| /* SPDX-License-Identifier: GPL-2.0 */ |
| /* |
| * Copyright (C) 2004 Axis Communications AB |
| * |
| * Code for handling break 8, hardware breakpoint, single step, and serial |
| * port exceptions for kernel debugging purposes. |
| */ |
| |
| #include <hwregs/intr_vect.h> |
| |
| ;; Exported functions. |
| .globl kgdb_handle_exception |
| |
| kgdb_handle_exception: |
| |
| ;; Create a register image of the caller. |
| ;; |
| ;; First of all, save the ACR on the stack since we need it for address calculations. |
| ;; We put it into the register struct later. |
| |
| subq 4, $sp |
| move.d $acr, [$sp] |
| |
| ;; Now we are free to use ACR all we want. |
| ;; If we were running this handler with interrupts on, we would have to be careful |
| ;; to save and restore CCS manually, but since we aren't we treat it like every other |
| ;; register. |
| |
| move.d reg, $acr |
| move.d $r0, [$acr] ; Save R0 (start of register struct) |
| addq 4, $acr |
| move.d $r1, [$acr] ; Save R1 |
| addq 4, $acr |
| move.d $r2, [$acr] ; Save R2 |
| addq 4, $acr |
| move.d $r3, [$acr] ; Save R3 |
| addq 4, $acr |
| move.d $r4, [$acr] ; Save R4 |
| addq 4, $acr |
| move.d $r5, [$acr] ; Save R5 |
| addq 4, $acr |
| move.d $r6, [$acr] ; Save R6 |
| addq 4, $acr |
| move.d $r7, [$acr] ; Save R7 |
| addq 4, $acr |
| move.d $r8, [$acr] ; Save R8 |
| addq 4, $acr |
| move.d $r9, [$acr] ; Save R9 |
| addq 4, $acr |
| move.d $r10, [$acr] ; Save R10 |
| addq 4, $acr |
| move.d $r11, [$acr] ; Save R11 |
| addq 4, $acr |
| move.d $r12, [$acr] ; Save R12 |
| addq 4, $acr |
| move.d $r13, [$acr] ; Save R13 |
| addq 4, $acr |
| move.d $sp, [$acr] ; Save SP (R14) |
| addq 4, $acr |
| |
| ;; The ACR register is already saved on the stack, so pop it from there. |
| move.d [$sp],$r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| |
| move $bz, [$acr] |
| addq 1, $acr |
| move $vr, [$acr] |
| addq 1, $acr |
| move $pid, [$acr] |
| addq 4, $acr |
| move $srs, [$acr] |
| addq 1, $acr |
| move $wz, [$acr] |
| addq 2, $acr |
| move $exs, [$acr] |
| addq 4, $acr |
| move $eda, [$acr] |
| addq 4, $acr |
| move $mof, [$acr] |
| addq 4, $acr |
| move $dz, [$acr] |
| addq 4, $acr |
| move $ebp, [$acr] |
| addq 4, $acr |
| move $erp, [$acr] |
| addq 4, $acr |
| move $srp, [$acr] |
| addq 4, $acr |
| move $nrp, [$acr] |
| addq 4, $acr |
| move $ccs, [$acr] |
| addq 4, $acr |
| move $usp, [$acr] |
| addq 4, $acr |
| move $spc, [$acr] |
| addq 4, $acr |
| |
| ;; Skip the pseudo-PC. |
| addq 4, $acr |
| |
| ;; Save the support registers in bank 0 - 3. |
| clear.d $r1 ; Bank counter |
| move.d sreg, $acr |
| |
| ;; Bank 0 |
| move $r1, $srs |
| nop |
| nop |
| nop |
| move $s0, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s1, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s2, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s3, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s4, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s5, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s6, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s7, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s8, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s9, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s10, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s11, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s12, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| |
| ;; Nothing in S13 - S15, bank 0 |
| clear.d [$acr] |
| addq 4, $acr |
| clear.d [$acr] |
| addq 4, $acr |
| clear.d [$acr] |
| addq 4, $acr |
| |
| ;; Bank 1 and bank 2 have the same layout, hence the loop. |
| addq 1, $r1 |
| 1: |
| move $r1, $srs |
| nop |
| nop |
| nop |
