Merge branch 'mvneta_qsgmii'

Thomas Petazzoni says:

====================
net: mvneta: fix usage as a module, and support QSGMII properly

This set of patches is a new attempt at fixing the operation of the
mvneta driver when built as a module. For the record, the previous
attempt, merged in commit e3a8786c10
('net: mvneta: fix usage as a module on RGMII configurations') caused
problems for all RGMII configurations.

In fact, it turned out that the MAC to PHY connection on the Armada XP
GP, which was described as using RGMII-ID according to its Device
Tree, is in fact a QSGMII connection. And the RGMII and QSGMII
configurations have to be handled in a different way in the driver,
because the SERDES configuration is different in those two cases.

So, this patch series fixes that by:

 * Adding minimal handling of a "qsgmii" connection type in the PHY
   layer. Mainly to make sure that a "qsgmii" phy-mode in the Device
   Tree is recognized, and handed over to the driver as
   PHY_INTERFACE_QSGMII.

 * Changing the mvneta driver to properly configure the RGMIIEn and
   PCSEn bits in the GMAC_CTRL_2 register, and configure the SERDES
   register, in the three possible cases: RGMII, SGMII and QSGMII.

 * Updating the Device Tree of the Armada XP GP board to reflect the
   fact that it uses a QSGMII MAC/PHY connection.

PATCH 1 and 2 would be merged by David Miller, through the net tree,
while PATCH 3 would be merged by the mach-mvebu maintainers, through
their tree and arm-soc.

This set of patches has been tested on:

 * Armada XP GP (four QSGMII interfaces)
 * Armada XP DB (two RGMII interfaces and two SGMII interfaces)
 * Armada 370 Mirabox (two RGMII interfaces)

I've tested both the driver built-in, and compiled as a module.

Since the last attempt at fixing this was quite a fiasco, I'd like
this new attempt to be tested more widely before being applied. I'll
try to do some testing on other Armada boards I have, but independent
testing from other persons would also be appreciated.

Note that these patches apply after reverting the previous attempt,
obviously.
====================

Tested-by: Arnaud Ebalard <arno@natisbad.org>
Tested-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/devicetree/bindings/net/ethernet.txt

@@ -10,7 +10,7 @@ The following properties are common to the Ethernet controllers:
 - max-frame-size: number, maximum transfer unit (IEEE defined MTU), rather than
   the maximum frame size (there's contradiction in ePAPR).
 - phy-mode: string, operation mode of the PHY interface; supported values are
-  "mii", "gmii", "sgmii", "tbi", "rev-mii", "rmii", "rgmii", "rgmii-id",
+  "mii", "gmii", "sgmii", "qsgmii", "tbi", "rev-mii", "rmii", "rgmii", "rgmii-id",
   "rgmii-rxid", "rgmii-txid", "rtbi", "smii", "xgmii"; this is now a de-facto
   standard property;
 - phy-connection-type: the same as "phy-mode" property but described in ePAPR;

drivers/net/ethernet/marvell/mvneta.c

@@ -89,8 +89,9 @@
 #define      MVNETA_TX_IN_PRGRS                  BIT(1)
 #define      MVNETA_TX_FIFO_EMPTY                BIT(8)
 #define MVNETA_RX_MIN_FRAME_SIZE                 0x247c
-#define MVNETA_SGMII_SERDES_CFG			 0x24A0
+#define MVNETA_SERDES_CFG			 0x24A0
 #define      MVNETA_SGMII_SERDES_PROTO		 0x0cc7
+#define      MVNETA_QSGMII_SERDES_PROTO		 0x0667
 #define MVNETA_TYPE_PRIO                         0x24bc
 #define      MVNETA_FORCE_UNI                    BIT(21)
 #define MVNETA_TXQ_CMD_1                         0x24e4
@@ -711,35 +712,6 @@ static void mvneta_rxq_bm_disable(struct mvneta_port *pp,
 	mvreg_write(pp, MVNETA_RXQ_CONFIG_REG(rxq->id), val);
 }
 
