 
896 /*
897  * Initialize the configuration space of the PCI-to-PCI bridge
898  * associated with the given PCIe interface.
899  */
mvebu_pci_bridge_emul_init(struct mvebu_pcie_port * port)900 static int mvebu_pci_bridge_emul_init(struct mvebu_pcie_port *port)
901 {
902 	unsigned int bridge_flags = PCI_BRIDGE_EMUL_NO_PREFMEM_FORWARD;
903 	struct pci_bridge_emul *bridge = &port->bridge;
904 	u32 dev_id = mvebu_readl(port, PCIE_DEV_ID_OFF);
905 	u32 dev_rev = mvebu_readl(port, PCIE_DEV_REV_OFF);
906 	u32 ssdev_id = mvebu_readl(port, PCIE_SSDEV_ID_OFF);
907 	u32 pcie_cap = mvebu_readl(port, PCIE_CAP_PCIEXP);
908 	u8 pcie_cap_ver = ((pcie_cap >> 16) & PCI_EXP_FLAGS_VERS);
909 
910 	bridge->conf.vendor = cpu_to_le16(dev_id & 0xffff);
911 	bridge->conf.device = cpu_to_le16(dev_id >> 16);
912 	bridge->conf.class_revision = cpu_to_le32(dev_rev & 0xff);
913 
914 	if (mvebu_has_ioport(port)) {
915 		/* We support 32 bits I/O addressing */
916 		bridge->conf.iobase = PCI_IO_RANGE_TYPE_32;
917 		bridge->conf.iolimit = PCI_IO_RANGE_TYPE_32;
918 	} else {
919 		bridge_flags |= PCI_BRIDGE_EMUL_NO_IO_FORWARD;
920 	}
921 
922 	/*
923 	 * Older mvebu hardware provides PCIe Capability structure only in
924 	 * version 1. New hardware provides it in version 2.
925 	 * Enable slot support which is emulated.
926 	 */
927 	bridge->pcie_conf.cap = cpu_to_le16(pcie_cap_ver | PCI_EXP_FLAGS_SLOT);
928 
929 	/*
930 	 * Set Presence Detect State bit permanently as there is no support for
931 	 * unplugging PCIe card from the slot. Assume that PCIe card is always
932 	 * connected in slot.
933 	 *
934 	 * Set physical slot number to port+1 as mvebu ports are indexed from
935 	 * zero and zero value is reserved for ports within the same silicon
936 	 * as Root Port which is not mvebu case.
937 	 *
938 	 * Also set correct slot power limit.
939 	 */
940 	bridge->pcie_conf.slotcap = cpu_to_le32(
941 		FIELD_PREP(PCI_EXP_SLTCAP_SPLV, port->slot_power_limit_value) |
942 		FIELD_PREP(PCI_EXP_SLTCAP_SPLS, port->slot_power_limit_scale) |
943 		FIELD_PREP(PCI_EXP_SLTCAP_PSN, port->port+1));
944 	bridge->pcie_conf.slotsta = cpu_to_le16(PCI_EXP_SLTSTA_PDS);
945 
946 	bridge->subsystem_vendor_id = ssdev_id & 0xffff;
947 	bridge->subsystem_id = ssdev_id >> 16;
948 	bridge->has_pcie = true;
949 	bridge->pcie_start = PCIE_CAP_PCIEXP;
950 	bridge->data = port;
951 	bridge->ops = &mvebu_pci_bridge_emul_ops;
952 
953 	return pci_bridge_emul_init(bridge, bridge_flags);
954 }
955 
sys_to_pcie(struct pci_sys_data * sys)956 static inline struct mvebu_pcie *sys_to_pcie(struct pci_sys_data *sys)
957 {
958 	return sys->private_data;
959 }
960 
mvebu_pcie_find_port(struct mvebu_pcie * pcie,struct pci_bus * bus,int devfn)961 static struct mvebu_pcie_port *mvebu_pcie_find_port(struct mvebu_pcie *pcie,
962 						    struct pci_bus *bus,
963 						    int devfn)
964 {
965 	int i;
966 
967 	for (i = 0; i < pcie->nports; i++) {
968 		struct mvebu_pcie_port *port = &pcie->ports[i];
969 
970 		if (!port->base)
971 			continue;
972 
973 		if (bus->number == 0 && port->devfn == devfn)
974 			return port;
975 		if (bus->number != 0 &&
976 		    bus->number >= port->bridge.conf.secondary_bus &&
977 		    bus->number <= port->bridge.conf.subordinate_bus)
978 			return port;
979 	}
980 
981 	return NULL;
982 }
983 
984 /* PCI configuration space write function */
mvebu_pcie_wr_conf(struct pci_bus * bus,u32 devfn,int where,int size,u32 val)985 static int mvebu_pcie_wr_conf(struct pci_bus *bus, u32 devfn,
986 			      int where, int size, u32 val)
987 {
988 	struct mvebu_pcie *pcie = bus->sysdata;
989 	struct mvebu_pcie_port *port;
990 
991 	port = mvebu_pcie_find_port(pcie, bus, devfn);
992 	if (!port)
993 		return PCIBIOS_DEVICE_NOT_FOUND;
994 
