On Mon, 28 Dec 2020 15:05:10 +0100
Nadeem Athani <nadeem@xxxxxxxxxxx> wrote:
> +static void cdns_pcie_retrain(struct cdns_pcie *pcie)
Shouldn't this propagate a return value ?
> +{
> + u32 lnk_cap_sls, pcie_cap_off = CDNS_PCIE_RP_CAP_OFFSET;
> + u16 lnk_stat, lnk_ctl;
> +
> + /*
> + * Set retrain bit if current speed is 2.5 GB/s,
> + * but the PCIe root port support is > 2.5 GB/s.
> + */
> +
> + lnk_cap_sls = cdns_pcie_readl(pcie, (CDNS_PCIE_RP_BASE + pcie_cap_off +
> + PCI_EXP_LNKCAP));
> + if ((lnk_cap_sls & PCI_EXP_LNKCAP_SLS) <= PCI_EXP_LNKCAP_SLS_2_5GB)
> + return;
> +
> + lnk_stat = cdns_pcie_rp_readw(pcie, pcie_cap_off + PCI_EXP_LNKSTA);
> + if ((lnk_stat & PCI_EXP_LNKSTA_CLS) == PCI_EXP_LNKSTA_CLS_2_5GB) {
> + lnk_ctl = cdns_pcie_rp_readw(pcie,
> + pcie_cap_off + PCI_EXP_LNKCTL);
> + lnk_ctl |= PCI_EXP_LNKCTL_RL;
> + cdns_pcie_rp_writew(pcie, pcie_cap_off + PCI_EXP_LNKCTL,
> + lnk_ctl);
> +
> + if (cdns_pcie_host_wait_for_link(pcie))
> + return;
Here, shouldn't you return the status of
cdns_pcie_host_wait_for_link(), to propagate whether the PCIe link
indeed came up after the retrain ?
Thomas
--
Thomas Petazzoni, CTO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com
