aspeed/sli: Add AST2700 support

AST2700 SLI engine is designed to accelerate the
throughput between cross-die connections.
It have CPU_SLI at CPU die and IO_SLI at IO die.

Introduce dummy AST2700 SLI and SLIIO models.

Signed-off-by: Troy Lee <troy_lee@aspeedtech.com>
Signed-off-by: Jamin Lin <jamin_lin@aspeedtech.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
diff --git a/hw/misc/aspeed_sli.c b/hw/misc/aspeed_sli.c
new file mode 100644
index 0000000..fe720ea
--- /dev/null
+++ b/hw/misc/aspeed_sli.c
@@ -0,0 +1,177 @@
+/*
+ * ASPEED SLI Controller
+ *
+ * Copyright (C) 2024 ASPEED Technology Inc.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/log.h"
+#include "qemu/error-report.h"
+#include "hw/qdev-properties.h"
+#include "hw/misc/aspeed_sli.h"
+#include "qapi/error.h"
+#include "migration/vmstate.h"
+#include "trace.h"
+
+#define SLI_REGION_SIZE 0x500
+#define TO_REG(addr) ((addr) >> 2)
+
+static uint64_t aspeed_sli_read(void *opaque, hwaddr addr, unsigned int size)
+{
+    AspeedSLIState *s = ASPEED_SLI(opaque);
+    int reg = TO_REG(addr);
+
+    if (reg >= ARRAY_SIZE(s->regs)) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: Out-of-bounds read at offset 0x%" HWADDR_PRIx "\n",
+                      __func__, addr);
+        return 0;
+    }
+
+    trace_aspeed_sli_read(addr, size, s->regs[reg]);
+    return s->regs[reg];
+}
+
+static void aspeed_sli_write(void *opaque, hwaddr addr, uint64_t data,
+                              unsigned int size)
+{
+    AspeedSLIState *s = ASPEED_SLI(opaque);
+    int reg = TO_REG(addr);
+
+    if (reg >= ARRAY_SIZE(s->regs)) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: Out-of-bounds write at offset 0x%" HWADDR_PRIx "\n",
+                      __func__, addr);
+        return;
+    }
+
+    trace_aspeed_sli_write(addr, size, data);
+    s->regs[reg] = data;
+}
+
+static uint64_t aspeed_sliio_read(void *opaque, hwaddr addr, unsigned int size)
+{
+    AspeedSLIState *s = ASPEED_SLI(opaque);
+    int reg = TO_REG(addr);
+
+    if (reg >= ARRAY_SIZE(s->regs)) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: Out-of-bounds read at offset 0x%" HWADDR_PRIx "\n",
+                      __func__, addr);
+        return 0;
+    }
+
+    trace_aspeed_sliio_read(addr, size, s->regs[reg]);
+    return s->regs[reg];
+}
+
+static void aspeed_sliio_write(void *opaque, hwaddr addr, uint64_t data,
+                              unsigned int size)
+{
+    AspeedSLIState *s = ASPEED_SLI(opaque);
+    int reg = TO_REG(addr);
+
+    if (reg >= ARRAY_SIZE(s->regs)) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "%s: Out-of-bounds write at offset 0x%" HWADDR_PRIx "\n",
+                      __func__, addr);
+        return;
+    }
+
+    trace_aspeed_sliio_write(addr, size, data);
+    s->regs[reg] = data;
+}
+
+static const MemoryRegionOps aspeed_sli_ops = {
+    .read = aspeed_sli_read,
+    .write = aspeed_sli_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .valid = {
+        .min_access_size = 1,
+        .max_access_size = 4,
+    },
+};
+
+static const MemoryRegionOps aspeed_sliio_ops = {
+    .read = aspeed_sliio_read,
+    .write = aspeed_sliio_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .valid = {
+        .min_access_size = 1,
+        .max_access_size = 4,
+    },
+};
+
+static void aspeed_sli_realize(DeviceState *dev, Error **errp)
+{
+    AspeedSLIState *s = ASPEED_SLI(dev);
+    SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
+
+    memory_region_init_io(&s->iomem, OBJECT(s), &aspeed_sli_ops, s,
+                          TYPE_ASPEED_SLI, SLI_REGION_SIZE);
+    sysbus_init_mmio(sbd, &s->iomem);
+}
+
+static void aspeed_sliio_realize(DeviceState *dev, Error **errp)
+{
+    AspeedSLIState *s = ASPEED_SLI(dev);
+    SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
+
+    memory_region_init_io(&s->iomem, OBJECT(s), &aspeed_sliio_ops, s,
+                          TYPE_ASPEED_SLI, SLI_REGION_SIZE);
+    sysbus_init_mmio(sbd, &s->iomem);
+}
+
+static void aspeed_sli_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->desc = "Aspeed SLI Controller";
+    dc->realize = aspeed_sli_realize;
+}
+
+static const TypeInfo aspeed_sli_info = {
+    .name          = TYPE_ASPEED_SLI,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(AspeedSLIState),
+    .class_init    = aspeed_sli_class_init,
+    .abstract      = true,
+};
+
+static void aspeed_2700_sli_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->desc = "AST2700 SLI Controller";
+}
+
+static void aspeed_2700_sliio_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->desc = "AST2700 I/O SLI Controller";
+    dc->realize = aspeed_sliio_realize;
+}
+
+static const TypeInfo aspeed_2700_sli_info = {
+    .name           = TYPE_ASPEED_2700_SLI,
+    .parent         = TYPE_ASPEED_SLI,
+    .class_init     = aspeed_2700_sli_class_init,
+};
+
+static const TypeInfo aspeed_2700_sliio_info = {
+    .name           = TYPE_ASPEED_2700_SLIIO,
+    .parent         = TYPE_ASPEED_SLI,
+    .class_init     = aspeed_2700_sliio_class_init,
+};
+
+static void aspeed_sli_register_types(void)
+{
+    type_register_static(&aspeed_sli_info);
+    type_register_static(&aspeed_2700_sli_info);
+    type_register_static(&aspeed_2700_sliio_info);
+}
+
+type_init(aspeed_sli_register_types);
diff --git a/hw/misc/meson.build b/hw/misc/meson.build
index 86596a3..2ca8717 100644
--- a/hw/misc/meson.build
+++ b/hw/misc/meson.build
@@ -136,7 +136,8 @@
   'aspeed_sbc.c',
   'aspeed_sdmc.c',
   'aspeed_xdma.c',
-  'aspeed_peci.c'))
+  'aspeed_peci.c',
+  'aspeed_sli.c'))
 
