Re: [PATCH 00/14] arm64: dts: imx8mp: correct pad settings

From: Peng Fan (OSS)
Date: Sat Jun 25 2022 - 08:41:36 EST




在 2022/6/22 14:31, Rasmus Villemoes 写道:
On 22/06/2022 08.13, Peng Fan (OSS) wrote:
From: Peng Fan <peng.fan@xxxxxxx>

i.MX8MP iomux pad BIT3 and BIT0 are reserved bits. Writing 1 to the
reserved bit will be ignored and reading will still return 0. Although
function not broken with reserved bits set, we should not set reserved
bits.
Thank you, these have really been bugging my while trying to bring up an
imx8mp-based board and adding the right pinmux settings - not knowing
whether there was some undocumented effect from including one of those
bits has led me astray more than once.

One question: E.g. in patch 11, you change the setting from 0x49 to
0x40, which is of course exactly what the patch description says. But
when bit 8 (PE) is not set, is there any effect from either setting of
bit 6 (PUE)? Not that I suggest changing to 0x00, but I'm just curious.

Set PE/PUE, it depends on board design or whether need it. Because the previous settings not set them, I not set them also, just
not touch the reserved bits.

THanks,
Peng.


For the series:

Reviewed-by: Rasmus Villemoes <rasmus.villemoes@xxxxxxxxx>