1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * PCIe host controller driver for Freescale i.MX6 SoCs
4 *
5 * Copyright (C) 2013 Kosagi
6 * https://www.kosagi.com
7 *
8 * Author: Sean Cross <xobs@kosagi.com>
9 */
10
11 #include <linux/bitfield.h>
12 #include <linux/clk.h>
13 #include <linux/delay.h>
14 #include <linux/gpio.h>
15 #include <linux/kernel.h>
16 #include <linux/mfd/syscon.h>
17 #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
18 #include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
19 #include <linux/module.h>
20 #include <linux/of.h>
21 #include <linux/of_gpio.h>
22 #include <linux/of_address.h>
23 #include <linux/pci.h>
24 #include <linux/platform_device.h>
25 #include <linux/regmap.h>
26 #include <linux/regulator/consumer.h>
27 #include <linux/resource.h>
28 #include <linux/signal.h>
29 #include <linux/types.h>
30 #include <linux/interrupt.h>
31 #include <linux/reset.h>
32 #include <linux/phy/phy.h>
33 #include <linux/pm_domain.h>
34 #include <linux/pm_runtime.h>
35
36 #include "pcie-designware.h"
37
38 #define IMX8MQ_GPR_PCIE_REF_USE_PAD BIT(9)
39 #define IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN BIT(10)
40 #define IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE BIT(11)
41 #define IMX8MQ_GPR_PCIE_VREG_BYPASS BIT(12)
42 #define IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE GENMASK(11, 8)
43 #define IMX8MQ_PCIE2_BASE_ADDR 0x33c00000
44
45 #define to_imx6_pcie(x) dev_get_drvdata((x)->dev)
46
47 enum imx6_pcie_variants {
48 IMX6Q,
49 IMX6SX,
50 IMX6QP,
51 IMX7D,
52 IMX8MQ,
53 IMX8MM,
54 IMX8MP,
55 IMX8MQ_EP,
56 IMX8MM_EP,
57 IMX8MP_EP,
58 };
59
60 #define IMX6_PCIE_FLAG_IMX6_PHY BIT(0)
61 #define IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE BIT(1)
62 #define IMX6_PCIE_FLAG_SUPPORTS_SUSPEND BIT(2)
63
64 struct imx6_pcie_drvdata {
65 enum imx6_pcie_variants variant;
66 enum dw_pcie_device_mode mode;
67 u32 flags;
68 int dbi_length;
69 const char *gpr;
70 };
71
72 struct imx6_pcie {
73 struct dw_pcie *pci;
74 int reset_gpio;
75 bool gpio_active_high;
76 bool link_is_up;
77 struct clk *pcie_bus;
78 struct clk *pcie_phy;
79 struct clk *pcie_inbound_axi;
80 struct clk *pcie;
81 struct clk *pcie_aux;
82 struct regmap *iomuxc_gpr;
83 u16 msi_ctrl;
84 u32 controller_id;
85 struct reset_control *pciephy_reset;
86 struct reset_control *apps_reset;
87 struct reset_control *turnoff_reset;
88 u32 tx_deemph_gen1;
89 u32 tx_deemph_gen2_3p5db;
90 u32 tx_deemph_gen2_6db;
91 u32 tx_swing_full;
92 u32 tx_swing_low;
93 struct regulator *vpcie;
94 struct regulator *vph;
95 void __iomem *phy_base;
96
97 /* power domain for pcie */
98 struct device *pd_pcie;
99 /* power domain for pcie phy */
100 struct device *pd_pcie_phy;
101 struct phy *phy;
102 const struct imx6_pcie_drvdata *drvdata;
103 };
104
105 /* Parameters for the waiting for PCIe PHY PLL to lock on i.MX7 */
106 #define PHY_PLL_LOCK_WAIT_USLEEP_MAX 200
107 #define PHY_PLL_LOCK_WAIT_TIMEOUT (2000 * PHY_PLL_LOCK_WAIT_USLEEP_MAX)
108
109 /* PCIe Port Logic registers (memory-mapped) */
110 #define PL_OFFSET 0x700
111
112 #define PCIE_PHY_CTRL (PL_OFFSET + 0x114)
113 #define PCIE_PHY_CTRL_DATA(x) FIELD_PREP(GENMASK(15, 0), (x))
114 #define PCIE_PHY_CTRL_CAP_ADR BIT(16)
115 #define PCIE_PHY_CTRL_CAP_DAT BIT(17)
116 #define PCIE_PHY_CTRL_WR BIT(18)
117 #define PCIE_PHY_CTRL_RD BIT(19)
118
119 #define PCIE_PHY_STAT (PL_OFFSET + 0x110)
120 #define PCIE_PHY_STAT_ACK BIT(16)
121
122 /* PHY registers (not memory-mapped) */
123 #define PCIE_PHY_ATEOVRD 0x10
124 #define PCIE_PHY_ATEOVRD_EN BIT(2)
125 #define PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT 0
126 #define PCIE_PHY_ATEOVRD_REF_CLKDIV_MASK 0x1
127
128 #define PCIE_PHY_MPLL_OVRD_IN_LO 0x11
129 #define PCIE_PHY_MPLL_MULTIPLIER_SHIFT 2
130 #define PCIE_PHY_MPLL_MULTIPLIER_MASK 0x7f
131 #define PCIE_PHY_MPLL_MULTIPLIER_OVRD BIT(9)
132
133 #define PCIE_PHY_RX_ASIC_OUT 0x100D
134 #define PCIE_PHY_RX_ASIC_OUT_VALID (1 << 0)
135
136 /* iMX7 PCIe PHY registers */
137 #define PCIE_PHY_CMN_REG4 0x14
138 /* These are probably the bits that *aren't* DCC_FB_EN */
139 #define PCIE_PHY_CMN_REG4_DCC_FB_EN 0x29
140
141 #define PCIE_PHY_CMN_REG15 0x54
142 #define PCIE_PHY_CMN_REG15_DLY_4 BIT(2)
143 #define PCIE_PHY_CMN_REG15_PLL_PD BIT(5)
144 #define PCIE_PHY_CMN_REG15_OVRD_PLL_PD BIT(7)
145
146 #define PCIE_PHY_CMN_REG24 0x90
147 #define PCIE_PHY_CMN_REG24_RX_EQ BIT(6)
148 #define PCIE_PHY_CMN_REG24_RX_EQ_SEL BIT(3)
149
150 #define PCIE_PHY_CMN_REG26 0x98
151 #define PCIE_PHY_CMN_REG26_ATT_MODE 0xBC
152
153 #define PHY_RX_OVRD_IN_LO 0x1005
154 #define PHY_RX_OVRD_IN_LO_RX_DATA_EN BIT(5)
155 #define PHY_RX_OVRD_IN_LO_RX_PLL_EN BIT(3)
156
imx6_pcie_grp_offset(const struct imx6_pcie * imx6_pcie)157 static unsigned int imx6_pcie_grp_offset(const struct imx6_pcie *imx6_pcie)
158 {
159 WARN_ON(imx6_pcie->drvdata->variant != IMX8MQ &&
160 imx6_pcie->drvdata->variant != IMX8MQ_EP &&
161 imx6_pcie->drvdata->variant != IMX8MM &&
162 imx6_pcie->drvdata->variant != IMX8MM_EP &&
163 imx6_pcie->drvdata->variant != IMX8MP &&
164 imx6_pcie->drvdata->variant != IMX8MP_EP);
165 return imx6_pcie->controller_id == 1 ? IOMUXC_GPR16 : IOMUXC_GPR14;
166 }
167
imx6_pcie_configure_type(struct imx6_pcie * imx6_pcie)168 static void imx6_pcie_configure_type(struct imx6_pcie *imx6_pcie)
169 {
170 unsigned int mask, val, mode;
171
172 if (imx6_pcie->drvdata->mode == DW_PCIE_EP_TYPE)
173 mode = PCI_EXP_TYPE_ENDPOINT;
174 else
175 mode = PCI_EXP_TYPE_ROOT_PORT;
176
177 switch (imx6_pcie->drvdata->variant) {
178 case IMX8MQ:
179 case IMX8MQ_EP:
180 if (imx6_pcie->controller_id == 1) {
181 mask = IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE;
182 val = FIELD_PREP(IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE,
183 mode);
184 } else {
185 mask = IMX6Q_GPR12_DEVICE_TYPE;
186 val = FIELD_PREP(IMX6Q_GPR12_DEVICE_TYPE, mode);
187 }
188 break;
189 default:
190 mask = IMX6Q_GPR12_DEVICE_TYPE;
191 val = FIELD_PREP(IMX6Q_GPR12_DEVICE_TYPE, mode);
192 break;
193 }
194
195 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, mask, val);
196 }
197
pcie_phy_poll_ack(struct imx6_pcie * imx6_pcie,bool exp_val)198 static int pcie_phy_poll_ack(struct imx6_pcie *imx6_pcie, bool exp_val)
199 {
200 struct dw_pcie *pci = imx6_pcie->pci;
201 bool val;
202 u32 max_iterations = 10;
203 u32 wait_counter = 0;
204
205 do {
