| Message ID | 20210125114012.2480845-1-arnd@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/amd/display: use div_s64() for 64-bit division | expand |
[AMD Public Use] Hi Arnd Bergmann, Thanks for your patch. This link error during compile has been fixed by below commit and been submitted to drm-next branch already. 5da047444e82 drm/amd/display: fix 64-bit division issue on 32-bit OS Regards, Guchun -----Original Message----- From: amd-gfx <amd-gfx-bounces@lists.freedesktop.org> On Behalf Of Arnd Bergmann Sent: Monday, January 25, 2021 7:40 PM To: Wentland, Harry <Harry.Wentland@amd.com>; Li, Sun peng (Leo) <Sunpeng.Li@amd.com>; Deucher, Alexander <Alexander.Deucher@amd.com>; Koenig, Christian <Christian.Koenig@amd.com>; David Airlie <airlied@linux.ie>; Daniel Vetter <daniel@ffwll.ch>; Aberback, Joshua <Joshua.Aberback@amd.com>; Lakha, Bhawanpreet <Bhawanpreet.Lakha@amd.com>; Kazlauskas, Nicholas <Nicholas.Kazlauskas@amd.com> Cc: Arnd Bergmann <arnd@arndb.de>; Chalmers, Wesley <Wesley.Chalmers@amd.com>; Zhuo, Qingqing <Qingqing.Zhuo@amd.com>; Siqueira, Rodrigo <Rodrigo.Siqueira@amd.com>; linux-kernel@vger.kernel.org; amd-gfx@lists.freedesktop.org; dri-devel@lists.freedesktop.org; Jacky Liao <ziyu.liao@amd.com>; Leung, Martin <Martin.Leung@amd.com> Subject: [PATCH] drm/amd/display: use div_s64() for 64-bit division From: Arnd Bergmann <arnd@arndb.de> The open-coded 64-bit division causes a link error on 32-bit machines: ERROR: modpost: "__udivdi3" [drivers/gpu/drm/amd/amdgpu/amdgpu.ko] undefined! ERROR: modpost: "__divdi3" [drivers/gpu/drm/amd/amdgpu/amdgpu.ko] undefined! Use the div_s64() to perform the division here. One of them was an unsigned division originally, but it looks like signed division was intended, so use that to consistently allow a negative delay. Fixes: ea7154d8d9fb ("drm/amd/display: Update dcn30_apply_idle_power_optimizations() code") Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c b/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c index dff83c6a142a..a133e399e76d 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c +++ b/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c @@ -772,8 +772,8 @@ bool dcn30_apply_idle_power_optimizations(struct dc *dc, bool enable) cursor_cache_enable ? &cursor_attr : NULL)) { unsigned int v_total = stream->adjust.v_total_max ? stream->adjust.v_total_max : stream->timing.v_total; - unsigned int refresh_hz = (unsigned long long) stream->timing.pix_clk_100hz * - 100LL / (v_total * stream->timing.h_total); + unsigned int refresh_hz = div_s64((unsigned long long) stream->timing.pix_clk_100hz * + 100LL, v_total * stream->timing.h_total); /* * one frame time in microsec: @@ -800,8 +800,8 @@ bool dcn30_apply_idle_power_optimizations(struct dc *dc, bool enable) unsigned int denom = refresh_hz * 6528; unsigned int stutter_period = dc->current_state->perf_params.stutter_period_us; - tmr_delay = (((1000000LL + 2 * stutter_period * refresh_hz) * - (100LL + dc->debug.mall_additional_timer_percent) + denom - 1) / + tmr_delay = div_s64(((1000000LL + 2 * stutter_period * refresh_hz) * + (100LL + dc->debug.mall_additional_timer_percent) + denom - 1), denom) - 64LL; /* scale should be increased until it fits into 6 bits */ @@ -815,8 +815,8 @@ bool dcn30_apply_idle_power_optimizations(struct dc *dc, bool enable) } denom *= 2; - tmr_delay = (((1000000LL + 2 * stutter_period * refresh_hz) * - (100LL + dc->debug.mall_additional_timer_percent) + denom - 1) / + tmr_delay = div_s64(((1000000LL + 2 * stutter_period * refresh_hz) * + (100LL + dc->debug.mall_additional_timer_percent) + denom - 1), denom) - 64LL; } -- 2.29.2
On Mon, Jan 25, 2021 at 1:51 PM Chen, Guchun <Guchun.Chen@amd.com> wrote: > > [AMD Public Use] > > Hi Arnd Bergmann, > > Thanks for your patch. This link error during compile has been fixed by below commit and been submitted to drm-next branch already. > > 5da047444e82 drm/amd/display: fix 64-bit division issue on 32-bit OS Ok, thanks. I assume this will make it into linux-next in the coming days then. Arnd
diff --git a/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c b/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c index dff83c6a142a..a133e399e76d 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c +++ b/drivers/gpu/drm/amd/display/dc/dcn30/dcn30_hwseq.c @@ -772,8 +772,8 @@ bool dcn30_apply_idle_power_optimizations(struct dc *dc, bool enable) cursor_cache_enable ? &cursor_attr : NULL)) { unsigned int v_total = stream->adjust.v_total_max ? stream->adjust.v_total_max : stream->timing.v_total; - unsigned int refresh_hz = (unsigned long long) stream->timing.pix_clk_100hz * - 100LL / (v_total * stream->timing.h_total); + unsigned int refresh_hz = div_s64((unsigned long long) stream->timing.pix_clk_100hz * + 100LL, v_total * stream->timing.h_total); /* * one frame time in microsec: @@ -800,8 +800,8 @@ bool dcn30_apply_idle_power_optimizations(struct dc *dc, bool enable) unsigned int denom = refresh_hz * 6528; unsigned int stutter_period = dc->current_state->perf_params.stutter_period_us; - tmr_delay = (((1000000LL + 2 * stutter_period * refresh_hz) * - (100LL + dc->debug.mall_additional_timer_percent) + denom - 1) / + tmr_delay = div_s64(((1000000LL + 2 * stutter_period * refresh_hz) * + (100LL + dc->debug.mall_additional_timer_percent) + denom - 1), denom) - 64LL; /* scale should be increased until it fits into 6 bits */ @@ -815,8 +815,8 @@ bool dcn30_apply_idle_power_optimizations(struct dc *dc, bool enable) } denom *= 2; - tmr_delay = (((1000000LL + 2 * stutter_period * refresh_hz) * - (100LL + dc->debug.mall_additional_timer_percent) + denom - 1) / + tmr_delay = div_s64(((1000000LL + 2 * stutter_period * refresh_hz) * + (100LL + dc->debug.mall_additional_timer_percent) + denom - 1), denom) - 64LL; }