X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=Kernel%2Farch%2Fx86%2Fdesctab.asm;h=dc064f579f7287910e44e1d6f66f00b7021892e7;hb=b1873b4cff47aae8ada8cc303ea01b475cc7ccc8;hp=615d6a278a1f28e1fbeb8bb88d15dade4b6af79b;hpb=f5ee3595addf2954bbbd5dcb9d7de72b069750e7;p=tpg%2Facess2.git

diff --git a/Kernel/arch/x86/desctab.asm b/Kernel/arch/x86/desctab.asm
index 615d6a27..dc064f57 100644
--- a/Kernel/arch/x86/desctab.asm
+++ b/Kernel/arch/x86/desctab.asm
@@ -31,7 +31,8 @@ gGDTPtr:
 ALIGN 8
 [global gIDT]
 gIDT:
-	times	256	dd	0x00080000,0x00000F00
+	; CS = 0x08, Type = 32-bit Interrupt (0xE = 1 110)
+	times	256	dd	0x00080000,0x00000E00
 [global gIDTPtr]
 gIDTPtr:
 	dw	256 * 16 - 1	; Limit
@@ -52,7 +53,9 @@ Desctab_Install:
 	jmp 0x08:.pl0code
 .pl0code:
 
-	; Set IDT
+	; Set up IDT
+	; Helper Macros
+	; - Set an IDT entry to an ISR
 %macro SETISR	1
 	mov eax, Isr%1
 	mov	WORD [gIDT + %1*8], ax
@@ -63,25 +66,34 @@ Desctab_Install:
 	or ax, 0x8000
 	mov	WORD [gIDT + %1*8 + 4], ax
 %endmacro
-%macro SETUSER	1
-	mov	ax, WORD [gIDT + %1*8 + 4]
-	or ax, 0x6000
-	mov	WORD [gIDT + %1*8 + 4], ax
+	; Enable user calling of an ISR
+%macro SET_USER	1
+	or WORD [gIDT + %1*8 + 4], 0x6000
 %endmacro
+	; Set an ISR as a trap (leaves interrupts enabled when invoked)
+%macro SET_TRAP	1
+	or WORD [gIDT + %1*8 + 4], 0x0100
+%endmacro
+
+	; Error handlers
 	%assign	i	0
 	%rep 32
 	SETISR	i
 	%assign i i+1
 	%endrep
 	
+	; User Syscall
 	SETISR	0xAC
-	SETUSER	0xAC
+	SET_USER	0xAC
+	SET_TRAP	0xAC	; Interruptable
 	
+	; MP ISRs
 	%if USE_MP
 	SETISR	0xEE	; 0xEE Timer
 	SETISR	0xEF	; 0xEF Spurious Interrupt
 	%endif
-	
+
+	; IRQs
 	%assign	i	0xF0
 	%rep 16
 	SETISR	i
@@ -198,7 +210,7 @@ DEF_SYSCALL	0xAC	; Acess System Call
 [extern SchedulerBase]
 ; AP's Timer Interrupt
 Isr0xEE:
-	push 0
+	push 0	; Line up with interrupt number
 	xchg bx, bx	; MAGIC BREAK
 	jmp SchedulerBase
 ; Spurious Interrupt
@@ -215,7 +227,8 @@ Isr0xEF:
 [extern SchedulerBase]
 [extern SetAPICTimerCount]
 Isr240:
-	push 0
+	push 0	; Line up with Argument in errors
+	push 0	; CPU Number
 	;xchg bx, bx	; MAGIC BREAK
 Isr240.jmp:
 	%if USE_MP
@@ -275,6 +288,18 @@ SyscallCommon:
 	call SyscallHandler
 	add esp, 4
 	
+	; Pass changes to TF on to the user
+	; EFLAGS is stored at ESP[4+8+2+2]
+	; 4 Segment Registers
+	; 8 GPRs
+	; 2 Error Code / Interrupt ID
+	; 2 CS/EIP
+	pushf
+	pop eax
+	and eax, 0x100	; 0x100 = Trace Flag
+	and WORD [esp+(4+8+2+2)*4], ~0x100	; Clear
+	or DWORD [esp+(4+8+2+2)*4], eax	; Set for user
+	
 	pop gs
 	pop fs
 	pop es
@@ -288,6 +313,8 @@ SyscallCommon:
 ; ------------
 [extern IRQ_Handler]
 [global IRQCommon]
+[global IRQCommon_handled]
+IRQCommon_handled equ IRQCommon.handled
 IRQCommon:
 	pusha
 	push ds
@@ -303,6 +330,7 @@ IRQCommon:
 	
 	push esp
 	call IRQ_Handler
+.handled:
 	add esp, 4
 	
 	pop gs