/*
* ARM TLB (Translation lookaside buffer) helpers.
*
* This code is licensed under the GNU GPL v2 or later.
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "qemu/osdep.h"
#include "cpu.h"
#include "internals.h"
#include "exec/exec-all.h"
#if !defined(CONFIG_USER_ONLY)
static inline uint32_t merge_syn_data_abort(uint32_t template_syn,
unsigned int target_el,
bool same_el, bool ea,
bool s1ptw, bool is_write,
int fsc)
{
uint32_t syn;
/*
* ISV is only set for data aborts routed to EL2 and
* never for stage-1 page table walks faulting on stage 2.
*
* Furthermore, ISV is only set for certain kinds of load/stores.
* If the template syndrome does not have ISV set, we should leave
* it cleared.
*
* See ARMv8 specs, D7-1974:
* ISS encoding for an exception from a Data Abort, the
* ISV field.
*/
if (!(template_syn & ARM_EL_ISV) || target_el != 2 || s1ptw) {
syn = syn_data_abort_no_iss(same_el,
ea, 0, s1ptw, is_write, fsc);
} else {
/*
* Fields: IL, ISV, SAS, SSE, SRT, SF and AR come from the template
* syndrome created at translation time.
* Now we create the runtime syndrome with the remaining fields.
*/
syn = syn_data_abort_with_iss(same_el,
0, 0, 0, 0, 0,
ea, 0, s1ptw, is_write, fsc,
true);
/* Merge the runtime syndrome with the template syndrome. */
syn |= template_syn;
}
return syn;
}
static void QEMU_NORETURN arm_deliver_fault(ARMCPU *cpu, vaddr addr,
MMUAccessType access_type,
int mmu_idx, ARMMMUFaultInfo *fi)
{
CPUARMState *env = &cpu->env;
int target_el;
bool same_el;
uint32_t syn, exc, fsr, fsc;
ARMMMUIdx arm_mmu_idx = core_to_arm_mmu_idx(env, mmu_idx);
target_el = exception_target_el(env);
if (fi->stage2) {
target_el = 2;
env->cp15.hpfar_el2 = extract64(fi->s2addr, 12, 47) << 4;
}
same_el = (arm_current_el(env) == target_el);
if (target_el == 2 || arm_el_is_aa64(env, target_el) ||
arm_s1_regime_using_lpae_format(env, arm_mmu_idx)) {
/*
* LPAE format fault status register : bottom 6 bits are
* status code in the same form as needed for syndrome
*/
fsr = arm_fi_to_lfsc(fi);
fsc = extract32(fsr, 0, 6);
} else {
fsr = arm_fi_to_sfsc(fi);
/*
* Short format FSR : this fault will never actually be reported
* to an EL that uses a syndrome register. Use a (currently)
* reserved FSR code in case the constructed syndrome does leak
* into the guest somehow.
*/
fsc = 0x3f;
}
if (access_type == MMU_INST_FETCH) {
syn = syn_insn_abort(same_el, fi->ea, fi->s1ptw, fsc);
exc = EXCP_PREFETCH_ABORT;
} else {
syn = merge_syn_data_abort(env->exception.syndrome, target_el,
same_el, fi->ea, fi->s1ptw,
access_type == MMU_DATA_STORE,
fsc);
if (access_type == MMU_DATA_STORE
&& arm_feature(env, ARM_FEATURE_V6)) {
fsr |= (1 << 11);
}
exc = EXCP_DATA_ABORT;
}
env->exception.vaddress = addr;
env->exception.fsr = fsr;
raise_exception(env, exc, syn, target_el);
}
/* Raise a data fault alignment exception for the specified virtual address */
void arm_cpu_do_unaligned_access(CPUState *cs, vaddr vaddr,
MMUAccessType access_type,
int mmu_idx, uintptr_t retaddr)
{
ARMCPU *cpu = ARM_CPU(cs);
ARMMMUFaultInfo fi = {};
/* now we have a real cpu fault */
cpu_restore_state(cs, retaddr, true);
fi.type = ARMFault_Alignment;
arm_deliver_fault(cpu, vaddr, access_type, mmu_idx, &fi);
}
/*
* arm_cpu_do_transaction_failed: handle a memory system error response
* (eg "no device/memory present at address") by raising an external abort
* exception
*/
void arm_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
vaddr addr, unsigned size,
MMUAccessType access_type,
int mmu_idx, MemTxAttrs attrs,
MemTxResult response, uintptr_t retaddr)
{
ARMCPU *cpu = ARM_CPU(cs);
ARMMMUFaultInfo fi = {};
/* now we have a real cpu fault */
cpu_restore_state(cs, retaddr, true);
fi.ea = arm_extabort_type(response);
fi.type = ARMFault_SyncExternal;
arm_deliver_fault(cpu, addr, access_type, mmu_idx, &fi);
}
#endif /* !defined(CONFIG_USER_ONLY) */
bool arm_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
MMUAccessType access_type, int mmu_idx,
bool probe, uintptr_t retaddr)
{
ARMCPU *cpu = ARM_CPU(cs);
#ifdef CONFIG_USER_ONLY
cpu->env.exception.vaddress = address;
if (access_type == MMU_INST_FETCH) {
cs->exception_index = EXCP_PREFETCH_ABORT;
} else {
cs->exception_index = EXCP_DATA_ABORT;
}
cpu_loop_exit_restore(cs, retaddr);
#else
hwaddr phys_addr;
target_ulong page_size;
int prot, ret;
MemTxAttrs attrs = {};
ARMMMUFaultInfo fi = {};
/*
* Walk the page table and (if the mapping exists) add the page
* to the TLB. On success, return true. Otherwise, if probing,
* return false. Otherwise populate fsr with ARM DFSR/IFSR fault
* register format, and signal the fault.
*/
ret = get_phys_addr(&cpu->env, address, access_type,
core_to_arm_mmu_idx(&cpu->env, mmu_idx),
&phys_addr, &attrs, &prot, &page_size, &fi, NULL);
if (likely(!ret)) {
/*
* Map a single [sub]page. Regions smaller than our declared
* target page size are handled specially, so for those we
* pass in the exact addresses.
*/
if (page_size >= TARGET_PAGE_SIZE) {
phys_addr &= TARGET_PAGE_MASK;
address &= TARGET_PAGE_MASK;
}
tlb_set_page_with_attrs(cs, address, phys_addr, attrs,
prot, mmu_idx, page_size);
return true;
} else if (probe) {
return false;
} else {
/* now we have a real cpu fault */
cpu_restore_state(cs, retaddr, true);
arm_deliver_fault(cpu, address, access_type, mmu_idx, &fi);
}
#endif
}
