[PATCH v3 0/5] Add STM32MP25 USB3/PCIE COMBOPHY driver

[PATCH v3 0/5] Add STM32MP25 USB3/PCIE COMBOPHY driver

[Christian Bruel]

This patch series adds USB3/PCIE COMBOPHY driver for the STM32MP25 SoC from
STMicrolectronics, respective yaml schema and enable for the stm32mp257f-ev1
device into which it is used for PCIe.

Changes in v3:
Address comments from Rob and Krzysztof:
   - Reorder MAINTAINERS patch
   - Drop wakeup-source from bindings (should be generic)

Changes in v2:
   - Reorder entries
   - Rename clock_names and reset_names bindings
   - Rename and clarify rx-equalizer binding 

Christian Bruel (5):
  dt-bindings: phy: Add STM32MP25 COMBOPHY bindings
  phy: stm32: Add support for STM32MP25 COMBOPHY.
  MAINTAINERS: add entry for ST STM32MP25 COMBOPHY driver
  arm64: dts: st: Add combophy node on stm32mp251
  arm64: dts: st: Enable COMBOPHY on the stm32mp257f-ev1 board

 .../bindings/phy/st,stm32-combophy.yaml       | 144 +++++
 MAINTAINERS                                   |   6 +
 arch/arm64/boot/dts/st/stm32mp251.dtsi        |  17 +
 arch/arm64/boot/dts/st/stm32mp257f-ev1.dts    |  14 +
 drivers/phy/st/Kconfig                        |  11 +
 drivers/phy/st/Makefile                       |   1 +
 drivers/phy/st/phy-stm32-combophy.c           | 607 ++++++++++++++++++
 7 files changed, 800 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/phy/st,stm32-combophy.yaml
 create mode 100644 drivers/phy/st/phy-stm32-combophy.c

-- 
2.34.1

[PATCH 1/5] dt-bindings: phy: Add STM32MP25 COMBOPHY bindings

[Christian Bruel]

Document the bindings for STM32 COMBOPHY interface, used to support
the PCIe and USB3 stm32mp25 drivers.
Following entries can be used to tune caracterisation parameters
 - st,output-micro-ohms and st,output-vswing-microvolt bindings entries
to tune the impedance and voltage swing using discrete simulation results
 - st,rx-equalizer register to set the internal rx equalizer filter value.

Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Christian Bruel <christian.bruel@foss.st.com>
---
 .../bindings/phy/st,stm32-combophy.yaml       | 144 ++++++++++++++++++
 1 file changed, 144 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/phy/st,stm32-combophy.yaml

diff --git a/Documentation/devicetree/bindings/phy/st,stm32-combophy.yaml b/Documentation/devicetree/bindings/phy/st,stm32-combophy.yaml
new file mode 100644
index 000000000000..c33a843b83a3
--- /dev/null
+++ b/Documentation/devicetree/bindings/phy/st,stm32-combophy.yaml
@@ -0,0 +1,144 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/phy/st,stm32-combophy.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: STMicroelectronics STM32MP25 USB3/PCIe COMBOPHY
+
+maintainers:
+  - Christian Bruel <christian.bruel@foss.st.com>
+
+description:
+  Single lane PHY shared (exclusive) between the USB3 and PCIe controllers.
+  Supports 5Gbit/s for USB3 and PCIe gen2 or 2.5Gbit/s for PCIe gen1.
+
+properties:
+  compatible:
+    const: st,stm32mp25-combophy
+
+  reg:
+    maxItems: 1
+
+  "#phy-cells":
+    const: 1
+    description: |
+      The cells contain the following arguments.
+
+      - description: The PHY type
+          enum:
+            - PHY_TYPE_USB3
+            - PHY_TYPE_PCIE
+
+  clocks:
+    minItems: 2
+    items:
+      - description: apb Bus clock mandatory to access registers.
+      - description: ker Internal RCC reference clock for USB3 or PCIe
+      - description: pad Optional on board clock input for PCIe only. Typically an
+                     external 100Mhz oscillator wired on dedicated CLKIN pad. Used as reference
+                     clock input instead of the ker
+
+  clock-names:
+    minItems: 2
+    items:
+      - const: apb
+      - const: ker
+      - const: pad
+
+  resets:
+    maxItems: 1
+
+  reset-names:
+    const: phy
+
+  power-domains:
+    maxItems: 1
+
+  wakeup-source: true
+
+  interrupts:
+    maxItems: 1
+    description: interrupt used for wakeup
+
+  access-controllers:
+    minItems: 1
+    maxItems: 2
+
+  st,syscfg:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description: Phandle to the SYSCON entry required for configuring PCIe
+      or USB3.
+
+  st,ssc-on:
+    type: boolean
+    description:
+      A boolean property whose presence indicates that the SSC for common clock
+      needs to be set.
+
+  st,rx-equalizer:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    minimum: 0
+    maximum: 7
+    default: 2
+    description:
+      A 3 bit value to tune the RX fixed equalizer setting for optimal eye compliance
+
+  st,output-micro-ohms:
+    minimum: 3999000
+    maximum: 6090000
+    default: 4968000
+    description:
+      A value property to tune the Single Ended Output Impedance, simulations results
+      at 25C for a VDDP=0.8V. The hardware accepts discrete values in this range.
+
+  st,output-vswing-microvolt:
+    minimum: 442000
+    maximum: 803000
+    default: 803000
+    description:
+      A value property in microvolt to tune the Single Ended Output Voltage Swing to change the
+      Vlo, Vhi for a VDDP = 0.8V. The hardware accepts discrete values in this range.
+
+required:
+  - compatible
+  - reg
+  - st,syscfg
+  - '#phy-cells'
+  - resets
+  - reset-names
+  - clocks
+  - clock-names
+
+allOf:
+  - if:
+      required:
+        - wakeup-source
+    then:
+      anyOf:
+        - required: [interrupts]
+        - required: [interrupts-extended]
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/st,stm32mp25-rcc.h>
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    #include <dt-bindings/reset/st,stm32mp25-rcc.h>
+
+    combophy: phy@480c0000 {
+        compatible = "st,stm32mp25-combophy";
+        reg = <0x480c0000 0x1000>;
+        #phy-cells = <1>;
+        clocks = <&rcc CK_BUS_USB3PCIEPHY>, <&rcc CK_KER_USB3PCIEPHY>;
+        clock-names = "apb", "ker";
+        resets = <&rcc USB3PCIEPHY_R>;
+        reset-names = "phy";
+        st,syscfg = <&syscfg>;
+        access-controllers = <&rifsc 67>;
+        power-domains = <&CLUSTER_PD>;
+        wakeup-source;
+        interrupts-extended = <&exti1 45 IRQ_TYPE_EDGE_FALLING>;
+    };
+...
-- 
2.34.1

