From ab86bd600400357ffa0dfdb1797f587476d01352 Mon Sep 17 00:00:00 2001 From: James Hogan Date: Tue, 2 Dec 2014 15:48:24 +0000 Subject: MIPS: KVM: Expose MSA registers Add KVM register numbers for the MIPS SIMD Architecture (MSA) registers, and implement access to them with the KVM_GET_ONE_REG / KVM_SET_ONE_REG ioctls when the MSA capability is enabled (exposed in a later patch) and present in the guest according to its Config3.MSAP bit. The MSA vector registers use the same register numbers as the FPU registers except with a different size (128bits). Since MSA depends on Status.FR=1, these registers are inaccessible when Status.FR=0. These registers are returned as a single native endian 128bit value, rather than least significant half first with each 64-bit half native endian as the kernel uses internally. Signed-off-by: James Hogan Cc: Paolo Bonzini Cc: Paul Burton Cc: Ralf Baechle Cc: Gleb Natapov Cc: Jonathan Corbet Cc: linux-mips@linux-mips.org Cc: kvm@vger.kernel.org Cc: linux-api@vger.kernel.org Cc: linux-doc@vger.kernel.org --- arch/mips/include/uapi/asm/kvm.h | 12 ++++++-- arch/mips/kvm/mips.c | 65 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 75 insertions(+), 2 deletions(-) (limited to 'arch/mips') diff --git a/arch/mips/include/uapi/asm/kvm.h b/arch/mips/include/uapi/asm/kvm.h index 401e6a6..6985eb5 100644 --- a/arch/mips/include/uapi/asm/kvm.h +++ b/arch/mips/include/uapi/asm/kvm.h @@ -58,7 +58,7 @@ struct kvm_fpu { * * Register set = 2: KVM specific registers (see definitions below). * - * Register set = 3: FPU registers (see definitions below). + * Register set = 3: FPU / MSA registers (see definitions below). * * Other sets registers may be added in the future. Each set would * have its own identifier in bits[31..16]. @@ -148,7 +148,7 @@ struct kvm_fpu { /* - * KVM_REG_MIPS_FPU - Floating Point registers. + * KVM_REG_MIPS_FPU - Floating Point and MIPS SIMD Architecture (MSA) registers. * * bits[15..8] - Register subset (see definitions below). * bits[7..5] - Must be zero. @@ -157,12 +157,14 @@ struct kvm_fpu { #define KVM_REG_MIPS_FPR (KVM_REG_MIPS_FPU | 0x0000000000000000ULL) #define KVM_REG_MIPS_FCR (KVM_REG_MIPS_FPU | 0x0000000000000100ULL) +#define KVM_REG_MIPS_MSACR (KVM_REG_MIPS_FPU | 0x0000000000000200ULL) /* * KVM_REG_MIPS_FPR - Floating point / Vector registers. */ #define KVM_REG_MIPS_FPR_32(n) (KVM_REG_MIPS_FPR | KVM_REG_SIZE_U32 | (n)) #define KVM_REG_MIPS_FPR_64(n) (KVM_REG_MIPS_FPR | KVM_REG_SIZE_U64 | (n)) +#define KVM_REG_MIPS_VEC_128(n) (KVM_REG_MIPS_FPR | KVM_REG_SIZE_U128 | (n)) /* * KVM_REG_MIPS_FCR - Floating point control registers. @@ -170,6 +172,12 @@ struct kvm_fpu { #define KVM_REG_MIPS_FCR_IR (KVM_REG_MIPS_FCR | KVM_REG_SIZE_U32 | 0) #define KVM_REG_MIPS_FCR_CSR (KVM_REG_MIPS_FCR | KVM_REG_SIZE_U32 | 31) +/* + * KVM_REG_MIPS_MSACR - MIPS SIMD Architecture (MSA) control registers. + */ +#define KVM_REG_MIPS_MSA_IR (KVM_REG_MIPS_MSACR | KVM_REG_SIZE_U32 | 0) +#define KVM_REG_MIPS_MSA_CSR (KVM_REG_MIPS_MSACR | KVM_REG_SIZE_U32 | 1) + /* * KVM MIPS specific structures and definitions diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c index