qemu/hw/intc/arm_gic_kvm.c
Markus Armbruster 0175ba109e arm: Clean up fragile use of error_is_set() in realize() methods
Using error_is_set(ERRP) to find out whether a function failed is
either wrong, fragile, or unnecessarily opaque.  It's wrong when ERRP
may be null, because errors go undetected when it is.  It's fragile
when proving ERRP non-null involves a non-local argument.  Else, it's
unnecessarily opaque (see commit 84d18f0).

I guess the error_is_set(errp) in the DeviceClass realize() methods
are merely fragile right now, because I can't find a call chain that
passes a null errp argument.

Make the code more robust and more obviously correct: receive the
error in a local variable, then propagate it through the parameter.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Andreas Färber <afaerber@suse.de>
2014-05-05 19:08:49 +02:00

609 lines
18 KiB
C

/*
* ARM Generic Interrupt Controller using KVM in-kernel support
*
* Copyright (c) 2012 Linaro Limited
* Written by Peter Maydell
* Save/Restore logic added by Christoffer Dall.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
*
* 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, see <http://www.gnu.org/licenses/>.
*/
#include "hw/sysbus.h"
#include "sysemu/kvm.h"
#include "kvm_arm.h"
#include "gic_internal.h"
//#define DEBUG_GIC_KVM
#ifdef DEBUG_GIC_KVM
static const int debug_gic_kvm = 1;
#else
static const int debug_gic_kvm = 0;
#endif
#define DPRINTF(fmt, ...) do { \
if (debug_gic_kvm) { \
printf("arm_gic: " fmt , ## __VA_ARGS__); \
} \
} while (0)
#define TYPE_KVM_ARM_GIC "kvm-arm-gic"
#define KVM_ARM_GIC(obj) \
OBJECT_CHECK(GICState, (obj), TYPE_KVM_ARM_GIC)
#define KVM_ARM_GIC_CLASS(klass) \
OBJECT_CLASS_CHECK(KVMARMGICClass, (klass), TYPE_KVM_ARM_GIC)
#define KVM_ARM_GIC_GET_CLASS(obj) \
OBJECT_GET_CLASS(KVMARMGICClass, (obj), TYPE_KVM_ARM_GIC)
typedef struct KVMARMGICClass {
ARMGICCommonClass parent_class;
DeviceRealize parent_realize;
void (*parent_reset)(DeviceState *dev);
} KVMARMGICClass;
static void kvm_arm_gic_set_irq(void *opaque, int irq, int level)
{
/* Meaning of the 'irq' parameter:
* [0..N-1] : external interrupts
* [N..N+31] : PPI (internal) interrupts for CPU 0
* [N+32..N+63] : PPI (internal interrupts for CPU 1
* ...
* Convert this to the kernel's desired encoding, which
* has separate fields in the irq number for type,
* CPU number and interrupt number.
*/
GICState *s = (GICState *)opaque;
int kvm_irq, irqtype, cpu;
if (irq < (s->num_irq - GIC_INTERNAL)) {
/* External interrupt. The kernel numbers these like the GIC
* hardware, with external interrupt IDs starting after the
* internal ones.
*/
irqtype = KVM_ARM_IRQ_TYPE_SPI;
cpu = 0;
irq += GIC_INTERNAL;
} else {
/* Internal interrupt: decode into (cpu, interrupt id) */
irqtype = KVM_ARM_IRQ_TYPE_PPI;
irq -= (s->num_irq - GIC_INTERNAL);
cpu = irq / GIC_INTERNAL;
irq %= GIC_INTERNAL;
}
kvm_irq = (irqtype << KVM_ARM_IRQ_TYPE_SHIFT)
| (cpu << KVM_ARM_IRQ_VCPU_SHIFT) | irq;
kvm_set_irq(kvm_state, kvm_irq, !!level);
}
static bool kvm_arm_gic_can_save_restore(GICState *s)
{
return s->dev_fd >= 0;
}
static void kvm_gic_access(GICState *s, int group, int offset,
int cpu, uint32_t *val, bool write)
{
struct kvm_device_attr attr;
int type;
int err;
cpu = cpu & 0xff;
attr.flags = 0;
attr.group = group;
attr.attr = (((uint64_t)cpu << KVM_DEV_ARM_VGIC_CPUID_SHIFT) &
KVM_DEV_ARM_VGIC_CPUID_MASK) |
(((uint64_t)offset << KVM_DEV_ARM_VGIC_OFFSET_SHIFT) &
KVM_DEV_ARM_VGIC_OFFSET_MASK);
attr.addr = (uintptr_t)val;
if (write) {
type = KVM_SET_DEVICE_ATTR;
} else {
type = KVM_GET_DEVICE_ATTR;
}
err = kvm_device_ioctl(s->dev_fd, type, &attr);
if (err < 0) {
fprintf(stderr, "KVM_{SET/GET}_DEVICE_ATTR failed: %s\n",
strerror(-err));
abort();
}
}
static void kvm_gicd_access(GICState *s, int offset, int cpu,
uint32_t *val, bool write)
{
kvm_gic_access(s, KVM_DEV_ARM_VGIC_GRP_DIST_REGS,
offset, cpu, val, write);
}
static void kvm_gicc_access(GICState *s, int offset, int cpu,
uint32_t *val, bool write)
{
kvm_gic_access(s, KVM_DEV_ARM_VGIC_GRP_CPU_REGS,
offset, cpu, val, write);
}
#define for_each_irq_reg(_ctr, _max_irq, _field_width) \
for (_ctr = 0; _ctr < ((_max_irq) / (32 / (_field_width))); _ctr++)
/*
* Translate from the in-kernel field for an IRQ value to/from the qemu
* representation.
