Re: [patch 04/16] I/O driver for 8250-compatible UARTs

From: Tom Rini
Date: Wed Aug 31 2005 - 16:24:23 EST


On Wed, Aug 31, 2005 at 10:03:34PM +0100, Russell King wrote:
> On Wed, Aug 31, 2005 at 01:10:39PM -0700, Tom Rini wrote:
> > On Wed, Aug 31, 2005 at 01:38:52PM -0600, Bjorn Helgaas wrote:
> > > On Monday 29 August 2005 10:09 am, Tom Rini wrote:
> > > > linux-2.6.13-trini/drivers/serial/kgdb_8250.c | 594 +++++++++++++++++++++
> > >
> > > The existing stuff in drivers/serial is named "8250_*"; is
> > > there a reason you're using "kgdb_8250" rather than "8250_kgdb"?
> >
> > All the other kgdb stuff tends to be prefixed, not suffixed. But I
> > don't really care either way.
>
> I'd prefer it was 8250_kgdb.c actually - that keeps it along side the
> other 8250 files.

Will do.

> > > > + switch (CURRENTPORT.iotype) {
> > > > + case UPIO_MEM:
> > > > + if (CURRENTPORT.mapbase)
> > > > + kgdb8250_needs_request_mem_region = 1;
> > > > + if (CURRENTPORT.flags & UPF_IOREMAP) {
> > > > + CURRENTPORT.membase = ioport_map(CURRENTPORT.mapbase,
> > > > + 8 << KGDB8250_REG_SHIFT);
> > >
> > > Shouldn't this be ioremap instead of ioport_map?
> >
> > If I remember right from the testing, no. Or if my memory is wrong and
> > that's retorihcal, sure.
>
> ioport_map() is supposed to be used to map the IO range for the ioread/
> iowrite operations. IOW, it takes something compatible with inb() and
> friends and converts it to something compatible with ioread8() and
> friends.
>
> It does not take a MMIO cookie, so the code above appears to be
> conceptually wrong.
>

So it's luck (or another mapping I didn't see elsewhere) that this
worked, and it should still be ioremap(...) to use with ioread/write8
later on in the code?

--
Tom Rini
http://gate.crashing.org/~trini/
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