mmc: tegra: Write xfer_mode, CMD regs in together

If there is a gap between xfer mode and command register writes,
tegra SDMMC controller can sometimes issue a spurious command before
the CMD register is written. To avoid this, these two registers need
to be written together in a single write operation.

This is implemented as an NVQUIRK as it applies to T114, T124 and
T132.

Signed-off-by: Pavan Kunapuli <pkunapuli@nvidia.com>
Signed-off-by: Rhyland Klein <rklein@nvidia.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
This commit is contained in:
Pavan Kunapuli 2015-01-28 11:45:16 -05:00 committed by Ulf Hansson
parent 0501be6429
commit 352ee868dd

View File

@ -41,6 +41,7 @@
#define NVQUIRK_DISABLE_SDR50 BIT(3)
#define NVQUIRK_DISABLE_SDR104 BIT(4)
#define NVQUIRK_DISABLE_DDR50 BIT(5)
#define NVQUIRK_SHADOW_XFER_MODE_REG BIT(6)
struct sdhci_tegra_soc_data {
const struct sdhci_pltfm_data *pdata;
@ -67,6 +68,31 @@ static u16 tegra_sdhci_readw(struct sdhci_host *host, int reg)
return readw(host->ioaddr + reg);
}
static void tegra_sdhci_writew(struct sdhci_host *host, u16 val, int reg)
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct sdhci_tegra *tegra_host = pltfm_host->priv;
const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
if (soc_data->nvquirks & NVQUIRK_SHADOW_XFER_MODE_REG) {
switch (reg) {
case SDHCI_TRANSFER_MODE:
/*
* Postpone this write, we must do it together with a
* command write that is down below.
*/
pltfm_host->xfer_mode_shadow = val;
return;
case SDHCI_COMMAND:
writel((val << 16) | pltfm_host->xfer_mode_shadow,
host->ioaddr + SDHCI_TRANSFER_MODE);
return;
}
}
writew(val, host->ioaddr + reg);
}
static void tegra_sdhci_writel(struct sdhci_host *host, u32 val, int reg)
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
@ -147,6 +173,7 @@ static void tegra_sdhci_set_bus_width(struct sdhci_host *host, int bus_width)
static const struct sdhci_ops tegra_sdhci_ops = {
.get_ro = tegra_sdhci_get_ro,
.read_w = tegra_sdhci_readw,
.write_w = tegra_sdhci_writew,
.write_l = tegra_sdhci_writel,
.set_clock = sdhci_set_clock,
.set_bus_width = tegra_sdhci_set_bus_width,
@ -201,7 +228,8 @@ static struct sdhci_tegra_soc_data soc_data_tegra114 = {
.pdata = &sdhci_tegra114_pdata,
.nvquirks = NVQUIRK_DISABLE_SDR50 |
NVQUIRK_DISABLE_DDR50 |
NVQUIRK_DISABLE_SDR104,
NVQUIRK_DISABLE_SDR104 |
NVQUIRK_SHADOW_XFER_MODE_REG,
};
static const struct of_device_id sdhci_tegra_dt_match[] = {