2009-07-16 00:28:25

by dann frazier

Subject: [PATCH] [x86] pci: Get rid of magic number in AMD bus discovery

The number 4 is hardcoded in a couple of loops.
Use the already-defined PCI_ROOT_NR macro instead.

Signed-off-by: dann frazier <[email protected]>
---
arch/x86/pci/amd_bus.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/pci/amd_bus.c b/arch/x86/pci/amd_bus.c
index 3ffa10d..feb3e09 100644
--- a/arch/x86/pci/amd_bus.c
+++ b/arch/x86/pci/amd_bus.c
@@ -332,7 +332,7 @@ static int __init early_fill_mp_bus_info(void)
return 0;

pci_root_num = 0;
- for (i = 0; i < 4; i++) {
+ for (i = 0; i < PCI_ROOT_NR; i++) {
int min_bus;
int max_bus;
reg = read_pci_config(bus, slot, 1, 0xe0 + (i << 2));
@@ -368,7 +368,7 @@ static int __init early_fill_mp_bus_info(void)
memset(range, 0, sizeof(range));
range[0].end = 0xffff;
/* io port resource */
- for (i = 0; i < 4; i++) {
+ for (i = 0; i < PCI_ROOT_NR; i++) {
reg = read_pci_config(bus, slot, 1, 0xc0 + (i << 3));
if (!(reg & 3))
continue;
--
1.6.3.3

2009-07-16 10:10:01

by Yinghai Lu

Subject: Re: [PATCH] [x86] pci: Get rid of magic number in AMD bus discovery

dann frazier wrote:
> The number 4 is hardcoded in a couple of loops.
> Use the already-defined PCI_ROOT_NR macro instead.
>
> Signed-off-by: dann frazier <[email protected]>
> ---
> arch/x86/pci/amd_bus.c | 4 ++--
> 1 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/pci/amd_bus.c b/arch/x86/pci/amd_bus.c
> index 3ffa10d..feb3e09 100644
> --- a/arch/x86/pci/amd_bus.c
> +++ b/arch/x86/pci/amd_bus.c
> @@ -332,7 +332,7 @@ static int __init early_fill_mp_bus_info(void)
> return 0;
>
> pci_root_num = 0;
> - for (i = 0; i < 4; i++) {
> + for (i = 0; i < PCI_ROOT_NR; i++) {
> int min_bus;
> int max_bus;
> reg = read_pci_config(bus, slot, 1, 0xe0 + (i << 2));
> @@ -368,7 +368,7 @@ static int __init early_fill_mp_bus_info(void)
> memset(range, 0, sizeof(range));
> range[0].end = 0xffff;
> /* io port resource */
> - for (i = 0; i < 4; i++) {
> + for (i = 0; i < PCI_ROOT_NR; i++) {
> reg = read_pci_config(bus, slot, 1, 0xc0 + (i << 3));
> if (!(reg & 3))
> continue;

please don't do that.

how about
/* mmio resource */
for (i = 0; i < 8; i++) {

those value is decided by HW...

YH

2009-07-16 14:58:07

by dann frazier

Subject: Re: [PATCH] [x86] pci: Get rid of magic number in AMD bus discovery

On Thu, Jul 16, 2009 at 03:09:22AM -0700, Yinghai Lu wrote:
> dann frazier wrote:
> > The number 4 is hardcoded in a couple of loops.
> > Use the already-defined PCI_ROOT_NR macro instead.
> >
> > Signed-off-by: dann frazier <[email protected]>
> > ---
> > arch/x86/pci/amd_bus.c | 4 ++--
> > 1 files changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/x86/pci/amd_bus.c b/arch/x86/pci/amd_bus.c
> > index 3ffa10d..feb3e09 100644
> > --- a/arch/x86/pci/amd_bus.c
> > +++ b/arch/x86/pci/amd_bus.c
> > @@ -332,7 +332,7 @@ static int __init early_fill_mp_bus_info(void)
> > return 0;
> >
> > pci_root_num = 0;
> > - for (i = 0; i < 4; i++) {
> > + for (i = 0; i < PCI_ROOT_NR; i++) {
> > int min_bus;
> > int max_bus;
> > reg = read_pci_config(bus, slot, 1, 0xe0 + (i << 2));
> > @@ -368,7 +368,7 @@ static int __init early_fill_mp_bus_info(void)
> > memset(range, 0, sizeof(range));
> > range[0].end = 0xffff;
> > /* io port resource */
> > - for (i = 0; i < 4; i++) {
> > + for (i = 0; i < PCI_ROOT_NR; i++) {
> > reg = read_pci_config(bus, slot, 1, 0xc0 + (i << 3));
> > if (!(reg & 3))
> > continue;
>
> please don't do that.
>
> how about
> /* mmio resource */
> for (i = 0; i < 8; i++) {
>
> those value is decided by HW...

Sorry, I don't follow.
My goal was just to remove the magic '4' number and replace it with a
macro instead - not to bump it up. PCI_ROOT_NR looked like the right
value (used in declaring the array we are indexing), but if not maybe
some other macro should be defined?

--
dann frazier