Re: [Qemu-devel] [PATCH V2 3/4] imx.31 and KZM board support: interrupt controller

[Peter Chubb <peter.chubb@nicta.com.au>]

Implement the FreeSCALE i.MX31 advanced vectored interrupt controller, at least
to the extent it is used by Linux 3.0.x

Signed-off-by: Hans Jang <hsjang@ok-labs.com>
Signed-off-by: Adam Clench <adamc@ok-labs.com>
Signed-off-by: Peter Chubb <peter.chubb@nicta.com.au>
---
 hw/imx_avic.c |  363 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 363 insertions(+)
 create mode 100644 hw/imx_avic.c

Index: qemu-working/hw/imx_avic.c
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ qemu-working/hw/imx_avic.c	2011-11-22 14:47:10.706040936 +1100
@@ -0,0 +1,363 @@
+/*
+ * IMX31 Vectored Interrupt Controller
+ *
+ * Note this is NOT the PL192 provided by ARM, but
+ * a custom implementation by FreeScale.
+ *
+ * Copyright (c) 2008 OKL
+ * Written by Hans
+ *
+ * This code is licenced under the GPL version 2 or later.
+ *
+ * TODO: implement vectors and priorities.
+ */
+
+#include "hw.h"
+#include "sysbus.h"
+#include <string.h> /* ffsll */
+
+#define DEBUG_INT 1
+#undef DEBUG_INT /* comment out for debugging */
+
+#ifdef DEBUG_INT
+#define DPRINTF(fmt, args...) \
+do { printf("imx_int: " fmt , ##args); } while (0)
+#else
+#define DPRINTF(fmt, args...) do {} while (0)
+#endif
+
+/*
+ * Print a message at most ten times.
+ */
+#define scream(fmt, args...) \
+    do { \
+        static int printable = 10;\
+        if (printable--) { \
+            fprintf(stderr, fmt, ##args); \
+        } \
+    } while (0)
+
+
+#define IMX_INT_NUM_IRQS 64
+
+/* Interrupt Control Bits */
+#define ABFLAG (1<<25)
+#define ABFEN (1<<24)
+#define NIDIS (1<<22) /* Normal Interrupt disable */
+#define FIDIS (1<<21) /* Fast interrupt disable */
+#define NIAD  (1<<20) /* Normal Interrupt Arbiter Rise ARM level */
+#define FIAD  (1<<19) /* Fast Interrupt Arbiter Rise ARM level */
+#define NM    (1<<18) /* Normal interrupt mode */
+
+
+#define PRIO_PER_WORD (sizeof (uint32_t) * 8 / 4)
+#define PRIO_WORDS (IMX_INT_NUM_IRQS/PRIO_PER_WORD)
+
+typedef struct {
+    SysBusDevice busdev;
+    MemoryRegion iomem;
+    uint64_t pending;
+    uint64_t enabled;
+    uint64_t is_fiq;
+    uint32_t intcntl;
+    uint32_t intmask;
+    qemu_irq irq;
+    qemu_irq fiq;
+    uint32_t prio[PRIO_WORDS]; /* Priorities are 4-bits each */
+} imx_int_state;
+
+static const VMStateDescription vmstate_imx_avic = {
+    .name = "imx-avic",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .minimum_version_id_old = 1,
+    .fields = (VMStateField []) {
+        VMSTATE_UINT64(pending, imx_int_state),
+        VMSTATE_UINT64(enabled, imx_int_state),
+        VMSTATE_UINT64(is_fiq, imx_int_state),
+        VMSTATE_UINT32(intcntl, imx_int_state),
+        VMSTATE_UINT32(intmask, imx_int_state),
+        VMSTATE_UINT32_ARRAY(prio, imx_int_state, PRIO_WORDS),
+        VMSTATE_END_OF_LIST()
+    },
+};
+
+
+
+static inline int imx_int_prio(imx_int_state *s, int irq)
+{
+    uint32_t word = irq / PRIO_PER_WORD;
+    uint32_t part = 4 * (irq % PRIO_PER_WORD);
+    return 0xf & (s->prio[word] >> part);
+}
+
+static inline void imx_int_set_prio(imx_int_state *s, int irq, int prio)
+{
+    uint32_t word = irq / PRIO_PER_WORD;
+    uint32_t part = 4 * (irq % PRIO_PER_WORD);
+    uint32_t mask = ~(0xf << part);
+    s->prio[word] &= mask;
+    s->prio[word] |= prio << part;
+}
+
+/* Update interrupts.  */
+static void imx_int_update(imx_int_state *s)
+{
+    int i;
+    uint64_t new = s->pending;
+    uint64_t flags;
+
+    flags = new & s->enabled & s->is_fiq;
+    qemu_set_irq(s->fiq, !!flags);
+
+    flags = new & s->enabled & ~s->is_fiq;
+    if (!flags || ((s->intmask & 0x1f) == 0x1f)) {
+        qemu_set_irq(s->irq, !!flags);
+        return;
+    }
+
+    /* Take interrupt if  prio lower than the value of intmask */
+    for (i = 0; i < IMX_INT_NUM_IRQS; i++) {
