2 * PCIe host controller driver for Freescale i.MX6 SoCs
4 * Copyright (C) 2013 Kosagi
5 * http://www.kosagi.com
7 * Author: Sean Cross <xobs@kosagi.com>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
14 #include <linux/clk.h>
15 #include <linux/delay.h>
16 #include <linux/gpio.h>
17 #include <linux/kernel.h>
18 #include <linux/mfd/syscon.h>
19 #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
20 #include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
21 #include <linux/module.h>
22 #include <linux/of_gpio.h>
23 #include <linux/of_device.h>
24 #include <linux/pci.h>
25 #include <linux/platform_device.h>
26 #include <linux/regmap.h>
27 #include <linux/regulator/consumer.h>
28 #include <linux/resource.h>
29 #include <linux/signal.h>
30 #include <linux/types.h>
31 #include <linux/interrupt.h>
32 #include <linux/reset.h>
34 #include "pcie-designware.h"
36 #define to_imx6_pcie(x) dev_get_drvdata((x)->dev)
38 enum imx6_pcie_variants {
48 bool gpio_active_high;
51 struct clk *pcie_inbound_axi;
53 struct regmap *iomuxc_gpr;
54 struct reset_control *pciephy_reset;
55 struct reset_control *apps_reset;
56 enum imx6_pcie_variants variant;
58 u32 tx_deemph_gen2_3p5db;
59 u32 tx_deemph_gen2_6db;
63 struct regulator *vpcie;
66 /* Parameters for the waiting for PCIe PHY PLL to lock on i.MX7 */
67 #define PHY_PLL_LOCK_WAIT_MAX_RETRIES 2000
68 #define PHY_PLL_LOCK_WAIT_USLEEP_MIN 50
69 #define PHY_PLL_LOCK_WAIT_USLEEP_MAX 200
71 /* PCIe Root Complex registers (memory-mapped) */
72 #define PCIE_RC_LCR 0x7c
73 #define PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN1 0x1
74 #define PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN2 0x2
75 #define PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK 0xf
77 #define PCIE_RC_LCSR 0x80
79 /* PCIe Port Logic registers (memory-mapped) */
80 #define PL_OFFSET 0x700
81 #define PCIE_PL_PFLR (PL_OFFSET + 0x08)
82 #define PCIE_PL_PFLR_LINK_STATE_MASK (0x3f << 16)
83 #define PCIE_PL_PFLR_FORCE_LINK (1 << 15)
84 #define PCIE_PHY_DEBUG_R0 (PL_OFFSET + 0x28)
85 #define PCIE_PHY_DEBUG_R1 (PL_OFFSET + 0x2c)
87 #define PCIE_PHY_CTRL (PL_OFFSET + 0x114)
88 #define PCIE_PHY_CTRL_DATA_LOC 0
89 #define PCIE_PHY_CTRL_CAP_ADR_LOC 16
90 #define PCIE_PHY_CTRL_CAP_DAT_LOC 17
91 #define PCIE_PHY_CTRL_WR_LOC 18
92 #define PCIE_PHY_CTRL_RD_LOC 19
94 #define PCIE_PHY_STAT (PL_OFFSET + 0x110)
95 #define PCIE_PHY_STAT_ACK_LOC 16
97 #define PCIE_LINK_WIDTH_SPEED_CONTROL 0x80C
98 #define PORT_LOGIC_SPEED_CHANGE (0x1 << 17)
100 /* PHY registers (not memory-mapped) */
101 #define PCIE_PHY_RX_ASIC_OUT 0x100D
102 #define PCIE_PHY_RX_ASIC_OUT_VALID (1 << 0)
104 #define PHY_RX_OVRD_IN_LO 0x1005
105 #define PHY_RX_OVRD_IN_LO_RX_DATA_EN (1 << 5)
106 #define PHY_RX_OVRD_IN_LO_RX_PLL_EN (1 << 3)
108 static int pcie_phy_poll_ack(struct imx6_pcie *imx6_pcie, int exp_val)
110 struct dw_pcie *pci = imx6_pcie->pci;
112 u32 max_iterations = 10;
113 u32 wait_counter = 0;
116 val = dw_pcie_readl_dbi(pci, PCIE_PHY_STAT);
117 val = (val >> PCIE_PHY_STAT_ACK_LOC) & 0x1;
124 } while (wait_counter < max_iterations);
