On Wed, Apr 3, 2024 at 4:45 PM Rick Wertenbroek rick.wertenbroek@gmail.com wrote:
Remove wrong mask on subsys_vendor_id. Both the Vendor ID and Subsystem Vendor ID are u16 variables and are written to a u32 register of the controller. The Subsystem Vendor ID was always 0 because the u16 value was masked incorrectly with GENMASK(31,16) resulting in all lower 16 bits being set to 0 prior to the shift.
Remove both masks as they are unnecessary and set the register correctly i.e., the lower 16-bits are the Vendor ID and the upper 16-bits are the Subsystem Vendor ID.
This is documented in the RK3399 TRM section 17.6.7.1.17
Fixes: cf590b078391 ("PCI: rockchip: Add EP driver for Rockchip PCIe controller") Signed-off-by: Rick Wertenbroek rick.wertenbroek@gmail.com Cc: stable@vger.kernel.org
drivers/pci/controller/pcie-rockchip-ep.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-)
diff --git a/drivers/pci/controller/pcie-rockchip-ep.c b/drivers/pci/controller/pcie-rockchip-ep.c index c9046e97a1d2..37d4bcb8bd5b 100644 --- a/drivers/pci/controller/pcie-rockchip-ep.c +++ b/drivers/pci/controller/pcie-rockchip-ep.c @@ -98,10 +98,9 @@ static int rockchip_pcie_ep_write_header(struct pci_epc *epc, u8 fn, u8 vfn,
/* All functions share the same vendor ID with function 0 */ if (fn == 0) {
u32 vid_regs = (hdr->vendorid & GENMASK(15, 0)) |(hdr->subsys_vendor_id & GENMASK(31, 16)) << 16;rockchip_pcie_write(rockchip, vid_regs,
rockchip_pcie_write(rockchip,hdr->vendorid |hdr->subsys_vendor_id << 16, PCIE_CORE_CONFIG_VENDOR); }-- 2.25.1
This patch was tested on linux next-20240403.
The PCI endpoint test function was used and an arbitrary value e.g., 0x1234 was written to /sys/kernel/config/pci_ep/functions/pci_epf_test/pci_epf_test.0/subsys_vendor_id
This value was then verified with lspci -x / lspci -v on a host computer acting as PCI root complex.
Cheers, Rick