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

[Christian Bruel]

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@foss.st.com>
---
 drivers/phy/st/Kconfig              |  11 +
 drivers/phy/st/Makefile             |   1 +
 drivers/phy/st/phy-stm32-combophy.c | 607 ++++++++++++++++++++++++++++
 3 files changed, 619 insertions(+)
 create mode 100644 drivers/phy/st/phy-stm32-combophy.c

diff --git a/drivers/phy/st/Kconfig b/drivers/phy/st/Kconfig
index 3fc3d0781fb8..304614b6dabf 100644
--- a/drivers/phy/st/Kconfig
+++ b/drivers/phy/st/Kconfig
@@ -33,6 +33,17 @@ config PHY_STIH407_USB
 	  Enable this support to enable the picoPHY device used by USB2
 	  and USB3 controllers on STMicroelectronics STiH407 SoC families.
 
+config PHY_STM32_COMBOPHY
+	tristate "STMicroelectronics COMBOPHY driver for STM32MP25"
+	depends on ARCH_STM32 || COMPILE_TEST
+	select GENERIC_PHY
+	help
+	  Enable this to support the COMBOPHY device used by USB3 or PCIe
+	  controllers on STMicroelectronics STM32MP25 SoC.
+	  This driver controls the COMBOPHY block to generate the PCIe 100Mhz
+	  reference clock from either the external clock generator or HSE
+	  internal SoC clock source.
+
 config PHY_STM32_USBPHYC
 	tristate "STMicroelectronics STM32 USB HS PHY Controller driver"
 	depends on ARCH_STM32 || COMPILE_TEST
diff --git a/drivers/phy/st/Makefile b/drivers/phy/st/Makefile
index c862dd937b64..cb80e954ea9f 100644
--- a/drivers/phy/st/Makefile
+++ b/drivers/phy/st/Makefile
@@ -3,4 +3,5 @@ obj-$(CONFIG_PHY_MIPHY28LP) 		+= phy-miphy28lp.o
 obj-$(CONFIG_PHY_ST_SPEAR1310_MIPHY)	+= phy-spear1310-miphy.o
 obj-$(CONFIG_PHY_ST_SPEAR1340_MIPHY)	+= phy-spear1340-miphy.o
 obj-$(CONFIG_PHY_STIH407_USB)		+= phy-stih407-usb.o
+obj-$(CONFIG_PHY_STM32_COMBOPHY)	+= phy-stm32-combophy.o
 obj-$(CONFIG_PHY_STM32_USBPHYC) 	+= phy-stm32-usbphyc.o
diff --git a/drivers/phy/st/phy-stm32-combophy.c b/drivers/phy/st/phy-stm32-combophy.c
new file mode 100644
index 000000000000..7cd4193b0277
--- /dev/null
+++ b/drivers/phy/st/phy-stm32-combophy.c
@@ -0,0 +1,607 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * STMicroelectronics COMBOPHY STM32MP25 Controller driver.
+ *
+ * Copyright (C) 2024 STMicroelectronics
+ * Author: Christian Bruel <christian.bruel@foss.st.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/mfd/syscon.h>
+#include <linux/platform_device.h>
+#include <linux/phy/phy.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <dt-bindings/phy/phy.h>
+
+#define SYSCFG_COMBOPHY_CR1 0x4C00
+#define SYSCFG_COMBOPHY_CR2 0x4C04
+#define SYSCFG_COMBOPHY_CR4 0x4C0C
+#define SYSCFG_COMBOPHY_CR5 0x4C10
+#define SYSCFG_COMBOPHY_SR  0x4C14
+#define SYSCFG_PCIEPRGCR    0x6080
+
+/* SYSCFG PCIEPRGCR */
+#define STM32MP25_PCIEPRGCR_EN	  BIT(0)
+#define STM32MP25_PCIEPRG_IMPCTRL_OHM     GENMASK(3, 1)
+#define STM32MP25_PCIEPRG_IMPCTRL_VSWING  GENMASK(5, 4)
+
+/* SYSCFG SYSCFG_COMBOPHY_SR */
+#define STM32MP25_PIPE0_PHYSTATUS BIT(1)
+
+/* SYSCFG CR1 */
+#define SYSCFG_COMBOPHY_CR1_REFUSEPAD BIT(0)
+#define SYSCFG_COMBOPHY_CR1_MPLLMULT GENMASK(7, 1)
+#define SYSCFG_COMBOPHY_CR1_REFCLKSEL GENMASK(16, 8)
+#define SYSCFG_COMBOPHY_CR1_REFCLKDIV2 BIT(17)
+#define SYSCFG_COMBOPHY_CR1_REFSSPEN BIT(18)
+#define SYSCFG_COMBOPHY_CR1_SSCEN BIT(19)
+
+/* SYSCFG CR4 */
+#define SYSCFG_COMBOPHY_CR4_RX0_EQ GENMASK(2, 0)
+
+#define MPLLMULT_19_2 (0x02u << 1)
+#define MPLLMULT_20   (0x7Du << 1)
+#define MPLLMULT_24   (0x68u << 1)
+#define MPLLMULT_25   (0x64u << 1)
+#define MPLLMULT_26   (0x60u << 1)
+#define MPLLMULT_38_4 (0x41u << 1)
+#define MPLLMULT_48   (0x6Cu << 1)
+#define MPLLMULT_50   (0x32u << 1)
+#define MPLLMULT_52   (0x30u << 1)
+#define MPLLMULT_100  (0x19u << 1)
+
+#define REFCLKSEL_0   0
+#define REFCLKSEL_1   (0x108u << 8)
+
+#define REFCLDIV_0    0
+
+/* SYSCFG CR2 */
+#define SYSCFG_COMBOPHY_CR2_MODESEL GENMASK(1, 0)
+#define SYSCFG_COMBOPHY_CR2_ISO_DIS BIT(15)
+
+#define COMBOPHY_MODESEL_PCIE 0
