Merge branch 'microchip_t1s-update-on-microchip-10base-t1s-phy-driver'

Parthiban Veerasooran says:

====================
microchip_t1s: Update on Microchip 10BASE-T1S PHY driver

This patch series contain the below updates,
- Fixes on the Microchip LAN8670/1/2 10BASE-T1S PHYs support in the
  net/phy/microchip_t1s.c driver.
- Adds support for the Microchip LAN8650/1 Rev.B0 10BASE-T1S Internal
  PHYs in the net/phy/microchip_t1s.c driver.
====================

Link: https://lore.kernel.org/r/20230526152348.70781-1-Parthiban.Veerasooran@microchip.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

Author: Paolo Abeni

drivers/net/phy/Kconfig

@@ -243,9 +243,10 @@ config MICREL_PHY
 	  Supports the KSZ9021, VSC8201, KS8001 PHYs.
 
 config MICROCHIP_T1S_PHY
-	tristate "Microchip 10BASE-T1S Ethernet PHY"
+	tristate "Microchip 10BASE-T1S Ethernet PHYs"
 	help
-	  Currently supports the LAN8670, LAN8671, LAN8672
+	  Currently supports the LAN8670/1/2 Rev.B1 and LAN8650/1 Rev.B0 Internal
+	  PHYs.
 
 config MICROCHIP_PHY
 	tristate "Microchip PHYs"

drivers/net/phy/microchip_t1s.c

@@ -1,19 +1,29 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
- * Driver for Microchip 10BASE-T1S LAN867X PHY
+ * Driver for Microchip 10BASE-T1S PHYs
  *
  * Support: Microchip Phys:
- *  lan8670, lan8671, lan8672
+ *  lan8670/1/2 Rev.B1
+ *  lan8650/1 Rev.B0 Internal PHYs
  */
 
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/phy.h>
 
-#define PHY_ID_LAN867X 0x0007C160
+#define PHY_ID_LAN867X_REVB1 0x0007C162
+#define PHY_ID_LAN865X_REVB0 0x0007C1B3
 
-#define LAN867X_REG_IRQ_1_CTL 0x001C
-#define LAN867X_REG_IRQ_2_CTL 0x001D
+#define LAN867X_REG_STS2 0x0019
+
+#define LAN867x_RESET_COMPLETE_STS BIT(11)
+
+#define LAN865X_REG_CFGPARAM_ADDR 0x00D8
+#define LAN865X_REG_CFGPARAM_DATA 0x00D9
+#define LAN865X_REG_CFGPARAM_CTRL 0x00DA
+#define LAN865X_REG_STS2 0x0019
+
+#define LAN865X_CFGPARAM_READ_ENABLE BIT(1)
 
 /* The arrays below are pulled from the following table from AN1699
  * Access MMD Address Value Mask
@@ -31,72 +41,219 @@
  * W   0x1F 0x0099 0x7F80 ------
  */
 
-static const int lan867x_fixup_registers[12] = {
+static const u32 lan867x_revb1_fixup_registers[12] = {
 	0x00D0, 0x00D1, 0x0084, 0x0085,
 	0x008A, 0x0087, 0x0088, 0x008B,
 	0x0080, 0x00F1, 0x0096, 0x0099,
 };
 
-static const int lan867x_fixup_values[12] = {
+static const u16 lan867x_revb1_fixup_values[12] = {
 	0x0002, 0x0000, 0x3380, 0x0006,
 	0xC000, 0x801C, 0x033F, 0x0404,
 	0x0600, 0x2400, 0x2000, 0x7F80,
 };
 
-static const int lan867x_fixup_masks[12] = {
+static const u16 lan867x_revb1_fixup_masks[12] = {
 	0x0E03, 0x0300, 0xFFC0, 0x000F,
 	0xF800, 0x801C, 0x1FFF, 0xFFFF,
 	0x0600, 0x7F00, 0x2000, 0xFFFF,
 };
 
