[Qemu-arm] [PATCH v3 2/3] hw/intc: Add (new) ASPEED VIC device model

[Andrew Jeffery]

Implement a basic ASPEED VIC device model, enough to boot a Linux kernel
configured with aspeed_defconfig. The model implements the 'new'
(revised) register set and while the hardware exposes both the new and
legacy register sets, accesses to the legacy register set will not
be serviced (though the access will be logged).

Signed-off-by: Andrew Jeffery <address@hidden>
---
Since v2:
  * Implement all supported interrupt types and configurations
  * Implement a VMStateDescription
  * Log accesses to legacy IO space
  * Add documentation on some implementation and hardware details
  * Switch to extract64/deposit64 where possible
  * Drop int_ prefix from some struct member names
  * Fix various issues with trace-event declarations
  * Include qemu/osdep.h

 hw/intc/Makefile.objs        |   1 +
 hw/intc/aspeed_vic.c         | 335 +++++++++++++++++++++++++++++++++++++++++++
 include/hw/intc/aspeed_vic.h |  48 +++++++
 trace-events                 |   7 +
 4 files changed, 391 insertions(+)
 create mode 100644 hw/intc/aspeed_vic.c
 create mode 100644 include/hw/intc/aspeed_vic.h

diff --git a/hw/intc/Makefile.objs b/hw/intc/Makefile.objs
index 6a13a39..0e47f0f 100644
--- a/hw/intc/Makefile.objs
+++ b/hw/intc/Makefile.objs
@@ -31,3 +31,4 @@ obj-$(CONFIG_XICS_KVM) += xics_kvm.o
 obj-$(CONFIG_ALLWINNER_A10_PIC) += allwinner-a10-pic.o
 obj-$(CONFIG_S390_FLIC) += s390_flic.o
 obj-$(CONFIG_S390_FLIC_KVM) += s390_flic_kvm.o
+obj-$(CONFIG_ASPEED_SOC) += aspeed_vic.o
diff --git a/hw/intc/aspeed_vic.c b/hw/intc/aspeed_vic.c
new file mode 100644
index 0000000..8cfaa02
--- /dev/null
+++ b/hw/intc/aspeed_vic.c
@@ -0,0 +1,335 @@
+/*
+ * ASPEED Interrupt Controller (New)
+ *
+ * Andrew Jeffery <address@hidden>
+ *
+ * Copyright 2015, 2016 IBM Corp.
+ *
+ * This code is licensed under the GPL version 2 or later.  See
+ * the COPYING file in the top-level directory.
+ */
+
+/* The hardware exposes two register sets, a legacy set and a 'new' set. The
+ * model implements the 'new' register set, and logs warnings on accesses to
+ * the legacy IO space.
+ *
+ * The hardware uses 32bit registers to manage 51 IRQs, with low and high
+ * registers for each conceptual register. The device model's implementation
+ * uses 64bit data types to store both low and high register values (in the one
+ * member), but must cope with access offset values in multiples of 4 passed to
+ * the callbacks. As such the read() and write() implementations process the
+ * provided offset to understand whether the access is requesting the lower or
+ * upper 32 bits of the 64bit member.
+ *
+ * Additionally, the "Interrupt Enable", "Edge Status" and "Software Interrupt"
+ * fields have separate "enable"/"status" and "clear" registers, where set bits
+ * are written to one or the other to change state (avoiding a
+ * read-modify-write sequence).
