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drm/amd/display: Optimize DP_SINK_STATUS_ESI range read on HPD

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DP_SINK_STATUS_ESI range data is not continual, but rather than
getting it in two AUX reads, it's quicker to read more bytes in a
AUX read and then memcpy the required fields (it's only 8 more
bytes to read).

Signed-off-by: Nikola Cornij <nikola.cornij@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
This commit is contained in:
Nikola Cornij 2018-05-09 17:07:36 -04:00 committed by Alex Deucher
parent bf58968647
commit 3c8e4316a0
1 changed files with 13 additions and 9 deletions
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22
drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
View File

@ -1647,22 +1647,26 @@ static enum dc_status read_hpd_rx_irq_data(
irq_data->raw,
sizeof(union hpd_irq_data));
else {
/* Read 2 bytes at this location,... */
/* Read 14 bytes in a single read and then copy only the required fields.
* This is more efficient than doing it in two separate AUX reads. */
uint8_t tmp[DP_SINK_STATUS_ESI - DP_SINK_COUNT_ESI + 1];
retval = core_link_read_dpcd(
link,
DP_SINK_COUNT_ESI,
irq_data->raw,
2);
tmp,
sizeof(tmp));
if (retval != DC_OK)
return retval;
/* ... then read remaining 4 at the other location */
retval = core_link_read_dpcd(
link,
DP_LANE0_1_STATUS_ESI,
&irq_data->raw[2],
4);
irq_data->bytes.sink_cnt.raw = tmp[DP_SINK_COUNT_ESI - DP_SINK_COUNT_ESI];
irq_data->bytes.device_service_irq.raw = tmp[DP_DEVICE_SERVICE_IRQ_VECTOR_ESI0 - DP_SINK_COUNT_ESI];
irq_data->bytes.lane01_status.raw = tmp[DP_LANE0_1_STATUS_ESI - DP_SINK_COUNT_ESI];
irq_data->bytes.lane23_status.raw = tmp[DP_LANE2_3_STATUS_ESI - DP_SINK_COUNT_ESI];
irq_data->bytes.lane_status_updated.raw = tmp[DP_LANE_ALIGN_STATUS_UPDATED_ESI - DP_SINK_COUNT_ESI];
irq_data->bytes.sink_status.raw = tmp[DP_SINK_STATUS_ESI - DP_SINK_COUNT_ESI];
}
return retval;