amd64: barely boot into kernel code

1 files changed, 18 insertions, 0 deletions

diff --git a/src/kernel/arch/amd64/registers.h b/src/kernel/arch/amd64/registers.h
new file mode 100644
index 0000000..e365e2c
--- /dev/null
+++ b/src/kernel/arch/amd64/registers.h
@@ -0,0 +1,18 @@
+#pragma once
+#include <shared/types.h>
+#include <stdint.h>
+
+struct registers {
+	uint64_t edi, esi;
+	userptr_t ebp, esp;
+	uint64_t ebx, edx, ecx, eax;
+
+	userptr_t eip;
+} __attribute__((__packed__));
+
+// saves a return value according to the SysV ABI
+static inline uint64_t regs_savereturn(struct registers *regs, uint64_t value) {
+	regs->eax = value;
+	regs->edx = value >> 32; // TODO check ABI
+	return value;
+}