diff options
Diffstat (limited to 'target/openrisc/mmu.c')
| -rw-r--r-- | target/openrisc/mmu.c | 238 |
1 files changed, 238 insertions, 0 deletions
diff --git a/target/openrisc/mmu.c b/target/openrisc/mmu.c new file mode 100644 index 0000000000..505dcdcdc8 --- /dev/null +++ b/target/openrisc/mmu.c @@ -0,0 +1,238 @@ +/* + * OpenRISC MMU. + * + * Copyright (c) 2011-2012 Jia Liu <proljc@gmail.com> + * Zhizhou Zhang <etouzh@gmail.com> + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, see <http://www.gnu.org/licenses/>. + */ + +#include "qemu/osdep.h" +#include "cpu.h" +#include "exec/exec-all.h" +#include "qemu-common.h" +#include "exec/gdbstub.h" +#include "qemu/host-utils.h" +#ifndef CONFIG_USER_ONLY +#include "hw/loader.h" +#endif + +#ifndef CONFIG_USER_ONLY +int cpu_openrisc_get_phys_nommu(OpenRISCCPU *cpu, + hwaddr *physical, + int *prot, target_ulong address, int rw) +{ + *physical = address; + *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC; + return TLBRET_MATCH; +} + +int cpu_openrisc_get_phys_code(OpenRISCCPU *cpu, + hwaddr *physical, + int *prot, target_ulong address, int rw) +{ + int vpn = address >> TARGET_PAGE_BITS; + int idx = vpn & ITLB_MASK; + int right = 0; + + if ((cpu->env.tlb->itlb[0][idx].mr >> TARGET_PAGE_BITS) != vpn) { + return TLBRET_NOMATCH; + } + if (!(cpu->env.tlb->itlb[0][idx].mr & 1)) { + return TLBRET_INVALID; + } + + if (cpu->env.sr & SR_SM) { /* supervisor mode */ + if (cpu->env.tlb->itlb[0][idx].tr & SXE) { + right |= PAGE_EXEC; + } + } else { + if (cpu->env.tlb->itlb[0][idx].tr & UXE) { + right |= PAGE_EXEC; + } + } + + if ((rw & 2) && ((right & PAGE_EXEC) == 0)) { + return TLBRET_BADADDR; + } + + *physical = (cpu->env.tlb->itlb[0][idx].tr & TARGET_PAGE_MASK) | + (address & (TARGET_PAGE_SIZE-1)); + *prot = right; + return TLBRET_MATCH; +} + +int cpu_openrisc_get_phys_data(OpenRISCCPU *cpu, + hwaddr *physical, + int *prot, target_ulong address, int rw) +{ + int vpn = address >> TARGET_PAGE_BITS; + int idx = vpn & DTLB_MASK; + int right = 0; + + if ((cpu->env.tlb->dtlb[0][idx].mr >> TARGET_PAGE_BITS) != vpn) { + return TLBRET_NOMATCH; + } + if (!(cpu->env.tlb->dtlb[0][idx].mr & 1)) { + return TLBRET_INVALID; + } + + if (cpu->env.sr & SR_SM) { /* supervisor mode */ + if (cpu->env.tlb->dtlb[0][idx].tr & SRE) { + right |= PAGE_READ; + } + if (cpu->env.tlb->dtlb[0][idx].tr & SWE) { + right |= PAGE_WRITE; + } + } else { + if (cpu->env.tlb->dtlb[0][idx].tr & URE) { + right |= PAGE_READ; + } + if (cpu->env.tlb->dtlb[0][idx].tr & UWE) { + right |= PAGE_WRITE; + } + } + + if (!(rw & 1) && ((right & PAGE_READ) == 0)) { + return TLBRET_BADADDR; + } + if ((rw & 1) && ((right & PAGE_WRITE) == 0)) { + return TLBRET_BADADDR; + } + + *physical = (cpu->env.tlb->dtlb[0][idx].tr & TARGET_PAGE_MASK) | + (address & (TARGET_PAGE_SIZE-1)); + *prot = right; + return TLBRET_MATCH; +} + +static int cpu_openrisc_get_phys_addr(OpenRISCCPU *cpu, + hwaddr *physical, + int *prot, target_ulong address, + int rw) +{ + int ret = TLBRET_MATCH; + + if (rw == 2) { /* ITLB */ + *physical = 0; + ret = cpu->env.tlb->cpu_openrisc_map_address_code(cpu, physical, + prot, address, rw); + } else { /* DTLB */ + ret = cpu->env.tlb->cpu_openrisc_map_address_data(cpu, physical, + prot, address, rw); + } + + return ret; +} +#endif + +static void cpu_openrisc_raise_mmu_exception(OpenRISCCPU *cpu, + target_ulong address, + int rw, int tlb_error) +{ + CPUState *cs = CPU(cpu); + int exception = 0; + + switch (tlb_error) { + default: + if (rw == 2) { + exception = EXCP_IPF; + } else { + exception = EXCP_DPF; + } + break; +#ifndef CONFIG_USER_ONLY + case TLBRET_BADADDR: + if (rw == 2) { + exception = EXCP_IPF; + } else { + exception = EXCP_DPF; + } + break; + case TLBRET_INVALID: + case TLBRET_NOMATCH: + /* No TLB match for a mapped address */ + if (rw == 2) { + exception = EXCP_ITLBMISS; + } else { + exception = EXCP_DTLBMISS; + } + break; +#endif + } + + cs->exception_index = exception; + cpu->env.eear = address; +} + +#ifndef CONFIG_USER_ONLY +int openrisc_cpu_handle_mmu_fault(CPUState *cs, + vaddr address, int rw, int mmu_idx) +{ + OpenRISCCPU *cpu = OPENRISC_CPU(cs); + int ret = 0; + hwaddr physical = 0; + int prot = 0; + + ret = cpu_openrisc_get_phys_addr(cpu, &physical, &prot, + address, rw); + + if (ret == TLBRET_MATCH) { + tlb_set_page(cs, address & TARGET_PAGE_MASK, + physical & TARGET_PAGE_MASK, prot, + mmu_idx, TARGET_PAGE_SIZE); + ret = 0; + } else if (ret < 0) { + cpu_openrisc_raise_mmu_exception(cpu, address, rw, ret); + ret = 1; + } + + return ret; +} +#else +int openrisc_cpu_handle_mmu_fault(CPUState *cs, + vaddr address, int rw, int mmu_idx) +{ + OpenRISCCPU *cpu = OPENRISC_CPU(cs); + int ret = 0; + + cpu_openrisc_raise_mmu_exception(cpu, address, rw, ret); + ret = 1; + + return ret; +} +#endif + +#ifndef CONFIG_USER_ONLY +hwaddr openrisc_cpu_get_phys_page_debug(CPUState *cs, vaddr addr) +{ + OpenRISCCPU *cpu = OPENRISC_CPU(cs); + hwaddr phys_addr; + int prot; + + if (cpu_openrisc_get_phys_addr(cpu, &phys_addr, &prot, addr, 0)) { + return -1; + } + + return phys_addr; +} + +void cpu_openrisc_mmu_init(OpenRISCCPU *cpu) +{ + cpu->env.tlb = g_malloc0(sizeof(CPUOpenRISCTLBContext)); + + cpu->env.tlb->cpu_openrisc_map_address_code = &cpu_openrisc_get_phys_nommu; + cpu->env.tlb->cpu_openrisc_map_address_data = &cpu_openrisc_get_phys_nommu; +} +#endif |