[PATCH v5 2/5] phy: stm32: Add support for STM32MP25 COMBOPHY.

Christian Bruel christian.bruel at foss.st.com
Mon Sep 9 01:40:44 PDT 2024


Hi,

On 9/6/24 15:44, Philipp Zabel wrote:
> Hi,
> 
> On Di, 2024-09-03 at 14:13 +0200, Christian Bruel wrote:
>> Addition of the COMBOPHY driver found on STM32MP25 platforms
>>
>> This single lane PHY is shared (exclusive) between the USB3 and PCIE
>> controllers.
>> Supports 5Gbit/s for PCIE gen2 or 2.5Gbit/s for PCIE gen1.
>>
>> Supports wakeup-source capability to wakeup system using remote-wakeup
>> capable USB device
>>
>> Signed-off-by: Christian Bruel <christian.bruel at foss.st.com>
>> ---
>>   drivers/phy/st/Kconfig              |  11 +
>>   drivers/phy/st/Makefile             |   1 +
>>   drivers/phy/st/phy-stm32-combophy.c | 590 ++++++++++++++++++++++++++++
>>   3 files changed, 602 insertions(+)
>>   create mode 100644 drivers/phy/st/phy-stm32-combophy.c
>>
> [...]
>> diff --git a/drivers/phy/st/phy-stm32-combophy.c b/drivers/phy/st/phy-stm32-combophy.c
>> new file mode 100644
>> index 000000000000..305ba124d092
>> --- /dev/null
>> +++ b/drivers/phy/st/phy-stm32-combophy.c
>> @@ -0,0 +1,590 @@
> [...]
>> +static int stm32_combophy_pll_init(struct stm32_combophy *combophy)
>> +{
>> +	int ret;
>> +	u32 refclksel, pllmult, propcntrl, val;
>> +	u32 clk_rate;
>> +	struct clk *clk;
>> +
>> +	if (combophy->have_pad_clk)
>> +		clk = combophy->clks[PAD_CLK].clk;
>> +	else
>> +		clk = combophy->clks[KER_CLK].clk;
>> +
>> +	clk_rate = clk_get_rate(clk);
>> +
>> +	reset_control_assert(combophy->phy_reset);
>> +
>> +	dev_dbg(combophy->dev, "%s pll init rate %d\n",
>> +		combophy->have_pad_clk ? "External" : "Ker", clk_rate);
>> +
>> +	/*
>> +	 * vddcombophy is interconnected with vddcore. Isolation bit should be unset
>> +	 * before using the ComboPHY.
>> +	 */
>> +	regmap_update_bits(combophy->regmap, SYSCFG_COMBOPHY_CR2,
>> +			   SYSCFG_COMBOPHY_CR2_ISO_DIS, SYSCFG_COMBOPHY_CR2_ISO_DIS);
>> +
>> +	if (combophy->type != PHY_TYPE_PCIE)
>> +		regmap_update_bits(combophy->regmap, SYSCFG_COMBOPHY_CR1,
>> +				   SYSCFG_COMBOPHY_CR1_REFSSPEN, SYSCFG_COMBOPHY_CR1_REFSSPEN);
> 
> Could the multiple accesses to SYSCFG_COMBOPHY_CR1 be consolidated into
> a single regmap_update_bits()?

yes, thanks

> 
>> +
>> +	if (combophy->type == PHY_TYPE_PCIE && !combophy->have_pad_clk)
>> +		regmap_update_bits(combophy->regmap, SYSCFG_PCIEPRGCR,
>> +				   STM32MP25_PCIEPRGCR_EN, STM32MP25_PCIEPRGCR_EN);
>> +
>> +	if (of_property_present(combophy->dev->of_node, "st,ssc-on")) {
>> +		dev_dbg(combophy->dev, "Enabling clock with SSC\n");
>> +		regmap_update_bits(combophy->regmap, SYSCFG_COMBOPHY_CR1,
>> +				   SYSCFG_COMBOPHY_CR1_SSCEN, SYSCFG_COMBOPHY_CR1_SSCEN);
>> +	}
>> +
>> +	if (!of_property_read_u32(combophy->dev->of_node, "st,rx-equalizer", &val)) {
>> +		dev_dbg(combophy->dev, "Set RX equalizer %u\n", val);
>> +		if (val > SYSCFG_COMBOPHY_CR4_RX0_EQ) {
>> +			dev_err(combophy->dev, "Invalid value %u for rx0 equalizer\n", val);
> 
> This path looks like it should deassert the phy_reset as well.

