| Message ID | 20190513091548.16674-2-narmstrong@baylibre.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | mmc: meson-gx: add ddr-access-quirk support | expand |
Hi Neil, On Mon, May 13, 2019 at 11:16 AM Neil Armstrong <narmstrong@baylibre.com> wrote: > > On the Amlogic G12A SoC family, (only) the SDIO controller has a bug which > makes any DDR access from the MMC controller fail. > > Add the amlogic,ddr-access-quirk property so signal this particular > controller has this bug and needs a quirk to work properly. > > Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> > --- > Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt b/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt > index 13e70409e8ac..f8914dab06c6 100644 > --- a/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt > +++ b/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt > @@ -22,6 +22,10 @@ Required properties: > clock rate requested by the MMC core. > - resets : phandle of the internal reset line > > +Optional properties: > +- amlogic,ddr-access-quirk: set when HW cannot access the DDR memory, like on > + the G12A SDIO controller. (I believe we cannot use a standard property like "dma-ranges" to disable DMA access) personally I prefer "amlogic,no-direct-memory-access" or "amlogic,no-ddr-access", but if Rob is happy with the current naming then I'm happy as well Regards Martin
On Mon, 13 May 2019 at 11:16, Neil Armstrong <narmstrong@baylibre.com> wrote: > > On the Amlogic G12A SoC family, (only) the SDIO controller has a bug which > makes any DDR access from the MMC controller fail. > > Add the amlogic,ddr-access-quirk property so signal this particular > controller has this bug and needs a quirk to work properly. > > Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> > --- > Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt b/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt > index 13e70409e8ac..f8914dab06c6 100644 > --- a/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt > +++ b/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt > @@ -22,6 +22,10 @@ Required properties: > clock rate requested by the MMC core. > - resets : phandle of the internal reset line > > +Optional properties: > +- amlogic,ddr-access-quirk: set when HW cannot access the DDR memory, like on > + the G12A SDIO controller. As stated on the other patch, may I suggest to use DRAM instead of DDR. Moreover, please mention that this is about the internal DMA support of the controller. > + > Example: > > sd_emmc_a: mmc@70000 { > -- > 2.21.0 > Kind regards Uffe
On 14/05/2019 19:50, Martin Blumenstingl wrote: > Hi Neil, > > On Mon, May 13, 2019 at 11:16 AM Neil Armstrong <narmstrong@baylibre.com> wrote: >> >> On the Amlogic G12A SoC family, (only) the SDIO controller has a bug which >> makes any DDR access from the MMC controller fail. >> >> Add the amlogic,ddr-access-quirk property so signal this particular >> controller has this bug and needs a quirk to work properly. >> >> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> > Reviewed-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> > >> --- >> Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt | 4 ++++ >> 1 file changed, 4 insertions(+) >> >> diff --git a/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt b/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt >> index 13e70409e8ac..f8914dab06c6 100644 >> --- a/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt >> +++ b/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt >> @@ -22,6 +22,10 @@ Required properties: >> clock rate requested by the MMC core. >> - resets : phandle of the internal reset line >> >> +Optional properties: >> +- amlogic,ddr-access-quirk: set when HW cannot access the DDR memory, like on >> + the G12A SDIO controller. > (I believe we cannot use a standard property like "dma-ranges" to > disable DMA access) > personally I prefer "amlogic,no-direct-memory-access" or > "amlogic,no-ddr-access", but if Rob is happy with the current naming > then I'm happy as well I have no preference, I can change it easily, Neil > > > Regards > Martin >
On 15/05/2019 13:37, Ulf Hansson wrote: > On Mon, 13 May 2019 at 11:16, Neil Armstrong <narmstrong@baylibre.com> wrote: >> >> On the Amlogic G12A SoC family, (only) the SDIO controller has a bug which >> makes any DDR access from the MMC controller fail. >> >> Add the amlogic,ddr-access-quirk property so signal this particular >> controller has this bug and needs a quirk to work properly. >> >> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> >> --- >> Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt | 4 ++++ >> 1 file changed, 4 insertions(+) >> >> diff --git a/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt b/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt >> index 13e70409e8ac..f8914dab06c6 100644 >> --- a/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt >> +++ b/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt >> @@ -22,6 +22,10 @@ Required properties: >> clock rate requested by the MMC core. >> - resets : phandle of the internal reset line >> >> +Optional properties: >> +- amlogic,ddr-access-quirk: set when HW cannot access the DDR memory, like on >> + the G12A SDIO controller. > > As stated on the other patch, may I suggest to use DRAM instead of DDR. Indeed, may be more accurate. > > Moreover, please mention that this is about the internal DMA support > of the controller. Ok > >> + >> Example: >> >> sd_emmc_a: mmc@70000 { >> -- >> 2.21.0 >> > > Kind regards > Uffe >
diff --git a/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt b/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt index 13e70409e8ac..f8914dab06c6 100644 --- a/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt +++ b/Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt @@ -22,6 +22,10 @@ Required properties: clock rate requested by the MMC core. - resets : phandle of the internal reset line +Optional properties: +- amlogic,ddr-access-quirk: set when HW cannot access the DDR memory, like on + the G12A SDIO controller. + Example: sd_emmc_a: mmc@70000 {
On the Amlogic G12A SoC family, (only) the SDIO controller has a bug which makes any DDR access from the MMC controller fail. Add the amlogic,ddr-access-quirk property so signal this particular controller has this bug and needs a quirk to work properly. Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> --- Documentation/devicetree/bindings/mmc/amlogic,meson-gx.txt | 4 ++++ 1 file changed, 4 insertions(+)