[RFC PATCH v2 18/30] hw/loongarch: Add LoongArch ipi interrupt support(IPI)

[Xiaojuan Yang <yangxiaojuan@loongson.cn>]

This patch realize the IPI interrupt controller.

Signed-off-by: Xiaojuan Yang <yangxiaojuan@loongson.cn>
Signed-off-by: Song Gao <gaosong@loongson.cn>
---
 hw/loongarch/ipi.c               | 144 +++++++++++++++++++++++++++++++
 hw/loongarch/ls3a5000_virt.c     |   1 +
 hw/loongarch/meson.build         |   2 +-
 include/hw/loongarch/gipi.h      |  37 ++++++++
 include/hw/loongarch/loongarch.h |   4 +
 target/loongarch/cpu.h           |   1 +
 6 files changed, 188 insertions(+), 1 deletion(-)
 create mode 100644 hw/loongarch/ipi.c
 create mode 100644 include/hw/loongarch/gipi.h

diff --git a/hw/loongarch/ipi.c b/hw/loongarch/ipi.c
new file mode 100644
index 0000000000..4902205ff5
--- /dev/null
+++ b/hw/loongarch/ipi.c
@@ -0,0 +1,144 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * LoongArch ipi interrupt support
+ *
+ * Copyright (C) 2021 Loongson Technology Corporation Limited
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/units.h"
+#include "qapi/error.h"
+#include "exec/address-spaces.h"
+#include "hw/hw.h"
+#include "hw/irq.h"
+#include "sysemu/sysemu.h"
+#include "sysemu/cpus.h"
+#include "cpu.h"
+#include "qemu/log.h"
+#include "hw/loongarch/loongarch.h"
+#include "migration/vmstate.h"
+
+static const VMStateDescription vmstate_gipi_core = {
+    .name = "gipi-single",
+    .version_id = 0,
+    .minimum_version_id = 0,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32(status, gipi_core),
+        VMSTATE_UINT32(en, gipi_core),
+        VMSTATE_UINT32(set, gipi_core),
+        VMSTATE_UINT32(clear, gipi_core),
+        VMSTATE_UINT64_ARRAY(buf, gipi_core, MAX_GIPI_MBX_NUM),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static const VMStateDescription vmstate_gipi = {
+    .name = "gipi",
+    .version_id = 0,
+    .minimum_version_id = 0,
+    .fields = (VMStateField[]) {
+        VMSTATE_STRUCT_ARRAY(core, gipiState, MAX_GIPI_CORE_NUM, 0,
+                             vmstate_gipi_core, gipi_core),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static void gipi_writel(void *opaque, hwaddr addr, uint64_t val, unsigned size)
+{
+    gipi_core *s = opaque;
+    void *pbuf;
+
+    if (size != 4) {
+        hw_error("size not 4");
+    }
+    addr &= 0xff;
+    switch (addr) {
+    case CORE_STATUS_OFF:
+        hw_error("CORE_SET_OFF Can't be write\n");
+        break;
+    case CORE_EN_OFF:
+        s->en = val;
+        break;
+    case CORE_SET_OFF:
+        s->status |= val;
+        if (s->status != 0) {
+            qemu_irq_raise(s->irq);
+        }
+        break;
+    case CORE_CLEAR_OFF:
+        s->status ^= val;
+        if (s->status == 0) {
+            qemu_irq_lower(s->irq);
+        }
+        break;
+    case CORE_BUF_20 ... CORE_BUF_38:
+        pbuf =  (void *)s->buf + (addr - 0x20);
+        *(unsigned int *)pbuf = val;
+        break;
+    default:
+        break;
+    }
+}
+
+static uint64_t gipi_readl(void *opaque, hwaddr addr, unsigned size)
+{
+    gipi_core *s = opaque;
+    uint64_t ret = 0;
+    void *pbuf;
+
+    addr &= 0xff;
+    if (size != 4) {
+        hw_error("size not 4 %d\n", size);
+    }
+    switch (addr) {
+    case CORE_STATUS_OFF:
+        ret = s->status;
+        break;
+    case CORE_EN_OFF:
+        ret = s->en;
+        break;
+    case CORE_SET_OFF:
+        ret = 0;
+        break;
+    case CORE_CLEAR_OFF:
+        ret = 0;
+        break;
+    case CORE_BUF_20 ... CORE_BUF_38:
+        pbuf =  (void *)s->buf + (addr - 0x20);
+        ret = *(unsigned int *)pbuf;
+        break;
+    default:
+        break;
+    }
+
+    return ret;
+}
+
+static const MemoryRegionOps gipi_ops = {
+    .read = gipi_readl,
+    .write = gipi_writel,
+    .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+int cpu_init_ipi(LoongArchMachineState *lams, qemu_irq parent, int cpu)
+{
+    int core_num = cpu % 4;
+    hwaddr addr;
+    MemoryRegion *region;
+    char str[32];
+
+    if (lams->gipi == NULL) {
+        lams->gipi = g_malloc0(sizeof(gipiState));
+        vmstate_register(NULL, 0, &vmstate_gipi, lams->gipi);
+    }
+
+    lams->gipi->core[cpu].irq = parent;
+
+    addr = SMP_GIPI_MAILBOX + core_num * 0x100;
+    region = g_new(MemoryRegion, 1);
+    sprintf(str, "gipi%d", cpu);
+    memory_region_init_io(region, NULL, &gipi_ops,
+                          &lams->gipi->core[cpu], str, 0x100);
+    memory_region_add_subregion(lams->system_iocsr, addr, region);
+    return 0;
+}
diff --git a/hw/loongarch/ls3a5000_virt.c b/hw/loongarch/ls3a5000_virt.c
index 37d6b1ec88..bd79df96df 100644
--- a/hw/loongarch/ls3a5000_virt.c
+++ b/hw/loongarch/ls3a5000_virt.c
@@ -153,6 +153,7 @@ static void ls3a5000_virt_init(MachineState *machine)
         /* Init CPU internal devices */
         cpu_loongarch_init_irq(cpu);
         cpu_loongarch_clock_init(cpu);
+        cpu_init_ipi(lams, env->irq[IRQ_IPI], i);
         qemu_register_reset(main_cpu_reset, cpu);
     }
 