995 	return pci_bridge_emul_conf_write(&port->bridge, where, size, val);
996 }
997 
998 /* PCI configuration space read function */
mvebu_pcie_rd_conf(struct pci_bus * bus,u32 devfn,int where,int size,u32 * val)999 static int mvebu_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
1000 			      int size, u32 *val)
1001 {
1002 	struct mvebu_pcie *pcie = bus->sysdata;
1003 	struct mvebu_pcie_port *port;
1004 
1005 	port = mvebu_pcie_find_port(pcie, bus, devfn);
1006 	if (!port)
1007 		return PCIBIOS_DEVICE_NOT_FOUND;
1008 
1009 	return pci_bridge_emul_conf_read(&port->bridge, where, size, val);
1010 }
1011 
1012 static struct pci_ops mvebu_pcie_ops = {
1013 	.read = mvebu_pcie_rd_conf,
1014 	.write = mvebu_pcie_wr_conf,
1015 };
1016 
mvebu_pcie_intx_irq_mask(struct irq_data * d)1017 static void mvebu_pcie_intx_irq_mask(struct irq_data *d)
1018 {
1019 	struct mvebu_pcie_port *port = d->domain->host_data;
1020 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
1021 	unsigned long flags;
1022 	u32 unmask;
1023 
1024 	raw_spin_lock_irqsave(&port->irq_lock, flags);
1025 	unmask = mvebu_readl(port, PCIE_INT_UNMASK_OFF);
1026 	unmask &= ~PCIE_INT_INTX(hwirq);
1027 	mvebu_writel(port, unmask, PCIE_INT_UNMASK_OFF);
1028 	raw_spin_unlock_irqrestore(&port->irq_lock, flags);
1029 }
1030 
mvebu_pcie_intx_irq_unmask(struct irq_data * d)1031 static void mvebu_pcie_intx_irq_unmask(struct irq_data *d)
1032 {
1033 	struct mvebu_pcie_port *port = d->domain->host_data;
1034 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
1035 	unsigned long flags;
1036 	u32 unmask;
1037 
1038 	raw_spin_lock_irqsave(&port->irq_lock, flags);
1039 	unmask = mvebu_readl(port, PCIE_INT_UNMASK_OFF);
1040 	unmask |= PCIE_INT_INTX(hwirq);
1041 	mvebu_writel(port, unmask, PCIE_INT_UNMASK_OFF);
1042 	raw_spin_unlock_irqrestore(&port->irq_lock, flags);
1043 }
1044 
1045 static struct irq_chip intx_irq_chip = {
1046 	.name = "mvebu-INTx",
1047 	.irq_mask = mvebu_pcie_intx_irq_mask,
1048 	.irq_unmask = mvebu_pcie_intx_irq_unmask,
1049 };
1050 
mvebu_pcie_intx_irq_map(struct irq_domain * h,unsigned int virq,irq_hw_number_t hwirq)1051 static int mvebu_pcie_intx_irq_map(struct irq_domain *h,
1052 				   unsigned int virq, irq_hw_number_t hwirq)
1053 {
1054 	struct mvebu_pcie_port *port = h->host_data;
1055 
1056 	irq_set_status_flags(virq, IRQ_LEVEL);
1057 	irq_set_chip_and_handler(virq, &intx_irq_chip, handle_level_irq);
1058 	irq_set_chip_data(virq, port);
1059 
1060 	return 0;
1061 }
1062 
1063 static const struct irq_domain_ops mvebu_pcie_intx_irq_domain_ops = {
1064 	.map = mvebu_pcie_intx_irq_map,
1065 	.xlate = irq_domain_xlate_onecell,
1066 };
1067 
mvebu_pcie_init_irq_domain(struct mvebu_pcie_port * port)1068 static int mvebu_pcie_init_irq_domain(struct mvebu_pcie_port *port)
1069 {
1070 	struct device *dev = &port->pcie->pdev->dev;
1071 	struct device_node *pcie_intc_node;
1072 
1073 	raw_spin_lock_init(&port->irq_lock);
1074 
1075 	pcie_intc_node = of_get_next_child(port->dn, NULL);
1076 	if (!pcie_intc_node) {
1077 		dev_err(dev, "No PCIe Intc node found for %s\n", port->name);
1078 		return -ENODEV;
1079 	}
1080 
1081 	port->intx_irq_domain = irq_domain_add_linear(pcie_intc_node, PCI_NUM_INTX,
1082 						      &mvebu_pcie_intx_irq_domain_ops,
1083 						      port);
1084 	of_node_put(pcie_intc_node);
1085 	if (!port->intx_irq_domain) {
1086 		dev_err(dev, "Failed to get INTx IRQ domain for %s\n", port->name);
1087 		return -ENOMEM;
1088 	}
1089 
1090 	return 0;
1091 }
1092 
mvebu_pcie_irq_handler(struct irq_desc * desc)1093 static void mvebu_pcie_irq_handler(struct irq_desc *desc)
1094 {
1095 	struct mvebu_pcie_port *port = irq_desc_get_handler_data(desc);
1096 	struct irq_chip *chip = irq_desc_get_chip(desc);
