--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2021 Western Digital Corporation or its affiliates.
+ * Copyright (C) 2022 Ventana Micro Systems Inc.
+ *
+ * Authors:
+ * Anup Patel <apatel@ventanamicro.com>
+ */
+
+#include <linux/kvm_host.h>
+#include <linux/math.h>
+#include <linux/spinlock.h>
+#include <linux/swab.h>
+#include <kvm/iodev.h>
+#include <asm/kvm_aia_aplic.h>
+
+struct aplic_irq {
+ raw_spinlock_t lock;
+ u32 sourcecfg;
+ u32 state;
+#define APLIC_IRQ_STATE_PENDING BIT(0)
+#define APLIC_IRQ_STATE_ENABLED BIT(1)
+#define APLIC_IRQ_STATE_ENPEND (APLIC_IRQ_STATE_PENDING | \
+ APLIC_IRQ_STATE_ENABLED)
+#define APLIC_IRQ_STATE_INPUT BIT(8)
+ u32 target;
+};
+
+struct aplic {
+ struct kvm_io_device iodev;
+
+ u32 domaincfg;
+ u32 genmsi;
+
+ u32 nr_irqs;
+ u32 nr_words;
+ struct aplic_irq *irqs;
+};
+
+static u32 aplic_read_sourcecfg(struct aplic *aplic, u32 irq)
+{
+ u32 ret;
+ unsigned long flags;
+ struct aplic_irq *irqd;
+
+ if (!irq || aplic->nr_irqs <= irq)
+ return 0;
+ irqd = &aplic->irqs[irq];
+
+ raw_spin_lock_irqsave(&irqd->lock, flags);
+ ret = irqd->sourcecfg;
+ raw_spin_unlock_irqrestore(&irqd->lock, flags);
+
+ return ret;
+}
+
+static void aplic_write_sourcecfg(struct aplic *aplic, u32 irq, u32 val)
+{
+ unsigned long flags;
+ struct aplic_irq *irqd;
+
+ if (!irq || aplic->nr_irqs <= irq)
+ return;
+ irqd = &aplic->irqs[irq];
+
+ if (val & APLIC_SOURCECFG_D)
+ val = 0;
+ else
+ val &= APLIC_SOURCECFG_SM_MASK;
+
+ raw_spin_lock_irqsave(&irqd->lock, flags);
+ irqd->sourcecfg = val;
+ raw_spin_unlock_irqrestore(&irqd->lock, flags);
+}
+
+static u32 aplic_read_target(struct aplic *aplic, u32 irq)
+{
+ u32 ret;
+ unsigned long flags;
+ struct aplic_irq *irqd;
+
+ if (!irq || aplic->nr_irqs <= irq)
+ return 0;
+ irqd = &aplic->irqs[irq];
+
+ raw_spin_lock_irqsave(&irqd->lock, flags);
+ ret = irqd->target;
+ raw_spin_unlock_irqrestore(&irqd->lock, flags);
+
+ return ret;
+}
+
+static void aplic_write_target(struct aplic *aplic, u32 irq, u32 val)
+{
+ unsigned long flags;
+ struct aplic_irq *irqd;
+
+ if (!irq || aplic->nr_irqs <= irq)
+ return;
+ irqd = &aplic->irqs[irq];
+
+ val &= APLIC_TARGET_EIID_MASK |
+ (APLIC_TARGET_HART_IDX_MASK << APLIC_TARGET_HART_IDX_SHIFT) |
+ (APLIC_TARGET_GUEST_IDX_MASK << APLIC_TARGET_GUEST_IDX_SHIFT);
+
+ raw_spin_lock_irqsave(&irqd->lock, flags);
+ irqd->target = val;
+ raw_spin_unlock_irqrestore(&irqd->lock, flags);
+}
+
+static bool aplic_read_pending(struct aplic *aplic, u32 irq)
+{
