[Qemu-devel] [PATCH v4 3/8] bcm2835_ic: add bcm2835 interrupt controller

[Andrew Baumann <Andrew.Baumann@microsoft.com>]

Reviewed-by: Peter Crosthwaite <crosthwaite.peter@gmail.com>
Signed-off-by: Andrew Baumann <Andrew.Baumann@microsoft.com>
---

Notes:
    v3:
     * minor style tweaks
     * use extract32 in place of manual shift/masking
    
    v2:
     * split inputs to named gpu_irq and arm_irq gpio inputs
     * use 64-bit gpu_irq and 8-bit arm_irq status rather than 3*32-bit bitfields
     * added defined names for register offsets
     * deleted nop realize method
     * other misc cleanup suggested in review

 hw/intc/Makefile.objs        |   1 +
 hw/intc/bcm2835_ic.c         | 236 +++++++++++++++++++++++++++++++++++++++++++
 include/hw/intc/bcm2835_ic.h |  33 ++++++
 3 files changed, 270 insertions(+)
 create mode 100644 hw/intc/bcm2835_ic.c
 create mode 100644 include/hw/intc/bcm2835_ic.h

diff --git a/hw/intc/Makefile.objs b/hw/intc/Makefile.objs
index 004b0c2..2ad1204 100644
--- a/hw/intc/Makefile.objs
+++ b/hw/intc/Makefile.objs
@@ -24,6 +24,7 @@ obj-$(CONFIG_GRLIB) += grlib_irqmp.o
 obj-$(CONFIG_IOAPIC) += ioapic.o
 obj-$(CONFIG_OMAP) += omap_intc.o
 obj-$(CONFIG_OPENPIC_KVM) += openpic_kvm.o
+obj-$(CONFIG_RASPI) += bcm2835_ic.o
 obj-$(CONFIG_SH4) += sh_intc.o
 obj-$(CONFIG_XICS) += xics.o
 obj-$(CONFIG_XICS_KVM) += xics_kvm.o
diff --git a/hw/intc/bcm2835_ic.c b/hw/intc/bcm2835_ic.c
new file mode 100644
index 0000000..005a72b
--- /dev/null
+++ b/hw/intc/bcm2835_ic.c
@@ -0,0 +1,236 @@
+/*
+ * Raspberry Pi emulation (c) 2012 Gregory Estrade
+ * Refactoring for Pi2 Copyright (c) 2015, Microsoft. Written by Andrew Baumann.
+ * This code is licensed under the GNU GPLv2 and later.
+ * Heavily based on pl190.c, copyright terms below:
+ *
+ * Arm PrimeCell PL190 Vector Interrupt Controller
+ *
+ * Copyright (c) 2006 CodeSourcery.
+ * Written by Paul Brook
+ *
+ * This code is licensed under the GPL.
+ */
+
+#include "hw/intc/bcm2835_ic.h"
+
+#define GPU_IRQS 64
+#define ARM_IRQS 8
+
+#define IRQ_PENDING_BASIC       0x00 /* IRQ basic pending */
+#define IRQ_PENDING_1           0x04 /* IRQ pending 1 */
+#define IRQ_PENDING_2           0x08 /* IRQ pending 2 */
+#define FIQ_CONTROL             0x0C /* FIQ register */
+#define IRQ_ENABLE_1            0x10 /* Interrupt enable register 1 */
+#define IRQ_ENABLE_2            0x14 /* Interrupt enable register 2 */
+#define IRQ_ENABLE_BASIC        0x18 /* Base interrupt enable register */
+#define IRQ_DISABLE_1           0x1C /* Interrupt disable register 1 */
+#define IRQ_DISABLE_2           0x20 /* Interrupt disable register 2 */
+#define IRQ_DISABLE_BASIC       0x24 /* Base interrupt disable register */
+
+/* Update interrupts.  */
+static void bcm2835_ic_update(BCM2835ICState *s)
+{
+    bool set = false;
+
+    if (s->fiq_enable) {
+        if (s->fiq_select >= GPU_IRQS) {
+            /* ARM IRQ */
+            set = extract32(s->arm_irq_level, s->fiq_select - GPU_IRQS, 1);
+        } else {
+            set = extract64(s->gpu_irq_level, s->fiq_select, 1);
+        }
+    }
+    qemu_set_irq(s->fiq, set);
+
