Re: [PATCH v3 1/9] PCI/AER: Add pci_aer_clear_uncorrect_error_status() to PCI core

[Bjorn Helgaas <helgaas@kernel.org>]

On Wed, Sep 28, 2022 at 06:59:38PM +0800, Zhuo Chen wrote:
> In lpfc_aer_cleanup_state(), uncorrectable error status needs to be
> cleared, which can be done by calling pci_aer_clear_nonfatal_status()
> and pci_aer_clear_fatal_status(). Meanwhile they can be combined in
> one function (the same in dpc_process_error). So add
> pci_aer_clear_uncorrect_error_status() function to PCI core and
> export symbol to other modules which wants to use it.

Sorry for getting back to this so late.

Why does lpfc need this?  I think AER error status should be cleared
by the PCI core, not by individual drivers, so I really would rather
not add a new interface for drivers to use.

> Signed-off-by: Zhuo Chen <chenzhuo.1@bytedance.com>
> ---
>  drivers/pci/pcie/aer.c | 16 ++++++++++++++++
>  include/linux/aer.h    |  5 +++++
>  2 files changed, 21 insertions(+)
> 
> diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c
> index e2d8a74f83c3..4e637121be23 100644
> --- a/drivers/pci/pcie/aer.c
> +++ b/drivers/pci/pcie/aer.c
> @@ -286,6 +286,22 @@ void pci_aer_clear_fatal_status(struct pci_dev *dev)
>  		pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, status);
>  }
>  
> +int pci_aer_clear_uncorrect_error_status(struct pci_dev *dev)
> +{
> +	int aer = dev->aer_cap;
> +	u32 status;
> +
> +	if (!pcie_aer_is_native(dev))
> +		return -EIO;
> +
> +	pci_read_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, &status);
> +	if (status)
> +		pci_write_config_dword(dev, aer + PCI_ERR_UNCOR_STATUS, status);
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(pci_aer_clear_uncorrect_error_status);
> +
>  /**
>   * pci_aer_raw_clear_status - Clear AER error registers.
>   * @dev: the PCI device
> diff --git a/include/linux/aer.h b/include/linux/aer.h
> index 97f64ba1b34a..154690c278cb 100644
> --- a/include/linux/aer.h
> +++ b/include/linux/aer.h
> @@ -45,6 +45,7 @@ struct aer_capability_regs {
>  int pci_enable_pcie_error_reporting(struct pci_dev *dev);
>  int pci_disable_pcie_error_reporting(struct pci_dev *dev);
>  int pci_aer_clear_nonfatal_status(struct pci_dev *dev);
> +int pci_aer_clear_uncorrect_error_status(struct pci_dev *dev);
>  void pci_save_aer_state(struct pci_dev *dev);
>  void pci_restore_aer_state(struct pci_dev *dev);
>  #else
> @@ -60,6 +61,10 @@ static inline int pci_aer_clear_nonfatal_status(struct pci_dev *dev)
>  {
>  	return -EINVAL;
>  }
> +static inline int pci_aer_clear_uncorrect_error_status(struct pci_dev *dev)
> +{
> +	return -EINVAL;
> +}
>  static inline void pci_save_aer_state(struct pci_dev *dev) {}
>  static inline void pci_restore_aer_state(struct pci_dev *dev) {}
>  #endif
> -- 
> 2.30.1 (Apple Git-130)
>