kolibrios/kernel/branches/Kolibri-acpi/detect/getcache.inc

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;;                                                              ;;
;; Copyright (C) KolibriOS team 2004-2011. All rights reserved. ;;
;; Distributed under terms of the GNU General Public License    ;;
;;                                                              ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

$Revision$

        pusha

        mov     eax, [pg_data.pages_free]
;   1/32
        shr     eax, 5
;   round off up to 8 pages
        shr     eax, 3
        shl     eax, 3
;   translate pages in butes *4096
        shl     eax, 12
;       check a upper size of the cache, no more than 1 Mb on the physical device
        cmp     eax, 1024*1024
        jbe     @f
        mov     eax, 1024*1024
        jmp     .continue
@@:
;       check a lower size of the cache, not less than 128 Kb on the physical device
        cmp     eax, 128*1024
        jae     @f
        mov     eax, 128*1024
@@:
.continue:
        mov     [cache_ide0_size], eax
        mov     [cache_ide1_size], eax
        mov     [cache_ide2_size], eax
        mov     [cache_ide3_size], eax
        xor     eax, eax
        mov     [hdd_appl_data], 1;al
        mov     [cd_appl_data], 1

        test    byte [DRIVE_DATA+1], 2
        je      .ide2 
        mov     esi, cache_ide3
        call    get_cache_ide
.ide2:
        test    byte [DRIVE_DATA+1], 8
        je      .ide1
        mov     esi, cache_ide2
        call    get_cache_ide
.ide1:
        test    byte [DRIVE_DATA+1], 0x20
        je      .ide0
        mov     esi, cache_ide1
        call    get_cache_ide
.ide0:
        test    byte [DRIVE_DATA+1], 0x80
        je      @f
        mov     esi, cache_ide0
        call    get_cache_ide
@@:
        jmp     end_get_cache

get_cache_ide:
        and     [esi+cache_ide0_search_start-cache_ide0], 0
        and     [esi+cache_ide0_appl_search_start-cache_ide0], 0
        push    ecx
        stdcall kernel_alloc, [esi+cache_ide0_size-cache_ide0]
        mov     [esi+cache_ide0_pointer-cache_ide0], eax
        pop     ecx
        mov     edx, eax
        mov     eax, [esi+cache_ide0_size-cache_ide0]
        shr     eax, 3
        mov     [esi+cache_ide0_system_data_size-cache_ide0], eax
        mov     ebx, eax
        imul    eax, 7
        mov     [esi+cache_ide0_appl_data_size-cache_ide0], eax
        add     ebx, edx
        mov     [esi+cache_ide0_data_pointer-cache_ide0], ebx

.cd:
        push    ecx
        mov     eax, [esi+cache_ide0_system_data_size-cache_ide0]
        call    calculate_for_cd
        add     eax, [esi+cache_ide0_pointer-cache_ide0]
        mov     [esi+cache_ide0_system_data-cache_ide0], eax
        mov     [esi+cache_ide0_system_sad_size-cache_ide0], ecx

        push    edi
        mov     edi, [esi+cache_ide0_pointer-cache_ide0]
        call    clear_ide_cache
        pop     edi

        mov     eax, [esi+cache_ide0_appl_data_size-cache_ide0]
        call    calculate_for_cd
        add     eax, [esi+cache_ide0_data_pointer-cache_ide0]
        mov     [esi+cache_ide0_appl_data-cache_ide0], eax
        mov     [esi+cache_ide0_appl_sad_size-cache_ide0], ecx

        push    edi
        mov     edi, [esi+cache_ide0_data_pointer-cache_ide0]
        call    clear_ide_cache
        pop     edi

        pop     ecx
        ret

calculate_for_cd:
        push    eax
        mov     ebx, eax
        shr     eax, 11
        shl     eax, 3
        sub     ebx, eax
        shr     ebx, 11
        mov     ecx, ebx
        shl     ebx, 11
        pop     eax
        sub     eax, ebx
        dec     ecx
        ret

clear_ide_cache:
        push    eax
        shl     ecx, 1
        xor     eax, eax
        cld
        rep stosd
        pop     eax
        ret

end_get_cache:
        popa