diff options
Diffstat (limited to 'arch/x86/secondary.S')
| -rw-r--r-- | arch/x86/secondary.S | 28 |
1 files changed, 26 insertions, 2 deletions
diff --git a/arch/x86/secondary.S b/arch/x86/secondary.S index 7d795cfd3976..4fa6f4e17027 100644 --- a/arch/x86/secondary.S +++ b/arch/x86/secondary.S @@ -28,28 +28,52 @@ _secondary_start: .code16 .balign 4096 cli - movl $1b, %ebx + movw $0xdead, 0 + movw $0xbeef, 2 xorl %eax, %eax movl %eax, %cr3 /* Invalidate TLB*/ /* On hyper threaded cpus, invalidating the cache here is * very very bad. Don't. */ + movw $0, 0 + movl $1b, %ebx + movw $1, 0 + movw $2, 0 /* setup the data segment */ movw %cs, %ax + movw %ax, 2 + movw $3, 0 movw %ax, %ds + movw $4, 0 + /* past this point, "0" means ds:0, i.e. cs:0, or the + * segment part of the address. + */ data32 lgdt gdtaddr - _secondary_start +// data32 lgdt %cs:gdtptr + movw $5, 0 movl %cr0, %eax + movw $6, 0 andl $0x7FFAFFD1, %eax /* PG,AM,WP,NE,TS,EM,MP = 0 */ + movw $7, 0 orl $0x60000001, %eax /* CD, NW, PE = 1 */ + movw $8, 0 movl %eax, %cr0 + movw $9, 0 + hlt + /* tested to this point but not past it */ - ljmpl $0x10, $1f + /* I am pretty sure this just jumps back into + * ROM; it's an abs jump + */ + data32 ljmp $0x10, $secondary32 + movw $0xa, 0 1: .code32 secondary32: + hlt movw $0x18, %ax movw %ax, %ds movw %ax, %es |