[PATCH resend] drm/i915/bios: Apply vlv_fixup_mipi_sequences() to v2 mipi-sequences too
Hans de Goede
hansg at kernel.org
Mon Jul 7 21:10:59 UTC 2025
Hi Ville,
On 4-Jul-25 12:31 PM, Ville Syrjälä wrote:
> On Thu, Jul 03, 2025 at 04:38:24PM +0200, Hans de Goede wrote:
>> From: Hans de Goede <hdegoede at redhat.com>
>>
>> It turns out that the fixup from vlv_fixup_mipi_sequences() is necessary
>> for some DSI panel's with version 2 mipi-sequences too.
>>
>> Specifically the Acer Iconia One 8 A1-840 (not to be confused with the
>> A1-840FHD which is different) has the following sequences:
>>
>> BDB block 53 (1284 bytes) - MIPI sequence block:
>> Sequence block version v2
>> Panel 0 *
>>
>> Sequence 2 - MIPI_SEQ_INIT_OTP
>> GPIO index 9, source 0, set 0 (0x00)
>> Delay: 50000 us
>> GPIO index 9, source 0, set 1 (0x01)
>> Delay: 6000 us
>> GPIO index 9, source 0, set 0 (0x00)
>> Delay: 6000 us
>> GPIO index 9, source 0, set 1 (0x01)
>> Delay: 25000 us
>> Send DCS: Port A, VC 0, LP, Type 39, Length 5, Data ff aa 55 a5 80
>> Send DCS: Port A, VC 0, LP, Type 39, Length 3, Data 6f 11 00
>> ...
>> Send DCS: Port A, VC 0, LP, Type 05, Length 1, Data 29
>> Delay: 120000 us
>>
>> Sequence 4 - MIPI_SEQ_DISPLAY_OFF
>> Send DCS: Port A, VC 0, LP, Type 05, Length 1, Data 28
>> Delay: 105000 us
>> Send DCS: Port A, VC 0, LP, Type 05, Length 2, Data 10 00
>> Delay: 10000 us
>>
>> Sequence 5 - MIPI_SEQ_ASSERT_RESET
>> Delay: 10000 us
>> GPIO index 9, source 0, set 0 (0x00)
>>
>> Notice how there is no MIPI_SEQ_DEASSERT_RESET, instead the deassert
>> is done at the beginning of MIPI_SEQ_INIT_OTP, which is exactly what
>> the fixup from vlv_fixup_mipi_sequences() fixes up.
>>
>> Extend it to also apply to v2 sequences, this fixes the panel not working
>> on the Acer Iconia One 8 A1-840.
>
> Do we have the full VBT for this machine already in some bug? If not,
> please file a new issue with the VBT attached for posterity.
I've filed: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14605
with the VBT attached and I'll add a Closes: tag pointing to that
to the patch while applying it to drm-intel-fixes.
Regards,
Hans
>
>>
>> Signed-off-by: Hans de Goede <hdegoede at redhat.com>
>> ---
>> drivers/gpu/drm/i915/display/intel_bios.c | 8 ++++----
>> 1 file changed, 4 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c
>> index ba7b8938b17c..166ee11831ab 100644
>> --- a/drivers/gpu/drm/i915/display/intel_bios.c
>> +++ b/drivers/gpu/drm/i915/display/intel_bios.c
>> @@ -1938,7 +1938,7 @@ static int get_init_otp_deassert_fragment_len(struct intel_display *display,
>> int index, len;
>>
>> if (drm_WARN_ON(display->drm,
>> - !data || panel->vbt.dsi.seq_version != 1))
>> + !data || panel->vbt.dsi.seq_version >= 3))
>> return 0;
>>
>> /* index = 1 to skip sequence byte */
>> @@ -1961,7 +1961,7 @@ static int get_init_otp_deassert_fragment_len(struct intel_display *display,
>> }
>>
>> /*
>> - * Some v1 VBT MIPI sequences do the deassert in the init OTP sequence.
>> + * Some v1/v2 VBT MIPI sequences do the deassert in the init OTP sequence.
>> * The deassert must be done before calling intel_dsi_device_ready, so for
>> * these devices we split the init OTP sequence into a deassert sequence and
>> * the actual init OTP part.
>> @@ -1972,9 +1972,9 @@ static void vlv_fixup_mipi_sequences(struct intel_display *display,
>> u8 *init_otp;
>> int len;
>>
>> - /* Limit this to v1 vid-mode sequences */
>> + /* Limit this to v1/v2 vid-mode sequences */
>> if (panel->vbt.dsi.config->is_cmd_mode ||
>> - panel->vbt.dsi.seq_version != 1)
>> + panel->vbt.dsi.seq_version >= 3)
>> return;
>>
>> /* Only do this if there are otp and assert seqs and no deassert seq */
>> --
>> 2.49.0
>
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