diff options
Diffstat (limited to 'arch/arm/kvm/coproc.c')
| -rw-r--r-- | arch/arm/kvm/coproc.c | 360 |
1 files changed, 360 insertions, 0 deletions
diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c index 0c433558591c..722efe3b1675 100644 --- a/arch/arm/kvm/coproc.c +++ b/arch/arm/kvm/coproc.c @@ -16,8 +16,368 @@ * along with this program; if not, write to the Free Software * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ +#include <linux/mm.h> #include <linux/kvm_host.h> +#include <asm/kvm_arm.h> +#include <asm/kvm_host.h> +#include <asm/kvm_emulate.h> +#include <asm/kvm_coproc.h> +#include <asm/cacheflush.h> +#include <asm/cputype.h> +#include <trace/events/kvm.h> +#include "trace.h" +#include "coproc.h" + + +/****************************************************************************** + * Co-processor emulation + *****************************************************************************/ + +int kvm_handle_cp10_id(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + kvm_inject_undefined(vcpu); + return 1; +} + +int kvm_handle_cp_0_13_access(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + /* + * We can get here, if the host has been built without VFPv3 support, + * but the guest attempted a floating point operation. + */ + kvm_inject_undefined(vcpu); + return 1; +} + +int kvm_handle_cp14_load_store(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + kvm_inject_undefined(vcpu); + return 1; +} + +int kvm_handle_cp14_access(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + kvm_inject_undefined(vcpu); + return 1; +} + +/* See note at ARM ARM B1.14.4 */ +static bool access_dcsw(struct kvm_vcpu *vcpu, + const struct coproc_params *p, + const struct coproc_reg *r) +{ + u32 val; + int cpu; + + cpu = get_cpu(); + + if (!p->is_write) + return read_from_write_only(vcpu, p); + + cpumask_setall(&vcpu->arch.require_dcache_flush); + cpumask_clear_cpu(cpu, &vcpu->arch.require_dcache_flush); + + /* If we were already preempted, take the long way around */ + if (cpu != vcpu->arch.last_pcpu) { + flush_cache_all(); + goto done; + } + + val = *vcpu_reg(vcpu, p->Rt1); + + switch (p->CRm) { + case 6: /* Upgrade DCISW to DCCISW, as per HCR.SWIO */ + case 14: /* DCCISW */ + asm volatile("mcr p15, 0, %0, c7, c14, 2" : : "r" (val)); + break; + + case 10: /* DCCSW */ + asm volatile("mcr p15, 0, %0, c7, c10, 2" : : "r" (val)); + break; + } + +done: + put_cpu(); + + return true; +} + +/* + * We could trap ID_DFR0 and tell the guest we don't support performance + * monitoring. Unfortunately the patch to make the kernel check ID_DFR0 was + * NAKed, so it will read the PMCR anyway. + * + * Therefore we tell the guest we have 0 counters. Unfortunately, we + * must always support PMCCNTR (the cycle counter): we just RAZ/WI for + * all PM registers, which doesn't crash the guest kernel at least. + */ +static bool pm_fake(struct kvm_vcpu *vcpu, + const struct coproc_params *p, + const struct coproc_reg *r) +{ + if (p->is_write) + return ignore_write(vcpu, p); + else + return read_zero(vcpu, p); +} + +#define access_pmcr pm_fake +#define access_pmcntenset pm_fake +#define access_pmcntenclr pm_fake +#define access_pmovsr pm_fake +#define access_pmselr pm_fake +#define access_pmceid0 pm_fake +#define access_pmceid1 pm_fake +#define access_pmccntr pm_fake +#define access_pmxevtyper pm_fake +#define access_pmxevcntr pm_fake +#define access_pmuserenr pm_fake +#define access_pmintenset pm_fake +#define access_pmintenclr pm_fake + +/* Architected CP15 registers. + * Important: Must be sorted ascending by CRn, CRM, Op1, Op2 + */ +static const struct coproc_reg cp15_regs[] = { + /* CSSELR: swapped by interrupt.S. */ + { CRn( 