1 // SPDX-License-Identifier: GPL-2.0
3 * PCIe host controller driver for Freescale i.MX6 SoCs
5 * Copyright (C) 2013 Kosagi
6 * https://www.kosagi.com
8 * Author: Sean Cross <xobs@kosagi.com>
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_gpio.h>
21 #include <linux/of_device.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/pm_domain.h>
33 #include <linux/pm_runtime.h>
35 #include "pcie-designware.h"
37 #define IMX8MQ_GPR_PCIE_REF_USE_PAD BIT(9)
38 #define IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN BIT(10)
39 #define IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE BIT(11)
40 #define IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE GENMASK(11, 8)
41 #define IMX8MQ_PCIE2_BASE_ADDR 0x33c00000
43 #define to_imx6_pcie(x) dev_get_drvdata((x)->dev)
45 enum imx6_pcie_variants {
53 #define IMX6_PCIE_FLAG_IMX6_PHY BIT(0)
54 #define IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE BIT(1)
55 #define IMX6_PCIE_FLAG_SUPPORTS_SUSPEND BIT(2)
57 struct imx6_pcie_drvdata {
58 enum imx6_pcie_variants variant;
66 bool gpio_active_high;
69 struct clk *pcie_inbound_axi;
72 struct regmap *iomuxc_gpr;
74 struct reset_control *pciephy_reset;
75 struct reset_control *apps_reset;
76 struct reset_control *turnoff_reset;
78 u32 tx_deemph_gen2_3p5db;
79 u32 tx_deemph_gen2_6db;
83 struct regulator *vpcie;
84 void __iomem *phy_base;
86 /* power domain for pcie */
87 struct device *pd_pcie;
88 /* power domain for pcie phy */
89 struct device *pd_pcie_phy;
90 const struct imx6_pcie_drvdata *drvdata;
93 /* Parameters for the waiting for PCIe PHY PLL to lock on i.MX7 */
94 #define PHY_PLL_LOCK_WAIT_USLEEP_MAX 200
95 #define PHY_PLL_LOCK_WAIT_TIMEOUT (2000 * PHY_PLL_LOCK_WAIT_USLEEP_MAX)
97 /* PCIe Port Logic registers (memory-mapped) */
98 #define PL_OFFSET 0x700
100 #define PCIE_PHY_CTRL (PL_OFFSET + 0x114)
101 #define PCIE_PHY_CTRL_DATA(x) FIELD_PREP(GENMASK(15, 0), (x))
102 #define PCIE_PHY_CTRL_CAP_ADR BIT(16)
103 #define PCIE_PHY_CTRL_CAP_DAT BIT(17)
104 #define PCIE_PHY_CTRL_WR BIT(18)
105 #define PCIE_PHY_CTRL_RD BIT(19)
107 #define PCIE_PHY_STAT (PL_OFFSET + 0x110)
108 #define PCIE_PHY_STAT_ACK BIT(16)
110 /* PHY registers (not memory-mapped) */
111 #define PCIE_PHY_ATEOVRD 0x10
112 #define PCIE_PHY_ATEOVRD_EN BIT(2)
113 #define PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT 0
114 #define PCIE_PHY_ATEOVRD_REF_CLKDIV_MASK 0x1
116 #define PCIE_PHY_MPLL_OVRD_IN_LO 0x11
117 #define PCIE_PHY_MPLL_MULTIPLIER_SHIFT 2
118 #define PCIE_PHY_MPLL_MULTIPLIER_MASK 0x7f
119 #define PCIE_PHY_MPLL_MULTIPLIER_OVRD BIT(9)
121 #define PCIE_PHY_RX_ASIC_OUT 0x100D
122 #define PCIE_PHY_RX_ASIC_OUT_VALID (1 << 0)
124 /* iMX7 PCIe PHY registers */
125 #define PCIE_PHY_CMN_REG4 0x14
126 /* These are probably the bits that *aren't* DCC_FB_EN */
127 #define PCIE_PHY_CMN_REG4_DCC_FB_EN 0x29
129 #define PCIE_PHY_CMN_REG15 0x54
130 #define PCIE_PHY_CMN_REG15_DLY_4 BIT(2)
131 #define PCIE_PHY_CMN_REG15_PLL_PD BIT(5)
132 #define PCIE_PHY_CMN_REG15_OVRD_PLL_PD BIT(7)
134 #define PCIE_PHY_CMN_REG24 0x90
135 #define PCIE_PHY_CMN_REG24_RX_EQ BIT(6)
136 #define PCIE_PHY_CMN_REG24_RX_EQ_SEL BIT(3)
138 #define PCIE_PHY_CMN_REG26 0x98
139 #define PCIE_PHY_CMN_REG26_ATT_MODE 0xBC
141 #define PHY_RX_OVRD_IN_LO 0x1005
142 #define PHY_RX_OVRD_IN_LO_RX_DATA_EN BIT(5)
143 #define PHY_RX_OVRD_IN_LO_RX_PLL_EN BIT(3)
