Re: [PATCH][2.6] PCI Scan all functions

[Andrew Morton <akpm@osdl.org>]

Greg KH <greg@kroah.com> wrote:
>
> On Tue, Jan 27, 2004 at 10:55:01AM -0600, Jake Moilanen wrote:
> > There are some arch, like PPC64, that need to be able to scan all the
> > PCI functions.  The problem comes in on a logically partitioned system
> > where function 0 on a PCI-PCI bridge is assigned to one partition and
> > say function 2 is assiged to another partition.  On the second
> > partition, it would appear that function 0 does not exist, but function
> > 2 does.  If all the functions are not scanned, everything under function
> > 2 would not be detected.
> 
> Heh, I think the PPC64 people need to get together and all talk about
> this, as I just got a different patch, that solves much the same problem
> from John Rose (it's on the linuxppc64 mailing list.)
> 
> Can you two get together and not patch the same section of code to do
> the same thing in different ways?

While we're on the topic, what's with the below patch?  I've had it in -mm
for ages but apparently there's some disagreement over it.



From: Anton Blanchard <anton@samba.org>

We have IO BARs on ppc64 machines that begin at address 0. The current
pci probe code will ignore anything that starts at 0. Remove these checks.



---

 drivers/pci/probe.c |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

diff -puN drivers/pci/probe.c~ppc64-bar-0-fix drivers/pci/probe.c
--- 25/drivers/pci/probe.c~ppc64-bar-0-fix	2004-01-13 23:23:18.000000000 -0800
+++ 25-akpm/drivers/pci/probe.c	2004-01-13 23:23:18.000000000 -0800
@@ -176,7 +176,7 @@ void __devinit pci_read_bridge_bases(str
 		limit |= (io_limit_hi << 16);
 	}
 
-	if (base && base <= limit) {
+	if (base <= limit) {
 		res->flags = (io_base_lo & PCI_IO_RANGE_TYPE_MASK) | IORESOURCE_IO;
 		res->start = base;
 		res->end = limit + 0xfff;
@@ -187,7 +187,7 @@ void __devinit pci_read_bridge_bases(str
 	pci_read_config_word(dev, PCI_MEMORY_LIMIT, &mem_limit_lo);
 	base = (mem_base_lo & PCI_MEMORY_RANGE_MASK) << 16;
 	limit = (mem_limit_lo & PCI_MEMORY_RANGE_MASK) << 16;
-	if (base && base <= limit) {
+	if (base <= limit) {
 		res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM;
 		res->start = base;
 		res->end = limit + 0xfffff;
@@ -213,7 +213,7 @@ void __devinit pci_read_bridge_bases(str
 		}
 #endif
 	}
-	if (base && base <= limit) {
+	if (base <= limit) {
 		res->flags = (mem_base_lo & PCI_MEMORY_RANGE_TYPE_MASK) | IORESOURCE_MEM | IORESOURCE_PREFETCH;
 		res->start = base;
 		res->end = limit + 0xfffff;

_