Re: [PATCH 2/2] PCI: Avoid bus reset for Cavium cn8xxx root ports.

From: Auger Eric
Date: Tue May 16 2017 - 16:14:57 EST


Hi,

On 16/05/2017 02:17, David Daney wrote:
> Root ports of cn8xxx do not function after bus reset when used with
> some e1000e and LSI HBA devices. Add a quirk to prevent bus reset on
> these root ports.
I understand the bus reset would work along with a variety of other
child devices. I guess there is no way to be more accurate and forbid
the bus reset only when incompatible child devices are found?
>
> Signed-off-by: David Daney <david.daney@xxxxxxxxxx>
> ---
> drivers/pci/quirks.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> index 085fb78..02cd847 100644
> --- a/drivers/pci/quirks.c
> +++ b/drivers/pci/quirks.c
> @@ -3347,6 +3347,14 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATHEROS, 0x0032, quirk_no_bus_reset);
> DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATHEROS, 0x003c, quirk_no_bus_reset);
> DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_ATHEROS, 0x0033, quirk_no_bus_reset);
>
> +/*
> + * Root port on some Cavium CN8xxx chips do not successfully complete
> + * a bus reset when used with certain types child devices. Config
s/types /types of
Thanks

Eric
> + * space access to the child may quit responding. Flag the root port
> + * as not supporting bus reset.
> + */
> +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_CAVIUM, 0xa100, quirk_no_bus_reset);
> +
> static void quirk_no_pm_reset(struct pci_dev *dev)
> {
> /*
>