145 static int pcie_phy_poll_ack(struct imx6_pcie *imx6_pcie, bool exp_val)
147 struct dw_pcie *pci = imx6_pcie->pci;
149 u32 max_iterations = 10;
150 u32 wait_counter = 0;
153 val = dw_pcie_readl_dbi(pci, PCIE_PHY_STAT) &
161 } while (wait_counter < max_iterations);
166 static int pcie_phy_wait_ack(struct imx6_pcie *imx6_pcie, int addr)
168 struct dw_pcie *pci = imx6_pcie->pci;
172 val = PCIE_PHY_CTRL_DATA(addr);
173 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
175 val |= PCIE_PHY_CTRL_CAP_ADR;
176 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
178 ret = pcie_phy_poll_ack(imx6_pcie, true);
182 val = PCIE_PHY_CTRL_DATA(addr);
183 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
185 return pcie_phy_poll_ack(imx6_pcie, false);
188 /* Read from the 16-bit PCIe PHY control registers (not memory-mapped) */
189 static int pcie_phy_read(struct imx6_pcie *imx6_pcie, int addr, u16 *data)
191 struct dw_pcie *pci = imx6_pcie->pci;
195 ret = pcie_phy_wait_ack(imx6_pcie, addr);
199 /* assert Read signal */
200 phy_ctl = PCIE_PHY_CTRL_RD;
201 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, phy_ctl);
203 ret = pcie_phy_poll_ack(imx6_pcie, true);
207 *data = dw_pcie_readl_dbi(pci, PCIE_PHY_STAT);
209 /* deassert Read signal */
210 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, 0x00);
212 return pcie_phy_poll_ack(imx6_pcie, false);
215 static int pcie_phy_write(struct imx6_pcie *imx6_pcie, int addr, u16 data)
217 struct dw_pcie *pci = imx6_pcie->pci;
223 ret = pcie_phy_wait_ack(imx6_pcie, addr);
227 var = PCIE_PHY_CTRL_DATA(data);
228 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
231 var |= PCIE_PHY_CTRL_CAP_DAT;
232 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
234 ret = pcie_phy_poll_ack(imx6_pcie, true);
238 /* deassert cap data */
239 var = PCIE_PHY_CTRL_DATA(data);
240 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
242 /* wait for ack de-assertion */
243 ret = pcie_phy_poll_ack(imx6_pcie, false);
247 /* assert wr signal */
248 var = PCIE_PHY_CTRL_WR;
249 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
252 ret = pcie_phy_poll_ack(imx6_pcie, true);
256 /* deassert wr signal */
257 var = PCIE_PHY_CTRL_DATA(data);
258 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
260 /* wait for ack de-assertion */
261 ret = pcie_phy_poll_ack(imx6_pcie, false);
265 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, 0x0);
270 static void imx6_pcie_reset_phy(struct imx6_pcie *imx6_pcie)
274 if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_IMX6_PHY))
277 pcie_phy_read(imx6_pcie, PHY_RX_OVRD_IN_LO, &tmp);
278 tmp |= (PHY_RX_OVRD_IN_LO_RX_DATA_EN |
279 PHY_RX_OVRD_IN_LO_RX_PLL_EN);
280 pcie_phy_write(imx6_pcie, PHY_RX_OVRD_IN_LO, tmp);
282 usleep_range(2000, 3000);
284 pcie_phy_read(imx6_pcie, PHY_RX_OVRD_IN_LO, &tmp);
285 tmp &= ~(PHY_RX_OVRD_IN_LO_RX_DATA_EN |
286 PHY_RX_OVRD_IN_LO_RX_PLL_EN);
287 pcie_phy_write(imx6_pcie, PHY_RX_OVRD_IN_LO, tmp);
291 /* Added for PCI abort handling */
292 static int imx6q_pcie_abort_handler(unsigned long addr,
293 unsigned int fsr, struct pt_regs *regs)
295 unsigned long pc = instruction_pointer(regs);
296 unsigned long instr = *(unsigned long *)pc;
297 int reg = (instr >> 12) & 15;
300 * If the instruction being executed was a read,
301 * make it look like it read all-ones.
