diff options
| author | Ville Syrjälä <ville.syrjala@linux.intel.com> | 2024-09-23 18:24:52 +0300 |
|---|---|---|
| committer | Ville Syrjälä <ville.syrjala@linux.intel.com> | 2024-10-01 17:30:55 +0300 |
| commit | 0667ca80024a0ffb73ac42544b152b421a205b11 (patch) | |
| tree | a4e34816e1be734ea4180ae39dd30fe00e0916b0 | |
| parent | 4c997c6e439013df942af27761edc01e1065cc27 (diff) | |
drm/i915/bios: Extract vbt_signature[]
Replace the three hand rolled "$VBT"s with a vbt_signature[]
to avoid accidents.
v2: Include terminating '\0' for safety (Jani)
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240923152453.11230-6-ville.syrjala@linux.intel.com
| -rw-r--r-- | drivers/gpu/drm/i915/display/intel_bios.c | 15 |
1 files changed, 12 insertions, 3 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c index 38ea92b4ff13..c57426940cf8 100644 --- a/drivers/gpu/drm/i915/display/intel_bios.c +++ b/drivers/gpu/drm/i915/display/intel_bios.c @@ -2964,6 +2964,9 @@ static const struct bdb_header *get_bdb_header(const struct vbt_header *vbt) return _vbt + vbt->bdb_offset; } +static const char vbt_signature[] = "$VBT"; +static const int vbt_signature_len = 4; + /** * intel_bios_is_valid_vbt - does the given buffer contain a valid VBT * @display: display device @@ -2986,7 +2989,7 @@ bool intel_bios_is_valid_vbt(struct intel_display *display, return false; } - if (memcmp(vbt->signature, "$VBT", 4)) { + if (memcmp(vbt->signature, vbt_signature, vbt_signature_len)) { drm_dbg_kms(display->drm, "VBT invalid signature\n"); return false; } @@ -3082,9 +3085,12 @@ static struct vbt_header *spi_oprom_get_vbt(struct intel_display *display, oprom_offset = intel_uncore_read(&i915->uncore, OROM_OFFSET); oprom_offset &= OROM_OFFSET_MASK; + BUILD_BUG_ON(vbt_signature_len != sizeof(vbt_signature) - 1); + BUILD_BUG_ON(vbt_signature_len != sizeof(u32)); + for (count = 0; count < oprom_size; count += 4) { data = intel_spi_read32(&i915->uncore, oprom_offset + count); - if (data == *((const u32 *)"$VBT")) { + if (data == *((const u32 *)vbt_signature)) { found = oprom_offset + count; break; } @@ -3144,9 +3150,12 @@ static struct vbt_header *oprom_get_vbt(struct intel_display *display, if (!oprom) return NULL; + BUILD_BUG_ON(vbt_signature_len != sizeof(vbt_signature) - 1); + BUILD_BUG_ON(vbt_signature_len != sizeof(u32)); + /* Scour memory looking for the VBT signature. */ for (i = 0; i + 4 < size; i += 4) { - if (ioread32(oprom + i) != *((const u32 *)"$VBT")) + if (ioread32(oprom + i) != *((const u32 *)vbt_signature)) continue; p = oprom + i; |