diff mbox series

[1/3] mmc: sdhci-cadence: enable v4_mode to fix ADMA 64-bit addressing

Message ID 20190829104928.27404-1-yamada.masahiro@socionext.com (mailing list archive)
State New, archived
Headers show
Series [1/3] mmc: sdhci-cadence: enable v4_mode to fix ADMA 64-bit addressing | expand

Commit Message

Masahiro Yamada Aug. 29, 2019, 10:49 a.m. UTC
The IP datasheet says this controller is compatible with SD Host
Specification Version v4.00.

As it turned out, the ADMA of this IP does not work with 64-bit mode
when it is in the Version 3.00 compatible mode; it understands the
old 64-bit descriptor table (as defined in SDHCI v2), but the ADMA
System Address Register (SDHCI_ADMA_ADDRESS) cannot point to the
64-bit address.

I noticed this issue only after commit bd2e75633c80 ("dma-contiguous:
use fallback alloc_pages for single pages"). Prior to that commit,
dma_set_mask_and_coherent() returned the dma address that fits in
32-bit range, at least for the default arm64 configuration
(arch/arm64/configs/defconfig). Now the host->adma_addr exceeds the
32-bit limit, causing the real problem for the Socionext SoCs.
(As a side-note, I was also able to reproduce the issue for older
kernels by turning off CONFIG_DMA_CMA.)

Call sdhci_enable_v4_mode() to fix this.

I think it is better to back-port this, but only possible for v4.20+.

When this driver was merged (v4.10), the v4 mode support did not exist.
It was added by commit b3f80b434f72 ("mmc: sdhci: Add sd host v4 mode")
i.e. v4.20.

Cc: <stable@vger.kernel.org> # v4.20+
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
---

 drivers/mmc/host/sdhci-cadence.c | 1 +
 1 file changed, 1 insertion(+)

Comments

Ulf Hansson Aug. 29, 2019, 11:47 a.m. UTC | #1
On Thu, 29 Aug 2019 at 12:49, Masahiro Yamada
<yamada.masahiro@socionext.com> wrote:
>
> The IP datasheet says this controller is compatible with SD Host
> Specification Version v4.00.
>
> As it turned out, the ADMA of this IP does not work with 64-bit mode
> when it is in the Version 3.00 compatible mode; it understands the
> old 64-bit descriptor table (as defined in SDHCI v2), but the ADMA
> System Address Register (SDHCI_ADMA_ADDRESS) cannot point to the
> 64-bit address.
>
> I noticed this issue only after commit bd2e75633c80 ("dma-contiguous:
> use fallback alloc_pages for single pages"). Prior to that commit,
> dma_set_mask_and_coherent() returned the dma address that fits in
> 32-bit range, at least for the default arm64 configuration
> (arch/arm64/configs/defconfig). Now the host->adma_addr exceeds the
> 32-bit limit, causing the real problem for the Socionext SoCs.
> (As a side-note, I was also able to reproduce the issue for older
> kernels by turning off CONFIG_DMA_CMA.)
>
> Call sdhci_enable_v4_mode() to fix this.
>
> I think it is better to back-port this, but only possible for v4.20+.
>
> When this driver was merged (v4.10), the v4 mode support did not exist.
> It was added by commit b3f80b434f72 ("mmc: sdhci: Add sd host v4 mode")
> i.e. v4.20.
>
> Cc: <stable@vger.kernel.org> # v4.20+
> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Applied for fixes, by adding below tag, thanks!

