ahci_xgene: Skip the PHY and clock initialization if already configured by the firmware.
authorSuman Tripathi <stripathi@apm.com>
Thu, 28 Aug 2014 09:21:21 +0000 (14:51 +0530)
committerTejun Heo <tj@kernel.org>
Sat, 6 Sep 2014 02:27:14 +0000 (11:27 +0900)
This patch implements the feature to skip the PHY and clock
initialization if it is already configured by the firmware.

Signed-off-by: Loc Ho <lho@apm.com>
Signed-off-by: Suman Tripathi <stripathi@apm.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
drivers/ata/ahci_xgene.c

index c6962300b93c7c6292ed91d62611db6678af1f49..37501fd0973d9fab2ecd3784c3b2a700fd319aa2 100644 (file)
@@ -145,6 +145,14 @@ static unsigned int xgene_ahci_qc_issue(struct ata_queued_cmd *qc)
        return rc;
 }
 
+static bool xgene_ahci_is_memram_inited(struct xgene_ahci_context *ctx)
+{
+       void __iomem *diagcsr = ctx->csr_diag;
+
+       return (readl(diagcsr + CFG_MEM_RAM_SHUTDOWN) == 0 &&
+               readl(diagcsr + BLOCK_MEM_RDY) == 0xFFFFFFFF);
+}
+
 /**
  * xgene_ahci_read_id - Read ID data from the specified device
  * @dev: device
@@ -467,6 +475,11 @@ static int xgene_ahci_probe(struct platform_device *pdev)
                return -ENODEV;
        }
 
+       if (xgene_ahci_is_memram_inited(ctx)) {
+               dev_info(dev, "skip clock and PHY initialization\n");
+               goto skip_clk_phy;
+       }
+
        /* Due to errata, HW requires full toggle transition */
        rc = ahci_platform_enable_clks(hpriv);
        if (rc)
@@ -479,7 +492,7 @@ static int xgene_ahci_probe(struct platform_device *pdev)
 
        /* Configure the host controller */
        xgene_ahci_hw_init(hpriv);
-
+skip_clk_phy:
        hpriv->flags = AHCI_HFLAG_NO_PMP | AHCI_HFLAG_NO_NCQ;
 
        rc = ahci_platform_init_host(pdev, hpriv, &xgene_ahci_port_info);