diff options
| -rw-r--r-- | arch/powerpc/kvm/Makefile | 5 | ||||
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv_rm_xics.c | 406 | ||||
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv_rmhandlers.S | 18 | ||||
| -rw-r--r-- | arch/powerpc/kvm/book3s_xics.c | 64 | ||||
| -rw-r--r-- | arch/powerpc/kvm/book3s_xics.h | 16 |
5 files changed, 490 insertions, 19 deletions
diff --git a/arch/powerpc/kvm/Makefile b/arch/powerpc/kvm/Makefile index f9b87b540450..422de3f4d46c 100644 --- a/arch/powerpc/kvm/Makefile +++ b/arch/powerpc/kvm/Makefile @@ -72,12 +72,15 @@ kvm-book3s_64-objs-$(CONFIG_KVM_BOOK3S_64_HV) := \ book3s_hv.o \ book3s_hv_interrupts.o \ book3s_64_mmu_hv.o +kvm-book3s_64-builtin-xics-objs-$(CONFIG_KVM_XICS) := \ + book3s_hv_rm_xics.o kvm-book3s_64-builtin-objs-$(CONFIG_KVM_BOOK3S_64_HV) := \ book3s_hv_rmhandlers.o \ book3s_hv_rm_mmu.o \ book3s_64_vio_hv.o \ book3s_hv_ras.o \ - book3s_hv_builtin.o + book3s_hv_builtin.o \ + $(kvm-book3s_64-builtin-xics-objs-y) kvm-book3s_64-objs-$(CONFIG_KVM_XICS) += \ book3s_xics.o diff --git a/arch/powerpc/kvm/book3s_hv_rm_xics.c b/arch/powerpc/kvm/book3s_hv_rm_xics.c new file mode 100644 index 000000000000..b4b0082f761c --- /dev/null +++ b/arch/powerpc/kvm/book3s_hv_rm_xics.c @@ -0,0 +1,406 @@ +/* + * Copyright 2012 Michael Ellerman, IBM Corporation. + * Copyright 2012 Benjamin Herrenschmidt, IBM Corporation + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License, version 2, as + * published by the Free Software Foundation. + */ + +#include <linux/kernel.h> +#include <linux/kvm_host.h> +#include <linux/err.h> + +#include <asm/kvm_book3s.h> +#include <asm/kvm_ppc.h> +#include <asm/hvcall.h> +#include <asm/xics.h> +#include <asm/debug.h> +#include <asm/synch.h> +#include <asm/ppc-opcode.h> + +#include "book3s_xics.h" + +#define DEBUG_PASSUP + +static inline void rm_writeb(unsigned long paddr, u8 val) +{ + __asm__ __volatile__("sync; stbcix %0,0,%1" + : : "r" (val), "r" (paddr) : "memory"); +} + +static void icp_rm_set_vcpu_irq(struct kvm_vcpu *vcpu, + struct kvm_vcpu *this_vcpu) +{ + struct kvmppc_icp *this_icp = this_vcpu->arch.icp; + unsigned long xics_phys; + int cpu; + + /* Mark the target VCPU as having an interrupt pending */ + vcpu->stat.queue_intr++; + set_bit(BOOK3S_IRQPRIO_EXTERNAL_LEVEL, &vcpu->arch.pending_exceptions); + + /* Kick self ? Just set MER and return */ + if (vcpu == this_vcpu) { + mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) | LPCR_MER); + return; + } + + /* Check if the core is loaded, if not, too hard */ + cpu = vcpu->cpu; + if (cpu < 0 || cpu >= nr_cpu_ids) { + this_icp->rm_action |= XICS_RM_KICK_VCPU; + this_icp->rm_kick_target = vcpu; + return; + } + /* In SMT cpu will always point to thread 0, we adjust it */ + cpu += vcpu->arch.ptid; + + /* Not too hard, then poke the target */ + xics_phys = paca[cpu].kvm_hstate.xics_phys; + rm_writeb(xics_phys + XICS_MFRR, IPI_PRIORITY); +} + +static void icp_rm_clr_vcpu_irq(struct kvm_vcpu *vcpu) +{ + /* Note: Only called on self ! */ + clear_bit(BOOK3S_IRQPRIO_EXTERNAL_LEVEL, + &vcpu->arch.pending_exceptions); + mtspr(SPRN_LPCR, mfspr(SPRN_LPCR) & ~LPCR_MER); +} + +static inline bool icp_rm_try_update(struct kvmppc_icp *icp, + union kvmppc_icp_state old, + union kvmppc_icp_state new) +{ + struct kvm_vcpu *this_vcpu = local_paca->kvm_hstate.kvm_vcpu; + bool success; + + /* Calculate new output value */ + new.out_ee = (new.xisr && (new.pending_pri < new.cppr)); + + /* Attempt atomic update */ + success = cmpxchg64(&icp->state.raw, old.raw, new.raw) == old.raw; + if (!success) + goto bail; + + /* + * Check for output state update + * + * Note that this is racy since another processor