+        if (flags & (1UL << i)) {
+            if (imx_int_prio(s, i) > s->intmask) {
+                qemu_set_irq(s->irq, 1);
+                return;
+            }
+        }
+    }
+
+}
+
+static void imx_int_set_irq(void *opaque, int irq, int level)
+{
+    imx_int_state *s = (imx_int_state *)opaque;
+
+    if (level) {
+        s->pending |= (1ULL << irq);
+    } else {
+        s->pending &= ~(1ULL << irq);
+    }
+
+    imx_int_update(s);
+}
+
+
+static uint64_t imx_int_read(void *opaque,
+                             target_phys_addr_t offset, unsigned size)
+{
+    imx_int_state *s = (imx_int_state *)opaque;
+
+
+    DPRINTF("read(offset = 0x%x)\n", offset >> 2);
+    switch (offset >> 2) {
+    case 0: /* INTCNTL */
+        return s->intcntl;
+
+    case 1: /* Normal Interrupt Mask Register, NIMASK */
+        return s->intmask;
+
+    case 2: /* Interrupt Enable Number Register, INTENNUM */
+    case 3: /* Interrupt Disable Number Register, INTDISNUM */
+        return 0;
+
+    case 4: /* Interrupt Enabled Number Register High */
+        return s->enabled >> 32;
+
+    case 5: /* Interrupt Enabled Number Register Low */
+        return s->enabled & 0xffffffffULL;
+
+    case 6: /* Interrupt Type Register High */
+        return s->is_fiq >> 32;
+
+    case 7: /* Interrupt Type Register Low */
+        return s->is_fiq & 0xFFFFFFFFULL;
+
+    case 8: /* Normal Interrupt Priority Register 7 */
+    case 9: /* Normal Interrupt Priority Register 6 */
+    case 10:/* Normal Interrupt Priority Register 5 */
+    case 11:/* Normal Interrupt Priority Register 4 */
+    case 12:/* Normal Interrupt Priority Register 3 */
+    case 13:/* Normal Interrupt Priority Register 2 */
+    case 14:/* Normal Interrupt Priority Register 1 */
+    case 15:/* Normal Interrupt Priority Register 0 */
+        return s->prio[15-(offset>>2)];
+
+    case 16: /* Normal interrupt vector and status register */
+    {
+        uint64_t flags = s->pending & s->enabled & ~s->is_fiq;
+        int i = ffsll(flags);
+        if (i) {
+            imx_int_set_irq(opaque, i-1, 0);
+            return (i-1) << 16;
+        }
+        return 0xFFFFULL<<16;
+    }
+    case 17:/* Fast Interrupt vector and status register */
+    {
+        uint64_t flags = s->pending & s->enabled & s->is_fiq;
+        int i = ffsll(flags);
+        if (i) {
+            imx_int_set_irq(opaque, i-1, 0);
+            return (i-1) << 16;
+        }
+        return 0xFFFF<<16;
+    }
+    case 18:/* Interrupt source register high */
+        return s->pending >> 32;
+
+    case 19:/* Interrupt source register low */
+        return s->pending & 0xFFFFFFFFULL;
+
+    case 20:/* Interrupt Force Register high */
+    case 21:/* Interrupt Force Register low */
+        return 0;
+
+    case 22:/* Normal Interrupt Pending Register High */
+        return (s->pending & s->enabled & ~s->is_fiq) >> 32;
+
+    case 23:/* Normal Interrupt Pending Register Low */
+        return (s->pending & s->enabled & ~s->is_fiq) & 0xFFFFFFFFULL;
+
+    case 24: /* Fast Interrupt Pending Register High  */
+        return (s->pending & s->enabled & s->is_fiq) >> 32;
+
+    case 25: /* Fast Interrupt Pending Register Low  */
+        return (s->pending & s->enabled & s->is_fiq) & 0xFFFFFFFFULL;
+
+    case 0x40:            /* AVIC vector 0, use for WFI WAR */
+        return 0x4;
+
+    default:
+        scream("imx_int_read: Bad offset 0x%x\n", (int)offset);
+        return 0;
+    }
+}
+
+static void imx_int_write(void *opaque, target_phys_addr_t offset,
+                          uint64_t val, unsigned size)
+{
+    imx_int_state *s = (imx_int_state *)opaque;
+
+    /* Vector Registers not yet supported */
+    if (offset >= 0x100 && offset <= 0x2fc) {
+        DPRINTF("imx_int_write to vector register %d\n",
+                (offset - 0x100)>>2);
+        return;
+    }
