blob: 1568f20c1a060bfd28e633088acc1644fa51b571 [file] [log] [blame]
Marek Vasute9be4292013-12-14 05:55:28 +01001/*
2 * Freescale i.MX6 PCI Express Root-Complex driver
3 *
4 * Copyright (C) 2013 Marek Vasut <marex@denx.de>
5 *
6 * Based on upstream Linux kernel driver:
7 * pci-imx6.c: Sean Cross <xobs@kosagi.com>
8 * pcie-designware.c: Jingoo Han <jg1.han@samsung.com>
9 *
10 * SPDX-License-Identifier: GPL-2.0
11 */
12
13#include <common.h>
14#include <pci.h>
15#include <asm/arch/clock.h>
16#include <asm/arch/iomux.h>
17#include <asm/arch/crm_regs.h>
Marek Vasutbb019562014-02-03 21:46:22 +010018#include <asm/gpio.h>
Marek Vasute9be4292013-12-14 05:55:28 +010019#include <asm/io.h>
Alexey Brodkin1ace4022014-02-26 17:47:58 +040020#include <linux/sizes.h>
Marek Vasute9be4292013-12-14 05:55:28 +010021#include <errno.h>
22
23#define PCI_ACCESS_READ 0
24#define PCI_ACCESS_WRITE 1
25
Fabio Estevam1b8ad742014-08-25 14:26:45 -030026#ifdef CONFIG_MX6SX
27#define MX6_DBI_ADDR 0x08ffc000
28#define MX6_IO_ADDR 0x08000000
29#define MX6_MEM_ADDR 0x08100000
30#define MX6_ROOT_ADDR 0x08f00000
31#else
Marek Vasute9be4292013-12-14 05:55:28 +010032#define MX6_DBI_ADDR 0x01ffc000
Marek Vasute9be4292013-12-14 05:55:28 +010033#define MX6_IO_ADDR 0x01000000
Marek Vasute9be4292013-12-14 05:55:28 +010034#define MX6_MEM_ADDR 0x01100000
Marek Vasute9be4292013-12-14 05:55:28 +010035#define MX6_ROOT_ADDR 0x01f00000
Fabio Estevam1b8ad742014-08-25 14:26:45 -030036#endif
37#define MX6_DBI_SIZE 0x4000
38#define MX6_IO_SIZE 0x100000
39#define MX6_MEM_SIZE 0xe00000
Marek Vasute9be4292013-12-14 05:55:28 +010040#define MX6_ROOT_SIZE 0xfc000
41
42/* PCIe Port Logic registers (memory-mapped) */
43#define PL_OFFSET 0x700
44#define PCIE_PHY_DEBUG_R0 (PL_OFFSET + 0x28)
45#define PCIE_PHY_DEBUG_R1 (PL_OFFSET + 0x2c)
46#define PCIE_PHY_DEBUG_R1_LINK_UP (1 << 4)
47#define PCIE_PHY_DEBUG_R1_LINK_IN_TRAINING (1 << 29)
48
49#define PCIE_PHY_CTRL (PL_OFFSET + 0x114)
50#define PCIE_PHY_CTRL_DATA_LOC 0
51#define PCIE_PHY_CTRL_CAP_ADR_LOC 16
52#define PCIE_PHY_CTRL_CAP_DAT_LOC 17
53#define PCIE_PHY_CTRL_WR_LOC 18
54#define PCIE_PHY_CTRL_RD_LOC 19
55
56#define PCIE_PHY_STAT (PL_OFFSET + 0x110)
57#define PCIE_PHY_STAT_DATA_LOC 0
58#define PCIE_PHY_STAT_ACK_LOC 16
59
60/* PHY registers (not memory-mapped) */
61#define PCIE_PHY_RX_ASIC_OUT 0x100D
62
63#define PHY_RX_OVRD_IN_LO 0x1005
64#define PHY_RX_OVRD_IN_LO_RX_DATA_EN (1 << 5)
65#define PHY_RX_OVRD_IN_LO_RX_PLL_EN (1 << 3)
66
Fabio Estevam1b8ad742014-08-25 14:26:45 -030067#define PCIE_PHY_PUP_REQ (1 << 7)
68
Marek Vasute9be4292013-12-14 05:55:28 +010069/* iATU registers */
70#define PCIE_ATU_VIEWPORT 0x900