could be updating + * the state already. This is why we never clear the interrupt output + * here, we only ever set it. The clear only happens prior to doing + * an update and only by the processor itself. Currently we do it + * in Accept (H_XIRR) and Up_Cppr (H_XPPR). + * + * We also do not try to figure out whether the EE state has changed, + * we unconditionally set it if the new state calls for it. The reason + * for that is that we opportunistically remove the pending interrupt + * flag when raising CPPR, so we need to set it back here if an + * interrupt is still pending. + */ + if (new.out_ee) + icp_rm_set_vcpu_irq(icp->vcpu, this_vcpu); + + /* Expose the state change for debug purposes */ + this_vcpu->arch.icp->rm_dbgstate = new; + this_vcpu->arch.icp->rm_dbgtgt = icp->vcpu; + + bail: + return success; +} + +static inline int check_too_hard(struct kvmppc_xics *xics, + struct kvmppc_icp *icp) +{ + return (xics->real_mode_dbg || icp->rm_action) ? H_TOO_HARD : H_SUCCESS; +} + +static void icp_rm_down_cppr(struct kvmppc_xics *xics, struct kvmppc_icp *icp, + u8 new_cppr) +{ + union kvmppc_icp_state old_state, new_state; + bool resend; + + /* + * This handles several related states in one operation: + * + * ICP State: Down_CPPR + * + * Load CPPR with new value and if the XISR is 0 + * then check for resends: + * + * ICP State: Resend + * + * If MFRR is more favored than CPPR, check for IPIs + * and notify ICS of a potential resend. This is done + * asynchronously (when used in real mode, we will have + * to exit here). + * + * We do not handle the complete Check_IPI as documented + * here. In the PAPR, this state will be used for both + * Set_MFRR and Down_CPPR. However, we know that we aren't + * changing the MFRR state here so we don't need to handle + * the case of an MFRR causing a reject of a pending irq, + * this will have been handled when the MFRR was set in the + * first place. + * + * Thus we don't have to handle rejects, only resends. + * + * When implementing real mode for HV KVM, resend will lead to + * a H_TOO_HARD return and the whole transaction will be handled + * in virtual mode. + */ + do { + old_state = new_state = ACCESS_ONCE(icp->state); + + /* Down_CPPR */ + new_state.cppr = new_cppr; + + /* + * Cut down Resend / Check_IPI / IPI + * + * The logic is that we cannot have a pending interrupt + * trumped by an IPI at this point (see above), so we + * know that either the pending interrupt is already an + * IPI (in which case we don't care to override it) or + * it's either more favored than us or non existent + */ + if (new_state.mfrr < new_cppr && + new_state.mfrr <= new_state.pending_pri) { + new_state.pending_pri = new_state.mfrr; + new_state.xisr = XICS_IPI; + } + + /* Latch/clear resend bit */ + resend = new_state.need_resend; + new_state.need_resend = 0; + + } while (!icp_rm_try_update(icp, old_state, new_state)); + + /* + * Now handle resend checks. Those are asynchronous to the ICP + * state update in HW (ie bus transactions) so we can handle them + * separately here as well. + */ + if (resend) + icp->rm_action |= XICS_RM_CHECK_RESEND; +} + + +unsigned long kvmppc_rm_h_xirr(struct kvm_vcpu *vcpu) +{ + union kvmppc_icp_state old_state, new_state; + struct kvmppc_xics *xics = vcpu->kvm->arch.xics; + struct kvmppc_icp *icp = vcpu->arch.icp; + u32 xirr; + + if (!xics || !xics->real_mode) + return H_TOO_HARD; + + /* First clear the interrupt */ + icp_rm_clr_vcpu_irq(icp->vcpu); + + /* + * ICP State: Accept_Interrupt + * + * Return the pending interrupt (if any) along with the + * current CPPR, then clear the XISR & set CPPR to the + * pending priority + */ + do { + old_state = new_state = ACCESS_ONCE(icp->state); + + xirr = old_state.xisr | (((u32)old_state.cppr) << 24); + if (!old_state.xisr) + break; + new_state.cppr = new_state.pending_pri; + new_state.pending_pri = 0xff; + new_state.xisr = 0; + + } while (!icp_rm_try_update(icp, old_state, new_state)); + + /* Return the result in GPR4 */ + vcpu->arch.gpr[4] = xirr; + + return check_too_hard(xics, icp); +} + +int kvmppc_rm_h_ipi(struct kvm_vcpu *vcpu, unsigned long server, + unsigned long mfrr) +{ + union kvmppc_icp_state old_state, new_state; + struct kvmppc_xics *xics = vcpu->kvm->arch.xics; + struct kvmppc_icp *icp, *this_icp = vcpu->arch.icp; + u32 reject; + bool resend; + bool local; + + if (!xics || !xics->real_mode) + return H_TOO_HARD; + + local = this_icp->server_num == server; + if (local) + icp = this_icp; + else + icp = kvmppc_xics_find_server(vcpu->kvm, server); + if (!icp) + return H_PARAMETER; + + /* + * ICP state: Set_MFRR + * + * If the CPPR is more favored than the new MFRR, then + * nothing needs to be done as there can be no XISR to + * reject. + * + * If the CPPR is less favored, then we might be replacing + * an interrupt, and thus need to possibly reject it as in + * + * ICP state: Check_IPI + */ + do { + old_state = new_state = ACCESS_ONCE(icp->state); + + /* Set_MFRR */ + new_state.mfrr = mfrr; + + /* Check_IPI */ + reject = 0; + resend = false; + if (mfrr < new_state.cppr) { + /* Reject a pending interrupt if not an IPI */ + if (mfrr <= new_state.pending_pri) + reject = new_state.xisr; + new_state.pending_pri = mfrr; + new_state.xisr = XICS_IPI; + } + + if (mfrr > old_state.mfrr && mfrr > new_state.cppr) { + resend = new_state.need_resend; + new_state.need_resend = 0; + } + } while (!icp_rm_try_update(icp, old_state, new_state)); + + /* Pass rejects to virtual mode */ + if (reject && reject != XICS_IPI) { + this_icp->rm_action |= XICS_RM_REJECT; + this_icp->rm_reject = reject; + } + + /* Pass resends to virtual mode */ + if (resend) + this_icp->rm_action |= XICS_RM_CHECK_RESEND; + + return check_too_hard(xics, this_icp); +} + +int kvmppc_rm_h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr) +{ + union kvmppc_icp_state old_state, new_state; + struct kvmppc_xics *xics = vcpu->kvm->arch.xics; + struct kvmppc_icp *icp = vcpu->arch.icp; + u32 reject; + + if (!xics || !xics->real_mode) + return H_TOO_HARD; + + /* + * ICP State: Set_CPPR + * + * We can safely compare the new value with the current + * value outside of the transaction as the CPPR is only + * ever changed by the processor on itself + */ + if (cppr > icp->state.cppr) { + icp_rm_down_cppr(xics, icp, cppr); + goto bail; + } else if (cppr == icp->state.cppr) + return H_SUCCESS; + + /* + * ICP State: Up_CPPR + * + * The processor is raising its priority, this can result + * in a rejection of a pending interrupt: + * + * ICP State: Reject_Current + * + * We can remove EE from the current processor, the update + * transaction will set it again if needed + */ + icp_rm_clr_vcpu_irq(icp->vcpu); + + do { + old_state = new_state = ACCESS_ONCE(icp->state); + + reject = 0; + new_state.cppr = cppr; + + if (cppr <= new_state.pending_pri) { + reject = new_state.xisr; + new_state.xisr = 0; + new_state.pending_pri = 0xff; + } + + } while (!icp_rm_try_update(icp, old_state, new_state)); + + /* Pass rejects to virtual mode */ + if (reject && reject != XICS_IPI) { + icp->rm_action |= XICS_RM_REJECT; + icp->rm_reject = reject; + } + bail: + return check_too_hard(xics, icp); +} + +int kvmppc_rm_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr) +{ + struct kvmppc_xics *xics = vcpu->kvm->arch.xics; + struct kvmppc_icp *icp = vcpu->arch.icp; + struct kvmppc_ics *ics; + struct