[PATCH] MdeModulePkg/SdMmcPciHcDxe: Fix DMA on SDHC v3 64-bit systems

["Cohen, Eugene" <eugene@hp.com>]

The SdMmcPciHcDriverBindingStart function was checking two
different capability bits in determining whether 64-bit DMA
modes were supported, one mode is defined in the SDHC version
3 specification (using 96-bit descriptors) and another is
defined in the SDHC version 4 specification (using 128-bit
descriptors).  Since the currently implementation of 64-bit
ADMA2 only supports the SDHC version 4 implementation it is
incorrect to check the V3 64-bit capability bit since this
will activate V4 ADMA2 on V3 controllers.

Cc: Hao Wu <hao.a.wu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eugene Cohen <eugene@hp.com>
---
MdeModulePkg/Bus/Pci/SdMmcPciHcDxe/SdMmcPciHcDxe.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/MdeModulePkg/Bus/Pci/SdMmcPciHcDxe/SdMmcPciHcDxe.c b/MdeModulePkg/Bus/Pci/SdMmcPciHcDxe/SdMmcPciHcDxe.c
index b474f8d..5bc91c5 100644
--- a/MdeModulePkg/Bus/Pci/SdMmcPciHcDxe/SdMmcPciHcDxe.c
+++ b/MdeModulePkg/Bus/Pci/SdMmcPciHcDxe/SdMmcPciHcDxe.c
@@ -666,8 +666,7 @@ SdMmcPciHcDriverBindingStart (
     // If any of the slots does not support 64b system bus
     // do not enable 64b DMA in the PCI layer.
     //
-    if (Private->Capability[Slot].SysBus64V3 == 0 &&
-        Private->Capability[Slot].SysBus64V4 == 0) {
+    if (Private->Capability[Slot].SysBus64V4 == 0) {
       Support64BitDma = FALSE;
     }

--
2.7.4