[PATCH v3 3/6] phy: freescale: imx8m-pcie: Add iMX8MP PCIe PHY support

From: Richard Zhu
Date: Thu Aug 18 2022 - 03:19:57 EST


Add the i.MX8MP PCIe PHY support

Signed-off-by: Richard Zhu <hongxing.zhu@xxxxxxx>
---
drivers/phy/freescale/phy-fsl-imx8m-pcie.c | 150 ++++++++++++++-------
1 file changed, 104 insertions(+), 46 deletions(-)

diff --git a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
index ad7d2edfc414..3463b4299f2f 100644
--- a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
+++ b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
@@ -11,6 +11,8 @@
#include <linux/mfd/syscon.h>
#include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
@@ -31,12 +33,10 @@
#define IMX8MM_PCIE_PHY_CMN_REG065 0x194
#define ANA_AUX_RX_TERM (BIT(7) | BIT(4))
#define ANA_AUX_TX_LVL GENMASK(3, 0)
-#define IMX8MM_PCIE_PHY_CMN_REG75 0x1D4
-#define PCIE_PHY_CMN_REG75_PLL_DONE 0x3
+#define IMX8MM_PCIE_PHY_CMN_REG075 0x1D4
+#define ANA_PLL_DONE 0x3
#define PCIE_PHY_TRSV_REG5 0x414
-#define PCIE_PHY_TRSV_REG5_GEN1_DEEMP 0x2D
#define PCIE_PHY_TRSV_REG6 0x418
-#define PCIE_PHY_TRSV_REG6_GEN2_DEEMP 0xF

#define IMX8MM_GPR_PCIE_REF_CLK_SEL GENMASK(25, 24)
#define IMX8MM_GPR_PCIE_REF_CLK_PLL FIELD_PREP(IMX8MM_GPR_PCIE_REF_CLK_SEL, 0x3)
@@ -47,16 +47,29 @@
#define IMX8MM_GPR_PCIE_SSC_EN BIT(16)
#define IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE BIT(9)

+#define IMX8MP_GPR_REG0 0x0
+#define IMX8MP_GPR_PHY_APB_RST BIT(4)
+#define IMX8MP_GPR_PHY_INIT_RST BIT(5)
+
+enum imx8_pcie_phy_type {
+ IMX8MM,
+ IMX8MP,
+};
+
struct imx8_pcie_phy {
void __iomem *base;
+ struct device *dev;
struct clk *clk;
struct phy *phy;
+ struct regmap *hsio_blk_ctrl;
struct regmap *iomuxc_gpr;
struct reset_control *reset;
+ struct reset_control *perst;
u32 refclk_pad_mode;
u32 tx_deemph_gen1;
u32 tx_deemph_gen2;
bool clkreq_unused;
+ enum imx8_pcie_phy_type variant;
};

static int imx8_pcie_phy_init(struct phy *phy)
@@ -68,31 +81,27 @@ static int imx8_pcie_phy_init(struct phy *phy)
reset_control_assert(imx8_phy->reset);

pad_mode = imx8_phy->refclk_pad_mode;
- /* Set AUX_EN_OVERRIDE 1'b0, when the CLKREQ# isn't hooked */
- regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
- IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE,
- imx8_phy->clkreq_unused ?
- 0 : IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE);
- regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
- IMX8MM_GPR_PCIE_AUX_EN,
- IMX8MM_GPR_PCIE_AUX_EN);
- regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
- IMX8MM_GPR_PCIE_POWER_OFF, 0);
- regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
- IMX8MM_GPR_PCIE_SSC_EN, 0);
-
- regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
- IMX8MM_GPR_PCIE_REF_CLK_SEL,
- pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT ?
- IMX8MM_GPR_PCIE_REF_CLK_EXT :
- IMX8MM_GPR_PCIE_REF_CLK_PLL);
- usleep_range(100, 200);
-
- /* Do the PHY common block reset */
- regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
- IMX8MM_GPR_PCIE_CMN_RST,
- IMX8MM_GPR_PCIE_CMN_RST);
- usleep_range(200, 500);
+ switch (imx8_phy->variant) {
+ case IMX8MM:
+ /* Tune PHY de-emphasis setting to pass PCIe compliance. */
+ if (imx8_phy->tx_deemph_gen1)
+ writel(imx8_phy->tx_deemph_gen1,
+ imx8_phy->base + PCIE_PHY_TRSV_REG5);
+ if (imx8_phy->tx_deemph_gen2)
+ writel(imx8_phy->tx_deemph_gen2,
+ imx8_phy->base + PCIE_PHY_TRSV_REG6);
+ break;
+ case IMX8MP:
+ reset_control_assert(imx8_phy->perst);
+
+ /* release pcie_phy_apb_reset and pcie_phy_init_resetn */
+ regmap_update_bits(imx8_phy->hsio_blk_ctrl, IMX8MP_GPR_REG0,
+ IMX8MP_GPR_PHY_APB_RST |
+ IMX8MP_GPR_PHY_INIT_RST,
+ IMX8MP_GPR_PHY_APB_RST |
+ IMX8MP_GPR_PHY_INIT_RST);
+ break;
+ }

if (pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT ||
pad_mode == IMX8_PCIE_REFCLK_PAD_UNUSED) {
@@ -120,20 +129,44 @@ static int imx8_pcie_phy_init(struct phy *phy)
imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG065);
}

