| Message ID | 1529028255-6022-2-git-send-email-zhang.chunyan@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 15/06/18 05:04, Chunyan Zhang wrote: > For SD host controller version 4.00 or later ones, there're two > modes of implementation - Version 3.00 compatible mode or > Version 4 mode. This patch introduces a flag to record this. > > Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org> > --- > drivers/mmc/host/sdhci.c | 6 ++++++ > drivers/mmc/host/sdhci.h | 6 ++++++ > 2 files changed, 12 insertions(+) > > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c > index 2ededa7f..cf5695f 100644 > --- a/drivers/mmc/host/sdhci.c > +++ b/drivers/mmc/host/sdhci.c > @@ -3302,6 +3302,12 @@ void __sdhci_read_caps(struct sdhci_host *host, u16 *ver, u32 *caps, u32 *caps1) > v = ver ? *ver : sdhci_readw(host, SDHCI_HOST_VERSION); > host->version = (v & SDHCI_SPEC_VER_MASK) >> SDHCI_SPEC_VER_SHIFT; > > + if (host->version >= SDHCI_SPEC_400) { > + if (sdhci_readw(host, SDHCI_HOST_CONTROL2) & > + SDHCI_CTRL_V4_MODE) > + host->v4_mode = true; > + } At this point the host controller has just been reset which would mean it must be in version 3 compatibility mode, which would mean this code doesn't do anything. > + > if (host->quirks & SDHCI_QUIRK_MISSING_CAPS) > return; > > diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h > index c95b0a4..128b0ba 100644 > --- a/drivers/mmc/host/sdhci.h > +++ b/drivers/mmc/host/sdhci.h > @@ -184,6 +184,7 @@ > #define SDHCI_CTRL_DRV_TYPE_D 0x0030 > #define SDHCI_CTRL_EXEC_TUNING 0x0040 > #define SDHCI_CTRL_TUNED_CLK 0x0080 > +#define SDHCI_CTRL_V4_MODE 0x1000 > #define SDHCI_CTRL_PRESET_VAL_ENABLE 0x8000 > > #define SDHCI_CAPABILITIES 0x40 > @@ -270,6 +271,8 @@ > #define SDHCI_SPEC_100 0 > #define SDHCI_SPEC_200 1 > #define SDHCI_SPEC_300 2 > +#define SDHCI_SPEC_400 3 > +#define SDHCI_SPEC_410 4 > > /* > * End of controller registers. > @@ -551,6 +554,9 @@ struct sdhci_host { > u32 sdma_boundary; > > unsigned long private[0] ____cacheline_aligned; > + > + /* Host Version 4 Enable */ > + bool v4_mode; > }; > > struct sdhci_ops { > -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 21 June 2018 at 18:49, Adrian Hunter <adrian.hunter@intel.com> wrote: > On 15/06/18 05:04, Chunyan Zhang wrote: >> For SD host controller version 4.00 or later ones, there're two >> modes of implementation - Version 3.00 compatible mode or >> Version 4 mode. This patch introduces a flag to record this. >> >> Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org> >> --- >> drivers/mmc/host/sdhci.c | 6 ++++++ >> drivers/mmc/host/sdhci.h | 6 ++++++ >> 2 files changed, 12 insertions(+) >> >> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c >> index 2ededa7f..cf5695f 100644 >> --- a/drivers/mmc/host/sdhci.c >> +++ b/drivers/mmc/host/sdhci.c >> @@ -3302,6 +3302,12 @@ void __sdhci_read_caps(struct sdhci_host *host, u16 *ver, u32 *caps, u32 *caps1) >> v = ver ? *ver : sdhci_readw(host, SDHCI_HOST_VERSION); >> host->version = (v & SDHCI_SPEC_VER_MASK) >> SDHCI_SPEC_VER_SHIFT; >> >> + if (host->version >= SDHCI_SPEC_400) { >> + if (sdhci_readw(host, SDHCI_HOST_CONTROL2) & >> + SDHCI_CTRL_V4_MODE) >> + host->v4_mode = true; >> + } > > At this point