mbox series

[v2,0/2] Add new UniPhier AHCI PHY driver

Message ID 1593507574-10007-1-git-send-email-hayashi.kunihiko@socionext.com
Headers show
Series Add new UniPhier AHCI PHY driver | expand

Message

Kunihiko Hayashi June 30, 2020, 8:59 a.m. UTC 
This series adds support for AHCI PHY interface implemented in Socionext
UniPhier SoCs. This driver supports PXs2 and PXs3 SoCs.

Changes since v1:
- dt-bindings: Fix items in reset-names

Kunihiko Hayashi (2):
  dt-bindings: phy: Add UniPhier AHCI PHY description
  phy: socionext: Add UniPhier AHCI PHY driver support

 .../bindings/phy/socionext,uniphier-ahci-phy.yaml  |  76 +++++
 drivers/phy/socionext/Kconfig                      |  10 +
 drivers/phy/socionext/Makefile                     |   1 +
 drivers/phy/socionext/phy-uniphier-ahci.c          | 335 +++++++++++++++++++++
 4 files changed, 422 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/phy/socionext,uniphier-ahci-phy.yaml
 create mode 100644 drivers/phy/socionext/phy-uniphier-ahci.c

Comments

Vinod Koul July 13, 2020, 5:05 a.m. UTC | #1 
On 30-06-20, 17:59, Kunihiko Hayashi wrote:

> +++ b/drivers/phy/socionext/phy-uniphier-ahci.c
> @@ -0,0 +1,335 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * phy-uniphier-ahci.c - PHY driver for UniPhier AHCI controller
> + * Copyright 2016-2018, Socionext Inc.

we are in 2020 now!

> +static int uniphier_ahciphy_pxs2_power_on(struct uniphier_ahciphy_priv *priv)
> +{
> +	int ret;
> +	u32 val;
> +
> +	/* enable reference clock for PHY */
> +	val = readl(priv->base + CKCTRL);
> +	val |= CKCTRL_REF_SSP_EN;
> +	writel(val, priv->base + CKCTRL);
> +
> +	/* release port reset */
> +	val = readl(priv->base + CKCTRL);
> +	val &= ~CKCTRL_P0_RESET;
> +	writel(val, priv->base + CKCTRL);
> +
> +	/* wait until PLL is ready */
> +	if (priv->data->is_ready_high)
> +		ret = readl_poll_timeout(priv->base + CKCTRL, val,
> +					 (val & CKCTRL_P0_READY), 200, 400);
> +	else
> +		ret = readl_poll_timeout(priv->base + CKCTRL, val,
> +					 !(val & CKCTRL_P0_READY), 200, 400);
> +	if (ret) {
> +		dev_err(priv->dev, "Failed to check whether PHY PLL is ready\n");
> +		goto out_disable_clock;
> +	}
> +
> +	return 0;
> +
> +out_disable_clock:
> +	/* assert port reset */
> +	val = readl(priv->base + CKCTRL);
> +	val |= CKCTRL_P0_RESET;
> +	writel(val, priv->base + CKCTRL);
> +
> +	/* disable reference clock for PHY */
> +	val = readl(priv->base + CKCTRL);
> +	val &= ~CKCTRL_REF_SSP_EN;
> +	writel(val, priv->base + CKCTRL);

this seems to be repeated patter, why not add a modifyl() helper here..

