In D37981#1213421, @markj wrote:

In D37981#1210335, @avg wrote:

Totally belated, but would it make (have made) sense to split default behavior of reboot and reset commands?
I think that it would be more natural if reboot tried to do a reboot and reset just went for a reset (where implemented)?

I think that would make sense. In retrospect it's a bit silly that reboot and reset are aliases of each other, and both have the /s modifier.

Most likely, this same treatment should be applied to the similar cd_detect() function in sys/dev/sdhci/sdhci_fdt_gpio.c.

@imp any objection?

I have not succeeded in using this myself, but I have never tried too hard.

Committed. Forgot the DR tag.

Yes, please go ahead!

In D53119#1213368, @jrtc27 wrote:

The logic for removing this in the FDT is that, on Linux, the clock framework comes up early enough (or at least some early part of it) in order to be able to query the UART clock's frequency from the clock driver, whereas we don't do anything like that with clocks prior to newbus passes, so way too late for cninit.

Fix aw_spi.4

This prompted a secondary question of whether the x86 FDT experiment bits can be removed outright (sys/x86/x86/fdt_machdep.c).

You can use Fixes: 7393b267c6ce ("libc: Provide sub fp(s|g)etmask() implementations for RISC-V") in the commit message.

No objection from me on this one; @fuz your comments don't seem to be blockers, just possible refinements?

In D47807#1182659, @jhb wrote:

I'm trying to think of a case when the roundup would ever be correct. That is, there are two cases after the previous expression:

		sgsize = MIN(buflen, PAGE_SIZE - (curaddr & PAGE_MASK));

Either 1) sgsize == buflen, or 2) sgsize == PAGE_SIZE - (curaddr & PAGE_MASK)

Your patch turns case 1) into a no-op as it effectively undoes the roundup. Case 2) seems worse though. This means that we can now expand the S/G entry *off the end of the page* and randomly read/write data on the next physical page of RAM. There is no way that is correct. I wonder if this was meant to be a rounddown to keep segments a multiple of the alignment instead of a roundup? However, in that case you'd never finish a buffer whose size wasn't a multiple of the alignment.

Aha! See this part of the commit log from daf6545e6158f:

Now all contiguous regions returned from bus-dma will be aligned to the
alignment constraint and all but the last region are guaranteed to be
a multiple of the alignment in length.

I think if that is the desired behavior, then the correct fix instead is to replace the roundup2 line with this:

if (sgsize != buflen)
    sgsize = rounddown2(sgsize, dmat->common.alignment);

That will give the desired property. It should never have been a roundup2().

I've built and booted the driver.

In D47807#1098307, @markj wrote:

I'm sorry for the delayed follow-up. I'm trying to understand the purpose of the roundup. It appears to have been introduced by commit daf6545e6158f; the implication seems to be that some drivers depend on the property that "the relative alignment of two consecutive bytes in the I/O stream have a difference of 1 even if they are not physically contiguous."

I don't really understand why that property is important, but assuming so, I think your patch is probably the right thing to do.

Seems fine to me, with a couple tweaks needed.

Looks good to me, with some small nitpicks.