0), CRm( 0), Op1( 2), Op2( 0), is32, + NULL, reset_unknown, c0_CSSELR }, + + /* TTBR0/TTBR1: swapped by interrupt.S. */ + { CRm( 2), Op1( 0), is64, NULL, reset_unknown64, c2_TTBR0 }, + { CRm( 2), Op1( 1), is64, NULL, reset_unknown64, c2_TTBR1 }, + + /* TTBCR: swapped by interrupt.S. */ + { CRn( 2), CRm( 0), Op1( 0), Op2( 2), is32, + NULL, reset_val, c2_TTBCR, 0x00000000 }, + + /* DACR: swapped by interrupt.S. */ + { CRn( 3), CRm( 0), Op1( 0), Op2( 0), is32, + NULL, reset_unknown, c3_DACR }, + + /* DFSR/IFSR/ADFSR/AIFSR: swapped by interrupt.S. */ + { CRn( 5), CRm( 0), Op1( 0), Op2( 0), is32, + NULL, reset_unknown, c5_DFSR }, + { CRn( 5), CRm( 0), Op1( 0), Op2( 1), is32, + NULL, reset_unknown, c5_IFSR }, + { CRn( 5), CRm( 1), Op1( 0), Op2( 0), is32, + NULL, reset_unknown, c5_ADFSR }, + { CRn( 5), CRm( 1), Op1( 0), Op2( 1), is32, + NULL, reset_unknown, c5_AIFSR }, + + /* DFAR/IFAR: swapped by interrupt.S. */ + { CRn( 6), CRm( 0), Op1( 0), Op2( 0), is32, + NULL, reset_unknown, c6_DFAR }, + { CRn( 6), CRm( 0), Op1( 0), Op2( 2), is32, + NULL, reset_unknown, c6_IFAR }, + /* + * DC{C,I,CI}SW operations: + */ + { CRn( 7), CRm( 6), Op1( 0), Op2( 2), is32, access_dcsw}, + { CRn( 7), CRm(10), Op1( 0), Op2( 2), is32, access_dcsw}, + { CRn( 7), CRm(14), Op1( 0), Op2( 2), is32, access_dcsw}, + /* + * Dummy performance monitor implementation. + */ + { CRn( 9), CRm(12), Op1( 0), Op2( 0), is32, access_pmcr}, + { CRn( 9), CRm(12), Op1( 0), Op2( 1), is32, access_pmcntenset}, + { CRn( 9), CRm(12), Op1( 0), Op2( 2), is32, access_pmcntenclr}, + { CRn( 9), CRm(12), Op1( 0), Op2( 3), is32, access_pmovsr}, + { CRn( 9), CRm(12), Op1( 0), Op2( 5), is32, access_pmselr}, + { CRn( 9), CRm(12), Op1( 0), Op2( 6), is32, access_pmceid0}, + { CRn( 9), CRm(12), Op1( 0), Op2( 7), is32, access_pmceid1}, + { CRn( 9), CRm(13), Op1( 0), Op2( 0), is32, access_pmccntr}, + { CRn( 9), CRm(13), Op1( 0), Op2( 1), is32, access_pmxevtyper}, + { CRn( 9), CRm(13), Op1( 0), Op2( 2), is32, access_pmxevcntr}, + { CRn( 9), CRm(14), Op1( 0), Op2( 0), is32, access_pmuserenr}, + { CRn( 9), CRm(14), Op1( 0), Op2( 1), is32, access_pmintenset}, + { CRn( 9), CRm(14), Op1( 0), Op2( 2), is32, access_pmintenclr}, + + /* PRRR/NMRR (aka MAIR0/MAIR1): swapped by interrupt.S. */ + { CRn(10), CRm( 2), Op1( 0), Op2( 0), is32, + NULL, reset_unknown, c10_PRRR}, + { CRn(10), CRm( 2), Op1( 0), Op2( 1), is32, + NULL, reset_unknown, c10_NMRR}, + + /* VBAR: swapped by interrupt.S. */ + { CRn(12), CRm( 0), Op1( 0), Op2( 0), is32, + NULL, reset_val, c12_VBAR, 0x00000000 }, + + /* CONTEXTIDR/TPIDRURW/TPIDRURO/TPIDRPRW: swapped by interrupt.S. */ + { CRn(13), CRm( 0), Op1( 0), Op2( 1), is32, + NULL, reset_val, c13_CID, 0x00000000 }, + { CRn(13), CRm( 0), Op1( 0), Op2( 2), is32, + NULL, reset_unknown, c13_TID_URW }, + { CRn(13), CRm( 0), Op1( 0), Op2( 3), is32, + NULL, reset_unknown, c13_TID_URO }, + { CRn(13), CRm( 0), Op1( 0), Op2( 4), is32, + NULL, reset_unknown, c13_TID_PRIV }, +}; + +/* Target specific emulation tables */ +static struct kvm_coproc_target_table *target_tables[KVM_ARM_NUM_TARGETS]; + +void kvm_register_target_coproc_table(struct kvm_coproc_target_table *table) +{ + target_tables[table->target] = table; +} + +/* Get specific register table for this target. */ +static const struct coproc_reg *get_target_table(unsigned target, size_t *num) +{ + struct kvm_coproc_target_table *table; + + table = target_tables[target]; + *num = table->num; + return table->table; +} + +static const struct coproc_reg *find_reg(const struct coproc_params *params, + const struct coproc_reg table[], + unsigned int num) +{ + unsigned int i; + + for (i = 0; i < num; i++) { + const struct coproc_reg *r = &table[i]; + + if (params->is_64bit != r->is_64) + continue; + if (params->CRn != r->CRn) + continue; + if (params->CRm != r->CRm) + continue; + if (params->Op1 != r->Op1) + continue; + if (params->Op2 != r->Op2) + continue; + + return r; + } + return NULL; +} + +static int emulate_cp15(struct kvm_vcpu *vcpu, + const struct coproc_params *params) +{ + size_t num; + const struct coproc_reg *table, *r; + + trace_kvm_emulate_cp15_imp(params->Op1, params->Rt1, params->CRn, + params->CRm, params->Op2, params->is_write); + + table = get_target_table(vcpu->arch.target, &num); + + /* Search target-specific then generic table. */ + r = find_reg(params, table, num); + if (!r) + r = find_reg(params, cp15_regs, ARRAY_SIZE(cp15_regs)); + + if (likely(r)) { + /* If we don't have an accessor, we should never get here! */ + BUG_ON(!r->access); + + if (likely(r->access(vcpu, params, r))) { + /* Skip instruction, since it was emulated */ + kvm_skip_instr(vcpu, (vcpu->arch.hsr >> 25) & 1); + return 1; + } + /* If access function fails, it should complain. */ + } else { + kvm_err("Unsupported guest CP15 access at: %08x\n", + *vcpu_pc(vcpu)); + print_cp_instr(params); + } + kvm_inject_undefined(vcpu); + return 1; +} + +/** + * kvm_handle_cp15_64 -- handles a mrrc/mcrr trap on a guest CP15 access + * @vcpu: The VCPU pointer + * @run: The kvm_run struct + */ +int kvm_handle_cp15_64(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + struct coproc_params params; + + params.CRm = (vcpu->arch.hsr >> 1) & 0xf; + params.Rt1 = (vcpu->arch.hsr >> 5) & 0xf; + params.is_write = ((vcpu->arch.hsr & 1) == 0); + params.is_64bit = true; + + params.Op1 = (vcpu->arch.hsr >> 16) & 0xf; + params.Op2 = 0; + params.Rt2 = (vcpu->arch.hsr >> 10) & 0xf; + params.CRn = 0; + + return emulate_cp15(vcpu, ¶ms); +} + +static void reset_coproc_regs(struct kvm_vcpu *vcpu, + const struct coproc_reg *table, size_t num) +{ + unsigned long i; + + for (i = 0; i < num; i++) + if (table[i].reset) + table[i].reset(vcpu, &table[i]); +} + +/** + * kvm_handle_cp15_32 -- handles a mrc/mcr trap on a guest CP15 access + * @vcpu: The VCPU pointer + * @run: The kvm_run struct + */ +int kvm_handle_cp15_32(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + struct coproc_params params; + + params.CRm = (vcpu->arch.hsr >> 1) & 0xf; + params.Rt1 = (vcpu->arch.hsr >> 5) & 0xf; + params.is_write = ((vcpu->arch.hsr & 1) == 0); + params.is_64bit = false; + + params.CRn = (vcpu->arch.hsr >> 10) & 0xf; + params.Op1 = (vcpu->arch.hsr >> 14) & 0x7; + params.Op2 = (vcpu->arch.hsr >> 17) & 0x7; + params.Rt2 = 0; + + return emulate_cp15(vcpu, ¶ms); +} + +void kvm_coproc_table_init(void) +{ + unsigned int i; + + /* Make sure tables are unique and in order. */ + for (i = 1; i < ARRAY_SIZE(cp15_regs); i++) + BUG_ON(cmp_reg(&cp15_regs[i-1], &cp15_regs[i]) >= 0); +} + +/** + * kvm_reset_coprocs - sets cp15 registers to reset value + * @vcpu: The VCPU pointer + * + * This function finds the right table above and sets the registers on the + * virtual CPU struct to their architecturally defined reset values. + */ void kvm_reset_coprocs(struct kvm_vcpu *vcpu) { + size_t num; + const struct coproc_reg *table; + + /* Catch someone adding a register without putting in reset entry. */ + memset(vcpu->arch.cp15, 0x42, sizeof(vcpu->arch.cp15)); + + /* Generic chip reset first (so target could override). */ + reset_coproc_regs(vcpu, cp15_regs, ARRAY_SIZE(cp15_regs)); + + table = get_target_table(vcpu->arch.target, &num); + reset_coproc_regs(vcpu, table, num); + + for (num = 1; num < NR_CP15_REGS; num++) + if (vcpu->arch.cp15[num] == 0x42424242) + panic("Didn't reset vcpu->arch.cp15[%zi]", num); } |