#
# Copyright (C) 2001-2004 Jakub Jermar
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
#
# - Redistributions of source code must retain the above copyright
#   notice, this list of conditions and the following disclaimer.
# - Redistributions in binary form must reproduce the above copyright
#   notice, this list of conditions and the following disclaimer in the
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#   derived from this software without specific prior written permission.
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## very low and hardware-level functions

# Mask for interrupts 0 - 31 (bits 0 - 31) where 0 means that int has no error word
# and 1 means interrupt with error word
#define ERROR_WORD_INTERRUPT_LIST 0x00027D00

.text

.global paging_on
.global enable_l_apic_in_msr
.global interrupt_handlers

## Turn paging on
#
# Enable paging and write-back caching in CR0.
#
paging_on:
	movl %cr0,%edx
	orl $(1<<31),%edx		# paging on
	andl $~((1<<30)|(1<<29)),%edx	# clear Cache Disable and not Write Though
	movl %edx,%cr0
	jmp 0f
0:
	ret


## Enable local APIC
#
# Enable local APIC in MSR.
#
enable_l_apic_in_msr:
	push %eax

	movl $0x1b, %ecx
	rdmsr
	orl $(1<<11),%eax
	orl $(0xfee00000),%eax
	wrmsr

	pop %eax
	ret


## Declare interrupt handlers
#
# Declare interrupt handlers for n interrupt
# vectors starting at vector i.
#
# The handlers setup data segment registers
# and call exc_dispatch().
#
.macro handler i n
	push %eax

	/*
	 * Test if this is interrupt with error word or not.
	 * Be careful about width of the shift.
	 */
	.iflt \i-32
		movl $(1<<\i), %eax
	.else
		movl $0, %eax
	.endif
	andl $ERROR_WORD_INTERRUPT_LIST,%eax

	/*
	 * If this interrupt/exception  stores error word,
	 * we need to pop EAX.
	 * If this interrupt doesn't store error word, we emulate it
	 * for the sake of consistent pstate structure. In that case
	 * we merely leave the EAX on the stack.
	 */
	jz 0f

	/*
	 * This exception stores error word.
	 */
	pop %eax
	jmp 1f

0:
	/*
	 * This interrupt doesn't store error word.
	 * Just restore EAX without doing POP.
	 */
	movl (%esp), %eax

1:
	pusha
	movl %esp, %ebp
	push %ds
	push %es

	# we must fill the data segment registers
	movw $16,%ax
	movw %ax,%ds
	movw %ax,%es

	movl $(\i),%edi
	pushl %ebp
	pushl %edi
	call exc_dispatch
	addl $8,%esp

	pop %es
	pop %ds

# Clear Nested Task flag.
	pushfl
	pop %eax
	and $0xFFFFBFFF,%eax
	push %eax
	popfl
	
	popa
	add $4,%esp	# Skip error word, whether real or fake.
	iret

	.if (\n-\i)-1
	handler "(\i+1)",\n
	.endif
.endm

# keep in sync with pm.h !!!
IDT_ITEMS=64
interrupt_handlers:
h_start:
	handler 0 64
#	handler 64 128	
#	handler 128 192
#	handler 192 256
h_end:

.data
.global interrupt_handler_size

interrupt_handler_size: .long (h_end-h_start)/IDT_ITEMS