71#define PCIE_ATU_REGION_INBOUND (0x1 << 31)
72#define PCIE_ATU_REGION_OUTBOUND (0x0 << 31)
73#define PCIE_ATU_REGION_INDEX1 (0x1 << 0)
74#define PCIE_ATU_REGION_INDEX0 (0x0 << 0)
75#define PCIE_ATU_CR1 0x904
76#define PCIE_ATU_TYPE_MEM (0x0 << 0)
77#define PCIE_ATU_TYPE_IO (0x2 << 0)
78#define PCIE_ATU_TYPE_CFG0 (0x4 << 0)
79#define PCIE_ATU_TYPE_CFG1 (0x5 << 0)
80#define PCIE_ATU_CR2 0x908
81#define PCIE_ATU_ENABLE (0x1 << 31)
82#define PCIE_ATU_BAR_MODE_ENABLE (0x1 << 30)
83#define PCIE_ATU_LOWER_BASE 0x90C
84#define PCIE_ATU_UPPER_BASE 0x910
85#define PCIE_ATU_LIMIT 0x914
86#define PCIE_ATU_LOWER_TARGET 0x918
87#define PCIE_ATU_BUS(x) (((x) & 0xff) << 24)
88#define PCIE_ATU_DEV(x) (((x) & 0x1f) << 19)
89#define PCIE_ATU_FUNC(x) (((x) & 0x7) << 16)
90#define PCIE_ATU_UPPER_TARGET 0x91C
91
92/*
93 * PHY access functions
94 */
95static int pcie_phy_poll_ack(void __iomem *dbi_base, int exp_val)
96{
97 u32 val;
98 u32 max_iterations = 10;
99 u32 wait_counter = 0;
100
101 do {
102 val = readl(dbi_base + PCIE_PHY_STAT);
103 val = (val >> PCIE_PHY_STAT_ACK_LOC) & 0x1;
104 wait_counter++;
105
106 if (val == exp_val)
107 return 0;
108
109 udelay(1);
110 } while (wait_counter < max_iterations);
111
112 return -ETIMEDOUT;
113}
114
115static int pcie_phy_wait_ack(void __iomem *dbi_base, int addr)
116{
117 u32 val;
118 int ret;
119
120 val = addr << PCIE_PHY_CTRL_DATA_LOC;
121 writel(val, dbi_base + PCIE_PHY_CTRL);
122
123 val |= (0x1 << PCIE_PHY_CTRL_CAP_ADR_LOC);
124 writel(val, dbi_base + PCIE_PHY_CTRL);
125
126 ret = pcie_phy_poll_ack(dbi_base, 1);
127 if (ret)
128 return ret;
129
130 val = addr << PCIE_PHY_CTRL_DATA_LOC;
131 writel(val, dbi_base + PCIE_PHY_CTRL);
132
133 ret = pcie_phy_poll_ack(dbi_base, 0);
134 if (ret)
135 return ret;
136
137 return 0;
138}
139
140/* Read from the 16-bit PCIe PHY control registers (not memory-mapped) */
141static int pcie_phy_read(void __iomem *dbi_base, int addr , int *data)
142{
143 u32 val, phy_ctl;
144 int ret;
145
146 ret = pcie_phy_wait_ack(dbi_base, addr);
147 if (ret)
148 return ret;
149
150 /* assert Read signal */
151 phy_ctl = 0x1 << PCIE_PHY_CTRL_RD_LOC;
152 writel(phy_ctl, dbi_base + PCIE_PHY_CTRL);
153
154 ret = pcie_phy_poll_ack(dbi_base, 1);
155 if (ret)
156 return ret;
157
158 val = readl(dbi_base + PCIE_PHY_STAT);
159 *data = val & 0xffff;
160
161 /* deassert Read signal */
162 writel(0x00, dbi_base + PCIE_PHY_CTRL);
163
164 ret = pcie_phy_poll_ack(dbi_base, 0);
165 if (ret)
166 return ret;
167
168 return 0;
169}
170
171static int pcie_phy_write(void __iomem *dbi_base, int addr, int data)
172{
173 u32 var;
174 int ret;
175
176 /* write addr */
177 /* cap addr */
178 ret = pcie_phy_wait_ack(dbi_base, addr);
179 if (ret)
180 return ret;
181
182 var = data << PCIE_PHY_CTRL_DATA_LOC;
183 writel(var, dbi_base + PCIE_PHY_CTRL);
184
185 /* capture data */
186 var |= (0x1 << PCIE_PHY_CTRL_CAP_DAT_LOC);
187 writel(var, dbi_base + PCIE_PHY_CTRL);
188
189 ret = pcie_phy_poll_ack(dbi_base, 1);
190 if (ret)
191 return ret;
192
193 /* deassert cap data */
194 var = data << PCIE_PHY_CTRL_DATA_LOC;
195 writel(var, dbi_base + PCIE_PHY_CTRL);
196
197 /* wait for ack de-assertion */
198 ret = pcie_phy_poll_ack(dbi_base, 0);
199 if (ret)
200 return ret;
201
202 /* assert wr signal */
203 var = 0x1 << PCIE_PHY_CTRL_WR_LOC;
204 writel(var, dbi_base + PCIE_PHY_CTRL);
205
206 /* wait for ack */
207 ret = pcie_phy_poll_ack(dbi_base, 1);
208 if (ret)
209 return ret;
210
211 /* deassert wr signal */
212 var = data << PCIE_PHY_CTRL_DATA_LOC;
213 writel(var, dbi_base + PCIE_PHY_CTRL);
214
215 /* wait for ack de-assertion */
216 ret = pcie_phy_poll_ack(dbi_base, 0);
217 if (ret)
218 return ret;
219
220 writel(0x0, dbi_base + PCIE_PHY_CTRL);
221
222 return 0;
223}
224
225static int imx6_pcie_link_up(void)
226{
227 u32 rc, ltssm;
228 int rx_valid, temp;
229
230 /* link is debug bit 36, debug register 1 starts at bit 32 */
231 rc = readl(MX6_DBI_ADDR + PCIE_PHY_DEBUG_R1);
232 if ((rc & PCIE_PHY_DEBUG_R1_LINK_UP) &&
233 !(rc & PCIE_PHY_DEBUG_R1_LINK_IN_TRAINING))
234 return -EAGAIN;
235
236 /*
237 * From L0, initiate MAC entry to gen2 if EP/RC supports gen2.
238 * Wait 2ms (LTSSM timeout is 24ms, PHY lock is ~5us in gen2).
239 * If (MAC/LTSSM.state == Recovery.RcvrLock)
240 * && (PHY/rx_valid==0) then pulse PHY/rx_reset. Transition
241 * to gen2 is stuck
242 */
243 pcie_phy_read((void *)MX6_DBI_ADDR, PCIE_PHY_RX_ASIC_OUT, &rx_valid);
244 ltssm = readl(MX6_DBI_ADDR + PCIE_PHY_DEBUG_R0) & 0x3F;
245
246 if (rx_valid & 0x01)
247 return 0;
248
249 if (ltssm != 0x0d)
250 return 0;
251
252 printf("transition to gen2 is stuck, reset PHY!\n");
253
254 pcie_phy_read((void *)MX6_DBI_ADDR, PHY_RX_OVRD_IN_LO, &temp);
255 temp |= (PHY_RX_OVRD_IN_LO_RX_DATA_EN | PHY_RX_OVRD_IN_LO_RX_PLL_EN);
256 pcie_phy_write((void *)MX6_DBI_ADDR, PHY_RX_OVRD_IN_LO, temp);
257
258 udelay(3000);
259
260 pcie_phy_read((void *)MX6_DBI_ADDR, PHY_RX_OVRD_IN_LO, &temp);
261 temp &= ~(PHY_RX_OVRD_IN_LO_RX_DATA_EN | PHY_RX_OVRD_IN_LO_RX_PLL_EN);
262 pcie_phy_write((void *)MX6_DBI_ADDR, PHY_RX_OVRD_IN_LO, temp);
263
264 return 0;
265}
266
267/*
268 * iATU region setup
269 */
270static int imx_pcie_regions_setup(void)
271{
272 /*
273 * i.MX6 defines 16MB in the AXI address map for PCIe.