+#define COMBOPHY_MODESEL_USB  3
+
+/* SYSCFG CR5 */
+#define SYSCFG_COMBOPHY_CR5_COMMON_CLOCKS BIT(12)
+
+#define COMBOPHY_SUP_ANA_MPLL_LOOP_CTL 0xC0
+#define COMBOPHY_PROP_CNTRL GENMASK(7, 4)
+
+struct stm32_combophy {
+	struct phy *phy;
+	struct regmap *regmap;
+	struct device *dev;
+	void __iomem *base;
+	struct reset_control *phy_reset;
+	struct clk *phy_clk;
+	struct clk *pad_clk;
+	struct clk *ker_clk;
+	unsigned int type;
+	bool is_init;
+	int irq_wakeup;
+};
+
+struct clk_impedance  {
+	u32 microohm;
+	u32 vswing[4];
+};
+
+/*
+ * lookup table to hold the settings needed for a ref clock frequency
+ * impedance, the offset is used to set the IMP_CTL and DE_EMP bit of the
+ * PRG_IMP_CTRL register
+ */
+static const struct clk_impedance imp_lookup[] = {
+	{ 6090000, { 442000, 564000, 684000, 802000 } },
+	{ 5662000, { 528000, 621000, 712000, 803000 } },
+	{ 5292000, { 491000, 596000, 700000, 802000 } },
+	{ 4968000, { 558000, 640000, 722000, 803000 } },
+	{ 4684000, { 468000, 581000, 692000, 802000 } },
+	{ 4429000, { 554000, 613000, 717000, 803000 } },
+	{ 4204000, { 511000, 609000, 706000, 802000 } },
+	{ 3999000, { 571000, 648000, 726000, 803000 } }
+};
+
+static int stm32_impedance_tune(struct stm32_combophy *combophy)
+{
+	u8 imp_size = ARRAY_SIZE(imp_lookup);
+	u8 vswing_size = ARRAY_SIZE(imp_lookup[0].vswing);
+	u8 imp_of, vswing_of;
+	u32 max_imp = imp_lookup[0].microohm;
+	u32 min_imp = imp_lookup[imp_size - 1].microohm;
+	u32 max_vswing = imp_lookup[imp_size - 1].vswing[vswing_size - 1];
+	u32 min_vswing = imp_lookup[0].vswing[0];
+	u32 val;
+
+	if (!of_property_read_u32(combophy->dev->of_node, "st,output-micro-ohms", &val)) {
+		if (val < min_imp || val > max_imp) {
+			dev_err(combophy->dev, "Invalid value %u for output ohm\n", val);
+			return -EINVAL;
+		}
+
+		for (imp_of = 0 ; imp_of < ARRAY_SIZE(imp_lookup); imp_of++)
+			if (imp_lookup[imp_of].microohm <= val)
+				break;
+
+		dev_dbg(combophy->dev, "Set %u micro-ohms output impedance\n",
+			imp_lookup[imp_of].microohm);
+
+		regmap_update_bits(combophy->regmap, SYSCFG_PCIEPRGCR,
+				   STM32MP25_PCIEPRG_IMPCTRL_OHM,
+				   FIELD_PREP(STM32MP25_PCIEPRG_IMPCTRL_OHM, imp_of));
+	} else {
+		regmap_read(combophy->regmap, SYSCFG_PCIEPRGCR, &val);
+		imp_of = FIELD_GET(STM32MP25_PCIEPRG_IMPCTRL_OHM, val);
+	}
+
+	if (!of_property_read_u32(combophy->dev->of_node, "st,output-vswing-microvolt", &val)) {
+		if (val < min_vswing || val > max_vswing) {
+			dev_err(combophy->dev, "Invalid value %u for output vswing\n", val);
+			return -EINVAL;
+		}
+
+		for (vswing_of = 0 ; vswing_of < ARRAY_SIZE(imp_lookup[imp_of].vswing); vswing_of++)
+			if (imp_lookup[imp_of].vswing[vswing_of] >= val)
+				break;
+
+		dev_dbg(combophy->dev, "Set %u microvolt swing\n",
+			 imp_lookup[imp_of].vswing[vswing_of]);
+
+		regmap_update_bits(combophy->regmap, SYSCFG_PCIEPRGCR,
+				   STM32MP25_PCIEPRG_IMPCTRL_VSWING,
+				   FIELD_PREP(STM32MP25_PCIEPRG_IMPCTRL_VSWING, vswing_of));
+	}
+
+	return 0;
+}
+
+static int stm32_combophy_pll_init(struct stm32_combophy *combophy)
+{
+	int ret;
+	u32 refclksel, pllmult, propcntrl, val;
+	u32 clk_rate;
+
+	if (combophy->pad_clk)
+		clk_rate = clk_get_rate(combophy->pad_clk);
+	else
+		clk_rate = clk_get_rate(combophy->ker_clk);
+
+	reset_control_assert(combophy->phy_reset);
+
+	dev_dbg(combophy->dev, "%s pll init rate %d\n",
+		combophy->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);
+
+	if (combophy->type == PHY_TYPE_PCIE && !combophy->pad_clk)
+		regmap_update_bits(combophy->regmap, SYSCFG_PCIEPRGCR,
+				   STM32MP25_PCIEPRGCR_EN, STM32MP25_PCIEPRGCR_EN);
+
+	if (of_property_read_bool(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);
+			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->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->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 struct phy *stm32_combophy_xlate(struct device *dev,
