[PATCH v3 04/11] KVM: arm: common infrastructure for handling AArch32 CP14/CP15
Christoffer Dall
christoffer.dall at linaro.org
Mon Jun 29 12:43:34 PDT 2015
On Mon, Jun 22, 2015 at 06:41:27PM +0800, Zhichao Huang wrote:
> As we're about to trap a bunch of CP14 registers, let's rework
> the CP15 handling so it can be generalized and work with multiple
> tables.
>
> Signed-off-by: Zhichao Huang <zhichao.huang at linaro.org>
> ---
> arch/arm/kvm/coproc.c | 176 ++++++++++++++++++++++++++---------------
> arch/arm/kvm/interrupts_head.S | 2 +-
> 2 files changed, 112 insertions(+), 66 deletions(-)
>
> diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c
> index 9d283d9..d23395b 100644
> --- a/arch/arm/kvm/coproc.c
> +++ b/arch/arm/kvm/coproc.c
> @@ -375,6 +375,9 @@ static const struct coproc_reg cp15_regs[] = {
> { CRn(15), CRm( 0), Op1( 4), Op2( 0), is32, access_cbar},
> };
>
> +static const struct coproc_reg cp14_regs[] = {
> +};
> +
> /* Target specific emulation tables */
> static struct kvm_coproc_target_table *target_tables[KVM_ARM_NUM_TARGETS];
>
> @@ -424,47 +427,75 @@ static const struct coproc_reg *find_reg(const struct coproc_params *params,
> return NULL;
> }
>
> -static int emulate_cp15(struct kvm_vcpu *vcpu,
> - const struct coproc_params *params)
> +/*
> + * emulate_cp -- tries to match a cp14/cp15 access in a handling table,
> + * and call the corresponding trap handler.
> + *
> + * @params: pointer to the descriptor of the access
> + * @table: array of trap descriptors
> + * @num: size of the trap descriptor array
> + *
> + * Return 0 if the access has been handled, and -1 if not.
> + */
> +static int emulate_cp(struct kvm_vcpu *vcpu,
> + const struct coproc_params *params,
> + const struct coproc_reg *table,
> + size_t num)
> {
> - 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);
> + const struct coproc_reg *r;
>
> - table = get_target_table(vcpu->arch.target, &num);
> + if (!table)
> + return -1; /* Not handled */
>
> - /* 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 (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, kvm_vcpu_trap_il_is32bit(vcpu));
> - return 1;
> }
> - /* If access function fails, it should complain. */
> - } else {
> - kvm_err("Unsupported guest CP15 access at: %08lx\n",
> - *vcpu_pc(vcpu));
> - print_cp_instr(params);
> +
> + /* Handled */
> + return 0;
> }
> +
> + /* Not handled */
> + return -1;
> +}
> +
> +static void unhandled_cp_access(struct kvm_vcpu *vcpu,
> + const struct coproc_params *params)
> +{
> + u8 hsr_ec = kvm_vcpu_trap_get_class(vcpu);
> + int cp;
> +
> + switch (hsr_ec) {
> + case HSR_EC_CP15_32:
> + case HSR_EC_CP15_64:
> + cp = 15;
> + break;
> + case HSR_EC_CP14_MR:
> + case HSR_EC_CP14_64:
> + cp = 14;
> + break;
> + default:
> + WARN_ON((cp = -1));
> + }
> +
> + kvm_err("Unsupported guest CP%d access at: %08lx\n",
> + cp, *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)
> +int kvm_handle_cp_64(struct kvm_vcpu *vcpu,
> + const struct coproc_reg *global,
> + size_t nr_global,
> + const struct coproc_reg *target_specific,
> + size_t nr_specific)
> {
> struct coproc_params params;
>
> @@ -478,7 +509,13 @@ int kvm_handle_cp15_64(struct kvm_vcpu *vcpu, struct kvm_run *run)
> params.Rt2 = (kvm_vcpu_get_hsr(vcpu) >> 10) & 0xf;
> params.CRm = 0;
>
> - return emulate_cp15(vcpu, ¶ms);
> + if (!emulate_cp(vcpu, ¶ms, target_specific, nr_specific))
> + return 1;
> + if (!emulate_cp(vcpu, ¶ms, global, nr_global))
> + return 1;
> +
> + unhandled_cp_access(vcpu, ¶ms);
> + return 1;
> }
>
> static void reset_coproc_regs(struct kvm_vcpu *vcpu,
> @@ -491,12 +528,11 @@ static void reset_coproc_regs(struct kvm_vcpu *vcpu,
> 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)
> +int kvm_handle_cp_32(struct kvm_vcpu *vcpu,
