lkml.org 
[lkml]   [2019]   [Dec]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [PATCH] ARM: dts: bcm2711: fix soc's node dma-ranges
Date
On Wed,  4 Dec 2019 13:56:33 +0100, Nicolas Saenz Julienne <nsaenzjulienne@suse.de> wrote:
> Raspberry Pi's firmware has a feature to select how much memory to
> reserve for its GPU called 'gpu_mem'. The possible values go from 16MB
> to 944MB, with a default of 64MB. This memory resides in the topmost
> part of the lower 1GB memory area and grows bigger expanding towards the
> begging of memory.
>
> It turns out that with low 'gpu_mem' values (16MB and 32MB) the size of
> the memory available to the system in the lower 1GB area can outgrow the
> interconnect's dma-range as its size was selected based on the maximum
> system memory available given the default gpu_mem configuration. This
> makes that memory slice unavailable for DMA. And may cause nasty kernel
> warnings if CMA happens to include it.
>
> Change soc's dma-ranges to really reflect it's HW limitation, which is
> being able to only DMA to the lower 1GB area.
>
> Fixes: 7dbe8c62ceeb ("ARM: dts: Add minimal Raspberry Pi 4 support")
> Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
> ---

Applied to devicetree/fixes, thanks!
--
Florian

\
 
 \ /
  Last update: 2019-12-09 19:13    [W:0.054 / U:19.356 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site