+ bool ret;
+ unsigned long flags;
+ struct aplic_irq *irqd;
+
+ if (!irq || aplic->nr_irqs <= irq)
+ return false;
+ irqd = &aplic->irqs[irq];
+
+ raw_spin_lock_irqsave(&irqd->lock, flags);
+ ret = (irqd->state & APLIC_IRQ_STATE_PENDING) ? true : false;
+ raw_spin_unlock_irqrestore(&irqd->lock, flags);
+
+ return ret;
+}
+
+static void aplic_write_pending(struct aplic *aplic, u32 irq, bool pending)
+{
+ unsigned long flags, sm;
+ struct aplic_irq *irqd;
+
+ if (!irq || aplic->nr_irqs <= irq)
+ return;
+ irqd = &aplic->irqs[irq];
+
+ raw_spin_lock_irqsave(&irqd->lock, flags);
+
+ sm = irqd->sourcecfg & APLIC_SOURCECFG_SM_MASK;
+ if (!pending &&
+ ((sm == APLIC_SOURCECFG_SM_LEVEL_HIGH) ||
+ (sm == APLIC_SOURCECFG_SM_LEVEL_LOW)))
+ goto skip_write_pending;
+
+ if (pending)
+ irqd->state |= APLIC_IRQ_STATE_PENDING;
+ else
+ irqd->state &= ~APLIC_IRQ_STATE_PENDING;
+
+skip_write_pending:
+ raw_spin_unlock_irqrestore(&irqd->lock, flags);
+}
+
+static bool aplic_read_enabled(struct aplic *aplic, u32 irq)
+{
+ bool ret;
+ unsigned long flags;
+ struct aplic_irq *irqd;
+
+ if (!irq || aplic->nr_irqs <= irq)
+ return false;
+ irqd = &aplic->irqs[irq];
+
+ raw_spin_lock_irqsave(&irqd->lock, flags);
+ ret = (irqd->state & APLIC_IRQ_STATE_ENABLED) ? true : false;
+ raw_spin_unlock_irqrestore(&irqd->lock, flags);
+
+ return ret;
+}
+
+static void aplic_write_enabled(struct aplic *aplic, u32 irq, bool enabled)
+{
+ unsigned long flags;
+ struct aplic_irq *irqd;
+
+ if (!irq || aplic->nr_irqs <= irq)
+ return;
+ irqd = &aplic->irqs[irq];
+
+ raw_spin_lock_irqsave(&irqd->lock, flags);
+ if (enabled)
+ irqd->state |= APLIC_IRQ_STATE_ENABLED;
+ else
+ irqd->state &= ~APLIC_IRQ_STATE_ENABLED;
+ raw_spin_unlock_irqrestore(&irqd->lock, flags);
+}
+
+static bool aplic_read_input(struct aplic *aplic, u32 irq)
+{
+ bool ret;
+ unsigned long flags;
+ struct aplic_irq *irqd;
+
+ if (!irq || aplic->nr_irqs <= irq)
+ return false;
+ irqd = &aplic->irqs[irq];
+
+ raw_spin_lock_irqsave(&irqd->lock, flags);
+ ret = (irqd->state & APLIC_IRQ_STATE_INPUT) ? true : false;
+ raw_spin_unlock_irqrestore(&irqd->lock, flags);
+
+ return ret;
+}
+
+static void aplic_inject_msi(struct kvm *kvm, u32 irq, u32 target)
+{
+ u32 hart_idx, guest_idx, eiid;
+
+ hart_idx = target >> APLIC_TARGET_HART_IDX_SHIFT;
+ hart_idx &= APLIC_TARGET_HART_IDX_MASK;
+ guest_idx = target >> APLIC_TARGET_GUEST_IDX_SHIFT;
+ guest_idx &= APLIC_TARGET_GUEST_IDX_MASK;
+ eiid = target & APLIC_TARGET_EIID_MASK;
