/*
* Copyright (C) 2012 ARM Ltd.
* Author: Marc Zyngier <marc.zyngier@arm.com>
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/cpu.h>
#include <linux/kvm.h>
#include <linux/kvm_host.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/irqchip/arm-gic.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_mmu.h>
/*
* How the whole thing works (courtesy of Christoffer Dall):
*
* - At any time, the dist->irq_pending_on_cpu is the oracle that knows if
* something is pending
* - VGIC pending interrupts are stored on the vgic.irq_state vgic
* bitmap (this bitmap is updated by both user land ioctls and guest
* mmio ops, and other in-kernel peripherals such as the
* arch. timers) and indicate the 'wire' state.
* - Every time the bitmap changes, the irq_pending_on_cpu oracle is
* recalculated
* - To calculate the oracle, we need info for each cpu from
* compute_pending_for_cpu, which considers:
* - PPI: dist->irq_state & dist->irq_enable
* - SPI: dist->irq_state & dist->irq_enable & dist->irq_spi_target
* - irq_spi_target is a 'formatted' version of the GICD_ICFGR
* registers, stored on each vcpu. We only keep one bit of
* information per interrupt, making sure that only one vcpu can
* accept the interrupt.
* - The same is true when injecting an interrupt, except that we only
* consider a single interrupt at a time. The irq_spi_cpu array
* contains the target CPU for each SPI.
*
* The handling of level interrupts adds some extra complexity. We
* need to track when the interrupt has been EOIed, so we can sample
* the 'line' again. This is achieved as such:
*
* - When a level interrupt is moved onto a vcpu, the corresponding
* bit in irq_active is set. As long as this bit is set, the line
* will be ignored for further interrupts. The interrupt is injected
* into the vcpu with the GICH_LR_EOI bit set (generate a
* maintenance interrupt on EOI).
* - When the interrupt is EOIed, the maintenance interrupt fires,
* and clears the corresponding bit in irq_active. This allow the
* interrupt line to be sampled again.
*/
#define VGIC_ADDR_UNDEF (-1)
#define IS_VGIC_ADDR_UNDEF(_x) ((_x) == VGIC_ADDR_UNDEF)
/* Physical address of vgic virtual cpu interface */
static phys_addr_t vgic_vcpu_base;
/* Virtual control interface base address */
static void __iomem *vgic_vctrl_base;
static struct device_node *vgic_node;
#define ACCESS_READ_VALUE (1 << 0)
#define ACCESS_READ_RAZ (0 << 0)
#define ACCESS_READ_MASK(x) ((x) & (1 << 0))
#define ACCESS_WRITE_IGNORED (0 << 1)
#define ACCESS_WRITE_SETBIT (1 << 1)
#define ACCESS_WRITE_CLEARBIT (2 << 1)
#define ACCESS_WRITE_VALUE (3 << 1)
#define ACCESS_WRITE_MASK(x) ((x) & (3 << 1))
static void vgic_retire_disabled_irqs(struct kvm_vcpu *vcpu);
static void vgic_update_state(struct kvm *kvm);
static void vgic_kick_vcpus(struct kvm *kvm);
static void vgic_dispatch_sgi(struct kvm_vcpu *vcpu, u32 reg);
static u32 vgic_nr_lr;
static unsigned int vgic_maint_irq;
static u32 *vgic_bitmap_get_reg(struct vgic_bitmap *x,
int cpuid, u32 offset)
{
offset >>= 2;
if (!offset)
return x->percpu[cpuid].reg;
else
return x->shared.reg + offset - 1;
}
static int vgic_bitmap_get_irq_val(struct vgic_bitmap *x,
int cpuid, int irq)
{
if (irq < VGIC_NR_PRIVATE_IRQS)
return test_bit(irq, x->percpu[cpuid].reg_ul);
return test_bit(irq - VGIC_NR_PRIVATE_IRQS, x->shared.reg_ul);
}
static void vgic_bitmap_set_irq_val(struct vgic_bitmap *x, int cpuid,
int irq, int val)
{
unsigned long *reg;
if (irq < VGIC_NR_PRIVATE_IRQS) {
reg = x->percpu[cpuid].reg_ul;
} else {
reg = x->shared.reg_ul;
irq -= VGIC_NR_PRIVATE_IRQS;
}
if (val)
set_bit(irq, reg);
else
clear_bit(irq, reg);
}
static unsigned long *vgic_bitmap_get_cpu_map(struct vgic_bitmap *x, int cpuid)
{
if (unlikely(cpuid >= VGIC_MAX_CPUS))
return NULL;
return x->percpu[cpuid].reg_ul;
}
static unsigned long *vgic_bitmap_get_shared_map(struct vgic_bitmap *x)
{
return x->shared.reg_ul;
}
static u32 *vgic_bytemap_get_reg(struct vgic_bytemap *x, int cpuid, u32 offset)
{
offset >>= 2;
BUG_ON(offset > (VGIC_NR_IRQS / 4));
if (offset < 4)
return x->percpu[cpuid] + offset;
else
return x->shared + offset - 8;
}
#define VGIC_CFG_LEVEL 0
#define VGIC_CFG_EDGE 1
static bool vgic_irq_is_edge(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
