-
-/*
- * r0 - SYSCALL number
- * r3-... arguments
- */
-SystemCall:
- addis r11,r0,0 /* get functions table addr */
- ori r11,r11,0 /* Note: this code is patched in trap_init */
- addis r12,r0,0 /* get number of functions */
- ori r12,r12,0
-
- cmplw 0,r0,r12
- bge 1f
-
- rlwinm r0,r0,2,0,31 /* fn_addr = fn_tbl[r0] */
- add r11,r11,r0
- lwz r11,0(r11)
-
- li r20,0xd00-4 /* Get stack pointer */
- lwz r12,0(r20)
- subi r12,r12,12 /* Adjust stack pointer */
- li r0,0xc00+_end_back-SystemCall
- cmplw 0,r0,r12 /* Check stack overflow */
- bgt 1f
- stw r12,0(r20)
-
- mflr r0
- stw r0,0(r12)
- mfspr r0,SRR0
- stw r0,4(r12)
- mfspr r0,SRR1
- stw r0,8(r12)
-
- li r12,0xc00+_back-SystemCall
- mtlr r12
- mtspr SRR0,r11
-
-1: SYNC
- rfi
-_back:
-
- mfmsr r11 /* Disable interrupts */
- li r12,0
- ori r12,r12,MSR_EE
- andc r11,r11,r12
- SYNC /* Some chip revs need this... */
- mtmsr r11
- SYNC
-
- li r12,0xd00-4 /* restore regs */
- lwz r12,0(r12)
-
- lwz r11,0(r12)
- mtlr r11
- lwz r11,4(r12)
- mtspr SRR0,r11
- lwz r11,8(r12)
- mtspr SRR1,r11
-
- addi r12,r12,12 /* Adjust stack pointer */
- li r20,0xd00-4
- stw r12,0(r20)
-
- SYNC
- rfi
-_end_back:
-