[SRU][N/O][PATCH] drm/amd/display: Add check for granularity in dml ceil/floor helpers

[Timo Aaltonen]

From: Roman Li <Roman.Li at amd.com>

BugLink: https://bugs.launchpad.net/bugs/2098080

[Why]
Wrapper functions for dcn_bw_ceil2() and dcn_bw_floor2()
should check for granularity is non zero to avoid assert and
divide-by-zero error in dcn_bw_ functions.

[How]
Add check for granularity 0.

Cc: Mario Limonciello <mario.limonciello at amd.com>
Reviewed-by: Alvin Lee <alvin.lee2 at amd.com>
Signed-off-by: Roman Li <Roman.Li at amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler at amd.com>
Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
(cherry picked from commit f6e09701c3eb2ccb8cb0518e0b67f1c69742a4ec)
Signed-off-by: Timo Aaltonen <timo.aaltonen at canonical.com>
---
 drivers/gpu/drm/amd/display/dc/dml/dml_inline_defs.h | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/dc/dml/dml_inline_defs.h b/drivers/gpu/drm/amd/display/dc/dml/dml_inline_defs.h
index 072bd05396059..6b2ab4ec2b5ff 100644
--- a/drivers/gpu/drm/amd/display/dc/dml/dml_inline_defs.h
+++ b/drivers/gpu/drm/amd/display/dc/dml/dml_inline_defs.h
@@ -66,11 +66,15 @@ static inline double dml_max5(double a, double b, double c, double d, double e)
 
 static inline double dml_ceil(double a, double granularity)
 {
+	if (granularity == 0)
+		return 0;
 	return (double) dcn_bw_ceil2(a, granularity);
 }
 
 static inline double dml_floor(double a, double granularity)
 {
+	if (granularity == 0)
+		return 0;
 	return (double) dcn_bw_floor2(a, granularity);
 }
 
@@ -114,11 +118,15 @@ static inline double dml_ceil_2(double f)
 
 static inline double dml_ceil_ex(double x, double granularity)
 {
+	if (granularity == 0)
+		return 0;
 	return (double) dcn_bw_ceil2(x, granularity);
 }
 
 static inline double dml_floor_ex(double x, double granularity)
 {
+	if (granularity == 0)
+		return 0;
 	return (double) dcn_bw_floor2(x, granularity);
 }
 
-- 
2.45.2