+					const struct of_phandle_args *args)
+{
+	struct stm32_combophy *combophy = dev_get_drvdata(dev);
+	unsigned int type;
+
+	if (args->args_count != 1) {
+		dev_err(dev, "invalid number of cells in 'phy' property\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	type = args->args[0];
+	if (type != PHY_TYPE_USB3 && type != PHY_TYPE_PCIE) {
+		dev_err(dev, "unsupported device type: %d\n", type);
+		return ERR_PTR(-EINVAL);
+	}
+
+	if (combophy->pad_clk && type != PHY_TYPE_PCIE) {
+		dev_err(dev, "Invalid use of clk_pad for USB3 mode\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	combophy->type = type;
+
+	return combophy->phy;
+}
+
+static int stm32_combophy_set_mode(struct stm32_combophy *combophy)
+{
+	int type = combophy->type;
+	u32 val;
+
+	switch (type) {
+	case PHY_TYPE_PCIE:
+		dev_dbg(combophy->dev, "setting PCIe ComboPHY\n");
+		val = COMBOPHY_MODESEL_PCIE;
+		break;
+	case PHY_TYPE_USB3:
+		dev_dbg(combophy->dev, "setting USB3 ComboPHY\n");
+		val = COMBOPHY_MODESEL_USB;
+		break;
+	default:
+		dev_err(combophy->dev, "Invalid PHY mode %d\n", type);
+		return -EINVAL;
+	}
+
+	return regmap_update_bits(combophy->regmap, SYSCFG_COMBOPHY_CR2,
+				  SYSCFG_COMBOPHY_CR2_MODESEL, val);
+}
+
+static int stm32_combophy_enable_clocks(struct stm32_combophy *combophy)
+{
+	int ret;
+
+	ret = clk_prepare_enable(combophy->phy_clk);
+	if (ret) {
+		dev_err(combophy->dev, "Core clock enable failed %d\n", ret);
+		return ret;
+	}
+
+	ret = clk_prepare_enable(combophy->ker_clk);
+	if (ret) {
+		dev_err(combophy->dev, "ker_usb3pcie clock enable failed %d\n", ret);
+		clk_disable_unprepare(combophy->phy_clk);
+		return ret;
+	}
+
+	if (combophy->pad_clk) {
+		ret = clk_prepare_enable(combophy->pad_clk);
+		if (ret) {
+			dev_err(combophy->dev, "External clock enable failed %d\n", ret);
+			clk_disable_unprepare(combophy->ker_clk);
+			clk_disable_unprepare(combophy->phy_clk);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static void stm32_combophy_disable_clocks(struct stm32_combophy *combophy)
+{
+	if (combophy->pad_clk)
+		clk_disable_unprepare(combophy->pad_clk);
+	clk_disable_unprepare(combophy->ker_clk);
+	clk_disable_unprepare(combophy->phy_clk);
+}
+
+static int stm32_combophy_suspend_noirq(struct device *dev)
+{
+	struct stm32_combophy *combophy = dev_get_drvdata(dev);
+
+	/*
+	 * Clocks should be turned off since it is not needed for
+	 * wakeup capability. In case usb-remote wakeup is not enabled,
+	 * combo-phy is already turned off by HCD driver using exit callback
+	 */
+	if (combophy->is_init) {
+		stm32_combophy_disable_clocks(combophy);
+
+		/* since wakeup is enabled for ctrl */
+		enable_irq_wake(combophy->irq_wakeup);
+	}
+
+	return 0;
+}
+
+static int stm32_combophy_resume_noirq(struct device *dev)
+{
+	struct stm32_combophy *combophy = dev_get_drvdata(dev);
+	int ret;
+
+	/*
+	 * If clocks was turned off by suspend call for wakeup then needs
+	 * to be turned back ON in resume. In case usb-remote wakeup is not
+	 * enabled, clocks already turned ON by HCD driver using init callback
+	 */
+	if (combophy->is_init) {
+		/* since wakeup was enabled for ctrl */
+		disable_irq_wake(combophy->irq_wakeup);
+
+		ret = stm32_combophy_enable_clocks(combophy);
+		if (ret) {
+			dev_err(dev, "can't enable clocks (%d)\n", ret);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static int stm32_combophy_exit(struct phy *phy)
+{
+	struct stm32_combophy *combophy = phy_get_drvdata(phy);
+	struct device *dev = combophy->dev;
+
+	combophy->is_init = false;
+
+	if (combophy->type == PHY_TYPE_PCIE && !combophy->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);
+
+	stm32_combophy_disable_clocks(combophy);
+
+	pm_runtime_put_noidle(dev);
+
+	return 0;
+}
+
+static int stm32_combophy_init(struct phy *phy)
+{
+	struct stm32_combophy *combophy = phy_get_drvdata(phy);
+	struct device *dev = combophy->dev;
