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 <mario.kleiner.de at gmail.com> Reported-by: Ben Hutchings <ben.hutchings at codethink.co.uk> Fixes: d63c277dc672 ("drm/amdgpu: Make display watermark calculations more accurate") Cc: Ben Hutchings <ben.hutchings at codethink.co.uk> Cc: Alex Deucher <alexander.deucher at amd.com> Cc: stable at vger.kernel.org --- 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 3c62c45..9f78c03 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 c8ed0fa..4bcf01d 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 3f3a254..eaa8f90 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 3e90c19..a9e8695 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) { -- 2.7.4