lkml.org 
[lkml]   [2021]   [Jul]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v2 6/7] soc: mediatek: mmsys: Add reset controller support
From
Date
Hi Philipp,

Thank you to take a look

On 20/7/21 12:52, Philipp Zabel wrote:
> Hi Enric,
>
> On Wed, 2021-07-14 at 12:11 +0200, Enric Balletbo i Serra wrote:
>> Among other features the mmsys driver should implement a reset
>> controller to be able to reset different bits from their space.
>>
>> Cc: Jitao Shi <jitao.shi@mediatek.com>
>> Suggested-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
>> Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
>
> The reset controller driver looks fine, just two questions below.
>
>> ---
>>
>> (no changes since v1)
>>
>> drivers/soc/mediatek/mtk-mmsys.c | 69 ++++++++++++++++++++++++++++++++
>> drivers/soc/mediatek/mtk-mmsys.h | 2 +
>> 2 files changed, 71 insertions(+)
>>
>> diff --git a/drivers/soc/mediatek/mtk-mmsys.c b/drivers/soc/mediatek/mtk-mmsys.c
>> index e681029fe804..6ac4deff0164 100644
>> --- a/drivers/soc/mediatek/mtk-mmsys.c
>> +++ b/drivers/soc/mediatek/mtk-mmsys.c
> [...]
>> @@ -91,6 +95,59 @@ void mtk_mmsys_ddp_disconnect(struct device *dev,
> [...]
>> +static int mtk_mmsys_reset(struct reset_controller_dev *rcdev, unsigned long id)
>> +{
>> + int ret;
>> +
>> + ret = mtk_mmsys_reset_assert(rcdev, id);
>> + if (ret)
>> + return ret;
>> +
>> + usleep_range(1000, 1100);
>
> Is this known to be enough for all IP cores that can be reset by this
> controller?
>

This time is copied from the downstream kernel, so, tbh, I am not totally sure
is enough or needed. Let me try to reach the Mediatek people for if they can
answer this.


>> + return mtk_mmsys_reset_deassert(rcdev, id);
>> +}
>> +
>> +static const struct reset_control_ops mtk_mmsys_reset_ops = {
>> + .assert = mtk_mmsys_reset_assert,
>> + .deassert = mtk_mmsys_reset_deassert,
>> + .reset = mtk_mmsys_reset,
>> +};
>> +
>> static int mtk_mmsys_probe(struct platform_device *pdev)
>> {
>> struct device *dev = &pdev->dev;
>> @@ -111,6 +168,18 @@ static int mtk_mmsys_probe(struct platform_device *pdev)
>> return ret;
>> }
>>
>> + spin_lock_init(&mmsys->lock);
>> +
>> + mmsys->rcdev.owner = THIS_MODULE;
>> + mmsys->rcdev.nr_resets = 32;
>
> Are all bits in the MMSYS_SW0_RST_B register individual reset controls?

Yes, all are individual reset controls, mostly related to display but not all
(i.e dsi, dpi ...)

Thanks,
Enric

>
> regards
> Philipp
>

\
 
 \ /
  Last update: 2021-07-20 19:12    [W:0.997 / U:0.776 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site