On Thu, Jun 30, 2016 at 06:53:09PM +0800, Yongji Xie wrote:
>We should not disable memory decoding when we reassign alignment
>in pci_reassigndev_resource_alignment(). It's meaningless and
>have some side effect. For example, some fixup functions such as
>quirk_e100_interrupt() read PCI_COMMAND_MEMORY to know whether
>the devices has been initialized by the firmware or not. If we
>disable memory decoding here, these functions will get a wrong
>information that the devices was not initialized by the firmware
>which may cause a wrong fixup. Besides, disabling memory decoding
>may also break some devices that need to have memory decoding
>always-on during probing.
>
It seems the changelog isn't correct enough if it's talking about
below check in code:
if (!(command & PCI_COMMAND_MEMORY) || !pci_resource_start(dev, 0))
return;
>Signed-off-by: Yongji Xie <xyj...@linux.vnet.ibm.com>
>---
> drivers/pci/pci.c | 8 +-------
> 1 file changed, 1 insertion(+), 7 deletions(-)
>
>diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
>index 6ae02de..6241cfc 100644
>--- a/drivers/pci/pci.c
>+++ b/drivers/pci/pci.c
>@@ -4820,7 +4820,6 @@ void pci_reassigndev_resource_alignment(struct pci_dev
>*dev)
> int i;
> struct resource *r;
> resource_size_t align, size;
>- u16 command;
>
> /* We should never try to reassign VF's alignment */
> if (dev->is_virtfn)
>@@ -4838,12 +4837,7 @@ void pci_reassigndev_resource_alignment(struct pci_dev
>*dev)
> return;
> }
>
>- dev_info(&dev->dev,
>- "Disabling memory decoding and releasing memory resources.\n");
>- pci_read_config_word(dev, PCI_COMMAND, &command);
>- command &= ~PCI_COMMAND_MEMORY;
>- pci_write_config_word(dev, PCI_COMMAND, command);
>-
>+ dev_info(&dev->dev, "Releasing memory resources.\n");
Is there a problem you found with PCI_COMMAND removed? If so, could you
please share more details, thanks.
> for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) {
> r = &dev->resource[i];
> if (!(r->flags & IORESOURCE_MEM))
Thanks,
Gavin
