hw/intc: add goldfish-pic

Implement the goldfish pic device as defined in

https://android.googlesource.com/platform/external/qemu/+/master/docs/GOLDFISH-VIRTUAL-HARDWARE.TXT

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20210312214145.2936082-3-laurent@vivier.eu>

5 files changed, 264 insertions, 0 deletions

diff --git a/hw/intc/Kconfig b/hw/intc/Kconfig
index 66bf0b90b4..186cb5daa0 100644
--- a/hw/intc/Kconfig
+++ b/hw/intc/Kconfig
@@ -67,3 +67,6 @@ config SIFIVE_CLINT
 
 config SIFIVE_PLIC
     bool
+
+config GOLDFISH_PIC
+    bool
diff --git a/hw/intc/goldfish_pic.c b/hw/intc/goldfish_pic.c
new file mode 100644
index 0000000000..e3b43a69f1
--- /dev/null
+++ b/hw/intc/goldfish_pic.c
@@ -0,0 +1,219 @@
+/*
+ * SPDX-License-Identifer: GPL-2.0-or-later
+ *
+ * Goldfish PIC
+ *
+ * (c) 2020 Laurent Vivier <laurent@vivier.eu>
+ *
+ */
+
+#include "qemu/osdep.h"
+#include "hw/irq.h"
+#include "hw/qdev-properties.h"
+#include "hw/sysbus.h"
+#include "migration/vmstate.h"
+#include "monitor/monitor.h"
+#include "qemu/log.h"
+#include "trace.h"
+#include "hw/intc/intc.h"
+#include "hw/intc/goldfish_pic.h"
+
+/* registers */
+
+enum {
+    REG_STATUS          = 0x00,
+    REG_IRQ_PENDING     = 0x04,
+    REG_IRQ_DISABLE_ALL = 0x08,
+    REG_DISABLE         = 0x0c,
+    REG_ENABLE          = 0x10,
+};
+
+static bool goldfish_pic_get_statistics(InterruptStatsProvider *obj,
+                                        uint64_t **irq_counts,
+                                        unsigned int *nb_irqs)
+{
+    GoldfishPICState *s = GOLDFISH_PIC(obj);
+
+    *irq_counts = s->stats_irq_count;
+    *nb_irqs = ARRAY_SIZE(s->stats_irq_count);
+    return true;
+}
+
+static void goldfish_pic_print_info(InterruptStatsProvider *obj, Monitor *mon)
+{
+    GoldfishPICState *s = GOLDFISH_PIC(obj);
+    monitor_printf(mon, "goldfish-pic.%d: pending=0x%08x enabled=0x%08x\n",
+                   s->idx, s->pending, s->enabled);
+}
+
+static void goldfish_pic_update(GoldfishPICState *s)
+{
+    if (s->pending & s->enabled) {
+        qemu_irq_raise(s->irq);
+    } else {
+        qemu_irq_lower(s->irq);
+    }
+}
+
+static void goldfish_irq_request(void *opaque, int irq, int level)
+{
+    GoldfishPICState *s = opaque;
+
+    trace_goldfish_irq_request(s, s->idx, irq, level);
+
+    if (level) {
+        s->pending |= 1 << irq;
+        s->stats_irq_count[irq]++;
+    } else {
+        s->pending &= ~(1 << irq);
+    }
+    goldfish_pic_update(s);
+}
+
+static uint64_t goldfish_pic_read(void *opaque, hwaddr addr,
+                                  unsigned size)
+{
+    GoldfishPICState *s = opaque;
+    uint64_t value = 0;
+
+    switch (addr) {
+    case REG_STATUS:
+        /* The number of pending interrupts (0 to 32) */
+        value = ctpop32(s->pending & s->enabled);
+        break;
+    case REG_IRQ_PENDING:
+        /* The pending interrupt mask */
+        value = s->pending & s->enabled;
+        break;
+    default:
+        qemu_log_mask(LOG_UNIMP,
+                      "%s: unimplemented register read 0x%02"HWADDR_PRIx"\n",
+                      __func__, addr);
+        break;
+    }
+
+    trace_goldfish_pic_read(s, s->idx, addr, size, value);
+
+    return value;
+}
+
+static void goldfish_pic_write(void *opaque, hwaddr addr,
+                               uint64_t value, unsigned size)
+{
+    GoldfishPICState *s = opaque;
+
+    trace_goldfish_pic_write(s, s->idx, addr, size, value);
+
+    switch (addr) {
+    case REG_IRQ_DISABLE_ALL:
+        s->enabled = 0;
+        s->pending = 0;
+        break;
+    case REG_DISABLE:
+        s->enabled &= ~value;
+        break;