129 static int pcie_phy_wait_ack(struct imx6_pcie *imx6_pcie, int addr)
131 struct dw_pcie *pci = imx6_pcie->pci;
135 val = addr << PCIE_PHY_CTRL_DATA_LOC;
136 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
138 val |= (0x1 << PCIE_PHY_CTRL_CAP_ADR_LOC);
139 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
141 ret = pcie_phy_poll_ack(imx6_pcie, 1);
145 val = addr << PCIE_PHY_CTRL_DATA_LOC;
146 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, val);
148 return pcie_phy_poll_ack(imx6_pcie, 0);
151 /* Read from the 16-bit PCIe PHY control registers (not memory-mapped) */
152 static int pcie_phy_read(struct imx6_pcie *imx6_pcie, int addr, int *data)
154 struct dw_pcie *pci = imx6_pcie->pci;
158 ret = pcie_phy_wait_ack(imx6_pcie, addr);
162 /* assert Read signal */
163 phy_ctl = 0x1 << PCIE_PHY_CTRL_RD_LOC;
164 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, phy_ctl);
166 ret = pcie_phy_poll_ack(imx6_pcie, 1);
170 val = dw_pcie_readl_dbi(pci, PCIE_PHY_STAT);
171 *data = val & 0xffff;
173 /* deassert Read signal */
174 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, 0x00);
176 return pcie_phy_poll_ack(imx6_pcie, 0);
179 static int pcie_phy_write(struct imx6_pcie *imx6_pcie, int addr, int data)
181 struct dw_pcie *pci = imx6_pcie->pci;
187 ret = pcie_phy_wait_ack(imx6_pcie, addr);
191 var = data << PCIE_PHY_CTRL_DATA_LOC;
192 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
195 var |= (0x1 << PCIE_PHY_CTRL_CAP_DAT_LOC);
196 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
198 ret = pcie_phy_poll_ack(imx6_pcie, 1);
202 /* deassert cap data */
203 var = data << PCIE_PHY_CTRL_DATA_LOC;
204 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
206 /* wait for ack de-assertion */
207 ret = pcie_phy_poll_ack(imx6_pcie, 0);
211 /* assert wr signal */
212 var = 0x1 << PCIE_PHY_CTRL_WR_LOC;
213 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
216 ret = pcie_phy_poll_ack(imx6_pcie, 1);
220 /* deassert wr signal */
221 var = data << PCIE_PHY_CTRL_DATA_LOC;
222 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, var);
224 /* wait for ack de-assertion */
225 ret = pcie_phy_poll_ack(imx6_pcie, 0);
229 dw_pcie_writel_dbi(pci, PCIE_PHY_CTRL, 0x0);
234 static void imx6_pcie_reset_phy(struct imx6_pcie *imx6_pcie)
238 pcie_phy_read(imx6_pcie, PHY_RX_OVRD_IN_LO, &tmp);
239 tmp |= (PHY_RX_OVRD_IN_LO_RX_DATA_EN |
240 PHY_RX_OVRD_IN_LO_RX_PLL_EN);
241 pcie_phy_write(imx6_pcie, PHY_RX_OVRD_IN_LO, tmp);
243 usleep_range(2000, 3000);
245 pcie_phy_read(imx6_pcie, PHY_RX_OVRD_IN_LO, &tmp);
246 tmp &= ~(PHY_RX_OVRD_IN_LO_RX_DATA_EN |
247 PHY_RX_OVRD_IN_LO_RX_PLL_EN);
248 pcie_phy_write(imx6_pcie, PHY_RX_OVRD_IN_LO, tmp);
251 /* Added for PCI abort handling */
252 static int imx6q_pcie_abort_handler(unsigned long addr,
253 unsigned int fsr, struct pt_regs *regs)
255 unsigned long pc = instruction_pointer(regs);
256 unsigned long instr = *(unsigned long *)pc;
257 int reg = (instr >> 12) & 15;
260 * If the instruction being executed was a read,
261 * make it look like it read all-ones.
