mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-16 02:06:49 +07:00
4415b33528
The main thing here is a new implementation of the in-kernel XICS interrupt controller emulation for POWER9 machines, from Ben Herrenschmidt. POWER9 has a new interrupt controller called XIVE (eXternal Interrupt Virtualization Engine) which is able to deliver interrupts directly to guest virtual CPUs in hardware without hypervisor intervention. With this new code, the guest still sees the old XICS interface but performance is better because the XICS emulation in the host uses the XIVE directly rather than going through a XICS emulation in firmware. Conflicts: arch/powerpc/kernel/cpu_setup_power.S [cherry-picked fix] arch/powerpc/kvm/book3s_xive.c [include asm/debugfs.h]
924 lines
24 KiB
C
924 lines
24 KiB
C
/*
|
|
* 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 <linux/kernel_stat.h>
|
|
|
|
#include <asm/kvm_book3s.h>
|
|
#include <asm/kvm_ppc.h>
|
|
#include <asm/hvcall.h>
|
|
#include <asm/xics.h>
|
|
#include <asm/synch.h>
|
|
#include <asm/cputhreads.h>
|
|
#include <asm/pgtable.h>
|
|
#include <asm/ppc-opcode.h>
|
|
#include <asm/pnv-pci.h>
|
|
#include <asm/opal.h>
|
|
#include <asm/smp.h>
|
|
|
|
#include "book3s_xics.h"
|
|
|
|
#define DEBUG_PASSUP
|
|
|
|
int h_ipi_redirect = 1;
|
|
EXPORT_SYMBOL(h_ipi_redirect);
|
|
int kvm_irq_bypass = 1;
|
|
EXPORT_SYMBOL(kvm_irq_bypass);
|
|
|
|
static void icp_rm_deliver_irq(struct kvmppc_xics *xics, struct kvmppc_icp *icp,
|
|
u32 new_irq, bool check_resend);
|
|
static int xics_opal_set_server(unsigned int hw_irq, int server_cpu);
|
|
|
|
/* -- ICS routines -- */
|
|
static void ics_rm_check_resend(struct kvmppc_xics *xics,
|
|
struct kvmppc_ics *ics, struct kvmppc_icp *icp)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < KVMPPC_XICS_IRQ_PER_ICS; i++) {
|
|
struct ics_irq_state *state = &ics->irq_state[i];
|
|
if (state->resend)
|
|
icp_rm_deliver_irq(xics, icp, state->number, true);
|
|
}
|
|
|
|
}
|
|
|
|
/* -- ICP routines -- */
|
|
|
|
#ifdef CONFIG_SMP
|
|
static inline void icp_send_hcore_msg(int hcore, struct kvm_vcpu *vcpu)
|
|
{
|
|
int hcpu;
|
|
|
|
hcpu = hcore << threads_shift;
|
|
kvmppc_host_rm_ops_hv->rm_core[hcore].rm_data = vcpu;
|
|
smp_muxed_ipi_set_message(hcpu, PPC_MSG_RM_HOST_ACTION);
|
|
kvmppc_set_host_ipi(hcpu, 1);
|
|
smp_mb();
|
|
kvmhv_rm_send_ipi(hcpu);
|
|
}
|
|
#else
|
|
static inline void icp_send_hcore_msg(int hcore, struct kvm_vcpu *vcpu) { }
|
|
#endif
|
|
|
|
/*
|
|
* We start the search from our current CPU Id in the core map
|
|
* and go in a circle until we get back to our ID looking for a
|
|
* core that is running in host context and that hasn't already
|
|
* been targeted for another rm_host_ops.