274 *
275 * That address space excepted the pcie registers is
276 * split and defined into different regions by iATU,
277 * with sizes and offsets as follows:
278 *
279 * 0x0100_0000 --- 0x010F_FFFF 1MB IORESOURCE_IO
280 * 0x0110_0000 --- 0x01EF_FFFF 14MB IORESOURCE_MEM
281 * 0x01F0_0000 --- 0x01FF_FFFF 1MB Cfg + Registers
282 */
283
284 /* CMD reg:I/O space, MEM space, and Bus Master Enable */
285 setbits_le32(MX6_DBI_ADDR | PCI_COMMAND,
286 PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
287
288 /* Set the CLASS_REV of RC CFG header to PCI_CLASS_BRIDGE_PCI */
289 setbits_le32(MX6_DBI_ADDR + PCI_CLASS_REVISION,
290 PCI_CLASS_BRIDGE_PCI << 16);
291
292 /* Region #0 is used for Outbound CFG space access. */
293 writel(0, MX6_DBI_ADDR + PCIE_ATU_VIEWPORT);
294
295 writel(MX6_ROOT_ADDR, MX6_DBI_ADDR + PCIE_ATU_LOWER_BASE);
296 writel(0, MX6_DBI_ADDR + PCIE_ATU_UPPER_BASE);
297 writel(MX6_ROOT_ADDR + MX6_ROOT_SIZE, MX6_DBI_ADDR + PCIE_ATU_LIMIT);
298
299 writel(0, MX6_DBI_ADDR + PCIE_ATU_LOWER_TARGET);
300 writel(0, MX6_DBI_ADDR + PCIE_ATU_UPPER_TARGET);
301 writel(PCIE_ATU_TYPE_CFG0, MX6_DBI_ADDR + PCIE_ATU_CR1);
302 writel(PCIE_ATU_ENABLE, MX6_DBI_ADDR + PCIE_ATU_CR2);
303
304 return 0;
305}
306
307/*
308 * PCI Express accessors
309 */
310static uint32_t get_bus_address(pci_dev_t d, int where)
311{
312 uint32_t va_address;
313
314 /* Reconfigure Region #0 */
315 writel(0, MX6_DBI_ADDR + PCIE_ATU_VIEWPORT);
316
317 if (PCI_BUS(d) < 2)
318 writel(PCIE_ATU_TYPE_CFG0, MX6_DBI_ADDR + PCIE_ATU_CR1);
319 else
320 writel(PCIE_ATU_TYPE_CFG1, MX6_DBI_ADDR + PCIE_ATU_CR1);
321
322 if (PCI_BUS(d) == 0) {
323 va_address = MX6_DBI_ADDR;
324 } else {
325 writel(d << 8, MX6_DBI_ADDR + PCIE_ATU_LOWER_TARGET);
326 va_address = MX6_IO_ADDR + SZ_16M - SZ_1M;
327 }
328
329 va_address += (where & ~0x3);
330
331 return va_address;
332}
333
334static int imx_pcie_addr_valid(pci_dev_t d)
335{
336 if ((PCI_BUS(d) == 0) && (PCI_DEV(d) > 1))
337 return -EINVAL;
338 if ((PCI_BUS(d) == 1) && (PCI_DEV(d) > 0))
339 return -EINVAL;
340 return 0;
341}
342
343/*
344 * Replace the original ARM DABT handler with a simple jump-back one.
345 *
346 * The problem here is that if we have a PCIe bridge attached to this PCIe
347 * controller, but no PCIe device is connected to the bridges' downstream
348 * port, the attempt to read/write from/to the config space will produce
349 * a DABT. This is a behavior of the controller and can not be disabled
350 * unfortuatelly.
351 *
352 * To work around the problem, we backup the current DABT handler address
353 * and replace it with our own DABT handler, which only bounces right back
354 * into the code.
355 */
356static void imx_pcie_fix_dabt_handler(bool set)
357{
358 extern uint32_t *_data_abort;
359 uint32_t *data_abort_addr = (uint32_t *)&_data_abort;
360
361 static const uint32_t data_abort_bounce_handler = 0xe25ef004;
362 uint32_t data_abort_bounce_addr = (uint32_t)&data_abort_bounce_handler;
363
364 static uint32_t data_abort_backup;
365
366 if (set) {
367 data_abort_backup = *data_abort_addr;
368 *data_abort_addr = data_abort_bounce_addr;
369 } else {
370 *data_abort_addr = data_abort_backup;
371 }
372}
373
374static int imx_pcie_read_config(struct pci_controller *hose, pci_dev_t d,
375 int where, u32 *val)
376{
377 uint32_t va_address;
378 int ret;
379
380 ret = imx_pcie_addr_valid(d);
381 if (ret) {
382 *val = 0xffffffff;
383 return ret;
384 }
385
386 va_address = get_bus_address(d, where);
387
388 /*
389 * Read the PCIe config space. We must replace the DABT handler
390 * here in case we got data abort from the PCIe controller, see
391 * imx_pcie_fix_dabt_handler() description. Note that writing the
392 * "val" with valid value is also imperative here as in case we
393 * did got DABT, the val would contain random value.
