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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>
Fabio Estevamaaf87f02015-10-13 11:01:27 -030022#include <asm/arch/sys_proto.h>
Marek Vasute9be4292013-12-14 05:55:28 +010023
24#define PCI_ACCESS_READ 0
25#define PCI_ACCESS_WRITE 1
26
Fabio Estevam1b8ad742014-08-25 14:26:45 -030027#ifdef CONFIG_MX6SX
28#define MX6_DBI_ADDR 0x08ffc000
29#define MX6_IO_ADDR 0x08000000
30#define MX6_MEM_ADDR 0x08100000
31#define MX6_ROOT_ADDR 0x08f00000
32#else
Marek Vasute9be4292013-12-14 05:55:28 +010033#define MX6_DBI_ADDR 0x01ffc000
Marek Vasute9be4292013-12-14 05:55:28 +010034#define MX6_IO_ADDR 0x01000000
Marek Vasute9be4292013-12-14 05:55:28 +010035#define MX6_MEM_ADDR 0x01100000
Marek Vasute9be4292013-12-14 05:55:28 +010036#define MX6_ROOT_ADDR 0x01f00000
Fabio Estevam1b8ad742014-08-25 14:26:45 -030037#endif
38#define MX6_DBI_SIZE 0x4000
39#define MX6_IO_SIZE 0x100000
40#define MX6_MEM_SIZE 0xe00000
Marek Vasute9be4292013-12-14 05:55:28 +010041#define MX6_ROOT_SIZE 0xfc000
42
43/* PCIe Port Logic registers (memory-mapped) */
44#define PL_OFFSET 0x700
45#define PCIE_PHY_DEBUG_R0 (PL_OFFSET + 0x28)
46#define PCIE_PHY_DEBUG_R1 (PL_OFFSET + 0x2c)
47#define PCIE_PHY_DEBUG_R1_LINK_UP (1 << 4)
48#define PCIE_PHY_DEBUG_R1_LINK_IN_TRAINING (1 << 29)
49
50#define PCIE_PHY_CTRL (PL_OFFSET + 0x114)
51#define PCIE_PHY_CTRL_DATA_LOC 0
52#define PCIE_PHY_CTRL_CAP_ADR_LOC 16
53#define PCIE_PHY_CTRL_CAP_DAT_LOC 17
54#define PCIE_PHY_CTRL_WR_LOC 18
55#define PCIE_PHY_CTRL_RD_LOC 19
56
57#define PCIE_PHY_STAT (PL_OFFSET + 0x110)
58#define PCIE_PHY_STAT_DATA_LOC 0
59#define PCIE_PHY_STAT_ACK_LOC 16
60
61/* PHY registers (not memory-mapped) */
62#define PCIE_PHY_RX_ASIC_OUT 0x100D
63
64#define PHY_RX_OVRD_IN_LO 0x1005
65#define PHY_RX_OVRD_IN_LO_RX_DATA_EN (1 << 5)
66#define PHY_RX_OVRD_IN_LO_RX_PLL_EN (1 << 3)
67
Fabio Estevam1b8ad742014-08-25 14:26:45 -030068#define PCIE_PHY_PUP_REQ (1 << 7)
69
Marek Vasute9be4292013-12-14 05:55:28 +010070/* iATU registers */
71#define PCIE_ATU_VIEWPORT 0x900
72#define PCIE_ATU_REGION_INBOUND (0x1 << 31)
73#define PCIE_ATU_REGION_OUTBOUND (0x0 << 31)
74#define PCIE_ATU_REGION_INDEX1 (0x1 << 0)
75#define PCIE_ATU_REGION_INDEX0 (0x0 << 0)
76#define PCIE_ATU_CR1 0x904
77#define PCIE_ATU_TYPE_MEM (0x0 << 0)
78#define PCIE_ATU_TYPE_IO (0x2 << 0)
79#define PCIE_ATU_TYPE_CFG0 (0x4 << 0)
80#define PCIE_ATU_TYPE_CFG1 (0x5 << 0)
81#define PCIE_ATU_CR2 0x908
82#define PCIE_ATU_ENABLE (0x1 << 31)
83#define PCIE_ATU_BAR_MODE_ENABLE (0x1 << 30)
84#define PCIE_ATU_LOWER_BASE 0x90C
85#define PCIE_ATU_UPPER_BASE 0x910
86#define PCIE_ATU_LIMIT 0x914
87#define PCIE_ATU_LOWER_TARGET 0x918
88#define PCIE_ATU_BUS(x) (((x) & 0xff) << 24)
89#define PCIE_ATU_DEV(x) (((x) & 0x1f) << 19)
90#define PCIE_ATU_FUNC(x) (((x) & 0x7) << 16)
91#define PCIE_ATU_UPPER_TARGET 0x91C
92
93/*
94 * PHY access functions
95 */
96static int pcie_phy_poll_ack(void __iomem *dbi_base, int exp_val)
97{
98 u32 val;
99 u32 max_iterations = 10;
100 u32 wait_counter = 0;
101
102 do {
103 val = readl(dbi_base + PCIE_PHY_STAT);
