| Line 196... |
Line 196... |
|
|
/*
|
/*
|
* Reset Exception handler
|
* Reset Exception handler
|
*/
|
*/
|
.org 0x100
|
.org 0x100
|
_reset_vector:
|
reset_vector:
|
|
|
l.movhi r3,hi(MC_BASE_ADDR)
|
l.movhi r3,hi(MC_BASE_ADDR)
|
l.ori r3,r3,lo(MC_BASE_ADDR)
|
l.ori r3,r3,lo(MC_BASE_ADDR)
|
|
|
l.addi r4,r3,MC_CSC(0)
|
l.addi r4,r3,MC_CSC(0)
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| Line 275... |
Line 275... |
l.nop
|
l.nop
|
|
|
2:
|
2:
|
|
|
|
|
l.movhi r2,hi(_reset)
|
l.movhi r2,hi(reset)
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l.ori r2,r2,lo(_reset)
|
l.ori r2,r2,lo(reset)
|
l.jr r2
|
l.jr r2
|
l.nop
|
l.nop
|
|
|
/*
|
/*
|
* Switch to a new context pointed by _task_context
|
* Switch to a new context pointed by task_context
|
*/
|
*/
|
.global _dispatch
|
.global dispatch
|
.align 4
|
.align 4
|
_dispatch:
|
dispatch:
|
/* load user task GPRs and PC */
|
/* load user task GPRs and PC */
|
l.movhi r3,hi(_task_context)
|
l.movhi r3,hi(task_context)
|
l.addi r3,r0,lo(_task_context)
|
l.addi r3,r0,lo(task_context)
|
LOADREGS_N_GO
|
LOADREGS_N_GO
|
|
|
.section .except, "ax"
|
.section .except, "ax"
|
|
|
/*
|
/*
|
* Bus Error Exception handler
|
* Bus Error Exception handler
|
*/
|
*/
|
.org 0x0200
|
.org 0x0200
|
_buserr:
|
buserr:
|
l.nop
|
l.nop
|
l.sw 0(r0),r3 /* Save r3 */
|
l.sw 0(r0),r3 /* Save r3 */
|
PRINTF(r3, _buserr_str)
|
PRINTF(r3, buserr_str)
|
_hang:
|
hang:
|
l.j _hang
|
l.j hang
|
l.nop
|
l.nop
|
|
|
_buserr_str:
|
buserr_str:
|
.ascii "Bus error exception.\n\000"
|
.ascii "Bus error exception.\n\000"
|
|
|
/*
|
/*
|
* External Interrupt Exception handler
|
* External Interrupt Exception handler
|
*/
|
*/
|
.org 0x800
|
.org 0x800
|
_extint:
|
extint:
|
l.nop
|
l.nop
|
l.sw 0(r0),r3 /* Save r3 */
|
l.sw 0(r0),r3 /* Save r3 */
|
PRINTF(r3,_extint_str)
|
PRINTF(r3,extint_str)
|
l.mfspr r3,r0,SPR_EPCR_BASE /* Get EPCR */
|
l.mfspr r3,r0,SPR_EPCR_BASE /* Get EPCR */
|
l.sw 4(r0),r3 /* and save it */
|
l.sw 4(r0),r3 /* and save it */
|
|
|
/* now save user task context */
|
/* now save user task context */
|
l.movhi r3,hi(_task_context)
|
l.movhi r3,hi(task_context)
|
l.addi r3,r0,lo(_task_context)
|
l.addi r3,r0,lo(task_context)
|
SAVEREGS
|
SAVEREGS
|
|
|
/* set kernel context's PC to kernel's scheduler */
|
/* set kernel context's PC to kernel's scheduler */
|
l.movhi r3,hi(_kernel_context)
|
l.movhi r3,hi(kernel_context)
|
l.addi r3,r0,lo(_kernel_context)
|
l.addi r3,r0,lo(kernel_context)
|
SET_CONTEXTPC(r3,_int_main,r4)
|
SET_CONTEXTPC(r3,int_main,r4)
|
|
|
/* load kernel context */
|
/* load kernel context */
|
l.movhi r3,hi(_kernel_context)
|
l.movhi r3,hi(kernel_context)
|
l.addi r3,r0,lo(_kernel_context)
|
l.addi r3,r0,lo(kernel_context)
|
LOADREGS
|
LOADREGS
|
|
|
l.movhi r3,hi(_int_main)
|
l.movhi r3,hi(int_main)
|
l.addi r3,r0,lo(_int_main)
|
l.addi r3,r0,lo(int_main)
|
l.jr r3
|
l.jr r3
|
l.nop
|
l.nop
|
|
|
_extint_str:
|
extint_str:
|
.ascii "External interrupt exception.\n\000"
|
.ascii "External interrupt exception.\n\000"
|
|
|
/*
|
/*
|
* System Call Exception handler
|
* System Call Exception handler
|
*/
|
*/
|
.org 0x0c00
|
.org 0x0c00
|
_syscall:
|
syscall:
|
l.nop
|
l.nop
|
l.sw 0(r0),r3 /* Save r3 */
|
l.sw 0(r0),r3 /* Save r3 */
|
PRINTF(r3,_syscall_str)
|
PRINTF(r3,syscall_str)
|
l.mfspr r3,r0,SPR_EPCR_BASE /* Get EPCR */
|
l.mfspr r3,r0,SPR_EPCR_BASE /* Get EPCR */
|
l.addi r3,r3,4 /* increment because EPCR instruction was already executed */
|
l.addi r3,r3,4 /* increment because EPCR instruction was already executed */
|
l.sw 4(r0),r3 /* and save it */
|
l.sw 4(r0),r3 /* and save it */
|
|
|
/* now save user task context */
|
/* now save user task context */
|
l.movhi r3,hi(_task_context)
|
l.movhi r3,hi(task_context)
|
l.addi r3,r0,lo(_task_context)
|
l.addi r3,r0,lo(task_context)
|
SAVEREGS
|
SAVEREGS
|
|
|
/* set kernel context's PC to kernel's syscall entry */
|
/* set kernel context's PC to kernel's syscall entry */
|
l.movhi r3,hi(_kernel_context)
|
l.movhi r3,hi(kernel_context)
|
l.addi r3,r0,lo(_kernel_context)
|
l.addi r3,r0,lo(kernel_context)
|
SET_CONTEXTPC(r3,_kernel_syscall,r4)
|
SET_CONTEXTPC(r3,kernel_syscall,r4)
|
|
|
/* load kernel context */
|
/* load kernel context */
|
l.movhi r3,hi(_kernel_context)
|
l.movhi r3,hi(kernel_context)
|
l.addi r3,r0,lo(_kernel_context)
|
l.addi r3,r0,lo(kernel_context)
|
LOADREGS_N_GO
|
LOADREGS_N_GO
|
|
|
_syscall_str:
|
syscall_str:
|
.ascii "System call exception.\n\000"
|
.ascii "System call exception.\n\000"
|
|
|
|
|