303 if ((instr & 0x0c100000) == 0x04100000) {
306 if (instr & 0x00400000)
311 regs->uregs[reg] = val;
316 if ((instr & 0x0e100090) == 0x00100090) {
317 regs->uregs[reg] = -1;
326 static int imx6_pcie_attach_pd(struct device *dev)
328 struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
329 struct device_link *link;
331 /* Do nothing when in a single power domain */
335 imx6_pcie->pd_pcie = dev_pm_domain_attach_by_name(dev, "pcie");
336 if (IS_ERR(imx6_pcie->pd_pcie))
337 return PTR_ERR(imx6_pcie->pd_pcie);
338 /* Do nothing when power domain missing */
339 if (!imx6_pcie->pd_pcie)
341 link = device_link_add(dev, imx6_pcie->pd_pcie,
346 dev_err(dev, "Failed to add device_link to pcie pd.\n");
350 imx6_pcie->pd_pcie_phy = dev_pm_domain_attach_by_name(dev, "pcie_phy");
351 if (IS_ERR(imx6_pcie->pd_pcie_phy))
352 return PTR_ERR(imx6_pcie->pd_pcie_phy);
354 link = device_link_add(dev, imx6_pcie->pd_pcie_phy,
359 dev_err(dev, "Failed to add device_link to pcie_phy pd.\n");
366 static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
368 struct device *dev = imx6_pcie->pci->dev;
370 switch (imx6_pcie->drvdata->variant) {
373 reset_control_assert(imx6_pcie->pciephy_reset);
374 reset_control_assert(imx6_pcie->apps_reset);
377 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
378 IMX6SX_GPR12_PCIE_TEST_POWERDOWN,
379 IMX6SX_GPR12_PCIE_TEST_POWERDOWN);
380 /* Force PCIe PHY reset */
381 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5,
382 IMX6SX_GPR5_PCIE_BTNRST_RESET,
383 IMX6SX_GPR5_PCIE_BTNRST_RESET);
386 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
387 IMX6Q_GPR1_PCIE_SW_RST,
388 IMX6Q_GPR1_PCIE_SW_RST);
391 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
392 IMX6Q_GPR1_PCIE_TEST_PD, 1 << 18);
393 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
394 IMX6Q_GPR1_PCIE_REF_CLK_EN, 0 << 16);
398 if (imx6_pcie->vpcie && regulator_is_enabled(imx6_pcie->vpcie) > 0) {
399 int ret = regulator_disable(imx6_pcie->vpcie);
402 dev_err(dev, "failed to disable vpcie regulator: %d\n",
407 static unsigned int imx6_pcie_grp_offset(const struct imx6_pcie *imx6_pcie)
409 WARN_ON(imx6_pcie->drvdata->variant != IMX8MQ);
410 return imx6_pcie->controller_id == 1 ? IOMUXC_GPR16 : IOMUXC_GPR14;
413 static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie)
415 struct dw_pcie *pci = imx6_pcie->pci;
416 struct device *dev = pci->dev;
420 switch (imx6_pcie->drvdata->variant) {
422 ret = clk_prepare_enable(imx6_pcie->pcie_inbound_axi);
424 dev_err(dev, "unable to enable pcie_axi clock\n");
428 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
429 IMX6SX_GPR12_PCIE_TEST_POWERDOWN, 0);
431 case IMX6QP: /* FALLTHROUGH */
433 /* power up core phy and enable ref clock */
434 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
435 IMX6Q_GPR1_PCIE_TEST_PD, 0 << 18);
437 * the async reset input need ref clock to sync internally,
438 * when the ref clock comes after reset, internal synced
439 * reset time is too short, cannot meet the requirement.
440 * add one ~10us delay here.
442 usleep_range(10, 100);
443 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
444 IMX6Q_GPR1_PCIE_REF_CLK_EN, 1 << 16);
449 ret = clk_prepare_enable(imx6_pcie->pcie_aux);
451 dev_err(dev, "unable to enable pcie_aux clock\n");
455 offset = imx6_pcie_grp_offset(imx6_pcie);
457 * Set the over ride low and enabled
458 * make sure that REF_CLK is turned on.
460 regmap_update_bits(imx6_pcie->iomuxc_gpr, offset,
461 IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE,
463 regmap_update_bits(imx6_pcie->iomuxc_gpr, offset,
464 IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN,
465 IMX8MQ_GPR_PCIE_CLK_REQ_OVERRIDE_EN);
472 static void imx7d_pcie_wait_for_phy_pll_lock(struct imx6_pcie *imx6_pcie)
475 struct device *dev = imx6_pcie->pci->dev;
477 if (regmap_read_poll_timeout(imx6_pcie->iomuxc_gpr,
479 val & IMX7D_GPR22_PCIE_PHY_PLL_LOCKED,
480 PHY_PLL_LOCK_WAIT_USLEEP_MAX,
481 PHY_PLL_LOCK_WAIT_TIMEOUT))
482 dev_err(dev, "PCIe PLL lock timeout\n");
485 static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
487 struct dw_pcie *pci = imx6_pcie->pci;
488 struct device *dev = pci->dev;
491 if (imx6_pcie->vpcie && !regulator_is_enabled(imx6_pcie->vpcie)) {
492 ret = regulator_enable(imx6_pcie->vpcie);
494 dev_err(dev, "failed to enable vpcie regulator: %d\n",
500 ret = clk_prepare_enable(imx6_pcie->pcie_phy);
502 dev_err(dev, "unable to enable pcie_phy clock\n");
506 ret = clk_prepare_enable(imx6_pcie->pcie_bus);
508 dev_err(dev, "unable to enable pcie_bus clock\n");
512 ret = clk_prepare_enable(imx6_pcie->pcie);
514 dev_err(dev, "unable to enable pcie clock\n");
518 ret = imx6_pcie_enable_ref_clk(imx6_pcie);
520 dev_err(dev, "unable to enable pcie ref clock\n");
524 /* allow the clocks to stabilize */
525 usleep_range(200, 500);
527 /* Some boards don't have PCIe reset GPIO. */
528 if (gpio_is_valid(imx6_pcie->reset_gpio)) {
529 gpio_set_value_cansleep(imx6_pcie->reset_gpio,
530 imx6_pcie->gpio_active_high);
532 gpio_set_value_cansleep(imx6_pcie->reset_gpio,
533 !imx6_pcie->gpio_active_high);
536 switch (imx6_pcie->drvdata->variant) {
538 reset_control_deassert(imx6_pcie->pciephy_reset);
541 reset_control_deassert(imx6_pcie->pciephy_reset);
543 /* Workaround for ERR010728, failure of PCI-e PLL VCO to
544 * oscillate, especially when cold. This turns off "Duty-cycle
545 * Corrector" and other mysterious undocumented things.