104 val = (val >> PCIE_PHY_STAT_ACK_LOC) & 0x1;
105 wait_counter++;
106
107 if (val == exp_val)
108 return 0;
109
110 udelay(1);
111 } while (wait_counter < max_iterations);
112
113 return -ETIMEDOUT;
114}
115
116static int pcie_phy_wait_ack(void __iomem *dbi_base, int addr)
117{
118 u32 val;
119 int ret;
120
121 val = addr << PCIE_PHY_CTRL_DATA_LOC;
122 writel(val, dbi_base + PCIE_PHY_CTRL);
123
124 val |= (0x1 << PCIE_PHY_CTRL_CAP_ADR_LOC);
125 writel(val, dbi_base + PCIE_PHY_CTRL);
126
127 ret = pcie_phy_poll_ack(dbi_base, 1);
128 if (ret)
129 return ret;
130
131 val = addr << PCIE_PHY_CTRL_DATA_LOC;
132 writel(val, dbi_base + PCIE_PHY_CTRL);
133
134 ret = pcie_phy_poll_ack(dbi_base, 0);
135 if (ret)
136 return ret;
137
138 return 0;
139}
140
141/* Read from the 16-bit PCIe PHY control registers (not memory-mapped) */
142static int pcie_phy_read(void __iomem *dbi_base, int addr , int *data)
143{
144 u32 val, phy_ctl;
145 int ret;
146
147 ret = pcie_phy_wait_ack(dbi_base, addr);
148 if (ret)
149 return ret;
150
151 /* assert Read signal */
152 phy_ctl = 0x1 << PCIE_PHY_CTRL_RD_LOC;
153 writel(phy_ctl, dbi_base + PCIE_PHY_CTRL);
154
155 ret = pcie_phy_poll_ack(dbi_base, 1);
156 if (ret)
157 return ret;
158
159 val = readl(dbi_base + PCIE_PHY_STAT);
160 *data = val & 0xffff;
161
162 /* deassert Read signal */
163 writel(0x00, dbi_base + PCIE_PHY_CTRL);
164
165 ret = pcie_phy_poll_ack(dbi_base, 0);
166 if (ret)
167 return ret;
168
169 return 0;
170}
171
172static int pcie_phy_write(void __iomem *dbi_base, int addr, int data)
173{
174 u32 var;
175 int ret;
176
177 /* write addr */
178 /* cap addr */
179 ret = pcie_phy_wait_ack(dbi_base, addr);
180 if (ret)
181 return ret;
182
183 var = data << PCIE_PHY_CTRL_DATA_LOC;
184 writel(var, dbi_base + PCIE_PHY_CTRL);
185
186 /* capture data */
187 var |= (0x1 << PCIE_PHY_CTRL_CAP_DAT_LOC);
188 writel(var, dbi_base + PCIE_PHY_CTRL);
189
190 ret = pcie_phy_poll_ack(dbi_base, 1);
191 if (ret)
192 return ret;
193
194 /* deassert cap data */
195 var = data << PCIE_PHY_CTRL_DATA_LOC;
196 writel(var, dbi_base + PCIE_PHY_CTRL);
197
198 /* wait for ack de-assertion */
199 ret = pcie_phy_poll_ack(dbi_base, 0);
200 if (ret)
201 return ret;
202
203 /* assert wr signal */
204 var = 0x1 << PCIE_PHY_CTRL_WR_LOC;
205 writel(var, dbi_base + PCIE_PHY_CTRL);
206
207 /* wait for ack */
208 ret = pcie_phy_poll_ack(dbi_base, 1);
209 if (ret)
210 return ret;
211
212 /* deassert wr signal */
213 var = data << PCIE_PHY_CTRL_DATA_LOC;
214 writel(var, dbi_base + PCIE_PHY_CTRL);
215
216 /* wait for ack de-assertion */
217 ret = pcie_phy_poll_ack(dbi_base, 0);
218 if (ret)
219 return ret;
220
221 writel(0x0, dbi_base + PCIE_PHY_CTRL);
222
223 return 0;
224}
225
226static int imx6_pcie_link_up(void)
227{
228 u32 rc, ltssm;
229 int rx_valid, temp;
230
231 /* link is debug bit 36, debug register 1 starts at bit 32 */
232 rc = readl(MX6_DBI_ADDR + PCIE_PHY_DEBUG_R1);
233 if ((rc & PCIE_PHY_DEBUG_R1_LINK_UP) &&
234 !(rc & PCIE_PHY_DEBUG_R1_LINK_IN_TRAINING))
235 return -EAGAIN;
236
237 /*
238 * From L0, initiate MAC entry to gen2 if EP/RC supports gen2.