206 val = dw_pcie_readl_dbi(pci, PCIE_PHY_STAT) &
207 PCIE_PHY_STAT_ACK;
208 wait_counter++;
209
210 if (val == exp_val)
211 return 0;
212
213 udelay(1);
214 } while (wait_counter < max_iterations);
215
216 return -ETIMEDOUT;
217 }
218
pcie_phy_wait_ack(struct imx6_pcie * imx6_pcie,int addr)219 static int pcie_phy_wait_ack(struct imx6_pcie *imx6_pcie, int addr)
220 {
221 struct dw_pcie *pci = imx6_pcie->pci;
222 u32 val;
223 int ret;
224
225 val = PCIE_PHY_CTRL_DATA(addr);
226 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
227
228 val |= PCIE_PHY_CTRL_CAP_ADR;
229 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
230
231 ret = pcie_phy_poll_ack(imx6_pcie, true);
232 if (ret)
233 return ret;
234
235 val = PCIE_PHY_CTRL_DATA(addr);
236 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
237
238 return pcie_phy_poll_ack(imx6_pcie, false);
239 }
240
241 /* Read from the 16-bit PCIe PHY control registers (not memory-mapped) */
pcie_phy_read(struct imx6_pcie * imx6_pcie,int addr,u16 * data)242 static int pcie_phy_read(struct imx6_pcie *imx6_pcie, int addr, u16 *data)
243 {
244 struct dw_pcie *pci = imx6_pcie->pci;
245 u32 phy_ctl;
246 int ret;
247
248 ret = pcie_phy_wait_ack(imx6_pcie, addr);
249 if (ret)
250 return ret;
251
252 /* assert Read signal */
253 phy_ctl = PCIE_PHY_CTRL_RD;
254 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, phy_ctl);
255
256 ret = pcie_phy_poll_ack(imx6_pcie, true);
257 if (ret)
258 return ret;
259
260 *data = dw_pcie_readl_dbi(pci, PCIE_PHY_STAT);
261
262 /* deassert Read signal */
263 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, 0x00);
264
265 return pcie_phy_poll_ack(imx6_pcie, false);
266 }
267
pcie_phy_write(struct imx6_pcie * imx6_pcie,int addr,u16 data)268 static int pcie_phy_write(struct imx6_pcie *imx6_pcie, int addr, u16 data)
269 {
270 struct dw_pcie *pci = imx6_pcie->pci;
271 u32 var;
272 int ret;
273
274 /* write addr */
275 /* cap addr */
276 ret = pcie_phy_wait_ack(imx6_pcie, addr);
277 if (ret)
278 return ret;
279
280 var = PCIE_PHY_CTRL_DATA(data);
281 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
282
283 /* capture data */
284 var |= PCIE_PHY_CTRL_CAP_DAT;
285 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
286
287 ret = pcie_phy_poll_ack(imx6_pcie, true);
288 if (ret)
289 return ret;
290
291 /* deassert cap data */
292 var = PCIE_PHY_CTRL_DATA(data);
293 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
294
295 /* wait for ack de-assertion */
296 ret = pcie_phy_poll_ack(imx6_pcie, false);
297 if (ret)
298 return ret;
299
300 /* assert wr signal */
301 var = PCIE_PHY_CTRL_WR;
302 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
303
304 /* wait for ack */
305 ret = pcie_phy_poll_ack(imx6_pcie, true);
306 if (ret)
307 return ret;
308
309 /* deassert wr signal */
310 var = PCIE_PHY_CTRL_DATA(data);
311 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
312
313 /* wait for ack de-assertion */
314 ret = pcie_phy_poll_ack(imx6_pcie, false);
315 if (ret)
316 return ret;
317
318 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, 0x0);
319
320 return 0;
321 }
322
imx6_pcie_init_phy(struct imx6_pcie * imx6_pcie)323 static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie)
324 {
325 switch (imx6_pcie->drvdata->variant) {
326 case IMX8MM:
327 case IMX8MM_EP:
328 case IMX8MP:
329 case IMX8MP_EP:
330 /*
331 * The PHY initialization had been done in the PHY
332 * driver, break here directly.
333 */
334 break;
335 case IMX8MQ:
336 case IMX8MQ_EP:
337 /*
338 * TODO: Currently this code assumes external
339 * oscillator is being used
340 */
341 regmap_update_bits(imx6_pcie->iomuxc_gpr,
342 imx6_pcie_grp_offset(imx6_pcie),
343 IMX8MQ_GPR_PCIE_REF_USE_PAD,
344 IMX8MQ_GPR_PCIE_REF_USE_PAD);
345 /*
346 * Regarding the datasheet, the PCIE_VPH is suggested
347 * to be 1.8V. If the PCIE_VPH is supplied by 3.3V, the
348 * VREG_BYPASS should be cleared to zero.
349 */
350 if (imx6_pcie->vph &&
351 regulator_get_voltage(imx6_pcie->vph) > 3000000)
352 regmap_update_bits(imx6_pcie->iomuxc_gpr,
353 imx6_pcie_grp_offset(imx6_pcie),
354 IMX8MQ_GPR_PCIE_VREG_BYPASS,
355 0);
356 break;
357 case IMX7D:
358 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
359 IMX7D_GPR12_PCIE_PHY_REFCLK_SEL, 0);
360 break;
361 case IMX6SX:
362 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
363 IMX6SX_GPR12_PCIE_RX_EQ_MASK,
364 IMX6SX_GPR12_PCIE_RX_EQ_2);
365 fallthrough;
366 default:
367 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
368 IMX6Q_GPR12_PCIE_CTL_2, 0 << 10);
369
370 /* configure constant input signal to the pcie ctrl and phy */
371 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
372 IMX6Q_GPR12_LOS_LEVEL, 9 << 4);
373
374 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
375 IMX6Q_GPR8_TX_DEEMPH_GEN1,
376 imx6_pcie->tx_deemph_gen1 << 0);
377 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
378 IMX6Q_GPR8_TX_DEEMPH_GEN2_3P5DB,
379 imx6_pcie->tx_deemph_gen2_3p5db << 6);
380 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
381 IMX6Q_GPR8_TX_DEEMPH_GEN2_6DB,
382 imx6_pcie->tx_deemph_gen2_6db << 12);
383 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
384 IMX6Q_GPR8_TX_SWING_FULL,
385 imx6_pcie->tx_swing_full << 18);
386 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
387 IMX6Q_GPR8_TX_SWING_LOW,
388 imx6_pcie->tx_swing_low << 25);
389 break;
390 }
391
392 imx6_pcie_configure_type(imx6_pcie);
393 }
394
imx7d_pcie_wait_for_phy_pll_lock(struct imx6_pcie * imx6_pcie)395 static void imx7d_pcie_wait_for_phy_pll_lock(struct imx6_pcie *imx6_pcie)
396 {
397 u32 val;
398 struct device *dev = imx6_pcie->pci->dev;
399
400 if (regmap_read_poll_timeout(imx6_pcie->iomuxc_gpr,
401 IOMUXC_GPR22, val,
402 val & IMX7D_GPR22_PCIE_PHY_PLL_LOCKED,
403 PHY_PLL_LOCK_WAIT_USLEEP_MAX,
404 PHY_PLL_LOCK_WAIT_TIMEOUT))
405 dev_err(dev, "PCIe PLL lock timeout\n");
406 }
407
imx6_setup_phy_mpll(struct imx6_pcie * imx6_pcie)408 static int imx6_setup_phy_mpll(struct imx6_pcie *imx6_pcie)
409 {
410 unsigned long phy_rate = clk_get_rate(imx6_pcie->pcie_phy);
411 int mult, div;
412 u16 val;
413
414 if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_IMX6_PHY))
415 return 0;
416
417 switch (phy_rate) {
418 case 125000000:
419 /*
420 * The default settings of the MPLL are for a 125MHz input
421 * clock, so no need to reconfigure anything in that case.