|
|
*
|
|
* In the future, could consider using a fairer algorithm (one
|
|
* that distributes the IPIs better)
|
|
*
|
|
* Returns -1, if no CPU could be found in the host
|
|
* Else, returns a CPU Id which has been reserved for use
|
|
*/
|
|
static inline int grab_next_hostcore(int start,
|
|
struct kvmppc_host_rm_core *rm_core, int max, int action)
|
|
{
|
|
bool success;
|
|
int core;
|
|
union kvmppc_rm_state old, new;
|
|
|
|
for (core = start + 1; core < max; core++) {
|
|
old = new = READ_ONCE(rm_core[core].rm_state);
|
|
|
|
if (!old.in_host || old.rm_action)
|
|
continue;
|
|
|
|
/* Try to grab this host core if not taken already. */
|
|
new.rm_action = action;
|
|
|
|
success = cmpxchg64(&rm_core[core].rm_state.raw,
|
|
old.raw, new.raw) == old.raw;
|
|
if (success) {
|
|
/*
|
|
* Make sure that the store to the rm_action is made
|
|
* visible before we return to caller (and the
|
|
* subsequent store to rm_data) to synchronize with
|
|
* the IPI handler.
|
|
*/
|
|
smp_wmb();
|
|
return core;
|
|
}
|
|
}
|
|
|
|
return -1;
|
|
}
|
|
|
|
static inline int find_available_hostcore(int action)
|
|
{
|
|
int core;
|
|
int my_core = smp_processor_id() >> threads_shift;
|
|
struct kvmppc_host_rm_core *rm_core = kvmppc_host_rm_ops_hv->rm_core;
|
|
|
|
core = grab_next_hostcore(my_core, rm_core, cpu_nr_cores(), action);
|
|
if (core == -1)
|
|
core = grab_next_hostcore(core, rm_core, my_core, action);
|
|
|
|
return core;
|
|
}
|
|
|
|
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;
|
|
int cpu;
|
|
int hcore;
|
|
|
|
/* 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, find an available host core to post to wake the VCPU,
|
|
* if we can't find one, set up state to eventually return too hard.
|
|
*/
|
|
cpu = vcpu->arch.thread_cpu;
|
|
if (cpu < 0 || cpu >= nr_cpu_ids) {
|
|
hcore = -1;
|
|
if (kvmppc_host_rm_ops_hv && h_ipi_redirect)
|
|
hcore = find_available_hostcore(XICS_RM_KICK_VCPU);
|
|
if (hcore != -1) {
|
|
icp_send_hcore_msg(hcore, vcpu);
|
|
} else {
|
|
this_icp->rm_action |= XICS_RM_KICK_VCPU;
|
|
this_icp->rm_kick_target = vcpu;
|
|
}
|
|
return;
|
|
}
|
|
|
|
smp_mb();
|
|
kvmhv_rm_send_ipi(cpu);
|
|
}
|
|
|
|
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_check_resend(struct kvmppc_xics *xics,
|
|
struct kvmppc_icp *icp)
|
|
{
|
|
u32 icsid;
|
|
|
|
/* Order this load with the test for need_resend in the caller */
|
|
smp_rmb();
|
|
for_each_set_bit(icsid, icp->resend_map, xics->max_icsid + 1) {
|
|
struct kvmppc_ics *ics = xics->ics[icsid];
|
|
|
|
if (!test_and_clear_bit(icsid, icp->resend_map))
|
|
continue;
|
|
if (!ics)
|
|
continue;
|
|
ics_rm_check_resend(xics, ics, icp);
|
|
}
|
|
}
|
|
|
|
static bool icp_rm_try_to_deliver(struct kvmppc_icp *icp, u32 irq, u8 priority,
|
|
u32 *reject)
|
|
{
|
|
union kvmppc_icp_state old_state, new_state;
|
|
bool success;
|
|
|
|
do {
|
|
old_state = new_state = READ_ONCE(icp->state);
|
|
|
|
*reject = 0;
|
|
|
|
/* See if we can deliver */
|
|
success = new_state.cppr > priority &&
|
|
new_state.mfrr > priority &&
|
|
new_state.pending_pri > priority;
|
|
|
|
/*
|
|
* If we can, check for a rejection and perform the
|
|
* delivery
|
|
*/
|
|
if (success) {
|
|
*reject = new_state.xisr;
|
|
new_state.xisr = irq;
|
|
new_state.pending_pri = priority;
|
|
} else {
|
|
/*
|
|
* If we failed to deliver we set need_resend
|
|
* so a subsequent CPPR state change causes us
|
|
* to try a new delivery.
