From 1dccbd1a382aa57719e4e0432b3bd6a03a888507 Mon Sep 17 00:00:00 2001
From: "Czajkowski, Maciej" <maciej.czajkowski@intel.com>
Date: Sat, 10 Sep 2022 02:10:55 +0800
Subject: [PATCH] MdeModulePkg/AhciPei: Fix MMIO base assignment

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4041

There is a mistake in getting MMIO base using PciDevicePpi that
can lead to the data corruption.

Cc: Hao A Wu <hao.a.wu@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Signed-off-by: Maciej Czajkowski <maciej.czajkowski@intel.com>
Reviewed-by: Hao A Wu <hao.a.wu@intel.com>
---
 MdeModulePkg/Bus/Ata/AhciPei/AhciPei.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/MdeModulePkg/Bus/Ata/AhciPei/AhciPei.c b/MdeModulePkg/Bus/Ata/AhciPei/AhciPei.c
index 98dd732a40..e33d863d2a 100644
--- a/MdeModulePkg/Bus/Ata/AhciPei/AhciPei.c
+++ b/MdeModulePkg/Bus/Ata/AhciPei/AhciPei.c
@@ -405,7 +405,7 @@ AtaAhciInitPrivateDataFromPciDevice (
 {
   EFI_STATUS                Status;
   PCI_TYPE00                PciData;
-  UINTN                     MmioBase;
+  UINT32                    MmioBase;
   EFI_DEVICE_PATH_PROTOCOL  *DevicePath;
   UINTN                     DevicePathLength;
   UINT64                    EnabledPciAttributes;
@@ -454,13 +454,15 @@ AtaAhciInitPrivateDataFromPciDevice (
                                   &PciDevice->PciIo,
                                   EfiPciIoWidthUint32,
                                   0x24,
-                                  sizeof (UINTN),
+                                  1,
                                   &MmioBase
                                   );
   if (EFI_ERROR (Status)) {
     return EFI_UNSUPPORTED;
   }
 
+  MmioBase &= 0xFFFFFFF0;
+
   DevicePathLength = GetDevicePathSize (PciDevice->DevicePath);
   DevicePath       = PciDevice->DevicePath;