drm/amd/display: Make DMCUB bss/data firmware blob optional

[Why]
By moving everything out of .data into the other regions we can drop
the requirement for the second blob and unify it all into the inst/const
blob.

[How]
We need to still support the blob being there and not being there for
backwards compatibility.

Look for the DMCUB metadata section in the end of the inst/const blob
instead of bss/data is missing.

Clear CW2 if we don't have the data blob so we don't hang when
transitioning between data blob/blobless firmwares.

Don't memcpy the blob into CW2 region if it doesn't exist.

Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

3 files changed, 34 insertions, 14 deletions

diff --git a/drivers/gpu/drm/amd/display/dmub/inc/dmub_srv.h b/drivers/gpu/drm/amd/display/dmub/inc/dmub_srv.h
index af678462f0e6..e40d1cdbcfaa 100644
--- a/drivers/gpu/drm/amd/display/dmub/inc/dmub_srv.h
+++ b/drivers/gpu/drm/amd/display/dmub/inc/dmub_srv.h
@@ -151,6 +151,7 @@ struct dmub_srv_region_params {
 	uint32_t inst_const_size;
 	uint32_t bss_data_size;
 	uint32_t vbios_size;
+	const uint8_t *fw_inst_const;
 	const uint8_t *fw_bss_data;
 };
 
diff --git a/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn20.c b/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn20.c
index 63bb9e2c81de..45638d61b73d 100644
--- a/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn20.c
+++ b/drivers/gpu/drm/amd/display/dmub/src/dmub_dcn20.c
@@ -186,14 +186,22 @@ void dmub_dcn20_setup_windows(struct dmub_srv *dmub,
 
 	dmub_dcn20_get_fb_base_offset(dmub, &fb_base, &fb_offset);
 
-	dmub_dcn20_translate_addr(&cw2->offset, fb_base, fb_offset, &offset);
-
-	REG_WRITE(DMCUB_REGION3_CW2_OFFSET, offset.u.low_part);
-	REG_WRITE(DMCUB_REGION3_CW2_OFFSET_HIGH, offset.u.high_part);
-	REG_WRITE(DMCUB_REGION3_CW2_BASE_ADDRESS, cw2->region.base);
-	REG_SET_2(DMCUB_REGION3_CW2_TOP_ADDRESS, 0,
-		  DMCUB_REGION3_CW2_TOP_ADDRESS, cw2->region.top,
-		  DMCUB_REGION3_CW2_ENABLE, 1);
+	if (cw2->region.base != cw2->region.top) {
+		dmub_dcn20_translate_addr(&cw2->offset, fb_base, fb_offset,
+					  &offset);
+
+		REG_WRITE(DMCUB_REGION3_CW2_OFFSET, offset.u.low_part);
+		REG_WRITE(DMCUB_REGION3_CW2_OFFSET_HIGH, offset.u.high_part);
+		REG_WRITE(DMCUB_REGION3_CW2_BASE_ADDRESS, cw2->region.base);
+		REG_SET_2(DMCUB_REGION3_CW2_TOP_ADDRESS, 0,
+			  DMCUB_REGION3_CW2_TOP_ADDRESS, cw2->region.top,
+			  DMCUB_REGION3_CW2_ENABLE, 1);
+	} else {
+		REG_WRITE(DMCUB_REGION3_CW2_OFFSET, 0);
+		REG_WRITE(DMCUB_REGION3_CW2_OFFSET_HIGH, 0);
+		REG_WRITE(DMCUB_REGION3_CW2_BASE_ADDRESS, 0);
+		REG_WRITE(DMCUB_REGION3_CW2_TOP_ADDRESS, 0);
+	}
 
 	dmub_dcn20_translate_addr(&cw3->offset, fb_base, fb_offset, &offset);
 
diff --git a/drivers/gpu/drm/amd/display/dmub/src/dmub_srv.c b/drivers/gpu/drm/amd/display/dmub/src/dmub_srv.c
index 0be8a54cc475..0a1a851741c5 100644
--- a/drivers/gpu/drm/amd/display/dmub/src/dmub_srv.c
+++ b/drivers/gpu/drm/amd/display/dmub/src/dmub_srv.c
@@ -91,17 +91,29 @@ void dmub_flush_buffer_mem(const struct dmub_fb *fb)
 }
 
 static const struct dmub_fw_meta_info *
-dmub_get_fw_meta_info(const uint8_t *fw_bss_data, uint32_t fw_bss_data_size)
+dmub_get_fw_meta_info(const struct dmub_srv_region_params *params)
 {
 	const union dmub_fw_meta *meta;
+	const uint8_t *blob = NULL;
+	uint32_t blob_size = 0;
+
+	if (params->fw_bss_data) {
+		/* Legacy metadata region. */
+		blob = params->fw_bss_data;
+		blob_size = params->bss_data_size;
+	} else if (params->fw_inst_const) {
+		/* Combined metadata region. */
+		blob = params->fw_inst_const;
+		blob_size = params->inst_const_size;
+	}
 
-	if (fw_bss_data == NULL)
+	if (!blob || !blob_size)
 		return NULL;
 
-	if (fw_bss_data_size < sizeof(union dmub_fw_meta) + DMUB_FW_META_OFFSET)
+	if (blob_size < sizeof(union dmub_fw_meta) + DMUB_FW_META_OFFSET)
 		return NULL;
 
-	meta = (const union dmub_fw_meta *)(fw_bss_data + fw_bss_data_size -
+	meta = (const union dmub_fw_meta *)(blob + blob_size -
 					    DMUB_FW_META_OFFSET -
 					    sizeof(union dmub_fw_meta));
 
@@ -247,8 +259,7 @@ dmub_srv_calc_region_info(struct dmub_srv *dmub,
 	mail->base = dmub_align(bios->top, 256);
 	mail->top = mail->base + DMUB_MAILBOX_SIZE;
 
-	fw_info = dmub_get_fw_meta_info(params->fw_bss_data,
-					params->bss_data_size);
+	fw_info = dmub_get_fw_meta_info(params);
 
 	if (fw_info) {
 		fw_state_size = fw_info->fw_region_size;