263 if ((instr & 0x0c100000) == 0x04100000) {
266 if (instr & 0x00400000)
271 regs->uregs[reg] = val;
276 if ((instr & 0x0e100090) == 0x00100090) {
277 regs->uregs[reg] = -1;
285 static void imx6_pcie_assert_core_reset(struct imx6_pcie *imx6_pcie)
287 struct device *dev = imx6_pcie->pci->dev;
289 switch (imx6_pcie->variant) {
291 reset_control_assert(imx6_pcie->pciephy_reset);
292 reset_control_assert(imx6_pcie->apps_reset);
295 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
296 IMX6SX_GPR12_PCIE_TEST_POWERDOWN,
297 IMX6SX_GPR12_PCIE_TEST_POWERDOWN);
298 /* Force PCIe PHY reset */
299 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5,
300 IMX6SX_GPR5_PCIE_BTNRST_RESET,
301 IMX6SX_GPR5_PCIE_BTNRST_RESET);
304 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
305 IMX6Q_GPR1_PCIE_SW_RST,
306 IMX6Q_GPR1_PCIE_SW_RST);
309 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
310 IMX6Q_GPR1_PCIE_TEST_PD, 1 << 18);
311 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
312 IMX6Q_GPR1_PCIE_REF_CLK_EN, 0 << 16);
316 if (imx6_pcie->vpcie && regulator_is_enabled(imx6_pcie->vpcie) > 0) {
317 int ret = regulator_disable(imx6_pcie->vpcie);
320 dev_err(dev, "failed to disable vpcie regulator: %d\n",
325 static int imx6_pcie_enable_ref_clk(struct imx6_pcie *imx6_pcie)
327 struct dw_pcie *pci = imx6_pcie->pci;
328 struct device *dev = pci->dev;
331 switch (imx6_pcie->variant) {
333 ret = clk_prepare_enable(imx6_pcie->pcie_inbound_axi);
335 dev_err(dev, "unable to enable pcie_axi clock\n");
339 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
340 IMX6SX_GPR12_PCIE_TEST_POWERDOWN, 0);
342 case IMX6QP: /* FALLTHROUGH */
344 /* power up core phy and enable ref clock */
345 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
346 IMX6Q_GPR1_PCIE_TEST_PD, 0 << 18);
348 * the async reset input need ref clock to sync internally,
349 * when the ref clock comes after reset, internal synced
350 * reset time is too short, cannot meet the requirement.
351 * add one ~10us delay here.
354 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
355 IMX6Q_GPR1_PCIE_REF_CLK_EN, 1 << 16);
364 static void imx7d_pcie_wait_for_phy_pll_lock(struct imx6_pcie *imx6_pcie)
367 unsigned int retries;
368 struct device *dev = imx6_pcie->pci->dev;
370 for (retries = 0; retries < PHY_PLL_LOCK_WAIT_MAX_RETRIES; retries++) {
371 regmap_read(imx6_pcie->iomuxc_gpr, IOMUXC_GPR22, &val);
373 if (val & IMX7D_GPR22_PCIE_PHY_PLL_LOCKED)
376 usleep_range(PHY_PLL_LOCK_WAIT_USLEEP_MIN,
377 PHY_PLL_LOCK_WAIT_USLEEP_MAX);
380 dev_err(dev, "PCIe PLL lock timeout\n");
383 static void imx6_pcie_deassert_core_reset(struct imx6_pcie *imx6_pcie)
385 struct dw_pcie *pci = imx6_pcie->pci;
386 struct device *dev = pci->dev;
389 if (imx6_pcie->vpcie && !regulator_is_enabled(imx6_pcie->vpcie)) {
390 ret = regulator_enable(imx6_pcie->vpcie);
392 dev_err(dev, "failed to enable vpcie regulator: %d\n",
398 ret = clk_prepare_enable(imx6_pcie->pcie_phy);
400 dev_err(dev, "unable to enable pcie_phy clock\n");
404 ret = clk_prepare_enable(imx6_pcie->pcie_bus);
406 dev_err(dev, "unable to enable pcie_bus clock\n");
410 ret = clk_prepare_enable(imx6_pcie->pcie);
412 dev_err(dev, "unable to enable pcie clock\n");
416 ret = imx6_pcie_enable_ref_clk(imx6_pcie);
418 dev_err(dev, "unable to enable pcie ref clock\n");
422 /* allow the clocks to stabilize */
423 usleep_range(200, 500);
425 /* Some boards don't have PCIe reset GPIO. */
426 if (gpio_is_valid(imx6_pcie->reset_gpio)) {
427 gpio_set_value_cansleep(imx6_pcie->reset_gpio,
428 imx6_pcie->gpio_active_high);