+ kvm_riscv_aia_inject_msi_by_id(kvm, hart_idx, guest_idx, eiid);
+}
+
+static void aplic_update_irq_range(struct kvm *kvm, u32 first, u32 last)
+{
+ bool inject;
+ u32 irq, target;
+ unsigned long flags;
+ struct aplic_irq *irqd;
+ struct aplic *aplic = kvm->arch.aia.aplic_state;
+
+ if (!(aplic->domaincfg & APLIC_DOMAINCFG_IE))
+ return;
+
+ for (irq = first; irq <= last; irq++) {
+ if (!irq || aplic->nr_irqs <= irq)
+ continue;
+ irqd = &aplic->irqs[irq];
+
+ raw_spin_lock_irqsave(&irqd->lock, flags);
+
+ inject = false;
+ target = irqd->target;
+ if ((irqd->state & APLIC_IRQ_STATE_ENPEND) ==
+ APLIC_IRQ_STATE_ENPEND) {
+ irqd->state &= ~APLIC_IRQ_STATE_PENDING;
+ inject = true;
+ }
+
+ raw_spin_unlock_irqrestore(&irqd->lock, flags);
+
+ if (inject)
+ aplic_inject_msi(kvm, irq, target);
+ }
+}
+
+int kvm_riscv_aia_aplic_inject(struct kvm *kvm, u32 source, bool level)
+{
+ u32 target;
+ bool inject = false, ie;
+ unsigned long flags;
+ struct aplic_irq *irqd;
+ struct aplic *aplic = kvm->arch.aia.aplic_state;
+
+ if (!aplic || !source || (aplic->nr_irqs <= source))
+ return -ENODEV;
+ irqd = &aplic->irqs[source];
+ ie = (aplic->domaincfg & APLIC_DOMAINCFG_IE) ? true : false;
+
+ raw_spin_lock_irqsave(&irqd->lock, flags);
+
+ if (irqd->sourcecfg & APLIC_SOURCECFG_D)
+ goto skip_unlock;
+
+ switch (irqd->sourcecfg & APLIC_SOURCECFG_SM_MASK) {
+ case APLIC_SOURCECFG_SM_EDGE_RISE:
+ if (level && !(irqd->state & APLIC_IRQ_STATE_INPUT) &&
+ !(irqd->state & APLIC_IRQ_STATE_PENDING))
+ irqd->state |= APLIC_IRQ_STATE_PENDING;
+ break;
+ case APLIC_SOURCECFG_SM_EDGE_FALL:
+ if (!level && (irqd->state & APLIC_IRQ_STATE_INPUT) &&
+ !(irqd->state & APLIC_IRQ_STATE_PENDING))
+ irqd->state |= APLIC_IRQ_STATE_PENDING;
+ break;
+ case APLIC_SOURCECFG_SM_LEVEL_HIGH:
+ if (level && !(irqd->state & APLIC_IRQ_STATE_PENDING))
+ irqd->state |= APLIC_IRQ_STATE_PENDING;
+ break;
+ case APLIC_SOURCECFG_SM_LEVEL_LOW:
+ if (!level && !(irqd->state & APLIC_IRQ_STATE_PENDING))
+ irqd->state |= APLIC_IRQ_STATE_PENDING;
+ break;
+ }
+
+ if (level)
+ irqd->state |= APLIC_IRQ_STATE_INPUT;
+ else
+ irqd->state &= ~APLIC_IRQ_STATE_INPUT;
+
+ target = irqd->target;
+ if (ie && ((irqd->state & APLIC_IRQ_STATE_ENPEND) ==
+ APLIC_IRQ_STATE_ENPEND)) {
+ irqd->state &= ~APLIC_IRQ_STATE_PENDING;
+ inject = true;
+ }
+
+skip_unlock:
+ raw_spin_unlock_irqrestore(&irqd->lock, flags);
+
+ if (inject)
+ aplic_inject_msi(kvm, source, target);
+
+ return 0;
+}
+
+static u32 aplic_read_input_word(struct aplic *aplic, u32 word)
