| Message ID | 20210504161222.101536-9-ulf.hansson@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | Initital support for new power/perf features for SD cards | expand |
On Tue, May 4, 2021 at 6:12 PM Ulf Hansson <ulf.hansson@linaro.org> wrote: > In SD spec v4.x the support for CMD48/49 and CMD58/59 were introduced as > optional features. To let the card announce whether it supports the > commands, the SCR register has been extended with corresponding support > bits. Let's parse and store this information for later use. > > Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Yours, Linus Walleij
On 2021/5/5 0:12, Ulf Hansson wrote: > In SD spec v4.x the support for CMD48/49 and CMD58/59 were introduced as > optional features. To let the card announce whether it supports the > commands, the SCR register has been extended with corresponding support > bits. Let's parse and store this information for later use. > Just check v4.0 spec, and it says "Table 4-32 is added in Version 4.00. These commands are reserved for future extenstion". So, Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com> > Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> > --- > drivers/mmc/core/sd.c | 4 +++- > include/linux/mmc/card.h | 2 ++ > 2 files changed, 5 insertions(+), 1 deletion(-) > > diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c > index 2c48d6504101..de7b5f8df550 100644 > --- a/drivers/mmc/core/sd.c > +++ b/drivers/mmc/core/sd.c > @@ -222,7 +222,9 @@ static int mmc_decode_scr(struct mmc_card *card) > else > card->erased_byte = 0x0; > > - if (scr->sda_spec3) > + if (scr->sda_spec4) > + scr->cmds = UNSTUFF_BITS(resp, 32, 4); > + else if (scr->sda_spec3) > scr->cmds = UNSTUFF_BITS(resp, 32, 2); > > /* SD Spec says: any SD Card shall set at least bits 0 and 2 */ > diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h > index f9ad35dd6012..858fc4d11240 100644 > --- a/include/linux/mmc/card.h > +++ b/include/linux/mmc/card.h > @@ -139,6 +139,8 @@ struct sd_scr { > unsigned char cmds; > #define SD_SCR_CMD20_SUPPORT (1<<0) > #define SD_SCR_CMD23_SUPPORT (1<<1) > +#define SD_SCR_CMD48_SUPPORT (1<<2) > +#define SD_SCR_CMD58_SUPPORT (1<<3) > }; > > struct sd_ssr { >
diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c index 2c48d6504101..de7b5f8df550 100644 --- a/drivers/mmc/core/sd.c +++ b/drivers/mmc/core/sd.c @@ -222,7 +222,9 @@ static int mmc_decode_scr(struct mmc_card *card) else card->erased_byte = 0x0; - if (scr->sda_spec3) + if (scr->sda_spec4) + scr->cmds = UNSTUFF_BITS(resp, 32, 4); + else if (scr->sda_spec3) scr->cmds = UNSTUFF_BITS(resp, 32, 2); /* SD Spec says: any SD Card shall set at least bits 0 and 2 */ diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h index f9ad35dd6012..858fc4d11240 100644 --- a/include/linux/mmc/card.h +++ b/include/linux/mmc/card.h @@ -139,6 +139,8 @@ struct sd_scr { unsigned char cmds; #define SD_SCR_CMD20_SUPPORT (1<<0) #define SD_SCR_CMD23_SUPPORT (1<<1) +#define SD_SCR_CMD48_SUPPORT (1<<2) +#define SD_SCR_CMD58_SUPPORT (1<<3) }; struct sd_ssr {
In SD spec v4.x the support for CMD48/49 and CMD58/59 were introduced as optional features. To let the card announce whether it supports the commands, the SCR register has been extended with corresponding support bits. Let's parse and store this information for later use. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> --- drivers/mmc/core/sd.c | 4 +++- include/linux/mmc/card.h | 2 ++ 2 files changed, 5 insertions(+), 1 deletion(-) -- 2.25.1