tmakin/tegra-linux-noble
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

drm/i915/psr: Improve fast and IO wake lines calculation

Browse Source 
BugLink: https://bugs.launchpad.net/bugs/2046315

Current fast and IO wake lines calculation is assuming fast wake sync
length is 18 pulses. Let's improve this by checking actual length.

Add getter for IO buffer wake time and return 10 us there which was assumed
with static 42 us IO wake time. Upcoming patches will extent this for
different display versions.

Bspec: 65450

v3:
  - s/get_io_buffer_wake_time/io_buffer_wake_time/ and use it directly in
    calculation.
v2:
  - rename io_wake_time in if block to io_buffer_wake_time
  - rename get_io_wake_time to get_io_buffer_wake_time

Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240313133221.868391-3-jouni.hogander@intel.com
(cherry picked from commit fe10e7c681a147d4635a83706528d5caf349a978 linux-next)
Signed-off-by: Hui Wang <hui.wang@canonical.com>
Acked-by: Timo Aaltonen <timo.aaltonen@canonical.com>
Acked-by: Guoqing Jiang <guoqing.jiang@canonical.com>
Signed-off-by: Roxana Nicolescu <roxana.nicolescu@canonical.com>
This commit is contained in:
Jouni Högander
2024-04-16 14:04:14 +08:00
committed by Stefan Bader
parent 65917d45a8
commit 307476565e
1 changed files with 14 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files
drivers/gpu/drm/i915/display/intel_psr.c
+14 -6
View File
@@ -1127,6 +1127,11 @@ static bool _lnl_compute_alpm_params(struct intel_dp *intel_dp,
return true;
}
static int io_buffer_wake_time(void)
{
return 10;
}
static bool _compute_alpm_params(struct intel_dp *intel_dp,
struct intel_crtc_state *crtc_state)
{
@@ -1135,12 +1140,15 @@ static bool _compute_alpm_params(struct intel_dp *intel_dp,
u8 max_wake_lines;
if (DISPLAY_VER(i915) >= 12) {
io_wake_time = 42;
/*
* According to Bspec it's 42us, but based on testing
* it is not enough -> use 45 us.
*/
fast_wake_time = 45;
int tfw_exit_latency = 20; /* eDP spec */
int phy_wake = 4; /* eDP spec */
int preamble = 8; /* eDP spec */
int precharge = intel_dp_aux_fw_sync_len() - preamble;
io_wake_time = max(precharge, io_buffer_wake_time()) + preamble +
phy_wake + tfw_exit_latency;
fast_wake_time = precharge + preamble + phy_wake +
tfw_exit_latency;
/* TODO: Check how we can use ALPM_CTL fast wake extended field */
max_wake_lines = 12;