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

From: Sinan Kaya
Date: Thu May 31 2018 - 11:38:24 EST


On 5/31/2018 11:29 AM, Alex_Gagniuc@xxxxxxxxxxxx wrote:
> On 5/31/2018 10:28 AM, Sinan Kaya wrote:
>> 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.
>
> Hmm. I couldn't find them.

https://lkml.org/lkml/2018/3/30/553

are you working on linux-next?

>
> Alex
>
>


--
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.