int irq_val;
irq_val = vgic_bitmap_get_irq_val(&dist->irq_cfg, vcpu->vcpu_id, irq);
return irq_val == VGIC_CFG_EDGE;
}
static int vgic_irq_is_enabled(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
return vgic_bitmap_get_irq_val(&dist->irq_enabled, vcpu->vcpu_id, irq);
}
static int vgic_irq_is_active(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
return vgic_bitmap_get_irq_val(&dist->irq_active, vcpu->vcpu_id, irq);
}
static void vgic_irq_set_active(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
vgic_bitmap_set_irq_val(&dist->irq_active, vcpu->vcpu_id, irq, 1);
}
static void vgic_irq_clear_active(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
vgic_bitmap_set_irq_val(&dist->irq_active, vcpu->vcpu_id, irq, 0);
}
static int vgic_dist_irq_is_pending(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
return vgic_bitmap_get_irq_val(&dist->irq_state, vcpu->vcpu_id, irq);
}
static void vgic_dist_irq_set(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
vgic_bitmap_set_irq_val(&dist->irq_state, vcpu->vcpu_id, irq, 1);
}
static void vgic_dist_irq_clear(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
vgic_bitmap_set_irq_val(&dist->irq_state, vcpu->vcpu_id, irq, 0);
}
static void vgic_cpu_irq_set(struct kvm_vcpu *vcpu, int irq)
{
if (irq < VGIC_NR_PRIVATE_IRQS)
set_bit(irq, vcpu->arch.vgic_cpu.pending_percpu);
else
set_bit(irq - VGIC_NR_PRIVATE_IRQS,
vcpu->arch.vgic_cpu.pending_shared);
}
static void vgic_cpu_irq_clear(struct kvm_vcpu *vcpu, int irq)
{
if (irq < VGIC_NR_PRIVATE_IRQS)
clear_bit(irq, vcpu->arch.vgic_cpu.pending_percpu);
else
clear_bit(irq - VGIC_NR_PRIVATE_IRQS,
vcpu->arch.vgic_cpu.pending_shared);
}
static u32 mmio_data_read(struct kvm_exit_mmio *mmio, u32 mask)
{
return *((u32 *)mmio->data) & mask;
}
static void mmio_data_write(struct kvm_exit_mmio *mmio, u32 mask, u32 value)
{
*((u32 *)mmio->data) = value & mask;
}
/**
* vgic_reg_access - access vgic register
* @mmio: pointer to the data describing the mmio access
* @reg: pointer to the virtual backing of vgic distributor data
* @offset: least significant 2 bits used for word offset
* @mode: ACCESS_ mode (see defines above)
*
* Helper to make vgic register access easier using one of the access
* modes defined for vgic register access
* (read,raz,write-ignored,setbit,clearbit,write)
*/
static void vgic_reg_access(struct kvm_exit_mmio *mmio, u32 *reg,
phys_addr_t offset, int mode)
{
int word_offset = (offset & 3) * 8;
u32 mask = (1UL << (mmio->len * 8)) - 1;
u32 regval;
/*
* Any alignment fault should have been delivered to the guest
* directly (ARM ARM B3.12.7 "Prioritization of aborts").
*/
if (reg) {
regval = *reg;
} else {
BUG_ON(mode != (ACCESS_READ_RAZ | ACCESS_WRITE_IGNORED));
regval = 0;
}
if (mmio->is_write) {
u32 data = mmio_data_read(mmio, mask) << word_offset;
switch (ACCESS_WRITE_MASK(mode)) {
case ACCESS_WRITE_IGNORED:
return;
case ACCESS_WRITE_SETBIT:
regval |= data;
break;
case ACCESS_WRITE_CLEARBIT:
regval &= ~data;
break;
case ACCESS_WRITE_VALUE:
regval = (regval & ~(mask << word_offset)) | data;
break;
}
*reg = regval;
} else {
switch (ACCESS_READ_MASK(mode)) {
case ACCESS_READ_RAZ:
regval = 0;
/* fall through */
case ACCESS_READ_VALUE:
mmio_data_write(mmio, mask, regval >> word_offset);
}
}
}
static bool handle_mmio_misc(struct kvm_vcpu *vcpu,
struct kvm_exit_mmio *mmio, phys_addr_t offset)
{
u32 reg;
u32 word_offset = offset & 3;
switch (offset & ~3) {
case 0: /* CTLR */
reg = vcpu->kvm->arch.vgic.enabled;
vgic_reg_access(mmio, ®, word_offset,
ACCESS_READ_VALUE | ACCESS_WRITE_VALUE);
if (mmio->is_write) {
vcpu->kvm->arch.vgic.enabled = reg & 1;
vgic_update_state(vcpu->kvm);
return true;
}
break;
case 4: /* TYPER */
reg = (atomic_read(&vcpu->kvm->online_vcpus) - 1) << 5;
reg |= (VGIC_NR_IRQS >> 5) - 1;
vgic_reg_access(mmio, ®, word_offset,
ACCESS_READ_VALUE | ACCESS_WRITE_IGNORED);
break;
case 8: /* IIDR */
reg = 0x4B00043B;
vgic_reg_access(mmio, ®, word_offset,
ACCESS_READ_VALUE | ACCESS_WRITE_IGNORED);
break;
}
return false;
}
static bool handle_mmio_raz_wi(struct kvm_vcpu *vcpu,
struct kvm_exit_mmio *mmio, phys_addr_t offset)
{
vgic_reg_access(mmio, NULL, offset,