239 * Wait 2ms (LTSSM timeout is 24ms, PHY lock is ~5us in gen2).
240 * If (MAC/LTSSM.state == Recovery.RcvrLock)
241 * && (PHY/rx_valid==0) then pulse PHY/rx_reset. Transition
242 * to gen2 is stuck
243 */
244 pcie_phy_read((void *)MX6_DBI_ADDR, PCIE_PHY_RX_ASIC_OUT, &rx_valid);
245 ltssm = readl(MX6_DBI_ADDR + PCIE_PHY_DEBUG_R0) & 0x3F;
246
247 if (rx_valid & 0x01)
248 return 0;
249
250 if (ltssm != 0x0d)
251 return 0;
252
253 printf("transition to gen2 is stuck, reset PHY!\n");
254
255 pcie_phy_read((void *)MX6_DBI_ADDR, PHY_RX_OVRD_IN_LO, &temp);
256 temp |= (PHY_RX_OVRD_IN_LO_RX_DATA_EN | PHY_RX_OVRD_IN_LO_RX_PLL_EN);
257 pcie_phy_write((void *)MX6_DBI_ADDR, PHY_RX_OVRD_IN_LO, temp);
258
259 udelay(3000);
260
261 pcie_phy_read((void *)MX6_DBI_ADDR, PHY_RX_OVRD_IN_LO, &temp);
262 temp &= ~(PHY_RX_OVRD_IN_LO_RX_DATA_EN | PHY_RX_OVRD_IN_LO_RX_PLL_EN);
263 pcie_phy_write((void *)MX6_DBI_ADDR, PHY_RX_OVRD_IN_LO, temp);
264
265 return 0;
266}
267
268/*
269 * iATU region setup
270 */
271static int imx_pcie_regions_setup(void)
272{
273 /*
274 * i.MX6 defines 16MB in the AXI address map for PCIe.