+    case REG_ENABLE:
+        s->enabled |= value;
+        break;
+    default:
+        qemu_log_mask(LOG_UNIMP,
+                      "%s: unimplemented register write 0x%02"HWADDR_PRIx"\n",
+                      __func__, addr);
+        break;
+    }
+    goldfish_pic_update(s);
+}
+
+static const MemoryRegionOps goldfish_pic_ops = {
+    .read = goldfish_pic_read,
+    .write = goldfish_pic_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+    .valid.max_access_size = 4,
+    .impl.min_access_size = 4,
+    .impl.max_access_size = 4,
+};
+
+static void goldfish_pic_reset(DeviceState *dev)
+{
+    GoldfishPICState *s = GOLDFISH_PIC(dev);
+    int i;
+
+    trace_goldfish_pic_reset(s, s->idx);
+    s->pending = 0;
+    s->enabled = 0;
+
+    for (i = 0; i < ARRAY_SIZE(s->stats_irq_count); i++) {
+        s->stats_irq_count[i] = 0;
+    }
+}
+
+static void goldfish_pic_realize(DeviceState *dev, Error **errp)
+{
+    GoldfishPICState *s = GOLDFISH_PIC(dev);
+
+    trace_goldfish_pic_realize(s, s->idx);
+
+    memory_region_init_io(&s->iomem, OBJECT(s), &goldfish_pic_ops, s,
+                          "goldfish_pic", 0x24);
+}
+
+static const VMStateDescription vmstate_goldfish_pic = {
+    .name = "goldfish_pic",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32(pending, GoldfishPICState),
+        VMSTATE_UINT32(enabled, GoldfishPICState),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static void goldfish_pic_instance_init(Object *obj)
+{
+    SysBusDevice *dev = SYS_BUS_DEVICE(obj);
+    GoldfishPICState *s = GOLDFISH_PIC(obj);
+
+    trace_goldfish_pic_instance_init(s);
+
+    sysbus_init_mmio(dev, &s->iomem);
+    sysbus_init_irq(dev, &s->irq);
+
+    qdev_init_gpio_in(DEVICE(obj), goldfish_irq_request, GOLDFISH_PIC_IRQ_NB);
+}
+
+static Property goldfish_pic_properties[] = {
+    DEFINE_PROP_UINT8("index", GoldfishPICState, idx, 0),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void goldfish_pic_class_init(ObjectClass *oc, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(oc);
+    InterruptStatsProviderClass *ic = INTERRUPT_STATS_PROVIDER_CLASS(oc);
+
+    dc->reset = goldfish_pic_reset;
+    dc->realize = goldfish_pic_realize;
+    dc->vmsd = &vmstate_goldfish_pic;
+    ic->get_statistics = goldfish_pic_get_statistics;
+    ic->print_info = goldfish_pic_print_info;
+    device_class_set_props(dc, goldfish_pic_properties);
+}
+
+static const TypeInfo goldfish_pic_info = {
+    .name = TYPE_GOLDFISH_PIC,
+    .parent = TYPE_SYS_BUS_DEVICE,
+    .class_init = goldfish_pic_class_init,
+    .instance_init = goldfish_pic_instance_init,
+    .instance_size = sizeof(GoldfishPICState),
+    .interfaces = (InterfaceInfo[]) {
+         { TYPE_INTERRUPT_STATS_PROVIDER },
+         { }
+    },
+};
+
+static void goldfish_pic_register_types(void)
+{
+    type_register_static(&goldfish_pic_info);
+}
+
+type_init(goldfish_pic_register_types)
diff --git a/hw/intc/meson.build b/hw/intc/meson.build
index 8df3656419..5fcb923dd1 100644
--- a/hw/intc/meson.build
+++ b/hw/intc/meson.build
@@ -57,3 +57,4 @@ specific_ss.add(when: 'CONFIG_PSERIES', if_true: files('xics_spapr.c', 'spapr_xi
 specific_ss.add(when: 'CONFIG_XIVE', if_true: files('xive.c'))
 specific_ss.add(when: ['CONFIG_KVM', 'CONFIG_XIVE'],
 		if_true: files('spapr_xive_kvm.c'))
+specific_ss.add(when: 'CONFIG_GOLDFISH_PIC', if_true: files('goldfish_pic.c'))
diff --git a/hw/intc/trace-events b/hw/intc/trace-events
index 45ddaf48df..c9ab17234b 100644
--- a/hw/intc/trace-events
+++ b/hw/intc/trace-events
@@ -239,3 +239,11 @@ xive_end_source_read(uint8_t end_blk, uint32_t end_idx, uint64_t addr) "END 0x%x
 
