if (!proc->state.dcsr.cause && get_field(proc->state.mstatus, MSTATUS_MPRV))
mode = get_field(proc->state.mstatus, MSTATUS_MPP);
}
- if (get_field(proc->state.mstatus, MSTATUS_VM) == VM_MBARE)
- mode = PRV_M;
- if (mode == PRV_M) {
- reg_t msb_mask = (reg_t(2) << (proc->xlen-1))-1; // zero-extend from xlen
- return addr & msb_mask;
- }
return walk(addr, type, mode) | (addr & (PGSIZE-1));
}
{
reg_t paddr = translate(vaddr, FETCH);
- // mmu_t::walk() returns -1 if it can't find a match. Of course -1 could also
- // be a valid address.
- if (paddr == ~(reg_t) 0 && vaddr != ~(reg_t) 0) {
- throw trap_instruction_access_fault(vaddr);
- }
-
if (sim->addr_is_mem(paddr)) {
refill_tlb(vaddr, paddr, FETCH);
return (const uint16_t*)sim->addr_to_mem(paddr);
}
}
+reg_t reg_from_bytes(size_t len, const uint8_t* bytes)
+{
+ switch (len) {
+ case 1:
+ return bytes[0];
+ case 2:
+ return bytes[0] |
+ (((reg_t) bytes[1]) << 8);
+ case 4:
+ return bytes[0] |
+ (((reg_t) bytes[1]) << 8) |
+ (((reg_t) bytes[2]) << 16) |
+ (((reg_t) bytes[3]) << 24);
+ case 8:
+ return bytes[0] |
+ (((reg_t) bytes[1]) << 8) |
+ (((reg_t) bytes[2]) << 16) |
+ (((reg_t) bytes[3]) << 24) |
+ (((reg_t) bytes[4]) << 32) |
+ (((reg_t) bytes[5]) << 40) |
+ (((reg_t) bytes[6]) << 48) |
+ (((reg_t) bytes[7]) << 56);
+ }
+ abort();
+}
+
void mmu_t::load_slow_path(reg_t addr, reg_t len, uint8_t* bytes)
{
reg_t paddr = translate(addr, LOAD);
+
if (sim->addr_is_mem(paddr)) {
memcpy(bytes, sim->addr_to_mem(paddr), len);
if (tracer.interested_in_range(paddr, paddr + PGSIZE, LOAD))
} else if (!sim->mmio_load(paddr, len, bytes)) {
throw trap_load_access_fault(addr);
}
+
+ if (!matched_trigger) {
+ reg_t data = reg_from_bytes(len, bytes);
+ matched_trigger = trigger_exception(OPERATION_LOAD, addr, data);
+ if (matched_trigger)
+ throw *matched_trigger;
+ }
}
void mmu_t::store_slow_path(reg_t addr, reg_t len, const uint8_t* bytes)
{
reg_t paddr = translate(addr, STORE);
+
+ if (!matched_trigger) {
+ reg_t data = reg_from_bytes(len, bytes);
+ matched_trigger = trigger_exception(OPERATION_STORE, addr, data);
+ if (matched_trigger)
+ throw *matched_trigger;
+ }
+
if (sim->addr_is_mem(paddr)) {
memcpy(sim->addr_to_mem(paddr), bytes, len);
if (tracer.interested_in_range(paddr, paddr + PGSIZE, STORE))
reg_t mmu_t::walk(reg_t addr, access_type type, reg_t mode)
{
- int levels, ptidxbits, ptesize;
- switch (get_field(proc->get_state()->mstatus, MSTATUS_VM))
- {
- case VM_SV32: levels = 2; ptidxbits = 10; ptesize = 4; break;
- case VM_SV39: levels = 3; ptidxbits = 9; ptesize = 8; break;
- case VM_SV48: levels = 4; ptidxbits = 9; ptesize = 8; break;
- default: abort();
- }
+ vm_info vm = decode_vm_info(proc->max_xlen, mode, proc->get_state()->sptbr);
+ if (vm.levels == 0)
+ return addr & ((reg_t(2) << (proc->xlen-1))-1); // zero-extend from xlen
bool supervisor = mode == PRV_S;
- bool pum = get_field(proc->state.mstatus, MSTATUS_PUM);
+ bool sum = get_field(proc->state.mstatus, MSTATUS_SUM);
bool mxr = get_field(proc->state.mstatus, MSTATUS_MXR);
// verify bits xlen-1:va_bits-1 are all equal
- int va_bits = PGSHIFT + levels * ptidxbits;
+ int va_bits = PGSHIFT + vm.levels * vm.idxbits;
reg_t mask = (reg_t(1) << (proc->xlen - (va_bits-1))) - 1;
reg_t masked_msbs = (addr >> (va_bits-1)) & mask;
if (masked_msbs != 0 && masked_msbs != mask)
- return -1;
+ vm.levels = 0;
- reg_t base = proc->get_state()->sptbr << PGSHIFT;
- int ptshift = (levels - 1) * ptidxbits;
- for (int i = 0; i < levels; i++, ptshift -= ptidxbits) {
- reg_t idx = (addr >> (PGSHIFT + ptshift)) & ((1 << ptidxbits) - 1);
+ reg_t base = vm.ptbase;
+ for (int i = vm.levels - 1; i >= 0; i--) {
+ int ptshift = i * vm.idxbits;
+ reg_t idx = (addr >> (PGSHIFT + ptshift)) & ((1 << vm.idxbits) - 1);
// check that physical address of PTE is legal
- reg_t pte_addr = base + idx * ptesize;
+ reg_t pte_addr = base + idx * vm.ptesize;
if (!sim->addr_is_mem(pte_addr))
- break;
+ throw trap_load_access_fault(addr);
void* ppte = sim->addr_to_mem(pte_addr);
- reg_t pte = ptesize == 4 ? *(uint32_t*)ppte : *(uint64_t*)ppte;
+ reg_t pte = vm.ptesize == 4 ? *(uint32_t*)ppte : *(uint64_t*)ppte;
reg_t ppn = pte >> PTE_PPN_SHIFT;
if (PTE_TABLE(pte)) { // next level of page table
base = ppn << PGSHIFT;
- } else if ((pte & PTE_U) ? supervisor && pum : !supervisor) {
+ } else if ((pte & PTE_U) ? supervisor && !sum : !supervisor) {
break;
} else if (!(pte & PTE_V) || (!(pte & PTE_R) && (pte & PTE_W))) {
break;
!((pte & PTE_R) && (pte & PTE_W))) {
break;
} else {
+ reg_t ad = PTE_A | ((type == STORE) * PTE_D);
+#ifdef RISCV_ENABLE_DIRTY
// set accessed and possibly dirty bits.
- *(uint32_t*)ppte |= PTE_A | ((type == STORE) * PTE_D);
+ *(uint32_t*)ppte |= ad;
+#else
+ // take exception if access or possibly dirty bit is not set.
+ if ((pte & ad) != ad)
+ break;
+#endif
// for superpage mappings, make a fake leaf PTE for the TLB's benefit.
reg_t vpn = addr >> PGSHIFT;
reg_t value = (ppn | (vpn & ((reg_t(1) << ptshift) - 1))) << PGSHIFT;
}
}
- return -1;
+fail:
+ switch (type) {
+ case FETCH: throw trap_instruction_page_fault(addr);
+ case LOAD: throw trap_load_page_fault(addr);
+ case STORE: throw trap_store_page_fault(addr);
+ default: abort();
+ }
}
void mmu_t::register_memtracer(memtracer_t* t)