[RESEND v12 3/4] phy: freescale: imx8m-pcie: Refine i.MX8MM PCIe PHY driver

Richard Zhu
2022-10-13T02:07:09Z

To make it more flexible and easy to expand. Refine i.MX8MM PCIe PHY
driver.
- Use gpr compatible string to avoid the codes duplications when add
another platform PCIe PHY support.
- Re-arrange the codes to let it more flexible and easy to expand.
No functional change. Re-arrange the TX tuning, since internal registers
can be wrote through APB interface before assertion of CMN_RST.

Signed-off-by: Richard Zhu <hongxing.zhu@nxp.com>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Tested-by: Marek Vasut <marex@denx.de>
Tested-by: Richard Leitner <richard.leitner@skidata.com>
Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
drivers/phy/freescale/phy-fsl-imx8m-pcie.c | 106 +++++++++++++--------
1 file changed, 66 insertions(+), 40 deletions(-)

diff --git a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
index 3c8c255499cd..3e494612db3c 100644
--- a/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
+++ b/drivers/phy/freescale/phy-fsl-imx8m-pcie.c
@@ -11,6 +11,7 @@
#include <linux/mfd/syscon.h>
#include <linux/mfd/syscon/imx7-iomuxc-gpr.h>
#include <linux/module.h>
+#include <linux/of_device.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
@@ -45,6 +46,15 @@
#define IMX8MM_GPR_PCIE_SSC_EN BIT(16)
#define IMX8MM_GPR_PCIE_AUX_EN_OVERRIDE BIT(9)

+enum imx8_pcie_phy_type {
+ IMX8MM,
+};
+
+struct imx8_pcie_phy_drvdata {
+ const char *gpr;
+ enum imx8_pcie_phy_type variant;
+};
+
struct imx8_pcie_phy {
void __iomem *base;
struct clk *clk;
@@ -55,6 +65,7 @@ struct imx8_pcie_phy {
u32 tx_deemph_gen1;
u32 tx_deemph_gen2;
bool clkreq_unused;
+ const struct imx8_pcie_phy_drvdata *drvdata;
};

static int imx8_pcie_phy_power_on(struct phy *phy)
@@ -66,31 +77,17 @@ static int imx8_pcie_phy_power_on(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->drvdata->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;
+ }

if (pad_mode == IMX8_PCIE_REFCLK_PAD_INPUT ||
pad_mode == IMX8_PCIE_REFCLK_PAD_UNUSED) {
@@ -118,15 +115,37 @@ static int imx8_pcie_phy_power_on(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);

- reset_control_deassert(imx8_phy->reset);
+ 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);
+
+ switch (imx8_phy->drvdata->variant) {
+ 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_REG075,
@@ -157,6 +176,17 @@ static const struct phy_ops imx8_pcie_phy_ops = {
.owner = THIS_MODULE,
};

+static const struct imx8_pcie_phy_drvdata imx8mm_drvdata = {
+ .gpr = "fsl,imx8mm-iomuxc-gpr",
+ .variant = IMX8MM,
+};
+
+static const struct of_device_id imx8_pcie_phy_of_match[] = {
+ {.compatible = "fsl,imx8mm-pcie-phy", .data = &imx8mm_drvdata, },
+ { },
+};
+MODULE_DEVICE_TABLE(of, imx8_pcie_phy_of_match);
+
static int imx8_pcie_phy_probe(struct platform_device *pdev)
{
struct phy_provider *phy_provider;
@@ -169,6 +199,8 @@ static int imx8_pcie_phy_probe(struct platform_device *pdev)
if (!imx8_phy)
return -ENOMEM;

+ imx8_phy->drvdata = of_device_get_match_data(dev);
+
/* get PHY refclk pad mode */
of_property_read_u32(np, "fsl,refclk-pad-mode",
&imx8_phy->refclk_pad_mode);
@@ -194,7 +226,7 @@ static int imx8_pcie_phy_probe(struct platform_device *pdev)

/* Grab GPR config register range */
imx8_phy->iomuxc_gpr =
- syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr");
+ syscon_regmap_lookup_by_compatible(imx8_phy->drvdata->gpr);
if (IS_ERR(imx8_phy->iomuxc_gpr)) {
dev_err(dev, "unable to find iomuxc registers\n");
return PTR_ERR(imx8_phy->iomuxc_gpr);
@@ -222,12 +254,6 @@ 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