Commit 4c997c6e authored by Ville Syrjälä's avatar Ville Syrjälä
Browse files

drm/i915/bios: Extract intel_spi_read16() 



The SPI VBT codepath only knows how to read 4 bytes at a time.
So to read the 2 byte vbt_size it masks out the unwanted msbs.
Hide that little implementation detail inside a new intel_spi_read16()
helper. Alse rename the existing intel_spi_read() to intel_spi_read32()
to make it clear what it does.

Reviewed-by: default avatarJani Nikula <jani.nikula@intel.com>
Signed-off-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240923152453.11230-5-ville.syrjala@linux.intel.com
parent 3823683a

drivers/gpu/drm/i915/display/intel_bios.c

+10 −6
Original line number Diff line number Diff line
@@ -3053,13 +3053,18 @@ static struct vbt_header *firmware_get_vbt(struct intel_display *display, 
	return vbt;

}



static u32 intel_spi_read(struct intel_uncore *uncore, u32 offset)

static u32 intel_spi_read32(struct intel_uncore *uncore, u32 offset)

{

	intel_uncore_write(uncore, PRIMARY_SPI_ADDRESS, offset);



	return intel_uncore_read(uncore, PRIMARY_SPI_TRIGGER);

}



static u16 intel_spi_read16(struct intel_uncore *uncore, u32 offset)

{

	return intel_spi_read32(uncore, offset) & 0xffff;

}



static struct vbt_header *spi_oprom_get_vbt(struct intel_display *display,

					    size_t *size)

{
@@ -3078,7 +3083,7 @@ static struct vbt_header *spi_oprom_get_vbt(struct intel_display *display, 
	oprom_offset &= OROM_OFFSET_MASK;



	for (count = 0; count < oprom_size; count += 4) {

		data = intel_spi_read(&i915->uncore, oprom_offset + count);

		data = intel_spi_read32(&i915->uncore, oprom_offset + count);

		if (data == *((const u32 *)"$VBT")) {

			found = oprom_offset + count;

			break;
@@ -3094,9 +3099,8 @@ static struct vbt_header *spi_oprom_get_vbt(struct intel_display *display, 
	}



	/* Get VBT size and allocate space for the VBT */

	vbt_size = intel_spi_read(&i915->uncore,

	vbt_size = intel_spi_read16(&i915->uncore,

				    found + offsetof(struct vbt_header, vbt_size));

	vbt_size &= 0xffff;



	if (vbt_size > oprom_size - count) {

		drm_dbg_kms(display->drm,
@@ -3109,7 +3113,7 @@ static struct vbt_header *spi_oprom_get_vbt(struct intel_display *display, 
		goto err_not_found;



	for (count = 0; count < vbt_size; count += 4)

		*(vbt + store++) = intel_spi_read(&i915->uncore, found + count);

		*(vbt + store++) = intel_spi_read32(&i915->uncore, found + count);



	if (!intel_bios_is_valid_vbt(display, vbt, vbt_size))

		goto err_free_vbt;