*/
typedef void (*vgic_translate_fn)(GICState *s, int irq, int cpu,
uint32_t *field, bool to_kernel);
/* synthetic translate function used for clear/set registers to completely
* clear a setting using a clear-register before setting the remaining bits
* using a set-register */
static void translate_clear(GICState *s, int irq, int cpu,
uint32_t *field, bool to_kernel)
{
if (to_kernel) {
*field = ~0;
} else {
/* does not make sense: qemu model doesn't use set/clear regs */
abort();
}
}
static void translate_enabled(GICState *s, int irq, int cpu,
uint32_t *field, bool to_kernel)
{
int cm = (irq < GIC_INTERNAL) ? (1 << cpu) : ALL_CPU_MASK;
if (to_kernel) {
*field = GIC_TEST_ENABLED(irq, cm);
} else {
if (*field & 1) {
GIC_SET_ENABLED(irq, cm);
}
}
}
static void translate_pending(GICState *s, int irq, int cpu,
uint32_t *field, bool to_kernel)
{
int cm = (irq < GIC_INTERNAL) ? (1 << cpu) : ALL_CPU_MASK;
if (to_kernel) {
*field = gic_test_pending(s, irq, cm);
} else {
if (*field & 1) {
GIC_SET_PENDING(irq, cm);
/* TODO: Capture is level-line is held high in the kernel */
}
}
}
static void translate_active(GICState *s, int irq, int cpu,
uint32_t *field, bool to_kernel)
{
int cm = (irq < GIC_INTERNAL) ? (1 << cpu) : ALL_CPU_MASK;
if (to_kernel) {
*field = GIC_TEST_ACTIVE(irq, cm);
} else {
if (*field & 1) {
GIC_SET_ACTIVE(irq, cm);
}
}
}
static void translate_trigger(GICState *s, int irq, int cpu,
uint32_t *field, bool to_kernel)
{
if (to_kernel) {
*field = (GIC_TEST_EDGE_TRIGGER(irq)) ? 0x2 : 0x0;
} else {
if (*field & 0x2) {
GIC_SET_EDGE_TRIGGER(irq);
}
}
}
static void translate_priority(GICState *s, int irq, int cpu,
uint32_t *field, bool to_kernel)
{
if (to_kernel) {
*field = GIC_GET_PRIORITY(irq, cpu) & 0xff;
} else {
gic_set_priority(s, cpu, irq, *field & 0xff);
}
}
static void translate_targets(GICState *s, int irq, int cpu,
uint32_t *field, bool to_kernel)
{
if (to_kernel) {
*field = s->irq_target[irq] & 0xff;
} else {
s->irq_target[irq] = *field & 0xff;
}
}
static void translate_sgisource(GICState *s, int irq, int cpu,
uint32_t *field, bool to_kernel)
{
if (to_kernel) {
*field = s->sgi_pending[irq][cpu] & 0xff;
} else {
s->sgi_pending[irq][cpu] = *field & 0xff;
}
}
/* Read a register group from the kernel VGIC */
static void kvm_dist_get(GICState *s, uint32_t offset, int width,
int maxirq, vgic_translate_fn translate_fn)
{
uint32_t reg;
int i;
int j;
int irq;
int cpu;
int regsz = 32 / width; /* irqs per kernel register */
uint32_t field;
for_each_irq_reg(i, maxirq, width) {
irq = i * regsz;
cpu = 0;
while ((cpu < s->num_cpu && irq < GIC_INTERNAL) || cpu == 0) {
kvm_gicd_access(s, offset, cpu, &reg, false);
for (j = 0; j < regsz; j++) {
field = extract32(reg, j * width, width);
translate_fn(s, irq + j, cpu, &field, false);
}
cpu++;
}
offset += 4;
}
}
/* Write a register group to the kernel VGIC */
static void kvm_dist_put(GICState *s, uint32_t offset, int width,
int maxirq, vgic_translate_fn translate_fn)
{
uint32_t reg;
int i;
int j;
int irq;
int cpu;
int regsz = 32 / width; /* irqs per kernel register */
uint32_t field;
for_each_irq_reg(i, maxirq, width) {
irq = i * regsz;
cpu = 0;