422 */
423 return 0;
424 case 100000000:
425 mult = 25;
426 div = 0;
427 break;
428 case 200000000:
429 mult = 25;
430 div = 1;
431 break;
432 default:
433 dev_err(imx6_pcie->pci->dev,
434 "Unsupported PHY reference clock rate %lu\n", phy_rate);
435 return -EINVAL;
436 }
437
438 pcie_phy_read(imx6_pcie, PCIE_PHY_MPLL_OVRD_IN_LO, &val);
439 val &= ~(PCIE_PHY_MPLL_MULTIPLIER_MASK <<
440 PCIE_PHY_MPLL_MULTIPLIER_SHIFT);
441 val |= mult << PCIE_PHY_MPLL_MULTIPLIER_SHIFT;
442 val |= PCIE_PHY_MPLL_MULTIPLIER_OVRD;
443 pcie_phy_write(imx6_pcie, PCIE_PHY_MPLL_OVRD_IN_LO, val);
444
445 pcie_phy_read(imx6_pcie, PCIE_PHY_ATEOVRD, &val);
446 val &= ~(PCIE_PHY_ATEOVRD_REF_CLKDIV_MASK <<
447 PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT);
448 val |= div << PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT;
449 val |= PCIE_PHY_ATEOVRD_EN;
450 pcie_phy_write(imx6_pcie, PCIE_PHY_ATEOVRD, val);
451
452 return 0;
453 }
454
imx6_pcie_reset_phy(struct imx6_pcie * imx6_pcie)455 static void imx6_pcie_reset_phy(struct imx6_pcie *imx6_pcie)
456 {
457 u16 tmp;
458
459 if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_IMX6_PHY))
460 return;
461
462 pcie_phy_read(imx6_pcie, PHY_RX_OVRD_IN_LO, &tmp);
463 tmp |= (PHY_RX_OVRD_IN_LO_RX_DATA_EN |
464 PHY_RX_OVRD_IN_LO_RX_PLL_EN);
465 pcie_phy_write(imx6_pcie, PHY_RX_OVRD_IN_LO, tmp);
466
467 usleep_range(2000, 3000);
468
469 pcie_phy_read(imx6_pcie, PHY_RX_OVRD_IN_LO, &tmp);
470 tmp &= ~(PHY_RX_OVRD_IN_LO_RX_DATA_EN |
471 PHY_RX_OVRD_IN_LO_RX_PLL_EN);
472 pcie_phy_write(imx6_pcie, PHY_RX_OVRD_IN_LO, tmp);
473 }
474
475 #ifdef CONFIG_ARM
476 /* Added for PCI abort handling */
imx6q_pcie_abort_handler(unsigned long addr,unsigned int fsr,struct pt_regs * regs)477 static int imx6q_pcie_abort_handler(unsigned long addr,
478 unsigned int fsr, struct pt_regs *regs)
479 {
480 unsigned long pc = instruction_pointer(regs);
481 unsigned long instr = *(unsigned long *)pc;
482 int reg = (instr >> 12) & 15;
483
484 /*
485 * If the instruction being executed was a read,
486 * make it look like it read all-ones.
487 */
488 if ((instr & 0x0c100000) == 0x04100000) {
489 unsigned long val;
490
491 if (instr & 0x00400000)
492 val = 255;
493 else
494 val = -1;
495
496 regs->uregs[reg] = val;
497 regs->ARM_pc += 4;
498 return 0;
499 }
500
501 if ((instr & 0x0e100090) == 0x00100090) {
502 regs->uregs[reg] = -1;
503 regs->ARM_pc += 4;
504 return 0;
505 }
506
507 return 1;
508 }
509 #endif
510
imx6_pcie_attach_pd(struct device * dev)511 static int imx6_pcie_attach_pd(struct device *dev)
512 {
513 struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
514 struct device_link *link;
515
516 /* Do nothing when in a single power domain */
517 if (dev->pm_domain)
518 return 0;
519
520 imx6_pcie->pd_pcie = dev_pm_domain_attach_by_name(dev, "pcie");
521 if (IS_ERR(imx6_pcie->pd_pcie))
522 return PTR_ERR(imx6_pcie->pd_pcie);
523 /* Do nothing when power domain missing */
524 if (!imx6_pcie->pd_pcie)
525 return 0;
526 link = device_link_add(dev, imx6_pcie->pd_pcie,
527 DL_FLAG_STATELESS |
528 DL_FLAG_PM_RUNTIME |
529 DL_FLAG_RPM_ACTIVE);
530 if (!link) {
531 dev_err(dev, "Failed to add device_link to pcie pd.\n");
532 return -EINVAL;
533 }
534
535 imx6_pcie->pd_pcie_phy = dev_pm_domain_attach_by_name(dev, "pcie_phy");
536 if (IS_ERR(imx6_pcie->pd_pcie_phy))
537 return PTR_ERR(imx6_pcie->pd_pcie_phy);
538
539 link = device_link_add(dev, imx6_pcie->pd_pcie_phy,
540 DL_FLAG_STATELESS |
541 DL_FLAG_PM_RUNTIME |
542 DL_FLAG_RPM_ACTIVE);
543 if (!link) {
544 dev_err(dev, "Failed to add device_link to pcie_phy pd.\n");
545 return -EINVAL;
546 }
547
548 return 0;
549 }
550
imx6_pcie_enable_ref_clk(struct imx6_pcie * imx6_pcie)551 static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie)
552 {
553 struct dw_pcie *pci = imx6_pcie->pci;
554 struct device *dev = pci->dev;
555 unsigned int offset;
556 int ret = 0;
557
558 switch (imx6_pcie->drvdata->variant) {
559 case IMX6SX:
560 ret = clk_prepare_enable(imx6_pcie->pcie_inbound_axi);
561 if (ret) {
562 dev_err(dev, "unable to enable pcie_axi clock\n");
563 break;
564 }
565
566 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
567 IMX6SX_GPR12_PCIE_TEST_POWERDOWN, 0);
568 break;
569 case IMX6QP:
570 case IMX6Q:
571 /* power up core phy and enable ref clock */
572 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
573 IMX6Q_GPR1_PCIE_TEST_PD, 0 << 18);
574 /*
575 * the async reset input need ref clock to sync internally,
576 * when the ref clock comes after reset, internal synced
577 * reset time is too short, cannot meet the requirement.
578 * add one ~10us delay here.
579 */
580 usleep_range(10, 100);
581 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
582 IMX6Q_GPR1_PCIE_REF_CLK_EN, 1 << 16);
583 break;
584 case IMX7D:
585 break;
586 case IMX8MM:
587 case IMX8MM_EP:
588 case IMX8MQ:
589 case IMX8MQ_EP:
590 case IMX8MP:
591 case IMX8MP_EP:
592 ret = clk_prepare_enable(imx6_pcie->pcie_aux);
593 if (ret) {
594 dev_err(dev, "unable to enable pcie_aux clock\n");
595 break;
596 }
597
598 offset = imx6_pcie_grp_offset(imx6_pcie);
599 /*
600 * Set the over ride low and enabled
601 * make sure that REF_CLK is turned on.
