Changeset 89344d85 in mainline for arch/amd64/src/asm_utils.S

Timestamp:

2005-09-03T00:19:23Z (20 years ago)

Author:

Ondrej Palkovsky <ondrap@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

36b209a

Parents:

e4a6dda

Message:

Changes, that were needed to make it work on Bochs.

• We CAN use the NX bit in paging tables, but we have

to initialize the NXE bit in EFER register first.

File:

• arch/amd64/src/asm_utils.S (modified) (4 diffs)

arch/amd64/src/asm_utils.S

@@ -40 +40 @@
 .global interrupt_handlers
 .global panic_printf
+.global cpuid
 
 panic_printf:
@@ -47 +48 @@
 .global has_cpuid
 .global rdtsc
-
-
+.global read_efer_flag
+.global set_efer_flag
+        
 ## Determine CPUID support
 #
@@ -71 +73 @@
         ret
 
+cpuid:
+        movq %rbx, %r10  # we have to preserve rbx across function calls
+
+        movl %edi,%eax  # load the command into %eax
+
+        cpuid   
+        movl %eax,0(%rsi)
+        movl %ebx,4(%rsi)
+        movl %ecx,8(%rsi)
+        movl %edx,12(%rsi)
+
+        movq %r10, %rbx
+        ret
 
 rdtsc:
@@ -76 +91 @@
         rdtsc
         ret
-        
+
+set_efer_flag:
+        movq $0xc0000080, %rcx
+        rdmsr
+        btsl %edi, %eax
+        wrmsr
+        ret
+        
+read_efer_flag: 
+        movq $0xc0000080, %rcx
+        rdmsr
+        ret             
 
 # Push all general purpose registers on stack except %rbp, %rsp