KVM: PPC: Book3S HV: Add new POWER9 guest-accessible SPRs

This adds code to handle two new guest-accessible special-purpose
registers on POWER9: TIDR (thread ID register) and PSSCR (processor
stop status and control register).  They are context-switched
between host and guest, and the guest values can be read and set
via the one_reg interface.

The PSSCR contains some fields which are guest-accessible and some
which are only accessible in hypervisor mode.  We only allow the
guest-accessible fields to be read or set by userspace.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
This commit is contained in:
Paul Mackerras 2016-11-18 13:11:42 +11:00
parent 83677f551e
commit e9cf1e0856
6 changed files with 59 additions and 2 deletions

View File

@ -2023,6 +2023,8 @@ registers, find a list below:
PPC | KVM_REG_PPC_WORT | 64
PPC | KVM_REG_PPC_SPRG9 | 64
PPC | KVM_REG_PPC_DBSR | 32
PPC | KVM_REG_PPC_TIDR | 64
PPC | KVM_REG_PPC_PSSCR | 64
PPC | KVM_REG_PPC_TM_GPR0 | 64
...
PPC | KVM_REG_PPC_TM_GPR31 | 64

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@ -517,6 +517,8 @@ struct kvm_vcpu_arch {
ulong tcscr;
ulong acop;
ulong wort;
ulong tid;
ulong psscr;
ulong shadow_srr1;
#endif
u32 vrsave; /* also USPRG0 */

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@ -573,6 +573,10 @@ struct kvm_get_htab_header {
#define KVM_REG_PPC_SPRG9 (KVM_REG_PPC | KVM_REG_SIZE_U64 | 0xba)
#define KVM_REG_PPC_DBSR (KVM_REG_PPC | KVM_REG_SIZE_U32 | 0xbb)
/* POWER9 registers */
#define KVM_REG_PPC_TIDR (KVM_REG_PPC | KVM_REG_SIZE_U64 | 0xbc)
#define KVM_REG_PPC_PSSCR (KVM_REG_PPC | KVM_REG_SIZE_U64 | 0xbd)
/* Transactional Memory checkpointed state:
* This is all GPRs, all VSX regs and a subset of SPRs
*/

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@ -548,6 +548,8 @@ int main(void)
DEFINE(VCPU_TCSCR, offsetof(struct kvm_vcpu, arch.tcscr));
DEFINE(VCPU_ACOP, offsetof(struct kvm_vcpu, arch.acop));
DEFINE(VCPU_WORT, offsetof(struct kvm_vcpu, arch.wort));
DEFINE(VCPU_TID, offsetof(struct kvm_vcpu, arch.tid));
DEFINE(VCPU_PSSCR, offsetof(struct kvm_vcpu, arch.psscr));
DEFINE(VCORE_ENTRY_EXIT, offsetof(struct kvmppc_vcore, entry_exit_map));
DEFINE(VCORE_IN_GUEST, offsetof(struct kvmppc_vcore, in_guest));
DEFINE(VCORE_NAPPING_THREADS, offsetof(struct kvmppc_vcore, napping_threads));

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@ -1230,6 +1230,12 @@ static int kvmppc_get_one_reg_hv(struct kvm_vcpu *vcpu, u64 id,
case KVM_REG_PPC_WORT:
*val = get_reg_val(id, vcpu->arch.wort);
break;
case KVM_REG_PPC_TIDR:
*val = get_reg_val(id, vcpu->arch.tid);
break;
case KVM_REG_PPC_PSSCR:
*val = get_reg_val(id, vcpu->arch.psscr);
break;
case KVM_REG_PPC_VPA_ADDR:
spin_lock(&vcpu->arch.vpa_update_lock);
*val = get_reg_val(id, vcpu->arch.vpa.next_gpa);
@ -1431,6 +1437,12 @@ static int kvmppc_set_one_reg_hv(struct kvm_vcpu *vcpu, u64 id,
case KVM_REG_PPC_WORT:
vcpu->arch.wort = set_reg_val(id, *val);
break;
case KVM_REG_PPC_TIDR:
vcpu->arch.tid = set_reg_val(id, *val);
break;
case KVM_REG_PPC_PSSCR:
vcpu->arch.psscr = set_reg_val(id, *val) & PSSCR_GUEST_VIS;
break;
case KVM_REG_PPC_VPA_ADDR:
addr = set_reg_val(id, *val);
r = -EINVAL;

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@ -523,6 +523,10 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
* *
*****************************************************************************/
/* Stack frame offsets */
#define STACK_SLOT_TID (112-16)
#define STACK_SLOT_PSSCR (112-24)
.global kvmppc_hv_entry
kvmppc_hv_entry:
@ -700,6 +704,14 @@ kvmppc_got_guest:
mtspr SPRN_PURR,r7
mtspr SPRN_SPURR,r8
/* Save host values of some registers */
BEGIN_FTR_SECTION
mfspr r5, SPRN_TIDR
mfspr r6, SPRN_PSSCR
std r5, STACK_SLOT_TID(r1)
std r6, STACK_SLOT_PSSCR(r1)
END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
BEGIN_FTR_SECTION
/* Set partition DABR */
/* Do this before re-enabling PMU to avoid P7 DABR corruption bug */
@ -824,6 +836,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
mtspr SPRN_PID, r7
mtspr SPRN_WORT, r8
BEGIN_FTR_SECTION
/* POWER8-only registers */
ld r5, VCPU_TCSCR(r4)
ld r6, VCPU_ACOP(r4)
ld r7, VCPU_CSIGR(r4)
@ -832,7 +845,14 @@ BEGIN_FTR_SECTION
mtspr SPRN_ACOP, r6
mtspr SPRN_CSIGR, r7
mtspr SPRN_TACR, r8
END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
FTR_SECTION_ELSE
/* POWER9-only registers */
ld r5, VCPU_TID(r4)
ld r6, VCPU_PSSCR(r4)
oris r6, r6, PSSCR_EC@h /* This makes stop trap to HV */
mtspr SPRN_TIDR, r5
mtspr SPRN_PSSCR, r6
ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300)
8:
/*
@ -1362,7 +1382,14 @@ BEGIN_FTR_SECTION
std r6, VCPU_ACOP(r9)
std r7, VCPU_CSIGR(r9)
std r8, VCPU_TACR(r9)
END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
FTR_SECTION_ELSE
mfspr r5, SPRN_TIDR
mfspr r6, SPRN_PSSCR
std r5, VCPU_TID(r9)
rldicl r6, r6, 4, 50 /* r6 &= PSSCR_GUEST_VIS */
rotldi r6, r6, 60
std r6, VCPU_PSSCR(r9)
ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300)
/*
* Restore various registers to 0, where non-zero values
* set by the guest could disrupt the host.
@ -1531,6 +1558,14 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
slbia
ptesync
/* Restore host values of some registers */
BEGIN_FTR_SECTION
ld r5, STACK_SLOT_TID(r1)
ld r6, STACK_SLOT_PSSCR(r1)
mtspr SPRN_TIDR, r5
mtspr SPRN_PSSCR, r6
END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
/*
* POWER7/POWER8 guest -> host partition switch code.
* We don't have to lock against tlbies but we do