- /* Tune PHY de-emphasis setting to pass PCIe compliance. */
- if (imx8_phy->tx_deemph_gen1)
- writel(imx8_phy->tx_deemph_gen1,
- imx8_phy->base + PCIE_PHY_TRSV_REG5);
- if (imx8_phy->tx_deemph_gen2)
- writel(imx8_phy->tx_deemph_gen2,
- imx8_phy->base + PCIE_PHY_TRSV_REG6);
+ /* Set AUX_EN_OVERRIDE 1'b0, when the CLKREQ# isn't hooked */
+ regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
+ IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE,
+ imx8_phy->clkreq_unused ?
+ 0 : IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE);
+ regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
+ IMX8MM_GPR_PCIE_AUX_EN,
+ IMX8MM_GPR_PCIE_AUX_EN);
+ regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
+ IMX8MM_GPR_PCIE_POWER_OFF, 0);
+ regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
+ IMX8MM_GPR_PCIE_SSC_EN, 0);
+
+ regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
+ IMX8MM_GPR_PCIE_REF_CLK_SEL,
+ pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT ?
+ IMX8MM_GPR_PCIE_REF_CLK_EXT :
+ IMX8MM_GPR_PCIE_REF_CLK_PLL);
+ usleep_range(100, 200);

- reset_control_deassert(imx8_phy->reset);
+ /* Do the PHY common block reset */
+ regmap_update_bits(imx8_phy->iomuxc_gpr, IOMUXC_GPR14,
+ IMX8MM_GPR_PCIE_CMN_RST,
+ IMX8MM_GPR_PCIE_CMN_RST);
+
+ switch (imx8_phy->variant) {
+ case IMX8MP:
+ reset_control_deassert(imx8_phy->perst);
+ fallthrough;
+ case IMX8MM:
+ reset_control_deassert(imx8_phy->reset);
+ usleep_range(200, 500);
+ break;
+ }

/* Polling to check the phy is ready or not. */
- ret = readl_poll_timeout(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG75,
- val, val == PCIE_PHY_CMN_REG75_PLL_DONE,
- 10, 20000);
+ ret = readl_poll_timeout(imx8_phy->base + IMX8MM_PCIE_PHY_CMN_REG075,
+ val, val == ANA_PLL_DONE, 10, 20000);
return ret;
}

@@ -160,18 +193,33 @@ static const struct phy_ops imx8_pcie_phy_ops = {
.owner = THIS_MODULE,
};

+static const struct of_device_id imx8_pcie_phy_of_match[] = {
+ {.compatible = "fsl,imx8mm-pcie-phy", .data = (void *)IMX8MM},
+ {.compatible = "fsl,imx8mp-pcie-phy", .data = (void *)IMX8MP},
+ { },
+};
+MODULE_DEVICE_TABLE(of, imx8_pcie_phy_of_match);
+
static int imx8_pcie_phy_probe(struct platform_device *pdev)
{
struct phy_provider *phy_provider;
struct device *dev = &pdev->dev;
+ const struct of_device_id *of_id;
struct device_node *np = dev->of_node;
struct imx8_pcie_phy *imx8_phy;
struct resource *res;

+ of_id = of_match_device(imx8_pcie_phy_of_match, dev);
+ if (!of_id)
+ return -EINVAL;
+
imx8_phy = devm_kzalloc(dev, sizeof(*imx8_phy), GFP_KERNEL);
if (!imx8_phy)
return -ENOMEM;

+ imx8_phy->dev = dev;
+ imx8_phy->variant = (enum imx8_pcie_phy_type)of_id->data;
+
/* get PHY refclk pad mode */
of_property_read_u32(np, "fsl,refclk-pad-mode",
&imx8_phy->refclk_pad_mode);
@@ -208,6 +256,22 @@ static int imx8_pcie_phy_probe(struct platform_device *pdev)
dev_err(dev, "Failed to get PCIEPHY reset control\n");
return PTR_ERR(imx8_phy->reset);
}
+ if (imx8_phy->variant == IMX8MP) {
+ /* Grab HSIO MIX config register range */
+ imx8_phy->hsio_blk_ctrl =
+ syscon_regmap_lookup_by_compatible("fsl,imx8mp-hsio-blk-ctrl");
+ if (IS_ERR(imx8_phy->hsio_blk_ctrl)) {
+ dev_err(dev, "Unable to find HSIO MIX registers\n");
+ return PTR_ERR(imx8_phy->hsio_blk_ctrl);
+ }
+
+ imx8_phy->perst =
+ devm_reset_control_get_exclusive(dev, "perst");
+ if (IS_ERR(imx8_phy->perst)) {
+ dev_err(dev, "Failed to get PCIE PHY PERST control\n");
+ return PTR_ERR(imx8_phy->perst);
+ }
+ }

res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
imx8_phy->base = devm_ioremap_resource(dev, res);
@@ -225,12 +289,6 @@ static int imx8_pcie_phy_probe(struct platform_device *pdev)
return PTR_ERR_OR_ZERO(phy_provider);
}

-static const struct of_device_id imx8_pcie_phy_of_match[] = {
- {.compatible = "fsl,imx8mm-pcie-phy",},
- { },
-};
-MODULE_DEVICE_TABLE(of, imx8_pcie_phy_of_match);
-
static struct platform_driver imx8_pcie_phy_driver = {
.probe = imx8_pcie_phy_probe,
.driver = {
--
2.25.1