[ Upstream commit e49f69363adf8920883fff7e8ffecb802d897c6b ]
[why]
The existing calculation uses a wrong formula to
calculate bandwidth from timing.
[how]
Expose the existing proper function that calculates the bandwidth,
so dc_link can use it to calculate timing bandwidth correctly.
Signed-off-by: Wenjing Liu <wenjing....@amd.com>
Reviewed-by: Jun Lei <jun....@amd.com>
Acked-by: Leo Li <sunpeng...@amd.com>
Signed-off-by: Alex Deucher <alexander.deuc...@amd.com>
Signed-off-by: Sasha Levin <sas...@kernel.org>
---
drivers/gpu/drm/amd/display/dc/core/dc_link.c | 48 ++++++++++++++++-
.../gpu/drm/amd/display/dc/core/dc_link_dp.c | 51 +------------------
drivers/gpu/drm/amd/display/dc/dc_link.h | 2 +
3 files changed, 51 insertions(+), 50 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
index ea18e9c2d8cea..ea2f271e234bd 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -2316,7 +2316,7 @@ static struct fixed31_32 get_pbn_from_timing(struct
pipe_ctx *pipe_ctx)
uint32_t denominator;
bpc = get_color_depth(pipe_ctx->stream_res.pix_clk_params.color_depth);
- kbps = pipe_ctx->stream_res.pix_clk_params.requested_pix_clk_100hz / 10
* bpc * 3;
+ kbps = dc_bandwidth_in_kbps_from_timing(&pipe_ctx->stream->timing);
/*
* margin 5300ppm + 300ppm ~ 0.6% as per spec, factor is 1.006
@@ -2736,3 +2736,49 @@ void dc_link_enable_hpd_filter(struct dc_link *link,
bool enable)
}
}
+uint32_t dc_bandwidth_in_kbps_from_timing(
+ const struct dc_crtc_timing *timing)
+{
+ uint32_t bits_per_channel = 0;
+ uint32_t kbps;
+
+ switch (timing->display_color_depth) {
+ case COLOR_DEPTH_666:
+ bits_per_channel = 6;
+ break;
+ case COLOR_DEPTH_888:
+ bits_per_channel = 8;
+ break;
+ case COLOR_DEPTH_101010:
+ bits_per_channel = 10;
+ break;
+ case COLOR_DEPTH_121212:
+ bits_per_channel = 12;
+ break;
+ case COLOR_DEPTH_141414:
+ bits_per_channel = 14;
+ break;
+ case COLOR_DEPTH_161616:
+ bits_per_channel = 16;
+ break;
+ default:
+ break;
+ }
+
+ ASSERT(bits_per_channel != 0);
+
+ kbps = timing->pix_clk_100hz / 10;
+ kbps *= bits_per_channel;
+
+ if (timing->flags.Y_ONLY != 1) {
+ /*Only YOnly make reduce bandwidth by 1/3 compares to RGB*/
+ kbps *= 3;
+ if (timing->pixel_encoding == PIXEL_ENCODING_YCBCR420)
+ kbps /= 2;
+ else if (timing->pixel_encoding == PIXEL_ENCODING_YCBCR422)
+ kbps = kbps * 2 / 3;
+ }
+
+ return kbps;
+
+}
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
index 09d3012160763..6809932e80bec 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
@@ -1520,53 +1520,6 @@ static bool decide_fallback_link_setting(
return true;
}
-static uint32_t bandwidth_in_kbps_from_timing(
- const struct dc_crtc_timing *timing)
-{
- uint32_t bits_per_channel = 0;
- uint32_t kbps;
-
- switch (timing->display_color_depth) {
- case COLOR_DEPTH_666:
- bits_per_channel = 6;
- break;
- case COLOR_DEPTH_888:
- bits_per_channel = 8;
- break;
- case COLOR_DEPTH_101010:
- bits_per_channel = 10;
- break;
- case COLOR_DEPTH_121212:
- bits_per_channel = 12;
- break;
- case COLOR_DEPTH_141414:
- bits_per_channel = 14;
- break;
- case COLOR_DEPTH_161616:
- bits_per_channel = 16;
- break;
- default:
- break;
- }
-
- ASSERT(bits_per_channel != 0);
-
- kbps = timing->pix_clk_100hz / 10;
- kbps *= bits_per_channel;
-
- if (timing->flags.Y_ONLY != 1) {
- /*Only YOnly make reduce bandwidth by 1/3 compares to RGB*/
- kbps *= 3;
- if (timing->pixel_encoding == PIXEL_ENCODING_YCBCR420)
- kbps /= 2;
- else if (timing->pixel_encoding == PIXEL_ENCODING_YCBCR422)
- kbps = kbps * 2 / 3;
- }
-
- return kbps;
-
-}
-
static uint32_t bandwidth_in_kbps_from_link_settings(
const struct dc_link_settings *link_setting)
{
@@ -1607,7 +1560,7 @@ bool dp_validate_mode_timing(
link_setting = &link->verified_link_cap;
*/
- req_bw = bandwidth_in_kbps_from_timing(timing);
+ req_bw = dc_bandwidth_in_kbps_from_timing(timing);
max_bw = bandwidth_in_kbps_from_link_settings(link_setting);
if (req_bw <= max_bw) {
@@ -1641,7 +1594,7 @@ void decide_link_settings(struct dc_stream_state *stream,
uint32_t req_bw;
uint32_t link_bw;
- req_bw = bandwidth_in_kbps_from_timing(&stream->timing);
+ req_bw = dc_bandwidth_in_kbps_from_timing(&stream->timing);
link = stream->link;
diff --git a/drivers/gpu/drm/amd/display/dc/dc_link.h
b/drivers/gpu/drm/amd/display/dc/dc_link.h
index 8fc223defed4a..a83e1c60f9db2 100644
--- a/drivers/gpu/drm/amd/display/dc/dc_link.h
+++ b/drivers/gpu/drm/amd/display/dc/dc_link.h
@@ -252,4 +252,6 @@ bool dc_submit_i2c(
uint32_t link_index,
struct i2c_command *cmd);
+uint32_t dc_bandwidth_in_kbps_from_timing(
+ const struct dc_crtc_timing *timing);
#endif /* DC_LINK_H_ */
--
2.20.1