1097 	struct device *dev = &port->pcie->pdev->dev;
1098 	u32 cause, unmask, status;
1099 	int i;
1100 
1101 	chained_irq_enter(chip, desc);
1102 
1103 	cause = mvebu_readl(port, PCIE_INT_CAUSE_OFF);
1104 	unmask = mvebu_readl(port, PCIE_INT_UNMASK_OFF);
1105 	status = cause & unmask;
1106 
1107 	/* Process legacy INTx interrupts */
1108 	for (i = 0; i < PCI_NUM_INTX; i++) {
1109 		if (!(status & PCIE_INT_INTX(i)))
1110 			continue;
1111 
1112 		if (generic_handle_domain_irq(port->intx_irq_domain, i) == -EINVAL)
1113 			dev_err_ratelimited(dev, "unexpected INT%c IRQ\n", (char)i+'A');
1114 	}
1115 
1116 	chained_irq_exit(chip, desc);
1117 }
1118 
mvebu_pcie_map_irq(const struct pci_dev * dev,u8 slot,u8 pin)1119 static int mvebu_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
1120 {
1121 	/* Interrupt support on mvebu emulated bridges is not implemented yet */
1122 	if (dev->bus->number == 0)
1123 		return 0; /* Proper return code 0 == NO_IRQ */
1124 
1125 	return of_irq_parse_and_map_pci(dev, slot, pin);
1126 }
1127 
mvebu_pcie_align_resource(struct pci_dev * dev,const struct resource * res,resource_size_t start,resource_size_t size,resource_size_t align)1128 static resource_size_t mvebu_pcie_align_resource(struct pci_dev *dev,
1129 						 const struct resource *res,
1130 						 resource_size_t start,
1131 						 resource_size_t size,
1132 						 resource_size_t align)
1133 {
1134 	if (dev->bus->number != 0)
1135 		return start;
1136 
1137 	/*
1138 	 * On the PCI-to-PCI bridge side, the I/O windows must have at
1139 	 * least a 64 KB size and the memory windows must have at
1140 	 * least a 1 MB size. Moreover, MBus windows need to have a
1141 	 * base address aligned on their size, and their size must be
1142 	 * a power of two. This means that if the BAR doesn't have a
1143 	 * power of two size, several MBus windows will actually be
1144 	 * created. We need to ensure that the biggest MBus window
1145 	 * (which will be the first one) is aligned on its size, which
1146 	 * explains the rounddown_pow_of_two() being done here.
1147 	 */
1148 	if (res->flags & IORESOURCE_IO)
1149 		return round_up(start, max_t(resource_size_t, SZ_64K,
1150 					     rounddown_pow_of_two(size)));
1151 	else if (res->flags & IORESOURCE_MEM)
1152 		return round_up(start, max_t(resource_size_t, SZ_1M,
1153 					     rounddown_pow_of_two(size)));
1154 	else
1155 		return start;
1156 }
1157 
mvebu_pcie_map_registers(struct platform_device * pdev,struct device_node * np,struct mvebu_pcie_port * port)1158 static void __iomem *mvebu_pcie_map_registers(struct platform_device *pdev,
1159 					      struct device_node *np,
1160 					      struct mvebu_pcie_port *port)
1161 {
1162 	int ret = 0;
1163 
1164 	ret = of_address_to_resource(np, 0, &port->regs);
1165 	if (ret)
1166 		return (void __iomem *)ERR_PTR(ret);
1167 
1168 	return devm_ioremap_resource(&pdev->dev, &port->regs);
1169 }
1170 
1171 #define DT_FLAGS_TO_TYPE(flags)       (((flags) >> 24) & 0x03)
1172 #define    DT_TYPE_IO                 0x1
1173 #define    DT_TYPE_MEM32              0x2
1174 #define DT_CPUADDR_TO_TARGET(cpuaddr) (((cpuaddr) >> 56) & 0xFF)
1175 #define DT_CPUADDR_TO_ATTR(cpuaddr)   (((cpuaddr) >> 48) & 0xFF)
1176 
mvebu_get_tgt_attr(struct device_node * np,int devfn,unsigned long type,unsigned int * tgt,unsigned int * attr)1177 static int mvebu_get_tgt_attr(struct device_node *np, int devfn,
1178 			      unsigned long type,
1179 			      unsigned int *tgt,
1180 			      unsigned int *attr)
1181 {
1182 	const int na = 3, ns = 2;
1183 	const __be32 *range;
1184 	int rlen, nranges, rangesz, pna, i;
1185 
1186 	*tgt = -1;
1187 	*attr = -1;
1188 
1189 	range = of_get_property(np, "ranges", &rlen);
1190 	if (!range)
