diff options
Diffstat (limited to 'cpu/mpc824x/drivers/epic/epic2.S')
| -rw-r--r-- | cpu/mpc824x/drivers/epic/epic2.S | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/cpu/mpc824x/drivers/epic/epic2.S b/cpu/mpc824x/drivers/epic/epic2.S new file mode 100644 index 0000000..8979f88 --- /dev/null +++ b/cpu/mpc824x/drivers/epic/epic2.S @@ -0,0 +1,196 @@ +/************************************** + * + * copyright @ Motorola, 1999 + * + **************************************/ + +#include <ppc_asm.tmpl> +#include <ppc_defs.h> +#include <asm/processor.h> + +/********************************************* + * function: CoreExtIntEnable + * + * description: Enable 603e core external interrupt + * + * note: mtmsr is context-synchronization + **********************************************/ + .text + .align 2 + .global CoreExtIntEnable +CoreExtIntEnable: + mfmsr r3 + + ori r3,r3,0x8000 /* enable external interrupt */ + mtmsr r3 + + bclr 20, 0 + +/******************************************* + * function: CoreExtIntDisable + * + * description: Disable 603e core external interrupt + * + * note: + *******************************************/ + .text + .align 2 + .global CoreExtIntDisable +CoreExtIntDisable: + mfmsr r4 + + xor r3,r3,r3 + or r3,r3,r4 + + andis. r4,r4,0xffff + andi. r3,r3,0x7fff /* disable external interrupt */ + + or r3,r3,r4 + mtmsr r3 + + bclr 20, 0 + +/********************************************************* + * function: epicEOI + * + * description: signal the EOI and restore machine status + * Input: r3 - value of eumbbar + * Output: r3 - value of eumbbar + * r4 - ISR vector value + * note: + ********************************************************/ + .text + .align 2 + .global epicEOI +epicEOI: + lis r5,0x0006 /* Build End Of Interrupt Register offset */ + ori r5,r5,0x00b0 + xor r7,r7,r7 /* Clear r7 */ + stwbrx r7,r5,r3 /* Save r7, writing to this register will + * intidate the end of processing the + * highest interrupt. + */ + sync + + /* ---RESTORE MACHINE STATE */ + mfmsr r13 /* Clear Recoverable Interrupt bit in MSR */ + or r7,r7,r13 + + andis. r7,r7,0xffff + andi. r13,r13,0x7ffd /* (and disable interrupts) */ + or r13,r13,r7 + mtmsr r13 + + lwz r13,0x1c(r1) /* pull ctr */ + mtctr r13 + + lwz r13,0x18(r1) /* pull xer */ + mtctr r13 + + lwz r13,0x14(r1) /* pull lr */ + mtctr r13 + + lwz r13,0x10(r1) /* Pull SRR1 from stack */ + mtspr SRR1,r13 /* Restore SRR1 */ + + lwz r13,0xc(r1) /* Pull SRR0 from stack */ + mtspr SRR0,r13 /* Restore SRR0 */ + + lwz r13,0x8(r1) /* Pull User stack pointer from stack */ + mtspr SPRG1,r13 /* Restore SPRG1 */ + + lwz r4,0x4(r1) /* vector value */ + lwz r3,0x0(r1) /* eumbbar */ + sync + + addi r1,r1,0x20 /* Deallocate stack */ + mtspr SPRG0,r1 /* Save updated Supervisor stack pointer */ + mfspr r1,SPRG1 /* Restore User stack pointer */ + + bclr 20,0 + +/*********************************************************** + * function: exception routine called by exception vector + * at 0x500, external interrupt + * + * description: Kahlua EPIC controller + * + * input: r3 - content of eumbbar + * output: r3 - ISR return value + * r4 - Interrupt vector number + * note: + ***********************************************************/ + + .text + .align 2 + .global epic_exception + +epic_exception: + + /*---SAVE MACHINE STATE TO A STACK */ + mtspr SPRG1,r1 /* Save User stack pointer to SPRG1 */ + mfspr r1,SPRG0 /* Load Supervisor stack pointer into r1 */ + + stwu r3,-0x20(r1) /* Push the value of eumbbar onto stack */ + + mfspr r3,SPRG1 /* Push User stack pointer onto stack */ + stw r3,0x8(r1) + mfspr r3,SRR0 /* Push SRR0 onto stack */ + stw r1,0xc(r1) + mfspr r3,SRR1 /* Push SRR1 onto stack */ + stw r3,0x10(r1) + mflr r3 + stw r3,0x14(r1) /* Push LR */ + mfxer r3 + stw r3,0x18(r1) /* Push Xer */ + mfctr r3 + stw r3,0x1c(r1) /* Push CTR */ + + mtspr SPRG0,r1 /* Save updated Supervisor stack pointer + * value to SPRG0 + */ + mfmsr r3 + ori r3,r3,0x0002 /* Set Recoverable Interrupt bit in MSR */ + mtmsr r3 + + /* ---READ IN THE EUMBAR REGISTER */ + lwz r6,0(r1) /* this is eumbbar */ + sync + + /* ---READ EPIC REGISTER: PROCESSOR INTERRUPT ACKNOWLEDGE REGISTER */ + lis r5,0x0006 /* Build Interrupt Acknowledge Register + * offset + */ + ori r5,r5,0x00a0 + lwbrx r7,r5,r6 /* Load interrupt vector into r7 */ + sync + + /* --MASK OFF ALL BITS EXCEPT THE VECTOR */ + xor r3,r3,r3 + xor r4,r4,r4 + or r3, r3, r6 /* eumbbar in r3 */ + andi. r4,r7,0x00ff /* Mask off bits, vector in r4 */ + + stw r4,0x04(r1) /* save the vector value */ + + lis r5,epicISR@ha + ori r5,r5,epicISR@l + mtlr r5 + blrl + + xor r30,r30,r30 + or r30,r30,r3 /* save the r3 which containts the return value from epicISR */ + + /* ---READ IN THE EUMBAR REGISTER */ + lwz r3,0(r1) + sync + + lis r5,epicEOI@ha + ori r5,r5,epicEOI@l + mtlr r5 + blrl + + xor r3,r3,r3 + or r3,r3,r30 /* restore the ISR return value */ + + bclr 20,0 |