ACCESS_READ_RAZ | ACCESS_WRITE_IGNORED);
return false;
}
static bool handle_mmio_set_enable_reg(struct kvm_vcpu *vcpu,
struct kvm_exit_mmio *mmio,
phys_addr_t offset)
{
u32 *reg = vgic_bitmap_get_reg(&vcpu->kvm->arch.vgic.irq_enabled,
vcpu->vcpu_id, offset);
vgic_reg_access(mmio, reg, offset,
ACCESS_READ_VALUE | ACCESS_WRITE_SETBIT);
if (mmio->is_write) {
vgic_update_state(vcpu->kvm);
return true;
}
return false;
}
static bool handle_mmio_clear_enable_reg(struct kvm_vcpu *vcpu,
struct kvm_exit_mmio *mmio,
phys_addr_t offset)
{
u32 *reg = vgic_bitmap_get_reg(&vcpu->kvm->arch.vgic.irq_enabled,
vcpu->vcpu_id, offset);
vgic_reg_access(mmio, reg, offset,
ACCESS_READ_VALUE | ACCESS_WRITE_CLEARBIT);
if (mmio->is_write) {
if (offset < 4) /* Force SGI enabled */
*reg |= 0xffff;
vgic_retire_disabled_irqs(vcpu);
vgic_update_state(vcpu->kvm);
return true;
}
return false;
}
static bool handle_mmio_set_pending_reg(struct kvm_vcpu *vcpu,
struct kvm_exit_mmio *mmio,
phys_addr_t offset)
{
u32 *reg = vgic_bitmap_get_reg(&vcpu->kvm->arch.vgic.irq_state,
vcpu->vcpu_id, offset);
vgic_reg_access(mmio, reg, offset,
ACCESS_READ_VALUE | ACCESS_WRITE_SETBIT);
if (mmio->is_write) {
vgic_update_state(vcpu->kvm);
return true;
}
return false;
}
static bool handle_mmio_clear_pending_reg(struct kvm_vcpu *vcpu,
struct kvm_exit_mmio *mmio,
phys_addr_t offset)
{
u32 *reg = vgic_bitmap_get_reg(&vcpu->kvm->arch.vgic.irq_state,
vcpu->vcpu_id, offset);
vgic_reg_access(mmio, reg, offset,
ACCESS_READ_VALUE | ACCESS_WRITE_CLEARBIT);
if (mmio->is_write) {
vgic_update_state(vcpu->kvm);
return true;
}
return false;
}
static bool handle_mmio_priority_reg(struct kvm_vcpu *vcpu,
struct kvm_exit_mmio *mmio,
phys_addr_t offset)
{
u32 *reg = vgic_bytemap_get_reg(&vcpu->kvm->arch.vgic.irq_priority,
vcpu->vcpu_id, offset);
vgic_reg_access(mmio, reg, offset,
ACCESS_READ_VALUE | ACCESS_WRITE_VALUE);
return false;
}
#define GICD_ITARGETSR_SIZE 32
#define GICD_CPUTARGETS_BITS 8
#define GICD_IRQS_PER_ITARGETSR (GICD_ITARGETSR_SIZE / GICD_CPUTARGETS_BITS)
static u32 vgic_get_target_reg(struct kvm *kvm, int irq)
{
struct vgic_dist *dist = &kvm->arch.vgic;
struct kvm_vcpu *vcpu;
int i, c;
unsigned long *bmap;
u32 val = 0;
irq -= VGIC_NR_PRIVATE_IRQS;
kvm_for_each_vcpu(c, vcpu, kvm) {
bmap = vgic_bitmap_get_shared_map(&dist->irq_spi_target[c]);
for (i = 0; i < GICD_IRQS_PER_ITARGETSR; i++)
if (test_bit(irq + i, bmap))
val |= 1 << (c + i * 8);
}
return val;
}
static void vgic_set_target_reg(struct kvm *kvm, u32 val, int irq)
{
struct vgic_dist *dist = &kvm->arch.vgic;
struct kvm_vcpu *vcpu;
int i, c;
unsigned long *bmap;
u32 target;
irq -= VGIC_NR_PRIVATE_IRQS;
/*
* Pick the LSB in each byte. This ensures we target exactly
* one vcpu per IRQ. If the byte is null, assume we target
* CPU0.
*/
for (i = 0; i < GICD_IRQS_PER_ITARGETSR; i++) {
int shift = i * GICD_CPUTARGETS_BITS;
target = ffs((val >> shift) & 0xffU);
target = target ? (target - 1) : 0;
dist->irq_spi_cpu[irq + i] = target;
kvm_for_each_vcpu(c, vcpu, kvm) {
bmap = vgic_bitmap_get_shared_map(&dist->irq_spi_target[c]);
if (c == target)
set_bit(irq + i, bmap);
else
clear_bit(irq + i, bmap);
}
}
}
static bool handle_mmio_target_reg(struct kvm_vcpu *vcpu,
struct kvm_exit_mmio *mmio,
phys_addr_t offset)
{
u32 reg;
/* We treat the banked interrupts targets as read-only */
if (offset < 32) {
u32 roreg = 1 << vcpu->vcpu_id;
roreg |= roreg << 8;
roreg |= roreg << 16;
vgic_reg_access(mmio, &roreg, offset,
ACCESS_READ_VALUE | ACCESS_WRITE_IGNORED);
return false;
}
reg = vgic_get_target_reg(vcpu->kvm, offset & ~3U);
vgic_reg_access(mmio, ®, offset,
ACCESS_READ_VALUE | ACCESS_WRITE_VALUE);
if (mmio->is_write) {
vgic_set_target_reg(vcpu->kvm, reg, offset & ~3U);
vgic_update_state(vcpu->kvm);
return true;
}
return false;
}
static u32 vgic_cfg_expand(u16 val)
{
u32 res = 0;
int i;
/*
* Turn a 16bit value like abcd...mnop into a 32bit word
* a0b0c0d0...m0n0o0p0, which is what the HW cfg register is.
*/
for (i = 0; i < 16; i++)
res |= ((val >> i) & VGIC_CFG_EDGE) << (2 * i + 1);
return res;
}
static u16 vgic_cfg_compress(u32 val)
{
u16 res = 0;
int i;
/*
* Turn a 32bit word a0b0c0d0...m0n0o0p0 into 16bit value like
* abcd...mnop which is what we really care about.