the host controller has just been reset which would mean it > must be in version 3 compatibility mode, which would mean this code doesn't > do anything. Why is it version 3 mode at this point? I've tested this code on the sd host controller which was introduced in 6/7 in this patch-set, the result showed that it was v4_mode. Moreover without this patch, the Spreadtrum's sdhci driver in patch 6/7 couldn't work. Am I missing something here? Best, Chunyan > >> + >> if (host->quirks & SDHCI_QUIRK_MISSING_CAPS) >> return; >> >> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h >> index c95b0a4..128b0ba 100644 >> --- a/drivers/mmc/host/sdhci.h >> +++ b/drivers/mmc/host/sdhci.h >> @@ -184,6 +184,7 @@ >> #define SDHCI_CTRL_DRV_TYPE_D 0x0030 >> #define SDHCI_CTRL_EXEC_TUNING 0x0040 >> #define SDHCI_CTRL_TUNED_CLK 0x0080 >> +#define SDHCI_CTRL_V4_MODE 0x1000 >> #define SDHCI_CTRL_PRESET_VAL_ENABLE 0x8000 >> >> #define SDHCI_CAPABILITIES 0x40 >> @@ -270,6 +271,8 @@ >> #define SDHCI_SPEC_100 0 >> #define SDHCI_SPEC_200 1 >> #define SDHCI_SPEC_300 2 >> +#define SDHCI_SPEC_400 3 >> +#define SDHCI_SPEC_410 4 >> >> /* >> * End of controller registers. >> @@ -551,6 +554,9 @@ struct sdhci_host { >> u32 sdma_boundary; >> >> unsigned long private[0] ____cacheline_aligned; >> + >> + /* Host Version 4 Enable */ >> + bool v4_mode; >> }; >> >> struct sdhci_ops { >> > -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 21/06/18 14:14, Chunyan Zhang wrote: > On 21 June 2018 at 18:49, Adrian Hunter <adrian.hunter@intel.com> wrote: >> On 15/06/18 05:04, Chunyan Zhang wrote: >>> For SD host controller version 4.00 or later ones, there're two >>> modes of implementation - Version 3.00 compatible mode or >>> Version 4 mode. This patch introduces a flag to record this. >>> >>> Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org> >>> --- >>> drivers/mmc/host/sdhci.c | 6 ++++++ >>> drivers/mmc/host/sdhci.h | 6 ++++++ >>> 2 files changed, 12 insertions(+) >>> >>> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c >>> index 2ededa7f..cf5695f 100644 >>> --- a/drivers/mmc/host/sdhci.c >>> +++ b/drivers/mmc/host/sdhci.c >>> @@ -3302,6 +3302,12 @@ void __sdhci_read_caps(struct sdhci_host *host, u16 *ver, u32 *caps, u32 *caps1) >>> v = ver ? *ver : sdhci_readw(host, SDHCI_HOST_VERSION); >>> host->version = (v & SDHCI_SPEC_VER_MASK) >> SDHCI_SPEC_VER_SHIFT; >>> >>> + if (host->version >= SDHCI_SPEC_400) { >>> + if (sdhci_readw(host, SDHCI_HOST_CONTROL2) & >>> + SDHCI_CTRL_V4_MODE) >>> + host->v4_mode = true; >>> + } >> >> At this point the host controller has just been reset which would mean it >> must be in version 3 compatibility mode, which would mean this code doesn't >> do anything. > > Why is it version 3 mode at this point? According to the specification, reset clears RW fields to zero. > > I've tested this code on the sd host controller which was introduced > in 6/7 in this patch-set, the result showed that it was v4_mode. > Moreover without this patch, the Spreadtrum's sdhci driver in patch > 6/7 couldn't work. > > Am I missing something here? It seems the Spreadtrum controller doesn't clear the "Host Version 4 Enable" bit upon software reset for all. Also this seems the