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| author | Arindam Nath <arindam.nath@amd.com> | 2011-05-05 12:18:59 +0530 |
|---|---|---|
| committer | Chris Ball <cjb@laptop.org> | 2011-05-24 23:53:24 -0400 |
| commit | d6d50a15a2897d4133d536dd4343b5cf21163db3 (patch) | |
| tree | b56723c1b3e74ae2ae9e9d7fb39e916cdfa74958 /drivers/mmc/host | |
| parent | 013909c4ffd16ded4895528b856fd8782df04dc6 (diff) | |
| download | linux-d6d50a15a2897d4133d536dd4343b5cf21163db3.tar.gz linux-d6d50a15a2897d4133d536dd4343b5cf21163db3.tar.bz2 linux-d6d50a15a2897d4133d536dd4343b5cf21163db3.zip | |
mmc: sd: add support for driver type selection
This patch adds support for setting driver strength during UHS-I
initialization procedure. Since UHS-I cards set S18A (bit 24) in
response to ACMD41, we use this as a base for UHS-I initialization.
We modify the parameter list of mmc_sd_get_cid() so that we can
save the ROCR from ACMD41 to check whether bit 24 is set.
We decide whether the Host Controller supports A, C, or D driver
type depending on the Capabilities register. Driver type B is
suported by default. We then set the appropriate driver type for
the card using CMD6 mode 1. As per Host Controller spec v3.00, we
set driver type for the host only if Preset Value Enable in the
Host Control2 register is not set. SDHCI_HOST_CONTROL has been
renamed to SDHCI_HOST_CONTROL1 to conform to the spec.
Tested by Zhangfei Gao with a Toshiba uhs card and general hs card,
on mmp2 in SDMA mode.
Signed-off-by: Arindam Nath <arindam.nath@amd.com>
Reviewed-by: Philip Rakity <prakity@marvell.com>
Tested-by: Philip Rakity <prakity@marvell.com>
Acked-by: Zhangfei Gao <zhangfei.gao@marvell.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Diffstat (limited to 'drivers/mmc/host')
| -rw-r--r-- | drivers/mmc/host/sdhci.c | 27 | ||||
| -rw-r--r-- | drivers/mmc/host/sdhci.h | 11 |
2 files changed, 37 insertions, 1 deletions
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 4e2031449a23..8072e16d6d46 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -1245,6 +1245,25 @@ static void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL); + if (host->version >= SDHCI_SPEC_300) { + u16 ctrl_2; + + ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2); + if (!(ctrl_2 & SDHCI_CTRL_PRESET_VAL_ENABLE)) { + /* + * We only need to set Driver Strength if the + * preset value enable is not set. + */ + ctrl_2 &= ~SDHCI_CTRL_DRV_TYPE_MASK; + if (ios->drv_type == MMC_SET_DRIVER_TYPE_A) + ctrl_2 |= SDHCI_CTRL_DRV_TYPE_A; + else if (ios->drv_type == MMC_SET_DRIVER_TYPE_C) + ctrl_2 |= SDHCI_CTRL_DRV_TYPE_C; + + sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2); + } + } + /* * Some (ENE) controllers go apeshit on some ios operation, * signalling timeout and CRC errors even on CMD0. Resetting @@ -2086,6 +2105,14 @@ int sdhci_add_host(struct sdhci_host *host) if (caps[1] & SDHCI_SUPPORT_DDR50) mmc->caps |= MMC_CAP_UHS_DDR50; + /* Driver Type(s) (A, C, D) supported by the host */ + if (caps[1] & SDHCI_DRIVER_TYPE_A) + mmc->caps |= MMC_CAP_DRIVER_TYPE_A; + if (caps[1] & SDHCI_DRIVER_TYPE_C) + mmc->caps |= MMC_CAP_DRIVER_TYPE_C; + if (caps[1] & SDHCI_DRIVER_TYPE_D) + mmc->caps |= MMC_CAP_DRIVER_TYPE_D; + ocr_avail = 0; /* * According to SD Host Controller spec v3.00, if the Host System diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h index 5cba2fea46e0..667bf8874be7 100644 --- a/drivers/mmc/host/sdhci.h +++ b/drivers/mmc/host/sdhci.h @@ -71,7 +71,7 @@ #define SDHCI_DATA_LVL_MASK 0x00F00000 #define SDHCI_DATA_LVL_SHIFT 20 -#define SDHCI_HOST_CONTROL 0x28 +#define SDHCI_HOST_CONTROL 0x28 #define SDHCI_CTRL_LED 0x01 #define SDHCI_CTRL_4BITBUS 0x02 #define SDHCI_CTRL_HISPD 0x04 @@ -150,6 +150,12 @@ #define SDHCI_HOST_CONTROL2 0x3E #define SDHCI_CTRL_VDD_180 0x0008 +#define SDHCI_CTRL_DRV_TYPE_MASK 0x0030 +#define SDHCI_CTRL_DRV_TYPE_B 0x0000 +#define SDHCI_CTRL_DRV_TYPE_A 0x0010 +#define SDHCI_CTRL_DRV_TYPE_C 0x0020 +#define SDHCI_CTRL_DRV_TYPE_D 0x0030 +#define SDHCI_CTRL_PRESET_VAL_ENABLE 0x8000 #define SDHCI_CAPABILITIES 0x40 #define SDHCI_TIMEOUT_CLK_MASK 0x0000003F @@ -173,6 +179,9 @@ #define SDHCI_SUPPORT_SDR50 0x00000001 #define SDHCI_SUPPORT_SDR104 0x00000002 #define SDHCI_SUPPORT_DDR50 0x00000004 +#define SDHCI_DRIVER_TYPE_A 0x00000010 +#define SDHCI_DRIVER_TYPE_C 0x00000020 +#define SDHCI_DRIVER_TYPE_D 0x00000040 #define SDHCI_CAPABILITIES_1 0x44 |