*/
for (i = 0; i < 16; i++)
res |= ((val >> (i * 2 + 1)) & VGIC_CFG_EDGE) << i;
return res;
}
/*
* The distributor uses 2 bits per IRQ for the CFG register, but the
* LSB is always 0. As such, we only keep the upper bit, and use the
* two above functions to compress/expand the bits
*/
static bool handle_mmio_cfg_reg(struct kvm_vcpu *vcpu,
struct kvm_exit_mmio *mmio, phys_addr_t offset)
{
u32 val;
u32 *reg = vgic_bitmap_get_reg(&vcpu->kvm->arch.vgic.irq_cfg,
vcpu->vcpu_id, offset >> 1);
if (offset & 2)
val = *reg >> 16;
else
val = *reg & 0xffff;
val = vgic_cfg_expand(val);
vgic_reg_access(mmio, &val, offset,
ACCESS_READ_VALUE | ACCESS_WRITE_VALUE);
if (mmio->is_write) {
if (offset < 4) {
*reg = ~0U; /* Force PPIs/SGIs to 1 */
return false;
}
val = vgic_cfg_compress(val);
if (offset & 2) {
*reg &= 0xffff;
*reg |= val << 16;
} else {
*reg &= 0xffff << 16;
*reg |= val;
}
}
return false;
}
static bool handle_mmio_sgi_reg(struct kvm_vcpu *vcpu,
struct kvm_exit_mmio *mmio, phys_addr_t offset)
{
u32 reg;
vgic_reg_access(mmio, ®, offset,
ACCESS_READ_RAZ | ACCESS_WRITE_VALUE);
if (mmio->is_write) {
vgic_dispatch_sgi(vcpu, reg);
vgic_update_state(vcpu->kvm);
return true;
}
return false;
}
/*
* I would have liked to use the kvm_bus_io_*() API instead, but it
* cannot cope with banked registers (only the VM pointer is passed
* around, and we need the vcpu). One of these days, someone please
* fix it!
*/
struct mmio_range {
phys_addr_t base;
unsigned long len;
bool (*handle_mmio)(struct kvm_vcpu *vcpu, struct kvm_exit_mmio *mmio,
phys_addr_t offset);
};
static const struct mmio_range vgic_ranges[] = {
{
.base = GIC_DIST_CTRL,
.len = 12,
.handle_mmio = handle_mmio_misc,
},
{
.base = GIC_DIST_IGROUP,
.len = VGIC_NR_IRQS / 8,
.handle_mmio = handle_mmio_raz_wi,
},
{
.base = GIC_DIST_ENABLE_SET,
.len = VGIC_NR_IRQS / 8,
.handle_mmio = handle_mmio_set_enable_reg,
},
{
.base = GIC_DIST_ENABLE_CLEAR,
.len = VGIC_NR_IRQS / 8,
.handle_mmio = handle_mmio_clear_enable_reg,
},
{
.base = GIC_DIST_PENDING_SET,
.len = VGIC_NR_IRQS / 8,
.handle_mmio = handle_mmio_set_pending_reg,
},
{
.base = GIC_DIST_PENDING_CLEAR,
.len = VGIC_NR_IRQS / 8,
.handle_mmio = handle_mmio_clear_pending_reg,
},
{
.base = GIC_DIST_ACTIVE_SET,
.len = VGIC_NR_IRQS / 8,
.handle_mmio = handle_mmio_raz_wi,
},
{
.base = GIC_DIST_ACTIVE_CLEAR,
.len = VGIC_NR_IRQS / 8,
.handle_mmio = handle_mmio_raz_wi,
},
{
.base = GIC_DIST_PRI,
.len = VGIC_NR_IRQS,
.handle_mmio = handle_mmio_priority_reg,
},
{
.base = GIC_DIST_TARGET,
.len = VGIC_NR_IRQS,
.handle_mmio = handle_mmio_target_reg,
},
{
.base = GIC_DIST_CONFIG,
.len = VGIC_NR_IRQS / 4,
.handle_mmio = handle_mmio_cfg_reg,
},
{
.base = GIC_DIST_SOFTINT,
.len = 4,
.handle_mmio = handle_mmio_sgi_reg,
},
{}
};
static const
struct mmio_range *find_matching_range(const struct mmio_range *ranges,
struct kvm_exit_mmio *mmio,
phys_addr_t base)
{
const struct mmio_range *r = ranges;
phys_addr_t addr = mmio->phys_addr - base;
while (r->len) {
if (addr >= r->base &&
(addr + mmio->len) <= (r->base + r->len))
return r;
r++;
}
return NULL;
}
/**
* vgic_handle_mmio - handle an in-kernel MMIO access
* @vcpu: pointer to the vcpu performing the access
* @run: pointer to the kvm_run structure
* @mmio: pointer to the data describing the access
*
* returns true if the MMIO access has been performed in kernel space,
* and false if it needs to be emulated in user space.
*/
bool vgic_handle_mmio(struct kvm_vcpu *vcpu, struct kvm_run *run,
struct kvm_exit_mmio *mmio)
{
const struct mmio_range *range;
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
unsigned long base = dist->vgic_dist_base;
bool updated_state;
unsigned long offset;
if (!irqchip_in_kernel(vcpu->kvm) ||
mmio->phys_addr < base ||
(mmio->phys_addr + mmio->len) > (base + KVM_VGIC_V2_DIST_SIZE))
return false;
/* We don't support ldrd / strd or ldm / stm to the emulated vgic */
if (mmio->len > 4) {
kvm_inject_dabt(vcpu, mmio->phys_addr);
return true;
}
range = find_matching_range(vgic_ranges, mmio, base);
if (unlikely(!range || !range->handle_mmio)) {
pr_warn("Unhandled access %d %08llx %d\n",
mmio->is_write, mmio->phys_addr, mmio->len);
return false;
}
spin_lock(&vcpu->kvm->arch.vgic.lock);
offset = mmio->phys_addr - range->base - base;
updated_state = range->handle_mmio(vcpu, mmio, offset);
spin_unlock(&vcpu->kvm->arch.vgic.lock);
kvm_prepare_mmio(run, mmio);
kvm_handle_mmio_return(vcpu, run);
if (updated_state)
vgic_kick_vcpus(vcpu->kvm);
return true;
}
static void vgic_dispatch_sgi(struct kvm_vcpu *vcpu, u32 reg)
{
struct kvm *kvm = vcpu->kvm;
struct vgic_dist *dist = &kvm->arch.vgic;
int nrcpus = atomic_read(&kvm->online_vcpus);
u8 target_cpus;
int sgi, mode, c, vcpu_id;
vcpu_id = vcpu->vcpu_id;
sgi = reg & 0xf;
target_cpus = (reg >> 16) & 0xff;
mode = (reg >> 24) & 3;
switch (mode) {
case 0:
if (!target_cpus)
return;
case 1:
target_cpus = ((1 << nrcpus) - 1) & ~(1 << vcpu_id) & 0xff;
break;
case 2:
target_cpus = 1 << vcpu_id;
break;
}
kvm_for_each_vcpu(c, vcpu, kvm) {
if (target_cpus & 1) {
/* Flag the SGI as pending */
vgic_dist_irq_set(vcpu, sgi);
dist->irq_sgi_sources[c][sgi] |= 1 << vcpu_id;
kvm_debug("SGI%d from CPU%d to CPU%d\n", sgi, vcpu_id, c);
}
target_cpus >>= 1;
}
}
static int compute_pending_for_cpu(struct kvm_vcpu *vcpu)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
unsigned long *pending, *enabled, *pend_percpu, *pend_shared;
unsigned long pending_private, pending_shared;
int vcpu_id;
vcpu_id = vcpu->vcpu_id;
pend_percpu = vcpu->arch.vgic_cpu.pending_percpu;
pend_shared = vcpu->arch.vgic_cpu.pending_shared;
pending = vgic_bitmap_get_cpu_map(&dist->irq_state, vcpu_id);
enabled = vgic_bitmap_get_cpu_map(&dist->irq_enabled, vcpu_id);
bitmap_and(pend_percpu, pending, enabled, VGIC_NR_PRIVATE_IRQS);
pending = vgic_bitmap_get_shared_map(&dist->irq_state);
enabled = vgic_bitmap_get_shared_map(&dist->irq_enabled);
bitmap_and(pend_shared, pending, enabled, VGIC_NR_SHARED_IRQS);
bitmap_and(pend_shared, pend_shared,
vgic_bitmap_get_shared_map(&dist->irq_spi_target[vcpu_id]),
VGIC_NR_SHARED_IRQS);
pending_private = find_first_bit(pend_percpu, VGIC_NR_PRIVATE_IRQS);
pending_shared = find_first_bit(pend_shared, VGIC_NR_SHARED_IRQS);
return (pending_private < VGIC_NR_PRIVATE_IRQS ||
pending_shared < VGIC_NR_SHARED_IRQS);
}
/*
* Update the interrupt state and determine which CPUs have pending
* interrupts. Must be called with distributor lock held.
*/
static void vgic_update_state(struct kvm *kvm)
{
struct vgic_dist *dist = &kvm->arch.vgic;
struct kvm_vcpu *vcpu;
int c;
if (!dist->enabled) {
set_bit(0, &dist->irq_pending_on_cpu);
return;
}
kvm_for_each_vcpu(c, vcpu, kvm) {
if (compute_pending_for_cpu(vcpu)) {
pr_debug("CPU%d has pending interrupts\n", c);
set_bit(c, &dist->irq_pending_on_cpu);
}
}
}
#define LR_CPUID(lr) \
(((lr) & GICH_LR_PHYSID_CPUID) >> GICH_LR_PHYSID_CPUID_SHIFT)
#define MK_LR_PEND(src, irq) \
(GICH_LR_PENDING_BIT | ((src) << GICH_LR_PHYSID_CPUID_SHIFT) | (irq))
/*
* An interrupt may have been disabled after being made pending on the
* CPU interface (the classic case is a timer running while we're
* rebooting the guest - the interrupt would kick as soon as the CPU
* interface gets enabled, with deadly consequences).
*
* The solution is to examine already active LRs, and check the
* interrupt is still enabled. If not, just retire it.
*/
static void vgic_retire_disabled_irqs(struct kvm_vcpu *vcpu)
{
struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
int lr;
for_each_set_bit(lr, vgic_cpu->lr_used, vgic_cpu->nr_lr) {
int irq = vgic_cpu->vgic_lr[lr] & GICH_LR_VIRTUALID;
if (!vgic_irq_is_enabled(vcpu, irq)) {
vgic_cpu->vgic_irq_lr_map[irq] = LR_EMPTY;
clear_bit(lr, vgic_cpu->lr_used);
vgic_cpu->vgic_lr[lr] &= ~GICH_LR_STATE;
if (vgic_irq_is_active(vcpu, irq))
vgic_irq_clear_active(vcpu, irq);
}
}
}
/*
* Queue an interrupt to a CPU virtual interface. Return true on success,
* or false if it wasn't possible to queue it.
*/
static bool vgic_queue_irq(struct kvm_vcpu *vcpu, u8 sgi_source_id, int irq)
{
struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
int lr;
/* Sanitize the input... */
BUG_ON(sgi_source_id & ~7);
BUG_ON(sgi_source_id && irq >= VGIC_NR_SGIS);
BUG_ON(irq >= VGIC_NR_IRQS);
kvm_debug("Queue IRQ%d\n", irq);
lr = vgic_cpu->vgic_irq_lr_map[irq];
/* Do we have an active interrupt for the same CPUID? */
if (lr != LR_EMPTY &&
(LR_CPUID(vgic_cpu->vgic_lr[lr]) == sgi_source_id)) {
kvm_debug("LR%d piggyback for IRQ%d %x\n",
lr, irq, vgic_cpu->vgic_lr[lr]);
BUG_ON(!test_bit(lr, vgic_cpu->lr_used));
vgic_cpu->vgic_lr[lr] |= GICH_LR_PENDING_BIT;
return true;
}
/* Try to use another LR for this interrupt */
lr = find_first_zero_bit((unsigned long *)vgic_cpu->lr_used,
vgic_cpu->nr_lr);
if (lr >= vgic_cpu->nr_lr)
return false;
kvm_debug("LR%d allocated for IRQ%d %x\n", lr, irq, sgi_source_id);
vgic_cpu->vgic_lr[lr] = MK_LR_PEND(sgi_source_id, irq);
vgic_cpu->vgic_irq_lr_map[irq] = lr;
set_bit(lr, vgic_cpu->lr_used);
if (!vgic_irq_is_edge(vcpu, irq))
vgic_cpu->vgic_lr[lr] |= GICH_LR_EOI;
return true;
}
static bool vgic_queue_sgi(struct kvm_vcpu *vcpu, int irq)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
unsigned long sources;
int vcpu_id = vcpu->vcpu_id;
int c;
sources = dist->irq_sgi_sources[vcpu_id][irq];
for_each_set_bit(c, &sources, VGIC_MAX_CPUS) {
if (vgic_queue_irq(vcpu, c, irq))
clear_bit(c, &sources);
}
dist->irq_sgi_sources[vcpu_id][irq] = sources;
/*
* If the sources bitmap has been cleared it means that we
* could queue all the SGIs onto link registers (see the
* clear_bit above), and therefore we are done with them in
* our emulated gic and can get rid of them.