+	int ret;
+
+	pm_runtime_get_noresume(dev);
+
+	ret = stm32_combophy_enable_clocks(combophy);
+	if (ret) {
+		dev_err(dev, "Clock enable failed %d\n", ret);
+		pm_runtime_put_noidle(dev);
+		return ret;
+	}
+
+	ret = stm32_combophy_set_mode(combophy);
+	if (ret) {
+		dev_err(dev, "combophy mode not set\n");
+		stm32_combophy_disable_clocks(combophy);
+		pm_runtime_put_noidle(dev);
+		return ret;
+	}
+
+	ret = stm32_combophy_pll_init(combophy);
+	if (ret) {
+		stm32_combophy_disable_clocks(combophy);
+		pm_runtime_put_noidle(dev);
+		return ret;
+	}
+
+	pm_runtime_disable(dev);
+	pm_runtime_set_active(dev);
+	pm_runtime_enable(dev);
+
+	combophy->is_init = true;
+
+	return ret;
+}
+
+static const struct phy_ops stm32_combophy_phy_data = {
+	.init = stm32_combophy_init,
+	.exit = stm32_combophy_exit,
+	.owner = THIS_MODULE
+};
+
+static irqreturn_t stm32_combophy_irq_wakeup_handler(int irq, void *dev_id)
+{
+	return IRQ_HANDLED;
+}
+
+static int stm32_combophy_probe(struct platform_device *pdev)
+{
+	struct stm32_combophy *combophy;
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+	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);
+
+	combophy->phy_clk = devm_clk_get(dev, "apb");
+	if (IS_ERR(combophy->phy_clk))
+		return dev_err_probe(dev, PTR_ERR(combophy->phy_clk),
+				     "Failed to get PHY clock source\n");
+
+	combophy->ker_clk = devm_clk_get(dev, "ker");
+	if (IS_ERR(combophy->ker_clk))
+		return dev_err_probe(dev, PTR_ERR(combophy->ker_clk),
+				     "Failed to get PHY internal clock source\n");
+
+	combophy->pad_clk = devm_clk_get_optional(dev, "pad");
+	if (IS_ERR(combophy->pad_clk))
+		return dev_err_probe(dev, PTR_ERR(combophy->pad_clk),
+				     "Failed to get PHY external clock source\n");
+
+	combophy->phy_reset = devm_reset_control_get(dev, "phy");
+	if (IS_ERR(combophy->phy_reset))
+		return dev_err_probe(dev, PTR_ERR(combophy->phy_reset),
+				     "Failed to get PHY reset\n");
+
+	combophy->regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
+	if (IS_ERR(combophy->regmap))
+		return dev_err_probe(dev, PTR_ERR(combophy->regmap),
+				     "No syscfg phandle specified\n");
+
+	combophy->phy = devm_phy_create(dev, NULL, &stm32_combophy_phy_data);
+	if (IS_ERR(combophy->phy))
+		return dev_err_probe(dev, PTR_ERR(combophy->phy),
+				     "failed to create PCIe/USB3 ComboPHY\n");
+
+	if (device_property_read_bool(dev, "wakeup-source")) {
+		irq = platform_get_irq(pdev, 0);
+		if (irq < 0)
+			return dev_err_probe(dev, irq, "failed to get IRQ\n");
+		combophy->irq_wakeup = irq;
+
+		ret = devm_request_threaded_irq(dev, combophy->irq_wakeup, NULL,
+						stm32_combophy_irq_wakeup_handler, IRQF_ONESHOT,
+						NULL, NULL);
+		if (ret)
+			return dev_err_probe(dev, ret, "unable to request wake IRQ %d\n",
+						 combophy->irq_wakeup);
+	}
+
+	ret = devm_pm_runtime_enable(dev);
+	if (ret)
+		return dev_err_probe(dev, ret, "Failed to enable pm runtime\n");
+
+	phy_set_drvdata(combophy->phy, combophy);
+
+	phy_provider = devm_of_phy_provider_register(dev, stm32_combophy_xlate);
+
+	return PTR_ERR_OR_ZERO(phy_provider);
+}
+
+static const struct dev_pm_ops stm32_combophy_pm_ops = {
+	NOIRQ_SYSTEM_SLEEP_PM_OPS(stm32_combophy_suspend_noirq,
+				  stm32_combophy_resume_noirq)
+};
+
+static const struct of_device_id stm32_combophy_of_match[] = {
+	{ .compatible = "st,stm32mp25-combophy", },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, stm32_combophy_of_match);
+
+static struct platform_driver stm32_combophy_driver = {
+	.probe = stm32_combophy_probe,
+	.driver = {
+		   .name = "stm32-combophy",
+		   .of_match_table = stm32_combophy_of_match,
+		   .pm = pm_sleep_ptr(&stm32_combophy_pm_ops)
+	}
+};
+
+module_platform_driver(stm32_combophy_driver);
+
+MODULE_AUTHOR("Christian Bruel <christian.bruel@foss.st.com>");
+MODULE_DESCRIPTION("STM32MP25 Combophy USB3/PCIe controller driver");
+MODULE_LICENSE("GPL");
-- 
2.34.1

