hw/intc: Add LoongArch extioi interrupt controller(EIOINTC)

This patch realize the EIOINTC interrupt controller.

Signed-off-by: Xiaojuan Yang <yangxiaojuan@loongson.cn>
Signed-off-by: Song Gao <gaosong@loongson.cn>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20220606124333.2060567-35-yangxiaojuan@loongson.cn>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

4 files changed, 322 insertions, 0 deletions

diff --git a/hw/intc/Kconfig b/hw/intc/Kconfig
index 58f550b..ecd2883 100644
--- a/hw/intc/Kconfig
+++ b/hw/intc/Kconfig
@@ -99,3 +99,6 @@ config LOONGARCH_PCH_MSI
     select MSI_NONBROKEN
     bool
     select UNIMP
+
+config LOONGARCH_EXTIOI
+    bool
diff --git a/hw/intc/loongarch_extioi.c b/hw/intc/loongarch_extioi.c
new file mode 100644
index 0000000..2280396
--- /dev/null
+++ b/hw/intc/loongarch_extioi.c
@@ -0,0 +1,312 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Loongson 3A5000 ext interrupt controller emulation
+ *
+ * Copyright (C) 2021 Loongson Technology Corporation Limited
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/module.h"
+#include "qemu/log.h"
+#include "hw/irq.h"
+#include "hw/sysbus.h"
+#include "hw/loongarch/virt.h"
+#include "hw/qdev-properties.h"
+#include "exec/address-spaces.h"
+#include "hw/intc/loongarch_extioi.h"
+#include "migration/vmstate.h"
+#include "trace.h"
+
+
+static void extioi_update_irq(LoongArchExtIOI *s, int irq, int level)
+{
+    int ipnum, cpu, found, irq_index, irq_mask;
+
+    ipnum = s->sw_ipmap[irq / 32];
+    cpu = s->sw_coremap[irq];
+    irq_index = irq / 32;
+    irq_mask = 1 << (irq & 0x1f);
+
+    if (level) {
+        /* if not enable return false */
+        if (((s->enable[irq_index]) & irq_mask) == 0) {
+            return;
+        }
+        s->coreisr[cpu][irq_index] |= irq_mask;
+        found = find_first_bit(s->sw_isr[cpu][ipnum], EXTIOI_IRQS);
+        set_bit(irq, s->sw_isr[cpu][ipnum]);
+        if (found < EXTIOI_IRQS) {
+            /* other irq is handling, need not update parent irq level */
+            return;
+        }
+    } else {
+        s->coreisr[cpu][irq_index] &= ~irq_mask;
+        clear_bit(irq, s->sw_isr[cpu][ipnum]);
+        found = find_first_bit(s->sw_isr[cpu][ipnum], EXTIOI_IRQS);
+        if (found < EXTIOI_IRQS) {
+            /* other irq is handling, need not update parent irq level */
+            return;
+        }
+    }
+    qemu_set_irq(s->parent_irq[cpu][ipnum], level);
+}
+
+static void extioi_setirq(void *opaque, int irq, int level)
+{
+    LoongArchExtIOI *s = LOONGARCH_EXTIOI(opaque);
+    trace_loongarch_extioi_setirq(irq, level);
+    if (level) {
+        /*
+         * s->isr should be used in vmstate structure,
+         * but it not support 'unsigned long',
+         * so we have to switch it.
