From 8a08e50cee669387195a1189ec9aee42edc1da49 Mon Sep 17 00:00:00 2001 From: Serge Semin Date: Tue, 23 Apr 2019 15:31:22 +0300 Subject: drm: Permit video-buffers writecombine mapping for MIPS MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Since commit 4b050ba7a66c ("MIPS: pgtable.h: Implement the pgprot_writecombine function for MIPS") and commit c4687b15a848 ("MIPS: Fix definition of pgprot_writecombine()") write-combine vma mapping is available to be used by kernel subsystems for MIPS. In particular the uncached accelerated attribute is requested to be set by ioremap_wc() method and by generic PCI memory pages/ranges mapping methods. The same is done by the drm_io_prot()/ttm_io_prot() functions in case if write-combine flag is set for vma's passed for mapping. But for some reason the pgprot_writecombine() method calling is ifdefed to be a platform-specific with MIPS system being marked as lacking of one. At the very least it doesn't reflect the current MIPS platform implementation. So in order to improve the DRM subsystem performance on MIPS with UCA mapping enabled, we need to have pgprot_writecombine() called for buffers, which need store operations being combined. In case if particular MIPS chip doesn't support the UCA attribute, the mapping will fall back to noncached. Cc: Ralf Baechle Cc: Paul Burton Cc: James Hogan Acked-by: Christian König Reviewed-by: Paul Burton Signed-off-by: Vadim V. Vlasov Signed-off-by: Serge Semin Signed-off-by: Sean Paul Link: https://patchwork.freedesktop.org/patch/msgid/20190423123122.32573-1-fancer.lancer@gmail.com --- drivers/gpu/drm/drm_vm.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'drivers/gpu/drm/drm_vm.c') diff --git a/drivers/gpu/drm/drm_vm.c b/drivers/gpu/drm/drm_vm.c index 2f24ee6c7a92..05f7c5833946 100644 --- a/drivers/gpu/drm/drm_vm.c +++ b/drivers/gpu/drm/drm_vm.c @@ -74,7 +74,8 @@ static pgprot_t drm_io_prot(struct drm_local_map *map, /* We don't want graphics memory to be mapped encrypted */ tmp = pgprot_decrypted(tmp); -#if defined(__i386__) || defined(__x86_64__) || defined(__powerpc__) +#if defined(__i386__) || defined(__x86_64__) || defined(__powerpc__) || \ + defined(__mips__) if (map->type == _DRM_REGISTERS && !(map->flags & _DRM_WRITE_COMBINING)) tmp = pgprot_noncached(tmp); else @@ -85,7 +86,7 @@ static pgprot_t drm_io_prot(struct drm_local_map *map, tmp = pgprot_writecombine(tmp); else tmp = pgprot_noncached(tmp); -#elif defined(__sparc__) || defined(__arm__) || defined(__mips__) +#elif defined(__sparc__) || defined(__arm__) tmp = pgprot_noncached(tmp); #endif return tmp; -- cgit v1.2.3