Re: [PATCH] PCI: Check for PCIe downtraining conditions

From: Sinan Kaya
Date: Thu May 31 2018 - 11:28:19 EST


On 5/31/2018 11:05 AM, Alexandru Gagniuc wrote:
> +static void pcie_max_link_cap(struct pci_dev *dev, enum pci_bus_speed *speed,
> + enum pcie_link_width *width)
> +{
> + uint32_t lnkcap;
> +
> + pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, &lnkcap);
> +
> + *speed = pcie_link_speed[lnkcap & PCI_EXP_LNKCAP_SLS];
> + *width = (lnkcap & PCI_EXP_LNKCAP_MLW) >> PCI_EXP_LNKCAP_MLW_SHIFT;
> +}
> +
> +static void pcie_cur_link_sta(struct pci_dev *dev, enum pci_bus_speed *speed,
> + enum pcie_link_width *width)
> +{
> + uint16_t lnksta;
> +
> + pcie_capability_read_word(dev, PCI_EXP_LNKSTA, &lnksta);
> + *speed = pcie_link_speed[lnksta & PCI_EXP_LNKSTA_CLS];
> + *width = (lnksta & PCI_EXP_LNKSTA_NLW) >> PCI_EXP_LNKSTA_NLW_SHIFT;
> +}
> +
> +static const char *pcie_bus_speed_name(enum pci_bus_speed speed)
> +{
> + switch (speed) {
> + case PCIE_SPEED_2_5GT:
> + return "2.5 GT/s";
> + case PCIE_SPEED_5_0GT:
> + return "5.0 GT/s";
> + case PCIE_SPEED_8_0GT:
> + return "8.0 GT/s";
> + default:
> + return "unknown";
> + }
> +}

I thought Bjorn added some functions to retrieve this now.


--
Sinan Kaya
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.