|
|
*/
|
|
new_state.need_resend = true;
|
|
}
|
|
|
|
} while (!icp_rm_try_update(icp, old_state, new_state));
|
|
|
|
return success;
|
|
}
|
|
|
|
static void icp_rm_deliver_irq(struct kvmppc_xics *xics, struct kvmppc_icp *icp,
|
|
u32 new_irq, bool check_resend)
|
|
{
|
|
struct ics_irq_state *state;
|
|
struct kvmppc_ics *ics;
|
|
u32 reject;
|
|
u16 src;
|
|
|
|
/*
|
|
* This is used both for initial delivery of an interrupt and
|
|
* for subsequent rejection.
|
|
*
|
|
* Rejection can be racy vs. resends. We have evaluated the
|
|
* rejection in an atomic ICP transaction which is now complete,
|
|
* so potentially the ICP can already accept the interrupt again.
|
|
*
|
|
* So we need to retry the delivery. Essentially the reject path
|
|
* boils down to a failed delivery. Always.
|
|
*
|
|
* Now the interrupt could also have moved to a different target,
|
|
* thus we may need to re-do the ICP lookup as well
|
|
*/
|
|
|
|
again:
|
|
/* Get the ICS state and lock it */
|
|
ics = kvmppc_xics_find_ics(xics, new_irq, &src);
|
|
if (!ics) {
|
|
/* Unsafe increment, but this does not need to be accurate */
|
|
xics->err_noics++;
|
|
return;
|
|
}
|
|
state = &ics->irq_state[src];
|
|
|
|
/* Get a lock on the ICS */
|
|
arch_spin_lock(&ics->lock);
|
|
|
|
/* Get our server */
|
|
if (!icp || state->server != icp->server_num) {
|
|
icp = kvmppc_xics_find_server(xics->kvm, state->server);
|
|
if (!icp) {
|
|
/* Unsafe increment again*/
|
|
xics->err_noicp++;
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
if (check_resend)
|
|
if (!state->resend)
|
|
goto out;
|
|
|
|
/* Clear the resend bit of that interrupt */
|
|
state->resend = 0;
|
|
|
|
/*
|
|
* If masked, bail out
|
|
*
|
|
* Note: PAPR doesn't mention anything about masked pending
|
|
* when doing a resend, only when doing a delivery.
|
|
*
|
|
* However that would have the effect of losing a masked
|
|
* interrupt that was rejected and isn't consistent with
|
|
* the whole masked_pending business which is about not
|
|
* losing interrupts that occur while masked.
|
|
*
|
|
* I don't differentiate normal deliveries and resends, this
|
|
* implementation will differ from PAPR and not lose such
|
|
* interrupts.
|
|
*/
|
|
if (state->priority == MASKED) {
|
|
state->masked_pending = 1;
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* Try the delivery, this will set the need_resend flag
|
|
* in the ICP as part of the atomic transaction if the
|
|
* delivery is not possible.
|
|
*
|
|
* Note that if successful, the new delivery might have itself
|
|
* rejected an interrupt that was "delivered" before we took the
|
|
* ics spin lock.
|
|
*
|
|
* In this case we do the whole sequence all over again for the
|
|
* new guy. We cannot assume that the rejected interrupt is less
|
|
* favored than the new one, and thus doesn't need to be delivered,
|
|
* because by the time we exit icp_rm_try_to_deliver() the target
|
|
* processor may well have already consumed & completed it, and thus
|
|
* the rejected interrupt might actually be already acceptable.
|
|
*/
|
|
if (icp_rm_try_to_deliver(icp, new_irq, state->priority, &reject)) {
|
|
/*
|
|
* Delivery was successful, did we reject somebody else ?
|
|
*/
|
|
if (reject && reject != XICS_IPI) {
|
|
arch_spin_unlock(&ics->lock);
|
|
icp->n_reject++;
|
|
new_irq = reject;
|
|
check_resend = 0;
|
|
goto again;
|
|
}
|
|
} else {
|
|
/*
|
|
* We failed to deliver the interrupt we need to set the
|
|
* resend map bit and mark the ICS state as needing a resend
|
|
*/
|
|
state->resend = 1;
|
|
|
|
/*
|
|
* Make sure when checking resend, we don't miss the resend
|
|
* if resend_map bit is seen and cleared.
