Merge branch 'net-phy-mscc-support-vsc8501'

David Epping says:

====================
net: phy: mscc: support VSC8501

this updated series of patches adds support for the VSC8501 Ethernet
PHY and fixes support for the VSC8502 PHY in cases where no other
software (like U-Boot) has initialized the PHY after power up.

The first patch simply adds the VSC8502 to the MODULE_DEVICE_TABLE,
where I guess it was unintentionally missing. I have no hardware to
test my change.

The second patch adds the VSC8501 PHY with exactly the same driver
implementation as the existing VSC8502.

The (new) third patch removes phydev locking from
vsc85xx_rgmii_set_skews(), as discussed for v2 of the patch set.

The (now) fourth patch fixes the initialization for VSC8501 and VSC8502.
I have tested this patch with VSC8501 on hardware in RGMII mode only.
https://ww1.microchip.com/downloads/aemDocuments/documents/UNG/ProductDocuments/DataSheets/VSC8501-03_Datasheet_60001741A.PDF
https://ww1.microchip.com/downloads/aemDocuments/documents/UNG/ProductDocuments/DataSheets/VSC8502-03_Datasheet_60001742B.pdf
Table 4-42 "RGMII CONTROL, ADDRESS 20E2 (0X14)" Bit 11 for each of
them.
By default the RX_CLK is disabled for these PHYs. In cases where no
other software, like U-Boot, enabled the clock, this results in no
received packets being handed to the MAC.
The patch enables this clock output.
According to Microchip support (case number 01268776) this applies
to all modes (RGMII, GMII, and MII).

Other PHYs sharing the same register map and code, like
VSC8530/31/40/41 have the clock enabled and the relevant bit 11 is
reserved and read-only for them. As per previous discussion the
patch still clears the bit on these PHYs, too, possibly more easily
supporting other future PHYs implementing this functionality.

For the VSC8572 family of PHYs, having a different register map,
no such changes are applied.
====================

Link: https://lore.kernel.org/r/20230523153108.18548-1-david.epping@missinglinkelectronics.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

2 files changed, 55 insertions, 29 deletions

diff --git a/drivers/net/phy/mscc/mscc.h b/drivers/net/phy/mscc/mscc.h
index a50235fdf7d99..defe5cc6d4fce 100644
--- a/drivers/net/phy/mscc/mscc.h
+++ b/drivers/net/phy/mscc/mscc.h
@@ -179,6 +179,7 @@ enum rgmii_clock_delay {
 #define VSC8502_RGMII_CNTL		  20
 #define VSC8502_RGMII_RX_DELAY_MASK	  0x0070
 #define VSC8502_RGMII_TX_DELAY_MASK	  0x0007
+#define VSC8502_RGMII_RX_CLK_DISABLE	  0x0800
 
 #define MSCC_PHY_WOL_LOWER_MAC_ADDR	  21
 #define MSCC_PHY_WOL_MID_MAC_ADDR	  22
@@ -276,6 +277,7 @@ enum rgmii_clock_delay {
 /* Microsemi PHY ID's
  *   Code assumes lowest nibble is 0
  */
+#define PHY_ID_VSC8501			  0x00070530
 #define PHY_ID_VSC8502			  0x00070630
 #define PHY_ID_VSC8504			  0x000704c0
 #define PHY_ID_VSC8514			  0x00070670
diff --git a/drivers/net/phy/mscc/mscc_main.c b/drivers/net/phy/mscc/mscc_main.c
index 62bf99e45af16..28df8a2e4230f 100644
--- a/drivers/net/phy/mscc/mscc_main.c
+++ b/drivers/net/phy/mscc/mscc_main.c
@@ -519,16 +519,27 @@ out_unlock:
  *  * 2.0 ns (which causes the data to be sampled at exactly half way between
  *    clock transitions at 1000 Mbps) if delays should be enabled
  */
-static int vsc85xx_rgmii_set_skews(struct phy_device *phydev, u32 rgmii_cntl,
-				   u16 rgmii_rx_delay_mask,
-				   u16 rgmii_tx_delay_mask)
+static int vsc85xx_update_rgmii_cntl(struct phy_device *phydev, u32 rgmii_cntl,
+				     u16 rgmii_rx_delay_mask,
+				     u16 rgmii_tx_delay_mask)
 {
 	u16 rgmii_rx_delay_pos = ffs(rgmii_rx_delay_mask) - 1;
 	u16 rgmii_tx_delay_pos = ffs(rgmii_tx_delay_mask) - 1;
 	u16 reg_val = 0;
-	int rc;
+	u16 mask = 0;
+	int rc = 0;
 
