When copying RSA use io memcpy functions if the destination address
contains a GPU local memory address. Considering even the source
address can be on local memory, a bounce buffer is used to copy from io
to io.
The intention of this patch is to make i915 portable outside x86 mainly
on ARM64.
Signed-off-by: Balasubramani Vivekanandan <balasubramani.vivekanandan@xxxxxxxxx>
---
drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c | 23 +++++++++++++++++++++--
1 file changed, 21 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c b/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c
index bb864655c495..06d30670e15c 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c
@@ -589,7 +589,7 @@ static int uc_fw_rsa_data_create(struct intel_uc_fw *uc_fw)
struct intel_gt *gt = __uc_fw_to_gt(uc_fw);
struct i915_vma *vma;
size_t copied;
- void *vaddr;
+ void *vaddr, *bounce;
int err;
err = i915_inject_probe_error(gt->i915, -ENXIO);
@@ -621,7 +621,26 @@ static int uc_fw_rsa_data_create(struct intel_uc_fw *uc_fw)
goto unpin_out;
}
- copied = intel_uc_fw_copy_rsa(uc_fw, vaddr, vma->size);
+ if (i915_gem_object_is_lmem(vma->obj)) {
+ /* When vma is allocated from the GPU local memmory, it means
+ * the destination address contains an io memory and we need to
+ * use memcpy function for io memory for copying, to ensure
+ * i915 portability outside x86. It is most likely the RSA will
+ * also be on local memory and so the source of copy will also
+ * be an io address. Since we cannot directly copy from io to
+ * io, we use a bounce buffer to copy.
+ */
+ copied = 0;
+ bounce = kmalloc(vma->size, GFP_KERNEL);
+ if (likely(bounce)) {
+ copied = intel_uc_fw_copy_rsa(uc_fw, bounce, vma->size);
+ memcpy_toio((void __iomem *)vaddr, bounce, copied);
+ kfree(bounce);
+ }
+ } else {
+ copied = intel_uc_fw_copy_rsa(uc_fw, vaddr, vma->size);
+ }
+
i915_gem_object_unpin_map(vma->obj);
if (copied < uc_fw->rsa_size) {
--
2.25.1
