# TODO: Update these constants once they're finalized in the doc.
-#define DCSR 0x790
-#define DCSR_CAUSE_DEBINT 3
-#define DCSR_HALT_OFFSET 3
-#define DCSR_DEBUGINT_OFFSET 10
-
-#define DSCRATCH 0x792
-
#define DEBUG_RAM 0x400
#define DEBUG_RAM_SIZE 64
-#define SETHALTNOT 0x100
-#define CLEARDEBINT 0x108
+#define CLEARDEBINT 0x100
+#define SETHALTNOT 0x10c
.global entry
.global resume
_resume:
li s0, 0
_resume2:
- # Clear debug interrupt.
- csrr s1, CSR_MHARTID
- sw s1, CLEARDEBINT(zero)
fence
# Restore s1.
bltz s1, restore_not_32
restore_32:
lw s1, (DEBUG_RAM + DEBUG_RAM_SIZE - 4)(zero)
- j check_halt
+ j finish_restore
restore_not_32:
slli s1, s1, 1
bltz s1, restore_128
restore_64:
ld s1, (DEBUG_RAM + DEBUG_RAM_SIZE - 8)(zero)
- j check_halt
+ j finish_restore
restore_128:
nop #lq s1, (DEBUG_RAM + DEBUG_RAM_SIZE - 16)(zero)
+finish_restore:
# s0 contains ~0 if we got here through an exception, and 0 otherwise.
# Store this to the last word in Debug RAM so the debugger can tell if
# an exception occurred.
sw s0, (DEBUG_RAM + DEBUG_RAM_SIZE - 4)(zero)
+ # Clear debug interrupt.
+ csrr s0, CSR_MHARTID
+ sw s0, CLEARDEBINT(zero)
+
check_halt:
- csrr s0, DCSR
- andi s0, s0, (1<<DCSR_HALT_OFFSET)
+ csrr s0, CSR_DCSR
+ andi s0, s0, DCSR_HALT
beqz s0, exit
j wait_for_interrupt
exit:
# Restore s0.
- csrr s0, DSCRATCH
+ csrr s0, CSR_DSCRATCH
dret
-
_entry:
# Save s0 in DSCRATCH
- csrw DSCRATCH, s0
+ csrw CSR_DSCRATCH, s0
# Check why we're here
- csrr s0, DCSR
- # cause is in bits 2:0 of dcsr
- andi s0, s0, 7
- addi s0, s0, -DCSR_CAUSE_DEBINT
+ csrr s0, CSR_DCSR
+ # cause is in bits 8:6 of dcsr
+ andi s0, s0, DCSR_CAUSE
+ addi s0, s0, -(DCSR_CAUSE_DEBUGINT<<6)
bnez s0, spontaneous_halt
jdebugram:
spontaneous_halt:
csrr s0, CSR_MHARTID
sw s0, SETHALTNOT(zero)
- csrsi DCSR, (1<<DCSR_HALT_OFFSET)
+ csrsi CSR_DCSR, DCSR_HALT
wait_for_interrupt:
- csrr s0, DCSR
- andi s0, s0, (1<<DCSR_DEBUGINT_OFFSET)
+ csrr s0, CSR_DCSR
+ andi s0, s0, DCSR_DEBUGINT
beqz s0, wait_for_interrupt
j jdebugram