diff options
| author |   Seungwon Jeon <tgih.jun@samsung.com> | 2011-10-14 14:03:21 +0900 |
|---|---|---|
| committer |   Chris Ball <cjb@laptop.org> | 2011-10-26 16:32:28 -0400 |
| commit | 881d1c25f765938a95def5afe39486ce39f9fc96 (patch) | |
| tree | 694d5ea1b3fba2c28cc110123f2ca50b4408f309 /drivers/mmc/core/mmc.c | |
| parent | mmc: core: Modify the timeout value for writing power class (diff) | |
| download | linux-dev-881d1c25f765938a95def5afe39486ce39f9fc96.tar.xz linux-dev-881d1c25f765938a95def5afe39486ce39f9fc96.zip | |
mmc: core: Add cache control for eMMC4.5 device
This patch adds cache feature of eMMC4.5 Spec.
If device supports cache capability, host can utilize some specific
operations.
Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Diffstat (limited to 'drivers/mmc/core/mmc.c')
| -rw-r--r-- | drivers/mmc/core/mmc.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c index 793901519208..de5900aa81cd 100644 --- a/drivers/mmc/core/mmc.c +++ b/drivers/mmc/core/mmc.c @@ -470,6 +470,12 @@ static int mmc_read_ext_csd(struct mmc_card *card, u8 *ext_csd) } else card->ext_csd.generic_cmd6_time = 0; + card->ext_csd.cache_size = + ext_csd[EXT_CSD_CACHE_SIZE + 0] << 0 | + ext_csd[EXT_CSD_CACHE_SIZE + 1] << 8 | + ext_csd[EXT_CSD_CACHE_SIZE + 2] << 16 | + ext_csd[EXT_CSD_CACHE_SIZE + 3] << 24; + out: return err; } @@ -1020,6 +1026,23 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr, } } + /* + * If cache size is higher than 0, this indicates + * the existence of cache and it can be turned on. + */ + if ((host->caps2 & MMC_CAP2_CACHE_CTRL) && + card->ext_csd.cache_size > 0) { + err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, + EXT_CSD_CACHE_CTRL, 1, 0); + if (err && err != -EBADMSG) + goto free_card; + + /* + * Only if no error, cache is turned on successfully. + */ + card->ext_csd.cache_ctrl = err ? 0 : 1; + } + if (!oldcard) host->card = card; |