lkml.org 
[lkml]   [2022]   [Jan]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [v9,2/3] drm/mediatek: implement the DSI hs packets aligned
From

On 14.01.2022 11:20, Rex-BC Chen wrote:
> Hello AngeloGioacchino,
>
> Thanks for your review.
> I will modify this in next version.
>
> BRs,
> Rex-BC Chen
>
> On Fri, 2022-01-14 at 10:36 +0100, AngeloGioacchino Del Regno wrote:
>> Il 14/01/22 10:21, Rex-BC Chen ha scritto:
>>> Some DSI RX devices require the packets on all lanes aligned at the
>>> end.
>>> Otherwise, there will be some issues of shift or scroll for screen.
>>>
>>> Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
>>> Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
>> Hello,
>> thanks for the patch! However, there's something to improve...
>>
>>> ---
>>> drivers/gpu/drm/mediatek/mtk_dsi.c | 12 ++++++++++++
>>> 1 file changed, 12 insertions(+)
>>>
>>> diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c
>>> b/drivers/gpu/drm/mediatek/mtk_dsi.c
>>> index 5d90d2eb0019..ccdda15f5a66 100644
>>> --- a/drivers/gpu/drm/mediatek/mtk_dsi.c
>>> +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
>>> @@ -195,6 +195,8 @@ struct mtk_dsi {
>>> struct clk *hs_clk;
>>>
>>> u32 data_rate;
>>> + /* force dsi line end without dsi_null data */
>>> + bool hs_packet_end_aligned;
>> There's no need to introduce a new variable here...
>>>
>>> unsigned long mode_flags;
>>> enum mipi_dsi_pixel_format format;
>>> @@ -500,6 +502,13 @@ static void mtk_dsi_config_vdo_timing(struct
>>> mtk_dsi *dsi)
>>> DRM_WARN("HFP + HBP less than d-phy, FPS will under
>>> 60Hz\n");
>>> }
>>>
>>> + if (dsi->hs_packet_end_aligned) {
>> You can simply check mode_flags here:
>> if (dsi->mode_flags & MIPI_DSI_HS_PKT_END_ALIGNED) {
>>
>>> + horizontal_sync_active_byte =
>>> roundup(horizontal_sync_active_byte, dsi->lanes) - 2;
>>> + horizontal_frontporch_byte =
>>> roundup(horizontal_frontporch_byte, dsi->lanes) - 2;
>>> + horizontal_backporch_byte =
>>> roundup(horizontal_backporch_byte, dsi->lanes) - 2;
>>> + horizontal_backporch_byte -= (vm->hactive *
>>> dsi_tmp_buf_bpp + 2) % dsi->lanes;
>>> + }
>>> +


And if you could add comment explaining the magic here it would be nice.


Regards

Andrzej


>>> writel(horizontal_sync_active_byte, dsi->regs + DSI_HSA_WC);
>>> writel(horizontal_backporch_byte, dsi->regs + DSI_HBP_WC);
>>> writel(horizontal_frontporch_byte, dsi->regs + DSI_HFP_WC);
>>> @@ -794,6 +803,9 @@ static int mtk_dsi_host_attach(struct
>>> mipi_dsi_host *host,
>>> dsi->lanes = device->lanes;
>>> dsi->format = device->format;
>>> dsi->mode_flags = device->mode_flags;
>>> + dsi->hs_packet_end_aligned = (dsi->mode_flags &
>>> + MIPI_DSI_HS_PKT_END_ALIGNED)
>>> + ? true : false;
>> ...so there's no need for this one, either.
>>
>>>
>>> return 0;
>>> }
>>>
>> Regards,
>> - Angelo
>>

\
 
 \ /
  Last update: 2022-01-14 12:13    [W:0.055 / U:0.156 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site