wrong way around. The driver should decide whether or not to use V4 mode and then the "Host Version 4 Enable" bit should be set accordingly. V4 has been around so long that we can't just enable all supporting hardware without risking the possibility it will break some platform. So I suggest adding a function sdhci_enable_v4_mode() which is called during probe. > > Best, > Chunyan > >> >>> + >>> if (host->quirks & SDHCI_QUIRK_MISSING_CAPS) >>> return; >>> >>> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h >>> index c95b0a4..128b0ba 100644 >>> --- a/drivers/mmc/host/sdhci.h >>> +++ b/drivers/mmc/host/sdhci.h >>> @@ -184,6 +184,7 @@ >>> #define SDHCI_CTRL_DRV_TYPE_D 0x0030 >>> #define SDHCI_CTRL_EXEC_TUNING 0x0040 >>> #define SDHCI_CTRL_TUNED_CLK 0x0080 >>> +#define SDHCI_CTRL_V4_MODE 0x1000 >>> #define SDHCI_CTRL_PRESET_VAL_ENABLE 0x8000 >>> >>> #define SDHCI_CAPABILITIES 0x40 >>> @@ -270,6 +271,8 @@ >>> #define SDHCI_SPEC_100 0 >>> #define SDHCI_SPEC_200 1 >>> #define SDHCI_SPEC_300 2 >>> +#define SDHCI_SPEC_400 3 >>> +#define SDHCI_SPEC_410 4 >>> >>> /* >>> * End of controller registers. >>> @@ -551,6 +554,9 @@ struct sdhci_host { >>> u32 sdma_boundary; >>> >>> unsigned long private[0] ____cacheline_aligned; >>> + >>> + /* Host Version 4 Enable */ >>> + bool v4_mode; >>> }; >>> >>> struct sdhci_ops { >>> >> > -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 21 June 2018 at 21:15, Adrian Hunter <adrian.hunter@intel.com> wrote: > On 21/06/18 14:14, Chunyan Zhang wrote: >> On 21 June 2018 at 18:49, Adrian Hunter <adrian.hunter@intel.com> wrote: >>> On 15/06/18 05:04, Chunyan Zhang wrote: >>>> For SD host controller version 4.00 or later ones, there're two >>>> modes of implementation - Version 3.00 compatible mode or >>>> Version 4 mode. This patch introduces a flag to record this. >>>> >>>> Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org> >>>> --- >>>> drivers/mmc/host/sdhci.c | 6 ++++++ >>>> drivers/mmc/host/sdhci.h | 6 ++++++ >>>> 2 files changed, 12 insertions(+) >>>> >>>> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c >>>> index 2ededa7f..cf5695f 100644 >>>> --- a/drivers/mmc/host/sdhci.c >>>> +++ b/drivers/mmc/host/sdhci.c >>>> @@ -3302,6 +3302,12 @@ void __sdhci_read_caps(struct sdhci_host *host, u16 *ver, u32 *caps, u32 *caps1) >>>> v = ver ? *ver : sdhci_readw(host, SDHCI_HOST_VERSION); >>>> host->version = (v & SDHCI_SPEC_VER_MASK) >> SDHCI_SPEC_VER_SHIFT; >>>> >>>> + if (host->version >= SDHCI_SPEC_400) { >>>> + if (sdhci_readw(host, SDHCI_HOST_CONTROL2) & >>>> + SDHCI_CTRL_V4_MODE) >>>> + host->v4_mode = true; >>>> + } >>> >>> At this point the host controller has just been reset which would mean it >>> must be in version 3 compatibility mode, which would mean this code doesn't >>> do anything. >> >> Why is it version 3 mode at this point? > > According to the specification, reset clears RW fields to zero. > >> >> I've tested this code on the sd host controller which was introduced >> in 6/7 in this patch-set, the result showed that it was v4_mode. >> Moreover without this patch, the Spreadtrum's sdhci driver in patch >> 6/7 couldn't work. >> >> Am I missing something here? > > It seems the Spreadtrum controller doesn't