Merge branches 'pm-sleep' and 'pm-cpufreq'

[karo-tx-linux.git] / drivers / ata / ahci_xgene.c

diff --git a/drivers/ata/ahci_xgene.c b/drivers/ata/ahci_xgene.c
index 042a9bb45c86d40f4d06511b673ddfc83bea55e2..ee3a3659bd9ef2e173e6e1ac468d5bd88631ee9c 100644 (file)
--- a/drivers/ata/ahci_xgene.c
+++ b/drivers/ata/ahci_xgene.c
@@ -78,6 +78,7 @@
 struct xgene_ahci_context {
        struct ahci_host_priv *hpriv;
        struct device *dev;
+       u8 last_cmd[MAX_AHCI_CHN_PERCTR]; /* tracking the last command issued*/
        void __iomem *csr_core;         /* Core CSR address of IP */
        void __iomem *csr_diag;         /* Diag CSR address of IP */
        void __iomem *csr_axi;          /* AXI CSR address of IP */
@@ -97,6 +98,50 @@ static int xgene_ahci_init_memram(struct xgene_ahci_context *ctx)
        return 0;
 }
 
+/**
+ * xgene_ahci_restart_engine - Restart the dma engine.
+ * @ap : ATA port of interest
+ *
+ * Restarts the dma engine inside the controller.
+ */
+static int xgene_ahci_restart_engine(struct ata_port *ap)
+{
+       struct ahci_host_priv *hpriv = ap->host->private_data;
+
+       ahci_stop_engine(ap);
+       ahci_start_fis_rx(ap);
+       hpriv->start_engine(ap);
+
+       return 0;
+}
+
+/**
+ * xgene_ahci_qc_issue - Issue commands to the device
+ * @qc: Command to issue
+ *
+ * Due to Hardware errata for IDENTIFY DEVICE command, the controller cannot
+ * clear the BSY bit after receiving the PIO setup FIS. This results in the dma
+ * state machine goes into the CMFatalErrorUpdate state and locks up. By
+ * restarting the dma engine, it removes the controller out of lock up state.
+ */
+static unsigned int xgene_ahci_qc_issue(struct ata_queued_cmd *qc)
+{
+       struct ata_port *ap = qc->ap;
+       struct ahci_host_priv *hpriv = ap->host->private_data;
+       struct xgene_ahci_context *ctx = hpriv->plat_data;
+       int rc = 0;
+
+       if (unlikely(ctx->last_cmd[ap->port_no] == ATA_CMD_ID_ATA))
+               xgene_ahci_restart_engine(ap);
+
+       rc = ahci_qc_issue(qc);
+
+       /* Save the last command issued */
+       ctx->last_cmd[ap->port_no] = qc->tf.command;
+
+       return rc;
+}
+
 /**
  * xgene_ahci_read_id - Read ID data from the specified device
  * @dev: device
@@ -104,14 +149,12 @@ static int xgene_ahci_init_memram(struct xgene_ahci_context *ctx)
  * @id: data buffer
  *
  * This custom read ID function is required due to the fact that the HW
- * does not support DEVSLP and the controller state machine may get stuck
- * after processing the ID query command.
+ * does not support DEVSLP.
  */
 static unsigned int xgene_ahci_read_id(struct ata_device *dev,
                                       struct ata_taskfile *tf, u16 *id)
 {
        u32 err_mask;
-       void __iomem *port_mmio = ahci_port_base(dev->link->ap);
 
        err_mask = ata_do_dev_read_id(dev, tf, id);
        if (err_mask)
@@ -133,16 +176,6 @@ static unsigned int xgene_ahci_read_id(struct ata_device *dev,
         */
        id[ATA_ID_FEATURE_SUPP] &= ~(1 << 8);
 
-       /*
-        * Due to HW errata, restart the port if no other command active.
-        * Otherwise the controller may get stuck.
-        */
-       if (!readl(port_mmio + PORT_CMD_ISSUE)) {
-               writel(PORT_CMD_FIS_RX, port_mmio + PORT_CMD);
-               readl(port_mmio + PORT_CMD);    /* Force a barrier */
-               writel(PORT_CMD_FIS_RX | PORT_CMD_START, port_mmio + PORT_CMD);
-               readl(port_mmio + PORT_CMD);    /* Force a barrier */
-       }
        return 0;
 }
 
@@ -300,6 +333,7 @@ static struct ata_port_operations xgene_ahci_ops = {
        .host_stop = xgene_ahci_host_stop,
        .hardreset = xgene_ahci_hardreset,
        .read_id = xgene_ahci_read_id,
+       .qc_issue = xgene_ahci_qc_issue,
 };
 
 static const struct ata_port_info xgene_ahci_port_info = {