 system_ss.add(when: 'CONFIG_MSF2', if_true: files('msf2-sysreg.c'))
 system_ss.add(when: 'CONFIG_NRF51_SOC', if_true: files('nrf51_rng.c'))
diff --git a/hw/misc/trace-events b/hw/misc/trace-events
index 5d241cb..e13b648 100644
--- a/hw/misc/trace-events
+++ b/hw/misc/trace-events
@@ -351,3 +351,10 @@
 # iosb.c
 iosb_read(int reg, uint64_t value, unsigned int size) "reg=0x%x value=0x%"PRIx64" size=%u"
 iosb_write(int reg, uint64_t value, unsigned int size) "reg=0x%x value=0x%"PRIx64" size=%u"
+
+# aspeed_sli.c
+aspeed_sli_write(uint64_t offset, unsigned int size, uint32_t data) "To 0x%" PRIx64 " of size %u: 0x%" PRIx32
+aspeed_sli_read(uint64_t offset, unsigned int size, uint32_t data) "To 0x%" PRIx64 " of size %u: 0x%" PRIx32
+aspeed_sliio_write(uint64_t offset, unsigned int size, uint32_t data) "To 0x%" PRIx64 " of size %u: 0x%" PRIx32
+aspeed_sliio_read(uint64_t offset, unsigned int size, uint32_t data) "To 0x%" PRIx64 " of size %u: 0x%" PRIx32
+
diff --git a/include/hw/misc/aspeed_sli.h b/include/hw/misc/aspeed_sli.h
new file mode 100644
index 0000000..23f346a
--- /dev/null
+++ b/include/hw/misc/aspeed_sli.h
@@ -0,0 +1,27 @@
+/*
+ * ASPEED SLI Controller
+ *
+ * Copyright (C) 2024 ASPEED Technology Inc.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+#ifndef ASPEED_SLI_H
+#define ASPEED_SLI_H
+
+#include "hw/sysbus.h"
+
+#define TYPE_ASPEED_SLI "aspeed.sli"
+#define TYPE_ASPEED_2700_SLI TYPE_ASPEED_SLI "-ast2700"
+#define TYPE_ASPEED_2700_SLIIO TYPE_ASPEED_SLI "io" "-ast2700"
+OBJECT_DECLARE_SIMPLE_TYPE(AspeedSLIState, ASPEED_SLI)
+
+#define ASPEED_SLI_NR_REGS  (0x500 >> 2)
+
+struct AspeedSLIState {
+    SysBusDevice parent;
+    MemoryRegion iomem;
+
+    uint32_t regs[ASPEED_SLI_NR_REGS];
+};
+
+#endif /* ASPEED_SLI_H */