602 */
603 regmap_update_bits(imx6_pcie->iomuxc_gpr, offset,
604 IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE,
605 0);
606 regmap_update_bits(imx6_pcie->iomuxc_gpr, offset,
607 IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN,
608 IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN);
609 break;
610 }
611
612 return ret;
613 }
614
imx6_pcie_disable_ref_clk(struct imx6_pcie * imx6_pcie)615 static void imx6_pcie_disable_ref_clk(struct imx6_pcie *imx6_pcie)
616 {
617 switch (imx6_pcie->drvdata->variant) {
618 case IMX6SX:
619 clk_disable_unprepare(imx6_pcie->pcie_inbound_axi);
620 break;
621 case IMX6QP:
622 case IMX6Q:
623 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
624 IMX6Q_GPR1_PCIE_REF_CLK_EN, 0);
625 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
626 IMX6Q_GPR1_PCIE_TEST_PD,
627 IMX6Q_GPR1_PCIE_TEST_PD);
628 break;
629 case IMX7D:
630 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
631 IMX7D_GPR12_PCIE_PHY_REFCLK_SEL,
632 IMX7D_GPR12_PCIE_PHY_REFCLK_SEL);
633 break;
634 case IMX8MM:
635 case IMX8MM_EP:
636 case IMX8MQ:
637 case IMX8MQ_EP:
638 case IMX8MP:
639 case IMX8MP_EP:
640 clk_disable_unprepare(imx6_pcie->pcie_aux);
641 break;
642 default:
643 break;
644 }
645 }
646
imx6_pcie_clk_enable(struct imx6_pcie * imx6_pcie)647 static int imx6_pcie_clk_enable(struct imx6_pcie *imx6_pcie)
648 {
649 struct dw_pcie *pci = imx6_pcie->pci;
650 struct device *dev = pci->dev;
651 int ret;
652
653 ret = clk_prepare_enable(imx6_pcie->pcie_phy);
654 if (ret) {
655 dev_err(dev, "unable to enable pcie_phy clock\n");
656 return ret;
657 }
658
659 ret = clk_prepare_enable(imx6_pcie->pcie_bus);
660 if (ret) {
661 dev_err(dev, "unable to enable pcie_bus clock\n");
662 goto err_pcie_bus;
663 }
664
665 ret = clk_prepare_enable(imx6_pcie->pcie);
666 if (ret) {
667 dev_err(dev, "unable to enable pcie clock\n");
668 goto err_pcie;
669 }
670
671 ret = imx6_pcie_enable_ref_clk(imx6_pcie);
672 if (ret) {
673 dev_err(dev, "unable to enable pcie ref clock\n");
674 goto err_ref_clk;
675 }
676
677 /* allow the clocks to stabilize */
678 usleep_range(200, 500);
679 return 0;
680
681 err_ref_clk:
682 clk_disable_unprepare(imx6_pcie->pcie);
683 err_pcie:
684 clk_disable_unprepare(imx6_pcie->pcie_bus);
685 err_pcie_bus:
686 clk_disable_unprepare(imx6_pcie->pcie_phy);
687
688 return ret;
689 }
690
imx6_pcie_clk_disable(struct imx6_pcie * imx6_pcie)691 static void imx6_pcie_clk_disable(struct imx6_pcie *imx6_pcie)
692 {
693 imx6_pcie_disable_ref_clk(imx6_pcie);
694 clk_disable_unprepare(imx6_pcie->pcie);
695 clk_disable_unprepare(imx6_pcie->pcie_bus);
696 clk_disable_unprepare(imx6_pcie->pcie_phy);
697 }
698
imx6_pcie_assert_core_reset(struct imx6_pcie * imx6_pcie)699 static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
700 {
701 switch (imx6_pcie->drvdata->variant) {
702 case IMX7D:
703 case IMX8MQ:
704 case IMX8MQ_EP:
705 reset_control_assert(imx6_pcie->pciephy_reset);
706 fallthrough;
707 case IMX8MM:
708 case IMX8MM_EP:
709 case IMX8MP:
710 case IMX8MP_EP:
711 reset_control_assert(imx6_pcie->apps_reset);
712 break;
713 case IMX6SX:
714 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
715 IMX6SX_GPR12_PCIE_TEST_POWERDOWN,
716 IMX6SX_GPR12_PCIE_TEST_POWERDOWN);
717 /* Force PCIe PHY reset */
718 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5,
719 IMX6SX_GPR5_PCIE_BTNRST_RESET,
720 IMX6SX_GPR5_PCIE_BTNRST_RESET);
721 break;
722 case IMX6QP:
723 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
724 IMX6Q_GPR1_PCIE_SW_RST,
725 IMX6Q_GPR1_PCIE_SW_RST);
726 break;
727 case IMX6Q:
728 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
729 IMX6Q_GPR1_PCIE_TEST_PD, 1 << 18);
730 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
731 IMX6Q_GPR1_PCIE_REF_CLK_EN, 0 << 16);
732 break;
733 }
734
735 /* Some boards don't have PCIe reset GPIO. */
736 if (gpio_is_valid(imx6_pcie->reset_gpio))
737 gpio_set_value_cansleep(imx6_pcie->reset_gpio,
738 imx6_pcie->gpio_active_high);
739 }
740
imx6_pcie_deassert_core_reset(struct imx6_pcie * imx6_pcie)741 static int imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
742 {
743 struct dw_pcie *pci = imx6_pcie->pci;
744 struct device *dev = pci->dev;
745
746 switch (imx6_pcie->drvdata->variant) {
747 case IMX8MQ:
748 case IMX8MQ_EP:
749 reset_control_deassert(imx6_pcie->pciephy_reset);
750 break;
751 case IMX7D:
752 reset_control_deassert(imx6_pcie->pciephy_reset);
753
754 /* Workaround for ERR010728, failure of PCI-e PLL VCO to
755 * oscillate, especially when cold. This turns off "Duty-cycle
756 * Corrector" and other mysterious undocumented things.
757 */
758 if (likely(imx6_pcie->phy_base)) {
759 /* De-assert DCC_FB_EN */
760 writel(PCIE_PHY_CMN_REG4_DCC_FB_EN,
761 imx6_pcie->phy_base + PCIE_PHY_CMN_REG4);
762 /* Assert RX_EQS and RX_EQS_SEL */
763 writel(PCIE_PHY_CMN_REG24_RX_EQ_SEL
764 | PCIE_PHY_CMN_REG24_RX_EQ,
765 imx6_pcie->phy_base + PCIE_PHY_CMN_REG24);
766 /* Assert ATT_MODE */
767 writel(PCIE_PHY_CMN_REG26_ATT_MODE,
768 imx6_pcie->phy_base + PCIE_PHY_CMN_REG26);
769 } else {
770 dev_warn(dev, "Unable to apply ERR010728 workaround. DT missing fsl,imx7d-pcie-phy phandle ?\n");
771 }
772
773 imx7d_pcie_wait_for_phy_pll_lock(imx6_pcie);
774 break;
775 case IMX6SX:
776 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5,
777 IMX6SX_GPR5_PCIE_BTNRST_RESET, 0);
778 break;
779 case IMX6QP:
780 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
781 IMX6Q_GPR1_PCIE_SW_RST, 0);
782
783 usleep_range(200, 500);
784 break;
785 case IMX6Q: /* Nothing to do */
786 case IMX8MM:
787 case IMX8MM_EP:
788 case IMX8MP:
789 case IMX8MP_EP:
790 break;
791 }
792
793 /* Some boards don't have PCIe reset GPIO. */
794 if (gpio_is_valid(imx6_pcie->reset_gpio)) {
795 msleep(100);
796 gpio_set_value_cansleep(imx6_pcie->reset_gpio,
797 !imx6_pcie->gpio_active_high);
798 /* Wait for 100ms after PERST# deassertion (PCIe r5.0, 6.6.1) */
799 msleep(100);
800 }
801
802 return 0;
803 }
804
imx6_pcie_wait_for_speed_change(struct imx6_pcie * imx6_pcie)805 static int imx6_pcie_wait_for_speed_change(struct imx6_pcie *imx6_pcie)
806 {
807 struct dw_pcie *pci = imx6_pcie->pci;
808 struct device *dev = pci->dev;
809 u32 tmp;
810 unsigned int retries;
811
812 for (retries = 0; retries < 200; retries++) {
813 tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
814 /* Test if the speed change finished. */
815 if (!(tmp & PORT_LOGIC_SPEED_CHANGE))
816 return 0;
817 usleep_range(100, 1000);
818 }
819
820 dev_err(dev, "Speed change timeout\n");
821 return -ETIMEDOUT;
822 }
823
imx6_pcie_ltssm_enable(struct device * dev)824 static void imx6_pcie_ltssm_enable(struct device *dev)
825 {
826 struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
827
828 switch (imx6_pcie->drvdata->variant) {
829 case IMX6Q:
830 case IMX6SX:
831 case IMX6QP:
832 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
833 IMX6Q_GPR12_PCIE_CTL_2,
834 IMX6Q_GPR12_PCIE_CTL_2);
835 break;
836 case IMX7D:
837 case IMX8MQ:
838 case IMX8MQ_EP:
839 case IMX8MM:
840 case IMX8MM_EP:
841 case IMX8MP:
842 case IMX8MP_EP:
843 reset_control_deassert(imx6_pcie->apps_reset);
844 break;
845 }
846 }
847
imx6_pcie_ltssm_disable(struct device * dev)848 static void imx6_pcie_ltssm_disable(struct device *dev)
849 {
850 struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
851
852 switch (imx6_pcie->drvdata->variant) {
853 case IMX6Q:
854 case IMX6SX:
855 case IMX6QP:
856 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
857 IMX6Q_GPR12_PCIE_CTL_2, 0);
858 break;
859 case IMX7D:
860 case IMX8MQ:
861 case IMX8MQ_EP:
862 case IMX8MM:
863 case IMX8MM_EP:
864 case IMX8MP:
865 case IMX8MP_EP:
866 reset_control_assert(imx6_pcie->apps_reset);
867 break;
868 }
869 }
870
imx6_pcie_start_link(struct dw_pcie * pci)871 static int imx6_pcie_start_link(struct dw_pcie *pci)
872 {
873 struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci);
874 struct device *dev = pci->dev;
875 u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
876 u32 tmp;
877 int ret;
878
879 /*
880 * Force Gen1 operation when starting the link. In case the link is
881 * started in Gen2 mode, there is a possibility the devices on the
882 * bus will not be detected at all. This happens with PCIe switches.
