Changeset bd5f3b7 in mainline for kernel/arch/ia32/src/boot/boot.S

Timestamp:

2011-08-21T13:07:35Z (13 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

00aece0, f1a9e87

Parents:

86a34d3e (diff), a6480d5 (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge mainline changes.

File:

• kernel/arch/ia32/src/boot/boot.S (modified) (10 diffs)

kernel/arch/ia32/src/boot/boot.S

@@ -97 +97 @@
         pm_status $status_prot
         
+#include "vesa_prot.inc"
+        
+#ifndef PROCESSOR_i486
+        
+        pm_status $status_prot2
+        
         movl $(INTEL_CPUID_LEVEL), %eax
         cpuid
@@ -105 +111 @@
         cpuid
         bt $(INTEL_PSE), %edx
-        jc pse_supported
+        jnc pse_unsupported
+                
+                /* Map kernel and turn paging on */
+                pm_status $status_pse
+                call map_kernel_pse
+                jmp stack_init
+        
+#endif /* PROCESSOR_i486 */
         
         pse_unsupported:
                 
-                pm_error $err_pse
-        
-        pse_supported:
-        
-#include "vesa_prot.inc"
-        
-        /* Map kernel and turn paging on */
-        call map_kernel
+                /* Map kernel and turn paging on */
+                pm_status $status_non_pse
+                call map_kernel
+        
+        stack_init:
         
         /* Create the first stack frame */
@@ -122 +132 @@
         movl %esp, %ebp
         
-        pm2_status $status_prot2
+        pm2_status $status_prot3
         
         /* Call arch_pre_main(grub_eax, grub_ebx) */
@@ -140 +150 @@
                 jmp hlt0
 
-/** Setup mapping for the kernel.
+/** Setup mapping for the kernel (PSE variant)
  *
  * Setup mapping for both the unmapped and mapped sections
@@ -146 +156 @@
  *
  */
-.global map_kernel
-map_kernel:
+.global map_kernel_pse
+map_kernel_pse:
+        /* Paging features */
         movl %cr4, %ecx
         orl $(1 << 4), %ecx      /* PSE on */
@@ -158 +169 @@
         xorl %ebx, %ebx
         
-        floop:
+        floop_pse:
                 movl $((1 << 7) | (1 << 1) | (1 << 0)), %eax
                 orl %ebx, %eax
@@ -169 +180 @@
                 incl %ecx
                 cmpl $512, %ecx
-                jl floop
+                jl floop_pse
         