ics_irq_state *state; + u32 irq = xirr & 0x00ffffff; + u16 src; + + if (!xics || !xics->real_mode) + return H_TOO_HARD; + + /* + * ICP State: EOI + * + * Note: If EOI is incorrectly used by SW to lower the CPPR + * value (ie more favored), we do not check for rejection of + * a pending interrupt, this is a SW error and PAPR sepcifies + * that we don't have to deal with it. + * + * The sending of an EOI to the ICS is handled after the + * CPPR update + * + * ICP State: Down_CPPR which we handle + * in a separate function as it's shared with H_CPPR. + */ + icp_rm_down_cppr(xics, icp, xirr >> 24); + + /* IPIs have no EOI */ + if (irq == XICS_IPI) + goto bail; + /* + * EOI handling: If the interrupt is still asserted, we need to + * resend it. We can take a lockless "peek" at the ICS state here. + * + * "Message" interrupts will never have "asserted" set + */ + ics = kvmppc_xics_find_ics(xics, irq, &src); + if (!ics) + goto bail; + state = &ics->irq_state[src]; + + /* Still asserted, resend it, we make it look like a reject */ + if (state->asserted) { + icp->rm_action |= XICS_RM_REJECT; + icp->rm_reject = irq; + } + bail: + return check_too_hard(xics, icp); +} diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S index 56f8927b0ddf..fd3b72d5dfe6 100644 --- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S +++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S @@ -1424,11 +1424,19 @@ hcall_real_table: .long 0 /* 0x58 */ .long 0 /* 0x5c */ .long 0 /* 0x60 */ - .long 0 /* 0x64 */ - .long 0 /* 0x68 */ - .long 0 /* 0x6c */ - .long 0 /* 0x70 */ - .long 0 /* 0x74 */ +#ifdef CONFIG_KVM_XICS + .long .kvmppc_rm_h_eoi - hcall_real_table + .long .kvmppc_rm_h_cppr - hcall_real_table + .long .kvmppc_rm_h_ipi - hcall_real_table + .long 0 /* 0x70 - H_IPOLL */ + .long .kvmppc_rm_h_xirr - hcall_real_table +#else + .long 0 /* 0x64 - H_EOI */ + .long 0 /* 0x68 - H_CPPR */ + .long 0 /* 0x6c - H_IPI */ + .long 0 /* 0x70 - H_IPOLL */ + .long 0 /* 0x74 - H_XIRR */ +#endif .long 0 /* 0x78 */ .long 0 /* 0x7c */ .long 0 /* 0x80 */ diff --git a/arch/powerpc/kvm/book3s_xics.c b/arch/powerpc/kvm/book3s_xics.c index 1417e65b6bbd..7fd247cbd0d1 100644 --- a/arch/powerpc/kvm/book3s_xics.c +++ b/arch/powerpc/kvm/book3s_xics.c @@ -30,6 +30,9 @@ #define XICS_DBG(fmt...) trace_printk(fmt) #endif +#define ENABLE_REALMODE true +#define DEBUG_REALMODE false + /* * LOCKING * ======= @@ -220,8 +223,10 @@ static inline bool icp_try_update(struct kvmppc_icp *icp, * in Accept (H_XIRR) and Up_Cppr (H_XPPR). * * We also do not try to figure out whether the EE state has changed, - * we unconditionally set it if the new state calls for it for the - * same reason. + * we unconditionally set it if the new state calls for it. The reason + * for that is that we opportunistically remove the pending interrupt + * flag when raising CPPR, so we need to set it back here if an + * interrupt is still pending. */ if (new.out_ee) { kvmppc_book3s_queue_irqprio(icp->vcpu, @@ -483,7 +488,7 @@ static void icp_down_cppr(struct kvmppc_xics *xics, struct kvmppc_icp *icp, icp_check_resend(xics, icp); } -static noinline unsigned long h_xirr(struct kvm_vcpu *vcpu) +static noinline unsigned long kvmppc_h_xirr(struct kvm_vcpu *vcpu) { union kvmppc_icp_state old_state, new_state; struct kvmppc_icp *icp = vcpu->arch.icp; @@ -517,8 +522,8 @@ static noinline unsigned long h_xirr(struct kvm_vcpu *vcpu) return xirr; } -static noinline int h_ipi(struct kvm_vcpu *vcpu, unsigned long server, - unsigned long mfrr) +static noinline int kvmppc_h_ipi(struct kvm_vcpu *vcpu, unsigned long server, + unsigned long mfrr) { union kvmppc_icp_state old_state, new_state; struct kvmppc_xics *xics = vcpu->kvm->arch.xics; @@ -586,7 +591,7 @@ static noinline int h_ipi(struct kvm_vcpu *vcpu, unsigned long server, return H_SUCCESS; } -static noinline void h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr) +static noinline void kvmppc_h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr) { union kvmppc_icp_state old_state, new_state; struct kvmppc_xics *xics = vcpu->kvm->arch.xics; @@ -643,7 +648,7 @@ static noinline void h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr) icp_deliver_irq(xics, icp, reject); } -static noinline int h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr) +static noinline int kvmppc_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr) { struct kvmppc_xics *xics = vcpu->kvm->arch.xics; struct kvmppc_icp *icp = vcpu->arch.icp; @@ -693,29 +698,54 @@ static noinline int h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr) return H_SUCCESS; } +static noinline int kvmppc_xics_rm_complete(struct kvm_vcpu *vcpu, u32 hcall) +{ + struct kvmppc_xics *xics = vcpu->kvm->arch.xics; + struct kvmppc_icp *icp = vcpu->arch.icp; + + XICS_DBG("XICS_RM: H_%x completing, act: %x state: %lx tgt: %p\n", + hcall, icp->rm_action, icp->rm_dbgstate.raw, icp->rm_dbgtgt); + + if (icp->rm_action & XICS_RM_KICK_VCPU) + kvmppc_fast_vcpu_kick(icp->rm_kick_target); + if (icp->rm_action & XICS_RM_CHECK_RESEND) + icp_check_resend(xics, icp); + if (icp->rm_action & XICS_RM_REJECT) + icp_deliver_irq(xics, icp, icp->rm_reject); + + icp->rm_action = 0; + + return H_SUCCESS; +} + int kvmppc_xics_hcall(struct kvm_vcpu *vcpu, u32 req) { + struct kvmppc_xics *xics = vcpu->kvm->arch.xics; unsigned long res; int rc = H_SUCCESS; /* Check if we have an ICP */ - if (!vcpu->arch.icp || !vcpu->kvm->arch.xics) + if (!xics || !vcpu->arch.icp) return H_HARDWARE; + /* Check for real mode returning too hard */ + if (xics->real_mode) + return kvmppc_xics_rm_complete(vcpu, req); + switch (req) { case H_XIRR: - res = h_xirr(vcpu); + res = kvmppc_h_xirr(vcpu); kvmppc_set_gpr(vcpu, 4, res); break; case H_CPPR: - h_cppr(vcpu, kvmppc_get_gpr(vcpu, 4)); + kvmppc_h_cppr(vcpu, kvmppc_get_gpr(vcpu, 4)); break; case H_EOI: - rc = h_eoi(vcpu, kvmppc_get_gpr(vcpu, 4)); + rc = kvmppc_h_eoi(vcpu, kvmppc_get_gpr(vcpu, 4)); break; case H_IPI: - rc = h_ipi(vcpu, kvmppc_get_gpr(vcpu, 4), - kvmppc_get_gpr(vcpu, 5)); + rc = kvmppc_h_ipi(vcpu, kvmppc_get_gpr(vcpu, 4), + kvmppc_get_gpr(vcpu, 5)); break; } @@ -933,6 +963,14 @@ int kvm_xics_create(struct kvm *kvm, u32 type) xics_debugfs_init(xics); +#ifdef CONFIG_KVM_BOOK3S_64_HV + if (cpu_has_feature(CPU_FTR_ARCH_206)) { + /* Enable real mode support */ + xics->real_mode = ENABLE_REALMODE; + xics->real_mode_dbg = DEBUG_REALMODE; + } +#endif /* CONFIG_KVM_BOOK3S_64_HV */ + return 0; } diff --git a/arch/powerpc/kvm/book3s_xics.h b/arch/powerpc/kvm/book3s_xics.h index 58ee190de5e5..c816c5a49c90 100644 --- a/arch/powerpc/kvm/book3s_xics.h +++ b/arch/powerpc/kvm/book3s_xics.h @@ -64,6 +64,20 @@ struct kvmppc_icp { unsigned long server_num; union kvmppc_icp_state state; unsigned long resend_map[ICP_RESEND_MAP_SIZE]; + + /* Real mode might find something too hard, here's the action + * it might request from virtual mode + */ +#define XICS_RM_KICK_VCPU 0x1 +#define XICS_RM_CHECK_RESEND 0x2 +#define XICS_RM_REJECT 0x4 + u32 rm_action; + struct kvm_vcpu *rm_kick_target; + u32 rm_reject; + + /* Debug stuff for real mode */ + union kvmppc_icp_state rm_dbgstate; + struct kvm_vcpu *rm_dbgtgt; }; struct kvmppc_ics { @@ -76,6 +90,8 @@ struct kvmppc_xics { struct kvm *kvm; struct dentry *dentry; u32 max_icsid; + bool real_mode; + bool real_mode_dbg; struct kvmppc_ics *ics[KVMPPC_XICS_MAX_ICS_ID + 1]; }; |