> +static int uniphier_ahciphy_pxs3_init(struct uniphier_ahciphy_priv *priv)
> +{
> +	int i;
> +	u32 val;
> +
> +	/* setup port parameter */
> +	val = readl(priv->base + TXCTRL0);
> +	val &= ~TXCTRL0_AMP_G3_MASK;
> +	val |= FIELD_PREP(TXCTRL0_AMP_G3_MASK, 0x73);
> +	val &= ~TXCTRL0_AMP_G2_MASK;
> +	val |= FIELD_PREP(TXCTRL0_AMP_G2_MASK, 0x46);
> +	val &= ~TXCTRL0_AMP_G1_MASK;
> +	val |= FIELD_PREP(TXCTRL0_AMP_G1_MASK, 0x42);
> +	writel(val, priv->base + TXCTRL0);
> +
> +	val = readl(priv->base + TXCTRL1);
> +	val &= ~TXCTRL1_DEEMPH_G3_MASK;
> +	val |= FIELD_PREP(TXCTRL1_DEEMPH_G3_MASK, 0x23);
> +	val &= ~TXCTRL1_DEEMPH_G2_MASK;
> +	val |= FIELD_PREP(TXCTRL1_DEEMPH_G2_MASK, 0x05);
> +	val &= ~TXCTRL1_DEEMPH_G1_MASK;
> +	val |= FIELD_PREP(TXCTRL1_DEEMPH_G1_MASK, 0x05);
> +
> +	val = readl(priv->base + RXCTRL);
> +	val &= ~RXCTRL_LOS_LVL_MASK;
> +	val |= FIELD_PREP(RXCTRL_LOS_LVL_MASK, 0x9);
> +	val &= ~RXCTRL_LOS_BIAS_MASK;
> +	val |= FIELD_PREP(RXCTRL_LOS_BIAS_MASK, 0x2);
> +	val &= ~RXCTRL_RX_EQ_MASK;
> +	val |= FIELD_PREP(RXCTRL_RX_EQ_MASK, 0x1);
> +
> +	/* dummy read 25 times */

why?

> +static int uniphier_ahciphy_init(struct phy *phy)
> +{
> +	struct uniphier_ahciphy_priv *priv = phy_get_drvdata(phy);
> +	int ret;
> +
> +	ret = clk_prepare_enable(priv->clk_parent);
> +	if (ret)
> +		return ret;
> +
> +	ret = reset_control_deassert(priv->rst_parent);
> +	if (ret)
> +		goto out_clk_disable;
> +
> +	if (priv->data->init) {
> +		ret = priv->data->init(priv);
> +		if (ret)
> +			goto out_rst_assert;
> +	}
> +
> +	return ret;

return 0?

> +static const struct uniphier_ahciphy_soc_data uniphier_pxs2_data = {
> +	.init = NULL,

Isn't this superfluous ?
Kunihiko Hayashi July 14, 2020, 9:10 a.m. UTC | #2 
Hi Vinod,

On 2020/07/13 14:05, Vinod Koul wrote:
> On 30-06-20, 17:59, Kunihiko Hayashi wrote:
> 
>> +++ b/drivers/phy/socionext/phy-uniphier-ahci.c
>> @@ -0,0 +1,335 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * phy-uniphier-ahci.c - PHY driver for UniPhier AHCI controller
>> + * Copyright 2016-2018, Socionext Inc.
> 
> we are in 2020 now!

Oops, I'll adjust it.

>> +static int uniphier_ahciphy_pxs2_power_on(struct uniphier_ahciphy_priv *priv)
>> +{
>> +	int ret;
>> +	u32 val;
>> +
>> +	/* enable reference clock for PHY */
>> +	val = readl(priv->base + CKCTRL);
>> +	val |= CKCTRL_REF_SSP_EN;
>> +	writel(val, priv->base + CKCTRL);
>> +
>> +	/* release port reset */
>> +	val = readl(priv->base + CKCTRL);
>> +	val &= ~CKCTRL_P0_RESET;
>> +	writel(val, priv->base + CKCTRL);
>> +
>> +	/* wait until PLL is ready */
>> +	if (priv->data->is_ready_high)
>> +		ret = readl_poll_timeout(priv->base + CKCTRL, val,
>> +					 (val & CKCTRL_P0_READY), 200, 400);
>> +	else
>> +		ret = readl_poll_timeout(priv->base + CKCTRL, val,
>> +					 !(val & CKCTRL_P0_READY), 200, 400);
>> +	if (ret) {
>> +		dev_err(priv->dev, "Failed to check whether PHY PLL is ready\n");
>> +		goto out_disable_clock;
>> +	}
>> +
>> +	return 0;
>> +
>> +out_disable_clock:
>> +	/* assert port reset */
>> +	val = readl(priv->base + CKCTRL);
>> +	val |= CKCTRL_P0_RESET;
>> +	writel(val, priv->base + CKCTRL);
>> +
>> +	/* disable reference clock for PHY */
>> +	val = readl(priv->base + CKCTRL);
>> +	val &= ~CKCTRL_REF_SSP_EN;
>> +	writel(val, priv->base + CKCTRL);
> 
> this seems to be repeated patter, why not add a modifyl() helper here..