+ */
+
+#include "qemu/osdep.h"
+#include <inttypes.h>
+#include "hw/intc/aspeed_vic.h"
+#include "qemu/bitops.h"
+#include "trace.h"
+
+#define AVIC_NEW_BASE_OFFSET 0x80
+
+#define AVIC_L_MASK 0xFFFFFFFFU
+#define AVIC_H_MASK 0x0007FFFFU
+#define AVIC_EVENT_W_MASK (0x78000ULL << 32)
+
+static void aspeed_vic_update(AspeedVICState *s)
+{
+    uint64_t new = (s->raw & s->enable);
+    uint64_t flags;
+
+    flags = new & s->select;
+    trace_aspeed_vic_update_fiq(!!flags);
+    qemu_set_irq(s->fiq, !!flags);
+
+    flags = new & ~s->select;
+    trace_aspeed_vic_update_irq(!!flags);
+    qemu_set_irq(s->irq, !!flags);
+}
+
+static void aspeed_vic_set_irq(void *opaque, int irq, int level)
+{
+    uint64_t irq_mask;
+    bool raise;
+    AspeedVICState *s = (AspeedVICState *)opaque;
+
+    if (irq > ASPEED_VIC_NR_IRQS) {
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: Out-of-range interrupt number: 
%d\n",
+                      __func__, irq);
+        return;
+    }
+
+    trace_aspeed_vic_set_irq(irq, level);
+
+    irq_mask = BIT(irq);
+    if (s->sense & irq_mask) {
+        /* level-triggered */
+        if (s->event & irq_mask) {
+            /* high-sensitive */
+            raise = level;
+        } else {
+            /* low-sensitive */
+            raise = !level;
+        }
+        s->raw = deposit64(s->raw, irq, 1, raise);
+    } else {
+        uint64_t old_level = s->level & irq_mask;
+
+        /* edge-triggered */
+        if (s->dual_edge & irq_mask) {
+            raise = (!!old_level) != (!!level);
+        } else {
+            if (s->event & irq_mask) {
+                /* rising-sensitive */
+                raise = !old_level && level;
+            } else {
+                /* falling-sensitive */
+                raise = old_level && !level;
+            }
+        }
+        if (raise) {
+            s->raw = deposit64(s->raw, irq, 1, raise);
+        }
+    }
+    s->level = deposit64(s->level, irq, 1, level);
+    aspeed_vic_update(s);
+}
+
+static uint64_t aspeed_vic_read(void *opaque, hwaddr offset, unsigned size)
+{
+    uint64_t val;
+    const bool high = !!(offset & 0x4);
+    hwaddr n_offset = (offset & ~0x4);
+    AspeedVICState *s = (AspeedVICState *)opaque;
+
+    if (offset < AVIC_NEW_BASE_OFFSET) {
+        qemu_log_mask(LOG_UNIMP, "%s: Ignoring read from legacy registers "
+                      "at 0x%" HWADDR_PRIx "[%u]\n", __func__, offset, size);
+        return 0;
+    }
+
+    n_offset -= AVIC_NEW_BASE_OFFSET;
+
+    switch (n_offset) {
+    case 0x0: /* IRQ Status */
+        val = s->raw & ~s->select & s->enable;
+        break;
+    case 0x08: /* FIQ Status */
+        val = s->raw & s->select & s->enable;
+        break;
+    case 0x10: /* Raw Interrupt Status */
+        val = s->raw;
+        break;
+    case 0x18: /* Interrupt Selection */
+        val = s->select;
+        break;
+    case 0x20: /* Interrupt Enable */
+        val = s->enable;
+        break;
+    case 0x30: /* Software Interrupt */
+        val = s->trigger;
+        break;
+    case 0x40: /* Interrupt Sensitivity */
+        val = s->sense;
+        break;
+    case 0x48: /* Interrupt Both Edge Trigger Control */
+        val = s->dual_edge;
+        break;
+    case 0x50: /* Interrupt Event */
+        val = s->event;
+        break;
+    case 0x60: /* Edge Triggered Interrupt Status */
+        val = s->raw & ~s->sense;
+        break;
+        /* Illegal */
+    case 0x28: /* Interrupt Enable Clear */
+    case 0x38: /* Software Interrupt Clear */
+    case 0x58: /* Edge Triggered Interrupt Clear */
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: Read of write-only register with offset 0x%"
+                      HWADDR_PRIx "\n", __func__, offset);
+        val = 0;
+        break;
