#define EXCEPTION_STACK_SIZE (128+128)
-#define HANDLE_EXCEPTION ; \
- l.addi r1, r1, -EXCEPTION_STACK_SIZE ; \
- l.sw 0x1c(r1), r9 ; \
- l.jal _exception_handler ; \
- l.nop ; \
- l.lwz r9, 0x1c(r1) ; \
- l.addi r1, r1, EXCEPTION_STACK_SIZE ; \
- l.rfe ; \
- l.nop
+#define HANDLE_EXCEPTION ; \
+ l.addi r1, r1, -EXCEPTION_STACK_SIZE ; \
+ l.sw 0x1c(r1), r9 ; \
+ l.jal _exception_handler ; \
+ l.nop ; \
+ l.lwz r9, 0x1c(r1) ; \
+ l.addi r1, r1, EXCEPTION_STACK_SIZE ; \
+ l.rfe ; \
+ l.nop
.section .text, "ax", @progbits
.global _start
_start:
_reset_handler:
- l.movhi r0, 0
- l.movhi r1, 0
- l.movhi r2, 0
- l.movhi r3, 0
- l.movhi r4, 0
- l.movhi r5, 0
- l.movhi r6, 0
- l.movhi r7, 0
- l.movhi r8, 0
- l.movhi r9, 0
- l.movhi r10, 0
- l.movhi r11, 0
- l.movhi r12, 0
- l.movhi r13, 0
- l.movhi r14, 0
- l.movhi r15, 0
- l.movhi r16, 0
- l.movhi r17, 0
- l.movhi r18, 0
- l.movhi r19, 0
- l.movhi r20, 0
- l.movhi r21, 0
- l.movhi r22, 0
- l.movhi r23, 0
- l.movhi r24, 0
- l.movhi r25, 0
- l.movhi r26, 0
- l.movhi r27, 0
- l.movhi r28, 0
- l.movhi r29, 0
- l.movhi r30, 0
- l.movhi r31, 0
-
- l.ori r21, r0, SPR_SR_SM
- l.mtspr r0, r21, SPR_SR
- l.movhi r21, hi(_reset_handler)
- l.ori r21, r21, lo(_reset_handler)
- l.mtspr r0, r21, SPR_EVBAR
- /* enable caches */
- l.jal _cache_init
- l.nop
- l.j _crt0
- l.nop
-
- /* bus error */
- .org 0x200
- HANDLE_EXCEPTION
-
- /* data page fault */
- .org 0x300
- HANDLE_EXCEPTION
-
- /* instruction page fault */
- .org 0x400
- HANDLE_EXCEPTION
-
- /* tick timer */
- .org 0x500
- HANDLE_EXCEPTION
-
- /* alignment */
- .org 0x600
- HANDLE_EXCEPTION
-
- /* illegal instruction */
- .org 0x700
- HANDLE_EXCEPTION
-
- /* external interrupt */
- .org 0x800
- HANDLE_EXCEPTION
-
- /* D-TLB miss */
- .org 0x900
- HANDLE_EXCEPTION
-
- /* I-TLB miss */
- .org 0xa00
- HANDLE_EXCEPTION
-
- /* range */
- .org 0xb00
- HANDLE_EXCEPTION
-
- /* system call */
- .org 0xc00
- HANDLE_EXCEPTION
-
- /* floating point */
- .org 0xd00
- HANDLE_EXCEPTION
-
- /* trap */
- .org 0xe00
- HANDLE_EXCEPTION
-
- /* reserved */
- .org 0xf00
- HANDLE_EXCEPTION
-
- .org 0x1000
+ l.movhi r0, 0
+ l.movhi r1, 0
+ l.movhi r2, 0
+ l.movhi r3, 0
+ l.movhi r4, 0
+ l.movhi r5, 0
+ l.movhi r6, 0
+ l.movhi r7, 0
+ l.movhi r8, 0
+ l.movhi r9, 0
+ l.movhi r10, 0
+ l.movhi r11, 0
+ l.movhi r12, 0
+ l.movhi r13, 0
+ l.movhi r14, 0
+ l.movhi r15, 0
+ l.movhi r16, 0
+ l.movhi r17, 0
+ l.movhi r18, 0
+ l.movhi r19, 0
+ l.movhi r20, 0
+ l.movhi r21, 0
+ l.movhi r22, 0
+ l.movhi r23, 0
+ l.movhi r24, 0
+ l.movhi r25, 0
+ l.movhi r26, 0