+         */
+        set_bit(irq, (unsigned long *)s->isr);
+    } else {
+        clear_bit(irq, (unsigned long *)s->isr);
+    }
+    extioi_update_irq(s, irq, level);
+}
+
+static uint64_t extioi_readw(void *opaque, hwaddr addr, unsigned size)
+{
+    LoongArchExtIOI *s = LOONGARCH_EXTIOI(opaque);
+    unsigned long offset = addr & 0xffff;
+    uint32_t index, cpu, ret = 0;
+
+    switch (offset) {
+    case EXTIOI_NODETYPE_START ... EXTIOI_NODETYPE_END - 1:
+        index = (offset - EXTIOI_NODETYPE_START) >> 2;
+        ret = s->nodetype[index];
+        break;
+    case EXTIOI_IPMAP_START ... EXTIOI_IPMAP_END - 1:
+        index = (offset - EXTIOI_IPMAP_START) >> 2;
+        ret = s->ipmap[index];
+        break;
+    case EXTIOI_ENABLE_START ... EXTIOI_ENABLE_END - 1:
+        index = (offset - EXTIOI_ENABLE_START) >> 2;
+        ret = s->enable[index];
+        break;
+    case EXTIOI_BOUNCE_START ... EXTIOI_BOUNCE_END - 1:
+        index = (offset - EXTIOI_BOUNCE_START) >> 2;
+        ret = s->bounce[index];
+        break;
+    case EXTIOI_COREISR_START ... EXTIOI_COREISR_END - 1:
+        index = ((offset - EXTIOI_COREISR_START) & 0x1f) >> 2;
+        cpu = ((offset - EXTIOI_COREISR_START) >> 8) & 0x3;
+        ret = s->coreisr[cpu][index];
+        break;
+    case EXTIOI_COREMAP_START ... EXTIOI_COREMAP_END - 1:
+        index = (offset - EXTIOI_COREMAP_START) >> 2;
+        ret = s->coremap[index];
+        break;
+    default:
+        break;
+    }
+
+    trace_loongarch_extioi_readw(addr, ret);
+    return ret;
+}
+
+static inline void extioi_enable_irq(LoongArchExtIOI *s, int index,\
+                                     uint32_t mask, int level)
+{
+    uint32_t val;
+    int irq;
+
+    val = mask & s->isr[index];
+    irq = ctz32(val);
+    while (irq != 32) {
+        /*
+         * enable bit change from 0 to 1,
+         * need to update irq by pending bits
+         */
+        extioi_update_irq(s, irq + index * 32, level);
+        val &= ~(1 << irq);
+        irq = ctz32(val);
+    }
+}
+
+static void extioi_writew(void *opaque, hwaddr addr,
+                          uint64_t val, unsigned size)
+{
+    LoongArchExtIOI *s = LOONGARCH_EXTIOI(opaque);
+    int i, cpu, index, old_data, irq;
+    uint32_t offset;
+
+    trace_loongarch_extioi_writew(addr, val);
+    offset = addr & 0xffff;
+
+    switch (offset) {
+    case EXTIOI_NODETYPE_START ... EXTIOI_NODETYPE_END - 1:
+        index = (offset - EXTIOI_NODETYPE_START) >> 2;
+        s->nodetype[index] = val;
+        break;
+    case EXTIOI_IPMAP_START ... EXTIOI_IPMAP_END - 1:
+        /*
+         * ipmap cannot be set at runtime, can be set only at the beginning
+         * of intr driver, need not update upper irq level
+         */
+        index = (offset - EXTIOI_IPMAP_START) >> 2;
+        s->ipmap[index] = val;
+        /*
+         * loongarch only support little endian,
+         * so we paresd the value with little endian.