275 *
276 * That address space excepted the pcie registers is
277 * split and defined into different regions by iATU,
278 * with sizes and offsets as follows:
279 *
280 * 0x0100_0000 --- 0x010F_FFFF 1MB IORESOURCE_IO
281 * 0x0110_0000 --- 0x01EF_FFFF 14MB IORESOURCE_MEM
282 * 0x01F0_0000 --- 0x01FF_FFFF 1MB Cfg + Registers
283 */
284
285 /* CMD reg:I/O space, MEM space, and Bus Master Enable */
286 setbits_le32(MX6_DBI_ADDR | PCI_COMMAND,
287 PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
288
289 /* Set the CLASS_REV of RC CFG header to PCI_CLASS_BRIDGE_PCI */
290 setbits_le32(MX6_DBI_ADDR + PCI_CLASS_REVISION,
291 PCI_CLASS_BRIDGE_PCI << 16);
292
293 /* Region #0 is used for Outbound CFG space access. */
294 writel(0, MX6_DBI_ADDR + PCIE_ATU_VIEWPORT);
295
296 writel(MX6_ROOT_ADDR, MX6_DBI_ADDR + PCIE_ATU_LOWER_BASE);
297 writel(0, MX6_DBI_ADDR + PCIE_ATU_UPPER_BASE);
298 writel(MX6_ROOT_ADDR + MX6_ROOT_SIZE, MX6_DBI_ADDR + PCIE_ATU_LIMIT);
299
300 writel(0, MX6_DBI_ADDR + PCIE_ATU_LOWER_TARGET);
301 writel(0, MX6_DBI_ADDR + PCIE_ATU_UPPER_TARGET);
302 writel(PCIE_ATU_TYPE_CFG0, MX6_DBI_ADDR + PCIE_ATU_CR1);
303 writel(PCIE_ATU_ENABLE, MX6_DBI_ADDR + PCIE_ATU_CR2);
304
305 return 0;
306}
307
308/*
309 * PCI Express accessors
310 */
311static uint32_t get_bus_address(pci_dev_t d, int where)
312{
313 uint32_t va_address;
314
315 /* Reconfigure Region #0 */
316 writel(0, MX6_DBI_ADDR + PCIE_ATU_VIEWPORT);
317
318 if (PCI_BUS(d) < 2)
319 writel(PCIE_ATU_TYPE_CFG0, MX6_DBI_ADDR + PCIE_ATU_CR1);
320 else
321 writel(PCIE_ATU_TYPE_CFG1, MX6_DBI_ADDR + PCIE_ATU_CR1);
322
323 if (PCI_BUS(d) == 0) {
324 va_address = MX6_DBI_ADDR;
325 } else {
326 writel(d << 8, MX6_DBI_ADDR + PCIE_ATU_LOWER_TARGET);
327 va_address = MX6_IO_ADDR + SZ_16M - SZ_1M;
328 }
329
330 va_address += (where & ~0x3);
331
332 return va_address;
333}
334
335static int imx_pcie_addr_valid(pci_dev_t d)
336{
337 if ((PCI_BUS(d) == 0) && (PCI_DEV(d) > 1))
338 return -EINVAL;
339 if ((PCI_BUS(d) == 1) && (PCI_DEV(d) > 0))
340 return -EINVAL;
341 return 0;
342}
343
344/*
345 * Replace the original ARM DABT handler with a simple jump-back one.
346 *
347 * The problem here is that if we have a PCIe bridge attached to this PCIe
348 * controller, but no PCIe device is connected to the bridges' downstream
349 * port, the attempt to read/write from/to the config space will produce
350 * a DABT. This is a behavior of the controller and can not be disabled
351 * unfortuatelly.
352 *
353 * To work around the problem, we backup the current DABT handler address
354 * and replace it with our own DABT handler, which only bounces right back
355 * into the code.
356 */
357static void imx_pcie_fix_dabt_handler(bool set)
358{
359 extern uint32_t *_data_abort;
360 uint32_t *data_abort_addr = (uint32_t *)&_data_abort;
361
362 static const uint32_t data_abort_bounce_handler = 0xe25ef004;
363 uint32_t data_abort_bounce_addr = (uint32_t)&data_abort_bounce_handler;
364
365 static uint32_t data_abort_backup;
366
367 if (set) {
368 data_abort_backup = *data_abort_addr;
369 *data_abort_addr = data_abort_bounce_addr;
370 } else {
371 *data_abort_addr = data_abort_backup;
372 }
373}
374
375static int imx_pcie_read_config(struct pci_controller *hose, pci_dev_t d,
376 int where, u32 *val)
377{
378 uint32_t va_address;
379 int ret;
380
381 ret = imx_pcie_addr_valid(d);
382 if (ret) {
383 *val = 0xffffffff;
384 return ret;
385 }
386
387 va_address = get_bus_address(d, where);
388
389 /*
390 * Read the PCIe config space. We must replace the DABT handler
391 * here in case we got data abort from the PCIe controller, see
392 * imx_pcie_fix_dabt_handler() description. Note that writing the
393 * "val" with valid value is also imperative here as in case we
394 * did got DABT, the val would contain random value.
395 */
396 imx_pcie_fix_dabt_handler(true);
397 writel(0xffffffff, val);
398 *val = readl(va_address);
399 imx_pcie_fix_dabt_handler(false);
400
401 return 0;
402}
403
404static int imx_pcie_write_config(struct pci_controller *hose, pci_dev_t d,
405 int where, u32 val)
406{
407 uint32_t va_address = 0;
408 int ret;
409
410 ret = imx_pcie_addr_valid(d);
411 if (ret)
412 return ret;
413
414 va_address = get_bus_address(d, where);
415
416 /*
417 * Write the PCIe config space. We must replace the DABT handler
418 * here in case we got data abort from the PCIe controller, see
419 * imx_pcie_fix_dabt_handler() description.
