[Nouveau] [PATCH 2/2] bus: remove cpu_coherent flag

[Alexandre Courbot]

This flag's only remaining function is to ignore the uncached flag for
BOs on coherent architectures.

However the reason for allocating an object uncache on a non-coherent
architecture (namely because the cost of doing explicit flushes/
invalidations is higher than the benefit of caching the data because
accesses are few and far between) should also apply on architectures for
which coherency is maintained implicitly. Thus allocate coherent objects
as uncached on all architectures.

Signed-off-by: Alexandre Courbot <acourbot at nvidia.com>
---
 drm/nouveau/include/nvkm/core/device.h | 1 -
 drm/nouveau/nouveau_bo.c               | 3 +--
 drm/nouveau/nvkm/engine/device/pci.c   | 1 -
 drm/nouveau/nvkm/engine/device/tegra.c | 1 -
 lib/include/nvif/os.h                  | 6 ------
 5 files changed, 1 insertion(+), 11 deletions(-)

diff --git a/drm/nouveau/include/nvkm/core/device.h b/drm/nouveau/include/nvkm/core/device.h
index 6bc712f..7ea8aa7 100644
--- a/drm/nouveau/include/nvkm/core/device.h
+++ b/drm/nouveau/include/nvkm/core/device.h
@@ -175,7 +175,6 @@ struct nvkm_device_func {
 	void (*fini)(struct nvkm_device *, bool suspend);
 	resource_size_t (*resource_addr)(struct nvkm_device *, unsigned bar);
 	resource_size_t (*resource_size)(struct nvkm_device *, unsigned bar);
-	bool cpu_coherent;
 };
 
 struct nvkm_device_quirk {
diff --git a/drm/nouveau/nouveau_bo.c b/drm/nouveau/nouveau_bo.c
index 7115927..fbb6036 100644
--- a/drm/nouveau/nouveau_bo.c
+++ b/drm/nouveau/nouveau_bo.c
@@ -209,8 +209,7 @@ nouveau_bo_new(struct drm_device *dev, int size, int align,
 	nvbo->tile_flags = tile_flags;
 	nvbo->bo.bdev = &drm->ttm.bdev;
 
-	if (!nvxx_device(&drm->device)->func->cpu_coherent)
-		nvbo->force_coherent = flags & TTM_PL_FLAG_UNCACHED;
+	nvbo->force_coherent = flags & TTM_PL_FLAG_UNCACHED;
 
 	nvbo->page_shift = 12;
 	if (drm->client.vm) {
diff --git a/drm/nouveau/nvkm/engine/device/pci.c b/drm/nouveau/nvkm/engine/device/pci.c
index 62ad030..b1b6932 100644
--- a/drm/nouveau/nvkm/engine/device/pci.c
+++ b/drm/nouveau/nvkm/engine/device/pci.c
@@ -1614,7 +1614,6 @@ nvkm_device_pci_func = {
 	.fini = nvkm_device_pci_fini,
 	.resource_addr = nvkm_device_pci_resource_addr,
 	.resource_size = nvkm_device_pci_resource_size,
-	.cpu_coherent = !IS_ENABLED(CONFIG_ARM),
 };
 
 int
diff --git a/drm/nouveau/nvkm/engine/device/tegra.c b/drm/nouveau/nvkm/engine/device/tegra.c
index 9b638bd..939682f 100644
--- a/drm/nouveau/nvkm/engine/device/tegra.c
+++ b/drm/nouveau/nvkm/engine/device/tegra.c
@@ -245,7 +245,6 @@ nvkm_device_tegra_func = {
 	.fini = nvkm_device_tegra_fini,
 	.resource_addr = nvkm_device_tegra_resource_addr,
 	.resource_size = nvkm_device_tegra_resource_size,
-	.cpu_coherent = false,
 };
 
 int
diff --git a/lib/include/nvif/os.h b/lib/include/nvif/os.h
index c265ab4..c13db8d 100644
--- a/lib/include/nvif/os.h
+++ b/lib/include/nvif/os.h
@@ -124,12 +124,6 @@ typedef dma_addr_t resource_size_t;
 #define __printf(a,b)
 #define __user
 
-#if defined(CONFIG_ARM)
-#define IS_ENABLED_CONFIG_ARM 1
-#else
-#define IS_ENABLED_CONFIG_ARM 0
-#endif
-
 #if defined(CONFIG_IOMMU_API)
 #define IS_ENABLED_CONFIG_IOMMU_API 1
 #else
-- 
2.9.0