1191 		return -EINVAL;
1192 
1193 	pna = of_n_addr_cells(np);
1194 	rangesz = pna + na + ns;
1195 	nranges = rlen / sizeof(__be32) / rangesz;
1196 
1197 	for (i = 0; i < nranges; i++, range += rangesz) {
1198 		u32 flags = of_read_number(range, 1);
1199 		u32 slot = of_read_number(range + 1, 1);
1200 		u64 cpuaddr = of_read_number(range + na, pna);
1201 		unsigned long rtype;
1202 
1203 		if (DT_FLAGS_TO_TYPE(flags) == DT_TYPE_IO)
1204 			rtype = IORESOURCE_IO;
1205 		else if (DT_FLAGS_TO_TYPE(flags) == DT_TYPE_MEM32)
1206 			rtype = IORESOURCE_MEM;
1207 		else
1208 			continue;
1209 
1210 		if (slot == PCI_SLOT(devfn) && type == rtype) {
1211 			*tgt = DT_CPUADDR_TO_TARGET(cpuaddr);
1212 			*attr = DT_CPUADDR_TO_ATTR(cpuaddr);
1213 			return 0;
1214 		}
1215 	}
1216 
1217 	return -ENOENT;
1218 }
1219 
mvebu_pcie_suspend(struct device * dev)1220 static int mvebu_pcie_suspend(struct device *dev)
1221 {
1222 	struct mvebu_pcie *pcie;
1223 	int i;
1224 
1225 	pcie = dev_get_drvdata(dev);
1226 	for (i = 0; i < pcie->nports; i++) {
1227 		struct mvebu_pcie_port *port = pcie->ports + i;
1228 		if (!port->base)
1229 			continue;
1230 		port->saved_pcie_stat = mvebu_readl(port, PCIE_STAT_OFF);
1231 	}
1232 
1233 	return 0;
1234 }
1235 
mvebu_pcie_resume(struct device * dev)1236 static int mvebu_pcie_resume(struct device *dev)
1237 {
1238 	struct mvebu_pcie *pcie;
1239 	int i;
1240 
1241 	pcie = dev_get_drvdata(dev);
1242 	for (i = 0; i < pcie->nports; i++) {
1243 		struct mvebu_pcie_port *port = pcie->ports + i;
1244 		if (!port->base)
1245 			continue;
1246 		mvebu_writel(port, port->saved_pcie_stat, PCIE_STAT_OFF);
1247 		mvebu_pcie_setup_hw(port);
1248 	}
1249 
1250 	return 0;
1251 }
1252 
mvebu_pcie_port_clk_put(void * data)1253 static void mvebu_pcie_port_clk_put(void *data)
1254 {
1255 	struct mvebu_pcie_port *port = data;
1256 
1257 	clk_put(port->clk);
1258 }
1259 
mvebu_pcie_parse_port(struct mvebu_pcie * pcie,struct mvebu_pcie_port * port,struct device_node * child)1260 static int mvebu_pcie_parse_port(struct mvebu_pcie *pcie,
1261 	struct mvebu_pcie_port *port, struct device_node *child)
1262 {
1263 	struct device *dev = &pcie->pdev->dev;
1264 	u32 slot_power_limit;
1265 	int ret;
1266 	u32 num_lanes;
1267 
1268 	port->pcie = pcie;
1269 
1270 	if (of_property_read_u32(child, "marvell,pcie-port", &port->port)) {
1271 		dev_warn(dev, "ignoring %pOF, missing pcie-port property\n",
1272 			 child);
1273 		goto skip;
1274 	}
1275 
1276 	if (of_property_read_u32(child, "marvell,pcie-lane", &port->lane))
1277 		port->lane = 0;
1278 
1279 	if (!of_property_read_u32(child, "num-lanes", &num_lanes) && num_lanes == 4)
1280 		port->is_x4 = true;
1281 
1282 	port->name = devm_kasprintf(dev, GFP_KERNEL, "pcie%d.%d", port->port,
1283 				    port->lane);
1284 	if (!port->name) {
1285 		ret = -ENOMEM;
1286 		goto err;
1287 	}
1288 
1289 	port->devfn = of_pci_get_devfn(child);
1290 	if (port->devfn < 0)
1291 		goto skip;
1292 	if (PCI_FUNC(port->devfn) != 0) {
1293 		dev_err(dev, "%s: invalid function number, must be zero\n",
1294 			port->name);
1295 		goto skip;
1296 	}
1297 
1298 	ret = mvebu_get_tgt_attr(dev->of_node, port->devfn, IORESOURCE_MEM,
1299 				 &port->mem_target, &port->mem_attr);
1300 	if (ret < 0) {
1301 		dev_err(dev, "%s: cannot get tgt/attr for mem window\n",
1302 			port->name);
1303 		goto skip;
1304 	}
1305 
1306 	if (resource_size(&pcie->io) != 0) {
1307 		mvebu_get_tgt_attr(dev->of_node, port->devfn, IORESOURCE_IO,
1308 				   &port->io_target, &port->io_attr);
1309 	} else {
1310 		port->io_target = -1;
1311 		port->io_attr = -1;
1312 	}
1313 
1314 	/*
1315 	 * Old DT bindings do not contain "intx" interrupt
1316 	 * so do not fail probing driver when interrupt does not exist.
