X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Kernel%2Farch%2Fx86_64%2Fdesctab.asm;h=de606ea63f6a1bc00586aebfa2185bd80659b071;hb=9f407c493c33928e0f19b834699d9694036ca42e;hp=aec7656cbc2b789b83ff04455c403aef07fc7605;hpb=e7d03978fb7c0c6ab1250e56e73afba9ffb89923;p=tpg%2Facess2.git

diff --git a/Kernel/arch/x86_64/desctab.asm b/Kernel/arch/x86_64/desctab.asm
index aec7656c..de606ea6 100644
--- a/Kernel/arch/x86_64/desctab.asm
+++ b/Kernel/arch/x86_64/desctab.asm
@@ -3,49 +3,12 @@
 ;
 [BITS 64]
 
-MM_LOCALAPIC	equ	0xFFFFFD0000000000
-
-[section .text]
-Desctab_Init:
-	; Install IRQ Handlers
-
-[section .data]
-gIDT:
-	times 256	dw	0x00080000, 0x00008E00, 0, 0	; 64-bit Interrupt Gate, CS = 0x8, IST0
-
-%macro DEFERR	1
-Isr%1:
-	push	0
-	push	%1
-	jmp	ErrorCommon
-%endmacro
-%macro DEFERRNO	1
-Isr%1:
-	push	%1
-	jmp	ErrorCommon
-%endmacro
-
-%macro DEFIRQ	1
-Irq%1:
-	push	0
-	push	%1
-	jmp	IrqCommon
-%endmacro
+%define NUM_IRQ_CALLBACKS	4
 
-%macro PUSH_EX	1-*
-	%rep %0
-	push %1
-	%rotate 1
-	%endrep
-%endmacro
-%macro POP_EX	1-*
-	%rep %0
-	%rotate -1
-	pop %1
-	%endrep
-%endmacro
+MM_LOCALAPIC	equ	0xFFFFFD0000000000
 
 %macro PUSH_GPR	0
+	mov [rsp-0x60], rsp
 	mov [rsp-0x08], r15
 	mov [rsp-0x10], r14
 	mov [rsp-0x18], r13
@@ -57,7 +20,6 @@ Irq%1:
 	mov [rsp-0x48], rdi
 	mov [rsp-0x50], rsi
 	mov [rsp-0x58], rbp
-	mov [rsp-0x60], rsp
 	mov [rsp-0x68], rbx
 	mov [rsp-0x70], rdx
 	mov [rsp-0x78], rcx
@@ -72,8 +34,8 @@ Irq%1:
 	mov r12, [rsp-0x20]
 	mov r11, [rsp-0x28]
 	mov r10, [rsp-0x30]
-	mov r9, [rsp-0x38]
-	mov r8, [rsp-0x40]
+	mov r9,  [rsp-0x38]
+	mov r8,  [rsp-0x40]
 	mov rdi, [rsp-0x48]
 	mov rsi, [rsp-0x50]
 	mov rbp, [rsp-0x58]
@@ -84,6 +46,107 @@ Irq%1:
 	mov rax, [rsp-0x80]
 %endmacro
 
+[section .text]
+Desctab_Init:
+	; Install IRQ Handlers
+	ret
+
+; int IRQ_AddHandler(int IRQ, void (*Handler)(int IRQ))
+; Return Values:
+;  0 on Success
+; -1 on an invalid IRQ Number
+; -2 when no slots are avaliable
+[global IRQ_AddHandler]
+IRQ_AddHandler:
+	; RDI - IRQ Number
+	; RSI - Callback
+	
+	cmp rdi, 16
+	jb .numOK
+	xor rax, rax
+	dec rax
+	jmp .ret
+.numOK:
+
+	mov rax, rdi
+	shr rax, 3+2
+	mov rcx, gaIRQ_Handlers
+	add rax, rcx
+	
+	; Find a free callback slot
+	%rep NUM_IRQ_CALLBACKS
+	mov rdx, [rax]
+	test rdx, rdx
+	jz .assign
+	add rax, 8
+	%endrep
+	; None found, return -2
+	xor rax, rax
+	dec rax
+	dec rax
+	jmp .ret
+	
+	; Assign the IRQ Callback
+.assign:
+	mov [rax], rsi
+	xor rax, rax
+
+.ret:
+	ret
+
+%macro DEFERR	1
+Isr%1:
+	push	0
+	push	%1
+	jmp	ErrorCommon
+%endmacro
+%macro DEFERRNO	1
+Isr%1:
+	push	%1
+	jmp	ErrorCommon
+%endmacro
+
+%macro DEFIRQ	1
+Irq%1:
+	push	0
+	push	%1
+	jmp	IrqCommon
+%endmacro
+
+IrqCommon:
+	PUSH_GPR
+	
+	mov rbx, [rsp+16*8]	; Calculate address
+	shr rbx, 3+2	; *8*4
+	mov rax, gaIRQ_Handlers
+	add rbx, rax
+	
+	%assign i 0
+	%rep NUM_IRQ_CALLBACKS
+	mov rax, [rbx]
+	test rax, rax
+	mov rdi, [rsp+16*8]	; Get IRQ number
+	jz .skip.%[i]
+	call rax	; 2 Bytes (Op and Mod/RM)
+.skip.%[i]:
+	add rbx, 8
+	%assign i i+1
+	%endrep
+	
+	mov rdi, [rsp+16*8]	; Get IRQ number
+	cmp rdi, 8
+	mov al, 0x20
+	jb .skipAckSecondary
+	mov dx, 0x00A0
+	out dx, al
+.skipAckSecondary:
+	mov dx, 0x0020
+	out dx, al
+	
+	POP_GPR
+	add rsp, 16
+	iret
+
 [extern Proc_Scheduler]
 SchedulerIRQ:
 	; TODO: Find Current CPU
@@ -100,3 +163,10 @@ SchedulerIRQ:
 	;POP_FPU
 	POP_GPR
 	iret
+
+[section .data]
+gIDT:
+	times 256	dw	0x00080000, 0x00008E00, 0, 0	; 64-bit Interrupt Gate, CS = 0x8, IST0
+
+gaIRQ_Handlers:
+	times	16*NUM_IRQ_CALLBACKS	dq	0