+ l.movhi r27, 0
+ l.movhi r28, 0
+ l.movhi r29, 0
+ l.movhi r30, 0
+ l.movhi r31, 0
+
+ l.ori r21, r0, SPR_SR_SM
+ l.mtspr r0, r21, SPR_SR
+ l.movhi r21, hi(_reset_handler)
+ l.ori r21, r21, lo(_reset_handler)
+ l.mtspr r0, r21, SPR_EVBAR
+ /* enable caches */
+ l.jal _cache_init
+ l.nop
+ l.j _crt0
+ l.nop
+
+ /* bus error */
+ .org 0x200
+ HANDLE_EXCEPTION
+
+ /* data page fault */
+ .org 0x300
+ HANDLE_EXCEPTION
+
+ /* instruction page fault */
+ .org 0x400
+ HANDLE_EXCEPTION
+
+ /* tick timer */
+ .org 0x500
+ HANDLE_EXCEPTION
+
+ /* alignment */
+ .org 0x600
+ HANDLE_EXCEPTION
+
+ /* illegal instruction */
+ .org 0x700
+ HANDLE_EXCEPTION
+
+ /* external interrupt */
+ .org 0x800
+ HANDLE_EXCEPTION
+
+ /* D-TLB miss */
+ .org 0x900
+ HANDLE_EXCEPTION
+
+ /* I-TLB miss */
+ .org 0xa00
+ HANDLE_EXCEPTION
+
+ /* range */
+ .org 0xb00
+ HANDLE_EXCEPTION
+
+ /* system call */
+ .org 0xc00
+ HANDLE_EXCEPTION
+
+ /* floating point */
+ .org 0xd00
+ HANDLE_EXCEPTION
+
+ /* trap */
+ .org 0xe00
+ HANDLE_EXCEPTION
+
+ /* reserved */
+ .org 0xf00
+ HANDLE_EXCEPTION
+
+ .org 0x1000
_crt0:
- /* Setup stack and global pointer */
- l.movhi r1, hi(_fstack)
- l.ori r1, r1, lo(_fstack)
+ /* Setup stack and global pointer */
+ l.movhi r1, hi(_fstack)
+ l.ori r1, r1, lo(_fstack)
/*
- l.movhi r16, hi(_gp)
- l.ori r16, gp, lo(_gp)
+ l.movhi r16, hi(_gp)
+ l.ori r16, gp, lo(_gp)
*/
- /* Clear BSS */
- l.movhi r21, hi(_fbss)
- l.ori r21, r21, lo(_fbss)
- l.movhi r3, hi(_ebss)
- l.ori r3, r3, lo(_ebss)
+ /* Clear BSS */
+ l.movhi r21, hi(_fbss)
+ l.ori r21, r21, lo(_fbss)
+ l.movhi r3, hi(_ebss)
+ l.ori r3, r3, lo(_ebss)
.clearBSS:
- l.sfeq r21, r3
- l.bf .callMain
- l.nop
- l.sw 0(r21), r0
- l.addi r21, r21, 4
- l.j .clearBSS
- l.nop
+ l.sfeq r21, r3
+ l.bf .callMain
+ l.nop
+ l.sw 0(r21), r0
+ l.addi r21, r21, 4
+ l.j .clearBSS
+ l.nop
.callMain:
- l.j main
- l.nop
+ l.j main
+ l.nop
_exception_handler:
- l.sw 0x00(r1), r2
- l.sw 0x04(r1), r3
- l.sw 0x08(r1), r4
- l.sw 0x0c(r1), r5
- l.sw 0x10(r1), r6
- l.sw 0x14(r1), r7
- l.sw 0x18(r1), r8
- l.sw 0x20(r1), r10
- l.sw 0x24(r1), r11
- l.sw 0x28(r1), r12
- l.sw 0x2c(r1), r13
- l.sw 0x30(r1), r14
- l.sw 0x34(r1), r15
- l.sw 0x38(r1), r16
- l.sw 0x3c(r1), r17
- l.sw 0x40(r1), r18
- l.sw 0x44(r1), r19
- l.sw 0x48(r1), r20
- l.sw 0x4c(r1), r21
- l.sw 0x50(r1), r22
- l.sw 0x54(r1), r23
- l.sw 0x58(r1), r24
- l.sw 0x5c(r1), r25
- l.sw 0x60(r1), r26
- l.sw 0x64(r1), r27
- l.sw 0x68(r1), r28
- l.sw 0x6c(r1), r29
- l.sw 0x70(r1), r30
- l.sw 0x74(r1), r31
-
- /* Save return address */