1317 	 */
1318 	port->intx_irq = of_irq_get_byname(child, "intx");
1319 	if (port->intx_irq == -EPROBE_DEFER) {
1320 		ret = port->intx_irq;
1321 		goto err;
1322 	}
1323 	if (port->intx_irq <= 0) {
1324 		dev_warn(dev, "%s: legacy INTx interrupts cannot be masked individually, "
1325 			      "%pOF does not contain intx interrupt\n",
1326 			 port->name, child);
1327 	}
1328 
1329 	port->reset_name = devm_kasprintf(dev, GFP_KERNEL, "%s-reset",
1330 					  port->name);
1331 	if (!port->reset_name) {
1332 		ret = -ENOMEM;
1333 		goto err;
1334 	}
1335 
1336 	port->reset_gpio = devm_fwnode_gpiod_get(dev, of_fwnode_handle(child),
1337 						 "reset", GPIOD_OUT_HIGH,
1338 						 port->name);
1339 	ret = PTR_ERR_OR_ZERO(port->reset_gpio);
1340 	if (ret) {
1341 		if (ret != -ENOENT)
1342 			goto err;
1343 		/* reset gpio is optional */
1344 		port->reset_gpio = NULL;
1345 		devm_kfree(dev, port->reset_name);
1346 		port->reset_name = NULL;
1347 	}
1348 
1349 	slot_power_limit = of_pci_get_slot_power_limit(child,
1350 				&port->slot_power_limit_value,
1351 				&port->slot_power_limit_scale);
1352 	if (slot_power_limit)
1353 		dev_info(dev, "%s: Slot power limit %u.%uW\n",
1354 			 port->name,
1355 			 slot_power_limit / 1000,
1356 			 (slot_power_limit / 100) % 10);
1357 
1358 	port->clk = of_clk_get_by_name(child, NULL);
1359 	if (IS_ERR(port->clk)) {
1360 		dev_err(dev, "%s: cannot get clock\n", port->name);
1361 		goto skip;
1362 	}
1363 
1364 	ret = devm_add_action(dev, mvebu_pcie_port_clk_put, port);
1365 	if (ret < 0) {
1366 		clk_put(port->clk);
1367 		goto err;
1368 	}
1369 
1370 	return 1;
1371 
1372 skip:
1373 	ret = 0;
1374 
1375 	/* In the case of skipping, we need to free these */
1376 	devm_kfree(dev, port->reset_name);
1377 	port->reset_name = NULL;
1378 	devm_kfree(dev, port->name);
1379 	port->name = NULL;
1380 
1381 err:
1382 	return ret;
1383 }
1384 
1385 /*
1386  * Power up a PCIe port.  PCIe requires the refclk to be stable for 100µs
1387  * prior to releasing PERST.  See table 2-4 in section 2.6.2 AC Specifications
1388  * of the PCI Express Card Electromechanical Specification, 1.1.
1389  */
mvebu_pcie_powerup(struct mvebu_pcie_port * port)1390 static int mvebu_pcie_powerup(struct mvebu_pcie_port *port)
1391 {
1392 	int ret;
1393 
1394 	ret = clk_prepare_enable(port->clk);
1395 	if (ret < 0)
1396 		return ret;
1397 
1398 	if (port->reset_gpio) {
1399 		u32 reset_udelay = PCI_PM_D3COLD_WAIT * 1000;
1400 
1401 		of_property_read_u32(port->dn, "reset-delay-us",
1402 				     &reset_udelay);
1403 
1404 		udelay(100);
1405 
1406 		gpiod_set_value_cansleep(port->reset_gpio, 0);
1407 		msleep(reset_udelay / 1000);
1408 	}
1409 
1410 	return 0;
1411 }
1412 
1413 /*
1414  * Power down a PCIe port.  Strictly, PCIe requires us to place the card
1415  * in D3hot state before asserting PERST#.
1416  */
mvebu_pcie_powerdown(struct mvebu_pcie_port * port)1417 static void mvebu_pcie_powerdown(struct mvebu_pcie_port *port)
1418 {
1419 	gpiod_set_value_cansleep(port->reset_gpio, 1);
1420 
1421 	clk_disable_unprepare(port->clk);
1422 }
1423 
1424 /*
1425  * devm_of_pci_get_host_bridge_resources() only sets up translateable resources,
1426  * so we need extra resource setup parsing our special DT properties encoding
1427  * the MEM and IO apertures.