Fixes: b3f80b434f72 ("mmc: sdhci: Add sd host v4 mode")

Kind regards
Uffe

> ---
>
>  drivers/mmc/host/sdhci-cadence.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/drivers/mmc/host/sdhci-cadence.c b/drivers/mmc/host/sdhci-cadence.c
> index 163d1cf4367e..44139fceac24 100644
> --- a/drivers/mmc/host/sdhci-cadence.c
> +++ b/drivers/mmc/host/sdhci-cadence.c
> @@ -369,6 +369,7 @@ static int sdhci_cdns_probe(struct platform_device *pdev)
>         host->mmc_host_ops.execute_tuning = sdhci_cdns_execute_tuning;
>         host->mmc_host_ops.hs400_enhanced_strobe =
>                                 sdhci_cdns_hs400_enhanced_strobe;
> +       sdhci_enable_v4_mode(host);
>
>         sdhci_get_of_property(pdev);
>
> --
> 2.17.1
>
Masahiro Yamada Aug. 29, 2019, 12:05 p.m. UTC | #2
On Thu, Aug 29, 2019 at 8:48 PM Ulf Hansson <ulf.hansson@linaro.org> wrote:
>
> On Thu, 29 Aug 2019 at 12:49, Masahiro Yamada
> <yamada.masahiro@socionext.com> wrote:
> >
> > The IP datasheet says this controller is compatible with SD Host
> > Specification Version v4.00.
> >
> > As it turned out, the ADMA of this IP does not work with 64-bit mode
> > when it is in the Version 3.00 compatible mode; it understands the
> > old 64-bit descriptor table (as defined in SDHCI v2), but the ADMA
> > System Address Register (SDHCI_ADMA_ADDRESS) cannot point to the
> > 64-bit address.
> >
> > I noticed this issue only after commit bd2e75633c80 ("dma-contiguous:
> > use fallback alloc_pages for single pages"). Prior to that commit,
> > dma_set_mask_and_coherent() returned the dma address that fits in
> > 32-bit range, at least for the default arm64 configuration
> > (arch/arm64/configs/defconfig). Now the host->adma_addr exceeds the
> > 32-bit limit, causing the real problem for the Socionext SoCs.
> > (As a side-note, I was also able to reproduce the issue for older
> > kernels by turning off CONFIG_DMA_CMA.)
> >
> > Call sdhci_enable_v4_mode() to fix this.
> >
> > I think it is better to back-port this, but only possible for v4.20+.
> >
> > When this driver was merged (v4.10), the v4 mode support did not exist.
> > It was added by commit b3f80b434f72 ("mmc: sdhci: Add sd host v4 mode")
> > i.e. v4.20.
> >
> > Cc: <stable@vger.kernel.org> # v4.20+
> > Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
>
> Applied for fixes, by adding below tag, thanks!
>
> Fixes: b3f80b434f72 ("mmc: sdhci: Add sd host v4 mode")

This is not a bug commit.
Ulf Hansson Aug. 29, 2019, 1:27 p.m. UTC | #3
On Thu, 29 Aug 2019 at 14:05, Masahiro Yamada
<yamada.masahiro@socionext.com> wrote:
>
> On Thu, Aug 29, 2019 at 8:48 PM Ulf Hansson <ulf.hansson@linaro.org> wrote:
> >
> > On Thu, 29 Aug 2019 at 12:49, Masahiro Yamada
> > <yamada.masahiro@socionext.com> wrote:
> > >
> > > The IP datasheet says this controller is compatible with SD Host
> > > Specification Version v4.00.
> > >
> > > As it turned out, the ADMA of this IP does not work with 64-bit mode
> > > when it is in the Version 3.00 compatible mode; it understands the
> > > old 64-bit descriptor table (as defined in SDHCI v2), but the ADMA
> > > System Address Register (SDHCI_ADMA_ADDRESS) cannot point to the
> > > 64-bit address.
> > >
> > > I noticed this issue only after commit bd2e75633c80 ("dma-contiguous:
> > > use fallback alloc_pages for single pages"). Prior to that commit,
> > > dma_set_mask_and_coherent() returned the dma address that fits in
> > > 32-bit range, at least for the default arm64 configuration
> > > (arch/arm64/configs/defconfig). Now the host->adma_addr exceeds the
> > > 32-bit limit, causing the real problem for the Socionext SoCs.
> > > (As a side-note, I was also able to reproduce the issue for older
> > > kernels by turning off CONFIG_DMA_CMA.)
> > >
> > > Call sdhci_enable_v4_mode() to fix this.
> > >
> > > I think it is better to back-port this, but only possible for v4.20+.
> > >
> > > When this driver was merged (v4.10), the v4 mode support did not exist.
> > > It was added by commit b3f80b434f72 ("mmc: sdhci: Add sd host v4 mode")
> > > i.e. v4.20.
> > >
> > > Cc: <stable@vger.kernel.org> # v4.20+
> > > Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
> >
> > Applied for fixes, by adding below tag, thanks!
> >
> > Fixes: b3f80b434f72 ("mmc: sdhci: Add sd host v4 mode")
>
> This is not a bug commit.