e02c7e5..35d3146 100644 --- a/arch/mips/kvm/mips.c +++ b/arch/mips/kvm/mips.c @@ -531,6 +531,7 @@ static int kvm_mips_get_reg(struct kvm_vcpu *vcpu, struct mips_fpu_struct *fpu = &vcpu->arch.fpu; int ret; s64 v; + s64 vs[2]; unsigned int idx; switch (reg->id) { @@ -579,6 +580,35 @@ static int kvm_mips_get_reg(struct kvm_vcpu *vcpu, v = fpu->fcr31; break; + /* MIPS SIMD Architecture (MSA) registers */ + case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31): + if (!kvm_mips_guest_has_msa(&vcpu->arch)) + return -EINVAL; + /* Can't access MSA registers in FR=0 mode */ + if (!(kvm_read_c0_guest_status(cop0) & ST0_FR)) + return -EINVAL; + idx = reg->id - KVM_REG_MIPS_VEC_128(0); +#ifdef CONFIG_CPU_LITTLE_ENDIAN + /* least significant byte first */ + vs[0] = get_fpr64(&fpu->fpr[idx], 0); + vs[1] = get_fpr64(&fpu->fpr[idx], 1); +#else + /* most significant byte first */ + vs[0] = get_fpr64(&fpu->fpr[idx], 1); + vs[1] = get_fpr64(&fpu->fpr[idx], 0); +#endif + break; + case KVM_REG_MIPS_MSA_IR: + if (!kvm_mips_guest_has_msa(&vcpu->arch)) + return -EINVAL; + v = boot_cpu_data.msa_id; + break; + case KVM_REG_MIPS_MSA_CSR: + if (!kvm_mips_guest_has_msa(&vcpu->arch)) + return -EINVAL; + v = fpu->msacsr; + break; + /* Co-processor 0 registers */ case KVM_REG_MIPS_CP0_INDEX: v = (long)kvm_read_c0_guest_index(cop0); @@ -664,6 +694,10 @@ static int kvm_mips_get_reg(struct kvm_vcpu *vcpu, u32 v32 = (u32)v; return put_user(v32, uaddr32); + } else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) { + void __user *uaddr = (void __user *)(long)reg->addr; + + return copy_to_user(uaddr, vs, 16); } else { return -EINVAL; } @@ -675,6 +709,7 @@ static int kvm_mips_set_reg(struct kvm_vcpu *vcpu, struct mips_coproc *cop0 = vcpu->arch.cop0; struct mips_fpu_struct *fpu = &vcpu->arch.fpu; s64 v; + s64 vs[2]; unsigned int idx; if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) { @@ -689,6 +724,10 @@ static int kvm_mips_set_reg(struct kvm_vcpu *vcpu, if (get_user(v32, uaddr32) != 0) return -EFAULT; v = (s64)v32; + } else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) { + void __user *uaddr = (void __user *)(long)reg->addr; + + return copy_from_user(vs, uaddr, 16); } else { return -EINVAL; } @@ -742,6 +781,32 @@ static int kvm_mips_set_reg(struct kvm_vcpu *vcpu, fpu->fcr31 = v; break; + /* MIPS SIMD Architecture (MSA) registers */ + case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31): + if (!kvm_mips_guest_has_msa(&vcpu->arch)) + return -EINVAL; + idx = reg->id - KVM_REG_MIPS_VEC_128(0); +#ifdef CONFIG_CPU_LITTLE_ENDIAN + /* least significant byte first */ + set_fpr64(&fpu->fpr[idx], 0, vs[0]); + set_fpr64(&fpu->fpr[idx], 1, vs[1]); +#else + /* most significant byte first */ + set_fpr64(&fpu->fpr[idx], 1, vs[0]); + set_fpr64(&fpu->fpr[idx], 0, vs[1]); +#endif + break; + case KVM_REG_MIPS_MSA_IR: + if (!kvm_mips_guest_has_msa(&vcpu->arch)) + return -EINVAL; + /* Read-only */ + break; + case KVM_REG_MIPS_MSA_CSR: + if (!kvm_mips_guest_has_msa(&vcpu->arch)) + return -EINVAL; + fpu->msacsr = v; + break; + /* Co-processor 0 registers */ case KVM_REG_MIPS_CP0_INDEX: kvm_write_c0_guest_index(cop0, v); -- cgit v1.1