On 01.01.2016 14:07, Arnd Bergmann wrote:
The newly added code for Fiji creates a correct compiler warning
about invalid use of the do_div macro:

In file included from powerplay/hwmgr/ppatomctrl.c:31:0:
drivers/gpu/drm/amd/amdgpu/../powerplay/hwmgr/ppevvmath.h: In function 
'fDivide':
drivers/gpu/drm/amd/amdgpu/../powerplay/hwmgr/ppevvmath.h:382:89: warning: 
comparison of distinct pointer types lacks a cast
      do_div(longlongX, longlongY); /*Q(32,32) divided by Q(16,16) = Q(16,16) 
Back to original format */

do_div() divides an unsigned 64-bit number by an unsigned 32-bit number.
The code instead wants to divide two signed 64-bit numbers, which is done
using the div64_s64 function.

Signed-off-by: Arnd Bergmann <a...@arndb.de>

Reviewed-by: Christian König <christian.koe...@amd.com>

Fixes: 770911a3cfbb ("drm/amd/powerplay: add/update headers for Fiji SMU and 
DPM")
---
Found on ARM allmodconfig on yesterday's linux-next

diff --git a/drivers/gpu/drm/amd/powerplay/hwmgr/ppevvmath.h 
b/drivers/gpu/drm/amd/powerplay/hwmgr/ppevvmath.h
index 42f2423cddea..411cb0fcdf98 100644
--- a/drivers/gpu/drm/amd/powerplay/hwmgr/ppevvmath.h
+++ b/drivers/gpu/drm/amd/powerplay/hwmgr/ppevvmath.h
@@ -379,7 +379,7 @@ fInt fDivide (fInt X, fInt Y)
longlongX = longlongX << 16; /*Q(16,16) -> Q(32,32) */ - do_div(longlongX, longlongY); /*Q(32,32) divided by Q(16,16) = Q(16,16) Back to original format */
+    div64_s64(longlongX, longlongY); /*Q(32,32) divided by Q(16,16) = Q(16,16) 
Back to original format */
fQuotient.full = (int)longlongX;
      return fQuotient;


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to