547 if (likely(imx6_pcie->phy_base)) {
548 /* De-assert DCC_FB_EN */
549 writel(PCIE_PHY_CMN_REG4_DCC_FB_EN,
550 imx6_pcie->phy_base + PCIE_PHY_CMN_REG4);
551 /* Assert RX_EQS and RX_EQS_SEL */
552 writel(PCIE_PHY_CMN_REG24_RX_EQ_SEL
553 | PCIE_PHY_CMN_REG24_RX_EQ,
554 imx6_pcie->phy_base + PCIE_PHY_CMN_REG24);
555 /* Assert ATT_MODE */
556 writel(PCIE_PHY_CMN_REG26_ATT_MODE,
557 imx6_pcie->phy_base + PCIE_PHY_CMN_REG26);
559 dev_warn(dev, "Unable to apply ERR010728 workaround. DT missing fsl,imx7d-pcie-phy phandle ?\n");
562 imx7d_pcie_wait_for_phy_pll_lock(imx6_pcie);
565 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5,
566 IMX6SX_GPR5_PCIE_BTNRST_RESET, 0);
569 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
570 IMX6Q_GPR1_PCIE_SW_RST, 0);
572 usleep_range(200, 500);
574 case IMX6Q: /* Nothing to do */
581 clk_disable_unprepare(imx6_pcie->pcie);
583 clk_disable_unprepare(imx6_pcie->pcie_bus);
585 clk_disable_unprepare(imx6_pcie->pcie_phy);
587 if (imx6_pcie->vpcie && regulator_is_enabled(imx6_pcie->vpcie) > 0) {
588 ret = regulator_disable(imx6_pcie->vpcie);
590 dev_err(dev, "failed to disable vpcie regulator: %d\n",
595 static void imx6_pcie_configure_type(struct imx6_pcie *imx6_pcie)
597 unsigned int mask, val;
599 if (imx6_pcie->drvdata->variant == IMX8MQ &&
600 imx6_pcie->controller_id == 1) {
601 mask = IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE;
602 val = FIELD_PREP(IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE,
603 PCI_EXP_TYPE_ROOT_PORT);
605 mask = IMX6Q_GPR12_DEVICE_TYPE;
606 val = FIELD_PREP(IMX6Q_GPR12_DEVICE_TYPE,
607 PCI_EXP_TYPE_ROOT_PORT);
610 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, mask, val);
613 static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie)
615 switch (imx6_pcie->drvdata->variant) {
618 * TODO: Currently this code assumes external
619 * oscillator is being used
621 regmap_update_bits(imx6_pcie->iomuxc_gpr,
622 imx6_pcie_grp_offset(imx6_pcie),
623 IMX8MQ_GPR_PCIE_REF_USE_PAD,
624 IMX8MQ_GPR_PCIE_REF_USE_PAD);
627 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
628 IMX7D_GPR12_PCIE_PHY_REFCLK_SEL, 0);
631 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
632 IMX6SX_GPR12_PCIE_RX_EQ_MASK,
633 IMX6SX_GPR12_PCIE_RX_EQ_2);
636 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
637 IMX6Q_GPR12_PCIE_CTL_2, 0 << 10);
639 /* configure constant input signal to the pcie ctrl and phy */
640 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
641 IMX6Q_GPR12_LOS_LEVEL, 9 << 4);
643 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
644 IMX6Q_GPR8_TX_DEEMPH_GEN1,
645 imx6_pcie->tx_deemph_gen1 << 0);
646 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
647 IMX6Q_GPR8_TX_DEEMPH_GEN2_3P5DB,
648 imx6_pcie->tx_deemph_gen2_3p5db << 6);
649 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
650 IMX6Q_GPR8_TX_DEEMPH_GEN2_6DB,
651 imx6_pcie->tx_deemph_gen2_6db << 12);
652 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
653 IMX6Q_GPR8_TX_SWING_FULL,
654 imx6_pcie->tx_swing_full << 18);
655 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
656 IMX6Q_GPR8_TX_SWING_LOW,
657 imx6_pcie->tx_swing_low << 25);
661 imx6_pcie_configure_type(imx6_pcie);
664 static int imx6_setup_phy_mpll(struct imx6_pcie *imx6_pcie)
666 unsigned long phy_rate = clk_get_rate(imx6_pcie->pcie_phy);
670 if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_IMX6_PHY))
676 * The default settings of the MPLL are for a 125MHz input
677 * clock, so no need to reconfigure anything in that case.
