In current code there is no cache flush after initializing the scratchpad buffer array with the scratchpad buffer pointers. This leads to a failure of the "slot enable" command on the rpi4 board (Broadcom STB PCIe controller + VL805 USB hub) - the very first TRB transfer on the command ring fails and there is a timeout while waiting for the command completion event. After adding the missing cache flush everything seems to be working as expected.
Signed-off-by: Sylwester Nawrocki s.nawrocki@samsung.com --- drivers/usb/host/xhci-mem.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c index 93450ee..729bdc3 100644 --- a/drivers/usb/host/xhci-mem.c +++ b/drivers/usb/host/xhci-mem.c @@ -393,6 +393,9 @@ static int xhci_scratchpad_alloc(struct xhci_ctrl *ctrl) scratchpad->sp_array[i] = cpu_to_le64(ptr); }
+ xhci_flush_cache((uintptr_t)scratchpad->sp_array, + sizeof(u64) * num_sp); + return 0;
fail_sp3: