[RFC PATCH v2 1/2] PCI: rockchip-host: Retry link training on failure without PERST#

[Bjorn Helgaas]

On Tue, Jun 10, 2025 at 01:37:12PM -0300, Geraldo Nascimento wrote:
> After almost 30 days of battling with RK3399 buggy PCIe on my Rock Pi
> N10 through trial-and-error debugging, I finally got positive results
> with enumeration on the PCI bus for both a Realtek 8111E NIC and a
> Samsung PM981a SSD.

> +static int rockchip_pcie_set_vpcie(struct rockchip_pcie *rockchip)
> +{
> +	struct device *dev = rockchip->dev;
> +	int err;
> +
> +	if (!IS_ERR(rockchip->vpcie12v)) {
> +		err = regulator_enable(rockchip->vpcie12v);
> +		if (err) {
> +			dev_err(dev, "fail to enable vpcie12v regulator\n");
> +			goto err_out;
> +		}
> +	}
> +
> +	if (!IS_ERR(rockchip->vpcie3v3)) {
> +		err = regulator_enable(rockchip->vpcie3v3);
> +		if (err) {
> +			dev_err(dev, "fail to enable vpcie3v3 regulator\n");
> +			goto err_disable_12v;
> +		}
> +	}
> +
> +	err = regulator_enable(rockchip->vpcie1v8);
> +	if (err) {
> +		dev_err(dev, "fail to enable vpcie1v8 regulator\n");
> +		goto err_disable_3v3;
> +	}
> +
> +	err = regulator_enable(rockchip->vpcie0v9);
> +	if (err) {
> +		dev_err(dev, "fail to enable vpcie0v9 regulator\n");
> +		goto err_disable_1v8;
> +	}
> +
> +	return 0;
> +
> +err_disable_1v8:
> +	regulator_disable(rockchip->vpcie1v8);
> +err_disable_3v3:
> +	if (!IS_ERR(rockchip->vpcie3v3))
> +		regulator_disable(rockchip->vpcie3v3);
> +err_disable_12v:
> +	if (!IS_ERR(rockchip->vpcie12v))
> +		regulator_disable(rockchip->vpcie12v);
> +err_out:
> +	return err;
> +}

This *looks* like it could be strictly a move of
rockchip_pcie_set_vpcie(), without changing it at all.

If that's the case, please make the move a separate patch so it's more
obvious what the interesting changes that actually make a difference
are.