- l.or r14, r0, r9
- /* send stack pointer as argument */
- l.or r4, r0, r1
- /* Call exception handler with the link address as argument */
- l.jal exception_handler
- l.or r3, r0, r14
-
- /* Load return address */
- l.or r9, r0, r14
- /* Restore state */
- l.lwz r2, 0x00(r1)
- l.lwz r3, 0x04(r1)
- l.lwz r4, 0x08(r1)
- l.lwz r5, 0x0c(r1)
- l.lwz r6, 0x10(r1)
- l.lwz r7, 0x14(r1)
- l.lwz r8, 0x18(r1)
- l.lwz r10, 0x20(r1)
- l.lwz r11, 0x24(r1)
- l.lwz r12, 0x28(r1)
- l.lwz r13, 0x2c(r1)
- l.lwz r14, 0x30(r1)
- l.lwz r15, 0x34(r1)
- l.lwz r16, 0x38(r1)
- l.lwz r17, 0x3c(r1)
- l.lwz r18, 0x40(r1)
- l.lwz r19, 0x44(r1)
- l.lwz r20, 0x48(r1)
- l.lwz r21, 0x4c(r1)
- l.lwz r22, 0x50(r1)
- l.lwz r23, 0x54(r1)
- l.lwz r24, 0x58(r1)
- l.lwz r25, 0x5c(r1)
- l.lwz r26, 0x60(r1)
- l.lwz r27, 0x64(r1)
- l.lwz r28, 0x68(r1)
- l.lwz r29, 0x6c(r1)
- l.lwz r30, 0x70(r1)
- l.lwz r31, 0x74(r1)
- l.jr r9
- l.nop
+ l.sw 0x00(r1), r2
+ l.sw 0x04(r1), r3
+ l.sw 0x08(r1), r4
+ l.sw 0x0c(r1), r5
+ l.sw 0x10(r1), r6
+ l.sw 0x14(r1), r7
+ l.sw 0x18(r1), r8
+ l.sw 0x20(r1), r10
+ l.sw 0x24(r1), r11
+ l.sw 0x28(r1), r12
+ l.sw 0x2c(r1), r13
+ l.sw 0x30(r1), r14
+ l.sw 0x34(r1), r15
+ l.sw 0x38(r1), r16
+ l.sw 0x3c(r1), r17
+ l.sw 0x40(r1), r18
+ l.sw 0x44(r1), r19
+ l.sw 0x48(r1), r20
+ l.sw 0x4c(r1), r21
+ l.sw 0x50(r1), r22
+ l.sw 0x54(r1), r23
+ l.sw 0x58(r1), r24
+ l.sw 0x5c(r1), r25
+ l.sw 0x60(r1), r26
+ l.sw 0x64(r1), r27
+ l.sw 0x68(r1), r28
+ l.sw 0x6c(r1), r29
+ l.sw 0x70(r1), r30
+ l.sw 0x74(r1), r31
+
+ /* Save return address */
+ l.or r14, r0, r9
+ /* send stack pointer as argument */
+ l.or r4, r0, r1
+ /* Call exception handler with the link address as argument */
+ l.jal exception_handler
+ l.or r3, r0, r14
+
+ /* Load return address */
+ l.or r9, r0, r14
+ /* Restore state */
+ l.lwz r2, 0x00(r1)
+ l.lwz r3, 0x04(r1)
+ l.lwz r4, 0x08(r1)
+ l.lwz r5, 0x0c(r1)
+ l.lwz r6, 0x10(r1)
+ l.lwz r7, 0x14(r1)
+ l.lwz r8, 0x18(r1)
+ l.lwz r10, 0x20(r1)
+ l.lwz r11, 0x24(r1)
+ l.lwz r12, 0x28(r1)
+ l.lwz r13, 0x2c(r1)
+ l.lwz r14, 0x30(r1)
+ l.lwz r15, 0x34(r1)
+ l.lwz r16, 0x38(r1)
+ l.lwz r17, 0x3c(r1)
+ l.lwz r18, 0x40(r1)
+ l.lwz r19, 0x44(r1)
+ l.lwz r20, 0x48(r1)
+ l.lwz r21, 0x4c(r1)
+ l.lwz r22, 0x50(r1)
+ l.lwz r23, 0x54(r1)
+ l.lwz r24, 0x58(r1)
+ l.lwz r25, 0x5c(r1)
+ l.lwz r26, 0x60(r1)
+ l.lwz r27, 0x64(r1)
+ l.lwz r28, 0x68(r1)
+ l.lwz r29, 0x6c(r1)
+ l.lwz r30, 0x70(r1)
+ l.lwz r31, 0x74(r1)
+ l.jr r9
+ l.nop
_cache_init:
- /*
- This function is to be used ONLY during reset, before main() is called.
