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authorAnthony PERARD <anthony.perard@citrix.com>2014-10-29 06:49:55 +0000
committerjljusten <jljusten@Edk2>2014-10-29 06:49:55 +0000
commitbba9d16231fe9f7d67e0530e720530d91a88ad73 (patch)
treea5ea457e342d026ecac745eb64b55afe63422b32 /OvmfPkg/XenBusDxe/X64
parent12a16f2d1c610942a3420c86e7a3c6bcc7a6eedf (diff)
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OvmfPkg/XenBusDxe: Add InterlockedCompareExchange16.
This patch is inspired by InterlockedCompareExchange32 from the BaseSynchronizationLib. The function will be used in the "OvmfPkg/XenBusDxe: Add Grant Table functions" patch. Change in V3: - Implement both .S and .asm, to get rid of GCC specific asm. - Implement 32bit part of the assembly Change in V2: - Add intel compilation code MSFT code is not compied over because I don't know how it works. Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Anthony PERARD <anthony.perard@citrix.com> Reviewed-by: Jordan Justen <jordan.l.justen@intel.com> git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16263 6f19259b-4bc3-4df7-8a09-765794883524
Diffstat (limited to 'OvmfPkg/XenBusDxe/X64')
-rw-r--r--OvmfPkg/XenBusDxe/X64/InterlockedCompareExchange16.S13
-rw-r--r--OvmfPkg/XenBusDxe/X64/InterlockedCompareExchange16.asm41
2 files changed, 54 insertions, 0 deletions
diff --git a/OvmfPkg/XenBusDxe/X64/InterlockedCompareExchange16.S b/OvmfPkg/XenBusDxe/X64/InterlockedCompareExchange16.S
new file mode 100644
index 0000000000..23e08f3f6e
--- /dev/null
+++ b/OvmfPkg/XenBusDxe/X64/InterlockedCompareExchange16.S
@@ -0,0 +1,13 @@
+# UINT16
+# EFIAPI
+# InternalSyncCompareExchange16 (
+# IN volatile UINT16 *Value,
+# IN UINT16 CompareValue,
+# IN UINT16 ExchangeValue
+# );
+ASM_GLOBAL ASM_PFX(InternalSyncCompareExchange16)
+ASM_PFX(InternalSyncCompareExchange16):
+ mov %edx, %eax
+ lock
+ cmpxchgw %r8w, (%rcx)
+ ret
diff --git a/OvmfPkg/XenBusDxe/X64/InterlockedCompareExchange16.asm b/OvmfPkg/XenBusDxe/X64/InterlockedCompareExchange16.asm
new file mode 100644
index 0000000000..b23e421abc
--- /dev/null
+++ b/OvmfPkg/XenBusDxe/X64/InterlockedCompareExchange16.asm
@@ -0,0 +1,41 @@
+;------------------------------------------------------------------------------
+;
+; Copyright (c) 2006, Intel Corporation. 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 distribution. The full text of the license may be found at
+; http://opensource.org/licenses/bsd-license.php.
+;
+; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+;
+; Module Name:
+;
+; InterlockedCompareExchange16.Asm
+;
+; Abstract:
+;
+; InterlockedCompareExchange16 function
+;
+; Notes:
+;
+;------------------------------------------------------------------------------
+
+ .code
+
+;------------------------------------------------------------------------------
+; UINT16
+; EFIAPI
+; InterlockedCompareExchange16 (
+; IN UINT16 *Value,
+; IN UINT16 CompareValue,
+; IN UINT16 ExchangeValue
+; );
+;------------------------------------------------------------------------------
+InternalSyncCompareExchange16 PROC
+ mov eax, edx
+ lock cmpxchg [rcx], r8w
+ ret
+InternalSyncCompareExchange16 ENDP
+
+ END