[PATCH 3/5] MAINTAINERS: add entry for ST STM32MP25 COMBOPHY driver

[Christian Bruel]

Add myself as STM32MP25 COMBOPHY maintainer

Signed-off-by: Christian Bruel <christian.bruel@foss.st.com>
---
 MAINTAINERS | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index f328373463b0..258fb57ccff5 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -21910,6 +21910,12 @@ F:	arch/m68k/kernel/*sun3*
 F:	arch/m68k/sun3*/
 F:	drivers/net/ethernet/i825xx/sun3*
 
+STMICROELECTRONICS STMP32MP25 USB3/PCIE COMBOPHY DRIVER
+M:	Christian Bruel <christian.bruel@foss.st.com>
+S:	Maintained
+F:	Documentation/devicetree/bindings/phy/st,stm32-combophy.yaml
+F:	drivers/phy/st/phy-stm32-combophy.c
+
 SUN4I LOW RES ADC ATTACHED TABLET KEYS DRIVER
 M:	Hans de Goede <hdegoede@redhat.com>
 L:	linux-input@vger.kernel.org
-- 
2.34.1

[PATCH 4/5] arm64: dts: st: Add combophy node on stm32mp251

[Christian Bruel]

Add support for COMBOPHY which is used either by the USB3 and PCIe
controller.
USB3 or PCIe mode is done with phy_set_mode().
PCIe internal reference clock can be generated from the internal clock
source or optionnaly from an external 100Mhz pad.