-static int lan867x_config_init(struct phy_device *phydev)
+/* LAN865x Rev.B0 configuration parameters from AN1760 */
+static const u32 lan865x_revb0_fixup_registers[28] = {
+	0x0091, 0x0081, 0x0043, 0x0044,
+	0x0045, 0x0053, 0x0054, 0x0055,
+	0x0040, 0x0050, 0x00D0, 0x00E9,
+	0x00F5, 0x00F4, 0x00F8, 0x00F9,
+	0x00B0, 0x00B1, 0x00B2, 0x00B3,
+	0x00B4, 0x00B5, 0x00B6, 0x00B7,
+	0x00B8, 0x00B9, 0x00BA, 0x00BB,
+};
+
+static const u16 lan865x_revb0_fixup_values[28] = {
+	0x9660, 0x00C0, 0x00FF, 0xFFFF,
+	0x0000, 0x00FF, 0xFFFF, 0x0000,
+	0x0002, 0x0002, 0x5F21, 0x9E50,
+	0x1CF8, 0xC020, 0x9B00, 0x4E53,
+	0x0103, 0x0910, 0x1D26, 0x002A,
+	0x0103, 0x070D, 0x1720, 0x0027,
+	0x0509, 0x0E13, 0x1C25, 0x002B,
+};
+
+static const u16 lan865x_revb0_fixup_cfg_regs[5] = {
+	0x0084, 0x008A, 0x00AD, 0x00AE, 0x00AF
+};
+
+/* Pulled from AN1760 describing 'indirect read'
+ *
+ * write_register(0x4, 0x00D8, addr)
+ * write_register(0x4, 0x00DA, 0x2)
+ * return (int8)(read_register(0x4, 0x00D9))
+ *
+ * 0x4 refers to memory map selector 4, which maps to MDIO_MMD_VEND2
+ */
+static int lan865x_revb0_indirect_read(struct phy_device *phydev, u16 addr)
+{
+	int ret;
+
+	ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, LAN865X_REG_CFGPARAM_ADDR,
+			    addr);
+	if (ret)
+		return ret;
+
+	ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, LAN865X_REG_CFGPARAM_CTRL,
+			    LAN865X_CFGPARAM_READ_ENABLE);
+	if (ret)
+		return ret;
+
+	return phy_read_mmd(phydev, MDIO_MMD_VEND2, LAN865X_REG_CFGPARAM_DATA);
+}
+
+/* This is pulled straight from AN1760 from 'calculation of offset 1' &
+ * 'calculation of offset 2'
+ */
+static int lan865x_generate_cfg_offsets(struct phy_device *phydev, s8 offsets[2])
+{
+	const u16 fixup_regs[2] = {0x0004, 0x0008};
+	int ret;
+
+	for (int i = 0; i < ARRAY_SIZE(fixup_regs); i++) {
+		ret = lan865x_revb0_indirect_read(phydev, fixup_regs[i]);
+		if (ret < 0)
+			return ret;
+		if (ret & BIT(4))
+			offsets[i] = ret | 0xE0;
+		else
+			offsets[i] = ret;
+	}
+
+	return 0;
+}
+
+static int lan865x_read_cfg_params(struct phy_device *phydev, u16 cfg_params[])
+{
+	int ret;
+
+	for (int i = 0; i < ARRAY_SIZE(lan865x_revb0_fixup_cfg_regs); i++) {
+		ret = phy_read_mmd(phydev, MDIO_MMD_VEND2,
+				   lan865x_revb0_fixup_cfg_regs[i]);
+		if (ret < 0)
+			return ret;
+		cfg_params[i] = (u16)ret;
+	}
+
+	return 0;
+}
+
+static int lan865x_write_cfg_params(struct phy_device *phydev, u16 cfg_params[])
 {
-	/* HW quirk: Microchip states in the application note (AN1699) for the phy
-	 * that a set of read-modify-write (rmw) operations has to be performed
-	 * on a set of seemingly magic registers.
-	 * The result of these operations is just described as 'optimal performance'
-	 * Microchip gives no explanation as to what these mmd regs do,
-	 * in fact they are marked as reserved in the datasheet.
-	 * It is unclear if phy_modify_mmd would be safe to use or if a write
-	 * really has to happen to each register.
-	 * In order to exactly conform to what is stated in the AN phy_write_mmd is
-	 * used, which might then write the same value back as read + modified.
+	int ret;
+
+	for (int i = 0; i < ARRAY_SIZE(lan865x_revb0_fixup_cfg_regs); i++) {
+		ret = phy_write_mmd(phydev, MDIO_MMD_VEND2,
+				    lan865x_revb0_fixup_cfg_regs[i],
+				    cfg_params[i]);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int lan865x_setup_cfgparam(struct phy_device *phydev)
+{
+	u16 cfg_params[ARRAY_SIZE(lan865x_revb0_fixup_cfg_regs)];
+	u16 cfg_results[5];
+	s8 offsets[2];
+	int ret;
+
+	ret = lan865x_generate_cfg_offsets(phydev, offsets);
+	if (ret)
+		return ret;
+
+	ret = lan865x_read_cfg_params(phydev, cfg_params);
+	if (ret)
+		return ret;
+
+	cfg_results[0] = (cfg_params[0] & 0x000F) |
+			  FIELD_PREP(GENMASK(15, 10), 9 + offsets[0]) |
+			  FIELD_PREP(GENMASK(15, 4), 14 + offsets[0]);
+	cfg_results[1] = (cfg_params[1] & 0x03FF) |
+			  FIELD_PREP(GENMASK(15, 10), 40 + offsets[1]);
+	cfg_results[2] = (cfg_params[2] & 0xC0C0) |
+			  FIELD_PREP(GENMASK(15, 8), 5 + offsets[0]) |
+			  (9 + offsets[0]);
+	cfg_results[3] = (cfg_params[3] & 0xC0C0) |
+			  FIELD_PREP(GENMASK(15, 8), 9 + offsets[0]) |
+			  (14 + offsets[0]);
+	cfg_results[4] = (cfg_params[4] & 0xC0C0) |
+			  FIELD_PREP(GENMASK(15, 8), 17 + offsets[0]) |
+			  (22 + offsets[0]);
+
+	return lan865x_write_cfg_params(phydev, cfg_results);
+}
+
+static int lan865x_revb0_config_init(struct phy_device *phydev)
+{
+	int ret;
+
+	/* Reference to AN1760
+	 * https://ww1.microchip.com/downloads/aemDocuments/documents/AIS/ProductDocuments/SupportingCollateral/AN-LAN8650-1-Configuration-60001760.pdf
+	 */
+	for (int i = 0; i < ARRAY_SIZE(lan865x_revb0_fixup_registers); i++) {
+		ret = phy_write_mmd(phydev, MDIO_MMD_VEND2,
+				    lan865x_revb0_fixup_registers[i],
+				    lan865x_revb0_fixup_values[i]);
+		if (ret)
+			return ret;
+	}
+	/* Function to calculate and write the configuration parameters in the
+	 * 0x0084, 0x008A, 0x00AD, 0x00AE and 0x00AF registers (from AN1760)
 	 */
+	return lan865x_setup_cfgparam(phydev);
+}
 