+    set = (s->gpu_irq_level & s->gpu_irq_enable)
+        || (s->arm_irq_level & s->arm_irq_enable);
+    qemu_set_irq(s->irq, set);
+
+}
+
+static void bcm2835_ic_set_gpu_irq(void *opaque, int irq, int level)
+{
+    BCM2835ICState *s = opaque;
+
+    assert(irq >= 0 && irq < 64);
+    s->gpu_irq_level = deposit64(s->gpu_irq_level, irq, 1, level != 0);
+    bcm2835_ic_update(s);
+}
+
+static void bcm2835_ic_set_arm_irq(void *opaque, int irq, int level)
+{
+    BCM2835ICState *s = opaque;
+
+    assert(irq >= 0 && irq < 8);
+    s->arm_irq_level = deposit32(s->arm_irq_level, irq, 1, level != 0);
+    bcm2835_ic_update(s);
+}
+
+static const int irq_dups[] = { 7, 9, 10, 18, 19, 53, 54, 55, 56, 57, 62 };
+
+static uint64_t bcm2835_ic_read(void *opaque, hwaddr offset, unsigned size)
+{
+    BCM2835ICState *s = opaque;
+    uint32_t res = 0;
+    uint64_t gpu_pending = s->gpu_irq_level & s->gpu_irq_enable;
+    int i;
+
+    switch (offset) {
+    case IRQ_PENDING_BASIC:
+        /* bits 0-7: ARM irqs */
+        res = s->arm_irq_level & s->arm_irq_enable;
+
+        /* bits 8 & 9: pending registers 1 & 2 */
+        res |= (((uint32_t)gpu_pending) != 0) << 8;
+        res |= ((gpu_pending >> 32) != 0) << 9;
+
+        /* bits 10-20: selected GPU IRQs */
+        for (i = 0; i < ARRAY_SIZE(irq_dups); i++) {
+            res |= extract64(gpu_pending, irq_dups[i], 1) << (i + 10);
+        }
+        break;
+    case IRQ_PENDING_1:
+        res = gpu_pending;
+        break;
+    case IRQ_PENDING_2:
+        res = gpu_pending >> 32;
+        break;
+    case FIQ_CONTROL:
+        res = (s->fiq_enable << 7) | s->fiq_select;
+        break;
+    case IRQ_ENABLE_1:
+        res = s->gpu_irq_enable;
+        break;
+    case IRQ_ENABLE_2:
+        res = s->gpu_irq_enable >> 32;
+        break;
+    case IRQ_ENABLE_BASIC:
+        res = s->arm_irq_enable;
+        break;
+    case IRQ_DISABLE_1:
+        res = ~s->gpu_irq_enable;
+        break;
+    case IRQ_DISABLE_2:
+        res = ~s->gpu_irq_enable >> 32;
+        break;
+    case IRQ_DISABLE_BASIC:
+        res = ~s->arm_irq_enable;
+        break;
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
+                      __func__, offset);
+        return 0;
+    }
+
+    return res;
+}
+
+static void bcm2835_ic_write(void *opaque, hwaddr offset, uint64_t val,
+                             unsigned size)
+{
+    BCM2835ICState *s = opaque;
+
+    switch (offset) {
+    case FIQ_CONTROL:
+        s->fiq_select = extract32(val, 0, 7);
+        s->fiq_enable = extract32(val, 7, 1);
+        break;
+    case IRQ_ENABLE_1:
+        s->gpu_irq_enable |= val;
+        break;
+    case IRQ_ENABLE_2:
+        s->gpu_irq_enable |= val << 32;
+        break;
+    case IRQ_ENABLE_BASIC:
+        s->arm_irq_enable |= val & 0xff;
+        break;
+    case IRQ_DISABLE_1:
+        s->gpu_irq_enable &= ~val;
+        break;
+    case IRQ_DISABLE_2:
+        s->gpu_irq_enable &= ~(val << 32);
+        break;
+    case IRQ_DISABLE_BASIC:
+        s->arm_irq_enable &= ~val & 0xff;
+        break;
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