*/
if (!sources) {
vgic_dist_irq_clear(vcpu, irq);
vgic_cpu_irq_clear(vcpu, irq);
return true;
}
return false;
}
static bool vgic_queue_hwirq(struct kvm_vcpu *vcpu, int irq)
{
if (vgic_irq_is_active(vcpu, irq))
return true; /* level interrupt, already queued */
if (vgic_queue_irq(vcpu, 0, irq)) {
if (vgic_irq_is_edge(vcpu, irq)) {
vgic_dist_irq_clear(vcpu, irq);
vgic_cpu_irq_clear(vcpu, irq);
} else {
vgic_irq_set_active(vcpu, irq);
}
return true;
}
return false;
}
/*
* Fill the list registers with pending interrupts before running the
* guest.
*/
static void __kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu)
{
struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
int i, vcpu_id;
int overflow = 0;
vcpu_id = vcpu->vcpu_id;
/*
* We may not have any pending interrupt, or the interrupts
* may have been serviced from another vcpu. In all cases,
* move along.
*/
if (!kvm_vgic_vcpu_pending_irq(vcpu)) {
pr_debug("CPU%d has no pending interrupt\n", vcpu_id);
goto epilog;
}
/* SGIs */
for_each_set_bit(i, vgic_cpu->pending_percpu, VGIC_NR_SGIS) {
if (!vgic_queue_sgi(vcpu, i))
overflow = 1;
}
/* PPIs */
for_each_set_bit_from(i, vgic_cpu->pending_percpu, VGIC_NR_PRIVATE_IRQS) {
if (!vgic_queue_hwirq(vcpu, i))
overflow = 1;
}
/* SPIs */
for_each_set_bit(i, vgic_cpu->pending_shared, VGIC_NR_SHARED_IRQS) {
if (!vgic_queue_hwirq(vcpu, i + VGIC_NR_PRIVATE_IRQS))
overflow = 1;
}
epilog:
if (overflow) {
vgic_cpu->vgic_hcr |= GICH_HCR_UIE;
} else {
vgic_cpu->vgic_hcr &= ~GICH_HCR_UIE;
/*
* We're about to run this VCPU, and we've consumed
* everything the distributor had in store for
* us. Claim we don't have anything pending. We'll
* adjust that if needed while exiting.
*/
clear_bit(vcpu_id, &dist->irq_pending_on_cpu);
}
}
static bool vgic_process_maintenance(struct kvm_vcpu *vcpu)
{
struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
bool level_pending = false;
kvm_debug("MISR = %08x\n", vgic_cpu->vgic_misr);
if (vgic_cpu->vgic_misr & GICH_MISR_EOI) {
/*
* Some level interrupts have been EOIed. Clear their
* active bit.
*/
int lr, irq;
for_each_set_bit(lr, (unsigned long *)vgic_cpu->vgic_eisr,
vgic_cpu->nr_lr) {
irq = vgic_cpu->vgic_lr[lr] & GICH_LR_VIRTUALID;
vgic_irq_clear_active(vcpu, irq);
vgic_cpu->vgic_lr[lr] &= ~GICH_LR_EOI;
/* Any additional pending interrupt? */
if (vgic_dist_irq_is_pending(vcpu, irq)) {
vgic_cpu_irq_set(vcpu, irq);
level_pending = true;
} else {
vgic_cpu_irq_clear(vcpu, irq);
}
/*
* Despite being EOIed, the LR may not have
* been marked as empty.
*/
set_bit(lr, (unsigned long *)vgic_cpu->vgic_elrsr);
vgic_cpu->vgic_lr[lr] &= ~GICH_LR_ACTIVE_BIT;
}
}
if (vgic_cpu->vgic_misr & GICH_MISR_U)
vgic_cpu->vgic_hcr &= ~GICH_HCR_UIE;
return level_pending;
}
/*
* Sync back the VGIC state after a guest run. The distributor lock is
* needed so we don't get preempted in the middle of the state processing.
*/
static void __kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu)
{
struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
int lr, pending;
bool level_pending;
level_pending = vgic_process_maintenance(vcpu);
/* Clear mappings for empty LRs */
for_each_set_bit(lr, (unsigned long *)vgic_cpu->vgic_elrsr,
vgic_cpu->nr_lr) {
int irq;
if (!test_and_clear_bit(lr, vgic_cpu->lr_used))
continue;
irq = vgic_cpu->vgic_lr[lr] & GICH_LR_VIRTUALID;
BUG_ON(irq >= VGIC_NR_IRQS);
vgic_cpu->vgic_irq_lr_map[irq] = LR_EMPTY;
}
/* Check if we still have something up our sleeve... */
pending = find_first_zero_bit((unsigned long *)vgic_cpu->vgic_elrsr,
vgic_cpu->nr_lr);
if (level_pending || pending < vgic_cpu->nr_lr)
set_bit(vcpu->vcpu_id, &dist->irq_pending_on_cpu);
}
void kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
if (!irqchip_in_kernel(vcpu->kvm))
return;
spin_lock(&dist->lock);
__kvm_vgic_flush_hwstate(vcpu);
spin_unlock(&dist->lock);
}
void kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
if (!irqchip_in_kernel(vcpu->kvm))
return;
spin_lock(&dist->lock);
__kvm_vgic_sync_hwstate(vcpu);
spin_unlock(&dist->lock);
}
int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu)
{
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
if (!irqchip_in_kernel(vcpu->kvm))
return 0;
return test_bit(vcpu->vcpu_id, &dist->irq_pending_on_cpu);
}
static void vgic_kick_vcpus(struct kvm *kvm)
{
struct kvm_vcpu *vcpu;
int c;
/*
* We've injected an interrupt, time to find out who deserves
* a good kick...
