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authorBrijesh Singh <brijesh.singh@amd.com>2017-07-06 09:29:03 -0400
committerJordan Justen <jordan.l.justen@intel.com>2017-07-10 21:17:28 -0700
commit5feae25392ce52b936c34d2ea9f3f006bd37472c (patch)
tree257a44c910d00e202bcf91bb5eb18d6bbe7dbb0e /OvmfPkg/Library/QemuFwCfgLib
parent6264abc29eeabbb2dc756f815ff779d3105518f3 (diff)
downloadedk2-5feae25392ce52b936c34d2ea9f3f006bd37472c.tar.gz
edk2-5feae25392ce52b936c34d2ea9f3f006bd37472c.tar.bz2
edk2-5feae25392ce52b936c34d2ea9f3f006bd37472c.zip
OvmfPkg/QemuFwCfgLib: Implement SEV internal functions for PEI phase
Cc: Jordan Justen <jordan.l.justen@intel.com> Cc: Laszlo Ersek <lersek@redhat.com> Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
Diffstat (limited to 'OvmfPkg/Library/QemuFwCfgLib')
-rw-r--r--OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPei.c72
-rw-r--r--OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPeiLib.inf1
2 files changed, 71 insertions, 2 deletions
diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPei.c b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPei.c
index ac05f4c347..40f89c3b53 100644
--- a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPei.c
+++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPei.c
@@ -4,6 +4,7 @@
Copyright (C) 2013, Red Hat, Inc.
Copyright (c) 2011 - 2013, Intel Corporation. All rights reserved.<BR>
+ Copyright (c) 2017, Advanced Micro Devices. All rights reserved.<BR>
This program and the accompanying materials are licensed and made available
under the terms and conditions of the BSD License which accompanies this
@@ -14,8 +15,10 @@
WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
**/
+#include <Library/BaseLib.h>
#include <Library/DebugLib.h>
#include <Library/QemuFwCfgLib.h>
+#include <Library/MemEncryptSevLib.h>
#include "QemuFwCfgLibInternal.h"
@@ -76,8 +79,18 @@ QemuFwCfgInitialize (
if ((Revision & FW_CFG_F_DMA) == 0) {
DEBUG ((DEBUG_INFO, "QemuFwCfg interface (IO Port) is supported.\n"));
} else {
- mQemuFwCfgDmaSupported = TRUE;
- DEBUG ((DEBUG_INFO, "QemuFwCfg interface (DMA) is supported.\n"));
+ //
+ // If SEV is enabled then we do not support DMA operations in PEI phase.
+ // This is mainly because DMA in SEV guest requires using bounce buffer
+ // (which need to allocate dynamic memory and allocating a PAGE size'd
+ // buffer can be challenge in PEI phase)
+ //
+ if (InternalQemuFwCfgSevIsEnabled ()) {
+ DEBUG ((DEBUG_INFO, "SEV: QemuFwCfg fallback to IO Port interface.\n"));
+ } else {
+ mQemuFwCfgDmaSupported = TRUE;
+ DEBUG ((DEBUG_INFO, "QemuFwCfg interface (DMA) is supported.\n"));
+ }
}
return RETURN_SUCCESS;
}
@@ -114,3 +127,58 @@ InternalQemuFwCfgDmaIsAvailable (
{
return mQemuFwCfgDmaSupported;
}
+
+/**
+
+ Returns a boolean indicating whether SEV is enabled
+
+ @retval TRUE SEV is enabled
+ @retval FALSE SEV is disabled
+**/
+BOOLEAN
+InternalQemuFwCfgSevIsEnabled (
+ VOID
+ )
+{
+ return MemEncryptSevIsEnabled ();
+}
+
+/**
+ Allocate a bounce buffer for SEV DMA.
+
+ @param[in] NumPage Number of pages.
+ @param[out] Buffer Allocated DMA Buffer pointer
+
+**/
+VOID
+InternalQemuFwCfgSevDmaAllocateBuffer (
+ OUT VOID **Buffer,
+ IN UINT32 NumPages
+ )
+{
+ //
+ // We should never reach here
+ //
+ ASSERT (FALSE);
+ CpuDeadLoop ();
+}
+
+/**
+ Free the DMA buffer allocated using InternalQemuFwCfgSevDmaAllocateBuffer
+
+ @param[in] NumPage Number of pages.
+ @param[in] Buffer DMA Buffer pointer
+
+**/
+VOID
+InternalQemuFwCfgSevDmaFreeBuffer (
+ IN VOID *Buffer,
+ IN UINT32 NumPages
+ )
+{
+ //
+ // We should never reach here
+ //
+ ASSERT (FALSE);
+ CpuDeadLoop ();
+}
diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPeiLib.inf b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPeiLib.inf
index 47e23b97ec..7e51c3f160 100644
--- a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPeiLib.inf
+++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgPeiLib.inf
@@ -47,4 +47,5 @@
DebugLib
IoLib
MemoryAllocationLib
+ MemEncryptSevLib