1428  */
mvebu_pcie_parse_request_resources(struct mvebu_pcie * pcie)1429 static int mvebu_pcie_parse_request_resources(struct mvebu_pcie *pcie)
1430 {
1431 	struct device *dev = &pcie->pdev->dev;
1432 	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
1433 	int ret;
1434 
1435 	/* Get the PCIe memory aperture */
1436 	mvebu_mbus_get_pcie_mem_aperture(&pcie->mem);
1437 	if (resource_size(&pcie->mem) == 0) {
1438 		dev_err(dev, "invalid memory aperture size\n");
1439 		return -EINVAL;
1440 	}
1441 
1442 	pcie->mem.name = "PCI MEM";
1443 	pci_add_resource(&bridge->windows, &pcie->mem);
1444 	ret = devm_request_resource(dev, &iomem_resource, &pcie->mem);
1445 	if (ret)
1446 		return ret;
1447 
1448 	/* Get the PCIe IO aperture */
1449 	mvebu_mbus_get_pcie_io_aperture(&pcie->io);
1450 
1451 	if (resource_size(&pcie->io) != 0) {
1452 		pcie->realio.flags = pcie->io.flags;
1453 		pcie->realio.start = PCIBIOS_MIN_IO;
1454 		pcie->realio.end = min_t(resource_size_t,
1455 					 IO_SPACE_LIMIT - SZ_64K,
1456 					 resource_size(&pcie->io) - 1);
1457 		pcie->realio.name = "PCI I/O";
1458 
1459 		ret = devm_pci_remap_iospace(dev, &pcie->realio, pcie->io.start);
1460 		if (ret)
1461 			return ret;
1462 
1463 		pci_add_resource(&bridge->windows, &pcie->realio);
1464 		ret = devm_request_resource(dev, &ioport_resource, &pcie->realio);
1465 		if (ret)
1466 			return ret;
1467 	}
1468 
1469 	return 0;
1470 }
1471 
mvebu_pcie_probe(struct platform_device * pdev)1472 static int mvebu_pcie_probe(struct platform_device *pdev)
1473 {
1474 	struct device *dev = &pdev->dev;
1475 	struct mvebu_pcie *pcie;
1476 	struct pci_host_bridge *bridge;
1477 	struct device_node *np = dev->of_node;
1478 	struct device_node *child;
1479 	int num, i, ret;
1480 
1481 	bridge = devm_pci_alloc_host_bridge(dev, sizeof(struct mvebu_pcie));
1482 	if (!bridge)
1483 		return -ENOMEM;
1484 
1485 	pcie = pci_host_bridge_priv(bridge);
1486 	pcie->pdev = pdev;
1487 	platform_set_drvdata(pdev, pcie);
1488 
1489 	ret = mvebu_pcie_parse_request_resources(pcie);
1490 	if (ret)
1491 		return ret;
1492 
1493 	num = of_get_available_child_count(np);
1494 
1495 	pcie->ports = devm_kcalloc(dev, num, sizeof(*pcie->ports), GFP_KERNEL);
1496 	if (!pcie->ports)
1497 		return -ENOMEM;
1498 
1499 	i = 0;
1500 	for_each_available_child_of_node(np, child) {
1501 		struct mvebu_pcie_port *port = &pcie->ports[i];
1502 
1503 		ret = mvebu_pcie_parse_port(pcie, port, child);
1504 		if (ret < 0) {
1505 			of_node_put(child);
1506 			return ret;
1507 		} else if (ret == 0) {
1508 			continue;
1509 		}
1510 
1511 		port->dn = child;
1512 		i++;
1513 	}
1514 	pcie->nports = i;
1515 
1516 	for (i = 0; i < pcie->nports; i++) {
1517 		struct mvebu_pcie_port *port = &pcie->ports[i];
1518 		int irq = port->intx_irq;
1519 
1520 		child = port->dn;
1521 		if (!child)
1522 			continue;
1523 
1524 		ret = mvebu_pcie_powerup(port);
1525 		if (ret < 0)
1526 			continue;
1527 
1528 		port->base = mvebu_pcie_map_registers(pdev, child, port);
1529 		if (IS_ERR(port->base)) {
1530 			dev_err(dev, "%s: cannot map registers\n", port->name);
1531 			port->base = NULL;
1532 			mvebu_pcie_powerdown(port);
1533 			continue;
1534 		}
1535 
1536 		ret = mvebu_pci_bridge_emul_init(port);
1537 		if (ret < 0) {
1538 			dev_err(dev, "%s: cannot init emulated bridge\n",
1539 				port->name);
1540 			devm_iounmap(dev, port->base);
1541 			port->base = NULL;
1542 			mvebu_pcie_powerdown(port);
1543 			continue;
1544 		}
1545 
1546 		if (irq > 0) {
1547 			ret = mvebu_pcie_init_irq_domain(port);
1548 			if (ret) {
1549 				dev_err(dev, "%s: cannot init irq domain\n",
1550 					port->name);
1551 				pci_bridge_emul_cleanup(&port->bridge);
1552 				devm_iounmap(dev, port->base);
1553 				port->base = NULL;
1554 				mvebu_pcie_powerdown(port);
1555 				continue;
1556 			}
1557 			irq_set_chained_handler_and_data(irq,
1558 							 mvebu_pcie_irq_handler,
1559 							 port);
1560 		}
1561 
1562 		/*
1563 		 * PCIe topology exported by mvebu hw is quite complicated. In
1564 		 * reality has something like N fully independent host bridges
1565 		 * where each host bridge has one PCIe Root Port (which acts as
1566 		 * PCI Bridge device). Each host bridge has its own independent
1567 		 * internal registers, independent access to PCI config space,
1568 		 * independent interrupt lines, independent window and memory
1569 		 * access configuration. But additionally there is some kind of
1570 		 * peer-to-peer support between PCIe devices behind different
1571 		 * host bridges limited just to forwarding of memory and I/O
1572 		 * transactions (forwarding of error messages and config cycles
1573 		 * is not supported). So we could say there are N independent
1574 		 * PCIe Root Complexes.
