[PATCH 5.2 54/56] drm/i915/vbt: Fix VBT parsing for the PSR section

From: Greg Kroah-Hartman
Date: Thu Aug 08 2019 - 15:08:00 EST


From: Dhinakaran Pandiyan <dhinakaran.pandiyan@xxxxxxxxx>

commit 6d61f716a01ec0e134de38ae97e71d6fec5a6ff6 upstream.

A single 32-bit PSR2 training pattern field follows the sixteen element
array of PSR table entries in the VBT spec. But, we incorrectly define
this PSR2 field for each of the PSR table entries. As a result, the PSR1
training pattern duration for any panel_type != 0 will be parsed
incorrectly. Secondly, PSR2 training pattern durations for VBTs with bdb
version >= 226 will also be wrong.

Cc: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
Cc: Josà Roberto de Souza <jose.souza@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Cc: stable@xxxxxxxxxxxxxxx #v5.2
Fixes: 88a0d9606aff ("drm/i915/vbt: Parse and use the new field with PSR2 TP2/3 wakeup time")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111088
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=204183
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@xxxxxxxxx>
Reviewed-by: Ville SyrjÃlà <ville.syrjala@xxxxxxxxxxxxxxx>
Reviewed-by: Josà Roberto de Souza <jose.souza@xxxxxxxxx>
Acked-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
Tested-by: FranÃois Guerraz <kubrick@xxxxxxxx>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20190717223451.2595-1-dhinakaran.pandiyan@xxxxxxxxx
(cherry picked from commit b5ea9c9337007d6e700280c8a60b4e10d070fb53)
Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>


---
drivers/gpu/drm/i915/intel_bios.c | 2 +-
drivers/gpu/drm/i915/intel_vbt_defs.h | 6 +++---
2 files changed, 4 insertions(+), 4 deletions(-)

--- a/drivers/gpu/drm/i915/intel_bios.c
+++ b/drivers/gpu/drm/i915/intel_bios.c
@@ -762,7 +762,7 @@ parse_psr(struct drm_i915_private *dev_p
}

if (bdb->version >= 226) {
- u32 wakeup_time = psr_table->psr2_tp2_tp3_wakeup_time;
+ u32 wakeup_time = psr->psr2_tp2_tp3_wakeup_time;

wakeup_time = (wakeup_time >> (2 * panel_type)) & 0x3;
switch (wakeup_time) {
--- a/drivers/gpu/drm/i915/intel_vbt_defs.h
+++ b/drivers/gpu/drm/i915/intel_vbt_defs.h
@@ -772,13 +772,13 @@ struct psr_table {
/* TP wake up time in multiple of 100 */
u16 tp1_wakeup_time;
u16 tp2_tp3_wakeup_time;
-
- /* PSR2 TP2/TP3 wakeup time for 16 panels */
- u32 psr2_tp2_tp3_wakeup_time;
} __packed;

struct bdb_psr {
struct psr_table psr_table[16];
+
+ /* PSR2 TP2/TP3 wakeup time for 16 panels */
+ u32 psr2_tp2_tp3_wakeup_time;
} __packed;

/*