i915: enable AVI infoframe for intel_hdmi.c [v4]

This patch enables the sending of AVI infoframes in
drivers/gpu/drm/i915/intel_hdmi.c.

My receiver currently loses sync when the HDMI output on my computer
(DG45FC motherboard) is switched from 800x600 (the BIOS resolution) to
1920x1080 as part of the boot. Fixable by switching inputs on the receiver
a couple of times.

With this patch, my receiver has not lost sync yet (> 40 tries).

Fourth version, now based on drm-intel-next from:
git://git.kernel.org/pub/scm/linux/kernel/git/ickle/drm-intel.git

Two questions still remain:

I'm assuming that the sdvo hardware also stores a header ECC byte in
the MSB of the first dword - is this correct?

Does the SDVOB and SDVOC handling in intel_hdmi_set_avi_infoframe()
look correct?

Signed-off-by: David Härdeman <david@hardeman.nu>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 22 insertions, 104 deletions

diff --git a/drivers/gpu/drm/i915/intel_sdvo.c b/drivers/gpu/drm/i915/intel_sdvo.c
index c245383cf7ed..6739a7455174 100644
--- a/drivers/gpu/drm/i915/intel_sdvo.c
+++ b/drivers/gpu/drm/i915/intel_sdvo.c
@@ -854,115 +854,33 @@ static void intel_sdvo_dump_hdmi_buf(struct intel_sdvo *intel_sdvo)
 }
 #endif
 
-static bool intel_sdvo_set_hdmi_buf(struct intel_sdvo *intel_sdvo,
-				    int index,
-				    uint8_t *data, int8_t size, uint8_t tx_rate)
-{
-    uint8_t set_buf_index[2];
-
-    set_buf_index[0] = index;
-    set_buf_index[1] = 0;
-
-    if (!intel_sdvo_write_cmd(intel_sdvo, SDVO_CMD_SET_HBUF_INDEX,
-			      set_buf_index, 2))
-	    return false;
-
-    for (; size > 0; size -= 8) {
-	if (!intel_sdvo_write_cmd(intel_sdvo, SDVO_CMD_SET_HBUF_DATA, data, 8))
-		return false;
-
-	data += 8;
-    }
-
-    return intel_sdvo_write_cmd(intel_sdvo, SDVO_CMD_SET_HBUF_TXRATE, &tx_rate, 1);
-}
-
-static uint8_t intel_sdvo_calc_hbuf_csum(uint8_t *data, uint8_t size)
-{
-	uint8_t csum = 0;
-	int i;
-
-	for (i = 0; i < size; i++)
-		csum += data[i];
-
-	return 0x100 - csum;
-}
-
-#define DIP_TYPE_AVI	0x82
-#define DIP_VERSION_AVI	0x2
-#define DIP_LEN_AVI	13
-
-struct dip_infoframe {
-	uint8_t type;
-	uint8_t version;
-	uint8_t len;
-	uint8_t checksum;
-	union {
-		struct {
-			/* Packet Byte #1 */
-			uint8_t S:2;
-			uint8_t B:2;
-			uint8_t A:1;
-			uint8_t Y:2;
-			uint8_t rsvd1:1;
-			/* Packet Byte #2 */
-			uint8_t R:4;
-			uint8_t M:2;
-			uint8_t C:2;
-			/* Packet Byte #3 */
-			uint8_t SC:2;
-			uint8_t Q:2;
-			uint8_t EC:3;
-			uint8_t ITC:1;
-			/* Packet Byte #4 */
-			uint8_t VIC:7;
-			uint8_t rsvd2:1;
-			/* Packet Byte #5 */
-			uint8_t PR:4;
-			uint8_t rsvd3:4;
-			/* Packet Byte #6~13 */
-			uint16_t top_bar_end;
-			uint16_t bottom_bar_start;
-			uint16_t left_bar_end;
-			uint16_t right_bar_start;
-		} avi;
-		struct {
-			/* Packet Byte #1 */
-			uint8_t channel_count:3;
-			uint8_t rsvd1:1;
-			uint8_t coding_type:4;
-			/* Packet Byte #2 */
-			uint8_t sample_size:2; /* SS0, SS1 */
-			uint8_t sample_frequency:3;
-			uint8_t rsvd2:3;
-			/* Packet Byte #3 */
-			uint8_t coding_type_private:5;
-			uint8_t rsvd3:3;
-			/* Packet Byte #4 */
-			uint8_t channel_allocation;
-			/* Packet Byte #5 */
-			uint8_t rsvd4:3;
-			uint8_t level_shift:4;
-			uint8_t downmix_inhibit:1;
-		} audio;
-		uint8_t payload[28];
-	} __attribute__ ((packed)) u;
-} __attribute__((packed));
-
-static bool intel_sdvo_set_avi_infoframe(struct intel_sdvo *intel_sdvo,
-					 struct drm_display_mode * mode)
+static bool intel_sdvo_set_avi_infoframe(struct intel_sdvo *intel_sdvo)
 {
 	struct dip_infoframe avi_if = {
 		.type = DIP_TYPE_AVI,
-		.version = DIP_VERSION_AVI,
+		.ver = DIP_VERSION_AVI,
 		.len = DIP_LEN_AVI,
 	};
+	uint8_t tx_rate = SDVO_HBUF_TX_VSYNC;
+	uint8_t set_buf_index[2] = { 1, 0 };
+	uint64_t *data = (uint64_t *)&avi_if;
+	unsigned i;
+
+	intel_dip_infoframe_csum(&avi_if);
+
+	if (!intel_sdvo_write_cmd(intel_sdvo, SDVO_CMD_SET_HBUF_INDEX,
+				  set_buf_index, 2))
+		return false;
+
+	for (i = 0; i < sizeof(avi_if); i += 8) {
+		if (!intel_sdvo_write_cmd(intel_sdvo, SDVO_CMD_SET_HBUF_DATA,
+					  data, 8))
+			return false;
+		data++;
+	}
 
-	avi_if.checksum = intel_sdvo_calc_hbuf_csum((uint8_t *)&avi_if,
-						    4 + avi_if.len);
-	return intel_sdvo_set_hdmi_buf(intel_sdvo, 1, (uint8_t *)&avi_if,
-				       4 + avi_if.len,
-				       SDVO_HBUF_TX_VSYNC);
+	return intel_sdvo_write_cmd(intel_sdvo, SDVO_CMD_SET_HBUF_TXRATE,
+				    &tx_rate, 1);
 }
 
 static bool intel_sdvo_set_tv_format(struct intel_sdvo *intel_sdvo)
@@ -1116,7 +1034,7 @@ static void intel_sdvo_mode_set(struct drm_encoder *encoder,
 		return;
 
 	if (intel_sdvo->is_hdmi &&
-	    !intel_sdvo_set_avi_infoframe(intel_sdvo, mode))
+	    !intel_sdvo_set_avi_infoframe(intel_sdvo))
 		return;
 
 	if (intel_sdvo->is_tv &&