430 gpio_set_value_cansleep(imx6_pcie->reset_gpio,
431 !imx6_pcie->gpio_active_high);
434 switch (imx6_pcie->variant) {
436 reset_control_deassert(imx6_pcie->pciephy_reset);
437 imx7d_pcie_wait_for_phy_pll_lock(imx6_pcie);
440 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR5,
441 IMX6SX_GPR5_PCIE_BTNRST_RESET, 0);
444 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR1,
445 IMX6Q_GPR1_PCIE_SW_RST, 0);
447 usleep_range(200, 500);
449 case IMX6Q: /* Nothing to do */
456 clk_disable_unprepare(imx6_pcie->pcie);
458 clk_disable_unprepare(imx6_pcie->pcie_bus);
460 clk_disable_unprepare(imx6_pcie->pcie_phy);
462 if (imx6_pcie->vpcie && regulator_is_enabled(imx6_pcie->vpcie) > 0) {
463 ret = regulator_disable(imx6_pcie->vpcie);
465 dev_err(dev, "failed to disable vpcie regulator: %d\n",
470 static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie)
472 switch (imx6_pcie->variant) {
474 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
475 IMX7D_GPR12_PCIE_PHY_REFCLK_SEL, 0);
478 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
479 IMX6SX_GPR12_PCIE_RX_EQ_MASK,
480 IMX6SX_GPR12_PCIE_RX_EQ_2);
483 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
484 IMX6Q_GPR12_PCIE_CTL_2, 0 << 10);
486 /* configure constant input signal to the pcie ctrl and phy */
487 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
488 IMX6Q_GPR12_LOS_LEVEL, 9 << 4);
490 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
491 IMX6Q_GPR8_TX_DEEMPH_GEN1,
492 imx6_pcie->tx_deemph_gen1 << 0);
493 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
494 IMX6Q_GPR8_TX_DEEMPH_GEN2_3P5DB,
495 imx6_pcie->tx_deemph_gen2_3p5db << 6);
496 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
497 IMX6Q_GPR8_TX_DEEMPH_GEN2_6DB,
498 imx6_pcie->tx_deemph_gen2_6db << 12);
499 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
500 IMX6Q_GPR8_TX_SWING_FULL,
501 imx6_pcie->tx_swing_full << 18);
502 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
503 IMX6Q_GPR8_TX_SWING_LOW,
504 imx6_pcie->tx_swing_low << 25);
508 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
509 IMX6Q_GPR12_DEVICE_TYPE, PCI_EXP_TYPE_ROOT_PORT << 12);
512 static int imx6_pcie_wait_for_link(struct imx6_pcie *imx6_pcie)
514 struct dw_pcie *pci = imx6_pcie->pci;
515 struct device *dev = pci->dev;
517 /* check if the link is up or not */
518 if (!dw_pcie_wait_for_link(pci))
521 dev_dbg(dev, "DEBUG_R0: 0x%08x, DEBUG_R1: 0x%08x\n",
522 dw_pcie_readl_dbi(pci, PCIE_PHY_DEBUG_R0),
523 dw_pcie_readl_dbi(pci, PCIE_PHY_DEBUG_R1));
527 static int imx6_pcie_wait_for_speed_change(struct imx6_pcie *imx6_pcie)
529 struct dw_pcie *pci = imx6_pcie->pci;
530 struct device *dev = pci->dev;
532 unsigned int retries;
534 for (retries = 0; retries < 200; retries++) {
535 tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
536 /* Test if the speed change finished. */
537 if (!(tmp & PORT_LOGIC_SPEED_CHANGE))
539 usleep_range(100, 1000);
542 dev_err(dev, "Speed change timeout\n");
546 static irqreturn_t imx6_pcie_msi_handler(int irq, void *arg)
548 struct imx6_pcie *imx6_pcie = arg;
549 struct dw_pcie *pci = imx6_pcie->pci;
550 struct pcie_port *pp = &pci->pp;
552 return dw_handle_msi_irq(pp);
555 static int imx6_pcie_establish_link(struct imx6_pcie *imx6_pcie)
557 struct dw_pcie *pci = imx6_pcie->pci;
558 struct device *dev = pci->dev;
563 * Force Gen1 operation when starting the link. In case the link is
564 * started in Gen2 mode, there is a possibility the devices on the
565 * bus will not be detected at all. This happens with PCIe switches.
