diff options
| -rw-r--r-- | src/arch/riscv/include/arch/exception.h | 2 | ||||
| -rw-r--r-- | src/arch/riscv/trap_handler.c | 29 | ||||
| -rw-r--r-- | src/arch/riscv/trap_util.S | 2 |
3 files changed, 31 insertions, 2 deletions
diff --git a/src/arch/riscv/include/arch/exception.h b/src/arch/riscv/include/arch/exception.h index 4318cba8b6..28b9279707 100644 --- a/src/arch/riscv/include/arch/exception.h +++ b/src/arch/riscv/include/arch/exception.h @@ -55,7 +55,7 @@ static inline void exception_init(void) void trap_handler(trapframe* tf); void handle_supervisor_call(trapframe* tf); -//void handleMisalignedLoad(trapframe *tf); +void handleMisalignedLoad(trapframe *tf); void handle_misaligned_store(trapframe *tf); #endif diff --git a/src/arch/riscv/trap_handler.c b/src/arch/riscv/trap_handler.c index d4c9b87352..61480379b2 100644 --- a/src/arch/riscv/trap_handler.c +++ b/src/arch/riscv/trap_handler.c @@ -162,6 +162,35 @@ void trap_handler(trapframe *tf) { while(1); } +void handleMisalignedLoad(trapframe *tf) { + printk(BIOS_DEBUG, "Trapframe ptr: %p\n", tf); + printk(BIOS_DEBUG, "Stored sp: %p\n", (void*) tf->gpr[2]); + insn_t faultingInstruction = 0; + uintptr_t faultingInstructionAddr = tf->epc; + asm("move t0, %0" : /* No outputs */ : "r"(faultingInstructionAddr)); + asm("lw t0, 0(t0)"); + asm("move %0, t0" : "=r"(faultingInstruction)); + printk(BIOS_DEBUG, "Faulting instruction: 0x%x\n", faultingInstruction); + insn_t widthMask = 0x7000; + insn_t memWidth = (faultingInstruction & widthMask) >> 12; + insn_t destMask = 0xF80; + insn_t destRegister = (faultingInstruction & destMask) >> 7; + printk(BIOS_DEBUG, "Width: 0x%x\n", memWidth); + if (memWidth == 3) { + // load double, handle the issue + void* badAddress = (void*) tf->badvaddr; + memcpy(&(tf->gpr[destRegister]), badAddress, 8); + } else { + // panic, this should not have happened + printk(BIOS_DEBUG, "Code should not reach this path, misaligned on a non-64 bit store/load\n"); + while(1); + } + + // return to where we came from + write_csr(mepc, read_csr(mepc) + 4); + asm volatile("j machine_call_return"); +} + void handle_misaligned_store(trapframe *tf) { printk(BIOS_DEBUG, "Trapframe ptr: %p\n", tf); printk(BIOS_DEBUG, "Stored sp: %p\n", (void*) tf->gpr[2]); diff --git a/src/arch/riscv/trap_util.S b/src/arch/riscv/trap_util.S index 9701aaf1f6..274dca6960 100644 --- a/src/arch/riscv/trap_util.S +++ b/src/arch/riscv/trap_util.S @@ -112,7 +112,7 @@ supervisor_trap_entry: csrw mscratch, sp # load in the top of the machine stack - la sp, 0x80FFF0 + la sp, 0x80FFF0 - 64 1:addi sp,sp,-320 save_tf move a0,sp |