         movl %esi, %cr3
@@ -177 +188 @@
         movl %ebx, %cr0
         ret
+
+/** Setup mapping for the kernel (non-PSE variant).
+ *
+ * Setup mapping for both the unmapped and mapped sections
+ * of the kernel. For simplicity, we map the entire 4G space.
+ *
+ */
+.global map_kernel
+map_kernel:
+        /* Paging features */
+        movl %cr4, %ecx
+        andl $(~(1 << 5)), %ecx  /* PAE off */
+        movl %ecx, %cr4
+        
+        call calc_kernel_end
+        call find_mem_for_pt
+        
+        mov kernel_end, %esi
+        mov free_area, %ecx
+        
+        cmpl %esi, %ecx
+        jbe use_kernel_end
+                
+                mov %ecx, %esi
+                
+                /* Align address down to 4k */
+                andl $(~4095), %esi
+                
+        use_kernel_end:
+                
+                /* Align address to 4k */
+                addl $4095, %esi
+                andl $(~4095), %esi
+                
+                /* Allocate space for page tables */
+                movl %esi, pt_loc
+                movl $ballocs, %edi
+                andl $0x7fffffff, %edi
+                
+                movl %esi, (%edi)
+                addl $4, %edi
+                movl $(2 * 1024 * 1024), (%edi)
+                
+                /* Fill page tables */
+                xorl %ecx, %ecx
+                xorl %ebx, %ebx
+                
+                floop_pt:
+                        movl $((1 << 1) | (1 << 0)), %eax
+                        orl %ebx, %eax
+                        movl %eax, (%esi, %ecx, 4)
+                        addl $(4 * 1024), %ebx
+                        
+                        incl %ecx
+                        cmpl $(512 * 1024), %ecx
+                        
+                        jl floop_pt
+                
+                /* Fill page directory */
+                movl $(page_directory + 0), %esi
+                movl $(page_directory + 2048), %edi
+                xorl %ecx, %ecx
+                movl pt_loc, %ebx
+                
+                floop:
+                        movl $((1 << 1) | (1 << 0)), %eax
+                        orl %ebx, %eax
+                        
+                        /* Mapping 0x00000000 + %ecx * 4M => 0x00000000 + %ecx * 4M */
+                        movl %eax, (%esi, %ecx, 4)
+                        
+                        /* Mapping 0x80000000 + %ecx * 4M => 0x00000000 + %ecx * 4M */
+                        movl %eax, (%edi, %ecx, 4)
+                        addl $(4 * 1024), %ebx
+                        
+                        incl %ecx
+                        cmpl $512, %ecx
+                        
+                        jl floop
+                
+                movl %esi, %cr3
+                
+                movl %cr0, %ebx
+                orl $(1 << 31), %ebx  /* paging on */
+                movl %ebx, %cr0
+                
+                ret
+
+/** Calculate unmapped address of the end of the kernel. */
+calc_kernel_end:
+        movl $hardcoded_load_address, %edi
+        andl $0x7fffffff, %edi
+        movl (%edi), %esi
+        andl $0x7fffffff, %esi
+        
+        movl $hardcoded_ktext_size, %edi
+        andl $0x7fffffff, %edi
+        addl (%edi), %esi
+        andl $0x7fffffff, %esi
+        
+        movl $hardcoded_kdata_size, %edi
+        andl $0x7fffffff, %edi
+        addl (%edi), %esi
+        andl $0x7fffffff, %esi
+        movl %esi, kernel_end
+        
+        ret
+
+/** Find free 2M (+4k for alignment) region where to store page tables */
+find_mem_for_pt:
+        /* Check if multiboot info is present */
+        cmpl $MULTIBOOT_LOADER_MAGIC, grub_eax
+        je check_multiboot_map
+                
+                ret
+        
+        check_multiboot_map:
+                
+                /* Copy address of the multiboot info to ebx */
+                movl grub_ebx, %ebx
+                
+                /* Check if memory map flag is present */
+                movl (%ebx), %edx
+                andl $(1 << 6), %edx
+                jnz use_multiboot_map
+                        
+                        ret
+                
+        use_multiboot_map:
+                
+                /* Copy address of the memory map to edx */
+                movl 48(%ebx), %edx
+                movl %edx, %ecx
+                
+                addl 44(%ebx), %ecx
+                
+                /* Find a free region at least 2M in size */
+                check_memmap_loop:
+                        
+                        /* Is this a free region? */
+                        cmp $1, 20(%edx)
+                        jnz next_region
+                        
+                        /* Check size */
+                        cmp $0, 16(%edx)
+                        jnz next_region
+                        
+                        cmpl $(2 * 1024 * 1024 + 4 * 1024), 12(%edx)
+                        jbe next_region
+                        
+                        cmp $0, 8(%edx)
+                        jz found_region
+                
+                next_region:
+                        
+                        cmp %ecx, %edx
+                        jbe next_region_do
+                        
+                                ret
+                
+                next_region_do:
+                        
+                        addl (%edx), %edx
+                        addl $4, %edx
+                        jmp check_memmap_loop
+                        
+                found_region:
+                        
+                        /* Use end of the found region */
+                        mov 4(%edx), %ecx
+                        add 12(%edx), %ecx
+                        sub $(2 * 1024 * 1024), %ecx
+                        mov %ecx, free_area
+                        
+                        ret
 
 /** Print string to EGA display (in light red) and halt.
@@ -521 +707 @@
 grub_eax:
         .long 0
-
 grub_ebx:
         .long 0
 
-err_pse:
-        .asciz "Page Size Extension not supported. System halted."
+pt_loc:
+        .long 0
+kernel_end:
+        .long 0
+free_area:
+        .long 0
 
 status_prot:
         .asciz "[prot] "
+status_pse:
+        .asciz "[pse] "
+status_non_pse:
+        .asciz "[non_pse] "
 status_vesa_copy:
         .asciz "[vesa_copy] "
@@ -538 +731 @@
 status_prot2:
         .asciz "[prot2] "
+status_prot3:
+        .asciz "[prot3] "
 status_main:
         .asciz "[main] "