- TODO: Perhaps break into individual enable instruction/data cache
- sections functions, and provide disable functions, also, all
- callable from C
- */
-
- /* Instruction cache enable */
- /* Check if IC present and skip enabling otherwise */
+ /*
+ This function is to be used ONLY during reset, before main() is called.
+ TODO: Perhaps break into individual enable instruction/data cache
+ sections functions, and provide disable functions, also, all
+ callable from C
+ */
+
+ /* Instruction cache enable */
+ /* Check if IC present and skip enabling otherwise */
#if 1
.L6:
- l.mfspr r3,r0,SPR_UPR
- l.andi r7,r3,SPR_UPR_ICP
- l.sfeq r7,r0
- l.bf .L8
- l.nop
-
- /* Disable IC */
- l.mfspr r6,r0,SPR_SR
- l.addi r5,r0,-1
- l.xori r5,r5,SPR_SR_ICE
- l.and r5,r6,r5
- l.mtspr r0,r5,SPR_SR
-
- /* Establish cache block size
- If BS=0, 16;
- If BS=1, 32;
- r14 contain block size
- */
- l.mfspr r3,r0,SPR_ICCFGR
- l.andi r7,r3,SPR_ICCFGR_CBS
- l.srli r8,r7,7
- l.ori r4,r0,16
- l.sll r14,r4,r8
-
- /* Establish number of cache sets
- r10 contains number of cache sets
- r8 contains log(# of cache sets)
- */
- l.andi r7,r3,SPR_ICCFGR_NCS
- l.srli r8,r7,3
- l.ori r4,r0,1
- l.sll r10,r4,r8
-
- /* Invalidate IC */
- l.addi r6,r0,0
- l.sll r5,r14,r8
-
-.L7: l.mtspr r0,r6,SPR_ICBIR
- l.sfne r6,r5
- l.bf .L7
- l.add r6,r6,r14
-
- /* Enable IC */
- l.mfspr r6,r0,SPR_SR
- l.ori r6,r6,SPR_SR_ICE
- l.mtspr r0,r6,SPR_SR
- l.nop
- l.nop
- l.nop
- l.nop
- l.nop
- l.nop
- l.nop
- l.nop
- /* Data cache enable */
- /* Check if DC present and skip enabling otherwise */
+ l.mfspr r3,r0,SPR_UPR
+ l.andi r7,r3,SPR_UPR_ICP
+ l.sfeq r7,r0
+ l.bf .L8
+ l.nop
+
+ /* Disable IC */
+ l.mfspr r6,r0,SPR_SR
+ l.addi r5,r0,-1
+ l.xori r5,r5,SPR_SR_ICE
+ l.and r5,r6,r5
+ l.mtspr r0,r5,SPR_SR
+
+ /* Establish cache block size
+ If BS=0, 16;
+ If BS=1, 32;
+ r14 contain block size
+ */
+ l.mfspr r3,r0,SPR_ICCFGR
+ l.andi r7,r3,SPR_ICCFGR_CBS
+ l.srli r8,r7,7
+ l.ori r4,r0,16
+ l.sll r14,r4,r8
+
+ /* Establish number of cache sets
+ r10 contains number of cache sets
+ r8 contains log(# of cache sets)
+ */
+ l.andi r7,r3,SPR_ICCFGR_NCS
+ l.srli r8,r7,3