diff --git a/hw/loongarch/meson.build b/hw/loongarch/meson.build
index a972210680..1bd209c9eb 100644
--- a/hw/loongarch/meson.build
+++ b/hw/loongarch/meson.build
@@ -1,5 +1,5 @@
 loongarch_ss = ss.source_set()
 loongarch_ss.add(files('loongarch_int.c'))
-loongarch_ss.add(when: 'CONFIG_LOONGSON_3A5000', if_true: files('ls3a5000_virt.c'))
+loongarch_ss.add(when: 'CONFIG_LOONGSON_3A5000', if_true: files('ls3a5000_virt.c', 'ipi.c'))
 
 hw_arch += {'loongarch': loongarch_ss}
diff --git a/include/hw/loongarch/gipi.h b/include/hw/loongarch/gipi.h
new file mode 100644
index 0000000000..244d4e3ecf
--- /dev/null
+++ b/include/hw/loongarch/gipi.h
@@ -0,0 +1,37 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * LoongArch ipi interrupt header files
+ *
+ * Copyright (C) 2021 Loongson Technology Corporation Limited
+ */
+
+#ifndef HW_LOONGARCH_GIPI_H
+#define HW_LOONGARCH_GIPI_H
+
+#define SMP_GIPI_MAILBOX      0x1000ULL
+#define CORE_STATUS_OFF       0x0
+#define CORE_EN_OFF           0x4
+#define CORE_SET_OFF          0x8
+#define CORE_CLEAR_OFF        0xc
+#define CORE_BUF_20           0x20
+#define CORE_BUF_28           0x28
+#define CORE_BUF_30           0x30
+#define CORE_BUF_38           0x38
+
+#define MAX_GIPI_CORE_NUM      4
+#define MAX_GIPI_MBX_NUM       4
+
+typedef struct gipi_core {
+    uint32_t status;
+    uint32_t en;
+    uint32_t set;
+    uint32_t clear;
+    uint64_t buf[MAX_GIPI_MBX_NUM];
+    qemu_irq irq;
+} gipi_core;
+
+typedef struct gipiState {
+    gipi_core core[MAX_GIPI_CORE_NUM];
+} gipiState;
+
+#endif
diff --git a/include/hw/loongarch/loongarch.h b/include/hw/loongarch/loongarch.h
index 8538697e5f..54cc875e6d 100644
--- a/include/hw/loongarch/loongarch.h
+++ b/include/hw/loongarch/loongarch.h
@@ -12,6 +12,7 @@
 #include "qemu-common.h"
 #include "hw/boards.h"
 #include "qemu/queue.h"
+#include "hw/loongarch/gipi.h"
 
 #define LOONGARCH_MAX_VCPUS     4
 #define PM_MMIO_ADDR            0x10080000UL
@@ -38,6 +39,8 @@ typedef struct LoongArchMachineState {
 
     AddressSpace *address_space_iocsr;
     MemoryRegion *system_iocsr;
+
+    gipiState   *gipi;
 } LoongArchMachineState;
 
 #define TYPE_LOONGARCH_MACHINE  MACHINE_TYPE_NAME("loongson7a")
@@ -45,4 +48,5 @@ DECLARE_INSTANCE_CHECKER(LoongArchMachineState, LOONGARCH_MACHINE,
                          TYPE_LOONGARCH_MACHINE)
 
 void cpu_loongarch_init_irq(LoongArchCPU *cpu);
+int cpu_init_ipi(LoongArchMachineState *lams, qemu_irq irq, int cpu);
 #endif
diff --git a/target/loongarch/cpu.h b/target/loongarch/cpu.h
index 77afe9e26a..b7ef0b8b3c 100644
--- a/target/loongarch/cpu.h
+++ b/target/loongarch/cpu.h
@@ -152,6 +152,7 @@ extern const char * const fregnames[];
 
 #define N_IRQS      14
 #define IRQ_TIMER   11
+#define IRQ_IPI     12
 
 /*
  * LoongArch cpu has 4 priv level, now only 2 mode used.
-- 
2.27.0