689 dev_err(imx6_pcie->pci->dev,
690 "Unsupported PHY reference clock rate %lu\n", phy_rate);
694 pcie_phy_read(imx6_pcie, PCIE_PHY_MPLL_OVRD_IN_LO, &val);
695 val &= ~(PCIE_PHY_MPLL_MULTIPLIER_MASK <<
696 PCIE_PHY_MPLL_MULTIPLIER_SHIFT);
697 val |= mult << PCIE_PHY_MPLL_MULTIPLIER_SHIFT;
698 val |= PCIE_PHY_MPLL_MULTIPLIER_OVRD;
699 pcie_phy_write(imx6_pcie, PCIE_PHY_MPLL_OVRD_IN_LO, val);
701 pcie_phy_read(imx6_pcie, PCIE_PHY_ATEOVRD, &val);
702 val &= ~(PCIE_PHY_ATEOVRD_REF_CLKDIV_MASK <<
703 PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT);
704 val |= div << PCIE_PHY_ATEOVRD_REF_CLKDIV_SHIFT;
705 val |= PCIE_PHY_ATEOVRD_EN;
706 pcie_phy_write(imx6_pcie, PCIE_PHY_ATEOVRD, val);
711 static int imx6_pcie_wait_for_speed_change(struct imx6_pcie *imx6_pcie)
713 struct dw_pcie *pci = imx6_pcie->pci;
714 struct device *dev = pci->dev;
716 unsigned int retries;
718 for (retries = 0; retries < 200; retries++) {
719 tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
720 /* Test if the speed change finished. */
721 if (!(tmp & PORT_LOGIC_SPEED_CHANGE))
723 usleep_range(100, 1000);
726 dev_err(dev, "Speed change timeout\n");
730 static void imx6_pcie_ltssm_enable(struct device *dev)
732 struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
734 switch (imx6_pcie->drvdata->variant) {
738 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
739 IMX6Q_GPR12_PCIE_CTL_2,
740 IMX6Q_GPR12_PCIE_CTL_2);
744 reset_control_deassert(imx6_pcie->apps_reset);
749 static int imx6_pcie_establish_link(struct imx6_pcie *imx6_pcie)
751 struct dw_pcie *pci = imx6_pcie->pci;
752 struct device *dev = pci->dev;
753 u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_EXP);
758 * Force Gen1 operation when starting the link. In case the link is
759 * started in Gen2 mode, there is a possibility the devices on the
760 * bus will not be detected at all. This happens with PCIe switches.
762 tmp = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP);
763 tmp &= ~PCI_EXP_LNKCAP_SLS;
764 tmp |= PCI_EXP_LNKCAP_SLS_2_5GB;
765 dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, tmp);
768 imx6_pcie_ltssm_enable(dev);
770 ret = dw_pcie_wait_for_link(pci);
774 if (imx6_pcie->link_gen == 2) {
775 /* Allow Gen2 mode after the link is up. */
776 tmp = dw_pcie_readl_dbi(pci, offset + PCI_EXP_LNKCAP);
777 tmp &= ~PCI_EXP_LNKCAP_SLS;
778 tmp |= PCI_EXP_LNKCAP_SLS_5_0GB;
779 dw_pcie_writel_dbi(pci, offset + PCI_EXP_LNKCAP, tmp);
782 * Start Directed Speed Change so the best possible
783 * speed both link partners support can be negotiated.
785 tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
786 tmp |= PORT_LOGIC_SPEED_CHANGE;
787 dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, tmp);
789 if (imx6_pcie->drvdata->flags &
790 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE) {
792 * On i.MX7, DIRECT_SPEED_CHANGE behaves differently
793 * from i.MX6 family when no link speed transition
794 * occurs and we go Gen1 -> yep, Gen1. The difference
795 * is that, in such case, it will not be cleared by HW
796 * which will cause the following code to report false
800 ret = imx6_pcie_wait_for_speed_change(imx6_pcie);
802 dev_err(dev, "Failed to bring link up!\n");
807 /* Make sure link training is finished as well! */
808 ret = dw_pcie_wait_for_link(pci);
810 dev_err(dev, "Failed to bring link up!\n");
814 dev_info(dev, "Link: Gen2 disabled\n");
817 tmp = dw_pcie_readw_dbi(pci, offset + PCI_EXP_LNKSTA);
818 dev_info(dev, "Link up, Gen%i\n", tmp & PCI_EXP_LNKSTA_CLS);
822 dev_dbg(dev, "PHY DEBUG_R0=0x%08x DEBUG_R1=0x%08x\n",
823 dw_pcie_readl_dbi(pci, PCIE_PORT_DEBUG0),
824 dw_pcie_readl_dbi(pci, PCIE_PORT_DEBUG1));
825 imx6_pcie_reset_phy(imx6_pcie);
829 static int imx6_pcie_host_init(struct pcie_port *pp)
831 struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
832 struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci);
834 imx6_pcie_assert_core_reset(imx6_pcie);
835 imx6_pcie_init_phy(imx6_pcie);
836 imx6_pcie_deassert_core_reset(imx6_pcie);
837 imx6_setup_phy_mpll(imx6_pcie);
838 dw_pcie_setup_rc(pp);
839 imx6_pcie_establish_link(imx6_pcie);
840 dw_pcie_msi_init(pp);
845 static const struct dw_pcie_host_ops imx6_pcie_host_ops = {
846 .host_init = imx6_pcie_host_init,
849 static int imx6_add_pcie_port(struct imx6_pcie *imx6_pcie,
850 struct platform_device *pdev)
852 struct dw_pcie *pci = imx6_pcie->pci;
853 struct pcie_port *pp = &pci->pp;
854 struct device *dev = &pdev->dev;
857 if (IS_ENABLED(CONFIG_PCI_MSI)) {