883 */
884 dw_pcie_dbi_ro_wr_en(pci);
885 tmp = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP);
886 tmp &= ~PCI_EXP_LNKCAP_SLS;
887 tmp |= PCI_EXP_LNKCAP_SLS_2_5GB;
888 dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, tmp);
889 dw_pcie_dbi_ro_wr_dis(pci);
890
891 /* Start LTSSM. */
892 imx6_pcie_ltssm_enable(dev);
893
894 ret = dw_pcie_wait_for_link(pci);
895 if (ret)
896 goto err_reset_phy;
897
898 if (pci->link_gen > 1) {
899 /* Allow faster modes after the link is up */
900 dw_pcie_dbi_ro_wr_en(pci);
901 tmp = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP);
902 tmp &= ~PCI_EXP_LNKCAP_SLS;
903 tmp |= pci->link_gen;
904 dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, tmp);
905
906 /*
907 * Start Directed Speed Change so the best possible
908 * speed both link partners support can be negotiated.
909 */
910 tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
911 tmp |= PORT_LOGIC_SPEED_CHANGE;
912 dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, tmp);
913 dw_pcie_dbi_ro_wr_dis(pci);
914
915 if (imx6_pcie->drvdata->flags &
916 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE) {
917 /*
918 * On i.MX7, DIRECT_SPEED_CHANGE behaves differently
919 * from i.MX6 family when no link speed transition
920 * occurs and we go Gen1 -> yep, Gen1. The difference
921 * is that, in such case, it will not be cleared by HW
922 * which will cause the following code to report false
923 * failure.
924 */
925
926 ret = imx6_pcie_wait_for_speed_change(imx6_pcie);
927 if (ret) {
928 dev_err(dev, "Failed to bring link up!\n");
929 goto err_reset_phy;
930 }
931 }
932
933 /* Make sure link training is finished as well! */
934 ret = dw_pcie_wait_for_link(pci);
935 if (ret)
936 goto err_reset_phy;
937 } else {
938 dev_info(dev, "Link: Only Gen1 is enabled\n");
939 }
940
941 imx6_pcie->link_is_up = true;
942 tmp = dw_pcie_readw_dbi(pci, offset + PCI_EXP_LNKSTA);
943 dev_info(dev, "Link up, Gen%i\n", tmp & PCI_EXP_LNKSTA_CLS);
944 return 0;
945
946 err_reset_phy:
947 imx6_pcie->link_is_up = false;
948 dev_dbg(dev, "PHY DEBUG_R0=0x%08x DEBUG_R1=0x%08x\n",
949 dw_pcie_readl_dbi(pci, PCIE_PORT_DEBUG0),
950 dw_pcie_readl_dbi(pci, PCIE_PORT_DEBUG1));
951 imx6_pcie_reset_phy(imx6_pcie);
952 return 0;
953 }
954
imx6_pcie_stop_link(struct dw_pcie * pci)955 static void imx6_pcie_stop_link(struct dw_pcie *pci)
956 {
957 struct device *dev = pci->dev;
958
959 /* Turn off PCIe LTSSM */
960 imx6_pcie_ltssm_disable(dev);
961 }
962
imx6_pcie_host_init(struct dw_pcie_rp * pp)963 static int imx6_pcie_host_init(struct dw_pcie_rp *pp)
964 {
965 struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
966 struct device *dev = pci->dev;
967 struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci);
968 int ret;
969
970 if (imx6_pcie->vpcie) {
971 ret = regulator_enable(imx6_pcie->vpcie);
972 if (ret) {
973 dev_err(dev, "failed to enable vpcie regulator: %d\n",
974 ret);
975 return ret;
976 }
977 }
978
979 imx6_pcie_assert_core_reset(imx6_pcie);
980 imx6_pcie_init_phy(imx6_pcie);
981
982 ret = imx6_pcie_clk_enable(imx6_pcie);
983 if (ret) {
984 dev_err(dev, "unable to enable pcie clocks: %d\n", ret);
985 goto err_reg_disable;
986 }
987
988 if (imx6_pcie->phy) {
989 ret = phy_init(imx6_pcie->phy);
990 if (ret) {
991 dev_err(dev, "pcie PHY power up failed\n");
992 goto err_clk_disable;
993 }
994 }
995
996 if (imx6_pcie->phy) {
997 ret = phy_power_on(imx6_pcie->phy);
998 if (ret) {
999 dev_err(dev, "waiting for PHY ready timeout!\n");
1000 goto err_phy_exit;
1001 }
1002 }
1003
1004 ret = imx6_pcie_deassert_core_reset(imx6_pcie);
1005 if (ret < 0) {
1006 dev_err(dev, "pcie deassert core reset failed: %d\n", ret);
1007 goto err_phy_off;
1008 }
1009
1010 imx6_setup_phy_mpll(imx6_pcie);
1011
1012 return 0;
1013
1014 err_phy_off:
1015 phy_power_off(imx6_pcie->phy);
1016 err_phy_exit:
1017 phy_exit(imx6_pcie->phy);
1018 err_clk_disable:
1019 imx6_pcie_clk_disable(imx6_pcie);
1020 err_reg_disable:
1021 if (imx6_pcie->vpcie)
1022 regulator_disable(imx6_pcie->vpcie);
1023 return ret;
1024 }
1025
imx6_pcie_host_exit(struct dw_pcie_rp * pp)1026 static void imx6_pcie_host_exit(struct dw_pcie_rp *pp)
1027 {
1028 struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
1029 struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci);
1030
1031 if (imx6_pcie->phy) {
1032 if (phy_power_off(imx6_pcie->phy))
1033 dev_err(pci->dev, "unable to power off PHY\n");
1034 phy_exit(imx6_pcie->phy);
1035 }
1036 imx6_pcie_clk_disable(imx6_pcie);
1037
1038 if (imx6_pcie->vpcie)
1039 regulator_disable(imx6_pcie->vpcie);
1040 }
1041
1042 static const struct dw_pcie_host_ops imx6_pcie_host_ops = {
1043 .host_init = imx6_pcie_host_init,
1044 .host_deinit = imx6_pcie_host_exit,
1045 };
1046
1047 static const struct dw_pcie_ops dw_pcie_ops = {
1048 .start_link = imx6_pcie_start_link,
1049 .stop_link = imx6_pcie_stop_link,
1050 };
1051
imx6_pcie_ep_init(struct dw_pcie_ep * ep)1052 static void imx6_pcie_ep_init(struct dw_pcie_ep *ep)
1053 {
1054 enum pci_barno bar;
1055 struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
1056
1057 for (bar = BAR_0; bar <= BAR_5; bar++)
1058 dw_pcie_ep_reset_bar(pci, bar);
1059 }
1060
imx6_pcie_ep_raise_irq(struct dw_pcie_ep * ep,u8 func_no,enum pci_epc_irq_type type,u16 interrupt_num)1061 static int imx6_pcie_ep_raise_irq(struct dw_pcie_ep *ep, u8 func_no,
1062 enum pci_epc_irq_type type,
1063 u16 interrupt_num)
1064 {
1065 struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
1066
1067 switch (type) {
1068 case PCI_EPC_IRQ_LEGACY:
1069 return dw_pcie_ep_raise_legacy_irq(ep, func_no);
1070 case PCI_EPC_IRQ_MSI:
1071 return dw_pcie_ep_raise_msi_irq(ep, func_no, interrupt_num);
1072 case PCI_EPC_IRQ_MSIX:
1073 return dw_pcie_ep_raise_msix_irq(ep, func_no, interrupt_num);
1074 default:
1075 dev_err(pci->dev, "UNKNOWN IRQ type\n");
1076 return -EINVAL;
1077 }
1078
1079 return 0;
1080 }
1081
1082 static const struct pci_epc_features imx8m_pcie_epc_features = {
1083 .linkup_notifier = false,
1084 .msi_capable = true,
1085 .msix_capable = false,
1086 .reserved_bar = 1 << BAR_1 | 1 << BAR_3,
1087 .align = SZ_64K,
1088 };
1089
1090 static const struct pci_epc_features*
imx6_pcie_ep_get_features(struct dw_pcie_ep * ep)1091 imx6_pcie_ep_get_features(struct dw_pcie_ep *ep)
