From 713db6f6d3a3212270fd12ba5c47e986b36dbc39 Mon Sep 17 00:00:00 2001
From: Stephen Carlson <stcarlso@linux.microsoft.com>
Date: Fri, 10 Mar 2023 11:07:14 -0800
Subject: [PATCH] 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>
---
 drivers/misc/swap_case.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/misc/swap_case.c b/drivers/misc/swap_case.c
index 7093ad1cd4..ee5c12bd0a 100644
--- 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;
-- 
2.39.5