> + const struct coproc_reg *global,
> + size_t nr_global,
> + const struct coproc_reg *target_specific,
> + size_t nr_specific)
> {
> struct coproc_params params;
>
> @@ -510,33 +546,57 @@ int kvm_handle_cp15_32(struct kvm_vcpu *vcpu, struct kvm_run *run)
> params.Op2 = (kvm_vcpu_get_hsr(vcpu) >> 17) & 0x7;
> params.Rt2 = 0;
>
> - return emulate_cp15(vcpu, ¶ms);
> + if (!emulate_cp(vcpu, ¶ms, target_specific, nr_specific))
> + return 1;
> + if (!emulate_cp(vcpu, ¶ms, global, nr_global))
> + return 1;
> +
> + unhandled_cp_access(vcpu, ¶ms);
> + return 1;
> }
>
> /**
> - * kvm_handle_cp14_64 -- handles a mrrc/mcrr trap on a guest CP14 access
> + * 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_cp14_64(struct kvm_vcpu *vcpu, struct kvm_run *run)
> +int kvm_handle_cp15_64(struct kvm_vcpu *vcpu, struct kvm_run *run)
> {
> - struct coproc_params params;
> + const struct coproc_reg *target_specific;
> + size_t num;
>
> - params.CRn = (kvm_vcpu_get_hsr(vcpu) >> 1) & 0xf;
> - params.Rt1 = (kvm_vcpu_get_hsr(vcpu) >> 5) & 0xf;
> - params.is_write = ((kvm_vcpu_get_hsr(vcpu) & 1) == 0);
> - params.is_64bit = true;
> + target_specific = get_target_table(vcpu->arch.target, &num);
> + return kvm_handle_cp_64(vcpu,
> + cp15_regs, ARRAY_SIZE(cp15_regs),
> + target_specific, num);
> +}
>
> - params.Op1 = (kvm_vcpu_get_hsr(vcpu) >> 16) & 0xf;
> - params.Op2 = 0;
> - params.Rt2 = (kvm_vcpu_get_hsr(vcpu) >> 10) & 0xf;
> - params.CRm = 0;
> +/**
> + * 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)
> +{
> + const struct coproc_reg *target_specific;
> + size_t num;
>
> - (void)trap_raz_wi(vcpu, ¶ms, NULL);
> + target_specific = get_target_table(vcpu->arch.target, &num);
> + return kvm_handle_cp_32(vcpu,
> + cp15_regs, ARRAY_SIZE(cp15_regs),
> + target_specific, num);
> +}
>
> - /* handled */
> - kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
> - return 1;
> +/**
> + * kvm_handle_cp14_64 -- handles a mrrc/mcrr trap on a guest CP14 access
> + * @vcpu: The VCPU pointer
> + * @run: The kvm_run struct
> + */
> +int kvm_handle_cp14_64(struct kvm_vcpu *vcpu, struct kvm_run *run)
> +{
> + return kvm_handle_cp_64(vcpu,
> + cp14_regs, ARRAY_SIZE(cp14_regs),
> + NULL, 0);
> }
>
> /**
> @@ -546,23 +606,9 @@ int kvm_handle_cp14_64(struct kvm_vcpu *vcpu, struct kvm_run *run)
> */
> int kvm_handle_cp14_32(struct kvm_vcpu *vcpu, struct kvm_run *run)
> {
> - struct coproc_params params;
> -
> - params.CRm = (kvm_vcpu_get_hsr(vcpu) >> 1) & 0xf;
> - params.Rt1 = (kvm_vcpu_get_hsr(vcpu) >> 5) & 0xf;
> - params.is_write = ((kvm_vcpu_get_hsr(vcpu) & 1) == 0);
> - params.is_64bit = false;
> -
> - params.CRn = (kvm_vcpu_get_hsr(vcpu) >> 10) & 0xf;
> - params.Op1 = (kvm_vcpu_get_hsr(vcpu) >> 14) & 0x7;
> - params.Op2 = (kvm_vcpu_get_hsr(vcpu) >> 17) & 0x7;
> - params.Rt2 = 0;
> -
> - (void)trap_raz_wi(vcpu, ¶ms, NULL);
> -
> - /* handled */
> - kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
> - return 1;
> + return kvm_handle_cp_32(vcpu,
> + cp14_regs, ARRAY_SIZE(cp14_regs),
> + NULL, 0);
> }
>
> /******************************************************************************
> diff --git a/arch/arm/kvm/interrupts_head.S b/arch/arm/kvm/interrupts_head.S
> index f85c447..a20b9ad 100644
> --- a/arch/arm/kvm/interrupts_head.S
> +++ b/arch/arm/kvm/interrupts_head.S
> @@ -618,7 +618,7 @@ ARM_BE8(rev r6, r6 )
> * (hardware reset value is 0) */
> .macro set_hdcr operation
> mrc p15, 4, r2, c1, c1, 1
> - ldr r3, =(HDCR_TPM|HDCR_TPMCR|HDCR_TDRA|HDCR_TDOSA|HDCR_TDA)
> + ldr r3, =(HDCR_TPM|HDCR_TPMCR)
why do we stop trapping accesses here?
-Christoffer
> .if \operation == vmentry
> orr r2, r2, r3 @ Trap some perfmon accesses
> .else
> --
> 1.7.12.4
>
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