From bf9c7d74eb0032000e3f5ef6be1c10162c774487 Mon Sep 17 00:00:00 2001
From: josh <josh@5b3e749e-e535-0410-8002-a9bb6afbdfca>
Date: Tue, 14 Jul 2009 13:31:08 +0000
Subject: [PATCH] added mm/stack module; initializing "permanent" stack for
 kernel use while paging, crashing when calling k_main() though...

git-svn-id: svn://anubis/hos/trunk@52 5b3e749e-e535-0410-8002-a9bb6afbdfca
---
 kernel/boot/boot.asm         |  4 +++-
 kernel/boot/k_bootstrap.cc   | 12 ++----------
 kernel/boot/k_main.cc        |  7 +++++++
 kernel/include/hos_defines.h |  2 ++
 kernel/lang/kio.cc           |  2 +-
 kernel/mm/stack.cc           | 14 ++++++++++++++
 kernel/mm/stack.h            |  7 +++++++
 7 files changed, 36 insertions(+), 12 deletions(-)
 create mode 100755 kernel/mm/stack.cc
 create mode 100755 kernel/mm/stack.h

diff --git a/kernel/boot/boot.asm b/kernel/boot/boot.asm
index 625ea65..88bfccc 100644
--- a/kernel/boot/boot.asm
+++ b/kernel/boot/boot.asm
@@ -12,6 +12,8 @@
 
 %define PAGE_SIZE                   0x1000              ; 4KB pages
 
+%define KERNEL_STACK_TOP            0xF0000000          ; permanent stack top
+
 ; Symbols from the linker
 extern _end, _bss
 
@@ -107,7 +109,7 @@ segmentation_disabled:
     mov     cx, 0x0700 + 'f'
     mov     [CONSOLE_MEMORY+160*8+5*2], cx
 
-    ; TODO: set up a stack!
+;    mov     esp, KERNEL_STACK_TOP
 ;    call    k_main
 
 idle_loop:
diff --git a/kernel/boot/k_bootstrap.cc b/kernel/boot/k_bootstrap.cc
index 0833eb9..a7c5464 100644
--- a/kernel/boot/k_bootstrap.cc
+++ b/kernel/boot/k_bootstrap.cc
@@ -4,6 +4,7 @@
 #include "multiboot.h"
 #include "k_early_panic.h"
 #include "mm/mm.h"
+#include "mm/stack.h"
 #include "lang/kio.h"
 
 #define DEBUG_LETTER(col,chr) *(u16_t *)(KERNEL_OFFSET + CONSOLE_MEMORY \
@@ -46,18 +47,9 @@ u32_t k_bootstrap(mb_info_t * mb_info, u32_t mb_magic)
      * before calling them.
      */
     mm_bootstrap();
+    stack_bootstrap();              /* after mm */
     kio_bootstrap();
 
-    kprintf("Hello from kprintf()! %d, %x, %u, %l\n", 42, 0xabcd0123, 0xFFFFFFFF, -1234567891234ll);
-
-#if 0
-    kprintf("d1: 0x%X\n", MAKE_DESCRIPTOR(0, 0xFFFFF, 1, 0, 1, 1));
-    kprintf("d2: 0x%X\n", MAKE_DESCRIPTOR(0, 0xFFFFF, 1, 0, 1, 0));
-
-    for (;;)
-        ;
-#endif
-
     return 0;
 }
 
diff --git a/kernel/boot/k_main.cc b/kernel/boot/k_main.cc
index 3aacb2a..2dd9f10 100644
--- a/kernel/boot/k_main.cc
+++ b/kernel/boot/k_main.cc
@@ -1,4 +1,11 @@
 
+#include "lang/kio.h"
+
+extern "C" {
+
 void k_main()
 {
+    kprintf("Hi from k_main()!\n");
 }
+
+} /* extern "C" */
diff --git a/kernel/include/hos_defines.h b/kernel/include/hos_defines.h
index c12f14a..5ce31f6 100644
--- a/kernel/include/hos_defines.h
+++ b/kernel/include/hos_defines.h
@@ -29,6 +29,8 @@ extern  u8_t    _end;
 #define KERNEL_VIRTUAL_ADDRESS  ((u32_t)KERNEL_CODE)
 #define KERNEL_SIZE             ((u32_t)(KERNEL_END - KERNEL_CODE))
 
+#define KERNEL_STACK_TOP        0xF0000000
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/kernel/lang/kio.cc b/kernel/lang/kio.cc
index 9c0374d..cd989c8 100644
--- a/kernel/lang/kio.cc
+++ b/kernel/lang/kio.cc
@@ -96,7 +96,7 @@ void kvprintf(const char * fmt, va_list args)
 
 void kputc(char c)
 {
-    u16_t * console_memory = (u16_t *) (CONSOLE_MEMORY + KERNEL_OFFSET);
+    u16_t * console_memory = (u16_t *) CONSOLE_MEMORY;
     console_memory += 80 * cursor_y + cursor_x;
     switch (c)
     {
diff --git a/kernel/mm/stack.cc b/kernel/mm/stack.cc
new file mode 100755
index 0000000..952019b
--- /dev/null
+++ b/kernel/mm/stack.cc
@@ -0,0 +1,14 @@
+
+#include "stack.h"
+#include "mm.h"
+#include "hos_defines.h"
+
+void stack_bootstrap()
+{
+    /*
+     * running from our temporary stack while segmentation is enabled,
+     * set up the "permanent" stack for use while paging
+     */
+    u32_t first_stack_page_base = mm_page_alloc();
+    mm_map(KERNEL_STACK_TOP - PAGE_SIZE, first_stack_page_base, 0, 1);
+}
diff --git a/kernel/mm/stack.h b/kernel/mm/stack.h
new file mode 100755
index 0000000..d649e80
--- /dev/null
+++ b/kernel/mm/stack.h
@@ -0,0 +1,7 @@
+
+#ifndef STACK_H
+#define STACK_H
+
+void stack_bootstrap();
+
+#endif