[PATCH 3/3] mmc: sdhci-of-esdhc: add workaround for T4240 incorrect HOSTVER value

[Yangbo Lu]

For T4240-R1.0-R2.0, the HOSTVER register has incorrcet vender
version value and sdhc spec version value. This will break down
the ADMA data transfer. So add workaround to get right value
VVN=0x13, SVN = 0x1.

Signed-off-by: Yangbo Lu <yangbo...@freescale.com>
---
 drivers/mmc/host/sdhci-esdhc.h    |  5 +++++
 drivers/mmc/host/sdhci-of-esdhc.c | 18 ++++++++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/drivers/mmc/host/sdhci-esdhc.h b/drivers/mmc/host/sdhci-esdhc.h
index 3497cfa..5174233 100644
--- a/drivers/mmc/host/sdhci-esdhc.h
+++ b/drivers/mmc/host/sdhci-esdhc.h
@@ -47,4 +47,9 @@
 
 #define ESDHC_HOST_CONTROL_RES 0x05
 
+unsigned int esdhc_errata;
+
+/* Incorrect host version in T4240 HOSTVER register */
+#define ESDHC_ERRATA_T4240_ERROR_HOSTVER               (1<<0)
+
 #endif /* _DRIVERS_MMC_SDHCI_ESDHC_H */
diff --git a/drivers/mmc/host/sdhci-of-esdhc.c 
b/drivers/mmc/host/sdhci-of-esdhc.c
index 1295a96..c0ad765 100644
--- a/drivers/mmc/host/sdhci-of-esdhc.c
+++ b/drivers/mmc/host/sdhci-of-esdhc.c
@@ -59,6 +59,11 @@ static u16 esdhc_readw(struct sdhci_host *host, int reg)
                ret = in_be32(host->ioaddr + base) & 0xffff;
        else
                ret = (in_be32(host->ioaddr + base) >> shift) & 0xffff;
+
+       if ((reg == SDHCI_HOST_VERSION) &&
+                       (esdhc_errata & ESDHC_ERRATA_T4240_ERROR_HOSTVER))
+               ret = (VENDOR_V_23 << SDHCI_VENDOR_VER_SHIFT) | SDHCI_SPEC_200;
+
        return ret;
 }
 
@@ -352,6 +357,9 @@ static void esdhc_get_property(struct platform_device *pdev)
 {
        struct device_node *np = pdev->dev.of_node;
        struct sdhci_host *host = platform_get_drvdata(pdev);
+       struct device_node *cpus;
+       const u32 *prop;
+       u8 rev = 0xff;
 
        sdhci_get_of_property(pdev);
 
@@ -359,6 +367,11 @@ static void esdhc_get_property(struct platform_device 
*pdev)
        mmc_of_parse(host->mmc);
        mmc_of_parse_voltage(np, &host->ocr_mask);
 
+       cpus = of_find_node_by_path("/cpus");
+       prop = of_get_property(cpus, "cpu-rev", NULL);
+       if (prop)
+               rev = *(u8 *)prop;
+
        if (of_device_is_compatible(np, "fsl,p5040-esdhc") ||
            of_device_is_compatible(np, "fsl,p5020-esdhc") ||
            of_device_is_compatible(np, "fsl,p4080-esdhc") ||
@@ -373,6 +386,11 @@ static void esdhc_get_property(struct platform_device 
*pdev)
                 */
                host->quirks2 |= SDHCI_QUIRK2_BROKEN_HOST_CONTROL;
        }
+
+       esdhc_errata = 0;
+
+       if (of_device_is_compatible(np, "fsl,t4240-esdhc") && rev <= 0x20)
+               esdhc_errata |= ESDHC_ERRATA_T4240_ERROR_HOSTVER;
 }
 
 static int sdhci_esdhc_probe(struct platform_device *pdev)
-- 
2.1.0.27.g96db324

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