clear the "Host Version 4 Enable" > bit upon software reset for all. > > Also this seems the wrong way around. The driver should decide whether or > not to use V4 mode and then the "Host Version 4 Enable" bit should be set > accordingly. > > V4 has been around so long that we can't just enable all supporting hardware > without risking the possibility it will break some platform. So I suggest Ok, understand. > adding a function sdhci_enable_v4_mode() which is called during probe. Ok, will do, that is more a safe way. > >> >> Best, >> Chunyan >> >>> >>>> + >>>> if (host->quirks & SDHCI_QUIRK_MISSING_CAPS) >>>> return; >>>> >>>> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h >>>> index c95b0a4..128b0ba 100644 >>>> --- a/drivers/mmc/host/sdhci.h >>>> +++ b/drivers/mmc/host/sdhci.h >>>> @@ -184,6 +184,7 @@ >>>> #define SDHCI_CTRL_DRV_TYPE_D 0x0030 >>>> #define SDHCI_CTRL_EXEC_TUNING 0x0040 >>>> #define SDHCI_CTRL_TUNED_CLK 0x0080 >>>> +#define SDHCI_CTRL_V4_MODE 0x1000 >>>> #define SDHCI_CTRL_PRESET_VAL_ENABLE 0x8000 >>>> >>>> #define SDHCI_CAPABILITIES 0x40 >>>> @@ -270,6 +271,8 @@ >>>> #define SDHCI_SPEC_100 0 >>>> #define SDHCI_SPEC_200 1 >>>> #define SDHCI_SPEC_300 2 >>>> +#define SDHCI_SPEC_400 3 >>>> +#define SDHCI_SPEC_410 4 >>>> >>>> /* >>>> * End of controller registers. >>>> @@ -551,6 +554,9 @@ struct sdhci_host { >>>> u32 sdma_boundary; >>>> >>>> unsigned long private[0] ____cacheline_aligned; >>>> + >>>> + /* Host Version 4 Enable */ >>>> + bool v4_mode; >>>> }; >>>> >>>> struct sdhci_ops { >>>> >>> >> > -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c index 2ededa7f..cf5695f 100644 --- a/drivers/mmc/host/sdhci.c +++ b/drivers/mmc/host/sdhci.c @@ -3302,6 +3302,12 @@ void __sdhci_read_caps(struct sdhci_host *host, u16 *ver, u32 *caps, u32 *caps1) v = ver ? *ver : sdhci_readw(host, SDHCI_HOST_VERSION); host->version = (v & SDHCI_SPEC_VER_MASK) >> SDHCI_SPEC_VER_SHIFT; + if (host->version >= SDHCI_SPEC_400) { + if (sdhci_readw(host, SDHCI_HOST_CONTROL2) & + SDHCI_CTRL_V4_MODE) + host->v4_mode = true; + } + if (host->quirks & SDHCI_QUIRK_MISSING_CAPS) return; diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h index c95b0a4..128b0ba 100644 --- a/drivers/mmc/host/sdhci.h +++ b/drivers/mmc/host/sdhci.h @@ -184,6 +184,7 @@ #define SDHCI_CTRL_DRV_TYPE_D 0x0030 #define SDHCI_CTRL_EXEC_TUNING 0x0040 #define SDHCI_CTRL_TUNED_CLK 0x0080 +#define SDHCI_CTRL_V4_MODE 0x1000 #define SDHCI_CTRL_PRESET_VAL_ENABLE 0x8000 #define SDHCI_CAPABILITIES 0x40 @@ -270,6 +271,8 @@ #define SDHCI_SPEC_100 0 #define SDHCI_SPEC_200 1 #define SDHCI_SPEC_300 2 +#define SDHCI_SPEC_400 3 +#define SDHCI_SPEC_410 4 /* * End of controller registers. @@ -551,6 +554,9 @@ struct sdhci_host { u32 sdma_boundary; unsigned long private[0] ____cacheline_aligned; + + /* Host Version 4 Enable */ + bool v4_mode; }; struct sdhci_ops {
For SD host controller version 4.00 or later ones, there're two modes of implementation - Version 3.00 compatible mode or Version 4 mode. This patch introduces a flag to record this. Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org> --- drivers/mmc/host/sdhci.c | 6 ++++++ drivers/mmc/host/sdhci.h | 6 ++++++ 2 files changed, 12 insertions(+)