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Diffstat (limited to 'MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.asm')
-rw-r--r--MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.asm95
1 files changed, 95 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.asm b/MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.asm
new file mode 100644
index 000000000000..84c8053fc4ed
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+++ b/MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.asm
@@ -0,0 +1,95 @@
+;------------------------------------------------------------------------------
+;
+; Copyright (c) 2009-2013, ARM Ltd. All rights reserved.
+; SPDX-License-Identifier: BSD-2-Clause-Patent
+;
+;------------------------------------------------------------------------------
+
+ EXPORT SetJump
+ EXPORT InternalLongJump
+ AREA BaseLib_LowLevel, CODE, READONLY
+
+#define GPR_LAYOUT \
+ REG_PAIR (x19, x20, #0); \
+ REG_PAIR (x21, x22, #16); \
+ REG_PAIR (x23, x24, #32); \
+ REG_PAIR (x25, x26, #48); \
+ REG_PAIR (x27, x28, #64); \
+ REG_PAIR (x29, x30, #80);/*FP, LR*/ \
+ REG_ONE (x16, #96) /*IP0*/
+
+#define FPR_LAYOUT \
+ REG_PAIR ( d8, d9, #112); \
+ REG_PAIR (d10, d11, #128); \
+ REG_PAIR (d12, d13, #144); \
+ REG_PAIR (d14, d15, #160);
+
+;/**
+; Saves the current CPU context that can be restored with a call to LongJump() and returns 0.#
+;
+; Saves the current CPU context in the buffer specified by JumpBuffer and returns 0. The initial
+; call to SetJump() must always return 0. Subsequent calls to LongJump() cause a non-zero
+; value to be returned by SetJump().
+;
+; If JumpBuffer is NULL, then ASSERT().
+; For IPF CPUs, if JumpBuffer is not aligned on a 16-byte boundary, then ASSERT().
+;
+; @param JumpBuffer A pointer to CPU context buffer.
+;
+;**/
+;
+;UINTN
+;EFIAPI
+;SetJump (
+; IN BASE_LIBRARY_JUMP_BUFFER *JumpBuffer // X0
+; );
+;
+SetJump
+ mov x16, sp // use IP0 so save SP
+#define REG_PAIR(REG1, REG2, OFFS) stp REG1, REG2, [x0, OFFS]
+#define REG_ONE(REG1, OFFS) str REG1, [x0, OFFS]
+ GPR_LAYOUT
+ FPR_LAYOUT
+#undef REG_PAIR
+#undef REG_ONE
+ mov w0, #0
+ ret
+
+;/**
+; Restores the CPU context that was saved with SetJump().#
+;
+; Restores the CPU context from the buffer specified by JumpBuffer.
+; This function never returns to the caller.
+; Instead is resumes execution based on the state of JumpBuffer.
+;
+; @param JumpBuffer A pointer to CPU context buffer.
+; @param Value The value to return when the SetJump() context is restored.
+;
+;**/
+;VOID
+;EFIAPI
+;InternalLongJump (
+; IN BASE_LIBRARY_JUMP_BUFFER *JumpBuffer, // X0
+; IN UINTN Value // X1
+; );
+;
+InternalLongJump
+#define REG_PAIR(REG1, REG2, OFFS) ldp REG1, REG2, [x0, OFFS]
+#define REG_ONE(REG1, OFFS) ldr REG1, [x0, OFFS]
+ GPR_LAYOUT
+ FPR_LAYOUT
+#undef REG_PAIR
+#undef REG_ONE
+ mov sp, x16
+ cmp w1, #0
+ mov w0, #1
+ beq exit
+ mov w0, w1
+exit
+ // use br not ret, as ret is guaranteed to mispredict
+ br x30
+
+ASM_FUNCTION_REMOVE_IF_UNREFERENCED
+
+ END
+