|
|
*/
|
|
smp_wmb();
|
|
set_bit(ics->icsid, icp->resend_map);
|
|
|
|
/*
|
|
* If the need_resend flag got cleared in the ICP some time
|
|
* between icp_rm_try_to_deliver() atomic update and now, then
|
|
* we know it might have missed the resend_map bit. So we
|
|
* retry
|
|
*/
|
|
smp_mb();
|
|
if (!icp->state.need_resend) {
|
|
state->resend = 0;
|
|
arch_spin_unlock(&ics->lock);
|
|
check_resend = 0;
|
|
goto again;
|
|
}
|
|
}
|
|
out:
|
|
arch_spin_unlock(&ics->lock);
|
|
}
|
|
|
|
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 = READ_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->n_check_resend++;
|
|
icp_rm_check_resend(xics, icp);
|
|
}
|
|
}
|
|
|
|
|
|
unsigned long xics_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 = READ_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 xics_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.
|
|
*
|
|
* ICP state: Check_IPI
|
|
*
|
|
* If the CPPR is less favored, then we might be replacing
|
|
* an interrupt, and thus need to possibly reject it.
|
|
*
|
|
* ICP State: IPI
|
|
*
|
|
* Besides rejecting any pending interrupts, we also
|
|
* update XISR and pending_pri to mark IPI as pending.
|
|
*
|
|
* PAPR does not describe this state, but if the MFRR is being
|
|
* made less favored than its earlier value, there might be
|
|
* a previously-rejected interrupt needing to be resent.
|
|
* Ideally, we would want to resend only if
|
|
* prio(pending_interrupt) < mfrr &&
|
|
* prio(pending_interrupt) < cppr
|
|
* where pending interrupt is the one that was rejected. But
|
|
* we don't have that state, so we simply trigger a resend
|
|
* whenever the MFRR is made less favored.
|
|
*/
|
|
do {
|
|
old_state = new_state = READ_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) {
|
|
resend = new_state.need_resend;
|
|
new_state.need_resend = 0;
|
|
}
|
|
} while (!icp_rm_try_update(icp, old_state, new_state));
|
|
|
|
/* Handle reject in real mode */
|
|
if (reject && reject != XICS_IPI) {
|
|
this_icp->n_reject++;
|
|
icp_rm_deliver_irq(xics, icp, reject, false);
|
|
}
|
|
|
|
/* Handle resends in real mode */
|
|
if (resend) {
|
|
this_icp->n_check_resend++;
|
|
icp_rm_check_resend(xics, icp);
|
|
}
|
|
|
|
return check_too_hard(xics, this_icp);
|
|
}
|
|
|
|
int xics_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 = READ_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));
|
|
|
|
/*
|
|
* Check for rejects. They are handled by doing a new delivery
|
|
* attempt (see comments in icp_rm_deliver_irq).
|
|
*/
|
|
if (reject && reject != XICS_IPI) {
|
|
icp->n_reject++;
|
|
icp_rm_deliver_irq(xics, icp, reject, false);
|
|
}
|
|
bail:
|
|
return check_too_hard(xics, icp);
|
|
}
|
|
|
|
static int ics_rm_eoi(struct kvm_vcpu *vcpu, u32 irq)
|
|
{
|
|
struct kvmppc_xics *xics = vcpu->kvm->arch.xics;
|
|
struct kvmppc_icp *icp = vcpu->arch.icp;
|
|
struct kvmppc_ics *ics;
|
|
struct ics_irq_state *state;
|
|
u16 src;
|
|
u32 pq_old, pq_new;
|
|
|
|
/*
|
|
* ICS EOI handling: For LSI, if P bit is still set, we need to
|
|
* resend it.
|
|
*
|
|
* For MSI, we move Q bit into P (and clear Q). If it is set,
|
|
* resend it.
