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Commit 2a33d934 authored by Jani Nikula's avatar Jani Nikula
Browse files

drm/i915/bios: add support for MIPI sequence block v3 



The changes since the sequence block v2 are:

* The whole MIPI bios data block has a separate 32-bit size field since
  v3, stored after the version. This facilitates big sequences.

* The size of the panel specific sequence blocks has grown to 32
  bits. This facilitates big sequences.

* The elements within sequences now have an 8-bit size field following
  the operation byte. This facilitates skipping unknown new operation
  bytes, i.e. forward compatibility.

v2 (of the patch): use DRM_ERROR for unknown operation byte
v3 (of the patch): even more bounds checking (Ville)

Reviewed-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: default avatarJani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1452518102-3154-1-git-send-email-jani.nikula@intel.com
parent 4b42dfbb

drivers/gpu/drm/i915/intel_bios.c

+85 −11
Original line number Diff line number Diff line
@@ -754,21 +754,33 @@ parse_mipi_config(struct drm_i915_private *dev_priv, 
/* Find the sequence block and size for the given panel. */

static const u8 *

find_panel_sequence_block(const struct bdb_mipi_sequence *sequence,

			  u16 panel_id, u16 *seq_size)

			  u16 panel_id, u32 *seq_size)

{

	u32 total = get_blocksize(sequence);

	const u8 *data = &sequence->data[0];

	u8 current_id;

	u16 current_size;

	u32 current_size;

	int header_size = sequence->version >= 3 ? 5 : 3;

	int index = 0;

	int i;



	for (i = 0; i < MAX_MIPI_CONFIGURATIONS && index + 3 < total; i++) {

	/* skip new block size */

	if (sequence->version >= 3)

		data += 4;



	for (i = 0; i < MAX_MIPI_CONFIGURATIONS && index < total; i++) {

		if (index + header_size > total) {

			DRM_ERROR("Invalid sequence block (header)\n");

			return NULL;

		}



		current_id = *(data + index);

		index++;

		if (sequence->version >= 3)

			current_size = *((const u32 *)(data + index + 1));

		else

			current_size = *((const u16 *)(data + index + 1));



		current_size = *((const u16 *)(data + index));

		index += 2;

		index += header_size;



		if (index + current_size > total) {

			DRM_ERROR("Invalid sequence block\n");
@@ -826,13 +838,71 @@ static int goto_next_sequence(const u8 *data, int index, int total) 
	return 0;

}



static int goto_next_sequence_v3(const u8 *data, int index, int total)

{

	int seq_end;

	u16 len;



	/*

	 * Could skip sequence based on Size of Sequence alone, but also do some

	 * checking on the structure.

	 */

	if (total < 5) {

		DRM_ERROR("Too small sequence size\n");

		return 0;

	}



	seq_end = index + *((const u32 *)(data + 1));

	if (seq_end > total) {

		DRM_ERROR("Invalid sequence size\n");

		return 0;

	}



	/* Skip Sequence Byte and Size of Sequence. */

	for (index = index + 5; index < total; index += len) {

		u8 operation_byte = *(data + index);

		index++;



		if (operation_byte == MIPI_SEQ_ELEM_END) {

			if (index != seq_end) {

				DRM_ERROR("Invalid element structure\n");

				return 0;

			}

			return index;

		}



		len = *(data + index);

		index++;



		/*

		 * FIXME: Would be nice to check elements like for v1/v2 in

		 * goto_next_sequence() above.

		 */

		switch (operation_byte) {

		case MIPI_SEQ_ELEM_SEND_PKT:

		case MIPI_SEQ_ELEM_DELAY:

		case MIPI_SEQ_ELEM_GPIO:

		case MIPI_SEQ_ELEM_I2C:

		case MIPI_SEQ_ELEM_SPI:

		case MIPI_SEQ_ELEM_PMIC:

			break;

		default:

			DRM_ERROR("Unknown operation byte %u\n",

				  operation_byte);

			break;

		}

	}



	return 0;

}



static void

parse_mipi_sequence(struct drm_i915_private *dev_priv,

		    const struct bdb_header *bdb)

{

	const struct bdb_mipi_sequence *sequence;

	const u8 *seq_data;

	u16 seq_size;

	u32 seq_size;

	u8 *data;

	int index = 0;
@@ -847,12 +917,13 @@ parse_mipi_sequence(struct drm_i915_private *dev_priv, 
	}



	/* Fail gracefully for forward incompatible sequence block. */

	if (sequence->version >= 3) {

		DRM_ERROR("Unable to parse MIPI Sequence Block v3+\n");

	if (sequence->version >= 4) {

		DRM_ERROR("Unable to parse MIPI Sequence Block v%u\n",

			  sequence->version);

		return;

	}



	DRM_DEBUG_DRIVER("Found MIPI sequence block\n");

	DRM_DEBUG_DRIVER("Found MIPI sequence block v%u\n", sequence->version);



	seq_data = find_panel_sequence_block(sequence, panel_type, &seq_size);

	if (!seq_data)
@@ -875,6 +946,9 @@ parse_mipi_sequence(struct drm_i915_private *dev_priv, 


		dev_priv->vbt.dsi.sequence[seq_id] = data + index;



		if (sequence->version >= 3)

			index = goto_next_sequence_v3(data, index, seq_size);

		else

			index = goto_next_sequence(data, index, seq_size);

		if (!index) {

			DRM_ERROR("Invalid sequence %u\n", seq_id);

drivers/gpu/drm/i915/intel_dsi_panel_vbt.c

+9 −0
Original line number Diff line number Diff line
@@ -267,6 +267,7 @@ static const char *sequence_name(enum mipi_seq seq_id) 


static void generic_exec_sequence(struct intel_dsi *intel_dsi, const u8 *data)

{

	struct drm_i915_private *dev_priv = to_i915(intel_dsi->base.base.dev);

	fn_mipi_elem_exec mipi_elem_exec;



	if (!data)
@@ -278,6 +279,10 @@ static void generic_exec_sequence(struct intel_dsi *intel_dsi, const u8 *data) 
	/* go to the first element of the sequence */

	data++;



	/* Skip Size of Sequence. */

	if (dev_priv->vbt.dsi.seq_version >= 3)

		data += 4;



	/* parse each byte till we reach end of sequence byte - 0x00 */

	while (1) {

		u8 operation_byte = *data++;
@@ -289,6 +294,10 @@ static void generic_exec_sequence(struct intel_dsi *intel_dsi, const u8 *data) 
		}

		mipi_elem_exec = exec_elem[operation_byte];



		/* Skip Size of Operation. */

		if (dev_priv->vbt.dsi.seq_version >= 3)

			data++;



		/* execute the element specific rotines */

		data = mipi_elem_exec(intel_dsi, data);