*/
kvm_for_each_vcpu(c, vcpu, kvm) {
if (kvm_vgic_vcpu_pending_irq(vcpu))
kvm_vcpu_kick(vcpu);
}
}
static int vgic_validate_injection(struct kvm_vcpu *vcpu, int irq, int level)
{
int is_edge = vgic_irq_is_edge(vcpu, irq);
int state = vgic_dist_irq_is_pending(vcpu, irq);
/*
* Only inject an interrupt if:
* - edge triggered and we have a rising edge
* - level triggered and we change level
*/
if (is_edge)
return level > state;
else
return level != state;
}
static bool vgic_update_irq_state(struct kvm *kvm, int cpuid,
unsigned int irq_num, bool level)
{
struct vgic_dist *dist = &kvm->arch.vgic;
struct kvm_vcpu *vcpu;
int is_edge, is_level;
int enabled;
bool ret = true;
spin_lock(&dist->lock);
vcpu = kvm_get_vcpu(kvm, cpuid);
is_edge = vgic_irq_is_edge(vcpu, irq_num);
is_level = !is_edge;
if (!vgic_validate_injection(vcpu, irq_num, level)) {
ret = false;
goto out;
}
if (irq_num >= VGIC_NR_PRIVATE_IRQS) {
cpuid = dist->irq_spi_cpu[irq_num - VGIC_NR_PRIVATE_IRQS];
vcpu = kvm_get_vcpu(kvm, cpuid);
}
kvm_debug("Inject IRQ%d level %d CPU%d\n", irq_num, level, cpuid);
if (level)
vgic_dist_irq_set(vcpu, irq_num);
else
vgic_dist_irq_clear(vcpu, irq_num);
enabled = vgic_irq_is_enabled(vcpu, irq_num);
if (!enabled) {
ret = false;
goto out;
}
if (is_level && vgic_irq_is_active(vcpu, irq_num)) {
/*
* Level interrupt in progress, will be picked up
* when EOId.
*/
ret = false;
goto out;
}
if (level) {
vgic_cpu_irq_set(vcpu, irq_num);
set_bit(cpuid, &dist->irq_pending_on_cpu);
}
out:
spin_unlock(&dist->lock);
return ret;
}
/**
* kvm_vgic_inject_irq - Inject an IRQ from a device to the vgic
* @kvm: The VM structure pointer
* @cpuid: The CPU for PPIs
* @irq_num: The IRQ number that is assigned to the device
* @level: Edge-triggered: true: to trigger the interrupt
* false: to ignore the call
* Level-sensitive true: activates an interrupt
* false: deactivates an interrupt
*
* The GIC is not concerned with devices being active-LOW or active-HIGH for
* level-sensitive interrupts. You can think of the level parameter as 1
* being HIGH and 0 being LOW and all devices being active-HIGH.
*/
int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int irq_num,
bool level)
{
if (vgic_update_irq_state(kvm, cpuid, irq_num, level))
vgic_kick_vcpus(kvm);
return 0;
}
static irqreturn_t vgic_maintenance_handler(int irq, void *data)
{
/*
* We cannot rely on the vgic maintenance interrupt to be
* delivered synchronously. This means we can only use it to
* exit the VM, and we perform the handling of EOIed
* interrupts on the exit path (see vgic_process_maintenance).
*/
return IRQ_HANDLED;
}
int kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu)
{
struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
int i;
if (!irqchip_in_kernel(vcpu->kvm))
return 0;
if (vcpu->vcpu_id >= VGIC_MAX_CPUS)
return -EBUSY;
for (i = 0; i < VGIC_NR_IRQS; i++) {
if (i < VGIC_NR_PPIS)
vgic_bitmap_set_irq_val(&dist->irq_enabled,
vcpu->vcpu_id, i, 1);
if (i < VGIC_NR_PRIVATE_IRQS)
vgic_bitmap_set_irq_val(&dist->irq_cfg,
vcpu->vcpu_id, i, VGIC_CFG_EDGE);
vgic_cpu->vgic_irq_lr_map[i] = LR_EMPTY;
}
/*
* By forcing VMCR to zero, the GIC will restore the binary
* points to their reset values. Anything else resets to zero
* anyway.