858 pp->msi_irq = platform_get_irq_byname(pdev, "msi");
863 pp->ops = &imx6_pcie_host_ops;
865 ret = dw_pcie_host_init(pp);
867 dev_err(dev, "failed to initialize host\n");
874 static const struct dw_pcie_ops dw_pcie_ops = {
875 /* No special ops needed, but pcie-designware still expects this struct */
878 #ifdef CONFIG_PM_SLEEP
879 static void imx6_pcie_ltssm_disable(struct device *dev)
881 struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
883 switch (imx6_pcie->drvdata->variant) {
886 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
887 IMX6Q_GPR12_PCIE_CTL_2, 0);
890 reset_control_assert(imx6_pcie->apps_reset);
893 dev_err(dev, "ltssm_disable not supported\n");
897 static void imx6_pcie_pm_turnoff(struct imx6_pcie *imx6_pcie)
899 struct device *dev = imx6_pcie->pci->dev;
901 /* Some variants have a turnoff reset in DT */
902 if (imx6_pcie->turnoff_reset) {
903 reset_control_assert(imx6_pcie->turnoff_reset);
904 reset_control_deassert(imx6_pcie->turnoff_reset);
905 goto pm_turnoff_sleep;
908 /* Others poke directly at IOMUXC registers */
909 switch (imx6_pcie->drvdata->variant) {
911 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
912 IMX6SX_GPR12_PCIE_PM_TURN_OFF,
913 IMX6SX_GPR12_PCIE_PM_TURN_OFF);
914 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
915 IMX6SX_GPR12_PCIE_PM_TURN_OFF, 0);
918 dev_err(dev, "PME_Turn_Off not implemented\n");
923 * Components with an upstream port must respond to
924 * PME_Turn_Off with PME_TO_Ack but we can't check.
926 * The standard recommends a 1-10ms timeout after which to
927 * proceed anyway as if acks were received.
930 usleep_range(1000, 10000);
933 static void imx6_pcie_clk_disable(struct imx6_pcie *imx6_pcie)
935 clk_disable_unprepare(imx6_pcie->pcie);
936 clk_disable_unprepare(imx6_pcie->pcie_phy);
937 clk_disable_unprepare(imx6_pcie->pcie_bus);
939 switch (imx6_pcie->drvdata->variant) {
941 clk_disable_unprepare(imx6_pcie->pcie_inbound_axi);
944 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
945 IMX7D_GPR12_PCIE_PHY_REFCLK_SEL,
946 IMX7D_GPR12_PCIE_PHY_REFCLK_SEL);
949 clk_disable_unprepare(imx6_pcie->pcie_aux);
956 static int imx6_pcie_suspend_noirq(struct device *dev)
958 struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
960 if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_SUPPORTS_SUSPEND))
963 imx6_pcie_pm_turnoff(imx6_pcie);
964 imx6_pcie_clk_disable(imx6_pcie);
965 imx6_pcie_ltssm_disable(dev);
970 static int imx6_pcie_resume_noirq(struct device *dev)
973 struct imx6_pcie *imx6_pcie = dev_get_drvdata(dev);
974 struct pcie_port *pp = &imx6_pcie->pci->pp;
976 if (!(imx6_pcie->drvdata->flags & IMX6_PCIE_FLAG_SUPPORTS_SUSPEND))
979 imx6_pcie_assert_core_reset(imx6_pcie);
980 imx6_pcie_init_phy(imx6_pcie);
981 imx6_pcie_deassert_core_reset(imx6_pcie);
982 dw_pcie_setup_rc(pp);
984 ret = imx6_pcie_establish_link(imx6_pcie);
986 dev_info(dev, "pcie link is down after resume.\n");
992 static const struct dev_pm_ops imx6_pcie_pm_ops = {
993 SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx6_pcie_suspend_noirq,
994 imx6_pcie_resume_noirq)
997 static int imx6_pcie_probe(struct platform_device *pdev)
999 struct device *dev = &pdev->dev;
1000 struct dw_pcie *pci;
1001 struct imx6_pcie *imx6_pcie;
1002 struct device_node *np;
1003 struct resource *dbi_base;
1004 struct device_node *node = dev->of_node;
1008 imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL);
1012 pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL);
1017 pci->ops = &dw_pcie_ops;
1019 imx6_pcie->pci = pci;
1020 imx6_pcie->drvdata = of_device_get_match_data(dev);
1022 /* Find the PHY if one is defined, only imx7d uses it */
1023 np = of_parse_phandle(node, "fsl,imx7d-pcie-phy", 0);
1025 struct resource res;
1027 ret = of_address_to_resource(np, 0, &res);
1029 dev_err(dev, "Unable to map PCIe PHY\n");
1032 imx6_pcie->phy_base = devm_ioremap_resource(dev, &res);
1033 if (IS_ERR(imx6_pcie->phy_base)) {
1034 dev_err(dev, "Unable to map PCIe PHY\n");
1035 return PTR_ERR(imx6_pcie->phy_base);
1039 dbi_base = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1040 pci->dbi_base = devm_ioremap_resource(dev, dbi_base);
1041 if (IS_ERR(pci->dbi_base))
1042 return PTR_ERR(pci->dbi_base);
1045 imx6_pcie->reset_gpio = of_get_named_gpio(node, "reset-gpio", 0);
1046 imx6_pcie->gpio_active_high = of_property_read_bool(node,
1047 "reset-gpio-active-high");
1048 if (gpio_is_valid(imx6_pcie->reset_gpio)) {
1049 ret = devm_gpio_request_one(dev, imx6_pcie->reset_gpio,
1050 imx6_pcie->gpio_active_high ?
