On Wed, Oct 04, 2023 at 06:17:50PM PDT, Andrew Jeffery wrote:
On Wed, 2023-10-04 at 00:16 -0700, Zev Weiss wrote:
Previously we've generally assumed that the defaults in the hardware
strapping register are in fact appropriate for the system and thus
have avoided making any changes to its contents (with the exception of
the bits controlling the GPIO passthrough feature).
Unfortunately, on some platforms corrections from software are
required as the hardware strapping is simply incorrect for the system
(such as the SPI1 interface being configured for passthrough mode when
master mode is in fact the only useful configuration for it). We thus
remove the checks preventing changes to the strap register so that the
pinctrl subsystem can be used for such corrections.
So the strapping for the SPI1 configuration seems to be prone to
(copy/paste?) mistakes. Is there evidence that motivates dropping all
the protection instead of poking a hole for SPI1 like we did for the
passthrough GPIOs?
I'm still a little attached to the policy that software should be
beholden to the strapping, and to try to mitigate software mistakes
given the smattering of bits required to drive the Aspeed pinmux.
I have no idea what else might be lurking out there so I took a broader
(perhaps overly heavy-handed) approach, but the SPI1 mode bits are the
only ones I've personally encountered being strapped wrong, so sure, I'd
be fine with just extending the "hole-punch" a bit to add those bits.
I'll send a v2 doing that shortly.
Thanks,
Zev
