Commenting and cleanup

[tpg/acess2.git] / Kernel / arch / armv7 / start.S

diff --git a/Kernel/arch/armv7/start.S b/Kernel/arch/armv7/start.S
index 089ead5..5a8e4eb 100644 (file)
--- a/Kernel/arch/armv7/start.S
+++ b/Kernel/arch/armv7/start.S
@@ -9,7 +9,7 @@
 interrupt_vector_table:
 ivt_reset:     b _start @ Reset
 ivt_undef:     b .     @ #UD
-ivt_svc:       b SyscallHandler @ SVC (SWI assume)
+ivt_svc:       b SVC_Handler @ SVC (used to be called SWI)
 ivt_prefetch:  b PrefetchAbort @ Prefetch abort
 ivt_data:      b DataAbort     @ Data abort
 ivt_unused:    b .     @ Not Used
@@ -65,8 +65,72 @@ _ptr_kmain:
 .comm irqstack, 0x1000 @ ; 4KiB Stack
 .comm abortstack, 0x1000       @ ; 4KiB Stack
 
-SyscallHandler:
-       b .
+.extern SyscallHandler
+SVC_Handler:
+@      sub lr, #4
+       srsdb sp!, #19  @ Save state to stack
+       cpsie ifa, #19  @ Ensure we're in supervisor with interrupts enabled (should already be there)
+       push {r0-r12}
+
+       ldr r4, [lr,#-4]
+       mvn r5, #0xFF000000
+       and r4, r5
+
+       tst r4, #0x1000 
+       bne .arm_specifics
+
+       push {r4}
+
+       mov r0, sp
+       ldr r4, =SyscallHandler
+       blx r4
+       
+       pop {r2}        @ errno
+       pop {r0,r1}     @ Ret/RetHi
+       add sp, #2*4    @ Saved r2/r3
+       
+       pop {r4-r12}
+       rfeia sp!       @ Pop state (actually RFEFD)
+.arm_specifics:
+       and r4, #0xFF
+
+@
+@ Cache invalidation
+       cmp r4, #0x001
+       bne 1f
+       @ Page align
+       mov r2, #0x1000
+       sub r2, #1
+       add r1, r2
+       mvn r2, r2
+       and r0, r2
+       and r1, r2
+       cmp r0, #0x78000000
+       cmpls r1, #0x78000000
+       movge r0, #-1
+       movge r1, #0
+       movge r2, #1
+       bge .ret
+
+2:
+       cmp r0, r1
+       mcrlt p15, 0, r0, c7, c5, 1
+       mcrlt p15, 0, r0, c7, c6, 1
+       addlt r0, #0x1000
+       blt 2b
+       mov r0, #0
+       mov r1, #0
+       mov r2, #0
+       b .ret
+1:     
+       mov r0, #-1
+       mov r1, #0
+       mov r2, #-1
+.ret:
+       add sp, #4*4
+       pop {r4-r12}
+       rfeia sp!
+
 
 .globl gpIRQHandler
 gpIRQHandler:  .long   0
@@ -114,7 +178,6 @@ DataAbort:
 
 @      POP_GPRS
 @      rfeia sp!       @ Pop state (actually RFEFD)
-       bx lr
 
 .globl PrefetchAbort
 PrefetchAbort: