xref: /openbmc/u-boot/drivers/pci/pcie_dw_mvebu.c (revision cd1cc31f)
1 /*
2  * Copyright (C) 2015 Marvell International Ltd.
3  *
4  * Copyright (C) 2016 Stefan Roese <sr@denx.de>
5  *
6  * Based on:
7  *   - drivers/pci/pcie_imx.c
8  *   - drivers/pci/pci_mvebu.c
9  *   - drivers/pci/pcie_xilinx.c
10  *
11  * SPDX-License-Identifier:	GPL-2.0+
12  */
13 
14 #include <common.h>
15 #include <dm.h>
16 #include <pci.h>
17 #include <asm/io.h>
18 #include <asm-generic/gpio.h>
19 
20 DECLARE_GLOBAL_DATA_PTR;
21 
22 /* PCI Config space registers */
23 #define PCIE_CONFIG_BAR0		0x10
24 #define PCIE_LINK_STATUS_REG		0x80
25 #define PCIE_LINK_STATUS_SPEED_OFF	16
26 #define PCIE_LINK_STATUS_SPEED_MASK	(0xf << PCIE_LINK_STATUS_SPEED_OFF)
27 #define PCIE_LINK_STATUS_WIDTH_OFF	20
28 #define PCIE_LINK_STATUS_WIDTH_MASK	(0xf << PCIE_LINK_STATUS_WIDTH_OFF)
29 
30 /* Resizable bar capability registers */
31 #define RESIZABLE_BAR_CAP		0x250
32 #define RESIZABLE_BAR_CTL0		0x254
33 #define RESIZABLE_BAR_CTL1		0x258
34 
35 /* iATU registers */
36 #define PCIE_ATU_VIEWPORT		0x900
37 #define PCIE_ATU_REGION_INBOUND		(0x1 << 31)
38 #define PCIE_ATU_REGION_OUTBOUND	(0x0 << 31)
39 #define PCIE_ATU_REGION_INDEX1		(0x1 << 0)
40 #define PCIE_ATU_REGION_INDEX0		(0x0 << 0)
41 #define PCIE_ATU_CR1			0x904
42 #define PCIE_ATU_TYPE_MEM		(0x0 << 0)
43 #define PCIE_ATU_TYPE_IO		(0x2 << 0)
44 #define PCIE_ATU_TYPE_CFG0		(0x4 << 0)
45 #define PCIE_ATU_TYPE_CFG1		(0x5 << 0)
46 #define PCIE_ATU_CR2			0x908
47 #define PCIE_ATU_ENABLE			(0x1 << 31)
48 #define PCIE_ATU_BAR_MODE_ENABLE	(0x1 << 30)
49 #define PCIE_ATU_LOWER_BASE		0x90C
50 #define PCIE_ATU_UPPER_BASE		0x910
51 #define PCIE_ATU_LIMIT			0x914
52 #define PCIE_ATU_LOWER_TARGET		0x918
53 #define PCIE_ATU_BUS(x)			(((x) & 0xff) << 24)
54 #define PCIE_ATU_DEV(x)			(((x) & 0x1f) << 19)
55 #define PCIE_ATU_FUNC(x)		(((x) & 0x7) << 16)
56 #define PCIE_ATU_UPPER_TARGET		0x91C
57 
58 #define PCIE_LINK_CAPABILITY		0x7C
59 #define PCIE_LINK_CTL_2			0xA0
60 #define TARGET_LINK_SPEED_MASK		0xF
61 #define LINK_SPEED_GEN_1		0x1
62 #define LINK_SPEED_GEN_2		0x2
63 #define LINK_SPEED_GEN_3		0x3
64 
65 #define PCIE_GEN3_RELATED		0x890
66 #define GEN3_EQU_DISABLE		(1 << 16)
67 #define GEN3_ZRXDC_NON_COMP		(1 << 0)
68 
69 #define PCIE_GEN3_EQU_CTRL		0x8A8
70 #define GEN3_EQU_EVAL_2MS_DISABLE	(1 << 5)
71 
72 #define PCIE_ROOT_COMPLEX_MODE_MASK	(0xF << 4)
73 
74 #define PCIE_LINK_UP_TIMEOUT_MS		100
75 
76 #define PCIE_GLOBAL_CONTROL		0x8000
77 #define PCIE_APP_LTSSM_EN		(1 << 2)