394 */
395 imx_pcie_fix_dabt_handler(true);
396 writel(0xffffffff, val);
397 *val = readl(va_address);
398 imx_pcie_fix_dabt_handler(false);
399
400 return 0;
401}
402
403static int imx_pcie_write_config(struct pci_controller *hose, pci_dev_t d,
404 int where, u32 val)
405{
406 uint32_t va_address = 0;
407 int ret;
408
409 ret = imx_pcie_addr_valid(d);
410 if (ret)
411 return ret;
412
413 va_address = get_bus_address(d, where);
414
415 /*
416 * Write the PCIe config space. We must replace the DABT handler
417 * here in case we got data abort from the PCIe controller, see
418 * imx_pcie_fix_dabt_handler() description.
419 */
420 imx_pcie_fix_dabt_handler(true);
421 writel(val, va_address);
422 imx_pcie_fix_dabt_handler(false);
423
424 return 0;
425}
426
427/*
428 * Initial bus setup
429 */
430static int imx6_pcie_assert_core_reset(void)
431{
432 struct iomuxc *iomuxc_regs = (struct iomuxc *)IOMUXC_BASE_ADDR;
Fabio Estevam1b8ad742014-08-25 14:26:45 -0300433#if defined(CONFIG_MX6SX)
434 struct gpc *gpc_regs = (struct gpc *)GPC_BASE_ADDR;
Marek Vasute9be4292013-12-14 05:55:28 +0100435
Fabio Estevam1b8ad742014-08-25 14:26:45 -0300436 /* SSP_EN is not used on MX6SX anymore */
437 setbits_le32(&iomuxc_regs->gpr[12], IOMUXC_GPR12_TEST_POWERDOWN);
438 /* Force PCIe PHY reset */
439 setbits_le32(&iomuxc_regs->gpr[5], IOMUXC_GPR5_PCIE_BTNRST);
440 /* Power up PCIe PHY */
441 setbits_le32(&gpc_regs->cntr, PCIE_PHY_PUP_REQ);
442#else
Marek Vasute9be4292013-12-14 05:55:28 +0100443 setbits_le32(&iomuxc_regs->gpr[1], IOMUXC_GPR1_TEST_POWERDOWN);
444 clrbits_le32(&iomuxc_regs->gpr[1], IOMUXC_GPR1_REF_SSP_EN);
Fabio Estevam1b8ad742014-08-25 14:26:45 -0300445#endif
Marek Vasute9be4292013-12-14 05:55:28 +0100446
447 return 0;
448}
449
450static int imx6_pcie_init_phy(void)
451{
452 struct iomuxc *iomuxc_regs = (struct iomuxc *)IOMUXC_BASE_ADDR;
453
454 clrbits_le32(&iomuxc_regs->gpr[12], IOMUXC_GPR12_APPS_LTSSM_ENABLE);
455
456 clrsetbits_le32(&iomuxc_regs->gpr[12],
457 IOMUXC_GPR12_DEVICE_TYPE_MASK,
458 IOMUXC_GPR12_DEVICE_TYPE_RC);
459 clrsetbits_le32(&iomuxc_regs->gpr[12],
460 IOMUXC_GPR12_LOS_LEVEL_MASK,
461 IOMUXC_GPR12_LOS_LEVEL_9);
462
Fabio Estevam1b8ad742014-08-25 14:26:45 -0300463#ifdef CONFIG_MX6SX
464 clrsetbits_le32(&iomuxc_regs->gpr[12],
465 IOMUXC_GPR12_RX_EQ_MASK,
466 IOMUXC_GPR12_RX_EQ_2);
467#endif
468
Marek Vasute9be4292013-12-14 05:55:28 +0100469 writel((0x0 << IOMUXC_GPR8_PCS_TX_DEEMPH_GEN1_OFFSET) |
470 (0x0 << IOMUXC_GPR8_PCS_TX_DEEMPH_GEN2_3P5DB_OFFSET) |
471 (20 << IOMUXC_GPR8_PCS_TX_DEEMPH_GEN2_6DB_OFFSET) |
472 (127 << IOMUXC_GPR8_PCS_TX_SWING_FULL_OFFSET) |
473 (127 << IOMUXC_GPR8_PCS_TX_SWING_LOW_OFFSET),
474 &iomuxc_regs->gpr[8]);
475
476 return 0;
477}
478
Marek Vasuta778aea2014-03-23 22:45:40 +0100479__weak int imx6_pcie_toggle_power(void)
480{
481#ifdef CONFIG_PCIE_IMX_POWER_GPIO
482 gpio_direction_output(CONFIG_PCIE_IMX_POWER_GPIO, 0);
483 mdelay(20);
484 gpio_set_value(CONFIG_PCIE_IMX_POWER_GPIO, 1);
485 mdelay(20);
486#endif
487 return 0;
488}
489
Marek Vasutbb019562014-02-03 21:46:22 +0100490__weak int imx6_pcie_toggle_reset(void)
491{
492 /*
493 * See 'PCI EXPRESS BASE SPECIFICATION, REV 3.0, SECTION 6.6.1'
494 * for detailed understanding of the PCIe CR reset logic.