-	int reg_value;
+static int lan867x_revb1_config_init(struct phy_device *phydev)
+{
 	int err;
-	int reg;
 
-	/* Read-Modified Write Pseudocode (from AN1699)
-	 * current_val = read_register(mmd, addr) // Read current register value
-	 * new_val = current_val AND (NOT mask) // Clear bit fields to be written
-	 * new_val = new_val OR value // Set bits
-	 * write_register(mmd, addr, new_val) // Write back updated register value
+	/* The chip completes a reset in 3us, we might get here earlier than
+	 * that, as an added margin we'll conditionally sleep 5us.
 	 */
-	for (int i = 0; i < ARRAY_SIZE(lan867x_fixup_registers); i++) {
-		reg = lan867x_fixup_registers[i];
-		reg_value = phy_read_mmd(phydev, MDIO_MMD_VEND2, reg);
-		reg_value &= ~lan867x_fixup_masks[i];
-		reg_value |= lan867x_fixup_values[i];
-		err = phy_write_mmd(phydev, MDIO_MMD_VEND2, reg, reg_value);
-		if (err != 0)
+	err = phy_read_mmd(phydev, MDIO_MMD_VEND2, LAN867X_REG_STS2);
+	if (err < 0)
+		return err;
+
+	if (!(err & LAN867x_RESET_COMPLETE_STS)) {
+		udelay(5);
+		err = phy_read_mmd(phydev, MDIO_MMD_VEND2, LAN867X_REG_STS2);
+		if (err < 0)
 			return err;
+		if (!(err & LAN867x_RESET_COMPLETE_STS)) {
+			phydev_err(phydev, "PHY reset failed\n");
+			return -ENODEV;
+		}
 	}
 
