bb81bf6215
The offset of PCIe Capability Header for AMD and HYGON NTB is 0x64,
but the macro which named "AMD_LINK_STATUS_OFFSET" is defined as 0x68.
It is offset of Device Capabilities Reg rather than Link Control Reg.
This code trigger an error in get link statsus:
cat /sys/kernel/debug/ntb_hw_amd/0000:43:00.1/info
LNK STA - 0x8fa1
Link Status - Up
Link Speed - PCI-E Gen 0
Link Width - x0
This patch use pcie_capability_read_dword to get link status.
After fix this issue, we can get link status accurately:
cat /sys/kernel/debug/ntb_hw_amd/0000:43:00.1/info
LNK STA - 0x11030042
Link Status - Up
Link Speed - PCI-E Gen 3
Link Width - x16
Fixes: a1b3695820aa4 ("NTB: Add support for AMD PCI-Express Non-Transparent Bridge")
Signed-off-by: Jiasen Lin <linjiasen@hygon.cn>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.