Re: [OpenBIOS] [PATCH] pci: fix BAR setup

[Artyom Tarasenko]

On Thu, Apr 19, 2012 at 10:04 PM, Blue Swirl  wrote:
> On Thu, Apr 19, 2012 at 19:06, Artyom Tarasenko  wrote:
> > On Sun, Mar 11, 2012 at 11:59 AM, Blue Swirl  wrote:
> > > A change in QEMU on how PCI bridges are setup revealed
> > > a bug in OpenBIOS PCI setup. On Sparc64, the BARs just
> > > happened to get somewhat correct values by accident before
> > > the commit but not after the change.
> > >
> > > Don't use arch->io_base for PCI I/O port BARs.
> > >
> > > Fix Sparc64 PCI memory base.
> >
> > Could it be that the ranges property needs to be adjusted to look as
> > it did before the patch?
> >
> > This patch breaks HelenOS-0.4.3/sparc boot. But if I modify the ranges
> > property to the old value, HelenOS boots.
> >
> > 0 > cd /pci@1fe,0  ok
> > 0 > .properties
> > [...]
> > ranges                    -- 54 : 00 00 00 00 00 00 00 00 00 00 00 00
> > 00 00 01 fe 01 00 00 00 00 00 00 00 02 00 00 00 01 00 00 00 00 00 00
> > 00 00 00 00 00 00 00 01 fe 02 00 00 00 00 00 00 00 00 01 00 00 02 00
> > 00 00 00 00 00 00 00 10 00 00 00 00 01 ff 00 00 00 00 00 00 00 00 10
> > 00 00 00
> >
> > Not sure about the best formatting. If I reformat it like this:
> >
> > 00000000 00000000 00000000 000001fe 01000000 00000000 02000000
> > 01000000 00000000 00000000 000001fe 02000000 00000000 00010000
> > 02000000 00000000 00100000 000001ff 00000000 00000000 10000000
> >                               ^^^^ this one (the third) used to be 0
>
> On an Ultra-5 this should be
> 00000000.00000000.00000000.000001fe.01000000.00000000.01000000.
> 01000000.00000000.00000000.000001fe.02000000.00000000.01000000.
> 02000000.00000000.00000000.000001ff.00000000.00000001.00000000.
> 03000000.00000000.00000000.000001ff.00000000.00000001.00000000
>
> http://git.kernel.org/?p=linux/kernel/git/davem/prtconfs.git;a=blob;f=ultra5...
>
> I guess the problem is that the properties are added by finding the
> host bridge in the PCI bus (which btw isn't so nice), so we use the
> pci_mem_base. Using pci_mem_base = 0 would probably fix the BAR, but
> then VGA would get in the way. Probably something more complex is
> needed.

Hmm. Complicated. What is actually the meaning of this property? Don't
we need the values ourselves?
If these are just BARs, can't we pass the configuration from qemu?
> > > Signed-off-by: Blue Swirl
> > >
> > > I removed the bridge setup code, it's not really valid for Sparc64 APB
> > > bridges anyway and currently no devices exist behind the bridges (but
> > > that's where they really should be).
> > >
> > > Tested Sparc64 and PPC.
> > >
> > > arch/sparc64/openbios.c |    2 +-
> > >  drivers/pci.c           |   11 +++++++++--
> > >  2 files changed, 10 insertions(+), 3 deletions(-)
> > >
> > > diff --git a/arch/sparc64/openbios.c b/arch/sparc64/openbios.c
> > > index ac709fe..ab32a8f 100644
> > > --- a/arch/sparc64/openbios.c
> > > +++ b/arch/sparc64/openbios.c
> > > @@ -64,7 +64,7 @@ static const struct hwdef hwdefs[] = {
> > >             .cfg_base = APB_SPECIAL_BASE,
> > >             .cfg_len = 0x2000000,
> > >             .host_mem_base = APB_MEM_BASE,
> > > .pci_mem_base = 0,
> > > .pci_mem_base = 0x100000, /* avoid VGA at 0xa0000 */
> > >
> > > .mem_len = 0x10000000,
> > >             .io_base = APB_SPECIAL_BASE + 0x2000000ULL, // PCI Bus I/O space
> > >             .io_len = 0x10000,
> > > diff --git a/drivers/pci.c b/drivers/pci.c
> > > index f8c6414..e270a73 100644
> > > --- a/drivers/pci.c
> > > +++ b/drivers/pci.c
> > > @@ -931,6 +931,7 @@ static void ob_pci_configure_bar(pci_addr addr,
> > > pci_config_t *config,
> > >
> > > if ((*p_omask & 0x0000000f) == 0x4) {
> > >                 /* 64 bits memory mapping */
> > > PCI_DPRINTF("Skipping 64 bit BARs for %s\n", config->path);
> > >
> > > return;
> > >         }
> > >
> > > @@ -966,11 +967,17 @@ static void ob_pci_configure_bar(pci_addr addr,
> > > pci_config_t *config,
> > >                 size = min_align;
> > >         reloc = (reloc + size -1) & ~(size - 1);
> > >         if (*io_base == base) {
> > > PCI_DPRINTF("changing io_base from 0x%lx to 0x%x\n",
> > > *io_base, reloc + size);
> > >
> > > *io_base = reloc + size;
> > > reloc -= arch->io_base;
> > >
> > > } else {
> > > PCI_DPRINTF("changing mem_base from 0x%lx to 0x%x\n",
> > > *mem_base, reloc + size);
> > >
> > > *mem_base = reloc + size;
> > >         }
> > > PCI_DPRINTF("Configuring BARs for %s: reloc 0x%x omask 0x%x "
> > > "io_base 0x%lx mem_base 0x%lx size 0x%x\n",
> > > config->path, reloc, *p_omask, *io_base, *mem_base, size);
> > >
> > > pci_config_write32(addr, config_addr, reloc | *p_omask);
> > >         config->assigned[reg] = reloc | *p_omask;
> > >  }
> > > @@ -1260,7 +1267,7 @@ int ob_pci_init(void)
> > >     mem_base = arch->pci_mem_base;
> > >     /* I/O ports under 0x400 are used by devices mapped at fixed
> > >        location. */
> > > io_base = arch->io_base + 0x400;
> > > io_base = 0x400;
> > >
> > > bus = 0;
> >
> > solaris/sparc under qemu blog: http://tyom.blogspot.com/search/label/qemu