From f203e0f5d119a7ebab00cbf837876cc475830ae6 Mon Sep 17 00:00:00 2001 From: Tom St Denis Date: Tue, 29 Aug 2017 08:36:52 -0400 Subject: [PATCH 0878/4131] drm/amd/amdgpu: Add write() method to VRAM debugfs entry (v2) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Allows writing data to vram via debugfs. Signed-off-by: Tom St Denis Reviewed-by: Christian König (v2): Call get_user before holding spinlock. Signed-off-by: Alex Deucher --- 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 d2431cc..bbe7d2b 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c @@ -1914,10 +1914,50 @@ 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 -- 2.7.4