-	mutex_lock(&phydev->lock);
+	/* For traffic to pass, the VSC8502 family needs the RX_CLK disable bit
+	 * to be unset for all PHY modes, so do that as part of the paged
+	 * register modification.
+	 * For some family members (like VSC8530/31/40/41) this bit is reserved
+	 * and read-only, and the RX clock is enabled by default.
+	 */
+	if (rgmii_cntl == VSC8502_RGMII_CNTL)
+		mask |= VSC8502_RGMII_RX_CLK_DISABLE;
+
+	if (phy_interface_is_rgmii(phydev))
+		mask |= rgmii_rx_delay_mask | rgmii_tx_delay_mask;
 
 	if (phydev->interface == PHY_INTERFACE_MODE_RGMII_RXID ||
 	    phydev->interface == PHY_INTERFACE_MODE_RGMII_ID)
@@ -537,31 +548,20 @@ static int vsc85xx_rgmii_set_skews(struct phy_device *phydev, u32 rgmii_cntl,
 	    phydev->interface == PHY_INTERFACE_MODE_RGMII_ID)
 		reg_val |= RGMII_CLK_DELAY_2_0_NS << rgmii_tx_delay_pos;
 
-	rc = phy_modify_paged(phydev, MSCC_PHY_PAGE_EXTENDED_2,
-			      rgmii_cntl,
-			      rgmii_rx_delay_mask | rgmii_tx_delay_mask,
-			      reg_val);
-
-	mutex_unlock(&phydev->lock);
+	if (mask)
+		rc = phy_modify_paged(phydev, MSCC_PHY_PAGE_EXTENDED_2,
+				      rgmii_cntl, mask, reg_val);
 
 	return rc;
 }
 
 static int vsc85xx_default_config(struct phy_device *phydev)
 {
-	int rc;
-
 	phydev->mdix_ctrl = ETH_TP_MDI_AUTO;
 
-	if (phy_interface_mode_is_rgmii(phydev->interface)) {
-		rc = vsc85xx_rgmii_set_skews(phydev, VSC8502_RGMII_CNTL,
-					     VSC8502_RGMII_RX_DELAY_MASK,
-					     VSC8502_RGMII_TX_DELAY_MASK);
-		if (rc)
-			return rc;
-	}
-
-	return 0;
+	return vsc85xx_update_rgmii_cntl(phydev, VSC8502_RGMII_CNTL,
+					 VSC8502_RGMII_RX_DELAY_MASK,
+					 VSC8502_RGMII_TX_DELAY_MASK);
 }
 
 static int vsc85xx_get_tunable(struct phy_device *phydev,
@@ -1758,13 +1758,11 @@ static int vsc8584_config_init(struct phy_device *phydev)
 	if (ret)
 		return ret;
 
-	if (phy_interface_is_rgmii(phydev)) {
-		ret = vsc85xx_rgmii_set_skews(phydev, VSC8572_RGMII_CNTL,
-					      VSC8572_RGMII_RX_DELAY_MASK,
-					      VSC8572_RGMII_TX_DELAY_MASK);
-		if (ret)
-			return ret;
-	}
+	ret = vsc85xx_update_rgmii_cntl(phydev, VSC8572_RGMII_CNTL,
+					VSC8572_RGMII_RX_DELAY_MASK,
+					VSC8572_RGMII_TX_DELAY_MASK);
+	if (ret)
+		return ret;
 
 	ret = genphy_soft_reset(phydev);
 	if (ret)
@@ -2317,6 +2315,30 @@ static int vsc85xx_probe(struct phy_device *phydev)
 /* Microsemi VSC85xx PHYs */
 static struct phy_driver vsc85xx_driver[] = {
 {
+	.phy_id		= PHY_ID_VSC8501,
+	.name		= "Microsemi GE VSC8501 SyncE",
+	.phy_id_mask	= 0xfffffff0,
+	/* PHY_BASIC_FEATURES */
+	.soft_reset	= &genphy_soft_reset,
+	.config_init	= &vsc85xx_config_init,
+	.config_aneg    = &vsc85xx_config_aneg,
+	.read_status	= &vsc85xx_read_status,
+	.handle_interrupt = vsc85xx_handle_interrupt,
+	.config_intr	= &vsc85xx_config_intr,
+	.suspend	= &genphy_suspend,
+	.resume		= &genphy_resume,
+	.probe		= &vsc85xx_probe,
+	.set_wol	= &vsc85xx_wol_set,
+	.get_wol	= &vsc85xx_wol_get,
+	.get_tunable	= &vsc85xx_get_tunable,
+	.set_tunable	= &vsc85xx_set_tunable,
+	.read_page	= &vsc85xx_phy_read_page,
+	.write_page	= &vsc85xx_phy_write_page,
+	.get_sset_count = &vsc85xx_get_sset_count,
+	.get_strings    = &vsc85xx_get_strings,
+	.get_stats      = &vsc85xx_get_stats,
+},
+{
 	.phy_id		= PHY_ID_VSC8502,
 	.name		= "Microsemi GE VSC8502 SyncE",
 	.phy_id_mask	= 0xfffffff0,
@@ -2656,6 +2678,8 @@ static struct phy_driver vsc85xx_driver[] = {
 module_phy_driver(vsc85xx_driver);
 
 static struct mdio_device_id __maybe_unused vsc85xx_tbl[] = {
+	{ PHY_ID_VSC8501, 0xfffffff0, },
+	{ PHY_ID_VSC8502, 0xfffffff0, },
 	{ PHY_ID_VSC8504, 0xfffffff0, },
 	{ PHY_ID_VSC8514, 0xfffffff0, },
 	{ PHY_ID_VSC8530, 0xfffffff0, },