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: Bad register at offset 0x%" HWADDR_PRIx "\n",
+                      __func__, offset);
+        val = 0;
+        break;
+    }
+    if (high) {
+        val = extract64(val, 32, 19);
+    }
+    trace_aspeed_vic_read(offset, size, val);
+    return val;
+}
+
+static void aspeed_vic_write(void *opaque, hwaddr offset, uint64_t data,
+                             unsigned size)
+{
+    const bool high = !!(offset & 0x4);
+    hwaddr n_offset = (offset & ~0x4);
+    AspeedVICState *s = (AspeedVICState *)opaque;
+
+    if (offset < AVIC_NEW_BASE_OFFSET) {
+        qemu_log_mask(LOG_UNIMP,
+                      "%s: Ignoring write to legacy registers at 0x%"
+                      HWADDR_PRIx "[%u] <- 0x%" PRIx64 "\n", __func__, offset,
+                      size, data);
+        return;
+    }
+
+    n_offset -= AVIC_NEW_BASE_OFFSET;
+    trace_aspeed_vic_write(offset, size, data);
+
+    /* Given we have members using separate enable/clear registers, deposit64()
+     * isn't quite the tool for the job. Instead, relocate the incoming bits to
+     * the required bit offset based on the provided access address
+     */
+    if (high) {
+        data &= AVIC_H_MASK;
+        data <<= 32;
+    } else {
+        data &= AVIC_L_MASK;
+    }
+
+    switch (n_offset) {
+    case 0x18: /* Interrupt Selection */
+        /* Register has deposit64() semantics - overwrite requested 32 bits */
+        if (high) {
+            s->select &= AVIC_L_MASK;
+        } else {
+            s->select &= ((uint64_t) AVIC_H_MASK) << 32;
+        }
+        s->select |= data;
+        break;
+    case 0x20: /* Interrupt Enable */
+        s->enable |= data;
+        break;
+    case 0x28: /* Interrupt Enable Clear */
+        s->enable &= ~data;
+        break;
+    case 0x30: /* Software Interrupt */
+        qemu_log_mask(LOG_UNIMP, "%s: Software interrupts unavailable. "
+                "IRQs requested: 0x%016" PRIx64 "\n", __func__, data);
+        break;
+    case 0x38: /* Software Interrupt Clear */
+        qemu_log_mask(LOG_UNIMP, "%s: Software interrupts unavailable. "
+                "IRQs to be cleared: 0x%016" PRIx64 "\n", __func__, data);
+        break;
+    case 0x50: /* Interrupt Event */
+        /* Register has deposit64() semantics - overwrite the top four valid
+         * IRQ bits, as only the top four IRQs (GPIOs) can change their event
+         * type */
+        g_assert(high);
+        s->event &= ~AVIC_EVENT_W_MASK;
+        s->event |= (data & AVIC_EVENT_W_MASK);
+        break;
+    case 0x58: /* Edge Triggered Interrupt Clear */
+        s->raw &= ~(data & ~s->sense);
+        break;
+    case 0x00: /* IRQ Status */
+    case 0x08: /* FIQ Status */
+    case 0x10: /* Raw Interrupt Status */
+    case 0x40: /* Interrupt Sensitivity */
+    case 0x48: /* Interrupt Both Edge Trigger Control */
+    case 0x60: /* Edge Triggered Interrupt Status */
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: Write of read-only register with offset 0x%"
+                      HWADDR_PRIx "\n", __func__, offset);
+        break;
+
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: Bad register at offset 0x%" HWADDR_PRIx "\n",
+                      __func__, offset);
+        break;
+    }
+    aspeed_vic_update(s);
+}
+
+static const MemoryRegionOps aspeed_vic_ops = {
+    .read = aspeed_vic_read,
+    .write = aspeed_vic_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .valid.min_access_size = 4,
+    .valid.max_access_size = 4,
+    .valid.unaligned = false,
+};
+
+static void aspeed_vic_reset(DeviceState *dev)
+{
+    AspeedVICState *s = ASPEED_VIC(dev);
+
+    s->level = 0;
+    s->raw = 0;
+    s->select = 0;
+    s->enable = 0;
+    s->trigger = 0;
+    s->sense = 0x1F07FFF8FFFFULL;
+    s->dual_edge = 0xF800070000ULL;
