A bit flag, a bitfield is something else and should be avoided.

Ideally the values being written into the registers in sxiahci.c would
have their own defines instead of being a bunch of magic numbers as
well.  But that would be a seperate diff.

On Sat, Nov 22, 2014 at 10:04:06PM -0600, Edwin Amsler wrote:
> Okay, preferred method is the bitfield, not #ifdef.
> 
> I?ll get a patch done soon and submit.
> 
> On Nov 22, 2014, at 8:24 PM, Jonathan Gray <[email protected]> wrote:
> 
> > On Sat, Nov 22, 2014 at 02:06:48PM -0600, Edwin Amsler wrote:
> >> Hey there,
> >> 
> >> This e-mail is about design and custom arch-specific code.
> >> 
> >> I?m trying to author a patch from Bitrig to enable proper support for AHCI 
> >> in the SUNXI ARMv7 port. There?s a bit of a quirk in how SUNXI handles DMA 
> >> from what I understand of the patch. I think it may only affect the A10, 
> >> but that?s outside the scope of this e-mail.
> >> 
> >> The fix is a series of patches, but the first one is going to be the tough 
> >> since the change nestled inside ahci_port_start() in sys/dev/ic/ahci.c. 
> >> Here?s the web-view of the patch: (let me know if you need me to provide a 
> >> diff for readability)
> >> https://github.com/bitrig/bitrig/commit/6342a27bfe4dc590f8e266e370f54846a766a737
> >> 
> >> Now, I don?t care about the original author?s implementation choice, 
> >> everyone is justified in their own actions. What I want to know is what 
> >> needs to be done to increase the chances this will be committed by you 
> >> folks.
> >> 
> >> To be honest, I?d prefer to #ifdef the custom initialization based on 
> >> target platform and clean up the ahci_softc.sc_flags bit field. Is 
> >> everyone on board for that? Is there a better way?
> > 
> > The quirk bit should just be set in arch/armv7/sunxi/sxiahci.c
> > Change
> > sc->sc_flags |= AHCI_F_NO_PMP; /* XXX enough? */
> > to
> > sc->sc_flags |= AHCI_F_NO_PMP | AHCI_F_SUNXI_QUIRK;
> > 
> > That is how bitrig did it as well.
> > 
> > Some of the other register access changes in the sxiahci.c part of
> > https://github.com/bitrig/bitrig/commit/9859ab07da261ebb4f561ff2b5bc5802b63ac57c
> > may be of interest as well.

Reply via email to