1092 {
1093 return &imx8m_pcie_epc_features;
1094 }
1095
1096 static const struct dw_pcie_ep_ops pcie_ep_ops = {
1097 .ep_init = imx6_pcie_ep_init,
1098 .raise_irq = imx6_pcie_ep_raise_irq,
1099 .get_features = imx6_pcie_ep_get_features,
1100 };
1101
imx6_add_pcie_ep(struct imx6_pcie * imx6_pcie,struct platform_device * pdev)1102 static int imx6_add_pcie_ep(struct imx6_pcie *imx6_pcie,
1103 struct platform_device *pdev)
1104 {
1105 int ret;
1106 unsigned int pcie_dbi2_offset;
1107 struct dw_pcie_ep *ep;
1108 struct resource *res;
1109 struct dw_pcie *pci = imx6_pcie->pci;
1110 struct dw_pcie_rp *pp = &pci->pp;
1111 struct device *dev = pci->dev;
1112
1113 imx6_pcie_host_init(pp);
1114 ep = &pci->ep;
1115 ep->ops = &pcie_ep_ops;
1116
1117 switch (imx6_pcie->drvdata->variant) {
1118 case IMX8MQ_EP:
1119 case IMX8MM_EP:
1120 case IMX8MP_EP:
1121 pcie_dbi2_offset = SZ_1M;
1122 break;
1123 default:
1124 pcie_dbi2_offset = SZ_4K;
1125 break;
1126 }
1127 pci->dbi_base2 = pci->dbi_base + pcie_dbi2_offset;
1128 res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "addr_space");
1129 if (!res)
1130 return -EINVAL;
1131
1132 ep->phys_base = res->start;
1133 ep->addr_size = resource_size(res);
1134 ep->page_size = SZ_64K;
1135
1136 ret = dw_pcie_ep_init(ep);
1137 if (ret) {
1138 dev_err(dev, "failed to initialize endpoint\n");
1139 return ret;
1140 }
1141 /* Start LTSSM. */
1142 imx6_pcie_ltssm_enable(dev);
1143
1144 return 0;
1145 }
1146
imx6_pcie_pm_turnoff(struct imx6_pcie * imx6_pcie)1147 static void imx6_pcie_pm_turnoff(struct imx6_pcie *imx6_pcie)
1148 {
1149 struct device *dev = imx6_pcie->pci->dev;
1150
1151 /* Some variants have a turnoff reset in DT */
1152 if (imx6_pcie->turnoff_reset) {
1153 reset_control_assert(imx6_pcie->turnoff_reset);
1154 reset_control_deassert(imx6_pcie->turnoff_reset);
1155 goto pm_turnoff_sleep;
1156 }
1157
1158 /* Others poke directly at IOMUXC registers */
1159 switch (imx6_pcie->drvdata->variant) {
1160 case IMX6SX:
1161 case IMX6QP:
1162 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
1163 IMX6SX_GPR12_PCIE_PM_TURN_OFF,
1164 IMX6SX_GPR12_PCIE_PM_TURN_OFF);
1165 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
1166 IMX6SX_GPR12_PCIE_PM_TURN_OFF, 0);
1167 break;
1168 default:
1169 dev_err(dev, "PME_Turn_Off not implemented\n");
1170 return;
1171 }
1172
1173 /*
1174 * Components with an upstream port must respond to
1175 * PME_Turn_Off with PME_TO_Ack but we can't check.
1176 *
1177 * The standard recommends a 1-10ms timeout after which to
1178 * proceed anyway as if acks were received.
1179 */
1180 pm_turnoff_sleep:
1181 usleep_range(1000, 10000);
1182 }
1183
imx6_pcie_msi_save_restore(struct imx6_pcie * imx6_pcie,bool save)1184 static void imx6_pcie_msi_save_restore(struct imx6_pcie *imx6_pcie, bool save)
1185 {
1186 u8 offset;
1187 u16 val;
1188 struct dw_pcie *pci = imx6_pcie->pci;
1189
1190 if (pci_msi_enabled()) {
1191 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
1192 if (save) {
1193 val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
1194 imx6_pcie->msi_ctrl = val;
1195 } else {
1196 dw_pcie_dbi_ro_wr_en(pci);
1197 val = imx6_pcie->msi_ctrl;
1198 dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
1199 dw_pcie_dbi_ro_wr_dis(pci);
1200 }
1201 }
1202 }
1203
imx6_pcie_suspend_noirq(struct device * dev)1204 static int imx6_pcie_suspend_noirq(struct device *dev)
1205 {
1206 struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
1207 struct dw_pcie_rp *pp = &imx6_pcie->pci->pp;
1208
1209 if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_SUPPORTS_SUSPEND))
1210 return 0;
1211
1212 imx6_pcie_msi_save_restore(imx6_pcie, true);
1213 imx6_pcie_pm_turnoff(imx6_pcie);
1214 imx6_pcie_stop_link(imx6_pcie->pci);
1215 imx6_pcie_host_exit(pp);
1216
1217 return 0;
1218 }
1219
imx6_pcie_resume_noirq(struct device * dev)1220 static int imx6_pcie_resume_noirq(struct device *dev)
1221 {
1222 int ret;
1223 struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
1224 struct dw_pcie_rp *pp = &imx6_pcie->pci->pp;
1225
1226 if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_SUPPORTS_SUSPEND))
1227 return 0;
1228
1229 ret = imx6_pcie_host_init(pp);
1230 if (ret)
1231 return ret;
1232 imx6_pcie_msi_save_restore(imx6_pcie, false);
1233 dw_pcie_setup_rc(pp);
1234
1235 if (imx6_pcie->link_is_up)
1236 imx6_pcie_start_link(imx6_pcie->pci);
1237
1238 return 0;
1239 }
1240
1241 static const struct dev_pm_ops imx6_pcie_pm_ops = {
1242 NOIRQ_SYSTEM_SLEEP_PM_OPS(imx6_pcie_suspend_noirq,
1243 imx6_pcie_resume_noirq)
1244 };
1245
imx6_pcie_probe(struct platform_device * pdev)1246 static int imx6_pcie_probe(struct platform_device *pdev)
1247 {
1248 struct device *dev = &pdev->dev;
1249 struct dw_pcie *pci;
1250 struct imx6_pcie *imx6_pcie;
1251 struct device_node *np;
1252 struct resource *dbi_base;
1253 struct device_node *node = dev->of_node;
1254 int ret;
1255 u16 val;
1256
1257 imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL);
1258 if (!imx6_pcie)
1259 return -ENOMEM;
1260
1261 pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL);
1262 if (!pci)
1263 return -ENOMEM;
1264
1265 pci->dev = dev;
1266 pci->ops = &dw_pcie_ops;
1267 pci->pp.ops = &imx6_pcie_host_ops;
1268
1269 imx6_pcie->pci = pci;
1270 imx6_pcie->drvdata = of_device_get_match_data(dev);
1271
1272 /* Find the PHY if one is defined, only imx7d uses it */
1273 np = of_parse_phandle(node, "fsl,imx7d-pcie-phy", 0);
1274 if (np) {
1275 struct resource res;
1276
1277 ret = of_address_to_resource(np, 0, &res);
1278 if (ret) {
1279 dev_err(dev, "Unable to map PCIe PHY\n");
1280 return ret;
1281 }
1282 imx6_pcie->phy_base = devm_ioremap_resource(dev, &res);
1283 if (IS_ERR(imx6_pcie->phy_base))
1284 return PTR_ERR(imx6_pcie->phy_base);
1285 }
1286
1287 pci->dbi_base = devm_platform_get_and_ioremap_resource(pdev, 0, &dbi_base);
1288 if (IS_ERR(pci->dbi_base))
1289 return PTR_ERR(pci->dbi_base);
1290
1291 /* Fetch GPIOs */
1292 imx6_pcie->reset_gpio = of_get_named_gpio(node, "reset-gpio", 0);
1293 imx6_pcie->gpio_active_high = of_property_read_bool(node,
1294 "reset-gpio-active-high");
1295 if (gpio_is_valid(imx6_pcie->reset_gpio)) {
1296 ret = devm_gpio_request_one(dev, imx6_pcie->reset_gpio,
1297 imx6_pcie->gpio_active_high ?