-
-
-/* Sets the RGMII Enable bit (RGMIIEn) in port MAC control register */
-static void mvneta_gmac_rgmii_set(struct mvneta_port *pp, int enable)
-{
-	u32  val;
-
-	val = mvreg_read(pp, MVNETA_GMAC_CTRL_2);
-
-	if (enable)
-		val |= MVNETA_GMAC2_PORT_RGMII;
-	else
-		val &= ~MVNETA_GMAC2_PORT_RGMII;
-
-	mvreg_write(pp, MVNETA_GMAC_CTRL_2, val);
-}
-
-/* Config SGMII port */
-static void mvneta_port_sgmii_config(struct mvneta_port *pp)
-{
-	u32 val;
-
-	val = mvreg_read(pp, MVNETA_GMAC_CTRL_2);
-	val |= MVNETA_GMAC2_PCS_ENABLE;
-	mvreg_write(pp, MVNETA_GMAC_CTRL_2, val);
-
-	mvreg_write(pp, MVNETA_SGMII_SERDES_CFG, MVNETA_SGMII_SERDES_PROTO);
-}
-
 /* Start the Ethernet port RX and TX activity */
 static void mvneta_port_up(struct mvneta_port *pp)
 {
@@ -2749,26 +2721,44 @@ static void mvneta_conf_mbus_windows(struct mvneta_port *pp,
 }
 
 /* Power up the port */
-static void mvneta_port_power_up(struct mvneta_port *pp, int phy_mode)
+static int mvneta_port_power_up(struct mvneta_port *pp, int phy_mode)
 {
-	u32 val;
+	u32 ctrl;
 
 	/* MAC Cause register should be cleared */
 	mvreg_write(pp, MVNETA_UNIT_INTR_CAUSE, 0);
 
-	if (phy_mode == PHY_INTERFACE_MODE_SGMII)
+	ctrl = mvreg_read(pp, MVNETA_GMAC_CTRL_2);
-		mvneta_port_sgmii_config(pp);
 
-	mvneta_gmac_rgmii_set(pp, 1);
+	/* Even though it might look weird, when we're configured in
+	 * SGMII or QSGMII mode, the RGMII bit needs to be set.
+	 */
+	switch(phy_mode) {
+	case PHY_INTERFACE_MODE_QSGMII:
+		mvreg_write(pp, MVNETA_SERDES_CFG, MVNETA_QSGMII_SERDES_PROTO);
+		ctrl |= MVNETA_GMAC2_PCS_ENABLE | MVNETA_GMAC2_PORT_RGMII;
+		break;
+	case PHY_INTERFACE_MODE_SGMII:
+		mvreg_write(pp, MVNETA_SERDES_CFG, MVNETA_SGMII_SERDES_PROTO);
+		ctrl |= MVNETA_GMAC2_PCS_ENABLE | MVNETA_GMAC2_PORT_RGMII;
+		break;
+	case PHY_INTERFACE_MODE_RGMII:
+	case PHY_INTERFACE_MODE_RGMII_ID:
+		ctrl |= MVNETA_GMAC2_PORT_RGMII;
+		break;
+	default:
+		return -EINVAL;
+	}
 
 	/* Cancel Port Reset */
-	val = mvreg_read(pp, MVNETA_GMAC_CTRL_2);
+	ctrl &= ~MVNETA_GMAC2_PORT_RESET;
-	val &= ~MVNETA_GMAC2_PORT_RESET;
+	mvreg_write(pp, MVNETA_GMAC_CTRL_2, ctrl);
-	mvreg_write(pp, MVNETA_GMAC_CTRL_2, val);
 
 	while ((mvreg_read(pp, MVNETA_GMAC_CTRL_2) &
 		MVNETA_GMAC2_PORT_RESET) != 0)
 		continue;
+
+	return 0;
 }
 
 /* Device initialization routine */
@@ -2879,7 +2869,12 @@ static int mvneta_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev, "can't init eth hal\n");
 		goto err_free_stats;
 	}
-	mvneta_port_power_up(pp, phy_mode);
+
+	err = mvneta_port_power_up(pp, phy_mode);
+	if (err < 0) {
+		dev_err(&pdev->dev, "can't power up port\n");
+		goto err_deinit;
+	}
 
 	dram_target_info = mv_mbus_dram_info();
 	if (dram_target_info)

include/linux/phy.h

@@ -75,6 +75,7 @@ typedef enum {
 	PHY_INTERFACE_MODE_SMII,
 	PHY_INTERFACE_MODE_XGMII,
 	PHY_INTERFACE_MODE_MOCA,
+	PHY_INTERFACE_MODE_QSGMII,
 	PHY_INTERFACE_MODE_MAX,
 } phy_interface_t;
 
@@ -116,6 +117,8 @@ static inline const char *phy_modes(phy_interface_t interface)
 		return "xgmii";
 	case PHY_INTERFACE_MODE_MOCA:
 		return "moca";
+	case PHY_INTERFACE_MODE_QSGMII:
+		return "qsgmii";
 	default:
 		return "unknown";
 	}