Re: [Qemu-devel] [PATCH v3 1/3] pcie aer: verify if AER functionality is available

[Alex Williamson <alex.williamson@redhat.com>]

On Thu, 23 Mar 2017 17:09:21 +0800
Cao jin <caoj.fnst@cn.fujitsu.com> wrote:

> For devices which support AER function, verify it can work or not in the
> system:
> 1. AER capable device is a PCIe device, it can't be plugged into PCI bus
> 2. If root port doesn't support AER, then there is no need to expose the
>    AER capability
> 
> Signed-off-by: Dou Liyang <douly.fnst@cn.fujitsu.com>
> Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
> ---
>  hw/pci/pcie_aer.c | 28 ++++++++++++++++++++++++++++
>  1 file changed, 28 insertions(+)
> 
> diff --git a/hw/pci/pcie_aer.c b/hw/pci/pcie_aer.c
> index daf1f65..a2e9818 100644
> --- a/hw/pci/pcie_aer.c
> +++ b/hw/pci/pcie_aer.c
> @@ -100,6 +100,34 @@ static void aer_log_clear_all_err(PCIEAERLog *aer_log)
>  int pcie_aer_init(PCIDevice *dev, uint8_t cap_ver, uint16_t offset,
>                    uint16_t size, Error **errp)
>  {
> +    PCIDevice *parent_dev;
> +    uint8_t type;
> +    uint8_t parent_type;
> +
> +    /* Topology test: see if there is need to expose AER cap */
> +    type = pcie_cap_get_type(dev);
> +    parent_dev = pci_bridge_get_device(dev->bus);
> +    while (parent_dev) {
> +        parent_type = pcie_cap_get_type(parent_dev);
> +
> +        if (type == PCI_EXP_TYPE_ENDPOINT &&
> +                (parent_type != PCI_EXP_TYPE_ROOT_PORT &&
> +                 parent_type != PCI_EXP_TYPE_DOWNSTREAM)) {
> +            error_setg(errp, "Parent device is not a PCIe component");
> +            return -ENOTSUP;
> +        }
> +        
> +        if (parent_type == PCI_EXP_TYPE_ROOT_PORT) {
> +            if (!parent_dev->exp.aer_cap)
> +            {

Curly brace at the end of the previous line.

> +                error_setg(errp, "Root port does not support AER");
> +                return -ENOTSUP;
> +            }
> +        }
> +
> +        parent_dev = pci_bridge_get_device(parent_dev->bus);
> +    }
> +
>      pcie_add_capability(dev, PCI_EXT_CAP_ID_ERR, cap_ver,
>                          offset, size);
>      dev->exp.aer_cap = offset;

This patch makes existing configurations including PCIe root ports,
upstream ports, downstream ports, and e1000e fail if they do not meet
this new configuration requirement.