On 11/10, Lukas Wunner wrote:

On Mon, Oct 11, 2021 at 11:37:33PM +0530, Naveen Naidu wrote:

quoted

An MMIO read from a PCI device that doesn't exist or doesn't respond
causes a PCI error.  There's no real data to return to satisfy the
CPU read, so most hardware fabricates ~0 data.

Use RESPONSE_IS_PCI_ERROR() to check the response we get when we read
data from hardware.

Actually what happens is that PCI read transactions *time out*,
so the host controller fabricates a response.

Ah! yes. Now that I look at it, RESPONSE_IS_PCI_TIMEOUT() does indeed
seem like a better option to RESPONSE_IS_PCI_ERROR(), since it's more
specfic and depicts the actual condition. 

I'll wait for sometime and see if others have any objection/a better
name for the macro and then redo the patch with that.

Thank you very much for the review ^^ 

By contrast, a PCI *error* usually denotes an Uncorrectable or
Correctable Error as specified in section 6.2.2 of the PCIe Base Spec.

Thus something like RESPONSE_IS_PCI_TIMEOUT() or IS_PCI_TIMEOUT() would
probably be more appropriate.  I'll leave the exact bikeshed color for
others to decide. :-)

quoted

Signed-off-by: Naveen Naidu <redacted>
---
 drivers/pci/hotplug/pciehp_hpc.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

Acked-by: Lukas Wunner <lukas@wunner.de>

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