Re: [PATCH v8 08/16] PCI: imx6: Simplify switch-case logic by involve init_phy callback

From: Manivannan Sadhasivam
Date: Fri Jan 19 2024 - 03:26:23 EST

On Mon, Jan 08, 2024 at 06:21:37PM -0500, Frank Li wrote:
> Simplify switch-case logic by involve init_phy callback.
>

"Instead of using the switch case statement to initialize the PHY handled by
this driver itself, let's introduce a new callback init_phy() and define it for
platforms that require it. This simplifies the code."

> Signed-off-by: Frank Li <Frank.Li@xxxxxxx>

Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>

- Mani

> ---
>
> Notes:
> Change from v7 to v8:
> - rework commit message
> - wrap comments to 100 chars
> - return 0 at imx7d_pcie_init_phy()
>
> change from v1 to v4:
> - none
>
> drivers/pci/controller/dwc/pci-imx6.c | 134 +++++++++++++-------------
> 1 file changed, 69 insertions(+), 65 deletions(-)
>
> diff --git a/drivers/pci/controller/dwc/pci-imx6.c b/drivers/pci/controller/dwc/pci-imx6.c
> index fd83af238fa60..ac338a88fe21e 100644
> --- a/drivers/pci/controller/dwc/pci-imx6.c
> +++ b/drivers/pci/controller/dwc/pci-imx6.c
> @@ -69,6 +69,9 @@ enum imx6_pcie_variants {
> #define IMX6_PCIE_MAX_CLKS 6
>
> #define IMX6_PCIE_MAX_INSTANCES 2
> +
> +struct imx6_pcie;
> +
> struct imx6_pcie_drvdata {
> enum imx6_pcie_variants variant;
> enum dw_pcie_device_mode mode;
> @@ -81,6 +84,7 @@ struct imx6_pcie_drvdata {
> const u32 ltssm_mask;
> const u32 mode_off[IMX6_PCIE_MAX_INSTANCES];
> const u32 mode_mask[IMX6_PCIE_MAX_INSTANCES];
> + int (*init_phy)(struct imx6_pcie *pcie);
> };
>
> struct imx6_pcie {
> @@ -322,76 +326,66 @@ static int pcie_phy_write(struct imx6_pcie *imx6_pcie, int addr, u16 data)
> return 0;
> }
>
> -static void imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie)
> +static int imx8mq_pcie_init_phy(struct imx6_pcie *imx6_pcie)
> {
> - switch (imx6_pcie->drvdata->variant) {
> - case IMX8MM:
> - case IMX8MM_EP:
> - case IMX8MP:
> - case IMX8MP_EP:
> - /*
> - * The PHY initialization had been done in the PHY
> - * driver, break here directly.
> - */
> - break;
> - case IMX8MQ:
> - case IMX8MQ_EP:
> - /*
> - * TODO: Currently this code assumes external
> - * oscillator is being used
> - */
> + /* TODO: Currently this code assumes external oscillator is being used */
> + regmap_update_bits(imx6_pcie->iomuxc_gpr,
> + imx6_pcie_grp_offset(imx6_pcie),
> + IMX8MQ_GPR_PCIE_REF_USE_PAD,
> + IMX8MQ_GPR_PCIE_REF_USE_PAD);
> + /*
> + * Regarding the datasheet, the PCIE_VPH is suggested to be 1.8V. If the PCIE_VPH is
> + * supplied by 3.3V, the VREG_BYPASS should be cleared to zero.
> + */
> + if (imx6_pcie->vph && regulator_get_voltage(imx6_pcie->vph) > 3000000)
> regmap_update_bits(imx6_pcie->iomuxc_gpr,
> imx6_pcie_grp_offset(imx6_pcie),
> - IMX8MQ_GPR_PCIE_REF_USE_PAD,
> - IMX8MQ_GPR_PCIE_REF_USE_PAD);
> - /*
> - * Regarding the datasheet, the PCIE_VPH is suggested
> - * to be 1.8V. If the PCIE_VPH is supplied by 3.3V, the
> - * VREG_BYPASS should be cleared to zero.
> - */
> - if (imx6_pcie->vph &&
> - regulator_get_voltage(imx6_pcie->vph) > 3000000)
> - regmap_update_bits(imx6_pcie->iomuxc_gpr,
> - imx6_pcie_grp_offset(imx6_pcie),
> - IMX8MQ_GPR_PCIE_VREG_BYPASS,
> - 0);
> - break;
> - case IMX7D:
> - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
> - IMX7D_GPR12_PCIE_PHY_REFCLK_SEL, 0);
> - break;
> - case IMX6SX:
> - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
> - IMX6SX_GPR12_PCIE_RX_EQ_MASK,
> - IMX6SX_GPR12_PCIE_RX_EQ_2);
> - fallthrough;
> - default:
> - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
> + IMX8MQ_GPR_PCIE_VREG_BYPASS,
> + 0);
> +
> + return 0;
> +}
> +
> +static int imx7d_pcie_init_phy(struct imx6_pcie *imx6_pcie)
> +{
> + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12, IMX7D_GPR12_PCIE_PHY_REFCLK_SEL, 0);
> +
> + return 0;
> +}
> +
> +static int imx6_pcie_init_phy(struct imx6_pcie *imx6_pcie)
> +{
> + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
> IMX6Q_GPR12_PCIE_CTL_2, 0 << 10);
>
> - /* configure constant input signal to the pcie ctrl and phy */
> - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
> - IMX6Q_GPR12_LOS_LEVEL, 9 << 4);
> -
> - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
> - IMX6Q_GPR8_TX_DEEMPH_GEN1,
> - imx6_pcie->tx_deemph_gen1 << 0);
> - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
> - IMX6Q_GPR8_TX_DEEMPH_GEN2_3P5DB,
> - imx6_pcie->tx_deemph_gen2_3p5db << 6);
> - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
> - IMX6Q_GPR8_TX_DEEMPH_GEN2_6DB,
> - imx6_pcie->tx_deemph_gen2_6db << 12);
> - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
> - IMX6Q_GPR8_TX_SWING_FULL,
> - imx6_pcie->tx_swing_full << 18);
> - regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
> - IMX6Q_GPR8_TX_SWING_LOW,
> - imx6_pcie->tx_swing_low << 25);
> - break;
> - }
> + /* configure constant input signal to the pcie ctrl and phy */
> + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
> + IMX6Q_GPR12_LOS_LEVEL, 9 << 4);
> +
> + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
> + IMX6Q_GPR8_TX_DEEMPH_GEN1,
> + imx6_pcie->tx_deemph_gen1 << 0);
> + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
> + IMX6Q_GPR8_TX_DEEMPH_GEN2_3P5DB,
> + imx6_pcie->tx_deemph_gen2_3p5db << 6);
> + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
> + IMX6Q_GPR8_TX_DEEMPH_GEN2_6DB,
> + imx6_pcie->tx_deemph_gen2_6db << 12);
> + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
> + IMX6Q_GPR8_TX_SWING_FULL,
> + imx6_pcie->tx_swing_full << 18);
> + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR8,
> + IMX6Q_GPR8_TX_SWING_LOW,
> + imx6_pcie->tx_swing_low << 25);
> + return 0;
> +}
>
> - imx6_pcie_configure_type(imx6_pcie);
> +static int imx6sx_pcie_init_phy(struct imx6_pcie *imx6_pcie)
> +{
> + regmap_update_bits(imx6_pcie->iomuxc_gpr, IOMUXC_GPR12,
> + IMX6SX_GPR12_PCIE_RX_EQ_MASK, IMX6SX_GPR12_PCIE_RX_EQ_2);
> +
> + return imx6_pcie_init_phy(imx6_pcie);
> }
>
> static void imx7d_pcie_wait_for_phy_pll_lock(struct imx6_pcie *imx6_pcie)
> @@ -902,7 +896,11 @@ static int imx6_pcie_host_init(struct dw_pcie_rp *pp)
> }
>
> imx6_pcie_assert_core_reset(imx6_pcie);
> - imx6_pcie_init_phy(imx6_pcie);
> +
> + if (imx6_pcie->drvdata->init_phy)
> + imx6_pcie->drvdata->init_phy(imx6_pcie);
> +
> + imx6_pcie_configure_type(imx6_pcie);
>
> ret = imx6_pcie_clk_enable(imx6_pcie);
> if (ret) {
> @@ -1386,6 +1384,7 @@ static const struct imx6_pcie_drvdata drvdata[] = {
> .ltssm_mask = IMX6Q_GPR12_PCIE_CTL_2,
> .mode_off[0] = IOMUXC_GPR12,
> .mode_mask[0] = IMX6Q_GPR12_DEVICE_TYPE,
> + .init_phy = imx6_pcie_init_phy,
> },
> [IMX6SX] = {
> .variant = IMX6SX,
> @@ -1399,6 +1398,7 @@ static const struct imx6_pcie_drvdata drvdata[] = {
> .ltssm_mask = IMX6Q_GPR12_PCIE_CTL_2,
> .mode_off[0] = IOMUXC_GPR12,
> .mode_mask[0] = IMX6Q_GPR12_DEVICE_TYPE,
> + .init_phy = imx6sx_pcie_init_phy,
> },
> [IMX6QP] = {
> .variant = IMX6QP,
> @@ -1413,6 +1413,7 @@ static const struct imx6_pcie_drvdata drvdata[] = {
> .ltssm_mask = IMX6Q_GPR12_PCIE_CTL_2,
> .mode_off[0] = IOMUXC_GPR12,
> .mode_mask[0] = IMX6Q_GPR12_DEVICE_TYPE,
> + .init_phy = imx6_pcie_init_phy,
> },
> [IMX7D] = {
> .variant = IMX7D,
> @@ -1424,6 +1425,7 @@ static const struct imx6_pcie_drvdata drvdata[] = {
> .clks_cnt = ARRAY_SIZE(imx6_3clks_bus_pcie_phy),
> .mode_off[0] = IOMUXC_GPR12,
> .mode_mask[0] = IMX6Q_GPR12_DEVICE_TYPE,
> + .init_phy = imx7d_pcie_init_phy,
> },
> [IMX8MQ] = {
> .variant = IMX8MQ,
> @@ -1436,6 +1438,7 @@ static const struct imx6_pcie_drvdata drvdata[] = {
> .mode_mask[0] = IMX6Q_GPR12_DEVICE_TYPE,
> .mode_off[1] = IOMUXC_GPR12,
> .mode_mask[1] = IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE,
> + .init_phy = imx8mq_pcie_init_phy,
> },
> [IMX8MM] = {
> .variant = IMX8MM,
> @@ -1471,6 +1474,7 @@ static const struct imx6_pcie_drvdata drvdata[] = {
> .mode_mask[0] = IMX6Q_GPR12_DEVICE_TYPE,
> .mode_off[1] = IOMUXC_GPR12,
> .mode_mask[1] = IMX8MQ_GPR12_PCIE2_CTRL_DEVICE_TYPE,
> + .init_phy = imx8mq_pcie_init_phy,
> },
> [IMX8MM_EP] = {
> .variant = IMX8MM_EP,
> --
> 2.34.1
>

--
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