65 lines
1.1 KiB
ArmAsm
65 lines
1.1 KiB
ArmAsm
.section .text
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.align 4
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/* Disable paging mask */
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.set dp, 0x7FFFFFFF
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/* Enable paging mask */
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.set ep, 0x80000000
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.global copy_page_physical
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.type copy_page_physical, @function
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copy_page_physical:
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/* Preserve contents of EBX */
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push %ebx
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/* Preserve contents of EFLAGS */
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pushf
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cli
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/* Load source and destination addresses */
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mov 12(%esp), %ebx
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mov 16(%esp), %ecx
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/* Get control register and disable paging*/
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mov %cr0, %edx
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and $dp, %edx
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mov %edx, %cr0
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/* Copy 4096 bytes */
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mov $0x400, %edx
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.page_loop:
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/* Get word at source address */
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mov (%ebx), %eax
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/* Store it at destination address */
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mov %eax, (%ecx)
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/* Increment source and destination addresses to next word */
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add $4, %ebx
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add $4, %ecx
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/* One less word to copy */
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dec %edx
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jnz .page_loop
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/* Get control register again and enable paging */
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mov %cr0, %edx
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or $ep, %edx
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mov %edx, %cr0
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/* Restore EFLAGS */
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popf
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/* Restore EBX */
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pop %ebx
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ret
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/* Read EIP */
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.global read_eip
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.type read_eip, @function
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read_eip:
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mov (%esp), %eax
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ret
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