From 24719e94ca2a9397f1385da4bce6a7adea1868a7 Mon Sep 17 00:00:00 2001 From: Maarten Lankhorst Date: Mon, 22 Oct 2018 12:20:00 +0200 Subject: [PATCH] drm/i915: Fix unsigned overflow when calculating total data rate, v2. MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit On gen11, we can definitely smash the 32-bits barrier with just a when we enable all planes in the next patch. Changes since v1: - Use div64_u64 (ickle). Signed-off-by: Maarten Lankhorst Reviewed-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20181022102000.30255-1-maarten.lankhorst@linux.intel.com --- drivers/gpu/drm/i915/intel_pm.c | 47 +++++++++++++++++++---------------------- 1 file changed, 22 insertions(+), 25 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 67a4d07..f42b8c3 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -3784,7 +3784,7 @@ bool intel_can_enable_sagv(struct drm_atomic_state *state) static u16 intel_get_ddb_size(struct drm_i915_private *dev_priv, const struct intel_crtc_state *cstate, - const unsigned int total_data_rate, + const u64 total_data_rate, const int num_active, struct skl_ddb_allocation *ddb) { @@ -3798,12 +3798,12 @@ static u16 intel_get_ddb_size(struct drm_i915_private *dev_priv, return ddb_size - 4; /* 4 blocks for bypass path allocation */ adjusted_mode = &cstate->base.adjusted_mode; - total_data_bw = (u64)total_data_rate * drm_mode_vrefresh(adjusted_mode); + total_data_bw = total_data_rate * drm_mode_vrefresh(adjusted_mode); /* * 12GB/s is maximum BW supported by single DBuf slice. */ - if (total_data_bw >= GBps(12) || num_active > 1) { + if (num_active > 1 || total_data_bw >= GBps(12)) { ddb->enabled_slices = 2; } else { ddb->enabled_slices = 1; @@ -3816,7 +3816,7 @@ static u16 intel_get_ddb_size(struct drm_i915_private *dev_priv, static void skl_ddb_get_pipe_allocation_limits(struct drm_device *dev, const struct intel_crtc_state *cstate, - const unsigned int total_data_rate, + const u64 total_data_rate, struct skl_ddb_allocation *ddb, struct skl_ddb_entry *alloc, /* out */ int *num_active /* out */) @@ -4139,7 +4139,7 @@ int skl_check_pipe_max_pixel_rate(struct intel_crtc *intel_crtc, return 0; } -static unsigned int +static u64 skl_plane_relative_data_rate(const struct intel_crtc_state *cstate, const struct drm_plane_state *pstate, const int plane) @@ -4151,6 +4151,7 @@ skl_plane_relative_data_rate(const struct intel_crtc_state *cstate, struct drm_framebuffer *fb; u32 format; uint_fixed_16_16_t down_scale_amount; + u64 rate; if (!intel_pstate->base.visible) return 0; @@ -4177,28 +4178,26 @@ skl_plane_relative_data_rate(const struct intel_crtc_state *cstate, height /= 2; } - data_rate = width * height * fb->format->cpp[plane]; + data_rate = width * height; down_scale_amount = skl_plane_downscale_amount(cstate, intel_pstate); - return mul_round_up_u32_fixed16(data_rate, down_scale_amount); + rate = mul_round_up_u32_fixed16(data_rate, down_scale_amount); + + rate *= fb->format->cpp[plane]; + return rate; } -/* - * We don't overflow 32 bits. Worst case is 3 planes enabled, each fetching - * a 8192x4096@32bpp framebuffer: - * 3 * 4096 * 8192 * 4 < 2^32 - */ -static unsigned int +static u64 skl_get_total_relative_data_rate(struct intel_crtc_state *intel_cstate, - unsigned int *plane_data_rate, - unsigned int *uv_plane_data_rate) + u64 *plane_data_rate, + u64 *uv_plane_data_rate) { struct drm_crtc_state *cstate = &intel_cstate->base; struct drm_atomic_state *state = cstate->state; struct drm_plane *plane; const struct drm_plane_state *pstate; - unsigned int total_data_rate = 0; + u64 total_data_rate = 0; if (WARN_ON(!state)) return 0; @@ -4206,7 +4205,7 @@ skl_get_total_relative_data_rate(struct intel_crtc_state *intel_cstate, /* Calculate and cache data rate for each plane */ drm_atomic_crtc_state_for_each_plane_state(plane, pstate, cstate) { enum plane_id plane_id = to_intel_plane(plane)->id; - unsigned int rate; + u64 rate; /* packed/y */ rate = skl_plane_relative_data_rate(intel_cstate, @@ -4325,11 +4324,11 @@ skl_allocate_pipe_ddb(struct intel_crtc_state *cstate, uint16_t alloc_size, start; uint16_t minimum[I915_MAX_PLANES] = {}; uint16_t uv_minimum[I915_MAX_PLANES] = {}; - unsigned int total_data_rate; + u64 total_data_rate; enum plane_id plane_id; int num_active; - unsigned int plane_data_rate[I915_MAX_PLANES] = {}; - unsigned int uv_plane_data_rate[I915_MAX_PLANES] = {}; + u64 plane_data_rate[I915_MAX_PLANES] = {}; + u64 uv_plane_data_rate[I915_MAX_PLANES] = {}; uint16_t total_min_blocks = 0; /* Clear the partitioning for disabled planes. */ @@ -4388,7 +4387,7 @@ skl_allocate_pipe_ddb(struct intel_crtc_state *cstate, start = alloc->start; for_each_plane_id_on_crtc(intel_crtc, plane_id) { - unsigned int data_rate, uv_data_rate; + u64 data_rate, uv_data_rate; uint16_t plane_blocks, uv_plane_blocks; if (plane_id == PLANE_CURSOR) @@ -4402,8 +4401,7 @@ skl_allocate_pipe_ddb(struct intel_crtc_state *cstate, * result is < available as data_rate / total_data_rate < 1 */ plane_blocks = minimum[plane_id]; - plane_blocks += div_u64((uint64_t)alloc_size * data_rate, - total_data_rate); + plane_blocks += div64_u64(alloc_size * data_rate, total_data_rate); /* Leave disabled planes at (0,0) */ if (data_rate) { @@ -4417,8 +4415,7 @@ skl_allocate_pipe_ddb(struct intel_crtc_state *cstate, uv_data_rate = uv_plane_data_rate[plane_id]; uv_plane_blocks = uv_minimum[plane_id]; - uv_plane_blocks += div_u64((uint64_t)alloc_size * uv_data_rate, - total_data_rate); + uv_plane_blocks += div64_u64(alloc_size * uv_data_rate, total_data_rate); if (uv_data_rate) { ddb->uv_plane[pipe][plane_id].start = start; -- 2.7.4