while ((cpu < s->num_cpu && irq < GIC_INTERNAL) || cpu == 0) {
reg = 0;
for (j = 0; j < regsz; j++) {
translate_fn(s, irq + j, cpu, &field, true);
reg = deposit32(reg, j * width, width, field);
}
kvm_gicd_access(s, offset, cpu, &reg, true);
cpu++;
}
offset += 4;
}
}
static void kvm_arm_gic_put(GICState *s)
{
uint32_t reg;
int i;
int cpu;
int num_cpu;
int num_irq;
if (!kvm_arm_gic_can_save_restore(s)) {
DPRINTF("Cannot put kernel gic state, no kernel interface");
return;
}
/* Note: We do the restore in a slightly different order than the save
* (where the order doesn't matter and is simply ordered according to the
* register offset values */
/*****************************************************************
* Distributor State
*/
/* s->enabled -> GICD_CTLR */
reg = s->enabled;
kvm_gicd_access(s, 0x0, 0, &reg, true);
/* Sanity checking on GICD_TYPER and s->num_irq, s->num_cpu */
kvm_gicd_access(s, 0x4, 0, &reg, false);
num_irq = ((reg & 0x1f) + 1) * 32;
num_cpu = ((reg & 0xe0) >> 5) + 1;
if (num_irq < s->num_irq) {
fprintf(stderr, "Restoring %u IRQs, but kernel supports max %d\n",
s->num_irq, num_irq);
abort();
} else if (num_cpu != s->num_cpu) {
fprintf(stderr, "Restoring %u CPU interfaces, kernel only has %d\n",
s->num_cpu, num_cpu);
/* Did we not create the VCPUs in the kernel yet? */
abort();
}
/* TODO: Consider checking compatibility with the IIDR ? */
/* irq_state[n].enabled -> GICD_ISENABLERn */
kvm_dist_put(s, 0x180, 1, s->num_irq, translate_clear);
kvm_dist_put(s, 0x100, 1, s->num_irq, translate_enabled);
/* s->irq_target[irq] -> GICD_ITARGETSRn
* (restore targets before pending to ensure the pending state is set on
* the appropriate CPU interfaces in the kernel) */
kvm_dist_put(s, 0x800, 8, s->num_irq, translate_targets);
/* irq_state[n].pending + irq_state[n].level -> GICD_ISPENDRn */
kvm_dist_put(s, 0x280, 1, s->num_irq, translate_clear);
kvm_dist_put(s, 0x200, 1, s->num_irq, translate_pending);
/* irq_state[n].active -> GICD_ISACTIVERn */
kvm_dist_put(s, 0x380, 1, s->num_irq, translate_clear);
kvm_dist_put(s, 0x300, 1, s->num_irq, translate_active);
/* irq_state[n].trigger -> GICD_ICFRn */
kvm_dist_put(s, 0xc00, 2, s->num_irq, translate_trigger);
/* s->priorityX[irq] -> ICD_IPRIORITYRn */
kvm_dist_put(s, 0x400, 8, s->num_irq, translate_priority);
/* s->sgi_pending -> ICD_CPENDSGIRn */
kvm_dist_put(s, 0xf10, 8, GIC_NR_SGIS, translate_clear);
kvm_dist_put(s, 0xf20, 8, GIC_NR_SGIS, translate_sgisource);
/*****************************************************************
* CPU Interface(s) State
*/
for (cpu = 0; cpu < s->num_cpu; cpu++) {
/* s->cpu_enabled[cpu] -> GICC_CTLR */
reg = s->cpu_enabled[cpu];
kvm_gicc_access(s, 0x00, cpu, &reg, true);
/* s->priority_mask[cpu] -> GICC_PMR */
reg = (s->priority_mask[cpu] & 0xff);
kvm_gicc_access(s, 0x04, cpu, &reg, true);
/* s->bpr[cpu] -> GICC_BPR */
reg = (s->bpr[cpu] & 0x7);
kvm_gicc_access(s, 0x08, cpu, &reg, true);
/* s->abpr[cpu] -> GICC_ABPR */
reg = (s->abpr[cpu] & 0x7);
kvm_gicc_access(s, 0x1c, cpu, &reg, true);
/* s->apr[n][cpu] -> GICC_APRn */
for (i = 0; i < 4; i++) {
reg = s->apr[i][cpu];
kvm_gicc_access(s, 0xd0 + i * 4, cpu, &reg, true);
}
}