78 #define PCIE_DEVICE_TYPE_OFFSET		(4)
79 #define PCIE_DEVICE_TYPE_MASK		(0xF)
80 #define PCIE_DEVICE_TYPE_EP		(0x0) /* Endpoint */
81 #define PCIE_DEVICE_TYPE_LEP		(0x1) /* Legacy endpoint */
82 #define PCIE_DEVICE_TYPE_RC		(0x4) /* Root complex */
83 
84 #define PCIE_GLOBAL_STATUS		0x8008
85 #define PCIE_GLB_STS_RDLH_LINK_UP	(1 << 1)
86 #define PCIE_GLB_STS_PHY_LINK_UP	(1 << 9)
87 
88 #define PCIE_ARCACHE_TRC		0x8050
89 #define PCIE_AWCACHE_TRC		0x8054
90 #define ARCACHE_SHAREABLE_CACHEABLE	0x3511
91 #define AWCACHE_SHAREABLE_CACHEABLE	0x5311
92 
93 #define LINK_SPEED_GEN_1                0x1
94 #define LINK_SPEED_GEN_2                0x2
95 #define LINK_SPEED_GEN_3                0x3
96 
97 /**
98  * struct pcie_dw_mvebu - MVEBU DW PCIe controller state
99  *
100  * @ctrl_base: The base address of the register space
101  * @cfg_base: The base address of the configuration space
102  * @cfg_size: The size of the configuration space which is needed
103  *            as it gets written into the PCIE_ATU_LIMIT register
104  * @first_busno: This driver supports multiple PCIe controllers.
105  *               first_busno stores the bus number of the PCIe root-port
106  *               number which may vary depending on the PCIe setup
107  *               (PEX switches etc).
108  */
109 struct pcie_dw_mvebu {
110 	void *ctrl_base;
111 	void *cfg_base;
112 	fdt_size_t cfg_size;
113 	int first_busno;
114 };
115 
116 static int pcie_dw_get_link_speed(const void *regs_base)
117 {
118 	return (readl(regs_base + PCIE_LINK_STATUS_REG) &
119 		PCIE_LINK_STATUS_SPEED_MASK) >> PCIE_LINK_STATUS_SPEED_OFF;
120 }
121 
122 static int pcie_dw_get_link_width(const void *regs_base)
123 {
124 	return (readl(regs_base + PCIE_LINK_STATUS_REG) &
125 		PCIE_LINK_STATUS_WIDTH_MASK) >> PCIE_LINK_STATUS_WIDTH_OFF;
126 }
127 
128 /**
129  * set_cfg_address() - Configure the PCIe controller config space access
130  *
131  * @pcie: Pointer to the PCI controller state
132  * @d: PCI device to access
133  * @where: Offset in the configuration space
134  *
135  * Configures the PCIe controller to access the configuration space of
136  * a specific PCIe device and returns the address to use for this
137  * access.
138  *
139  * Return: Address that can be used to access the configation space
140  *         of the requested device / offset
141  */
142 static uintptr_t set_cfg_address(struct pcie_dw_mvebu *pcie,
143 				 pci_dev_t d, uint where)
144 {
145 	uintptr_t va_address;
146 
147 	/*
148 	 * Region #0 is used for Outbound CFG space access.
