Changeset b52da8d7 in mainline for arch/ia32

Timestamp:

2005-08-29T11:57:26Z (20 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

c245372b

Parents:

229d5fc1

Message:

Add some comments to IA-32 src/boot/boot.S and src/smp.S.

Make the boot stack start on page boundary.
This is required by get_stack_base().

Define 'THE' macro.

Implement preemption_disable() and preemption_enable().

Add memory barrier macros.
IA-32 macros need support for older processors.
Non IA-32 macros are dummy.

Reduction of many #include paths.

Location:

arch/ia32

Files:

• include/asm.h (modified) (1 diff)
• include/barrier.h (modified) (1 diff)
• src/boot/boot.S (modified) (3 diffs)
• src/mm/frame.c (modified) (1 diff)
• src/smp/ap.S (modified) (2 diffs)

arch/ia32/include/asm.h

@@ -32 +32 @@
 #include <arch/types.h>
 #include <typedefs.h>
-#include <mm/page.h>
+#include <config.h>
 #include <synch/spinlock.h>
 #include <arch/boot/memmap.h>

arch/ia32/include/barrier.h

@@ -44 +44 @@
 #define CS_LEAVE_BARRIER()      __asm__ volatile ("" ::: "memory")
 
+#define memory_barrier()        __asm__ volatile ("mfence\n" ::: "memory")
+#define read_barrier()          __asm__ volatile ("sfence\n" ::: "memory")
+#define write_barrier()         __asm__ volatile ("lfence\n" ::: "memory")
+
 #endif

arch/ia32/src/boot/boot.S

@@ -48 +48 @@
         call memmap_arch_init
         
-        lgdt gdtr
+        lgdt gdtr                       # initialize Global Descriptor Table register
+        lidt idtr                       # initialize Interrupt Descriptor Table register
+        
         movl %cr0,%eax
         orl $0x1,%eax
-        movl %eax,%cr0
+        movl %eax,%cr0                  # switch to protected mode
         jmpl $8,$meeting_point
 meeting_point:
@@ -63 +65 @@
         movw %ax,%ss
 
-        lidt idtr
-
-        call map_kernel
+        call map_kernel                 # map kernel and turn paging on
 
         movl $_hardcoded_ktext_size, hardcoded_ktext_size
@@ -95 +95 @@
         movl %eax, %cr3
         
-        # turn on paging
+        # turn paging on
         movl %cr0, %ebx
         orl $(1<<31), %ebx

arch/ia32/src/mm/frame.c

@@ -35 +35 @@
 #include <print.h>
 
-/*
- * TODO: use the memory map obtained from BIOS
- */
 void frame_arch_init(void)
 {

arch/ia32/src/smp/ap.S

@@ -51 +51 @@
         movw %ax,%ds
 
-        lgdt gdtr
+        lgdt gdtr                       # initialize Global Descriptor Table register
+        lidt idtr                       # initialize Interrupt Descriptor Table register
+        
         movl %cr0,%eax
         orl $1,%eax
-        movl %eax,%cr0
+        movl %eax,%cr0                  # switch to protected mode
         jmpl $KTEXT,$jump_to_kernel
 jump_to_kernel:
@@ -66 +68 @@
         subl $0x80000000,%esp           # KA2PA(ctx.sp)
 
-        lidt idtr
-
-        call map_kernel
+        call map_kernel                 # map kernel and turn paging on
 
         jmpl $KTEXT,$main_ap