Right, but it can't be applied before this commit, hence why I added
it. Not sure that it matters, but I can remove the tag if you
insists!?

Kind regards
Uffe
Masahiro Yamada Aug. 29, 2019, 2:04 p.m. UTC | #4
Hi Ulf,

On Thu, Aug 29, 2019 at 10:27 PM Ulf Hansson <ulf.hansson@linaro.org> wrote:
>
> On Thu, 29 Aug 2019 at 14:05, Masahiro Yamada
> <yamada.masahiro@socionext.com> wrote:
> >
> > On Thu, Aug 29, 2019 at 8:48 PM Ulf Hansson <ulf.hansson@linaro.org> wrote:
> > >
> > > On Thu, 29 Aug 2019 at 12:49, Masahiro Yamada
> > > <yamada.masahiro@socionext.com> wrote:
> > > >
> > > > The IP datasheet says this controller is compatible with SD Host
> > > > Specification Version v4.00.
> > > >
> > > > As it turned out, the ADMA of this IP does not work with 64-bit mode
> > > > when it is in the Version 3.00 compatible mode; it understands the
> > > > old 64-bit descriptor table (as defined in SDHCI v2), but the ADMA
> > > > System Address Register (SDHCI_ADMA_ADDRESS) cannot point to the
> > > > 64-bit address.
> > > >
> > > > I noticed this issue only after commit bd2e75633c80 ("dma-contiguous:
> > > > use fallback alloc_pages for single pages"). Prior to that commit,
> > > > dma_set_mask_and_coherent() returned the dma address that fits in
> > > > 32-bit range, at least for the default arm64 configuration
> > > > (arch/arm64/configs/defconfig). Now the host->adma_addr exceeds the
> > > > 32-bit limit, causing the real problem for the Socionext SoCs.
> > > > (As a side-note, I was also able to reproduce the issue for older
> > > > kernels by turning off CONFIG_DMA_CMA.)
> > > >
> > > > Call sdhci_enable_v4_mode() to fix this.
> > > >
> > > > I think it is better to back-port this, but only possible for v4.20+.
> > > >
> > > > When this driver was merged (v4.10), the v4 mode support did not exist.
> > > > It was added by commit b3f80b434f72 ("mmc: sdhci: Add sd host v4 mode")
> > > > i.e. v4.20.
> > > >
> > > > Cc: <stable@vger.kernel.org> # v4.20+
> > > > Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
> > >
> > > Applied for fixes, by adding below tag, thanks!
> > >
> > > Fixes: b3f80b434f72 ("mmc: sdhci: Add sd host v4 mode")
> >
> > This is not a bug commit.
>
> Right, but it can't be applied before this commit, hence why I added
> it. Not sure that it matters, but I can remove the tag if you
> insists!?

I hesitate to add Fixes to the commit that
did nothing wrong.