149 	 * Direction = Outbound
150 	 * Region Index = 0
151 	 */
152 	writel(0, pcie->ctrl_base + PCIE_ATU_VIEWPORT);
153 
154 	if (PCI_BUS(d) == (pcie->first_busno + 1))
155 		/* For local bus, change TLP Type field to 4. */
156 		writel(PCIE_ATU_TYPE_CFG0, pcie->ctrl_base + PCIE_ATU_CR1);
157 	else
158 		/* Otherwise, change TLP Type field to 5. */
159 		writel(PCIE_ATU_TYPE_CFG1, pcie->ctrl_base + PCIE_ATU_CR1);
160 
161 	if (PCI_BUS(d) == pcie->first_busno) {
162 		/* Accessing root port configuration space. */
163 		va_address = (uintptr_t)pcie->ctrl_base;
164 	} else {
165 		d = PCI_MASK_BUS(d) | (PCI_BUS(d) - pcie->first_busno);
166 		writel(d << 8, pcie->ctrl_base + PCIE_ATU_LOWER_TARGET);
167 		va_address = (uintptr_t)pcie->cfg_base;
168 	}
169 
170 	va_address += where & ~0x3;
171 
172 	return va_address;
173 }
174 
175 /**
176  * pcie_dw_addr_valid() - Check for valid bus address
177  *
178  * @d: The PCI device to access
179  * @first_busno: Bus number of the PCIe controller root complex
180  *
181  * Return 1 (true) if the PCI device can be accessed by this controller.
182  *
183  * Return: 1 on valid, 0 on invalid
184  */
185 static int pcie_dw_addr_valid(pci_dev_t d, int first_busno)
186 {
187 	if ((PCI_BUS(d) == first_busno) && (PCI_DEV(d) > 0))
188 		return 0;
189 	if ((PCI_BUS(d) == first_busno + 1) && (PCI_DEV(d) > 0))
190 		return 0;
191 
192 	return 1;
193 }
194 
195 /**
196  * pcie_dw_mvebu_read_config() - Read from configuration space
197  *
198  * @bus: Pointer to the PCI bus
199  * @bdf: Identifies the PCIe device to access
200  * @offset: The offset into the device's configuration space
201  * @valuep: A pointer at which to store the read value
202  * @size: Indicates the size of access to perform
203  *
204  * Read a value of size @size from offset @offset within the configuration
205  * space of the device identified by the bus, device & function numbers in @bdf
206  * on the PCI bus @bus.
207  *
208  * Return: 0 on success
209  */
210 static int pcie_dw_mvebu_read_config(struct udevice *bus, pci_dev_t bdf,
211 				     uint offset, ulong *valuep,
212 				     enum pci_size_t size)
213 {
214 	struct pcie_dw_mvebu *pcie = dev_get_priv(bus);
215 	uintptr_t va_address;
216 	ulong value;
217 
218 	debug("PCIE CFG read:  (b,d,f)=(%2d,%2d,%2d) ",
219 	      PCI_BUS(bdf), PCI_DEV(bdf), PCI_FUNC(bdf));
220 
221 	if (!pcie_dw_addr_valid(bdf, pcie->first_busno)) {
222 		debug("- out of range\n");
223 		*valuep = pci_get_ff(size);
224 		return 0;
225 	}
226 
227 	va_address = set_cfg_address(pcie, bdf, offset);
228 
229 	value = readl(va_address);
230 
231 	debug("(addr,val)=(0x%04x, 0x%08lx)\n", offset, value);
232 	*valuep = pci_conv_32_to_size(value, offset, size);
233 
234 	return 0;
235 }
236 
237 /**
238  * pcie_dw_mvebu_write_config() - Write to configuration space
239  *
240  * @bus: Pointer to the PCI bus
241  * @bdf: Identifies the PCIe device to access
242  * @offset: The offset into the device's configuration space
243  * @value: The value to write
244  * @size: Indicates the size of access to perform
245  *
246  * Write the value @value of size @size from offset @offset within the
247  * configuration space of the device identified by the bus, device & function
248  * numbers in @bdf on the PCI bus @bus.
249  *
250  * Return: 0 on success
251  */
252 static int pcie_dw_mvebu_write_config(struct udevice *bus, pci_dev_t bdf,
253 				      uint offset, ulong value,
254 				      enum pci_size_t size)
255 {
256 	struct pcie_dw_mvebu *pcie = dev_get_priv(bus);
257 	uintptr_t va_address;
258 	ulong old;
259 
260 	debug("PCIE CFG write: (b,d,f)=(%2d,%2d,%2d) ",
261 	      PCI_BUS(bdf), PCI_DEV(bdf), PCI_FUNC(bdf));
262 	debug("(addr,val)=(0x%04x, 0x%08lx)\n", offset, value);
263 
264 	if (!pcie_dw_addr_valid(bdf, pcie->first_busno)) {
265 		debug("- out of range\n");
266 		return 0;
267 	}
268 
269 	va_address = set_cfg_address(pcie, bdf, offset);
270 
271 	old = readl(va_address);
272 	value = pci_conv_size_to_32(old, value, offset, size);
273 	writel(value, va_address);
274 
275 	return 0;
276 }
277 
278 /**
279  * pcie_dw_configure() - Configure link capabilities and speed
280  *
281  * @regs_base: A pointer to the PCIe controller registers
282  * @cap_speed: The capabilities and speed to configure
283  *
284  * Configure the link capabilities and speed in the PCIe root complex.