567 tmp = dw_pcie_readl_dbi(pci, PCIE_RC_LCR);
568 tmp &= ~PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK;
569 tmp |= PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN1;
570 dw_pcie_writel_dbi(pci, PCIE_RC_LCR, tmp);
573 if (imx6_pcie->variant == IMX7D)
574 reset_control_deassert(imx6_pcie->apps_reset);
576 regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
577 IMX6Q_GPR12_PCIE_CTL_2, 1 << 10);
579 ret = imx6_pcie_wait_for_link(imx6_pcie);
583 if (imx6_pcie->link_gen == 2) {
584 /* Allow Gen2 mode after the link is up. */
585 tmp = dw_pcie_readl_dbi(pci, PCIE_RC_LCR);
586 tmp &= ~PCIE_RC_LCR_MAX_LINK_SPEEDS_MASK;
587 tmp |= PCIE_RC_LCR_MAX_LINK_SPEEDS_GEN2;
588 dw_pcie_writel_dbi(pci, PCIE_RC_LCR, tmp);
591 * Start Directed Speed Change so the best possible
592 * speed both link partners support can be negotiated.
594 tmp = dw_pcie_readl_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL);
595 tmp |= PORT_LOGIC_SPEED_CHANGE;
596 dw_pcie_writel_dbi(pci, PCIE_LINK_WIDTH_SPEED_CONTROL, tmp);
598 if (imx6_pcie->variant != IMX7D) {
600 * On i.MX7, DIRECT_SPEED_CHANGE behaves differently
601 * from i.MX6 family when no link speed transition
602 * occurs and we go Gen1 -> yep, Gen1. The difference
603 * is that, in such case, it will not be cleared by HW
604 * which will cause the following code to report false
608 ret = imx6_pcie_wait_for_speed_change(imx6_pcie);
610 dev_err(dev, "Failed to bring link up!\n");
615 /* Make sure link training is finished as well! */
616 ret = imx6_pcie_wait_for_link(imx6_pcie);
618 dev_err(dev, "Failed to bring link up!\n");
622 dev_info(dev, "Link: Gen2 disabled\n");
625 tmp = dw_pcie_readl_dbi(pci, PCIE_RC_LCSR);
626 dev_info(dev, "Link up, Gen%i\n", (tmp >> 16) & 0xf);
630 dev_dbg(dev, "PHY DEBUG_R0=0x%08x DEBUG_R1=0x%08x\n",
631 dw_pcie_readl_dbi(pci, PCIE_PHY_DEBUG_R0),
632 dw_pcie_readl_dbi(pci, PCIE_PHY_DEBUG_R1));
633 imx6_pcie_reset_phy(imx6_pcie);
637 static int imx6_pcie_host_init(struct pcie_port *pp)
639 struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
640 struct imx6_pcie *imx6_pcie = to_imx6_pcie(pci);
642 imx6_pcie_assert_core_reset(imx6_pcie);
643 imx6_pcie_init_phy(imx6_pcie);
644 imx6_pcie_deassert_core_reset(imx6_pcie);
645 dw_pcie_setup_rc(pp);
646 imx6_pcie_establish_link(imx6_pcie);
648 if (IS_ENABLED(CONFIG_PCI_MSI))
649 dw_pcie_msi_init(pp);
654 static const struct dw_pcie_host_ops imx6_pcie_host_ops = {
655 .host_init = imx6_pcie_host_init,
658 static int imx6_add_pcie_port(struct imx6_pcie *imx6_pcie,
659 struct platform_device *pdev)
661 struct dw_pcie *pci = imx6_pcie->pci;
662 struct pcie_port *pp = &pci->pp;
663 struct device *dev = &pdev->dev;
666 if (IS_ENABLED(CONFIG_PCI_MSI)) {
667 pp->msi_irq = platform_get_irq_byname(pdev, "msi");
668 if (pp->msi_irq <= 0) {