}
static void kvm_arm_gic_get(GICState *s)
{
uint32_t reg;
int i;
int cpu;
if (!kvm_arm_gic_can_save_restore(s)) {
DPRINTF("Cannot get kernel gic state, no kernel interface");
return;
}
/*****************************************************************
* Distributor State
*/
/* GICD_CTLR -> s->enabled */
kvm_gicd_access(s, 0x0, 0, &reg, false);
s->enabled = reg & 1;
/* Sanity checking on GICD_TYPER -> s->num_irq, s->num_cpu */
kvm_gicd_access(s, 0x4, 0, &reg, false);
s->num_irq = ((reg & 0x1f) + 1) * 32;
s->num_cpu = ((reg & 0xe0) >> 5) + 1;
if (s->num_irq > GIC_MAXIRQ) {
fprintf(stderr, "Too many IRQs reported from the kernel: %d\n",
s->num_irq);
abort();
}
/* GICD_IIDR -> ? */
kvm_gicd_access(s, 0x8, 0, &reg, false);
/* Verify no GROUP 1 interrupts configured in the kernel */
for_each_irq_reg(i, s->num_irq, 1) {
kvm_gicd_access(s, 0x80 + (i * 4), 0, &reg, false);
if (reg != 0) {
fprintf(stderr, "Unsupported GICD_IGROUPRn value: %08x\n",
reg);
abort();
}
}
/* Clear all the IRQ settings */
for (i = 0; i < s->num_irq; i++) {
memset(&s->irq_state[i], 0, sizeof(s->irq_state[0]));
}
/* GICD_ISENABLERn -> irq_state[n].enabled */
kvm_dist_get(s, 0x100, 1, s->num_irq, translate_enabled);
/* GICD_ISPENDRn -> irq_state[n].pending + irq_state[n].level */
kvm_dist_get(s, 0x200, 1, s->num_irq, translate_pending);
/* GICD_ISACTIVERn -> irq_state[n].active */
kvm_dist_get(s, 0x300, 1, s->num_irq, translate_active);
/* GICD_ICFRn -> irq_state[n].trigger */
kvm_dist_get(s, 0xc00, 2, s->num_irq, translate_trigger);
/* GICD_IPRIORITYRn -> s->priorityX[irq] */
kvm_dist_get(s, 0x400, 8, s->num_irq, translate_priority);
/* GICD_ITARGETSRn -> s->irq_target[irq] */
kvm_dist_get(s, 0x800, 8, s->num_irq, translate_targets);
/* GICD_CPENDSGIRn -> s->sgi_pending */
kvm_dist_get(s, 0xf10, 8, GIC_NR_SGIS, translate_sgisource);
/*****************************************************************
* CPU Interface(s) State
*/
for (cpu = 0; cpu < s->num_cpu; cpu++) {
/* GICC_CTLR -> s->cpu_enabled[cpu] */
kvm_gicc_access(s, 0x00, cpu, &reg, false);
s->cpu_enabled[cpu] = (reg & 1);
/* GICC_PMR -> s->priority_mask[cpu] */
kvm_gicc_access(s, 0x04, cpu, &reg, false);
s->priority_mask[cpu] = (reg & 0xff);
/* GICC_BPR -> s->bpr[cpu] */
kvm_gicc_access(s, 0x08, cpu, &reg, false);
s->bpr[cpu] = (reg & 0x7);
/* GICC_ABPR -> s->abpr[cpu] */
kvm_gicc_access(s, 0x1c, cpu, &reg, false);
s->abpr[cpu] = (reg & 0x7);
/* GICC_APRn -> s->apr[n][cpu] */
for (i = 0; i < 4; i++) {
kvm_gicc_access(s, 0xd0 + i * 4, cpu, &reg, false);
s->apr[i][cpu] = reg;
}
}
}
static void kvm_arm_gic_reset(DeviceState *dev)
{
GICState *s = ARM_GIC_COMMON(dev);
KVMARMGICClass *kgc = KVM_ARM_GIC_GET_CLASS(s);
kgc->parent_reset(dev);
kvm_arm_gic_put(s);
}
static void kvm_arm_gic_realize(DeviceState *dev, Error **errp)
{
int i;
GICState *s = KVM_ARM_GIC(dev);
SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
KVMARMGICClass *kgc = KVM_ARM_GIC_GET_CLASS(s);
Error *local_err = NULL;
int ret;
kgc->parent_realize(dev, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
i = s->num_irq - GIC_INTERNAL;
/* For the GIC, also expose incoming GPIO lines for PPIs for each CPU.
