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From: Songyang Li <leesongyang@outlook.com>
To: helgaas@kernel.org
Cc: bhelgaas@google.com,
	leesongyang@outlook.com,
	linux-kernel@vger.kernel.org,
	linux-pci@vger.kernel.org
Subject: Re: [PATCH] PCI: Cancel compilation restrictions on function pcie_clear_device_status
Date: Sat, 15 Jun 2024 11:13:07 +0800
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On Wed, 12 Jun 2024 15:14:32 -0500, Bjorn Helgaas wrote:
> I think all current any callers of pcie_clear_device_status() are also
> under CONFIG_PCIEAER, so I don't think this fixes a current problem.
> 
> As you point out, it might make sense to use
> pcie_clear_device_status() even without AER, but I think we should
> include this change at the time when we add such a use.
> 
> If I'm missing a use with the current kernel, let me know.


As far as I know, some PCIe device drivers, for example,
[net/ethernet/broadcom/tg3.c],[net/ethernet/atheros/atl1c/atl1c_main.c],
which use the following code to clear the device status register,
pcie_capability_write_word(tp->pdev, PCI_EXP_DEVSTA,
                PCI_EXP_DEVSTA_CED |
                PCI_EXP_DEVSTA_NFED |
                PCI_EXP_DEVSTA_FED |
                PCI_EXP_DEVSTA_URD);
I think it may be more suitable to export the pcie_clear_device_status()
for use in the driver code.
Thanks,

Songyang Li