| move $s0, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s1, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s2, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s3, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s4, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s5, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s6, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| |
| ;; Nothing in S7 - S15, bank 1 and 2 |
| clear.d [$acr] |
| addq 4, $acr |
| clear.d [$acr] |
| addq 4, $acr |
| clear.d [$acr] |
| addq 4, $acr |
| clear.d [$acr] |
| addq 4, $acr |
| clear.d [$acr] |
| addq 4, $acr |
| clear.d [$acr] |
| addq 4, $acr |
| clear.d [$acr] |
| addq 4, $acr |
| clear.d [$acr] |
| addq 4, $acr |
| clear.d [$acr] |
| addq 4, $acr |
| |
| addq 1, $r1 |
| cmpq 3, $r1 |
| bne 1b |
| nop |
| |
| ;; Bank 3 |
| move $r1, $srs |
| nop |
| nop |
| nop |
| move $s0, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s1, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s2, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s3, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s4, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s5, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s6, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s7, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s8, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s9, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s10, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s11, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s12, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s13, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| move $s14, $r0 |
| move.d $r0, [$acr] |
| addq 4, $acr |
| ;; Nothing in S15, bank 3 |
| clear.d [$acr] |
| addq 4, $acr |
| |
| ;; Check what got us here: get IDX field of EXS. |
| move $exs, $r10 |
| and.d 0xff00, $r10 |
| lsrq 8, $r10 |
| #if defined(CONFIG_ETRAX_KGDB_PORT0) |
| cmp.d SER0_INTR_VECT, $r10 ; IRQ for serial port 0 |
| beq sigint |
| nop |
| #elif defined(CONFIG_ETRAX_KGDB_PORT1) |
| cmp.d SER1_INTR_VECT, $r10 ; IRQ for serial port 1 |
| beq sigint |
| nop |
| #elif defined(CONFIG_ETRAX_KGDB_PORT2) |
| cmp.d SER2_INTR_VECT, $r10 ; IRQ for serial port 2 |
| beq sigint |
| nop |
| #elif defined(CONFIG_ETRAX_KGDB_PORT3) |
| cmp.d SER3_INTR_VECT, $r10 ; IRQ for serial port 3 |
| beq sigint |
| nop |
| #endif |
| ;; Multiple interrupt must be due to serial break. |
| cmp.d 0x30, $r10 ; Multiple interrupt |
| beq sigint |
| nop |
| ;; Neither of those? Then it's a sigtrap. |
| ba handle_comm |
| moveq 5, $r10 ; Set SIGTRAP (delay slot) |
| |
| sigint: |
| ;; Serial interrupt; get character |
| jsr getDebugChar |
| nop ; Delay slot |
| cmp.b 3, $r10 ; \003 (Ctrl-C)? |
| bne return ; No, get out of here |
| nop |
| moveq 2, $r10 ; Set SIGINT |
| |
| ;; |
| ;; Handle the communication |
| ;; |
| handle_comm: |
| move.d internal_stack+1020, $sp ; Use the internal stack which grows upwards |
| jsr handle_exception ; Interactive routine |
| nop |
| |
| ;; |
| ;; Return to the caller |
| ;; |
| return: |
| |
| ;; First of all, write the support registers. |
| clear.d $r1 ; Bank counter |
| move.d sreg, $acr |
| |
| ;; Bank 0 |
| move $r1, $srs |
| nop |
| nop |
| nop |
| move.d [$acr], $r0 |
| move $r0, $s0 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s1 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s2 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s3 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s4 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s5 |
| addq 4, $acr |
| |
| ;; Nothing in S6 - S7, bank 0. |
| addq 4, $acr |
| addq 4, $acr |
| |
| move.d [$acr], $r0 |
| move $r0, $s8 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s9 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s10 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s11 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s12 |
| addq 4, $acr |
| |
| ;; Nothing in S13 - S15, bank 0 |
| addq 4, $acr |
| addq 4, $acr |
| addq 4, $acr |