420 */
421 imx_pcie_fix_dabt_handler(true);
422 writel(val, va_address);
423 imx_pcie_fix_dabt_handler(false);
424
425 return 0;
426}
427
428/*
429 * Initial bus setup
430 */
431static int imx6_pcie_assert_core_reset(void)
432{
433 struct iomuxc *iomuxc_regs = (struct iomuxc *)IOMUXC_BASE_ADDR;
Fabio Estevamaaf87f02015-10-13 11:01:27 -0300434
435 if (is_mx6dqp())
436 setbits_le32(&iomuxc_regs->gpr[1], IOMUXC_GPR1_PCIE_SW_RST);
437
Fabio Estevam1b8ad742014-08-25 14:26:45 -0300438#if defined(CONFIG_MX6SX)
439 struct gpc *gpc_regs = (struct gpc *)GPC_BASE_ADDR;
Marek Vasute9be4292013-12-14 05:55:28 +0100440
Fabio Estevam1b8ad742014-08-25 14:26:45 -0300441 /* SSP_EN is not used on MX6SX anymore */
442 setbits_le32(&iomuxc_regs->gpr[12], IOMUXC_GPR12_TEST_POWERDOWN);
443 /* Force PCIe PHY reset */
444 setbits_le32(&iomuxc_regs->gpr[5], IOMUXC_GPR5_PCIE_BTNRST);
445 /* Power up PCIe PHY */
446 setbits_le32(&gpc_regs->cntr, PCIE_PHY_PUP_REQ);
447#else
Marek Vasute9be4292013-12-14 05:55:28 +0100448 setbits_le32(&iomuxc_regs->gpr[1], IOMUXC_GPR1_TEST_POWERDOWN);
449 clrbits_le32(&iomuxc_regs->gpr[1], IOMUXC_GPR1_REF_SSP_EN);
Fabio Estevam1b8ad742014-08-25 14:26:45 -0300450#endif
Marek Vasute9be4292013-12-14 05:55:28 +0100451
452 return 0;
453}
454
455static int imx6_pcie_init_phy(void)
456{
457 struct iomuxc *iomuxc_regs = (struct iomuxc *)IOMUXC_BASE_ADDR;
458
459 clrbits_le32(&iomuxc_regs->gpr[12], IOMUXC_GPR12_APPS_LTSSM_ENABLE);
460
461 clrsetbits_le32(&iomuxc_regs->gpr[12],
462 IOMUXC_GPR12_DEVICE_TYPE_MASK,
463 IOMUXC_GPR12_DEVICE_TYPE_RC);
464 clrsetbits_le32(&iomuxc_regs->gpr[12],
465 IOMUXC_GPR12_LOS_LEVEL_MASK,
466 IOMUXC_GPR12_LOS_LEVEL_9);
467
Fabio Estevam1b8ad742014-08-25 14:26:45 -0300468#ifdef CONFIG_MX6SX
469 clrsetbits_le32(&iomuxc_regs->gpr[12],
470 IOMUXC_GPR12_RX_EQ_MASK,
471 IOMUXC_GPR12_RX_EQ_2);
472#endif
473
Marek Vasute9be4292013-12-14 05:55:28 +0100474 writel((0x0 << IOMUXC_GPR8_PCS_TX_DEEMPH_GEN1_OFFSET) |
475 (0x0 << IOMUXC_GPR8_PCS_TX_DEEMPH_GEN2_3P5DB_OFFSET) |
476 (20 << IOMUXC_GPR8_PCS_TX_DEEMPH_GEN2_6DB_OFFSET) |
477 (127 << IOMUXC_GPR8_PCS_TX_SWING_FULL_OFFSET) |
478 (127 << IOMUXC_GPR8_PCS_TX_SWING_LOW_OFFSET),
479 &iomuxc_regs->gpr[8]);
480
481 return 0;
482}
483
Marek Vasuta778aea2014-03-23 22:45:40 +0100484__weak int imx6_pcie_toggle_power(void)
485{
486#ifdef CONFIG_PCIE_IMX_POWER_GPIO
487 gpio_direction_output(CONFIG_PCIE_IMX_POWER_GPIO, 0);
488 mdelay(20);
489 gpio_set_value(CONFIG_PCIE_IMX_POWER_GPIO, 1);
490 mdelay(20);
491#endif
492 return 0;
493}
494
Marek Vasutbb019562014-02-03 21:46:22 +0100495__weak int imx6_pcie_toggle_reset(void)
496{
497 /*
498 * See 'PCI EXPRESS BASE SPECIFICATION, REV 3.0, SECTION 6.6.1'
499 * for detailed understanding of the PCIe CR reset logic.
