Allows writing data to vram via debugfs.
Signed-off-by: Tom St Denis <tom.stdenis at amd.com>
(v2): Call get_user before holding spinlock.
---
drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 42 ++++++++++++++++++++++++++++++++-
1 file changed, 41 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index c97a99427eea..e9a05186b889 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
@@ -1671,10 +1671,50 @@ static ssize_t amdgpu_ttm_vram_read(struct file *f, char __user *buf,
return result;
}
+static ssize_t amdgpu_ttm_vram_write(struct file *f, const char __user *buf,
+ size_t size, loff_t *pos)
+{
+ struct amdgpu_device *adev = file_inode(f)->i_private;
+ ssize_t result = 0;
+ int r;
+
+ if (size & 0x3 || *pos & 0x3)
+ return -EINVAL;
+
+ if (*pos >= adev->mc.mc_vram_size)
+ return -ENXIO;
+
+ while (size) {
+ unsigned long flags;
+ uint32_t value;
+
+ if (*pos >= adev->mc.mc_vram_size)
+ return result;
+
+ r = get_user(value, (uint32_t *)buf);
+ if (r)
+ return r;
+
+ spin_lock_irqsave(&adev->mmio_idx_lock, flags);
+ WREG32(mmMM_INDEX, ((uint32_t)*pos) | 0x80000000);
+ WREG32(mmMM_INDEX_HI, *pos >> 31);
+ WREG32(mmMM_DATA, value);
+ spin_unlock_irqrestore(&adev->mmio_idx_lock, flags);
+
+ result += 4;
+ buf += 4;
+ *pos += 4;
+ size -= 4;
+ }
+
+ return result;
+}
+
static const struct file_operations amdgpu_ttm_vram_fops = {
.owner = THIS_MODULE,
.read = amdgpu_ttm_vram_read,
- .llseek = default_llseek
+ .write = amdgpu_ttm_vram_write,
+ .llseek = default_llseek,
};
#ifdef CONFIG_DRM_AMDGPU_GART_DEBUGFS
--
2.12.0