1051 GPIOF_OUT_INIT_HIGH :
1055 dev_err(dev, "unable to get reset gpio\n");
1058 } else if (imx6_pcie->reset_gpio == -EPROBE_DEFER) {
1059 return imx6_pcie->reset_gpio;
1063 imx6_pcie->pcie_phy = devm_clk_get(dev, "pcie_phy");
1064 if (IS_ERR(imx6_pcie->pcie_phy)) {
1065 dev_err(dev, "pcie_phy clock source missing or invalid\n");
1066 return PTR_ERR(imx6_pcie->pcie_phy);
1069 imx6_pcie->pcie_bus = devm_clk_get(dev, "pcie_bus");
1070 if (IS_ERR(imx6_pcie->pcie_bus)) {
1071 dev_err(dev, "pcie_bus clock source missing or invalid\n");
1072 return PTR_ERR(imx6_pcie->pcie_bus);
1075 imx6_pcie->pcie = devm_clk_get(dev, "pcie");
1076 if (IS_ERR(imx6_pcie->pcie)) {
1077 dev_err(dev, "pcie clock source missing or invalid\n");
1078 return PTR_ERR(imx6_pcie->pcie);
1081 switch (imx6_pcie->drvdata->variant) {
1083 imx6_pcie->pcie_inbound_axi = devm_clk_get(dev,
1084 "pcie_inbound_axi");
1085 if (IS_ERR(imx6_pcie->pcie_inbound_axi)) {
1086 dev_err(dev, "pcie_inbound_axi clock missing or invalid\n");
1087 return PTR_ERR(imx6_pcie->pcie_inbound_axi);
1091 imx6_pcie->pcie_aux = devm_clk_get(dev, "pcie_aux");
1092 if (IS_ERR(imx6_pcie->pcie_aux)) {
1093 dev_err(dev, "pcie_aux clock source missing or invalid\n");
1094 return PTR_ERR(imx6_pcie->pcie_aux);
1098 if (dbi_base->start == IMX8MQ_PCIE2_BASE_ADDR)
1099 imx6_pcie->controller_id = 1;
1101 imx6_pcie->pciephy_reset = devm_reset_control_get_exclusive(dev,
1103 if (IS_ERR(imx6_pcie->pciephy_reset)) {
1104 dev_err(dev, "Failed to get PCIEPHY reset control\n");
1105 return PTR_ERR(imx6_pcie->pciephy_reset);
1108 imx6_pcie->apps_reset = devm_reset_control_get_exclusive(dev,
1110 if (IS_ERR(imx6_pcie->apps_reset)) {
1111 dev_err(dev, "Failed to get PCIE APPS reset control\n");
1112 return PTR_ERR(imx6_pcie->apps_reset);
1119 /* Grab turnoff reset */
1120 imx6_pcie->turnoff_reset = devm_reset_control_get_optional_exclusive(dev, "turnoff");
1121 if (IS_ERR(imx6_pcie->turnoff_reset)) {
1122 dev_err(dev, "Failed to get TURNOFF reset control\n");
1123 return PTR_ERR(imx6_pcie->turnoff_reset);
1126 /* Grab GPR config register range */
1127 imx6_pcie->iomuxc_gpr =
1128 syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr");
1129 if (IS_ERR(imx6_pcie->iomuxc_gpr)) {
1130 dev_err(dev, "unable to find iomuxc registers\n");
1131 return PTR_ERR(imx6_pcie->iomuxc_gpr);
1134 /* Grab PCIe PHY Tx Settings */
1135 if (of_property_read_u32(node, "fsl,tx-deemph-gen1",
1136 &imx6_pcie->tx_deemph_gen1))
1137 imx6_pcie->tx_deemph_gen1 = 0;
1139 if (of_property_read_u32(node, "fsl,tx-deemph-gen2-3p5db",
1140 &imx6_pcie->tx_deemph_gen2_3p5db))
1141 imx6_pcie->tx_deemph_gen2_3p5db = 0;
1143 if (of_property_read_u32(node, "fsl,tx-deemph-gen2-6db",
1144 &imx6_pcie->tx_deemph_gen2_6db))
1145 imx6_pcie->tx_deemph_gen2_6db = 20;
1147 if (of_property_read_u32(node, "fsl,tx-swing-full",
1148 &imx6_pcie->tx_swing_full))
1149 imx6_pcie->tx_swing_full = 127;
1151 if (of_property_read_u32(node, "fsl,tx-swing-low",
1152 &imx6_pcie->tx_swing_low))
1153 imx6_pcie->tx_swing_low = 127;
1155 /* Limit link speed */
1156 ret = of_property_read_u32(node, "fsl,max-link-speed",
1157 &imx6_pcie->link_gen);
1159 imx6_pcie->link_gen = 1;
1161 imx6_pcie->vpcie = devm_regulator_get_optional(&pdev->dev, "vpcie");
1162 if (IS_ERR(imx6_pcie->vpcie)) {
1163 if (PTR_ERR(imx6_pcie->vpcie) != -ENODEV)
1164 return PTR_ERR(imx6_pcie->vpcie);