495 *
496 * The PCIe #PERST reset line _MUST_ be connected, otherwise your
497 * design does not conform to the specification. You must wait at
Fabio Estevam8f6edf62015-09-10 20:45:25 -0300498 * least 20 ms after de-asserting the #PERST so the EP device can
Marek Vasutbb019562014-02-03 21:46:22 +0100499 * do self-initialisation.
500 *
501 * In case your #PERST pin is connected to a plain GPIO pin of the
502 * CPU, you can define CONFIG_PCIE_IMX_PERST_GPIO in your board's
503 * configuration file and the condition below will handle the rest
504 * of the reset toggling.
505 *
506 * In case your #PERST toggling logic is more complex, for example
507 * connected via CPLD or somesuch, you can override this function
508 * in your board file and implement reset logic as needed. You must
Fabio Estevam8f6edf62015-09-10 20:45:25 -0300509 * not forget to wait at least 20 ms after de-asserting #PERST in
Marek Vasutbb019562014-02-03 21:46:22 +0100510 * this case either though.
511 *
512 * In case your #PERST line of the PCIe EP device is not connected
513 * at all, your design is broken and you should fix your design,
514 * otherwise you will observe problems like for example the link
515 * not coming up after rebooting the system back from running Linux
516 * that uses the PCIe as well OR the PCIe link might not come up in
517 * Linux at all in the first place since it's in some non-reset
518 * state due to being previously used in U-Boot.
519 */
520#ifdef CONFIG_PCIE_IMX_PERST_GPIO
521 gpio_direction_output(CONFIG_PCIE_IMX_PERST_GPIO, 0);
522 mdelay(20);
523 gpio_set_value(CONFIG_PCIE_IMX_PERST_GPIO, 1);
524 mdelay(20);
525#else
526 puts("WARNING: Make sure the PCIe #PERST line is connected!\n");
527#endif
528 return 0;
529}
530
Marek Vasute9be4292013-12-14 05:55:28 +0100531static int imx6_pcie_deassert_core_reset(void)
532{
533 struct iomuxc *iomuxc_regs = (struct iomuxc *)IOMUXC_BASE_ADDR;
534
Marek Vasuta778aea2014-03-23 22:45:40 +0100535 imx6_pcie_toggle_power();
Marek Vasute9be4292013-12-14 05:55:28 +0100536
Marek Vasute9be4292013-12-14 05:55:28 +0100537 enable_pcie_clock();
538
539 /*
540 * Wait for the clock to settle a bit, when the clock are sourced
Fabio Estevam8f6edf62015-09-10 20:45:25 -0300541 * from the CPU, we need about 30 ms to settle.