+{
+ u32 i, ret = 0;
+
+ for (i = 0; i < 32; i++)
+ ret |= aplic_read_input(aplic, word * 32 + i) ? BIT(i) : 0;
+
+ return ret;
+}
+
+static u32 aplic_read_pending_word(struct aplic *aplic, u32 word)
+{
+ u32 i, ret = 0;
+
+ for (i = 0; i < 32; i++)
+ ret |= aplic_read_pending(aplic, word * 32 + i) ? BIT(i) : 0;
+
+ return ret;
+}
+
+static void aplic_write_pending_word(struct aplic *aplic, u32 word,
+ u32 val, bool pending)
+{
+ u32 i;
+
+ for (i = 0; i < 32; i++) {
+ if (val & BIT(i))
+ aplic_write_pending(aplic, word * 32 + i, pending);
+ }
+}
+
+static u32 aplic_read_enabled_word(struct aplic *aplic, u32 word)
+{
+ u32 i, ret = 0;
+
+ for (i = 0; i < 32; i++)
+ ret |= aplic_read_enabled(aplic, word * 32 + i) ? BIT(i) : 0;
+
+ return ret;
+}
+
+static void aplic_write_enabled_word(struct aplic *aplic, u32 word,
+ u32 val, bool enabled)
+{
+ u32 i;
+
+ for (i = 0; i < 32; i++) {
+ if (val & BIT(i))
+ aplic_write_enabled(aplic, word * 32 + i, enabled);
+ }
+}
+
+static int aplic_mmio_read_offset(struct kvm *kvm, gpa_t off, u32 *val32)
+{
+ u32 i;
+ struct aplic *aplic = kvm->arch.aia.aplic_state;
+
+ if ((off & 0x3) != 0)
+ return -EOPNOTSUPP;
+
+ if (off == APLIC_DOMAINCFG) {
+ *val32 = APLIC_DOMAINCFG_RDONLY |
+ aplic->domaincfg | APLIC_DOMAINCFG_DM;
+ } else if ((off >= APLIC_SOURCECFG_BASE) &&
+ (off < (APLIC_SOURCECFG_BASE + (aplic->nr_irqs - 1) * 4))) {
+ i = ((off - APLIC_SOURCECFG_BASE) >> 2) + 1;
+ *val32 = aplic_read_sourcecfg(aplic, i);
+ } else if ((off >= APLIC_SETIP_BASE) &&
+ (off < (APLIC_SETIP_BASE + aplic->nr_words * 4))) {
+ i = (off - APLIC_SETIP_BASE) >> 2;
+ *val32 = aplic_read_pending_word(aplic, i);
+ } else if (off == APLIC_SETIPNUM) {
+ *val32 = 0;
+ } else if ((off >= APLIC_CLRIP_BASE) &&
+ (off < (APLIC_CLRIP_BASE + aplic->nr_words * 4))) {
+ i = (off - APLIC_CLRIP_BASE) >> 2;
+ *val32 = aplic_read_input_word(aplic, i);
+ } else if (off == APLIC_CLRIPNUM) {
+ *val32 = 0;
+ } else if ((off >= APLIC_SETIE_BASE) &&
+ (off < (APLIC_SETIE_BASE + aplic->nr_words * 4))) {
+ i = (off - APLIC_SETIE_BASE) >> 2;
+ *val32 = aplic_read_enabled_word(aplic, i);
+ } else if (off == APLIC_SETIENUM) {
+ *val32 = 0;
+ } else if ((off >= APLIC_CLRIE_BASE) &&
+ (off < (APLIC_CLRIE_BASE + aplic->nr_words * 4))) {
+ *val32 = 0;
+ } else if (off == APLIC_CLRIENUM) {
+ *val32 = 0;
+ } else if (off == APLIC_SETIPNUM_LE) {
+ *val32 = 0;
+ } else if (off == APLIC_SETIPNUM_BE) {
+ *val32 = 0;
+ } else if (off == APLIC_GENMSI) {