1165 imx6_pcie->vpcie = NULL;
1168 platform_set_drvdata(pdev, imx6_pcie);
1170 ret = imx6_pcie_attach_pd(dev);
1174 ret = imx6_add_pcie_port(imx6_pcie, pdev);
1178 if (pci_msi_enabled()) {
1179 u8 offset = dw_pcie_find_capability(pci, PCI_CAP_ID_MSI);
1180 val = dw_pcie_readw_dbi(pci, offset + PCI_MSI_FLAGS);
1181 val |= PCI_MSI_FLAGS_ENABLE;
1182 dw_pcie_writew_dbi(pci, offset + PCI_MSI_FLAGS, val);
1188 static void imx6_pcie_shutdown(struct platform_device *pdev)
1190 struct imx6_pcie *imx6_pcie = platform_get_drvdata(pdev);
1192 /* bring down link, so bootloader gets clean state in case of reboot */
1193 imx6_pcie_assert_core_reset(imx6_pcie);
1196 static const struct imx6_pcie_drvdata drvdata[] = {
1199 .flags = IMX6_PCIE_FLAG_IMX6_PHY |
1200 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE,
1201 .dbi_length = 0x200,
1205 .flags = IMX6_PCIE_FLAG_IMX6_PHY |
1206 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE |
1207 IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
1211 .flags = IMX6_PCIE_FLAG_IMX6_PHY |
1212 IMX6_PCIE_FLAG_IMX6_SPEED_CHANGE,
1216 .flags = IMX6_PCIE_FLAG_SUPPORTS_SUSPEND,
1223 static const struct of_device_id imx6_pcie_of_match[] = {
1224 { .compatible = "fsl,imx6q-pcie", .data = &drvdata[IMX6Q], },
1225 { .compatible = "fsl,imx6sx-pcie", .data = &drvdata[IMX6SX], },
1226 { .compatible = "fsl,imx6qp-pcie", .data = &drvdata[IMX6QP], },
1227 { .compatible = "fsl,imx7d-pcie", .data = &drvdata[IMX7D], },
1228 { .compatible = "fsl,imx8mq-pcie", .data = &drvdata[IMX8MQ], } ,
1232 static struct platform_driver imx6_pcie_driver = {
1234 .name = "imx6q-pcie",
1235 .of_match_table = imx6_pcie_of_match,
1236 .suppress_bind_attrs = true,
1237 .pm = &imx6_pcie_pm_ops,
1238 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
1240 .probe = imx6_pcie_probe,
1241 .shutdown = imx6_pcie_shutdown,
1244 static void imx6_pcie_quirk(struct pci_dev *dev)
1246 struct pci_bus *bus = dev->bus;
1247 struct pcie_port *pp = bus->sysdata;
1249 /* Bus parent is the PCI bridge, its parent is this platform driver */
1250 if (!bus->dev.parent || !bus->dev.parent->parent)
1253 /* Make sure we only quirk devices associated with this driver */
1254 if (bus->dev.parent->parent->driver != &imx6_pcie_driver.driver)
1257 if (pci_is_root_bus(bus)) {
1258 struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
1259 struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci);
1262 * Limit config length to avoid the kernel reading beyond
1263 * the register set and causing an abort on i.MX 6Quad
1265 if (imx6_pcie->drvdata->dbi_length) {
1266 dev->cfg_size = imx6_pcie->drvdata->dbi_length;
1267 dev_info(&dev->dev, "Limiting cfg_size to %d\n",
1272 DECLARE_PCI_FIXUP_CLASS_HEADER(PCI_VENDOR_ID_SYNOPSYS, 0xabcd,
1273 PCI_CLASS_BRIDGE_PCI, 8, imx6_pcie_quirk);
1275 static int __init imx6_pcie_init(void)
1279 * Since probe() can be deferred we need to make sure that
1280 * hook_fault_code is not called after __init memory is freed
1281 * by kernel and since imx6q_pcie_abort_handler() is a no-op,
1282 * we can install the handler here without risking it
1283 * accessing some uninitialized driver state.
1285 hook_fault_code(8, imx6q_pcie_abort_handler, SIGBUS, 0,
1286 "external abort on non-linefetch");
1289 return platform_driver_register(&imx6_pcie_driver);
1291 device_initcall(imx6_pcie_init);