Ack

> 
>> +			return -EINVAL;
>> +		}
>> +
>> +		regmap_update_bits(combophy->regmap, SYSCFG_COMBOPHY_CR4,
>> +			   SYSCFG_COMBOPHY_CR4_RX0_EQ, val);
>> +	}
>> +
>> +	if (combophy->type == PHY_TYPE_PCIE) {
>> +		ret = stm32_impedance_tune(combophy);
>> +		if (ret) {
>> +			reset_control_deassert(combophy->phy_reset);
>> +			goto out;
>> +		}
>> +
>> +		regmap_update_bits(combophy->regmap, SYSCFG_COMBOPHY_CR1,
>> +				   SYSCFG_COMBOPHY_CR1_REFUSEPAD,
>> +				   combophy->have_pad_clk ? SYSCFG_COMBOPHY_CR1_REFUSEPAD : 0);
>> +	}
>> +
>> +	switch (clk_rate) {
>> +	case 100000000:
>> +		pllmult = MPLLMULT_100;
>> +		refclksel = REFCLKSEL_0;
>> +		propcntrl = 0x8u << 4;
>> +		break;
>> +	case 19200000:
>> +		pllmult = MPLLMULT_19_2;
>> +		refclksel = REFCLKSEL_1;
>> +		propcntrl = 0x8u << 4;
>> +		break;
>> +	case 25000000:
>> +		pllmult = MPLLMULT_25;
>> +		refclksel = REFCLKSEL_0;
>> +		propcntrl = 0xeu << 4;
>> +		break;
>> +	case 24000000:
>> +		pllmult = MPLLMULT_24;
>> +		refclksel = REFCLKSEL_1;
>> +		propcntrl = 0xeu << 4;
>> +		break;
>> +	case 20000000:
>> +		pllmult = MPLLMULT_20;
>> +		refclksel = REFCLKSEL_0;
>> +		propcntrl = 0xeu << 4;
>> +		break;
>> +	default:
>> +		dev_err(combophy->dev, "Invalid rate 0x%x\n", clk_rate);
>> +		reset_control_deassert(combophy->phy_reset);
>> +		ret = -EINVAL;
>> +		goto out;
>> +	};
>> +
>> +	regmap_update_bits(combophy->regmap, SYSCFG_COMBOPHY_CR1,
>> +			   SYSCFG_COMBOPHY_CR1_REFCLKDIV2, REFCLDIV_0);
>> +	regmap_update_bits(combophy->regmap, SYSCFG_COMBOPHY_CR1,
>> +			   SYSCFG_COMBOPHY_CR1_REFCLKSEL, refclksel);
>> +	regmap_update_bits(combophy->regmap, SYSCFG_COMBOPHY_CR1,
>> +			   SYSCFG_COMBOPHY_CR1_MPLLMULT, pllmult);
>> +
>> +	/*
>> +	 * Force elasticity buffer to be tuned for the reference clock as
>> +	 * the separated clock model is not supported
>> +	 */
>> +	regmap_update_bits(combophy->regmap, SYSCFG_COMBOPHY_CR5,
>> +			   SYSCFG_COMBOPHY_CR5_COMMON_CLOCKS, SYSCFG_COMBOPHY_CR5_COMMON_CLOCKS);
>> +
>> +	reset_control_deassert(combophy->phy_reset);
>> +
>> +	ret = regmap_read_poll_timeout(combophy->regmap, SYSCFG_COMBOPHY_SR, val,
>> +				       !(val & STM32MP25_PIPE0_PHYSTATUS),
>> +				       10, 1000);
>> +	if (ret) {
>> +		dev_err(combophy->dev, "timeout, cannot lock PLL\n");
>> +		goto out;
>> +	}
>> +
>> +	if (combophy->type == PHY_TYPE_PCIE) {
>> +		val = readl_relaxed(combophy->base + COMBOPHY_SUP_ANA_MPLL_LOOP_CTL);
>> +		val &= ~COMBOPHY_PROP_CNTRL;
>> +		val |= propcntrl;
>> +		writel_relaxed(val, combophy->base + COMBOPHY_SUP_ANA_MPLL_LOOP_CTL);
>> +	}
>> +
>> +	return 0;
>> +
>> +out:
>> +	if (combophy->type == PHY_TYPE_PCIE && !combophy->have_pad_clk)
>> +		regmap_update_bits(combophy->regmap, SYSCFG_PCIEPRGCR,
>> +				   STM32MP25_PCIEPRGCR_EN, 0);
>> +
>> +	if (combophy->type != PHY_TYPE_PCIE)
>> +		regmap_update_bits(combophy->regmap, SYSCFG_COMBOPHY_CR1,
>> +				   SYSCFG_COMBOPHY_CR1_REFSSPEN, 0);
>> +
>> +	regmap_update_bits(combophy->regmap, SYSCFG_COMBOPHY_CR2,
>> +			   SYSCFG_COMBOPHY_CR2_ISO_DIS, 0);
>> +
>> +	return ret;
>> +}
>> +
> [...]
>> +
>> +static int stm32_combophy_probe(struct platform_device *pdev)
>> +{
>> +	struct stm32_combophy *combophy;
>> +	struct device *dev = &pdev->dev;
>> +	struct phy_provider *phy_provider;
>> +	int ret, irq;
>> +
>> +	combophy = devm_kzalloc(dev, sizeof(*combophy), GFP_KERNEL);
>> +	if (!combophy)
>> +		return -ENOMEM;
>> +
>> +	combophy->dev = dev;
>> +
>> +	dev_set_drvdata(dev, combophy);
>> +
>> +	combophy->base = devm_platform_ioremap_resource(pdev, 0);
>> +	if (IS_ERR(combophy->base))
>> +		return PTR_ERR(combophy->base);
>> +
>> +	if (stm32_combophy_get_clocks(combophy))
>> +		return ret;
>> +
>> +	combophy->phy_reset = devm_reset_control_get(dev, "phy");
> 
> Please use devm_reset_control_get_exclusive() directly.

OK,

thanks,
Christian
> 
> regards
> Philipp



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