669 dev_err(dev, "failed to get MSI irq\n");
673 ret = devm_request_irq(dev, pp->msi_irq,
674 imx6_pcie_msi_handler,
675 IRQF_SHARED | IRQF_NO_THREAD,
676 "mx6-pcie-msi", imx6_pcie);
678 dev_err(dev, "failed to request MSI irq\n");
683 pp->root_bus_nr = -1;
684 pp->ops = &imx6_pcie_host_ops;
686 ret = dw_pcie_host_init(pp);
688 dev_err(dev, "failed to initialize host\n");
695 static const struct dw_pcie_ops dw_pcie_ops = {
696 /* No special ops needed, but pcie-designware still expects this struct */
699 static int imx6_pcie_probe(struct platform_device *pdev)
701 struct device *dev = &pdev->dev;
703 struct imx6_pcie *imx6_pcie;
704 struct resource *dbi_base;
705 struct device_node *node = dev->of_node;
708 imx6_pcie = devm_kzalloc(dev, sizeof(*imx6_pcie), GFP_KERNEL);
712 pci = devm_kzalloc(dev, sizeof(*pci), GFP_KERNEL);
717 pci->ops = &dw_pcie_ops;
719 imx6_pcie->pci = pci;
721 (enum imx6_pcie_variants)of_device_get_match_data(dev);
723 dbi_base = platform_get_resource(pdev, IORESOURCE_MEM, 0);
724 pci->dbi_base = devm_ioremap_resource(dev, dbi_base);
725 if (IS_ERR(pci->dbi_base))
726 return PTR_ERR(pci->dbi_base);
729 imx6_pcie->reset_gpio = of_get_named_gpio(node, "reset-gpio", 0);
730 imx6_pcie->gpio_active_high = of_property_read_bool(node,
731 "reset-gpio-active-high");
732 if (gpio_is_valid(imx6_pcie->reset_gpio)) {
733 ret = devm_gpio_request_one(dev, imx6_pcie->reset_gpio,
734 imx6_pcie->gpio_active_high ?
735 GPIOF_OUT_INIT_HIGH :
739 dev_err(dev, "unable to get reset gpio\n");
742 } else if (imx6_pcie->reset_gpio == -EPROBE_DEFER) {
743 return imx6_pcie->reset_gpio;
747 imx6_pcie->pcie_phy = devm_clk_get(dev, "pcie_phy");
748 if (IS_ERR(imx6_pcie->pcie_phy)) {
749 dev_err(dev, "pcie_phy clock source missing or invalid\n");
750 return PTR_ERR(imx6_pcie->pcie_phy);
753 imx6_pcie->pcie_bus = devm_clk_get(dev, "pcie_bus");
754 if (IS_ERR(imx6_pcie->pcie_bus)) {
755 dev_err(dev, "pcie_bus clock source missing or invalid\n");
756 return PTR_ERR(imx6_pcie->pcie_bus);
759 imx6_pcie->pcie = devm_clk_get(dev, "pcie");
760 if (IS_ERR(imx6_pcie->pcie)) {
761 dev_err(dev, "pcie clock source missing or invalid\n");
762 return PTR_ERR(imx6_pcie->pcie);
765 switch (imx6_pcie->variant) {
767 imx6_pcie->pcie_inbound_axi = devm_clk_get(dev,
769 if (IS_ERR(imx6_pcie->pcie_inbound_axi)) {
770 dev_err(dev, "pcie_inbound_axi clock missing or invalid\n");
771 return PTR_ERR(imx6_pcie->pcie_inbound_axi);
775 imx6_pcie->pciephy_reset = devm_reset_control_get_exclusive(dev,
777 if (IS_ERR(imx6_pcie->pciephy_reset)) {
778 dev_err(dev, "Failed to get PCIEPHY reset control\n");
779 return PTR_ERR(imx6_pcie->pciephy_reset);
782 imx6_pcie->apps_reset = devm_reset_control_get_exclusive(dev,
784 if (IS_ERR(imx6_pcie->apps_reset)) {
785 dev_err(dev, "Failed to get PCIE APPS reset control\n");