| |
| ;; Bank 1 and bank 2 have the same layout, hence the loop. |
| addq 1, $r1 |
| 2: |
| move $r1, $srs |
| nop |
| nop |
| nop |
| move.d [$acr], $r0 |
| move $r0, $s0 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s1 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s2 |
| addq 4, $acr |
| |
| ;; S3 (MM_CAUSE) is read-only. |
| addq 4, $acr |
| |
| move.d [$acr], $r0 |
| move $r0, $s4 |
| addq 4, $acr |
| |
| ;; FIXME: Actually write S5/S6? (Affects MM_CAUSE.) |
| addq 4, $acr |
| addq 4, $acr |
| |
| ;; Nothing in S7 - S15, bank 1 and 2 |
| addq 4, $acr |
| addq 4, $acr |
| addq 4, $acr |
| addq 4, $acr |
| addq 4, $acr |
| addq 4, $acr |
| addq 4, $acr |
| addq 4, $acr |
| addq 4, $acr |
| |
| addq 1, $r1 |
| cmpq 3, $r1 |
| bne 2b |
| nop |
| |
| ;; Bank 3 |
| move $r1, $srs |
| nop |
| nop |
| nop |
| move.d [$acr], $r0 |
| move $r0, $s0 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s1 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s2 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s3 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s4 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s5 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s6 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s7 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s8 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s9 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s10 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s11 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s12 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s13 |
| addq 4, $acr |
| move.d [$acr], $r0 |
| move $r0, $s14 |
| addq 4, $acr |
| |
| ;; Nothing in S15, bank 3 |
| addq 4, $acr |
| |
| ;; Now, move on to the regular register restoration process. |
| |
| move.d reg, $acr ; Reset ACR to point at the beginning of the register image |
| move.d [$acr], $r0 ; Restore R0 |
| addq 4, $acr |
| move.d [$acr], $r1 ; Restore R1 |
| addq 4, $acr |
| move.d [$acr], $r2 ; Restore R2 |
| addq 4, $acr |
| move.d [$acr], $r3 ; Restore R3 |
| addq 4, $acr |
| move.d [$acr], $r4 ; Restore R4 |
| addq 4, $acr |
| move.d [$acr], $r5 ; Restore R5 |
| addq 4, $acr |
| move.d [$acr], $r6 ; Restore R6 |
| addq 4, $acr |
| move.d [$acr], $r7 ; Restore R7 |
| addq 4, $acr |
| move.d [$acr], $r8 ; Restore R8 |
| addq 4, $acr |
| move.d [$acr], $r9 ; Restore R9 |
| addq 4, $acr |
| move.d [$acr], $r10 ; Restore R10 |
| addq 4, $acr |
| move.d [$acr], $r11 ; Restore R11 |
| addq 4, $acr |
| move.d [$acr], $r12 ; Restore R12 |
| addq 4, $acr |
| move.d [$acr], $r13 ; Restore R13 |
| |
| ;; |
| ;; We restore all registers, even though some of them probably haven't changed. |
| ;; |
| |
| addq 4, $acr |
| move.d [$acr], $sp ; Restore SP (R14) |
| |
| ;; ACR cannot be restored just yet. |
| addq 8, $acr |
| |
| ;; Skip BZ, VR. |
| addq 2, $acr |
| |
| move [$acr], $pid ; Restore PID |
| addq 4, $acr |
| move [$acr], $srs ; Restore SRS |
| nop |
| nop |
| nop |
| addq 1, $acr |
| |
| ;; Skip WZ. |
| addq 2, $acr |
| |
| move [$acr], $exs ; Restore EXS. |
| addq 4, $acr |
| move [$acr], $eda ; Restore EDA. |
| addq 4, $acr |
| move [$acr], $mof ; Restore MOF. |
| |
| ;; Skip DZ. |
| addq 8, $acr |
| |
| move [$acr], $ebp ; Restore EBP. |
| addq 4, $acr |
| move [$acr], $erp ; Restore ERP. |
| addq 4, $acr |
| move [$acr], $srp ; Restore SRP. |
| addq 4, $acr |
| move [$acr], $nrp ; Restore NRP. |
| addq 4, $acr |
| move [$acr], $ccs ; Restore CCS like an ordinary register. |
| addq 4, $acr |
| move [$acr], $usp ; Restore USP |
| addq 4, $acr |
| move [$acr], $spc ; Restore SPC |
| ; No restoration of pseudo-PC of course. |
| |
| move.d reg, $acr ; Reset ACR to point at the beginning of the register image |
| add.d 15*4, $acr |
| move.d [$acr], $acr ; Finally, restore ACR. |
| rete ; Same as jump ERP |
| rfe ; Shifts CCS |