500 *
501 * The PCIe #PERST reset line _MUST_ be connected, otherwise your
502 * design does not conform to the specification. You must wait at
Fabio Estevam8f6edf62015-09-10 20:45:25 -0300503 * least 20 ms after de-asserting the #PERST so the EP device can
Marek Vasutbb019562014-02-03 21:46:22 +0100504 * do self-initialisation.
505 *
506 * In case your #PERST pin is connected to a plain GPIO pin of the
507 * CPU, you can define CONFIG_PCIE_IMX_PERST_GPIO in your board's
508 * configuration file and the condition below will handle the rest
509 * of the reset toggling.
510 *
511 * In case your #PERST toggling logic is more complex, for example
512 * connected via CPLD or somesuch, you can override this function
513 * in your board file and implement reset logic as needed. You must
Fabio Estevam8f6edf62015-09-10 20:45:25 -0300514 * not forget to wait at least 20 ms after de-asserting #PERST in
Marek Vasutbb019562014-02-03 21:46:22 +0100515 * this case either though.
516 *
517 * In case your #PERST line of the PCIe EP device is not connected
518 * at all, your design is broken and you should fix your design,
519 * otherwise you will observe problems like for example the link
520 * not coming up after rebooting the system back from running Linux
521 * that uses the PCIe as well OR the PCIe link might not come up in
522 * Linux at all in the first place since it's in some non-reset
523 * state due to being previously used in U-Boot.
524 */
525#ifdef CONFIG_PCIE_IMX_PERST_GPIO
526 gpio_direction_output(CONFIG_PCIE_IMX_PERST_GPIO, 0);
527 mdelay(20);
528 gpio_set_value(CONFIG_PCIE_IMX_PERST_GPIO, 1);
529 mdelay(20);
530#else
531 puts("WARNING: Make sure the PCIe #PERST line is connected!\n");
532#endif
533 return 0;
534}
535
Marek Vasute9be4292013-12-14 05:55:28 +0100536static int imx6_pcie_deassert_core_reset(void)
537{
538 struct iomuxc *iomuxc_regs = (struct iomuxc *)IOMUXC_BASE_ADDR;
539
Marek Vasuta778aea2014-03-23 22:45:40 +0100540 imx6_pcie_toggle_power();
Marek Vasute9be4292013-12-14 05:55:28 +0100541
Marek Vasute9be4292013-12-14 05:55:28 +0100542 enable_pcie_clock();
543
Fabio Estevamaaf87f02015-10-13 11:01:27 -0300544 if (is_mx6dqp())
545 clrbits_le32(&iomuxc_regs->gpr[1], IOMUXC_GPR1_PCIE_SW_RST);
546
Marek Vasute9be4292013-12-14 05:55:28 +0100547 /*
548 * Wait for the clock to settle a bit, when the clock are sourced
Fabio Estevam8f6edf62015-09-10 20:45:25 -0300549 * from the CPU, we need about 30 ms to settle.