1575 		 *
1576 		 * For this kind of setup DT should have been structured into
1577 		 * N independent PCIe controllers / host bridges. But instead
1578 		 * structure in past was defined to put PCIe Root Ports of all
1579 		 * host bridges into one bus zero, like in classic multi-port
1580 		 * Root Complex setup with just one host bridge.
1581 		 *
1582 		 * This means that pci-mvebu.c driver provides "virtual" bus 0
1583 		 * on which registers all PCIe Root Ports (PCI Bridge devices)
1584 		 * specified in DT by their BDF addresses and virtually routes
1585 		 * PCI config access of each PCI bridge device to specific PCIe
1586 		 * host bridge.
1587 		 *
1588 		 * Normally PCI Bridge should choose between Type 0 and Type 1
1589 		 * config requests based on primary and secondary bus numbers
1590 		 * configured on the bridge itself. But because mvebu PCI Bridge
1591 		 * does not have registers for primary and secondary bus numbers
1592 		 * in its config space, it determinates type of config requests
1593 		 * via its own custom way.
1594 		 *
1595 		 * There are two options how mvebu determinate type of config
1596 		 * request.
1597 		 *
1598 		 * 1. If Secondary Bus Number Enable bit is not set or is not
1599 		 * available (applies for pre-XP PCIe controllers) then Type 0
1600 		 * is used if target bus number equals Local Bus Number (bits
1601 		 * [15:8] in register 0x1a04) and target device number differs
1602 		 * from Local Device Number (bits [20:16] in register 0x1a04).
1603 		 * Type 1 is used if target bus number differs from Local Bus
1604 		 * Number. And when target bus number equals Local Bus Number
1605 		 * and target device equals Local Device Number then request is
1606 		 * routed to Local PCI Bridge (PCIe Root Port).
1607 		 *
1608 		 * 2. If Secondary Bus Number Enable bit is set (bit 7 in
1609 		 * register 0x1a2c) then mvebu hw determinate type of config
1610 		 * request like compliant PCI Bridge based on primary bus number
1611 		 * which is configured via Local Bus Number (bits [15:8] in
1612 		 * register 0x1a04) and secondary bus number which is configured
1613 		 * via Secondary Bus Number (bits [7:0] in register 0x1a2c).
1614 		 * Local PCI Bridge (PCIe Root Port) is available on primary bus
1615 		 * as device with Local Device Number (bits [20:16] in register
1616 		 * 0x1a04).
1617 		 *
1618 		 * Secondary Bus Number Enable bit is disabled by default and
1619 		 * option 2. is not available on pre-XP PCIe controllers. Hence
1620 		 * this driver always use option 1.
1621 		 *
1622 		 * Basically it means that primary and secondary buses shares
1623 		 * one virtual number configured via Local Bus Number bits and
1624 		 * Local Device Number bits determinates if accessing primary
1625 		 * or secondary bus. Set Local Device Number to 1 and redirect
1626 		 * all writes of PCI Bridge Secondary Bus Number register to
1627 		 * Local Bus Number (bits [15:8] in register 0x1a04).
1628 		 *
1629 		 * So when accessing devices on buses behind secondary bus
1630 		 * number it would work correctly. And also when accessing
1631 		 * device 0 at secondary bus number via config space would be
1632 		 * correctly routed to secondary bus. Due to issues described
1633 		 * in mvebu_pcie_setup_hw(), PCI Bridges at primary bus (zero)
1634 		 * are not accessed directly via PCI config space but rarher
1635 		 * indirectly via kernel emulated PCI bridge driver.
