From 37126462a4feadeb3ff08c4b308a28e4db8c83a7 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrjala@linux.intel.com> Date: Thu, 1 Aug 2013 16:18:55 +0300 Subject: [PATCH] drm/i915: Add comments about units of latency values MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit All the ILK+ WM compute functions take the latency values in 0.1us units. Add a few comments to remind people about that. Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> --- drivers/gpu/drm/i915/intel_pm.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index ccaadc87b6bb..c20d68298072 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -2123,6 +2123,7 @@ static uint32_t ilk_pipe_pixel_rate(struct drm_device *dev, return pixel_rate; } +/* latency must be in 0.1us units. */ static uint32_t ilk_wm_method1(uint32_t pixel_rate, uint8_t bytes_per_pixel, uint32_t latency) { @@ -2137,6 +2138,7 @@ static uint32_t ilk_wm_method1(uint32_t pixel_rate, uint8_t bytes_per_pixel, return ret; } +/* latency must be in 0.1us units. */ static uint32_t ilk_wm_method2(uint32_t pixel_rate, uint32_t pipe_htotal, uint32_t horiz_pixels, uint8_t bytes_per_pixel, uint32_t latency) @@ -2200,7 +2202,10 @@ enum hsw_data_buf_partitioning { HSW_DATA_BUF_PART_5_6, }; -/* For both WM_PIPE and WM_LP. */ +/* + * For both WM_PIPE and WM_LP. + * mem_value must be in 0.1us units. + */ static uint32_t ilk_compute_pri_wm(struct hsw_pipe_wm_parameters *params, uint32_t mem_value, bool is_lp) @@ -2227,7 +2232,10 @@ static uint32_t ilk_compute_pri_wm(struct hsw_pipe_wm_parameters *params, return min(method1, method2); } -/* For both WM_PIPE and WM_LP. */ +/* + * For both WM_PIPE and WM_LP. + * mem_value must be in 0.1us units. + */ static uint32_t ilk_compute_spr_wm(struct hsw_pipe_wm_parameters *params, uint32_t mem_value) { @@ -2247,7 +2255,10 @@ static uint32_t ilk_compute_spr_wm(struct hsw_pipe_wm_parameters *params, return min(method1, method2); } -/* For both WM_PIPE and WM_LP. */ +/* + * For both WM_PIPE and WM_LP. + * mem_value must be in 0.1us units. + */ static uint32_t ilk_compute_cur_wm(struct hsw_pipe_wm_parameters *params, uint32_t mem_value) { -- GitLab