1298 GPIOF_OUT_INIT_HIGH :
1299 GPIOF_OUT_INIT_LOW,
1300 "PCIe reset");
1301 if (ret) {
1302 dev_err(dev, "unable to get reset gpio\n");
1303 return ret;
1304 }
1305 } else if (imx6_pcie->reset_gpio == -EPROBE_DEFER) {
1306 return imx6_pcie->reset_gpio;
1307 }
1308
1309 /* Fetch clocks */
1310 imx6_pcie->pcie_bus = devm_clk_get(dev, "pcie_bus");
1311 if (IS_ERR(imx6_pcie->pcie_bus))
1312 return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_bus),
1313 "pcie_bus clock source missing or invalid\n");
1314
1315 imx6_pcie->pcie = devm_clk_get(dev, "pcie");
1316 if (IS_ERR(imx6_pcie->pcie))
1317 return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie),
1318 "pcie clock source missing or invalid\n");
1319
1320 switch (imx6_pcie->drvdata->variant) {
1321 case IMX6SX:
1322 imx6_pcie->pcie_inbound_axi = devm_clk_get(dev,
1323 "pcie_inbound_axi");
1324 if (IS_ERR(imx6_pcie->pcie_inbound_axi))
1325 return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_inbound_axi),
1326 "pcie_inbound_axi clock missing or invalid\n");
1327 break;
1328 case IMX8MQ:
1329 case IMX8MQ_EP:
1330 imx6_pcie->pcie_aux = devm_clk_get(dev, "pcie_aux");
1331 if (IS_ERR(imx6_pcie->pcie_aux))
1332 return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_aux),
1333 "pcie_aux clock source missing or invalid\n");
1334 fallthrough;
1335 case IMX7D:
1336 if (dbi_base->start == IMX8MQ_PCIE2_BASE_ADDR)
1337 imx6_pcie->controller_id = 1;
1338
1339 imx6_pcie->pciephy_reset = devm_reset_control_get_exclusive(dev,
1340 "pciephy");
1341 if (IS_ERR(imx6_pcie->pciephy_reset)) {
1342 dev_err(dev, "Failed to get PCIEPHY reset control\n");
1343 return PTR_ERR(imx6_pcie->pciephy_reset);
1344 }
1345
1346 imx6_pcie->apps_reset = devm_reset_control_get_exclusive(dev,
1347 "apps");
1348 if (IS_ERR(imx6_pcie->apps_reset)) {
1349 dev_err(dev, "Failed to get PCIE APPS reset control\n");
1350 return PTR_ERR(imx6_pcie->apps_reset);
1351 }
1352 break;
1353 case IMX8MM:
1354 case IMX8MM_EP:
1355 case IMX8MP:
1356 case IMX8MP_EP:
1357 imx6_pcie->pcie_aux = devm_clk_get(dev, "pcie_aux");
1358 if (IS_ERR(imx6_pcie->pcie_aux))
1359 return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_aux),
1360 "pcie_aux clock source missing or invalid\n");
1361 imx6_pcie->apps_reset = devm_reset_control_get_exclusive(dev,
1362 "apps");
1363 if (IS_ERR(imx6_pcie->apps_reset))
1364 return dev_err_probe(dev, PTR_ERR(imx6_pcie->apps_reset),
1365 "failed to get pcie apps reset control\n");
1366
1367 imx6_pcie->phy = devm_phy_get(dev, "pcie-phy");
1368 if (IS_ERR(imx6_pcie->phy))
1369 return dev_err_probe(dev, PTR_ERR(imx6_pcie->phy),
1370 "failed to get pcie phy\n");
1371
1372 break;
1373 default:
1374 break;
1375 }
1376 /* Don't fetch the pcie_phy clock, if it has abstract PHY driver */
1377 if (imx6_pcie->phy == NULL) {
1378 imx6_pcie->pcie_phy = devm_clk_get(dev, "pcie_phy");
1379 if (IS_ERR(imx6_pcie->pcie_phy))
1380 return dev_err_probe(dev, PTR_ERR(imx6_pcie->pcie_phy),
1381 "pcie_phy clock source missing or invalid\n");
1382 }
1383
1384
1385 /* Grab turnoff reset */
1386 imx6_pcie->turnoff_reset = devm_reset_control_get_optional_exclusive(dev, "turnoff");
1387 if (IS_ERR(imx6_pcie->turnoff_reset)) {
1388 dev_err(dev, "Failed to get TURNOFF reset control\n");
1389 return PTR_ERR(imx6_pcie->turnoff_reset);
1390 }
1391
1392 /* Grab GPR config register range */
1393 imx6_pcie->iomuxc_gpr =
1394 syscon_regmap_lookup_by_compatible(imx6_pcie->drvdata->gpr);
1395 if (IS_ERR(imx6_pcie->iomuxc_gpr)) {
1396 dev_err(dev, "unable to find iomuxc registers\n");
1397 return PTR_ERR(imx6_pcie->iomuxc_gpr);
1398 }
1399
1400 /* Grab PCIe PHY Tx Settings */
1401 if (of_property_read_u32(node, "fsl,tx-deemph-gen1",
1402 &imx6_pcie->tx_deemph_gen1))
1403 imx6_pcie->tx_deemph_gen1 = 0;
1404
1405 if (of_property_read_u32(node, "fsl,tx-deemph-gen2-3p5db",
1406 &imx6_pcie->tx_deemph_gen2_3p5db))
1407 imx6_pcie->tx_deemph_gen2_3p5db = 0;
1408
1409 if (of_property_read_u32(node, "fsl,tx-deemph-gen2-6db",
1410 &imx6_pcie->tx_deemph_gen2_6db))
1411 imx6_pcie->tx_deemph_gen2_6db = 20;
1412
1413 if (of_property_read_u32(node, "fsl,tx-swing-full",
1414 &imx6_pcie->tx_swing_full))
1415 imx6_pcie->tx_swing_full = 127;
1416
1417 if (of_property_read_u32(node, "fsl,tx-swing-low",
1418 &imx6_pcie->tx_swing_low))
1419 imx6_pcie->tx_swing_low = 127;
1420
1421 /* Limit link speed */
1422 pci->link_gen = 1;
1423 of_property_read_u32(node, "fsl,max-link-speed", &pci->link_gen);
1424
1425 imx6_pcie->vpcie = devm_regulator_get_optional(&pdev->dev, "vpcie");
1426 if (IS_ERR(imx6_pcie->vpcie)) {
1427 if (PTR_ERR(imx6_pcie->vpcie) != -ENODEV)
1428 return PTR_ERR(imx6_pcie->vpcie);
1429 imx6_pcie->vpcie = NULL;
1430 }
1431
1432 imx6_pcie->vph = devm_regulator_get_optional(&pdev->dev, "vph");
1433 if (IS_ERR(imx6_pcie->vph)) {
1434 if (PTR_ERR(imx6_pcie->vph) != -ENODEV)
1435 return PTR_ERR(imx6_pcie->vph);
1436 imx6_pcie->vph = NULL;
1437 }
1438
1439 platform_set_drvdata(pdev, imx6_pcie);
1440
1441 ret = imx6_pcie_attach_pd(dev);
1442 if (ret)
1443 return ret;
1444
1445 if (imx6_pcie->drvdata->mode == DW_PCIE_EP_TYPE) {
1446 ret = imx6_add_pcie_ep(imx6_pcie, pdev);
1447 if (ret < 0)
1448 return ret;
1449 } else {
1450 ret = dw_pcie_host_init(&pci->pp);
1451 if (ret < 0)
1452 return ret;
1453
1454 if (pci_msi_enabled()) {
