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Subject[PATCH] drm/msm/dpu: avoid open-coded 64-bit division
64-bit integer division is normally not allowed in the kernel
because of the large overhead on 32-bit machines:

drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.o: in function `_dpu_core_perf_crtc_update_bus':
dpu_core_perf.c:(.text+0x810): undefined reference to `__aeabi_uldivmod'

The function already contains a call to do_div(), so I assume this
is never called in a performance critical context, and we can
use div_u64 for the second one as well.

Fixes: 04d9044f6c57 ("drm/msm/dpu: add support for clk and bw scaling for display")
Signed-off-by: Arnd Bergmann <>
include/linux/interconnect.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/interconnect.h b/include/linux/interconnect.h
index 3a63d98613fc..8279fe9b2082 100644
--- a/include/linux/interconnect.h
+++ b/include/linux/interconnect.h
@@ -11,7 +11,7 @@
#include <linux/types.h>

/* macros for converting to icc units */
-#define Bps_to_icc(x) ((x) / 1000)
+#define Bps_to_icc(x) div_u64((x), 1000)
#define kBps_to_icc(x) (x)
#define MBps_to_icc(x) ((x) * 1000)
#define GBps_to_icc(x) ((x) * 1000 * 1000)
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