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

[Blue Swirl]

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.
> > 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