The N1 chiplet handle the high speed i/o traffic over PCIe and others.
The N1 chiplet consists of PowerBus Fabric controller,
nest Memory Management Unit, chiplet control unit and more.

This commit creates a N1 chiplet model and initialize and realize the
pervasive chiplet model where chiplet control registers are implemented.

This commit also implement the read/write method for the powerbus scom
registers

Signed-off-by: Chalapathi V <chalapathi.v@linux.ibm.com>
---
 include/hw/ppc/pnv_n1_chiplet.h |  32 ++++++
 include/hw/ppc/pnv_xscom.h      |   6 ++
 hw/ppc/pnv_n1_chiplet.c         | 173 ++++++++++++++++++++++++++++++++
 hw/ppc/meson.build              |   1 +
 4 files changed, 212 insertions(+)
 create mode 100644 include/hw/ppc/pnv_n1_chiplet.h
 create mode 100644 hw/ppc/pnv_n1_chiplet.c

diff --git a/include/hw/ppc/pnv_n1_chiplet.h b/include/hw/ppc/pnv_n1_chiplet.h
new file mode 100644
index 0000000000..a7ad039668
--- /dev/null
+++ b/include/hw/ppc/pnv_n1_chiplet.h
@@ -0,0 +1,32 @@
+/*
+ * QEMU PowerPC N1 chiplet model
+ *
+ * Copyright (c) 2023, IBM Corporation.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#ifndef PPC_PNV_N1_CHIPLET_H
+#define PPC_PNV_N1_CHIPLET_H
+
+#include "hw/ppc/pnv_nest_pervasive.h"
+
+#define TYPE_PNV_N1_CHIPLET "pnv-N1-chiplet"
+#define PNV_N1_CHIPLET(obj) OBJECT_CHECK(PnvN1Chiplet, (obj), TYPE_PNV_N1_CHIPLET)
+
+typedef struct PnvPbScom {
+    uint64_t mode;
+    uint64_t hp_mode2_curr;
+} PnvPbScom;
+
+typedef struct PnvN1Chiplet {
+    DeviceState  parent;
+    MemoryRegion xscom_pb_eq_mr;
+    MemoryRegion xscom_pb_es_mr;
+    PnvNestChipletPervasive nest_pervasive; /* common pervasive chiplet unit */
+#define PNV_PB_SCOM_EQ_SIZE 8
+    PnvPbScom eq[PNV_PB_SCOM_EQ_SIZE];
+#define PNV_PB_SCOM_ES_SIZE 4
+    PnvPbScom es[PNV_PB_SCOM_ES_SIZE];
+} PnvN1Chiplet;
+#endif /*PPC_PNV_N1_CHIPLET_H */
diff --git a/include/hw/ppc/pnv_xscom.h b/include/hw/ppc/pnv_xscom.h
index 3e15706dec..535ae1dab0 100644
--- a/include/hw/ppc/pnv_xscom.h
+++ b/include/hw/ppc/pnv_xscom.h
@@ -173,6 +173,12 @@ struct PnvXScomInterfaceClass {
 #define PNV10_XSCOM_N1_CHIPLET_CTRL_REGS_BASE      0x3000000
 #define PNV10_XSCOM_CHIPLET_CTRL_REGS_SIZE         0x400
 
+#define PNV10_XSCOM_N1_PB_SCOM_EQ_BASE      0x3011000
+#define PNV10_XSCOM_N1_PB_SCOM_EQ_SIZE      0x200
+
+#define PNV10_XSCOM_N1_PB_SCOM_ES_BASE      0x3011300
+#define PNV10_XSCOM_N1_PB_SCOM_ES_SIZE      0x100
+
 #define PNV10_XSCOM_PEC_NEST_BASE  0x3011800 /* index goes downwards ... */
 #define PNV10_XSCOM_PEC_NEST_SIZE  0x100
 