1455 u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
1456
1457 val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
1458 val |= PCI_MSI_FLAGS_ENABLE;
1459 dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
1460 }
1461 }
1462
1463 return 0;
1464 }
1465
imx6_pcie_shutdown(struct platform_device * pdev)1466 static void imx6_pcie_shutdown(struct platform_device *pdev)
1467 {
1468 struct imx6_pcie *imx6_pcie = platform_get_drvdata(pdev);
1469
1470 /* bring down link, so bootloader gets clean state in case of reboot */
1471 imx6_pcie_assert_core_reset(imx6_pcie);
1472 }
1473
1474 static const struct imx6_pcie_drvdata drvdata[] = {
1475 [IMX6Q] = {
1476 .variant = IMX6Q,
1477 .flags = IMX6_PCIE_FLAG_IMX6_PHY |
1478 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE,
1479 .dbi_length = 0x200,
1480 .gpr = "fsl,imx6q-iomuxc-gpr",
1481 },
1482 [IMX6SX] = {
1483 .variant = IMX6SX,
1484 .flags = IMX6_PCIE_FLAG_IMX6_PHY |
1485 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE |
1486 IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
1487 .gpr = "fsl,imx6q-iomuxc-gpr",
1488 },
1489 [IMX6QP] = {
1490 .variant = IMX6QP,
1491 .flags = IMX6_PCIE_FLAG_IMX6_PHY |
1492 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE |
1493 IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
1494 .dbi_length = 0x200,
1495 .gpr = "fsl,imx6q-iomuxc-gpr",
1496 },
1497 [IMX7D] = {
1498 .variant = IMX7D,
1499 .flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
1500 .gpr = "fsl,imx7d-iomuxc-gpr",
1501 },
1502 [IMX8MQ] = {
1503 .variant = IMX8MQ,
1504 .gpr = "fsl,imx8mq-iomuxc-gpr",
1505 },
1506 [IMX8MM] = {
1507 .variant = IMX8MM,
1508 .flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
1509 .gpr = "fsl,imx8mm-iomuxc-gpr",
1510 },
1511 [IMX8MP] = {
1512 .variant = IMX8MP,
1513 .flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
1514 .gpr = "fsl,imx8mp-iomuxc-gpr",
1515 },
1516 [IMX8MQ_EP] = {
1517 .variant = IMX8MQ_EP,
1518 .mode = DW_PCIE_EP_TYPE,
1519 .gpr = "fsl,imx8mq-iomuxc-gpr",
1520 },
1521 [IMX8MM_EP] = {
1522 .variant = IMX8MM_EP,
1523 .mode = DW_PCIE_EP_TYPE,
1524 .gpr = "fsl,imx8mm-iomuxc-gpr",
1525 },
1526 [IMX8MP_EP] = {
1527 .variant = IMX8MP_EP,
1528 .mode = DW_PCIE_EP_TYPE,
1529 .gpr = "fsl,imx8mp-iomuxc-gpr",
1530 },
1531 };
1532
1533 static const struct of_device_id imx6_pcie_of_match[] = {
1534 { .compatible = "fsl,imx6q-pcie", .data = &drvdata[IMX6Q], },
1535 { .compatible = "fsl,imx6sx-pcie", .data = &drvdata[IMX6SX], },
1536 { .compatible = "fsl,imx6qp-pcie", .data = &drvdata[IMX6QP], },
1537 { .compatible = "fsl,imx7d-pcie", .data = &drvdata[IMX7D], },
1538 { .compatible = "fsl,imx8mq-pcie", .data = &drvdata[IMX8MQ], },
1539 { .compatible = "fsl,imx8mm-pcie", .data = &drvdata[IMX8MM], },
1540 { .compatible = "fsl,imx8mp-pcie", .data = &drvdata[IMX8MP], },
1541 { .compatible = "fsl,imx8mq-pcie-ep", .data = &drvdata[IMX8MQ_EP], },
1542 { .compatible = "fsl,imx8mm-pcie-ep", .data = &drvdata[IMX8MM_EP], },
1543 { .compatible = "fsl,imx8mp-pcie-ep", .data = &drvdata[IMX8MP_EP], },
1544 {},
1545 };
1546
1547 static struct platform_driver imx6_pcie_driver = {
1548 .driver = {
1549 .name = "imx6q-pcie",
1550 .of_match_table = imx6_pcie_of_match,
1551 .suppress_bind_attrs = true,
1552 .pm = &imx6_pcie_pm_ops,
1553 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
1554 },
1555 .probe = imx6_pcie_probe,
1556 .shutdown = imx6_pcie_shutdown,
1557 };
1558
imx6_pcie_quirk(struct pci_dev * dev)1559 static void imx6_pcie_quirk(struct pci_dev *dev)
1560 {
1561 struct pci_bus *bus = dev->bus;
1562 struct dw_pcie_rp *pp = bus->sysdata;
1563
1564 /* Bus parent is the PCI bridge, its parent is this platform driver */
1565 if (!bus->dev.parent || !bus->dev.parent->parent)
1566 return;
1567
1568 /* Make sure we only quirk devices associated with this driver */
1569 if (bus->dev.parent->parent->driver != &imx6_pcie_driver.driver)
1570 return;
1571
1572 if (pci_is_root_bus(bus)) {
1573 struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
1574 struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci);
1575
1576 /*
1577 * Limit config length to avoid the kernel reading beyond
1578 * the register set and causing an abort on i.MX 6Quad
1579 */
1580 if (imx6_pcie->drvdata->dbi_length) {
1581 dev->cfg_size = imx6_pcie->drvdata->dbi_length;
1582 dev_info(&dev->dev, "Limiting cfg_size to %d\n",
1583 dev->cfg_size);
1584 }
1585 }
1586 }
1587 DECLARE_PCI_FIXUP_CLASS_HEADER(PCI_VENDOR_ID_SYNOPSYS, 0xabcd,
1588 PCI_CLASS_BRIDGE_PCI, 8, imx6_pcie_quirk);
1589
imx6_pcie_init(void)1590 static int __init imx6_pcie_init(void)
1591 {
1592 #ifdef CONFIG_ARM
1593 struct device_node *np;
1594
1595 np = of_find_matching_node(NULL, imx6_pcie_of_match);
1596 if (!np)
1597 return -ENODEV;
1598 of_node_put(np);
1599
1600 /*
1601 * Since probe() can be deferred we need to make sure that
1602 * hook_fault_code is not called after __init memory is freed
1603 * by kernel and since imx6q_pcie_abort_handler() is a no-op,
1604 * we can install the handler here without risking it
1605 * accessing some uninitialized driver state.
1606 */
1607 hook_fault_code(8, imx6q_pcie_abort_handler, SIGBUS, 0,
1608 "external abort on non-linefetch");
1609 #endif
1610
1611 return platform_driver_register(&imx6_pcie_driver);
1612 }
1613 device_initcall(imx6_pcie_init);
1614