+ *val32 = aplic->genmsi;
+ } else if ((off >= APLIC_TARGET_BASE) &&
+ (off < (APLIC_TARGET_BASE + (aplic->nr_irqs - 1) * 4))) {
+ i = ((off - APLIC_TARGET_BASE) >> 2) + 1;
+ *val32 = aplic_read_target(aplic, i);
+ } else
+ return -ENODEV;
+
+ return 0;
+}
+
+static int aplic_mmio_read(struct kvm_vcpu *vcpu, struct kvm_io_device *dev,
+ gpa_t addr, int len, void *val)
+{
+ if (len != 4)
+ return -EOPNOTSUPP;
+
+ return aplic_mmio_read_offset(vcpu->kvm,
+ addr - vcpu->kvm->arch.aia.aplic_addr,
+ val);
+}
+
+static int aplic_mmio_write_offset(struct kvm *kvm, gpa_t off, u32 val32)
+{
+ u32 i;
+ struct aplic *aplic = kvm->arch.aia.aplic_state;
+
+ if ((off & 0x3) != 0)
+ return -EOPNOTSUPP;
+
+ if (off == APLIC_DOMAINCFG) {
+ /* Only IE bit writeable */
+ aplic->domaincfg = val32 & APLIC_DOMAINCFG_IE;
+ } else if ((off >= APLIC_SOURCECFG_BASE) &&
+ (off < (APLIC_SOURCECFG_BASE + (aplic->nr_irqs - 1) * 4))) {
+ i = ((off - APLIC_SOURCECFG_BASE) >> 2) + 1;
+ aplic_write_sourcecfg(aplic, i, val32);
+ } else if ((off >= APLIC_SETIP_BASE) &&
+ (off < (APLIC_SETIP_BASE + aplic->nr_words * 4))) {
+ i = (off - APLIC_SETIP_BASE) >> 2;
+ aplic_write_pending_word(aplic, i, val32, true);
+ } else if (off == APLIC_SETIPNUM) {
+ aplic_write_pending(aplic, val32, true);
+ } else if ((off >= APLIC_CLRIP_BASE) &&
+ (off < (APLIC_CLRIP_BASE + aplic->nr_words * 4))) {
+ i = (off - APLIC_CLRIP_BASE) >> 2;
+ aplic_write_pending_word(aplic, i, val32, false);
+ } else if (off == APLIC_CLRIPNUM) {
+ aplic_write_pending(aplic, val32, false);
+ } else if ((off >= APLIC_SETIE_BASE) &&
+ (off < (APLIC_SETIE_BASE + aplic->nr_words * 4))) {
+ i = (off - APLIC_SETIE_BASE) >> 2;
+ aplic_write_enabled_word(aplic, i, val32, true);
+ } else if (off == APLIC_SETIENUM) {
+ aplic_write_enabled(aplic, val32, true);
+ } else if ((off >= APLIC_CLRIE_BASE) &&
+ (off < (APLIC_CLRIE_BASE + aplic->nr_words * 4))) {
+ i = (off - APLIC_CLRIE_BASE) >> 2;
+ aplic_write_enabled_word(aplic, i, val32, false);
+ } else if (off == APLIC_CLRIENUM) {
+ aplic_write_enabled(aplic, val32, false);
+ } else if (off == APLIC_SETIPNUM_LE) {
+ aplic_write_pending(aplic, val32, true);
+ } else if (off == APLIC_SETIPNUM_BE) {
+ aplic_write_pending(aplic, __swab32(val32), true);
+ } else if (off == APLIC_GENMSI) {
+ aplic->genmsi = val32 & ~(APLIC_TARGET_GUEST_IDX_MASK <<
+ APLIC_TARGET_GUEST_IDX_SHIFT);
+ kvm_riscv_aia_inject_msi_by_id(kvm,
+ val32 >> APLIC_TARGET_HART_IDX_SHIFT, 0,
+ val32 & APLIC_TARGET_EIID_MASK);