Hmm, I try to add helpers for modifying P0_RESET and REF_SSP_EN bits.

> 
>> +static int uniphier_ahciphy_pxs3_init(struct uniphier_ahciphy_priv *priv)
>> +{
>> +	int i;
>> +	u32 val;
>> +
>> +	/* setup port parameter */
>> +	val = readl(priv->base + TXCTRL0);
>> +	val &= ~TXCTRL0_AMP_G3_MASK;
>> +	val |= FIELD_PREP(TXCTRL0_AMP_G3_MASK, 0x73);
>> +	val &= ~TXCTRL0_AMP_G2_MASK;
>> +	val |= FIELD_PREP(TXCTRL0_AMP_G2_MASK, 0x46);
>> +	val &= ~TXCTRL0_AMP_G1_MASK;
>> +	val |= FIELD_PREP(TXCTRL0_AMP_G1_MASK, 0x42);
>> +	writel(val, priv->base + TXCTRL0);
>> +
>> +	val = readl(priv->base + TXCTRL1);
>> +	val &= ~TXCTRL1_DEEMPH_G3_MASK;
>> +	val |= FIELD_PREP(TXCTRL1_DEEMPH_G3_MASK, 0x23);
>> +	val &= ~TXCTRL1_DEEMPH_G2_MASK;
>> +	val |= FIELD_PREP(TXCTRL1_DEEMPH_G2_MASK, 0x05);
>> +	val &= ~TXCTRL1_DEEMPH_G1_MASK;
>> +	val |= FIELD_PREP(TXCTRL1_DEEMPH_G1_MASK, 0x05);
>> +
>> +	val = readl(priv->base + RXCTRL);
>> +	val &= ~RXCTRL_LOS_LVL_MASK;
>> +	val |= FIELD_PREP(RXCTRL_LOS_LVL_MASK, 0x9);
>> +	val &= ~RXCTRL_LOS_BIAS_MASK;
>> +	val |= FIELD_PREP(RXCTRL_LOS_BIAS_MASK, 0x2);
>> +	val &= ~RXCTRL_RX_EQ_MASK;
>> +	val |= FIELD_PREP(RXCTRL_RX_EQ_MASK, 0x1);
>> +
>> +	/* dummy read 25 times */
> 
> why?

According to the specification document,
these 25 read accesses make a wait time for the phy to stablize.
I'll add the reason as comment.

> 
>> +static int uniphier_ahciphy_init(struct phy *phy)
>> +{
>> +	struct uniphier_ahciphy_priv *priv = phy_get_drvdata(phy);
>> +	int ret;
>> +
>> +	ret = clk_prepare_enable(priv->clk_parent);
>> +	if (ret)
>> +		return ret;
>> +
>> +	ret = reset_control_deassert(priv->rst_parent);
>> +	if (ret)
>> +		goto out_clk_disable;
>> +
>> +	if (priv->data->init) {
>> +		ret = priv->data->init(priv);
>> +		if (ret)
>> +			goto out_rst_assert;
>> +	}
>> +
>> +	return ret;
> 
> return 0?

Yes, I'll fix it.

> 
>> +static const struct uniphier_ahciphy_soc_data uniphier_pxs2_data = {
>> +	.init = NULL,
> 
> Isn't this superfluous ?

Indeed, this can be removed.

Thank you,

---
Best Regards
Kunihiko Hayashi