[PATCH 06/11] drm/amd/display: fix 64bit division issue on 32bit OS

[Anson Jacob]

From: Lang Yu <Lang.Yu at amd.com>

Replace "/" with div_u64 for 64bit division on 32bit OS.

Signed-off-by: Lang Yu <Lang.Yu at amd.com>
Reviewed-by: Nicholas Kazlauskas <Nicholas.Kazlauskas at amd.com>
Acked-by: Anson Jacob <Anson.Jacob at amd.com>
Acked-by: Huang Rui <ray.huang at amd.com>
---
 drivers/gpu/drm/amd/display/dc/core/dc_link.c         | 4 ++--
 drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c | 2 +-
 drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c | 3 ++-
 3 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
index 8506739a22f7..fa5059f71727 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -3688,8 +3688,8 @@ uint32_t dc_link_bandwidth_kbps(
 		 * but the difference is minimal and is in a safe direction,
 		 * which all works well around potential ambiguity of DP 1.4a spec.
 		 */
-		link_bw_kbps = mul_u64_u32_shr(BIT_ULL(32) * 970LL / 1000,
-					       link_bw_kbps, 32);
+		long long fec_link_bw_kbps = link_bw_kbps * 970LL;
+		link_bw_kbps = (uint32_t)(div64_s64(fec_link_bw_kbps, 1000LL));
 	}
 
 	return link_bw_kbps;
diff --git a/drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c b/drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c
index 17ec63253fc3..bc942725b9d8 100644
--- a/drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c
+++ b/drivers/gpu/drm/amd/display/dc/dce/dce_clock_source.c
@@ -240,7 +240,7 @@ static bool calc_fb_divider_checking_tolerance(
 		pll_settings->calculated_pix_clk_100hz =
 			actual_calculated_clock_100hz;
 		pll_settings->vco_freq =
-			actual_calculated_clock_100hz * post_divider / 10;
+			div_u64(actual_calculated_clock_100hz * post_divider, 10);
 		return true;
 	}
 	return false;
diff --git a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c
index 064f158ce671..6505373483bb 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_resource.c
@@ -3506,7 +3506,8 @@ void dcn20_update_bounding_box(struct dc *dc, struct _vcs_dpi_soc_bounding_box_s
 		calculated_states[i].dram_speed_mts = uclk_states[i] * 16 / 1000;
 
 		// FCLK:UCLK ratio is 1.08
-		min_fclk_required_by_uclk = mul_u64_u32_shr(BIT_ULL(32) * 1080 / 1000000, uclk_states[i], 32);
+		min_fclk_required_by_uclk = div_u64(((unsigned long long)uclk_states[i]) * 1080,
+			1000000);
 
 		calculated_states[i].fabricclk_mhz = (min_fclk_required_by_uclk < min_dcfclk) ?
 				min_dcfclk : min_fclk_required_by_uclk;
-- 
2.25.1