-	/* None of the interrupts in the lan867x phy seem relevant.
-	 * Other phys inspect the link status and call phy_trigger_machine
-	 * in the interrupt handler.
-	 * This phy does not support link status, and thus has no interrupt
-	 * for it either.
-	 * So we'll just disable all interrupts on the chip.
+	/* Reference to AN1699
+	 * https://ww1.microchip.com/downloads/aemDocuments/documents/AIS/ProductDocuments/SupportingCollateral/AN-LAN8670-1-2-config-60001699.pdf
+	 * AN1699 says Read, Modify, Write, but the Write is not required if the
+	 * register already has the required value. So it is safe to use
+	 * phy_modify_mmd here.
 	 */
-	err = phy_write_mmd(phydev, MDIO_MMD_VEND2, LAN867X_REG_IRQ_1_CTL, 0xFFFF);
-	if (err != 0)
-		return err;
-	return phy_write_mmd(phydev, MDIO_MMD_VEND2, LAN867X_REG_IRQ_2_CTL, 0xFFFF);
+	for (int i = 0; i < ARRAY_SIZE(lan867x_revb1_fixup_registers); i++) {
+		err = phy_modify_mmd(phydev, MDIO_MMD_VEND2,
+				     lan867x_revb1_fixup_registers[i],
+				     lan867x_revb1_fixup_masks[i],
+				     lan867x_revb1_fixup_values[i]);
+		if (err)
+			return err;
+	}
+
+	return 0;
 }
 
-static int lan867x_read_status(struct phy_device *phydev)
+static int lan86xx_read_status(struct phy_device *phydev)
 {
 	/* The phy has some limitations, namely:
 	 *  - always reports link up
@@ -111,28 +268,39 @@ static int lan867x_read_status(struct phy_device *phydev)
 	return 0;
 }
 
-static struct phy_driver lan867x_driver[] = {
+static struct phy_driver microchip_t1s_driver[] = {
 	{
-		PHY_ID_MATCH_MODEL(PHY_ID_LAN867X),
-		.name               = "LAN867X",
+		PHY_ID_MATCH_EXACT(PHY_ID_LAN867X_REVB1),
+		.name               = "LAN867X Rev.B1",
 		.features           = PHY_BASIC_T1S_P2MP_FEATURES,
-		.config_init        = lan867x_config_init,
-		.read_status        = lan867x_read_status,
+		.config_init        = lan867x_revb1_config_init,
+		.read_status        = lan86xx_read_status,
 		.get_plca_cfg	    = genphy_c45_plca_get_cfg,
 		.set_plca_cfg	    = genphy_c45_plca_set_cfg,
 		.get_plca_status    = genphy_c45_plca_get_status,
-	}
+	},
+	{
+		PHY_ID_MATCH_EXACT(PHY_ID_LAN865X_REVB0),
+		.name               = "LAN865X Rev.B0 Internal Phy",
+		.features           = PHY_BASIC_T1S_P2MP_FEATURES,
+		.config_init        = lan865x_revb0_config_init,
+		.read_status        = lan86xx_read_status,
+		.get_plca_cfg	    = genphy_c45_plca_get_cfg,
+		.set_plca_cfg	    = genphy_c45_plca_set_cfg,
+		.get_plca_status    = genphy_c45_plca_get_status,
+	},
 };
 
-module_phy_driver(lan867x_driver);
+module_phy_driver(microchip_t1s_driver);
 
 static struct mdio_device_id __maybe_unused tbl[] = {
-	{ PHY_ID_MATCH_MODEL(PHY_ID_LAN867X) },
+	{ PHY_ID_MATCH_EXACT(PHY_ID_LAN867X_REVB1) },
+	{ PHY_ID_MATCH_EXACT(PHY_ID_LAN865X_REVB0) },
 	{ }
 };
 
 MODULE_DEVICE_TABLE(mdio, tbl);
 
-MODULE_DESCRIPTION("Microchip 10BASE-T1S lan867x Phy driver");
+MODULE_DESCRIPTION("Microchip 10BASE-T1S PHYs driver");
 MODULE_AUTHOR("Ramón Nordin Rodriguez");
 MODULE_LICENSE("GPL");