RE: [PATCH 1/5 V2] PCI: define a function to check and wait till port finish DPC handling

[Zhao, Haifeng]

Yep, I am think the same question, is there any other files better to put this function ?
How  about pci.c ?

Thanks,
Ethan

-----Original Message-----
From: Christoph Hellwig <hch@xxxxxxxxxxxxx> 
Sent: Sunday, September 27, 2020 2:24 PM
To: Zhao, Haifeng <haifeng.zhao@xxxxxxxxx>
Cc: bhelgaas@xxxxxxxxxx; oohall@xxxxxxxxx; ruscur@xxxxxxxxxx; lukas@xxxxxxxxx; andriy.shevchenko@xxxxxxxxxxxxxxx; stuart.w.hayes@xxxxxxxxx; mr.nuke.me@xxxxxxxxx; mika.westerberg@xxxxxxxxxxxxxxx; linux-pci@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Jia, Pei P <pei.p.jia@xxxxxxxxx>; ashok.raj@xxxxxxxxxxxxxxx; Kuppuswamy, Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxx>
Subject: Re: [PATCH 1/5 V2] PCI: define a function to check and wait till port finish DPC handling

> +#ifdef CONFIG_PCIE_DPC
> +static inline bool pci_wait_port_outdpc(struct pci_dev *pdev) {
> +	u16 cap = pdev->dpc_cap, status;
> +	u16 loop = 0;
> +
> +	if (!cap) {
> +		pci_WARN_ONCE(pdev, !cap, "No DPC capability initiated\n");
> +		return false;
> +	}
> +	pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status);
> +	pci_dbg(pdev, "DPC status %x, cap %x\n", status, cap);
> +	while (status & PCI_EXP_DPC_STATUS_TRIGGER && loop < 100) {
> +		msleep(10);
> +		loop++;
> +		pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status);
> +	}
> +	if (!(status & PCI_EXP_DPC_STATUS_TRIGGER)) {
> +		pci_dbg(pdev, "Out of DPC %x, cost %d ms\n", status, loop*10);
> +		return true;
> +	}
> +	pci_dbg(pdev, "Timeout to wait port out of DPC status\n");
> +	return false;
> +}

I don't think that there is any good reason to have this as an inline function.