| Message ID | 20240515121358.2027178-1-l.stach@pengutronix.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/etnaviv: don't disable TS on MMUv2 core when moving the linear window | expand |
Hi Lucas, On Wed, May 15, 2024 at 02:13:58PM +0200, Lucas Stach wrote: > On MMUv2 cores the linear window is only relevant when starting the FE, > before the MMU has been activated. Once the MMU is active, all accesses > are translated with no way to bypass the MMU via the linear window. Thus > TS ignoring the linear window offset is not an issue on cores with MMUv2 > present and there is no need to disable TS when we need to move the > linear window. > > Signed-off-by: Lucas Stach <l.stach@pengutronix.de> Tested-by: Joao Paulo Goncalves <joao.goncalves@toradex.com> Thanks for the patch! What do you think in backporting the patch to stable and adding a "Fixes:" tag? Regards, João Paulo
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c index 2db0fb071a57..50a6dc005bf8 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.c @@ -875,12 +875,15 @@ int etnaviv_gpu_init(struct etnaviv_gpu *gpu) * * On MC1.0 cores the linear window offset is ignored by the TS engine, * leading to inconsistent memory views. Avoid using the offset on those - * cores if possible, otherwise disable the TS feature. + * cores if possible, otherwise disable the TS feature. MMUv2 doesn't + * expose this issue, as all TS accesses are MMU translated, so the + * linear window offset won't be used. */ cmdbuf_paddr = ALIGN_DOWN(etnaviv_cmdbuf_get_pa(&gpu->buffer), SZ_128M); if (!(gpu->identity.features & chipFeatures_PIPE_3D) || - (gpu->identity.minor_features0 & chipMinorFeatures0_MC20)) { + (gpu->identity.minor_features0 & chipMinorFeatures0_MC20) || + (gpu->identity.minor_features1 & chipMinorFeatures1_MMU_VERSION)) { if (cmdbuf_paddr >= SZ_2G) priv->mmu_global->memory_base = SZ_2G; else
On MMUv2 cores the linear window is only relevant when starting the FE, before the MMU has been activated. Once the MMU is active, all accesses are translated with no way to bypass the MMU via the linear window. Thus TS ignoring the linear window offset is not an issue on cores with MMUv2 present and there is no need to disable TS when we need to move the linear window. Signed-off-by: Lucas Stach <l.stach@pengutronix.de> --- drivers/gpu/drm/etnaviv/etnaviv_gpu.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)