From: Lucas De Marchi Date: Tue, 26 Nov 2019 22:51:10 +0000 (-0800) Subject: drm/i915/bios: assume vbt is 4-byte aligned into oprom X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=98cf5c9a482d975b91d2cf00e09c061b535b8ee4;p=linux.git drm/i915/bios: assume vbt is 4-byte aligned into oprom The unaligned ioread32() will make us read byte by byte looking for the vbt. We could just as well have done a ioread8() + a shift and avoid the extra confusion on how we are looking for "$VBT". However when using ACPI it's guaranteed the VBT is 4-byte aligned per spec, so we can probably assume it here as well. v2: do not try to simplify the loop by eliminating the auxiliary counter (Jani and Ville) Signed-off-by: Lucas De Marchi Reviewed-by: Jani Nikula Link: https://patchwork.freedesktop.org/patch/msgid/20191126225110.8127-4-lucas.demarchi@intel.com --- diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c index b75db4a2e42f0..1aeecdd02293e 100644 --- a/drivers/gpu/drm/i915/display/intel_bios.c +++ b/drivers/gpu/drm/i915/display/intel_bios.c @@ -1938,7 +1938,7 @@ static struct vbt_header *oprom_get_vbt(struct drm_i915_private *dev_priv) return NULL; /* Scour memory looking for the VBT signature. */ - for (i = 0; i + 4 < size; i++) { + for (i = 0; i + 4 < size; i += 4) { if (ioread32(oprom + i) != *((const u32 *)"$VBT")) continue;