* GPIO array layout is thus:
* [0..N-1] SPIs
* [N..N+31] PPIs for CPU 0
* [N+32..N+63] PPIs for CPU 1
* ...
*/
i += (GIC_INTERNAL * s->num_cpu);
qdev_init_gpio_in(dev, kvm_arm_gic_set_irq, i);
/* We never use our outbound IRQ lines but provide them so that
* we maintain the same interface as the non-KVM GIC.
*/
for (i = 0; i < s->num_cpu; i++) {
sysbus_init_irq(sbd, &s->parent_irq[i]);
}
/* Try to create the device via the device control API */
s->dev_fd = -1;
ret = kvm_create_device(kvm_state, KVM_DEV_TYPE_ARM_VGIC_V2, false);
if (ret >= 0) {
s->dev_fd = ret;
} else if (ret != -ENODEV && ret != -ENOTSUP) {
error_setg_errno(errp, -ret, "error creating in-kernel VGIC");
return;
}
/* Distributor */
memory_region_init_reservation(&s->iomem, OBJECT(s),
"kvm-gic_dist", 0x1000);
sysbus_init_mmio(sbd, &s->iomem);
kvm_arm_register_device(&s->iomem,
(KVM_ARM_DEVICE_VGIC_V2 << KVM_ARM_DEVICE_ID_SHIFT)
| KVM_VGIC_V2_ADDR_TYPE_DIST,
KVM_DEV_ARM_VGIC_GRP_ADDR,
KVM_VGIC_V2_ADDR_TYPE_DIST,
s->dev_fd);
/* CPU interface for current core. Unlike arm_gic, we don't
* provide the "interface for core #N" memory regions, because
* cores with a VGIC don't have those.
*/
memory_region_init_reservation(&s->cpuiomem[0], OBJECT(s),
"kvm-gic_cpu", 0x1000);
sysbus_init_mmio(sbd, &s->cpuiomem[0]);
kvm_arm_register_device(&s->cpuiomem[0],
(KVM_ARM_DEVICE_VGIC_V2 << KVM_ARM_DEVICE_ID_SHIFT)
| KVM_VGIC_V2_ADDR_TYPE_CPU,
KVM_DEV_ARM_VGIC_GRP_ADDR,
KVM_VGIC_V2_ADDR_TYPE_CPU,
s->dev_fd);
}
static void kvm_arm_gic_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
ARMGICCommonClass *agcc = ARM_GIC_COMMON_CLASS(klass);
KVMARMGICClass *kgc = KVM_ARM_GIC_CLASS(klass);
agcc->pre_save = kvm_arm_gic_get;
agcc->post_load = kvm_arm_gic_put;
kgc->parent_realize = dc->realize;
kgc->parent_reset = dc->reset;
dc->realize = kvm_arm_gic_realize;
dc->reset = kvm_arm_gic_reset;
}
static const TypeInfo kvm_arm_gic_info = {
.name = TYPE_KVM_ARM_GIC,
.parent = TYPE_ARM_GIC_COMMON,
.instance_size = sizeof(GICState),
.class_init = kvm_arm_gic_class_init,
.class_size = sizeof(KVMARMGICClass),
};
static void kvm_arm_gic_register_types(void)
{
type_register_static(&kvm_arm_gic_info);
}
type_init(kvm_arm_gic_register_types)