ata: sata_mv: fix disk hotplug for Armada 370/XP SoCs

On Armada 370/XP SoCs, once a disk is removed from a SATA port, then the
re-plug events are not detected by the sata_mv driver. This patch fixes
the issue by updating the PHY speed in the LP_PHY_CTL register (0x58)
according to the SControl speed.

Note that this fix is only applied if the compatible string
"marvell,armada-370-sata" is found in the SATA DT node.

Fixes: 9ae6f740b49f ("arm: mach-mvebu: add support for Armada 370 and Armada XP with DT")
Signed-off-by: Lior Amsalem <alior@marvell.com>
Signed-off-by: Nadav Haklai <nadavh@marvell.com>
Signed-off-by: Simon Guinot <simon.guinot@sequanux.org>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Gregory Clement <gregory.clement@free-electrons.com>
Cc: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Cc: stable@vger.kernel.org # v3.6+
Acked-by: Jason Cooper <jason@lakedaemon.net>
Signed-off-by: Tejun Heo <tj@kernel.org>

1 files changed, 24 insertions, 0 deletions

diff --git a/drivers/ata/sata_mv.c b/drivers/ata/sata_mv.c
index 4ec5368c10f7..dc9d4b1ea4ec 100644
--- a/drivers/ata/sata_mv.c
+++ b/drivers/ata/sata_mv.c
@@ -304,6 +304,7 @@ enum {
         MV5_LTMODE              = 0x30,
         MV5_PHY_CTL             = 0x0C,
         SATA_IFCFG              = 0x050,
+        LP_PHY_CTL              = 0x058,
 
         MV_M2_PREAMP_MASK       = 0x7e0,
 
@@ -431,6 +432,7 @@ enum {
         MV_HP_CUT_THROUGH       = (1 << 10),    /* can use EDMA cut-through */
         MV_HP_FLAG_SOC          = (1 << 11),    /* SystemOnChip, no PCI */
         MV_HP_QUIRK_LED_BLINK_EN = (1 << 12),   /* is led blinking enabled? */
+        MV_HP_FIX_LP_PHY_CTL    = (1 << 13),    /* fix speed in LP_PHY_CTL ? */
 
         /* Port private flags (pp_flags) */
         MV_PP_FLAG_EDMA_EN      = (1 << 0),     /* is EDMA engine enabled? */
@@ -1358,6 +1360,7 @@ static int mv_scr_write(struct ata_link *link, unsigned int sc_reg_in, u32 val)
 
         if (ofs != 0xffffffffU) {
                 void __iomem *addr = mv_ap_base(link->ap) + ofs;
+                struct mv_host_priv *hpriv = link->ap->host->private_data;
                 if (sc_reg_in == SCR_CONTROL) {
                         /*
                          * Workaround for 88SX60x1 FEr SATA#26:
@@ -1374,6 +1377,18 @@ static int mv_scr_write(struct ata_link *link, unsigned int sc_reg_in, u32 val)
                          */
                         if ((val & 0xf) == 1 || (readl(addr) & 0xf) == 1)
                                 val |= 0xf000;
+
+                        if (hpriv->hp_flags & MV_HP_FIX_LP_PHY_CTL) {
+                                void __iomem *lp_phy_addr =
+                                        mv_ap_base(link->ap) + LP_PHY_CTL;
+                                /*
+                                 * Set PHY speed according to SControl speed.
+                                 */
+                                if ((val & 0xf0) == 0x10)
+                                        writelfl(0x7, lp_phy_addr);
+                                else
+                                        writelfl(0x227, lp_phy_addr);
+                        }
                 }
                 writelfl(val, addr);
                 return 0;
@@ -4110,6 +4125,15 @@ static int mv_platform_probe(struct platform_device *pdev)
         if (rc)
                 goto err;
 
+        /*
+         * To allow disk hotplug on Armada 370/XP SoCs, the PHY speed must be
+         * updated in the LP_PHY_CTL register.
+         */
+        if (pdev->dev.of_node &&
+                of_device_is_compatible(pdev->dev.of_node,
+                                        "marvell,armada-370-sata"))
+                hpriv->hp_flags |= MV_HP_FIX_LP_PHY_CTL;
+
         /* initialize adapter */
         rc = mv_init_host(host);
         if (rc)