1636 		 */
1637 		mvebu_pcie_setup_hw(port);
1638 		mvebu_pcie_set_local_dev_nr(port, 1);
1639 		mvebu_pcie_set_local_bus_nr(port, 0);
1640 	}
1641 
1642 	bridge->sysdata = pcie;
1643 	bridge->ops = &mvebu_pcie_ops;
1644 	bridge->child_ops = &mvebu_pcie_child_ops;
1645 	bridge->align_resource = mvebu_pcie_align_resource;
1646 	bridge->map_irq = mvebu_pcie_map_irq;
1647 
1648 	return pci_host_probe(bridge);
1649 }
1650 
mvebu_pcie_remove(struct platform_device * pdev)1651 static void mvebu_pcie_remove(struct platform_device *pdev)
1652 {
1653 	struct mvebu_pcie *pcie = platform_get_drvdata(pdev);
1654 	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
1655 	u32 cmd, sspl;
1656 	int i;
1657 
1658 	/* Remove PCI bus with all devices. */
1659 	pci_lock_rescan_remove();
1660 	pci_stop_root_bus(bridge->bus);
1661 	pci_remove_root_bus(bridge->bus);
1662 	pci_unlock_rescan_remove();
1663 
1664 	for (i = 0; i < pcie->nports; i++) {
1665 		struct mvebu_pcie_port *port = &pcie->ports[i];
1666 		int irq = port->intx_irq;
1667 
1668 		if (!port->base)
1669 			continue;
1670 
1671 		/* Disable Root Bridge I/O space, memory space and bus mastering. */
1672 		cmd = mvebu_readl(port, PCIE_CMD_OFF);
1673 		cmd &= ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
1674 		mvebu_writel(port, cmd, PCIE_CMD_OFF);
1675 
1676 		/* Mask all interrupt sources. */
1677 		mvebu_writel(port, ~PCIE_INT_ALL_MASK, PCIE_INT_UNMASK_OFF);
1678 
1679 		/* Clear all interrupt causes. */
1680 		mvebu_writel(port, ~PCIE_INT_ALL_MASK, PCIE_INT_CAUSE_OFF);
1681 
1682 		if (irq > 0)
1683 			irq_set_chained_handler_and_data(irq, NULL, NULL);
1684 
1685 		/* Remove IRQ domains. */
1686 		if (port->intx_irq_domain)
1687 			irq_domain_remove(port->intx_irq_domain);
1688 
1689 		/* Free config space for emulated root bridge. */
1690 		pci_bridge_emul_cleanup(&port->bridge);
1691 
1692 		/* Disable sending Set_Slot_Power_Limit PCIe Message. */
1693 		sspl = mvebu_readl(port, PCIE_SSPL_OFF);
1694 		sspl &= ~(PCIE_SSPL_VALUE_MASK | PCIE_SSPL_SCALE_MASK | PCIE_SSPL_ENABLE);
1695 		mvebu_writel(port, sspl, PCIE_SSPL_OFF);
1696 
1697 		/* Disable and clear BARs and windows. */
1698 		mvebu_pcie_disable_wins(port);
1699 
1700 		/* Delete PCIe IO and MEM windows. */
1701 		if (port->iowin.size)
1702 			mvebu_pcie_del_windows(port, port->iowin.base, port->iowin.size);
1703 		if (port->memwin.size)
1704 			mvebu_pcie_del_windows(port, port->memwin.base, port->memwin.size);
1705 
1706 		/* Power down card and disable clocks. Must be the last step. */
1707 		mvebu_pcie_powerdown(port);
1708 	}
1709 }
1710 
1711 static const struct of_device_id mvebu_pcie_of_match_table[] = {
1712 	{ .compatible = "marvell,armada-xp-pcie", },
1713 	{ .compatible = "marvell,armada-370-pcie", },
1714 	{ .compatible = "marvell,dove-pcie", },
1715 	{ .compatible = "marvell,kirkwood-pcie", },
1716 	{},
1717 };
1718 
1719 static const struct dev_pm_ops mvebu_pcie_pm_ops = {
1720 	NOIRQ_SYSTEM_SLEEP_PM_OPS(mvebu_pcie_suspend, mvebu_pcie_resume)
1721 };
1722 
1723 static struct platform_driver mvebu_pcie_driver = {
1724 	.driver = {
1725 		.name = "mvebu-pcie",
1726 		.of_match_table = mvebu_pcie_of_match_table,
1727 		.pm = &mvebu_pcie_pm_ops,
1728 	},
1729 	.probe = mvebu_pcie_probe,
1730 	.remove_new = mvebu_pcie_remove,
1731 };
1732 module_platform_driver(mvebu_pcie_driver);
1733 
1734 MODULE_AUTHOR("Thomas Petazzoni <thomas.petazzoni@bootlin.com>");
1735 MODULE_AUTHOR("Pali Rohár <pali@kernel.org>");
1736 MODULE_DESCRIPTION("Marvell EBU PCIe controller");
1737 MODULE_LICENSE("GPL v2");
1738