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Diffstat (limited to 'contrib/syslinux/latest/core/highmem.inc')
| -rw-r--r-- | contrib/syslinux/latest/core/highmem.inc | 158 |
1 files changed, 0 insertions, 158 deletions
diff --git a/contrib/syslinux/latest/core/highmem.inc b/contrib/syslinux/latest/core/highmem.inc deleted file mode 100644 index ea386ff..0000000 --- a/contrib/syslinux/latest/core/highmem.inc +++ /dev/null @@ -1,158 +0,0 @@ -;; ----------------------------------------------------------------------- -;; -;; Copyright 1994-2008 H. Peter Anvin - All Rights Reserved -;; -;; This program is free software; you can redistribute it and/or modify -;; it under the terms of the GNU General Public License as published by -;; the Free Software Foundation, Inc., 53 Temple Place Ste 330, -;; Boston MA 02111-1307, USA; either version 2 of the License, or -;; (at your option) any later version; incorporated herein by reference. -;; -;; ----------------------------------------------------------------------- - -;; -;; highmem.inc -;; -;; Probe for the size of high memory. This can be overridden by a -;; mem= command on the command line while booting a new kernel. -;; - - section .text16 - -; -; This is set up as a subroutine; it will set up the global variable -; HighMemSize. All registers are preserved. -; -highmemsize: - push es - pushfd - pushad - - push cs - pop es - -; -; First, try INT 15:E820 (get BIOS memory map) -; -; Note: we may have to scan this multiple times, because some (daft) BIOSes -; report main memory as multiple contiguous ranges... -; -get_e820: - mov dword [E820Max],-(1 << 20) ; Max amount of high memory - mov dword [E820Mem],(1 << 20) ; End of detected high memory -.start_over: - mov di,E820Buf - xor ax,ax - mov cx,10 - rep stosw ; Clear buffer - xor ebx,ebx ; Start with first record - jmp short .do_e820 ; Skip "at end" check first time! -.int_loop: and ebx,ebx ; If we're back at beginning... - jz .e820_done ; ... we're done -.do_e820: mov eax,0000E820h - mov edx,534D4150h ; "SMAP" backwards - xor ecx,ecx - mov cl,20 ; ECX <- 20 (size of buffer) - mov di,E820Buf - int 15h - jnc .no_carry - ; If carry, ebx == 0 means error, ebx != 0 means we're done - and ebx,ebx - jnz .e820_done - jmp no_e820 -.no_carry: - cmp eax,534D4150h - jne no_e820 - cmp cx,20 - jb no_e820 - -; -; Look for a memory block starting at <= 1 MB and continuing upward -; - cmp dword [E820Buf+4], byte 0 - ja .int_loop ; Start >= 4 GB? - mov eax, [E820Buf] - cmp dword [E820Buf+16],1 - je .is_ram ; Is it memory? - ; - ; Non-memory range. Remember this as a limit; some BIOSes get the length - ; of primary RAM incorrect! - ; -.not_ram: - cmp eax, (1 << 20) - jb .int_loop ; Starts in lowmem region - cmp eax,[E820Max] - jae .int_loop ; Already above limit - mov [E820Max],eax ; Set limit - jmp .int_loop - -.is_ram: - cmp eax,[E820Mem] - ja .int_loop ; Not contiguous with our starting point - add eax,[E820Buf+8] - jc .overflow - cmp dword [E820Buf+12],0 - je .nooverflow -.overflow: - or eax,-1 -.nooverflow: - cmp eax,[E820Mem] - jbe .int_loop ; All is below our baseline - mov [E820Mem],eax - jmp .start_over ; Start over in case we find an adjacent range - -.e820_done: - mov eax,[E820Mem] - cmp eax,[E820Max] - jna .not_limited - mov eax,[E820Max] -.not_limited: - cmp eax,(1 << 20) - ja got_highmem ; Did we actually find memory? - ; otherwise fall through - -; -; INT 15:E820 failed. Try INT 15:E801. -; -no_e820: - mov ax,0e801h ; Query high memory (semi-recent) - int 15h - jc no_e801 - cmp ax,3c00h - ja no_e801 ; > 3C00h something's wrong with this call - jb e801_hole ; If memory hole we can only use low part - - mov ax,bx - shl eax,16 ; 64K chunks - add eax,(16 << 20) ; Add first 16M - jmp short got_highmem - -; -; INT 15:E801 failed. Try INT 15:88. -; -no_e801: - mov ah,88h ; Query high memory (oldest) - int 15h - cmp ax,14*1024 ; Don't trust memory >15M - jna e801_hole - mov ax,14*1024 -e801_hole: - and eax,0ffffh - shl eax,10 ; Convert from kilobytes - add eax,(1 << 20) ; First megabyte -got_highmem: -%if HIGHMEM_SLOP != 0 - sub eax,HIGHMEM_SLOP -%endif - mov [HighMemSize],eax - popad - popfd - pop es - ret ; Done! - - section .bss16 - alignb 4 -E820Buf resd 5 ; INT 15:E820 data buffer -E820Mem resd 1 ; Memory detected by E820 -E820Max resd 1 ; Is E820 memory capped? -; HighMemSize is defined in com32.inc |