Marek Vasute9be4292013-12-14 05:55:28 +0100550 */
Marek Vasutbb019562014-02-03 21:46:22 +0100551 mdelay(50);
Marek Vasute9be4292013-12-14 05:55:28 +0100552
Fabio Estevam1b8ad742014-08-25 14:26:45 -0300553#if defined(CONFIG_MX6SX)
554 /* SSP_EN is not used on MX6SX anymore */
555 clrbits_le32(&iomuxc_regs->gpr[12], IOMUXC_GPR12_TEST_POWERDOWN);
556 /* Clear PCIe PHY reset bit */
557 clrbits_le32(&iomuxc_regs->gpr[5], IOMUXC_GPR5_PCIE_BTNRST);
558#else
Tim Harvey5a82e1a2014-08-07 22:57:29 -0700559 /* Enable PCIe */
560 clrbits_le32(&iomuxc_regs->gpr[1], IOMUXC_GPR1_TEST_POWERDOWN);
561 setbits_le32(&iomuxc_regs->gpr[1], IOMUXC_GPR1_REF_SSP_EN);
Fabio Estevam1b8ad742014-08-25 14:26:45 -0300562#endif
Tim Harvey5a82e1a2014-08-07 22:57:29 -0700563
Marek Vasutbb019562014-02-03 21:46:22 +0100564 imx6_pcie_toggle_reset();
Marek Vasute9be4292013-12-14 05:55:28 +0100565
566 return 0;
567}
568
569static int imx_pcie_link_up(void)
570{
571 struct iomuxc *iomuxc_regs = (struct iomuxc *)IOMUXC_BASE_ADDR;
572 uint32_t tmp;
573 int count = 0;
574
575 imx6_pcie_assert_core_reset();
576 imx6_pcie_init_phy();
577 imx6_pcie_deassert_core_reset();
578
579 imx_pcie_regions_setup();
580
581 /*
582 * FIXME: Force the PCIe RC to Gen1 operation
583 * The RC must be forced into Gen1 mode before bringing the link
584 * up, otherwise no downstream devices are detected. After the
585 * link is up, a managed Gen1->Gen2 transition can be initiated.
586 */
587 tmp = readl(MX6_DBI_ADDR + 0x7c);
588 tmp &= ~0xf;
589 tmp |= 0x1;
590 writel(tmp, MX6_DBI_ADDR + 0x7c);
591
592 /* LTSSM enable, starting link. */
593 setbits_le32(&iomuxc_regs->gpr[12], IOMUXC_GPR12_APPS_LTSSM_ENABLE);
594
595 while (!imx6_pcie_link_up()) {
596 udelay(10);
597 count++;
598 if (count >= 2000) {
Tim Harvey378b02d2015-05-08 15:17:10 -0700599#ifdef CONFIG_PCI_SCAN_SHOW
600 puts("PCI: pcie phy link never came up\n");
601#endif
Marek Vasute9be4292013-12-14 05:55:28 +0100602 debug("DEBUG_R0: 0x%08x, DEBUG_R1: 0x%08x\n",
603 readl(MX6_DBI_ADDR + PCIE_PHY_DEBUG_R0),
604 readl(MX6_DBI_ADDR + PCIE_PHY_DEBUG_R1));
605 return -EINVAL;
606 }
607 }
608
609 return 0;
610}
611
612void imx_pcie_init(void)
613{
614 /* Static instance of the controller. */
615 static struct pci_controller pcc;
616 struct pci_controller *hose = &pcc;
617 int ret;
618
619 memset(&pcc, 0, sizeof(pcc));
620
621 /* PCI I/O space */
622 pci_set_region(&hose->regions[0],
623 MX6_IO_ADDR, MX6_IO_ADDR,
624 MX6_IO_SIZE, PCI_REGION_IO);
625
626 /* PCI memory space */
627 pci_set_region(&hose->regions[1],
628 MX6_MEM_ADDR, MX6_MEM_ADDR,
629 MX6_MEM_SIZE, PCI_REGION_MEM);
630
631 /* System memory space */
632 pci_set_region(&hose->regions[2],
633 MMDC0_ARB_BASE_ADDR, MMDC0_ARB_BASE_ADDR,
634 0xefffffff, PCI_REGION_MEM | PCI_REGION_SYS_MEMORY);
635
636 hose->region_count = 3;
637
638 pci_set_ops(hose,
639 pci_hose_read_config_byte_via_dword,
640 pci_hose_read_config_word_via_dword,
641 imx_pcie_read_config,
642 pci_hose_write_config_byte_via_dword,
643 pci_hose_write_config_word_via_dword,
644 imx_pcie_write_config);
645
646 /* Start the controller. */
647 ret = imx_pcie_link_up();
648
649 if (!ret) {
650 pci_register_hose(hose);
651 hose->last_busno = pci_hose_scan(hose);
652 }
653}
654
655/* Probe function. */
656void pci_init_board(void)
657{
658 imx_pcie_init();
659}