Marek Vasute9be4292013-12-14 05:55:28 +0100542 */
Marek Vasutbb019562014-02-03 21:46:22 +0100543 mdelay(50);
Marek Vasute9be4292013-12-14 05:55:28 +0100544
Fabio Estevam1b8ad742014-08-25 14:26:45 -0300545#if defined(CONFIG_MX6SX)
546 /* SSP_EN is not used on MX6SX anymore */
547 clrbits_le32(&iomuxc_regs->gpr[12], IOMUXC_GPR12_TEST_POWERDOWN);
548 /* Clear PCIe PHY reset bit */
549 clrbits_le32(&iomuxc_regs->gpr[5], IOMUXC_GPR5_PCIE_BTNRST);
550#else
Tim Harvey5a82e1a2014-08-07 22:57:29 -0700551 /* Enable PCIe */
552 clrbits_le32(&iomuxc_regs->gpr[1], IOMUXC_GPR1_TEST_POWERDOWN);
553 setbits_le32(&iomuxc_regs->gpr[1], IOMUXC_GPR1_REF_SSP_EN);
Fabio Estevam1b8ad742014-08-25 14:26:45 -0300554#endif
Tim Harvey5a82e1a2014-08-07 22:57:29 -0700555
Marek Vasutbb019562014-02-03 21:46:22 +0100556 imx6_pcie_toggle_reset();
Marek Vasute9be4292013-12-14 05:55:28 +0100557
558 return 0;
559}
560
561static int imx_pcie_link_up(void)
562{
563 struct iomuxc *iomuxc_regs = (struct iomuxc *)IOMUXC_BASE_ADDR;
564 uint32_t tmp;
565 int count = 0;
566
567 imx6_pcie_assert_core_reset();
568 imx6_pcie_init_phy();
569 imx6_pcie_deassert_core_reset();
570
571 imx_pcie_regions_setup();
572
573 /*
574 * FIXME: Force the PCIe RC to Gen1 operation
575 * The RC must be forced into Gen1 mode before bringing the link
576 * up, otherwise no downstream devices are detected. After the
577 * link is up, a managed Gen1->Gen2 transition can be initiated.
578 */
579 tmp = readl(MX6_DBI_ADDR + 0x7c);
580 tmp &= ~0xf;
581 tmp |= 0x1;
582 writel(tmp, MX6_DBI_ADDR + 0x7c);
583
584 /* LTSSM enable, starting link. */
585 setbits_le32(&iomuxc_regs->gpr[12], IOMUXC_GPR12_APPS_LTSSM_ENABLE);
586
587 while (!imx6_pcie_link_up()) {
588 udelay(10);
589 count++;
590 if (count >= 2000) {
Tim Harvey378b02d2015-05-08 15:17:10 -0700591#ifdef CONFIG_PCI_SCAN_SHOW
592 puts("PCI: pcie phy link never came up\n");
593#endif
Marek Vasute9be4292013-12-14 05:55:28 +0100594 debug("DEBUG_R0: 0x%08x, DEBUG_R1: 0x%08x\n",
595 readl(MX6_DBI_ADDR + PCIE_PHY_DEBUG_R0),
596 readl(MX6_DBI_ADDR + PCIE_PHY_DEBUG_R1));
597 return -EINVAL;
598 }
599 }
600
601 return 0;
602}
603
604void imx_pcie_init(void)
605{
606 /* Static instance of the controller. */
607 static struct pci_controller pcc;
608 struct pci_controller *hose = &pcc;
609 int ret;
610
611 memset(&pcc, 0, sizeof(pcc));
612
613 /* PCI I/O space */
614 pci_set_region(&hose->regions[0],
615 MX6_IO_ADDR, MX6_IO_ADDR,
616 MX6_IO_SIZE, PCI_REGION_IO);
617
618 /* PCI memory space */
619 pci_set_region(&hose->regions[1],
620 MX6_MEM_ADDR, MX6_MEM_ADDR,
621 MX6_MEM_SIZE, PCI_REGION_MEM);
622
623 /* System memory space */
624 pci_set_region(&hose->regions[2],
625 MMDC0_ARB_BASE_ADDR, MMDC0_ARB_BASE_ADDR,
626 0xefffffff, PCI_REGION_MEM | PCI_REGION_SYS_MEMORY);
627
628 hose->region_count = 3;
629
630 pci_set_ops(hose,
631 pci_hose_read_config_byte_via_dword,
632 pci_hose_read_config_word_via_dword,
633 imx_pcie_read_config,
634 pci_hose_write_config_byte_via_dword,
635 pci_hose_write_config_word_via_dword,
636 imx_pcie_write_config);
637
638 /* Start the controller. */
639 ret = imx_pcie_link_up();
640
641 if (!ret) {
642 pci_register_hose(hose);
643 hose->last_busno = pci_hose_scan(hose);
644 }
645}
646
647/* Probe function. */
648void pci_init_board(void)
649{
650 imx_pcie_init();
651}