+    s->event = 0x5F07FFF8FFFFULL;
+}
+
+#define AVIC_IO_REGION_SIZE 0x20000
+
+static void aspeed_vic_realize(DeviceState *dev, Error **errp)
+{
+    SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
+    AspeedVICState *s = ASPEED_VIC(dev);
+
+    memory_region_init_io(&s->iomem, OBJECT(s), &aspeed_vic_ops, s,
+                          TYPE_ASPEED_VIC, AVIC_IO_REGION_SIZE);
+
+    sysbus_init_mmio(sbd, &s->iomem);
+
+    qdev_init_gpio_in(dev, aspeed_vic_set_irq, ASPEED_VIC_NR_IRQS);
+    sysbus_init_irq(sbd, &s->irq);
+    sysbus_init_irq(sbd, &s->fiq);
+}
+
+static const VMStateDescription vmstate_aspeed_vic = {
+    .name = "aspeed.new-vic",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT64(level, AspeedVICState),
+        VMSTATE_UINT64(raw, AspeedVICState),
+        VMSTATE_UINT64(select, AspeedVICState),
+        VMSTATE_UINT64(enable, AspeedVICState),
+        VMSTATE_UINT64(trigger, AspeedVICState),
+        VMSTATE_UINT64(sense, AspeedVICState),
+        VMSTATE_UINT64(dual_edge, AspeedVICState),
+        VMSTATE_UINT64(event, AspeedVICState),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static void aspeed_vic_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    dc->realize = aspeed_vic_realize;
+    dc->reset = aspeed_vic_reset;
+    dc->desc = "ASPEED Interrupt Controller (New)";
+    dc->vmsd = &vmstate_aspeed_vic;
+}
+
+static const TypeInfo aspeed_vic_info = {
+    .name = TYPE_ASPEED_VIC,
+    .parent = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(AspeedVICState),
+    .class_init = aspeed_vic_class_init,
+};
+
+static void aspeed_vic_register_types(void)
+{
+    type_register_static(&aspeed_vic_info);
+}
+
+type_init(aspeed_vic_register_types);
diff --git a/include/hw/intc/aspeed_vic.h b/include/hw/intc/aspeed_vic.h
new file mode 100644
index 0000000..107ff17
--- /dev/null
+++ b/include/hw/intc/aspeed_vic.h
@@ -0,0 +1,48 @@
+/*
+ * ASPEED Interrupt Controller (New)
+ *
+ * Andrew Jeffery <address@hidden>
+ *
+ * Copyright 2016 IBM Corp.
+ *
+ * This code is licensed under the GPL version 2 or later.  See
+ * the COPYING file in the top-level directory.
+ *
+ * Need to add SVIC and CVIC support
+ */
+#ifndef ASPEED_VIC_H
+#define ASPEED_VIC_H
+
+#include "hw/sysbus.h"
+
+#define TYPE_ASPEED_VIC "aspeed.vic"
+#define ASPEED_VIC(obj) OBJECT_CHECK(AspeedVICState, (obj), TYPE_ASPEED_VIC)
+
+#define ASPEED_VIC_NR_IRQS 51
+
+typedef struct AspeedVICState {
+    /*< private >*/
+    SysBusDevice parent_obj;
+
+    /*< public >*/
+    MemoryRegion iomem;
+    qemu_irq irq;
+    qemu_irq fiq;
+
+    uint64_t level;
+    uint64_t raw;
+    uint64_t select;
+    uint64_t enable;
+    uint64_t trigger;
+
+    /* 0=edge, 1=level */
+    uint64_t sense;
+
+    /* 0=single-edge, 1=dual-edge */
+    uint64_t dual_edge;
+
+    /* 0=low-sensitive/falling-edge, 1=high-sensitive/rising-edge */
+    uint64_t event;
+} AspeedVICState;
+
+#endif /* ASPEED_VIC_H */
diff --git a/trace-events b/trace-events
index 856425d..eecca15 100644
--- a/trace-events
+++ b/trace-events
@@ -1895,3 +1895,10 @@ aspeed_timer_ctrl_pulse_enable(uint8_t i, bool enable) 
"Timer %" PRIu8 ": %d"
 aspeed_timer_set_ctrl2(uint32_t value) "Value: 0x%" PRIx32
 aspeed_timer_set_value(int timer, int reg, uint32_t value) "Timer %d register 
%d: 0x%" PRIx32
 aspeed_timer_read(uint64_t offset, unsigned size, uint64_t value) "From 0x%" 
PRIx64 ": of size %u: 0x%" PRIx64
+
+# hw/intc/aspeed_vic.c
+aspeed_vic_set_irq(int irq, int level) "Enabling IRQ %d: %d"
+aspeed_vic_update_fiq(int flags) "Raising FIQ %d"
+aspeed_vic_update_irq(int flags) "Raising IRQ %d"
+aspeed_vic_read(uint64_t offset, unsigned size, uint32_t value) "From 0x%" 
PRIx64 " of size %u: 0x%" PRIx32
+aspeed_vic_write(uint64_t offset, unsigned size, uint32_t data) "To 0x%" 
PRIx64 " of size %u: 0x%" PRIx32
-- 
2.5.0