+ } else if ((off >= APLIC_TARGET_BASE) &&
+ (off < (APLIC_TARGET_BASE + (aplic->nr_irqs - 1) * 4))) {
+ i = ((off - APLIC_TARGET_BASE) >> 2) + 1;
+ aplic_write_target(aplic, i, val32);
+ } else
+ return -ENODEV;
+
+ aplic_update_irq_range(kvm, 1, aplic->nr_irqs - 1);
+
+ return 0;
+}
+
+static int aplic_mmio_write(struct kvm_vcpu *vcpu, struct kvm_io_device *dev,
+ gpa_t addr, int len, const void *val)
+{
+ if (len != 4)
+ return -EOPNOTSUPP;
+
+ return aplic_mmio_write_offset(vcpu->kvm,
+ addr - vcpu->kvm->arch.aia.aplic_addr,
+ *((const u32 *)val));
+}
+
+static struct kvm_io_device_ops aplic_iodoev_ops = {
+ .read = aplic_mmio_read,
+ .write = aplic_mmio_write,
+};
+
+int kvm_riscv_aia_aplic_init(struct kvm *kvm)
+{
+ int i, ret = 0;
+ struct aplic *aplic;
+
+ /* Do nothing if we have zero sources */
+ if (!kvm->arch.aia.nr_sources)
+ return 0;
+
+ /* Allocate APLIC global state */
+ aplic = kzalloc(sizeof(*aplic), GFP_KERNEL);
+ if (!aplic)
+ return -ENOMEM;
+ kvm->arch.aia.aplic_state = aplic;
+
+ /* Setup APLIC IRQs */
+ aplic->nr_irqs = kvm->arch.aia.nr_sources + 1;
+ aplic->nr_words = DIV_ROUND_UP(aplic->nr_irqs, 32);
+ aplic->irqs = kcalloc(aplic->nr_irqs,
+ sizeof(*aplic->irqs), GFP_KERNEL);
+ if (!aplic->irqs) {
+ ret = -ENOMEM;
+ goto fail_free_aplic;
+ }
+ for (i = 0; i < aplic->nr_irqs; i++)
+ raw_spin_lock_init(&aplic->irqs[i].lock);
+
+ /* Setup IO device */
+ kvm_iodevice_init(&aplic->iodev, &aplic_iodoev_ops);
+ mutex_lock(&kvm->slots_lock);
+ ret = kvm_io_bus_register_dev(kvm, KVM_MMIO_BUS,
+ kvm->arch.aia.aplic_addr,
+ KVM_DEV_RISCV_APLIC_SIZE,
+ &aplic->iodev);
+ mutex_unlock(&kvm->slots_lock);
+ if (ret)
+ goto fail_free_aplic_irqs;
+
+ /* Setup default IRQ routing */
+ ret = kvm_riscv_setup_default_irq_routing(kvm, aplic->nr_irqs);
+ if (ret)
+ goto fail_unreg_iodev;
+
+ return 0;
+
+fail_unreg_iodev:
+ mutex_lock(&kvm->slots_lock);
+ kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS, &aplic->iodev);
+ mutex_unlock(&kvm->slots_lock);
+fail_free_aplic_irqs:
+ kfree(aplic->irqs);
+fail_free_aplic:
+ kvm->arch.aia.aplic_state = NULL;
+ kfree(aplic);
+ return ret;
+}
+
+void kvm_riscv_aia_aplic_cleanup(struct kvm *kvm)
+{
+ struct aplic *aplic = kvm->arch.aia.aplic_state;
+
+ if (!aplic)
+ return;
+
+ mutex_lock(&kvm->slots_lock);
+ kvm_io_bus_unregister_dev(kvm, KVM_MMIO_BUS, &aplic->iodev);
+ mutex_unlock(&kvm->slots_lock);
+
+ kfree(aplic->irqs);
+
+ kvm->arch.aia.aplic_state = NULL;
+ kfree(aplic);
+}