|
|
*/
|
|
|
|
ics = kvmppc_xics_find_ics(xics, irq, &src);
|
|
if (!ics)
|
|
goto bail;
|
|
|
|
state = &ics->irq_state[src];
|
|
|
|
if (state->lsi)
|
|
pq_new = state->pq_state;
|
|
else
|
|
do {
|
|
pq_old = state->pq_state;
|
|
pq_new = pq_old >> 1;
|
|
} while (cmpxchg(&state->pq_state, pq_old, pq_new) != pq_old);
|
|
|
|
if (pq_new & PQ_PRESENTED)
|
|
icp_rm_deliver_irq(xics, NULL, irq, false);
|
|
|
|
if (!hlist_empty(&vcpu->kvm->irq_ack_notifier_list)) {
|
|
icp->rm_action |= XICS_RM_NOTIFY_EOI;
|
|
icp->rm_eoied_irq = irq;
|
|
}
|
|
|
|
if (state->host_irq) {
|
|
++vcpu->stat.pthru_all;
|
|
if (state->intr_cpu != -1) {
|
|
int pcpu = raw_smp_processor_id();
|
|
|
|
pcpu = cpu_first_thread_sibling(pcpu);
|
|
++vcpu->stat.pthru_host;
|
|
if (state->intr_cpu != pcpu) {
|
|
++vcpu->stat.pthru_bad_aff;
|
|
xics_opal_set_server(state->host_irq, pcpu);
|
|
}
|
|
state->intr_cpu = -1;
|
|
}
|
|
}
|
|
|
|
bail:
|
|
return check_too_hard(xics, icp);
|
|
}
|
|
|
|
int xics_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;
|
|
u32 irq = xirr & 0x00ffffff;
|
|
|
|
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 specifies
|
|
* 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)
|
|
return check_too_hard(xics, icp);
|
|
|
|
return ics_rm_eoi(vcpu, irq);
|
|
}
|
|
|
|
unsigned long eoi_rc;
|
|
|
|
static void icp_eoi(struct irq_chip *c, u32 hwirq, __be32 xirr, bool *again)
|
|
{
|
|
void __iomem *xics_phys;
|
|
int64_t rc;
|
|
|
|
rc = pnv_opal_pci_msi_eoi(c, hwirq);
|
|
|
|
if (rc)
|
|
eoi_rc = rc;
|
|
|
|
iosync();
|
|
|
|
/* EOI it */
|
|
xics_phys = local_paca->kvm_hstate.xics_phys;
|
|
if (xics_phys) {
|
|
__raw_rm_writel(xirr, xics_phys + XICS_XIRR);
|
|
} else {
|
|
rc = opal_int_eoi(be32_to_cpu(xirr));
|
|
*again = rc > 0;
|
|
}
|
|
}
|
|
|
|
static int xics_opal_set_server(unsigned int hw_irq, int server_cpu)
|
|
{
|
|
unsigned int mangle_cpu = get_hard_smp_processor_id(server_cpu) << 2;
|
|
|
|
return opal_set_xive(hw_irq, mangle_cpu, DEFAULT_PRIORITY);
|
|
}
|
|
|
|
/*
|
|
* Increment a per-CPU 32-bit unsigned integer variable.
|
|
* Safe to call in real-mode. Handles vmalloc'ed addresses
|
|
*
|
|
* ToDo: Make this work for any integral type
|
|
*/
|
|
|
|
static inline void this_cpu_inc_rm(unsigned int __percpu *addr)
|
|
{
|
|
unsigned long l;
|
|
unsigned int *raddr;
|
|
int cpu = smp_processor_id();
|
|
|
|
raddr = per_cpu_ptr(addr, cpu);
|
|
l = (unsigned long)raddr;
|
|
|
|
if (REGION_ID(l) == VMALLOC_REGION_ID) {
|
|
l = vmalloc_to_phys(raddr);
|
|
raddr = (unsigned int *)l;
|
|
}
|
|
++*raddr;
|
|
}
|
|
|
|
/*
|
|
* We don't try to update the flags in the irq_desc 'istate' field in
|
|
* here as would happen in the normal IRQ handling path for several reasons:
|
|
* - state flags represent internal IRQ state and are not expected to be
|
|
* updated outside the IRQ subsystem
|
|
* - more importantly, these are useful for edge triggered interrupts,
|
|
* IRQ probing, etc., but we are only handling MSI/MSIx interrupts here
|
|
* and these states shouldn't apply to us.