+                      __func__, offset);
+        return;
+    }
+    bcm2835_ic_update(s);
+}
+
+static const MemoryRegionOps bcm2835_ic_ops = {
+    .read = bcm2835_ic_read,
+    .write = bcm2835_ic_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+    .valid.min_access_size = 4,
+    .valid.max_access_size = 4,
+};
+
+static void bcm2835_ic_reset(DeviceState *d)
+{
+    BCM2835ICState *s = BCM2835_IC(d);
+
+    s->gpu_irq_enable = 0;
+    s->arm_irq_enable = 0;
+    s->fiq_enable = false;
+    s->fiq_select = 0;
+}
+
+static void bcm2835_ic_init(Object *obj)
+{
+    BCM2835ICState *s = BCM2835_IC(obj);
+
+    memory_region_init_io(&s->iomem, obj, &bcm2835_ic_ops, s, TYPE_BCM2835_IC,
+                          0x200);
+    sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem);
+
+    qdev_init_gpio_in_named(DEVICE(s), bcm2835_ic_set_gpu_irq,
+                            BCM2835_IC_GPU_IRQ, GPU_IRQS);
+    qdev_init_gpio_in_named(DEVICE(s), bcm2835_ic_set_arm_irq,
+                            BCM2835_IC_ARM_IRQ, ARM_IRQS);
+
+    sysbus_init_irq(SYS_BUS_DEVICE(s), &s->irq);
+    sysbus_init_irq(SYS_BUS_DEVICE(s), &s->fiq);
+}
+
+static const VMStateDescription vmstate_bcm2835_ic = {
+    .name = TYPE_BCM2835_IC,
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT64(gpu_irq_level, BCM2835ICState),
+        VMSTATE_UINT64(gpu_irq_enable, BCM2835ICState),
+        VMSTATE_UINT8(arm_irq_level, BCM2835ICState),
+        VMSTATE_UINT8(arm_irq_enable, BCM2835ICState),
+        VMSTATE_BOOL(fiq_enable, BCM2835ICState),
+        VMSTATE_UINT8(fiq_select, BCM2835ICState),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static void bcm2835_ic_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->reset = bcm2835_ic_reset;
+    dc->vmsd = &vmstate_bcm2835_ic;
+}
+
+static TypeInfo bcm2835_ic_info = {
+    .name          = TYPE_BCM2835_IC,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(BCM2835ICState),
+    .class_init    = bcm2835_ic_class_init,
+    .instance_init = bcm2835_ic_init,
+};
+
+static void bcm2835_ic_register_types(void)
+{
+    type_register_static(&bcm2835_ic_info);
+}
+
+type_init(bcm2835_ic_register_types)
diff --git a/include/hw/intc/bcm2835_ic.h b/include/hw/intc/bcm2835_ic.h
new file mode 100644
index 0000000..fb75fa0
--- /dev/null
+++ b/include/hw/intc/bcm2835_ic.h
@@ -0,0 +1,33 @@
+/*
+ * Raspberry Pi emulation (c) 2012 Gregory Estrade
+ * This code is licensed under the GNU GPLv2 and later.
+ */
+
+#ifndef BCM2835_IC_H
+#define BCM2835_IC_H
+
+#include "hw/sysbus.h"
+
+#define TYPE_BCM2835_IC "bcm2835-ic"
+#define BCM2835_IC(obj) OBJECT_CHECK(BCM2835ICState, (obj), TYPE_BCM2835_IC)
+
+#define BCM2835_IC_GPU_IRQ "gpu-irq"
+#define BCM2835_IC_ARM_IRQ "arm-irq"
+
+typedef struct BCM2835ICState {
+    /*< private >*/
+    SysBusDevice busdev;
+    /*< public >*/
+
+    MemoryRegion iomem;
+    qemu_irq irq;
+    qemu_irq fiq;
+
+    /* 64 GPU IRQs + 8 ARM IRQs = 72 total (GPU first) */
+    uint64_t gpu_irq_level, gpu_irq_enable;
+    uint8_t arm_irq_level, arm_irq_enable;
+    bool fiq_enable;
+    uint8_t fiq_select;
+} BCM2835ICState;
+
+#endif
-- 
2.5.3