From dc8184aa8621ee8048652496884d9f40d4bb407f Mon Sep 17 00:00:00 2001 From: Rex Zhu Date: Mon, 10 Oct 2016 15:57:21 +0800 Subject: drm/amdgpu: change vblank_time's calculation method to reduce computational error. Signed-off-by: Rex Zhu Reviewed-by: Alex Deucher Signed-off-by: Alex Deucher Cc: stable@vger.kernel.org --- drivers/gpu/drm/amd/amdgpu/amdgpu_dpm.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) (limited to 'drivers/gpu') diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_dpm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_dpm.c index fe36caf1b7d7..14f57d9915e3 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_dpm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_dpm.c @@ -113,24 +113,26 @@ void amdgpu_dpm_print_ps_status(struct amdgpu_device *adev, printk("\n"); } + u32 amdgpu_dpm_get_vblank_time(struct amdgpu_device *adev) { struct drm_device *dev = adev->ddev; struct drm_crtc *crtc; struct amdgpu_crtc *amdgpu_crtc; - u32 line_time_us, vblank_lines; + u32 vblank_in_pixels; u32 vblank_time_us = 0xffffffff; /* if the displays are off, vblank time is max */ if (adev->mode_info.num_crtc && adev->mode_info.mode_config_initialized) { list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) { amdgpu_crtc = to_amdgpu_crtc(crtc); if (crtc->enabled && amdgpu_crtc->enabled && amdgpu_crtc->hw_mode.clock) { - line_time_us = (amdgpu_crtc->hw_mode.crtc_htotal * 1000) / - amdgpu_crtc->hw_mode.clock; - vblank_lines = amdgpu_crtc->hw_mode.crtc_vblank_end - + vblank_in_pixels = + amdgpu_crtc->hw_mode.crtc_htotal * + (amdgpu_crtc->hw_mode.crtc_vblank_end - amdgpu_crtc->hw_mode.crtc_vdisplay + - (amdgpu_crtc->v_border * 2); - vblank_time_us = vblank_lines * line_time_us; + (amdgpu_crtc->v_border * 2)); + + vblank_time_us = vblank_in_pixels * 1000 / amdgpu_crtc->hw_mode.clock; break; } } -- cgit v1.2.1