*/
vgic_cpu->vgic_vmcr = 0;
vgic_cpu->nr_lr = vgic_nr_lr;
vgic_cpu->vgic_hcr = GICH_HCR_EN; /* Get the show on the road... */
return 0;
}
static void vgic_init_maintenance_interrupt(void *info)
{
enable_percpu_irq(vgic_maint_irq, 0);
}
static int vgic_cpu_notify(struct notifier_block *self,
unsigned long action, void *cpu)
{
switch (action) {
case CPU_STARTING:
case CPU_STARTING_FROZEN:
vgic_init_maintenance_interrupt(NULL);
break;
case CPU_DYING:
case CPU_DYING_FROZEN:
disable_percpu_irq(vgic_maint_irq);
break;
}
return NOTIFY_OK;
}
static struct notifier_block vgic_cpu_nb = {
.notifier_call = vgic_cpu_notify,
};
int kvm_vgic_hyp_init(void)
{
int ret;
struct resource vctrl_res;
struct resource vcpu_res;
vgic_node = of_find_compatible_node(NULL, NULL, "arm,cortex-a15-gic");
if (!vgic_node) {
kvm_err("error: no compatible vgic node in DT\n");
return -ENODEV;
}
vgic_maint_irq = irq_of_parse_and_map(vgic_node, 0);
if (!vgic_maint_irq) {
kvm_err("error getting vgic maintenance irq from DT\n");
ret = -ENXIO;
goto out;
}
ret = request_percpu_irq(vgic_maint_irq, vgic_maintenance_handler,
"vgic", kvm_get_running_vcpus());
if (ret) {
kvm_err("Cannot register interrupt %d\n", vgic_maint_irq);
goto out;
}
ret = register_cpu_notifier(&vgic_cpu_nb);
if (ret) {
kvm_err("Cannot register vgic CPU notifier\n");
goto out_free_irq;
}
ret = of_address_to_resource(vgic_node, 2, &vctrl_res);
if (ret) {
kvm_err("Cannot obtain VCTRL resource\n");
goto out_free_irq;
}
vgic_vctrl_base = of_iomap(vgic_node, 2);
if (!vgic_vctrl_base) {
kvm_err("Cannot ioremap VCTRL\n");
ret = -ENOMEM;
goto out_free_irq;
}
vgic_nr_lr = readl_relaxed(vgic_vctrl_base + GICH_VTR);
vgic_nr_lr = (vgic_nr_lr & 0x3f) + 1;
ret = create_hyp_io_mappings(vgic_vctrl_base,
vgic_vctrl_base + resource_size(&vctrl_res),
vctrl_res.start);
if (ret) {
kvm_err("Cannot map VCTRL into hyp\n");
goto out_unmap;
}
kvm_info("%s@%llx IRQ%d\n", vgic_node->name,
vctrl_res.start, vgic_maint_irq);
on_each_cpu(vgic_init_maintenance_interrupt, NULL, 1);
if (of_address_to_resource(vgic_node, 3, &vcpu_res)) {
kvm_err("Cannot obtain VCPU resource\n");
ret = -ENXIO;
goto out_unmap;
}
vgic_vcpu_base = vcpu_res.start;
goto out;
out_unmap:
iounmap(vgic_vctrl_base);
out_free_irq:
free_percpu_irq(vgic_maint_irq, kvm_get_running_vcpus());
out:
of_node_put(vgic_node);
return ret;
}
int kvm_vgic_init(struct kvm *kvm)
{
int ret = 0, i;
mutex_lock(&kvm->lock);
if (vgic_initialized(kvm))
goto out;
if (IS_VGIC_ADDR_UNDEF(kvm->arch.vgic.vgic_dist_base) ||
IS_VGIC_ADDR_UNDEF(kvm->arch.vgic.vgic_cpu_base)) {
kvm_err("Need to set vgic cpu and dist addresses first\n");
ret = -ENXIO;
goto out;
}
ret = kvm_phys_addr_ioremap(kvm, kvm->arch.vgic.vgic_cpu_base,
vgic_vcpu_base, KVM_VGIC_V2_CPU_SIZE);
if (ret) {
kvm_err("Unable to remap VGIC CPU to VCPU\n");
goto out;
}
for (i = VGIC_NR_PRIVATE_IRQS; i < VGIC_NR_IRQS; i += 4)
vgic_set_target_reg(kvm, 0, i);
kvm_timer_init(kvm);
kvm->arch.vgic.ready = true;
out:
mutex_unlock(&kvm->lock);
return ret;
}
int kvm_vgic_create(struct kvm *kvm)
{
int ret = 0;
mutex_lock(&kvm->lock);
if (atomic_read(&kvm->online_vcpus) || kvm->arch.vgic.vctrl_base) {
ret = -EEXIST;
goto out;
}
spin_lock_init(&kvm->arch.vgic.lock);
kvm->arch.vgic.vctrl_base = vgic_vctrl_base;
kvm->arch.vgic.vgic_dist_base = VGIC_ADDR_UNDEF;
kvm->arch.vgic.vgic_cpu_base = VGIC_ADDR_UNDEF;
out:
mutex_unlock(&kvm->lock);
return ret;
}
static bool vgic_ioaddr_overlap(struct kvm *kvm)
{
phys_addr_t dist = kvm->arch.vgic.vgic_dist_base;
phys_addr_t cpu = kvm->arch.vgic.vgic_cpu_base;
if (IS_VGIC_ADDR_UNDEF(dist) || IS_VGIC_ADDR_UNDEF(cpu))
return 0;
if ((dist <= cpu && dist + KVM_VGIC_V2_DIST_SIZE > cpu) ||
(cpu <= dist && cpu + KVM_VGIC_V2_CPU_SIZE > dist))
return -EBUSY;
return 0;
}
static int vgic_ioaddr_assign(struct kvm *kvm, phys_addr_t *ioaddr,
phys_addr_t addr, phys_addr_t size)
{
int ret;
if (!IS_VGIC_ADDR_UNDEF(*ioaddr))
return -EEXIST;
if (addr + size < addr)
return -EINVAL;
ret = vgic_ioaddr_overlap(kvm);
if (ret)
return ret;
*ioaddr = addr;
return ret;
}
int kvm_vgic_set_addr(struct kvm *kvm, unsigned long type, u64 addr)
{
int r = 0;
struct vgic_dist *vgic = &kvm->arch.vgic;
if (addr & ~KVM_PHYS_MASK)
return -E2BIG;
if (addr & (SZ_4K - 1))
return -EINVAL;
mutex_lock(&kvm->lock);
switch (type) {
case KVM_VGIC_V2_ADDR_TYPE_DIST:
r = vgic_ioaddr_assign(kvm, &vgic->vgic_dist_base,
addr, KVM_VGIC_V2_DIST_SIZE);
break;
case KVM_VGIC_V2_ADDR_TYPE_CPU:
r = vgic_ioaddr_assign(kvm, &vgic->vgic_cpu_base,
addr, KVM_VGIC_V2_CPU_SIZE);
break;
default:
r = -ENODEV;
}
mutex_unlock(&kvm->lock);
return r;
}