From bea10413934dcf98cb9b2dfcdc56e1d28f192897 Mon Sep 17 00:00:00 2001 From: Mario Kleiner Date: Tue, 13 Jun 2017 07:17:10 +0200 Subject: [PATCH] drm/amdgpu: Fix overflow of watermark calcs at > 4k resolutions. Commit d63c277dc672e0 ("drm/amdgpu: Make display watermark calculations more accurate") made watermark calculations more accurate, but not for > 4k resolutions on 32-Bit architectures, as it introduced an integer overflow for those setups and resolutions. Fix this by proper u64 casting and division. Signed-off-by: Mario Kleiner Reported-by: Ben Hutchings Fixes: d63c277dc672 ("drm/amdgpu: Make display watermark calculations more accurate") Cc: Ben Hutchings Cc: Alex Deucher Cc: stable@vger.kernel.org Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/amdgpu/dce_v10_0.c | 7 +++++-- drivers/gpu/drm/amd/amdgpu/dce_v11_0.c | 7 +++++-- drivers/gpu/drm/amd/amdgpu/dce_v6_0.c | 7 +++++-- drivers/gpu/drm/amd/amdgpu/dce_v8_0.c | 7 +++++-- 4 files changed, 20 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/amd/amdgpu/dce_v10_0.c b/drivers/gpu/drm/amd/amdgpu/dce_v10_0.c index 0cdeb6a2e4a0..5dffa27afa45 100644 --- a/drivers/gpu/drm/amd/amdgpu/dce_v10_0.c +++ b/drivers/gpu/drm/amd/amdgpu/dce_v10_0.c @@ -1207,8 +1207,11 @@ static void dce_v10_0_program_watermarks(struct amdgpu_device *adev, u32 tmp, wm_mask, lb_vblank_lead_lines = 0; if (amdgpu_crtc->base.enabled && num_heads && mode) { - active_time = 1000000UL * (u32)mode->crtc_hdisplay / (u32)mode->clock; - line_time = min((u32) (1000000UL * (u32)mode->crtc_htotal / (u32)mode->clock), (u32)65535); + active_time = (u32) div_u64((u64)mode->crtc_hdisplay * 1000000, + (u32)mode->clock); + line_time = (u32) div_u64((u64)mode->crtc_htotal * 1000000, + (u32)mode->clock); + line_time = min(line_time, (u32)65535); /* watermark for high clocks */ if (adev->pm.dpm_enabled) { diff --git a/drivers/gpu/drm/amd/amdgpu/dce_v11_0.c b/drivers/gpu/drm/amd/amdgpu/dce_v11_0.c index 773654a19749..47bbc87f96d2 100644 --- a/drivers/gpu/drm/amd/amdgpu/dce_v11_0.c +++ b/drivers/gpu/drm/amd/amdgpu/dce_v11_0.c @@ -1176,8 +1176,11 @@ static void dce_v11_0_program_watermarks(struct amdgpu_device *adev, u32 tmp, wm_mask, lb_vblank_lead_lines = 0; if (amdgpu_crtc->base.enabled && num_heads && mode) { - active_time = 1000000UL * (u32)mode->crtc_hdisplay / (u32)mode->clock; - line_time = min((u32) (1000000UL * (u32)mode->crtc_htotal / (u32)mode->clock), (u32)65535); + active_time = (u32) div_u64((u64)mode->crtc_hdisplay * 1000000, + (u32)mode->clock); + line_time = (u32) div_u64((u64)mode->crtc_htotal * 1000000, + (u32)mode->clock); + line_time = min(line_time, (u32)65535); /* watermark for high clocks */ if (adev->pm.dpm_enabled) { diff --git a/drivers/gpu/drm/amd/amdgpu/dce_v6_0.c b/drivers/gpu/drm/amd/amdgpu/dce_v6_0.c index 1f3552967ba3..d8c9a959493e 100644 --- a/drivers/gpu/drm/amd/amdgpu/dce_v6_0.c +++ b/drivers/gpu/drm/amd/amdgpu/dce_v6_0.c @@ -983,8 +983,11 @@ static void dce_v6_0_program_watermarks(struct amdgpu_device *adev, fixed20_12 a, b, c; if (amdgpu_crtc->base.enabled && num_heads && mode) { - active_time = 1000000UL * (u32)mode->crtc_hdisplay / (u32)mode->clock; - line_time = min((u32) (1000000UL * (u32)mode->crtc_htotal / (u32)mode->clock), (u32)65535); + active_time = (u32) div_u64((u64)mode->crtc_hdisplay * 1000000, + (u32)mode->clock); + line_time = (u32) div_u64((u64)mode->crtc_htotal * 1000000, + (u32)mode->clock); + line_time = min(line_time, (u32)65535); priority_a_cnt = 0; priority_b_cnt = 0; diff --git a/drivers/gpu/drm/amd/amdgpu/dce_v8_0.c b/drivers/gpu/drm/amd/amdgpu/dce_v8_0.c index 3c558c170e5e..db30c6ba563a 100644 --- a/drivers/gpu/drm/amd/amdgpu/dce_v8_0.c +++ b/drivers/gpu/drm/amd/amdgpu/dce_v8_0.c @@ -1091,8 +1091,11 @@ static void dce_v8_0_program_watermarks(struct amdgpu_device *adev, u32 tmp, wm_mask, lb_vblank_lead_lines = 0; if (amdgpu_crtc->base.enabled && num_heads && mode) { - active_time = 1000000UL * (u32)mode->crtc_hdisplay / (u32)mode->clock; - line_time = min((u32) (1000000UL * (u32)mode->crtc_htotal / (u32)mode->clock), (u32)65535); + active_time = (u32) div_u64((u64)mode->crtc_hdisplay * 1000000, + (u32)mode->clock); + line_time = (u32) div_u64((u64)mode->crtc_htotal * 1000000, + (u32)mode->clock); + line_time = min(line_time, (u32)65535); /* watermark for high clocks */ if (adev->pm.dpm_enabled) { -- 2.39.5