| Message ID | 20200423234903.226369-1-pcc@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | arm64: dts: fast models: Switch to dynamically allocated VRAM | expand |
On Thu, Apr 23, 2020 at 04:49:03PM -0700, Peter Collingbourne wrote: > According to the Fast Models Reference Manual, FVP has 32MB of video > RAM, However, even 32MB is not sufficient for some applications, > such as Android, which requires around 100-200MB when textures are > allocated in VRAM via DRM. > > FVP supports DMA between DRAM and the graphics device. Therefore, > use a dynamically allocated region of reserved memory to provide > a sufficient amount of video RAM. The allocation is of size 256MB, > which ought to be enough for anyone. > > Although this means that the designated VRAM ends up being left unused, > FVP allows the size of DRAM to be configurable, so this should not > be a problem in practice. > > Signed-off-by: Peter Collingbourne <pcc@google.com> > --- > arch/arm64/boot/dts/arm/fvp-base-revc.dts | 6 ++---- > 1 file changed, 2 insertions(+), 4 deletions(-) > > diff --git a/arch/arm64/boot/dts/arm/fvp-base-revc.dts b/arch/arm64/boot/dts/arm/fvp-base-revc.dts > index 66381d89c1ce..57641f16f22e 100644 > --- a/arch/arm64/boot/dts/arm/fvp-base-revc.dts > +++ b/arch/arm64/boot/dts/arm/fvp-base-revc.dts > @@ -103,11 +103,9 @@ reserved-memory { > #size-cells = <2>; > ranges; > > - /* Chipselect 2,00000000 is physically at 0x18000000 */ > - vram: vram@18000000 { > - /* 8 MB of designated video RAM */ > + vram: vram { > compatible = "shared-dma-pool"; > - reg = <0x00000000 0x18000000 0 0x00800000>; I am not sure if it is valid to just specify the size without the reg field. The reverse is valid IIUC. Moreover I assume the idea is to populate the reg field based on the model parameters ? If so, who can't the reg and size field be modified instead of deleting here and adding it elsewhere. -- Regards, Sudeep
diff --git a/arch/arm64/boot/dts/arm/fvp-base-revc.dts b/arch/arm64/boot/dts/arm/fvp-base-revc.dts index 66381d89c1ce..57641f16f22e 100644 --- a/arch/arm64/boot/dts/arm/fvp-base-revc.dts +++ b/arch/arm64/boot/dts/arm/fvp-base-revc.dts @@ -103,11 +103,9 @@ reserved-memory { #size-cells = <2>; ranges; - /* Chipselect 2,00000000 is physically at 0x18000000 */ - vram: vram@18000000 { - /* 8 MB of designated video RAM */ + vram: vram { compatible = "shared-dma-pool"; - reg = <0x00000000 0x18000000 0 0x00800000>; + size = <0 0x10000000>; no-map; }; };
According to the Fast Models Reference Manual, FVP has 32MB of video RAM, However, even 32MB is not sufficient for some applications, such as Android, which requires around 100-200MB when textures are allocated in VRAM via DRM. FVP supports DMA between DRAM and the graphics device. Therefore, use a dynamically allocated region of reserved memory to provide a sufficient amount of video RAM. The allocation is of size 256MB, which ought to be enough for anyone. Although this means that the designated VRAM ends up being left unused, FVP allows the size of DRAM to be configurable, so this should not be a problem in practice. Signed-off-by: Peter Collingbourne <pcc@google.com> --- arch/arm64/boot/dts/arm/fvp-base-revc.dts | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-)