285  */
286 static void pcie_dw_configure(const void *regs_base, u32 cap_speed)
287 {
288 	/*
289 	 * TODO (shadi@marvell.com, sr@denx.de):
290 	 * Need to read the serdes speed from the dts and according to it
291 	 * configure the PCIe gen
292 	 */
293 
294 	/* Set link to GEN 3 */
295 	clrsetbits_le32(regs_base + PCIE_LINK_CTL_2,
296 			TARGET_LINK_SPEED_MASK, cap_speed);
297 	clrsetbits_le32(regs_base + PCIE_LINK_CAPABILITY,
298 			TARGET_LINK_SPEED_MASK, cap_speed);
299 	setbits_le32(regs_base + PCIE_GEN3_EQU_CTRL, GEN3_EQU_EVAL_2MS_DISABLE);
300 }
301 
302 /**
303  * is_link_up() - Return the link state
304  *
305  * @regs_base: A pointer to the PCIe controller registers
306  *
307  * Return: 1 (true) for active line and 0 (false) for no link
308  */
309 static int is_link_up(const void *regs_base)
310 {
311 	u32 mask = PCIE_GLB_STS_RDLH_LINK_UP | PCIE_GLB_STS_PHY_LINK_UP;
312 	u32 reg;
313 
314 	reg = readl(regs_base + PCIE_GLOBAL_STATUS);
315 	if ((reg & mask) == mask)
316 		return 1;
317 
318 	return 0;
319 }
320 
321 /**
322  * wait_link_up() - Wait for the link to come up
323  *
324  * @regs_base: A pointer to the PCIe controller registers
325  *
326  * Return: 1 (true) for active line and 0 (false) for no link (timeout)
327  */
328 static int wait_link_up(const void *regs_base)
329 {
330 	unsigned long timeout;
331 
332 	timeout = get_timer(0) + PCIE_LINK_UP_TIMEOUT_MS;
333 	while (!is_link_up(regs_base)) {
334 		if (get_timer(0) > timeout)
335 			return 0;
336 	};
337 
338 	return 1;
339 }
340 
341 /**
342  * pcie_dw_mvebu_pcie_link_up() - Configure the PCIe root port
343  *
344  * @regs_base: A pointer to the PCIe controller registers
345  * @cap_speed: The capabilities and speed to configure
346  *
347  * Configure the PCIe controller root complex depending on the
348  * requested link capabilities and speed.
349  *
350  * Return: 1 (true) for active line and 0 (false) for no link
351  */
352 static int pcie_dw_mvebu_pcie_link_up(const void *regs_base, u32 cap_speed)
353 {
354 	if (!is_link_up(regs_base)) {
355 		/* Disable LTSSM state machine to enable configuration */
356 		clrbits_le32(regs_base + PCIE_GLOBAL_CONTROL,
357 			     PCIE_APP_LTSSM_EN);
358 	}
359 
360 	clrsetbits_le32(regs_base + PCIE_GLOBAL_CONTROL,
361 			PCIE_DEVICE_TYPE_MASK << PCIE_DEVICE_TYPE_OFFSET,
362 			PCIE_DEVICE_TYPE_RC << PCIE_DEVICE_TYPE_OFFSET);
363 
364 	/* Set the PCIe master AXI attributes */
365 	writel(ARCACHE_SHAREABLE_CACHEABLE, regs_base + PCIE_ARCACHE_TRC);
366 	writel(AWCACHE_SHAREABLE_CACHEABLE, regs_base + PCIE_AWCACHE_TRC);
367 
368 	/* DW pre link configurations */
369 	pcie_dw_configure(regs_base, cap_speed);
370 
371 	if (!is_link_up(regs_base)) {
372 		/* Configuration done. Start LTSSM */
373 		setbits_le32(regs_base + PCIE_GLOBAL_CONTROL,
374 			     PCIE_APP_LTSSM_EN);
375 	}
376 
377 	/* Check that link was established */
378 	if (!wait_link_up(regs_base))
379 		return 0;
380 
381 	/*
382 	 * Link can be established in Gen 1. still need to wait
383 	 * till MAC nagaotiation is completed
384 	 */
385 	udelay(100);
386 
387 	return 1;
388 }
389 
390 /**
391  * pcie_dw_regions_setup() - iATU region setup
392  *
393  * @pcie: Pointer to the PCI controller state
394  *
395  * Configure the iATU regions in the PCIe controller for outbound access.