Signed-off-by: Christian Bruel <christian.bruel@foss.st.com>
---
 arch/arm64/boot/dts/st/stm32mp251.dtsi | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/arch/arm64/boot/dts/st/stm32mp251.dtsi b/arch/arm64/boot/dts/st/stm32mp251.dtsi
index 1167cf63d7e8..0d38763d9317 100644
--- a/arch/arm64/boot/dts/st/stm32mp251.dtsi
+++ b/arch/arm64/boot/dts/st/stm32mp251.dtsi
@@ -7,6 +7,7 @@
 #include <dt-bindings/interrupt-controller/arm-gic.h>
 #include <dt-bindings/reset/st,stm32mp25-rcc.h>
 #include <dt-bindings/regulator/st,stm32mp25-regulator.h>
+#include <dt-bindings/phy/phy.h>
 
 / {
 	#address-cells = <2>;
@@ -518,6 +519,22 @@ i2c8: i2c@46040000 {
 				status = "disabled";
 			};
 
+			combophy: phy@480c0000 {
+				compatible = "st,stm32mp25-combophy";
+				reg = <0x480c0000 0x1000>;
+				#phy-cells = <1>;
+				clocks = <&rcc CK_BUS_USB3PCIEPHY>, <&rcc CK_KER_USB3PCIEPHY>;
+				clock-names = "apb", "ker";
+				resets = <&rcc USB3PCIEPHY_R>;
+				reset-names = "phy";
+				st,syscfg = <&syscfg>;
+				access-controllers = <&rifsc 67>;
+				power-domains = <&CLUSTER_PD>;
+				wakeup-source;
+				interrupts-extended = <&exti1 45 IRQ_TYPE_EDGE_FALLING>;
+				status = "disabled";
+			};
+
 			sdmmc1: mmc@48220000 {
 				compatible = "st,stm32mp25-sdmmc2", "arm,pl18x", "arm,primecell";
 				arm,primecell-periphid = <0x00353180>;
-- 
2.34.1

[PATCH 5/5] arm64: dts: st: Enable COMBOPHY on the stm32mp257f-ev1 board

[Christian Bruel]

Enable the COMBOPHY with external pad clock on stm32mp257f-ev1
board, to be used for the PCIe clock provider.

Signed-off-by: Christian Bruel <christian.bruel@foss.st.com>
---
 arch/arm64/boot/dts/st/stm32mp257f-ev1.dts | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/arch/arm64/boot/dts/st/stm32mp257f-ev1.dts b/arch/arm64/boot/dts/st/stm32mp257f-ev1.dts
index 214191a8322b..bcf84d533cb2 100644
--- a/arch/arm64/boot/dts/st/stm32mp257f-ev1.dts
+++ b/arch/arm64/boot/dts/st/stm32mp257f-ev1.dts
@@ -27,6 +27,14 @@ chosen {
 		stdout-path = "serial0:115200n8";
 	};
 
+	clocks {
+		pad_clk: pad-clk {
+			#clock-cells = <0>;
+			compatible = "fixed-clock";
+			clock-frequency = <100000000>;
+		};
+	};
+
 	memory@80000000 {
 		device_type = "memory";
 		reg = <0x0 0x80000000 0x1 0x0>;
@@ -50,6 +58,12 @@ &arm_wdt {
 	status = "okay";
 };
 
+&combophy {
+	clocks = <&rcc CK_BUS_USB3PCIEPHY>, <&rcc CK_KER_USB3PCIEPHY>, <&pad_clk>;
+	clock-names = "apb", "ker", "pad";
+	status = "okay";
+};
+
 &ethernet2 {
 	pinctrl-names = "default", "sleep";
 	pinctrl-0 = <&eth2_rgmii_pins_a>;
-- 
2.34.1

Re: [PATCH 1/5] dt-bindings: phy: Add STM32MP25 COMBOPHY bindings

[Krzysztof Kozlowski]

On 27/08/2024 14:24, Christian Bruel wrote:
> Document the bindings for STM32 COMBOPHY interface, used to support
> the PCIe and USB3 stm32mp25 drivers.
> Following entries can be used to tune caracterisation parameters
>  - st,output-micro-ohms and st,output-vswing-microvolt bindings entries
> to tune the impedance and voltage swing using discrete simulation results
>  - st,rx-equalizer register to set the internal rx equalizer filter value.
> 
> Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
> Signed-off-by: Christian Bruel <christian.bruel@foss.st.com>

v1? Or v3?

> ---
>  .../bindings/phy/st,stm32-combophy.yaml       | 144 ++++++++++++++++++
>  1 file changed, 144 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/phy/st,stm32-combophy.yaml
> 
> diff --git a/Documentation/devicetree/bindings/phy/st,stm32-combophy.yaml b/Documentation/devicetree/bindings/phy/st,stm32-combophy.yaml
> new file mode 100644
> index 000000000000..c33a843b83a3
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/phy/st,stm32-combophy.yaml

Filename matching compatible.

