drm/r128: Fix undefined behavior due to shift overflowing the constant

Fix:

  drivers/gpu/drm/r128/r128_cce.c: In function ‘r128_do_init_cce’:
  drivers/gpu/drm/r128/r128_cce.c:417:2: error: case label does not reduce to an integer constant
    case R128_PM4_64BM_64VCBM_64INDBM:
    ^~~~
  drivers/gpu/drm/r128/r128_cce.c:418:2: error: case label does not reduce to an integer constant
    case R128_PM4_64PIO_64VCPIO_64INDPIO:
    ^~~~

See https://lore.kernel.org/r/YkwQ6%2BtIH8GQpuct@zn.tnic for the gory
details as to why it triggers with older gccs only.

Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220405151517.29753-5-bp@alien8.de

diff --git a/drivers/gpu/drm/r128/r128_drv.h b/drivers/gpu/drm/r128/r128_drv.h
index 2e1bc01aa5c9833b91e4c6bc9e9c3cc939a484dd..970e192b0d515d1c842e7ecbfc9ba09d12f569d0 100644 (file)
--- a/drivers/gpu/drm/r128/r128_drv.h
+++ b/drivers/gpu/drm/r128/r128_drv.h
@@ -300,8 +300,8 @@ extern long r128_compat_ioctl(struct file *filp, unsigned int cmd,
 #      define R128_PM4_64PIO_128INDBM          (5  << 28)
 #      define R128_PM4_64BM_128INDBM           (6  << 28)
 #      define R128_PM4_64PIO_64VCBM_64INDBM    (7  << 28)
-#      define R128_PM4_64BM_64VCBM_64INDBM     (8  << 28)
-#      define R128_PM4_64PIO_64VCPIO_64INDPIO  (15 << 28)
+#      define R128_PM4_64BM_64VCBM_64INDBM     (8U  << 28)
+#      define R128_PM4_64PIO_64VCPIO_64INDPIO  (15U << 28)
 #      define R128_PM4_BUFFER_CNTL_NOUPDATE    (1  << 27)
 
 #define R128_PM4_BUFFER_WM_CNTL                0x0708