396  */
397 static void pcie_dw_regions_setup(struct pcie_dw_mvebu *pcie)
398 {
399 	/*
400 	 * Region #0 is used for Outbound CFG space access.
401 	 * Direction = Outbound
402 	 * Region Index = 0
403 	 */
404 	writel(0, pcie->ctrl_base + PCIE_ATU_VIEWPORT);
405 
406 	writel((u32)(uintptr_t)pcie->cfg_base, pcie->ctrl_base
407 	       + PCIE_ATU_LOWER_BASE);
408 	writel(0, pcie->ctrl_base + PCIE_ATU_UPPER_BASE);
409 	writel((u32)(uintptr_t)pcie->cfg_base + pcie->cfg_size,
410 	       pcie->ctrl_base + PCIE_ATU_LIMIT);
411 
412 	writel(0, pcie->ctrl_base + PCIE_ATU_LOWER_TARGET);
413 	writel(0, pcie->ctrl_base + PCIE_ATU_UPPER_TARGET);
414 	writel(PCIE_ATU_TYPE_CFG0, pcie->ctrl_base + PCIE_ATU_CR1);
415 	writel(PCIE_ATU_ENABLE, pcie->ctrl_base + PCIE_ATU_CR2);
416 }
417 
418 /**
419  * pcie_dw_set_host_bars() - Configure the host BARs
420  *
421  * @regs_base: A pointer to the PCIe controller registers
422  *
423  * Configure the host BARs of the PCIe controller root port so that
424  * PCI(e) devices may access the system memory.
425  */
426 static void pcie_dw_set_host_bars(const void *regs_base)
427 {
428 	u32 size = gd->ram_size;
429 	u64 max_size;
430 	u32 reg;
431 	u32 bar0;
432 
433 	/* Verify the maximal BAR size */
434 	reg = readl(regs_base + RESIZABLE_BAR_CAP);
435 	max_size = 1ULL << (5 + (reg + (1 << 4)));
436 
437 	if (size > max_size) {
438 		size = max_size;
439 		printf("Warning: PCIe BARs can't map all DRAM space\n");
440 	}
441 
442 	/* Set the BAR base and size towards DDR */
443 	bar0 = CONFIG_SYS_SDRAM_BASE & ~0xf;
444 	bar0 |= PCI_BASE_ADDRESS_MEM_TYPE_32;
445 	writel(CONFIG_SYS_SDRAM_BASE, regs_base + PCIE_CONFIG_BAR0);
446 
447 	reg = ((size >> 20) - 1) << 12;
448 	writel(size, regs_base + RESIZABLE_BAR_CTL0);
449 }
450 
451 /**
452  * pcie_dw_mvebu_probe() - Probe the PCIe bus for active link
453  *
454  * @dev: A pointer to the device being operated on
455  *
456  * Probe for an active link on the PCIe bus and configure the controller
457  * to enable this port.
458  *
459  * Return: 0 on success, else -ENODEV
460  */
461 static int pcie_dw_mvebu_probe(struct udevice *dev)
462 {
463 	struct pcie_dw_mvebu *pcie = dev_get_priv(dev);
464 	struct udevice *ctlr = pci_get_controller(dev);
465 	struct pci_controller *hose = dev_get_uclass_priv(ctlr);
466 #ifdef CONFIG_DM_GPIO
467 	struct gpio_desc reset_gpio;
468 
469 	gpio_request_by_name(dev, "marvell,reset-gpio", 0, &reset_gpio,
470 			     GPIOD_IS_OUT);
471 	/*
472 	 * Issue reset to add-in card trough the dedicated GPIO.