I added "Cc: <stable@vger.kernel.org> # v4.20+"
so this is enough for the stable kernel maintainers.
Ulf Hansson Aug. 29, 2019, 2:33 p.m. UTC | #5
On Thu, 29 Aug 2019 at 16:04, Masahiro Yamada
<yamada.masahiro@socionext.com> wrote:
>
> Hi Ulf,
>
> On Thu, Aug 29, 2019 at 10:27 PM Ulf Hansson <ulf.hansson@linaro.org> wrote:
> >
> > On Thu, 29 Aug 2019 at 14:05, Masahiro Yamada
> > <yamada.masahiro@socionext.com> wrote:
> > >
> > > On Thu, Aug 29, 2019 at 8:48 PM Ulf Hansson <ulf.hansson@linaro.org> wrote:
> > > >
> > > > On Thu, 29 Aug 2019 at 12:49, Masahiro Yamada
> > > > <yamada.masahiro@socionext.com> wrote:
> > > > >
> > > > > The IP datasheet says this controller is compatible with SD Host
> > > > > Specification Version v4.00.
> > > > >
> > > > > As it turned out, the ADMA of this IP does not work with 64-bit mode
> > > > > when it is in the Version 3.00 compatible mode; it understands the
> > > > > old 64-bit descriptor table (as defined in SDHCI v2), but the ADMA
> > > > > System Address Register (SDHCI_ADMA_ADDRESS) cannot point to the
> > > > > 64-bit address.
> > > > >
> > > > > I noticed this issue only after commit bd2e75633c80 ("dma-contiguous:
> > > > > use fallback alloc_pages for single pages"). Prior to that commit,
> > > > > dma_set_mask_and_coherent() returned the dma address that fits in
> > > > > 32-bit range, at least for the default arm64 configuration
> > > > > (arch/arm64/configs/defconfig). Now the host->adma_addr exceeds the
> > > > > 32-bit limit, causing the real problem for the Socionext SoCs.
> > > > > (As a side-note, I was also able to reproduce the issue for older
> > > > > kernels by turning off CONFIG_DMA_CMA.)
> > > > >
> > > > > Call sdhci_enable_v4_mode() to fix this.
> > > > >
> > > > > I think it is better to back-port this, but only possible for v4.20+.
> > > > >
> > > > > When this driver was merged (v4.10), the v4 mode support did not exist.
> > > > > It was added by commit b3f80b434f72 ("mmc: sdhci: Add sd host v4 mode")
> > > > > i.e. v4.20.
> > > > >
> > > > > Cc: <stable@vger.kernel.org> # v4.20+
> > > > > Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
> > > >
> > > > Applied for fixes, by adding below tag, thanks!
> > > >
> > > > Fixes: b3f80b434f72 ("mmc: sdhci: Add sd host v4 mode")
> > >
> > > This is not a bug commit.
> >
> > Right, but it can't be applied before this commit, hence why I added
> > it. Not sure that it matters, but I can remove the tag if you
> > insists!?
>
> I hesitate to add Fixes to the commit that
> did nothing wrong.
>
>
> I added "Cc: <stable@vger.kernel.org> # v4.20+"
> so this is enough for the stable kernel maintainers.

Yes, I drop the fixes tag. But as I said, I don't think it's a big deal.

Kind regards
Uffe
diff mbox series

Patch

diff --git a/drivers/mmc/host/sdhci-cadence.c b/drivers/mmc/host/sdhci-cadence.c
index 163d1cf4367e..44139fceac24 100644
--- a/drivers/mmc/host/sdhci-cadence.c
+++ b/drivers/mmc/host/sdhci-cadence.c
@@ -369,6 +369,7 @@  static int sdhci_cdns_probe(struct platform_device *pdev)
 	host->mmc_host_ops.execute_tuning = sdhci_cdns_execute_tuning;
 	host->mmc_host_ops.hs400_enhanced_strobe =
 				sdhci_cdns_hs400_enhanced_strobe;
+	sdhci_enable_v4_mode(host);
 
 	sdhci_get_of_property(pdev);