|
|
*
|
|
* However, we do update irq_stats - we somewhat duplicate the code in
|
|
* kstat_incr_irqs_this_cpu() for this since this function is defined
|
|
* in irq/internal.h which we don't want to include here.
|
|
* The only difference is that desc->kstat_irqs is an allocated per CPU
|
|
* variable and could have been vmalloc'ed, so we can't directly
|
|
* call __this_cpu_inc() on it. The kstat structure is a static
|
|
* per CPU variable and it should be accessible by real-mode KVM.
|
|
*
|
|
*/
|
|
static void kvmppc_rm_handle_irq_desc(struct irq_desc *desc)
|
|
{
|
|
this_cpu_inc_rm(desc->kstat_irqs);
|
|
__this_cpu_inc(kstat.irqs_sum);
|
|
}
|
|
|
|
long kvmppc_deliver_irq_passthru(struct kvm_vcpu *vcpu,
|
|
__be32 xirr,
|
|
struct kvmppc_irq_map *irq_map,
|
|
struct kvmppc_passthru_irqmap *pimap,
|
|
bool *again)
|
|
{
|
|
struct kvmppc_xics *xics;
|
|
struct kvmppc_icp *icp;
|
|
struct kvmppc_ics *ics;
|
|
struct ics_irq_state *state;
|
|
u32 irq;
|
|
u16 src;
|
|
u32 pq_old, pq_new;
|
|
|
|
irq = irq_map->v_hwirq;
|
|
xics = vcpu->kvm->arch.xics;
|
|
icp = vcpu->arch.icp;
|
|
|
|
kvmppc_rm_handle_irq_desc(irq_map->desc);
|
|
|
|
ics = kvmppc_xics_find_ics(xics, irq, &src);
|
|
if (!ics)
|
|
return 2;
|
|
|
|
state = &ics->irq_state[src];
|
|
|
|
/* only MSIs register bypass producers, so it must be MSI here */
|
|
do {
|
|
pq_old = state->pq_state;
|
|
pq_new = ((pq_old << 1) & 3) | PQ_PRESENTED;
|
|
} while (cmpxchg(&state->pq_state, pq_old, pq_new) != pq_old);
|
|
|
|
/* Test P=1, Q=0, this is the only case where we present */
|
|
if (pq_new == PQ_PRESENTED)
|
|
icp_rm_deliver_irq(xics, icp, irq, false);
|
|
|
|
/* EOI the interrupt */
|
|
icp_eoi(irq_desc_get_chip(irq_map->desc), irq_map->r_hwirq, xirr,
|
|
again);
|
|
|
|
if (check_too_hard(xics, icp) == H_TOO_HARD)
|
|
return 2;
|
|
else
|
|
return -2;
|
|
}
|
|
|
|
/* --- Non-real mode XICS-related built-in routines --- */
|
|
|
|
/**
|
|
* Host Operations poked by RM KVM
|
|
*/
|
|
static void rm_host_ipi_action(int action, void *data)
|
|
{
|
|
switch (action) {
|
|
case XICS_RM_KICK_VCPU:
|
|
kvmppc_host_rm_ops_hv->vcpu_kick(data);
|
|
break;
|
|
default:
|
|
WARN(1, "Unexpected rm_action=%d data=%p\n", action, data);
|
|
break;
|
|
}
|
|
|
|
}
|
|
|
|
void kvmppc_xics_ipi_action(void)
|
|
{
|
|
int core;
|
|
unsigned int cpu = smp_processor_id();
|
|
struct kvmppc_host_rm_core *rm_corep;
|
|
|
|
core = cpu >> threads_shift;
|
|
rm_corep = &kvmppc_host_rm_ops_hv->rm_core[core];
|
|
|
|
if (rm_corep->rm_data) {
|
|
rm_host_ipi_action(rm_corep->rm_state.rm_action,
|
|
rm_corep->rm_data);
|
|
/* Order these stores against the real mode KVM */
|
|
rm_corep->rm_data = NULL;
|
|
smp_wmb();
|
|
rm_corep->rm_state.rm_action = 0;
|
|
}
|
|
}
|