drivers: pci: sandbox: Add stub sandbox PCI MPS support

Reports the sandbox swapcase PCI Express device to support a 256 byte
Maximum Payload Size for MPS tuning tests.

Signed-off-by: Stephen Carlson <stcarlso@linux.microsoft.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

diff --git a/drivers/misc/swap_case.c b/drivers/misc/swap_case.c
index 7093ad1cd4fc642e953a715cc0015ecff94f2456..ee5c12bd0a426cb2e68deb3f89c93b33c309a060 100644 (file)
--- a/drivers/misc/swap_case.c
+++ b/drivers/misc/swap_case.c
@@ -165,6 +165,9 @@ static int sandbox_swap_case_read_config(const struct udevice *emul,
        case PCI_CAP_ID_EXP_OFFSET + PCI_CAP_LIST_NEXT:
                *valuep = PCI_CAP_ID_MSIX_OFFSET;
                break;
+       case PCI_CAP_ID_EXP_OFFSET + PCI_EXP_DEVCAP:
+               *valuep = PCI_EXP_DEVCAP_PAYLOAD_256B;
+               break;
        case PCI_CAP_ID_MSIX_OFFSET:
                if (sandbox_swap_case_use_ea(emul))
                        *valuep = (PCI_CAP_ID_EA_OFFSET << 8) | PCI_CAP_ID_MSIX;