786 return PTR_ERR(imx6_pcie->apps_reset);
793 /* Grab GPR config register range */
794 imx6_pcie->iomuxc_gpr =
795 syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr");
796 if (IS_ERR(imx6_pcie->iomuxc_gpr)) {
797 dev_err(dev, "unable to find iomuxc registers\n");
798 return PTR_ERR(imx6_pcie->iomuxc_gpr);
801 /* Grab PCIe PHY Tx Settings */
802 if (of_property_read_u32(node, "fsl,tx-deemph-gen1",
803 &imx6_pcie->tx_deemph_gen1))
804 imx6_pcie->tx_deemph_gen1 = 0;
806 if (of_property_read_u32(node, "fsl,tx-deemph-gen2-3p5db",
807 &imx6_pcie->tx_deemph_gen2_3p5db))
808 imx6_pcie->tx_deemph_gen2_3p5db = 0;
810 if (of_property_read_u32(node, "fsl,tx-deemph-gen2-6db",
811 &imx6_pcie->tx_deemph_gen2_6db))
812 imx6_pcie->tx_deemph_gen2_6db = 20;
814 if (of_property_read_u32(node, "fsl,tx-swing-full",
815 &imx6_pcie->tx_swing_full))
816 imx6_pcie->tx_swing_full = 127;
818 if (of_property_read_u32(node, "fsl,tx-swing-low",
819 &imx6_pcie->tx_swing_low))
820 imx6_pcie->tx_swing_low = 127;
822 /* Limit link speed */
823 ret = of_property_read_u32(node, "fsl,max-link-speed",
824 &imx6_pcie->link_gen);
826 imx6_pcie->link_gen = 1;
828 imx6_pcie->vpcie = devm_regulator_get_optional(&pdev->dev, "vpcie");
829 if (IS_ERR(imx6_pcie->vpcie)) {
830 if (PTR_ERR(imx6_pcie->vpcie) != -ENODEV)
831 return PTR_ERR(imx6_pcie->vpcie);
832 imx6_pcie->vpcie = NULL;
835 platform_set_drvdata(pdev, imx6_pcie);
837 ret = imx6_add_pcie_port(imx6_pcie, pdev);
844 static void imx6_pcie_shutdown(struct platform_device *pdev)
846 struct imx6_pcie *imx6_pcie = platform_get_drvdata(pdev);
848 /* bring down link, so bootloader gets clean state in case of reboot */
849 imx6_pcie_assert_core_reset(imx6_pcie);
852 static const struct of_device_id imx6_pcie_of_match[] = {
853 { .compatible = "fsl,imx6q-pcie", .data = (void *)IMX6Q, },
854 { .compatible = "fsl,imx6sx-pcie", .data = (void *)IMX6SX, },
855 { .compatible = "fsl,imx6qp-pcie", .data = (void *)IMX6QP, },
856 { .compatible = "fsl,imx7d-pcie", .data = (void *)IMX7D, },
860 static struct platform_driver imx6_pcie_driver = {
862 .name = "imx6q-pcie",
863 .of_match_table = imx6_pcie_of_match,
864 .suppress_bind_attrs = true,
866 .probe = imx6_pcie_probe,
867 .shutdown = imx6_pcie_shutdown,
870 static int __init imx6_pcie_init(void)
873 * Since probe() can be deferred we need to make sure that
874 * hook_fault_code is not called after __init memory is freed
875 * by kernel and since imx6q_pcie_abort_handler() is a no-op,
876 * we can install the handler here without risking it
877 * accessing some uninitialized driver state.
879 hook_fault_code(8, imx6q_pcie_abort_handler, SIGBUS, 0,
880 "external abort on non-linefetch");
882 return platform_driver_register(&imx6_pcie_driver);
884 device_initcall(imx6_pcie_init);