+         */
+        val = cpu_to_le64(val);
+        for (i = 0; i < 4; i++) {
+            uint8_t ipnum;
+            ipnum = val & 0xff;
+            ipnum = ctz32(ipnum);
+            ipnum = (ipnum >= 4) ? 0 : ipnum;
+            s->sw_ipmap[index * 4 + i] = ipnum;
+            val = val >> 8;
+        }
+
+        break;
+    case EXTIOI_ENABLE_START ... EXTIOI_ENABLE_END - 1:
+        index = (offset - EXTIOI_ENABLE_START) >> 2;
+        old_data = s->enable[index];
+        s->enable[index] = val;
+
+        /* unmask irq */
+        val = s->enable[index] & ~old_data;
+        extioi_enable_irq(s, index, val, 1);
+
+        /* mask irq */
+        val = ~s->enable[index] & old_data;
+        extioi_enable_irq(s, index, val, 0);
+        break;
+    case EXTIOI_BOUNCE_START ... EXTIOI_BOUNCE_END - 1:
+        /* do not emulate hw bounced irq routing */
+        index = (offset - EXTIOI_BOUNCE_START) >> 2;
+        s->bounce[index] = val;
+        break;
+    case EXTIOI_COREISR_START ... EXTIOI_COREISR_END - 1:
+        index = ((offset - EXTIOI_COREISR_START) & 0x1f) >> 2;
+        cpu = ((offset - EXTIOI_COREISR_START) >> 8) & 0x3;
+        old_data = s->coreisr[cpu][index];
+        s->coreisr[cpu][index] = old_data & ~val;
+        /* write 1 to clear interrrupt */
+        old_data &= val;
+        irq = ctz32(old_data);
+        while (irq != 32) {
+            extioi_update_irq(s, irq + index * 32, 0);
+            old_data &= ~(1 << irq);
+            irq = ctz32(old_data);
+        }
+        break;
+    case EXTIOI_COREMAP_START ... EXTIOI_COREMAP_END - 1:
+        irq = offset - EXTIOI_COREMAP_START;
+        index = irq / 4;
+        s->coremap[index] = val;
+        /*
+         * loongarch only support little endian,
+         * so we paresd the value with little endian.
+         */
+        val = cpu_to_le64(val);
+
+        for (i = 0; i < 4; i++) {
+            cpu = val & 0xff;
+            cpu = ctz32(cpu);
+            cpu = (cpu >= 4) ? 0 : cpu;
+            val = val >> 8;
+
+            if (s->sw_coremap[irq + i] == cpu) {
+                continue;
+            }
+
+            if (test_bit(irq, (unsigned long *)s->isr)) {
+                /*
+                 * lower irq at old cpu and raise irq at new cpu
+                 */
+                extioi_update_irq(s, irq + i, 0);
+                s->sw_coremap[irq + i] = cpu;
+                extioi_update_irq(s, irq + i, 1);
+            } else {
+                s->sw_coremap[irq + i] = cpu;
+            }
+        }
+        break;
+    default:
+        break;
+    }
+}
+
+static const MemoryRegionOps extioi_ops = {
+    .read = extioi_readw,
+    .write = extioi_writew,
+    .impl.min_access_size = 4,
+    .impl.max_access_size = 4,
+    .valid.min_access_size = 4,
+    .valid.max_access_size = 8,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+};
+
+static const VMStateDescription vmstate_loongarch_extioi = {
+    .name = TYPE_LOONGARCH_EXTIOI,
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32_ARRAY(bounce, LoongArchExtIOI, EXTIOI_IRQS_GROUP_COUNT),
+        VMSTATE_UINT32_2DARRAY(coreisr, LoongArchExtIOI, LOONGARCH_MAX_VCPUS,
+                               EXTIOI_IRQS_GROUP_COUNT),
+        VMSTATE_UINT32_ARRAY(nodetype, LoongArchExtIOI,