> @@ -0,0 +1,144 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/phy/st,stm32-combophy.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: STMicroelectronics STM32MP25 USB3/PCIe COMBOPHY
> +
> +maintainers:
> +  - Christian Bruel <christian.bruel@foss.st.com>
> +
> +description:
> +  Single lane PHY shared (exclusive) between the USB3 and PCIe controllers.
> +  Supports 5Gbit/s for USB3 and PCIe gen2 or 2.5Gbit/s for PCIe gen1.
> +
> +properties:
> +  compatible:
> +    const: st,stm32mp25-combophy
> +
> +  reg:
> +    maxItems: 1
> +
> +  "#phy-cells":
> +    const: 1
> +    description: |
> +      The cells contain the following arguments.
> +
> +      - description: The PHY type

That's some sort of mess. Is it schema within description or schema? Why
two descriptions?

> +          enum:
> +            - PHY_TYPE_USB3
> +            - PHY_TYPE_PCIE
> +

...

> +required:
> +  - compatible
> +  - reg
> +  - st,syscfg
> +  - '#phy-cells'
> +  - resets
> +  - reset-names
> +  - clocks
> +  - clock-names
> +
> +allOf:
> +  - if:
> +      required:
> +        - wakeup-source
> +    then:
> +      anyOf:
> +        - required: [interrupts]
> +        - required: [interrupts-extended]
> +

I do not see any improvements.

The tag you received was CONDITIONAL. If you do not apply the comments,
you cannot just apply the tag.

Best regards,
Krzysztof

Re: [PATCH v3 0/5] Add STM32MP25 USB3/PCIE COMBOPHY driver

[Krzysztof Kozlowski]

On 27/08/2024 14:24, Christian Bruel wrote:
> This patch series adds USB3/PCIE COMBOPHY driver for the STM32MP25 SoC from
> STMicrolectronics, respective yaml schema and enable for the stm32mp257f-ev1
> device into which it is used for PCIe.
> 
> Changes in v3:
> Address comments from Rob and Krzysztof:
>    - Reorder MAINTAINERS patch
>    - Drop wakeup-source from bindings (should be generic)

Where? Point me to the exact line being dropped.

Best regards,
Krzysztof

Re: [PATCH 1/5] dt-bindings: phy: Add STM32MP25 COMBOPHY bindings

[Christian Bruel]

On 8/27/24 15:23, Krzysztof Kozlowski wrote:
> On 27/08/2024 14:24, Christian Bruel wrote:
>> Document the bindings for STM32 COMBOPHY interface, used to support
>> the PCIe and USB3 stm32mp25 drivers.
>> Following entries can be used to tune caracterisation parameters
>>   - st,output-micro-ohms and st,output-vswing-microvolt bindings entries
>> to tune the impedance and voltage swing using discrete simulation results
>>   - st,rx-equalizer register to set the internal rx equalizer filter value.
>>
>> Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
>> Signed-off-by: Christian Bruel <christian.bruel@foss.st.com>
> v1? Or v3?


sorry, forgot to update Subject: it is v3, will resend a v4 with your 
further comments

Regards

Christian

>
>> ---
>>   .../bindings/phy/st,stm32-combophy.yaml       | 144 ++++++++++++++++++
>>   1 file changed, 144 insertions(+)
>>   create mode 100644 Documentation/devicetree/bindings/phy/st,stm32-combophy.yaml
>>
>> diff --git a/Documentation/devicetree/bindings/phy/st,stm32-combophy.yaml b/Documentation/devicetree/bindings/phy/st,stm32-combophy.yaml
>> new file mode 100644
>> index 000000000000..c33a843b83a3
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/phy/st,stm32-combophy.yaml
> Filename matching compatible.

ok

>
>> @@ -0,0 +1,144 @@
>> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/phy/st,stm32-combophy.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: STMicroelectronics STM32MP25 USB3/PCIe COMBOPHY
>> +
>> +maintainers:
>> +  - Christian Bruel <christian.bruel@foss.st.com>
>> +
>> +description:
>> +  Single lane PHY shared (exclusive) between the USB3 and PCIe controllers.
>> +  Supports 5Gbit/s for USB3 and PCIe gen2 or 2.5Gbit/s for PCIe gen1.
>> +
>> +properties:
>> +  compatible:
>> +    const: st,stm32mp25-combophy
>> +
>> +  reg:
>> +    maxItems: 1
>> +
>> +  "#phy-cells":
>> +    const: 1
>> +    description: |
>> +      The cells contain the following arguments.
>> +
>> +      - description: The PHY type
> That's some sort of mess. Is it schema within description or schema? Why
> two descriptions?

yes, indeed

>> +          enum:
>> +            - PHY_TYPE_USB3
>> +            - PHY_TYPE_PCIE
>> +
> ...
>
>> +required:
>> +  - compatible
>> +  - reg
>> +  - st,syscfg
>> +  - '#phy-cells'
>> +  - resets
>> +  - reset-names
>> +  - clocks
>> +  - clock-names
>> +
>> +allOf:
>> +  - if:
>> +      required:
>> +        - wakeup-source
>> +    then:
>> +      anyOf:
>> +        - required: [interrupts]
>> +        - required: [interrupts-extended]
>> +
> I do not see any improvements.
>
> The tag you received was CONDITIONAL. If you do not apply the comments,
> you cannot just apply the tag.

my mistake again.


> Best regards,
> Krzysztof
>