+
+    DPRINTF("imx_int_write(0x%x) = %x\n",
+            (unsigned int)offset>>2, (unsigned int)val);
+    switch (offset >> 2) {
+    case 0: /* Interrupt Control Register, INTCNTL */
+        s->intcntl = val;
+        break;
+
+    case 1: /* Normal Interrupt Mask Register, NIMASK */
+        s->intmask = val;
+        break;
+
+    case 2: /* Interrupt Enable Number Register, INTENNUM */
+        DPRINTF("enable(%d)\n", (int)val);
+        s->enabled |= (1ULL << val);
+        break;
+
+    case 3: /* Interrupt Disable Number Register, INTDISNUM */
+        s->enabled &= ~(1ULL << val);
+        DPRINTF("disabled(%d)\n", (int)val);
+        break;
+
+    case 4: /* Interrupt Enable Number Register High */
+        s->enabled = (s->enabled & 0xffffffffULL) | (val << 32);
+        break;
+
+    case 5: /* Interrupt Enable Number Register Low */
+        s->enabled = (s->enabled & 0xffffffff00000000ULL) | val;
+        break;
+
+    case 6: /* Interrupt Type Register High */
+        s->is_fiq = (s->is_fiq & 0xffffffffULL) | (val << 32);
+        break;
+
+    case 7: /* Interrupt Type Register Low */
+        s->is_fiq = (s->is_fiq & 0xffffffff00000000ULL) | val;
+        break;
+
+    case 8: /* Normal Interrupt Priority Register 7 */
+    case 9: /* Normal Interrupt Priority Register 6 */
+    case 10:/* Normal Interrupt Priority Register 5 */
+    case 11:/* Normal Interrupt Priority Register 4 */
+    case 12:/* Normal Interrupt Priority Register 3 */
+    case 13:/* Normal Interrupt Priority Register 2 */
+    case 14:/* Normal Interrupt Priority Register 1 */
+    case 15:/* Normal Interrupt Priority Register 0 */
+        s->prio[15-(offset>>2)] = val;
+        return;
+
+        /* Read-only registers, writes ignored */
+    case 16:/* Normal Interrupt Vector and Status register */
+    case 17:/* Fast Interrupt vector and status register */
+    case 18:/* Interrupt source register high */
+    case 19:/* Interrupt source register low */
+        return;
+
+    case 20:/* Interrupt Force Register high */
+        s->pending = (s->pending & 0xffffffffULL) | (val << 32);
+        break;
+
+    case 21:/* Interrupt Force Register low */
+        s->pending = (s->pending & 0xffffffff00000000ULL) | val;
+        break;
+
+    case 22:/* Normal Interrupt Pending Register High */
+    case 23:/* Normal Interrupt Pending Register Low */
+    case 24: /* Fast Interrupt Pending Register High  */
+    case 25: /* Fast Interrupt Pending Register Low  */
+        return;
+
+    default:
+        scream("imx_int_write: Bad offset %x\n", (int)offset);
+    }
+    imx_int_update(s);
+}
+
+static const MemoryRegionOps imx_int_ops = {
+    .read = imx_int_read,
+    .write = imx_int_write,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static void imx_int_reset(imx_int_state *s)
+{
+    s->intmask = 0x1f;
+    s->enabled = 0;
+}
+
+static int imx_int_init(SysBusDevice *dev)
+{
+    imx_int_state *s = FROM_SYSBUS(imx_int_state, dev);;
+
+    memory_region_init_io(&s->iomem, &imx_int_ops, s, "imx_int", 0x1000);
+    sysbus_init_mmio_region(dev, &s->iomem);
+
+    qdev_init_gpio_in(&dev->qdev, imx_int_set_irq, IMX_INT_NUM_IRQS);
+    sysbus_init_irq(dev, &s->irq);
+    sysbus_init_irq(dev, &s->fiq);
+
+    imx_int_reset(s);
+
+    vmstate_register(&dev->qdev, -1, &vmstate_imx_avic, s);
+    return 0;
+}
+
+static void imx_int_register_devices(void)
+{
+    SysBusDeviceInfo *info = g_malloc0(sizeof *info);
+    info->qdev.name = "imx_int";
+    info->qdev.desc = "i.MX Advanced Vector Interrupt Controller";
+    info->qdev.size = sizeof(imx_int_state);
+    info->init = imx_int_init;
+    sysbus_register_withprop(info);
+}
+
+device_init(imx_int_register_devices)
+

--
Dr Peter Chubb  http://www.gelato.unsw.edu.au  peterc AT gelato.unsw.edu.au
http://www.ertos.nicta.com.au           ERTOS within National ICT Australia