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mmc: sdhci-esdhc-imx: add DDR mode support for mx6

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When DDR mode is enabled, the initial pre_div should be 2.
And the pre_div value should be changed accordingly
from
...
02h) Base clock divided by 4
01h) Base clock divided by 2
00h) Base clock divided by 1
to
..
02h) Base clock divided by 8
01h) Base clock divided by 4
00h) Base clock divided by 2

Signed-off-by: Dong Aisheng <b29396@freescale.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
This commit is contained in:
Dong Aisheng 2013-10-18 19:48:46 +08:00 committed by Chris Ball
parent 114f2bf6a1
commit de5bdbffd8
1 changed files with 14 additions and 3 deletions
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17
drivers/mmc/host/sdhci-esdhc-imx.c
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@ -38,6 +38,7 @@
#define ESDHC_VENDOR_SPEC_FRC_SDCLK_ON (1 << 8)
#define ESDHC_WTMK_LVL 0x44
#define ESDHC_MIX_CTRL 0x48
#define ESDHC_MIX_CTRL_DDREN (1 << 3)
#define ESDHC_MIX_CTRL_AC23EN (1 << 7)
#define ESDHC_MIX_CTRL_EXE_TUNE (1 << 22)
#define ESDHC_MIX_CTRL_SMPCLK_SEL (1 << 23)
@ -152,6 +153,7 @@ struct pltfm_imx_data {
WAIT_FOR_INT, /* sent CMD12, waiting for response INT */
} multiblock_status;
u32 uhs_mode;
u32 is_ddr;
};
static struct platform_device_id imx_esdhc_devtype[] = {
@ -537,8 +539,10 @@ static void esdhc_writeb_le(struct sdhci_host *host, u8 val, int reg)
* The reset on usdhc fails to clear MIX_CTRL register.
* Do it manually here.
*/
if (esdhc_is_usdhc(imx_data))
if (esdhc_is_usdhc(imx_data)) {
writel(0, host->ioaddr + ESDHC_MIX_CTRL);
imx_data->is_ddr = 0;
}
}
}
@ -582,7 +586,7 @@ static inline void esdhc_pltfm_set_clock(struct sdhci_host *host,
goto out;
}
if (esdhc_is_usdhc(imx_data))
if (esdhc_is_usdhc(imx_data) && !imx_data->is_ddr)
pre_div = 1;
temp = sdhci_readl(host, ESDHC_SYSTEM_CONTROL);
@ -600,7 +604,10 @@ static inline void esdhc_pltfm_set_clock(struct sdhci_host *host,
dev_dbg(mmc_dev(host->mmc), "desired SD clock: %d, actual: %d\n",
clock, host->mmc->actual_clock);
pre_div >>= 1;
if (imx_data->is_ddr)
pre_div >>= 2;
else
pre_div >>= 1;
div--;
temp = sdhci_readl(host, ESDHC_SYSTEM_CONTROL);
@ -826,6 +833,10 @@ static int esdhc_set_uhs_signaling(struct sdhci_host *host, unsigned int uhs)
break;
case MMC_TIMING_UHS_DDR50:
imx_data->uhs_mode = SDHCI_CTRL_UHS_DDR50;
writel(readl(host->ioaddr + ESDHC_MIX_CTRL) |
ESDHC_MIX_CTRL_DDREN,
host->ioaddr + ESDHC_MIX_CTRL);
imx_data->is_ddr = 1;
break;
}