473 	 * Some boards are connecting the card reset pin to common system
474 	 * reset wire and others are using separate GPIO port.
475 	 * In the last case we have to release a reset of the addon card
476 	 * using this GPIO.
477 	 */
478 	if (dm_gpio_is_valid(&reset_gpio)) {
479 		dm_gpio_set_value(&reset_gpio, 1);
480 		mdelay(200);
481 	}
482 #else
483 	debug("PCIE Reset on GPIO support is missing\n");
484 #endif /* CONFIG_DM_GPIO */
485 
486 	pcie->first_busno = dev->seq;
487 
488 	/* Don't register host if link is down */
489 	if (!pcie_dw_mvebu_pcie_link_up(pcie->ctrl_base, LINK_SPEED_GEN_3)) {
490 		printf("PCIE-%d: Link down\n", dev->seq);
491 	} else {
492 		printf("PCIE-%d: Link up (Gen%d-x%d, Bus%d)\n", dev->seq,
493 		       pcie_dw_get_link_speed(pcie->ctrl_base),
494 		       pcie_dw_get_link_width(pcie->ctrl_base),
495 		       hose->first_busno);
496 	}
497 
498 	pcie_dw_regions_setup(pcie);
499 
500 	/* Set the CLASS_REV of RC CFG header to PCI_CLASS_BRIDGE_PCI */
501 	clrsetbits_le32(pcie->ctrl_base + PCI_CLASS_REVISION,
502 			0xffff << 16, PCI_CLASS_BRIDGE_PCI << 16);
503 
504 	pcie_dw_set_host_bars(pcie->ctrl_base);
505 
506 	return 0;
507 }
508 
509 /**
510  * pcie_dw_mvebu_ofdata_to_platdata() - Translate from DT to device state
511  *
512  * @dev: A pointer to the device being operated on
513  *
514  * Translate relevant data from the device tree pertaining to device @dev into
515  * state that the driver will later make use of. This state is stored in the
516  * device's private data structure.
517  *
518  * Return: 0 on success, else -EINVAL
519  */
520 static int pcie_dw_mvebu_ofdata_to_platdata(struct udevice *dev)
521 {
522 	struct pcie_dw_mvebu *pcie = dev_get_priv(dev);
523 
524 	/* Get the controller base address */
525 	pcie->ctrl_base = (void *)devfdt_get_addr_index(dev, 0);
526 	if ((fdt_addr_t)pcie->ctrl_base == FDT_ADDR_T_NONE)
527 		return -EINVAL;
528 
529 	/* Get the config space base address and size */
530 	pcie->cfg_base = (void *)devfdt_get_addr_size_index(dev, 1,
531 							 &pcie->cfg_size);
532 	if ((fdt_addr_t)pcie->cfg_base == FDT_ADDR_T_NONE)
533 		return -EINVAL;
534 
535 	return 0;
536 }
537 
538 static const struct dm_pci_ops pcie_dw_mvebu_ops = {
539 	.read_config	= pcie_dw_mvebu_read_config,
540 	.write_config	= pcie_dw_mvebu_write_config,
541 };
542 
543 static const struct udevice_id pcie_dw_mvebu_ids[] = {
544 	{ .compatible = "marvell,armada8k-pcie" },
545 	{ }
546 };
547 
548 U_BOOT_DRIVER(pcie_dw_mvebu) = {
549 	.name			= "pcie_dw_mvebu",
550 	.id			= UCLASS_PCI,
551 	.of_match		= pcie_dw_mvebu_ids,
552 	.ops			= &pcie_dw_mvebu_ops,
553 	.ofdata_to_platdata	= pcie_dw_mvebu_ofdata_to_platdata,
554 	.probe			= pcie_dw_mvebu_probe,
555 	.priv_auto_alloc_size	= sizeof(struct pcie_dw_mvebu),
556 };
557