+ l.ori r4,r0,1
+ l.sll r10,r4,r8
+
+ /* Invalidate IC */
+ l.addi r6,r0,0
+ l.sll r5,r14,r8
+
+.L7: l.mtspr r0,r6,SPR_ICBIR
+ l.sfne r6,r5
+ l.bf .L7
+ l.add r6,r6,r14
+
+ /* Enable IC */
+ l.mfspr r6,r0,SPR_SR
+ l.ori r6,r6,SPR_SR_ICE
+ l.mtspr r0,r6,SPR_SR
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ l.nop
+ /* Data cache enable */
+ /* Check if DC present and skip enabling otherwise */
#endif
.L8:
#if 1
- l.mfspr r3,r0,SPR_UPR
- l.andi r7,r3,SPR_UPR_DCP
- l.sfeq r7,r0
- l.bf .L10
- l.nop
- /* Disable DC */
- l.mfspr r6,r0,SPR_SR
- l.addi r5,r0,-1
- l.xori r5,r5,SPR_SR_DCE
- l.and r5,r6,r5
- l.mtspr r0,r5,SPR_SR
- /* Establish cache block size
- If BS=0, 16;
- If BS=1, 32;
- r14 contain block size
- */
- l.mfspr r3,r0,SPR_DCCFGR
- l.andi r7,r3,SPR_DCCFGR_CBS
- l.srli r8,r7,7
- l.ori r4,r0,16
- l.sll r14,r4,r8
- /* Establish number of cache sets
- r10 contains number of cache sets
- r8 contains log(# of cache sets)
- */
- l.andi r7,r3,SPR_DCCFGR_NCS
- l.srli r8,r7,3
- l.ori r4,r0,1
- l.sll r10,r4,r8
- /* Invalidate DC */
- l.addi r6,r0,0
- l.sll r5,r14,r8
+ l.mfspr r3,r0,SPR_UPR
+ l.andi r7,r3,SPR_UPR_DCP
+ l.sfeq r7,r0
+ l.bf .L10
+ l.nop
+ /* Disable DC */
+ l.mfspr r6,r0,SPR_SR
+ l.addi r5,r0,-1
+ l.xori r5,r5,SPR_SR_DCE
+ l.and r5,r6,r5
+ l.mtspr r0,r5,SPR_SR
+ /* Establish cache block size
+ If BS=0, 16;
+ If BS=1, 32;
+ r14 contain block size
+ */
+ l.mfspr r3,r0,SPR_DCCFGR
+ l.andi r7,r3,SPR_DCCFGR_CBS
+ l.srli r8,r7,7
+ l.ori r4,r0,16
+ l.sll r14,r4,r8
+ /* Establish number of cache sets
+ r10 contains number of cache sets
+ r8 contains log(# of cache sets)
+ */
+ l.andi r7,r3,SPR_DCCFGR_NCS
+ l.srli r8,r7,3
+ l.ori r4,r0,1
+ l.sll r10,r4,r8
+ /* Invalidate DC */
+ l.addi r6,r0,0
+ l.sll r5,r14,r8
.L9:
- l.mtspr r0,r6,SPR_DCBIR
- l.sfne r6,r5
- l.bf .L9
- l.add r6,r6,r14
- /* Enable DC */
- l.mfspr r6,r0,SPR_SR
- l.ori r6,r6,SPR_SR_DCE
- l.mtspr r0,r6,SPR_SR
+ l.mtspr r0,r6,SPR_DCBIR
+ l.sfne r6,r5
+ l.bf .L9
+ l.add r6,r6,r14
+ /* Enable DC */
+ l.mfspr r6,r0,SPR_SR
+ l.ori r6,r6,SPR_SR_DCE
+ l.mtspr r0,r6,SPR_SR
#endif
.L10:
- /* Return */
- l.jr r9
- l.nop
+ /* Return */
+ l.jr r9
+ l.nop