+                             EXTIOI_IRQS_NODETYPE_COUNT / 2),
+        VMSTATE_UINT32_ARRAY(enable, LoongArchExtIOI, EXTIOI_IRQS / 32),
+        VMSTATE_UINT32_ARRAY(isr, LoongArchExtIOI, EXTIOI_IRQS / 32),
+        VMSTATE_UINT32_ARRAY(ipmap, LoongArchExtIOI, EXTIOI_IRQS_IPMAP_SIZE / 4),
+        VMSTATE_UINT32_ARRAY(coremap, LoongArchExtIOI, EXTIOI_IRQS / 4),
+        VMSTATE_UINT8_ARRAY(sw_ipmap, LoongArchExtIOI, EXTIOI_IRQS_IPMAP_SIZE),
+        VMSTATE_UINT8_ARRAY(sw_coremap, LoongArchExtIOI, EXTIOI_IRQS),
+
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static void loongarch_extioi_instance_init(Object *obj)
+{
+    SysBusDevice *dev = SYS_BUS_DEVICE(obj);
+    LoongArchExtIOI *s = LOONGARCH_EXTIOI(obj);
+    int i, cpu, pin;
+
+    for (i = 0; i < EXTIOI_IRQS; i++) {
+        sysbus_init_irq(SYS_BUS_DEVICE(dev), &s->irq[i]);
+    }
+
+    qdev_init_gpio_in(DEVICE(obj), extioi_setirq, EXTIOI_IRQS);
+
+    for (cpu = 0; cpu < LOONGARCH_MAX_VCPUS; cpu++) {
+        memory_region_init_io(&s->extioi_iocsr_mem[cpu], OBJECT(s), &extioi_ops,
+                              s, "extioi_iocsr", 0x900);
+        sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->extioi_iocsr_mem[cpu]);
+        for (pin = 0; pin < LS3A_INTC_IP; pin++) {
+            qdev_init_gpio_out(DEVICE(obj), &s->parent_irq[cpu][pin], 1);
+        }
+    }
+    memory_region_init_io(&s->extioi_system_mem, OBJECT(s), &extioi_ops,
+                          s, "extioi_system_mem", 0x900);
+    sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->extioi_system_mem);
+}
+
+static void loongarch_extioi_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->vmsd = &vmstate_loongarch_extioi;
+}
+
+static const TypeInfo loongarch_extioi_info = {
+    .name          = TYPE_LOONGARCH_EXTIOI,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_init = loongarch_extioi_instance_init,
+    .instance_size = sizeof(struct LoongArchExtIOI),
+    .class_init    = loongarch_extioi_class_init,
+};
+
+static void loongarch_extioi_register_types(void)
+{
+    type_register_static(&loongarch_extioi_info);
+}
+
+type_init(loongarch_extioi_register_types)
diff --git a/hw/intc/meson.build b/hw/intc/meson.build
index 1d407c0..bcbf22f 100644
--- a/hw/intc/meson.build
+++ b/hw/intc/meson.build
@@ -66,3 +66,4 @@ specific_ss.add(when: 'CONFIG_NIOS2_VIC', if_true: files('nios2_vic.c'))
 specific_ss.add(when: 'CONFIG_LOONGARCH_IPI', if_true: files('loongarch_ipi.c'))
 specific_ss.add(when: 'CONFIG_LOONGARCH_PCH_PIC', if_true: files('loongarch_pch_pic.c'))
 specific_ss.add(when: 'CONFIG_LOONGARCH_PCH_MSI', if_true: files('loongarch_pch_msi.c'))
+specific_ss.add(when: 'CONFIG_LOONGARCH_EXTIOI', if_true: files('loongarch_extioi.c'))
diff --git a/hw/intc/trace-events b/hw/intc/trace-events
index 63c9851..0a90c1c 100644
--- a/hw/intc/trace-events
+++ b/hw/intc/trace-events
@@ -303,3 +303,9 @@ loongarch_pch_pic_writeb(unsigned size, uint64_t addr, uint64_t val) "size: %u a
 
 # loongarch_pch_msi.c
 loongarch_msi_set_irq(int irq_num) "set msi irq %d"
+
+# loongarch_extioi.c
+loongarch_extioi_setirq(int irq, int level) "set extirq irq %d level %d"
+loongarch_extioi_readw(uint64_t addr, uint32_t val) "addr: 0x%"PRIx64 "val: 0x%x"
+loongarch_extioi_writew(uint64_t addr, uint64_t val) "addr: 0x%"PRIx64 "val: 0x%" PRIx64
+