[ +arm64 maintainers for their awareness, which would have been a good
thing to do from the start ]
On 2022-02-25 03:24, Michael Cheng wrote:
Add arm64 support for drm_clflush_virt_range. caches_clean_inval_pou
performs a flush by first performing a clean, follow by an invalidation
operation.
v2 (Michael Cheng): Use correct macro for cleaning and invalidation the
dcache. Thanks Tvrtko for the suggestion.
v3 (Michael Cheng): Replace asm/cacheflush.h with linux/cacheflush.h
v4 (Michael Cheng): Arm64 does not export dcache_clean_inval_poc as a
symbol that could be use by other modules, thus use
caches_clean_inval_pou instead. Also this version
removes include for cacheflush, since its already
included base on architecture type.
Signed-off-by: Michael Cheng <michael.cheng@xxxxxxxxx>
Reviewed-by: Matt Roper <matthew.d.roper@xxxxxxxxx>
---
drivers/gpu/drm/drm_cache.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/drivers/gpu/drm/drm_cache.c b/drivers/gpu/drm/drm_cache.c
index c3e6e615bf09..81c28714f930 100644
--- a/drivers/gpu/drm/drm_cache.c
+++ b/drivers/gpu/drm/drm_cache.c
@@ -174,6 +174,11 @@ drm_clflush_virt_range(void *addr, unsigned long length)
if (wbinvd_on_all_cpus())
pr_err("Timed out waiting for cache flush\n");
+
+#elif defined(CONFIG_ARM64)
+ void *end = addr + length;
+ caches_clean_inval_pou((unsigned long)addr, (unsigned long)end);
Why does i915 need to ensure the CPU's instruction cache is coherent
with its data cache? Is it a self-modifying driver?
Robin.
(Note that the above is somewhat of a loaded question, and I do actually
have half an idea of what you're trying to do here and why it won't fly,
but I'd like to at least assume you've read the documentation of the
function you decided was OK to use)
+
#else
WARN_ONCE(1, "Architecture has no drm_cache.c support\n");
#endif
