[U-Boot] [PATCH V2 4/7] video: exynos_fimd: Add framework to disable FIMD sysmmu

[Ajay kumar]

Hi Simon,
>
>
> On Fri, Dec 20, 2013 at 2:09 AM, Simon Glass <sjg at chromium.org> wrote:
>
>> Hi Ajay,
>>
>> On 12 November 2013 05:27, Ajay Kumar <ajaykumar.rs at samsung.com> wrote:
>> > On Exynos5420 and newer versions, the FIMD sysmmus are in
>> > "on state" by default.
>> > We have to disable them in order to make FIMD DMA work.
>> > This patch adds the required framework to exynos_fimd driver,
>> > and disables FIMD sysmmu on Exynos5420.
>> >
>> > Signed-off-by: Ajay Kumar <ajaykumar.rs at samsung.com>
>>
>> Acked-by: Simon Glass <sjg at chromium.org>
>>
>> See a nit below if you re-issue this series.
>>
>> > ---
>> >  arch/arm/dts/exynos5420.dtsi                 |  7 +++++++
>> >  doc/device-tree-bindings/video/exynos-fb.txt |  4 ++++
>> >  drivers/video/exynos_fimd.c                  | 24
>> ++++++++++++++++++++++++
>> >  3 files changed, 35 insertions(+)
>> >
>> > diff --git a/arch/arm/dts/exynos5420.dtsi b/arch/arm/dts/exynos5420.dtsi
>> > index ca6c605..7443953 100644
>> > --- a/arch/arm/dts/exynos5420.dtsi
>> > +++ b/arch/arm/dts/exynos5420.dtsi
>> > @@ -71,4 +71,11 @@
>> >                 reg = <0x12E20000 0x100>;
>> >                 interrupts = <0 203 0>;
>> >         };
>> > +
>> > +       fimd at 14400000 {
>> > +               /* sysmmu is not used in U-Boot */
>> > +               samsung,disable-sysmmu;
>> > +               samsung,sysmmu-fimdm0 = <0x14640000>;
>> > +               samsung,sysmmu-fimdm1 = <0x14680000>;
>> > +       };
>> >  };
>> > diff --git a/doc/device-tree-bindings/video/exynos-fb.txt
>> b/doc/device-tree-bindings/video/exynos-fb.txt
>> > index bb7441c..9ba2c47 100644
>> > --- a/doc/device-tree-bindings/video/exynos-fb.txt
>> > +++ b/doc/device-tree-bindings/video/exynos-fb.txt
>> > @@ -55,6 +55,10 @@ Board(panel specific):
>> >         samsung,pclk-name: parent clock identifier: 1(MPLL), 2(EPLL),
>> 3(VPLL)
>> >         samsung,sclk-div: parent_clock/source_clock ratio
>> >         samsung,dual-lcd-enabled: 1 if you support two LCD, else 0
>> > +       samsung,disable-sysmmu: present if you want to disable the
>> sysmmu
>> > +                       (needed for Exynos5420 and newer versions)
>> > +       samsung,sysmmu-fimdm0: Address of sysmmufimdm0 MMU_CTRL
>> > +       samsung,sysmmu-fimdm1: Address of sysmmufimdm1 MMU_CTRL
>>
>> Is this a kernel binding?
>>
>> No. In kernel, we have DT nodes for FIMD symmus as well.
> How about creating FIMD sysmmu nodes in u-boot as well and use them inside
> exynos_fimd.c, rather than giving the sysmmu base addresses as a FIMD DT
> property?
>
>> >
>> >  Example:
>> >  SOC specific part:
>> > diff --git a/drivers/video/exynos_fimd.c b/drivers/video/exynos_fimd.c
>> > index f962c4f..bffc8fa 100644
>> > --- a/drivers/video/exynos_fimd.c
>> > +++ b/drivers/video/exynos_fimd.c
>> > @@ -257,6 +257,7 @@ void exynos_fimd_lcd_init(vidinfo_t *vid)
>> >         unsigned int offset;
>> >  #ifdef CONFIG_OF_CONTROL
>> >         unsigned int node;
>> > +       u32 *sysmmufimdm0, *sysmmufimdm1;
>> >
>> >         node = fdtdec_next_compatible(gd->fdt_blob,
>> >                                         0, COMPAT_SAMSUNG_EXYNOS_FIMD);
>> > @@ -267,6 +268,29 @@ void exynos_fimd_lcd_init(vidinfo_t *vid)
>> >                                                                 node,
>> "reg");
>> >         if (fimd_ctrl == NULL)
>> >                 debug("Can't get the FIMD base address\n");
>> > +
>> > +       if (fdtdec_get_bool(gd->fdt_blob, node,
>> "samsung,disable-sysmmu")) {
>> > +               /*
>> > +               * The reset value for FIMD SYSMMU register MMU_CTRL is 3
>> > +               * on Exynos5420 and newer versions.
>> > +               * This means FIMD SYSMMU is on by default on Exynos5420
>> > +               * and newer versions.
>> > +               * Since in u-boot we don't use SYSMMU, we should disable
>> > +               * those FIMD SYSMMU.
>> > +               */
>> > +               sysmmufimdm0 = (u32 *)fdtdec_get_int(gd->fdt_blob, node,
>> > +
>> "samsung,sysmmu-fimdm0", 0);
>>
>> fdtdec_get_addr() might be better.
>
>
>> > +               if (!sysmmufimdm0)
>> > +                       debug("Can't get sysmmufimdm0");
>> > +
>> > +               sysmmufimdm1 = (u32 *)fdtdec_get_int(gd->fdt_blob, node,
>> > +
>> "samsung,sysmmu-fimdm1", 0);
>> > +               if (!sysmmufimdm1)
>> > +                       debug("Can't get sysmmufimdm1");
>> > +
>> > +               writel(0x0, sysmmufimdm0);
>> > +               writel(0x0, sysmmufimdm1);
>> > +       }
>> >  #else
>> >         fimd_ctrl = (struct exynos_fb *)samsung_get_base_fimd();
>> >  #endif
>> > --
>> > 1.7.12.4
>> >
>>
>> Regards,
>> Simon
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>>
>
>
> Thanks and Regards,
> Ajay
>
>