[PATCH v4 32/35] OvmfPkg: Introduce PcdXenGrantFrames

["Anthony PERARD" <anthony.perard@citrix.com>]

Introduce PcdXenGrantFrames to replace a define in XenBusDxe and allow
the same value to be used in a different module.

The reason for the number of page to be 4 doesn't exist anymore, so
simply remove the comment.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
---
 OvmfPkg/OvmfPkg.dec             | 3 +++
 OvmfPkg/XenBusDxe/XenBusDxe.inf | 2 ++
 OvmfPkg/XenBusDxe/XenBusDxe.h   | 1 +
 OvmfPkg/XenBusDxe/GrantTable.c  | 3 +--
 4 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/OvmfPkg/OvmfPkg.dec b/OvmfPkg/OvmfPkg.dec
index 04d5e29272..d5fee805ef 100644
--- a/OvmfPkg/OvmfPkg.dec
+++ b/OvmfPkg/OvmfPkg.dec
@@ -225,6 +225,9 @@ [PcdsFixedAtBuild]
   gUefiOvmfPkgTokenSpaceGuid.PcdXenPvhStartOfDayStructPtr|0x0|UINT32|0x17
   gUefiOvmfPkgTokenSpaceGuid.PcdXenPvhStartOfDayStructPtrSize|0x0|UINT32|0x32
 
+  ## Number of page frames to use for storing grant table entries.
+  gUefiOvmfPkgTokenSpaceGuid.PcdXenGrantFrames|4|UINT32|0x33
+
 [PcdsDynamic, PcdsDynamicEx]
   gUefiOvmfPkgTokenSpaceGuid.PcdEmuVariableEvent|0|UINT64|2
   gUefiOvmfPkgTokenSpaceGuid.PcdOvmfFlashVariablesEnable|FALSE|BOOLEAN|0x10
diff --git a/OvmfPkg/XenBusDxe/XenBusDxe.inf b/OvmfPkg/XenBusDxe/XenBusDxe.inf
index 86e0fb8224..0b78cd0af4 100644
--- a/OvmfPkg/XenBusDxe/XenBusDxe.inf
+++ b/OvmfPkg/XenBusDxe/XenBusDxe.inf
@@ -59,3 +59,5 @@ [Protocols]
   gXenBusProtocolGuid
   gXenIoProtocolGuid
 
+[FixedPcd]
+  gUefiOvmfPkgTokenSpaceGuid.PcdXenGrantFrames
diff --git a/OvmfPkg/XenBusDxe/XenBusDxe.h b/OvmfPkg/XenBusDxe/XenBusDxe.h
index 8510361bca..b1dcc3549c 100644
--- a/OvmfPkg/XenBusDxe/XenBusDxe.h
+++ b/OvmfPkg/XenBusDxe/XenBusDxe.h
@@ -22,6 +22,7 @@
 #include <Library/UefiLib.h>
 #include <Library/DevicePathLib.h>
 #include <Library/DebugLib.h>
+#include <Library/PcdLib.h>
 
 
 //
diff --git a/OvmfPkg/XenBusDxe/GrantTable.c b/OvmfPkg/XenBusDxe/GrantTable.c
index 6575e9b88c..1130404cd1 100644
--- a/OvmfPkg/XenBusDxe/GrantTable.c
+++ b/OvmfPkg/XenBusDxe/GrantTable.c
@@ -22,8 +22,7 @@
 
 #define NR_RESERVED_ENTRIES 8
 
-/* NR_GRANT_FRAMES must be less than or equal to that configured in Xen */
-#define NR_GRANT_FRAMES 4
+#define NR_GRANT_FRAMES (FixedPcdGet32 (PcdXenGrantFrames))
 #define NR_GRANT_ENTRIES (NR_GRANT_FRAMES * EFI_PAGE_SIZE / sizeof(grant_entry_v1_t))
 
 STATIC grant_entry_v1_t *GrantTable = NULL;
-- 
Anthony PERARD