 # pnv_xive.c
 pnv_xive_ic_hw_trigger(uint64_t addr, uint64_t val) "@0x%"PRIx64" val=0x%"PRIx64
+
+# goldfish_pic.c
+goldfish_irq_request(void *dev, int idx, int irq, int level) "pic: %p goldfish-irq.%d irq: %d level: %d"
+goldfish_pic_read(void *dev, int idx, unsigned int addr, unsigned int size, uint64_t value) "pic: %p goldfish-irq.%d reg: 0x%02x size: %d value: 0x%"PRIx64
+goldfish_pic_write(void *dev, int idx, unsigned int addr, unsigned int size, uint64_t value) "pic: %p goldfish-irq.%d reg: 0x%02x size: %d value: 0x%"PRIx64
+goldfish_pic_reset(void *dev, int idx) "pic: %p goldfish-irq.%d"
+goldfish_pic_realize(void *dev, int idx) "pic: %p goldfish-irq.%d"
+goldfish_pic_instance_init(void *dev) "pic: %p goldfish-irq"
diff --git a/include/hw/intc/goldfish_pic.h b/include/hw/intc/goldfish_pic.h
new file mode 100644
index 0000000000..ad13ab37fc
--- /dev/null
+++ b/include/hw/intc/goldfish_pic.h
@@ -0,0 +1,33 @@
+/*
+ * SPDX-License-Identifer: GPL-2.0-or-later
+ *
+ * Goldfish PIC
+ *
+ * (c) 2020 Laurent Vivier <laurent@vivier.eu>
+ *
+ */
+
+#ifndef HW_INTC_GOLDFISH_PIC_H
+#define HW_INTC_GOLDFISH_PIC_H
+
+#define TYPE_GOLDFISH_PIC "goldfish_pic"
+OBJECT_DECLARE_SIMPLE_TYPE(GoldfishPICState, GOLDFISH_PIC)
+
+#define GOLDFISH_PIC_IRQ_NB 32
+
+struct GoldfishPICState {
+    SysBusDevice parent_obj;
+
+    MemoryRegion iomem;
+    qemu_irq irq;
+
+    uint32_t pending;
+    uint32_t enabled;
+
+    /* statistics */
+    uint64_t stats_irq_count[32];
+    /* for tracing */
+    uint8_t idx;
+};
+
+#endif