[PATCH 2.6.22-rc5] ahci: fix PORTS_IMPL override

[PATCH 2.6.22-rc5] ahci: fix PORTS_IMPL override

[Tejun Heo]

If PORTS_IMPL register is zero, ahci initialize it to full mask
corresponding to nr_ports in the CAP register.  hpriv->cap, which is
initialized at the end of the function, is incorrectly used as value
of CAP causing ahci to always override PORTS_IMPL to 0x1 if it's zero.
Fix it.

This fixes a bug where early ich6 ahci can only access the first port.

Signed-off-by: Tejun Heo <htejun@gmail.com>
---
 drivers/ata/ahci.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index 545f330..ca5229d 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -527,7 +527,7 @@ static void ahci_save_initial_config(struct pci_dev *pdev,
 
 	/* fixup zero port_map */
 	if (!port_map) {
-		port_map = (1 << ahci_nr_ports(hpriv->cap)) - 1;
+		port_map = (1 << ahci_nr_ports(cap)) - 1;
 		dev_printk(KERN_WARNING, &pdev->dev,
 			   "PORTS_IMPL is zero, forcing 0x%x\n", port_map);
 

Re: [PATCH 2.6.22-rc5] ahci: fix PORTS_IMPL override

[Jeff Garzik]

Tejun Heo wrote:
> If PORTS_IMPL register is zero, ahci initialize it to full mask
> corresponding to nr_ports in the CAP register.  hpriv->cap, which is
> initialized at the end of the function, is incorrectly used as value
> of CAP causing ahci to always override PORTS_IMPL to 0x1 if it's zero.
> Fix it.
> 
> This fixes a bug where early ich6 ahci can only access the first port.
> 
> Signed-off-by: Tejun Heo <htejun@gmail.com>
> ---
>  drivers/ata/ahci.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
> index 545f330..ca5229d 100644
> --- a/drivers/ata/ahci.c
> +++ b/drivers/ata/ahci.c
> @@ -527,7 +527,7 @@ static void ahci_save_initial_config(struct pci_dev *pdev,
>  
>  	/* fixup zero port_map */
>  	if (!port_map) {
> -		port_map = (1 << ahci_nr_ports(hpriv->cap)) - 1;
> +		port_map = (1 << ahci_nr_ports(cap)) - 1;
>  		dev_printk(KERN_WARNING, &pdev->dev,

good catch, applied