diff --git a/hw/ppc/pnv_n1_chiplet.c b/hw/ppc/pnv_n1_chiplet.c
new file mode 100644
index 0000000000..03ff9fbad0
--- /dev/null
+++ b/hw/ppc/pnv_n1_chiplet.c
@@ -0,0 +1,173 @@
+/*
+ * QEMU PowerPC N1 chiplet model
+ *
+ * Copyright (c) 2023, IBM Corporation.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/log.h"
+#include "hw/qdev-properties.h"
+#include "hw/ppc/pnv.h"
+#include "hw/ppc/pnv_xscom.h"
+#include "hw/ppc/pnv_n1_chiplet.h"
+#include "hw/ppc/pnv_nest_pervasive.h"
+
+/*
+ * The n1 chiplet contains chiplet control unit,
+ * PowerBus/RaceTrack/Bridge logic, nest Memory Management Unit(nMMU)
+ * and more.
+ *
+ * In this model Nest1 chiplet control registers are modelled via common
+ * nest pervasive model and few PowerBus racetrack registers are modelled.
+ */
+
+#define PB_SCOM_EQ0_HP_MODE2_CURR      0xe
+#define PB_SCOM_ES3_MODE               0x8a
+
+static uint64_t pnv_n1_chiplet_pb_scom_eq_read(void *opaque, hwaddr addr,
+                                                  unsigned size)
+{
+    PnvN1Chiplet *n1_chiplet = PNV_N1_CHIPLET(opaque);
+    uint32_t reg = addr >> 3;
+    uint64_t val = ~0ull;
+
+    switch (reg) {
+    case PB_SCOM_EQ0_HP_MODE2_CURR:
+        val = n1_chiplet->eq[0].hp_mode2_curr;
+        break;
+    default:
+        qemu_log_mask(LOG_UNIMP, "%s: Invalid xscom read at 0x%" PRIx32 "\n",
+                      __func__, reg);
+    }
+    return val;
+}
+
+static void pnv_n1_chiplet_pb_scom_eq_write(void *opaque, hwaddr addr,
+                                               uint64_t val, unsigned size)
+{
+    PnvN1Chiplet *n1_chiplet = PNV_N1_CHIPLET(opaque);
+    uint32_t reg = addr >> 3;
+
+    switch (reg) {
+    case PB_SCOM_EQ0_HP_MODE2_CURR:
+        n1_chiplet->eq[0].hp_mode2_curr = val;
+        break;
+    default:
+        qemu_log_mask(LOG_UNIMP, "%s: Invalid xscom write at 0x%" PRIx32 "\n",
+                      __func__, reg);
+    }
+}
+
+static const MemoryRegionOps pnv_n1_chiplet_pb_scom_eq_ops = {
+    .read = pnv_n1_chiplet_pb_scom_eq_read,
+    .write = pnv_n1_chiplet_pb_scom_eq_write,
+    .valid.min_access_size = 8,
+    .valid.max_access_size = 8,
+    .impl.min_access_size = 8,
+    .impl.max_access_size = 8,
+    .endianness = DEVICE_BIG_ENDIAN,
+};
+
+static uint64_t pnv_n1_chiplet_pb_scom_es_read(void *opaque, hwaddr addr,
+                                          unsigned size)
+{
+    PnvN1Chiplet *n1_chiplet = PNV_N1_CHIPLET(opaque);
+    uint32_t reg = addr >> 3;
+    uint64_t val = ~0ull;
+
+    switch (reg) {
+    case PB_SCOM_ES3_MODE:
+        val = n1_chiplet->es[3].mode;
+        break;
+    default:
+        qemu_log_mask(LOG_UNIMP, "%s: Invalid xscom read at 0x%" PRIx32 "\n",
+                      __func__, reg);
+    }
+    return val;
+}
+
+static void pnv_n1_chiplet_pb_scom_es_write(void *opaque, hwaddr addr,
+                                               uint64_t val, unsigned size)
+{
+    PnvN1Chiplet *n1_chiplet = PNV_N1_CHIPLET(opaque);
+    uint32_t reg = addr >> 3;
+
+    switch (reg) {
+    case PB_SCOM_ES3_MODE:
+        n1_chiplet->es[3].mode = val;
+        break;
+    default:
+        qemu_log_mask(LOG_UNIMP, "%s: Invalid xscom write at 0x%" PRIx32 "\n",
+                      __func__, reg);
+    }
+}
+
+static const MemoryRegionOps pnv_n1_chiplet_pb_scom_es_ops = {
+    .read = pnv_n1_chiplet_pb_scom_es_read,
+    .write = pnv_n1_chiplet_pb_scom_es_write,
+    .valid.min_access_size = 8,
+    .valid.max_access_size = 8,
+    .impl.min_access_size = 8,
+    .impl.max_access_size = 8,
+    .endianness = DEVICE_BIG_ENDIAN,
+};
+
+static void pnv_n1_chiplet_realize(DeviceState *dev, Error **errp)
+{
+    PnvN1Chiplet *n1_chiplet = PNV_N1_CHIPLET(dev);
+
+    /* Realize nest pervasive common chiplet model */
+    if (!qdev_realize(DEVICE(&n1_chiplet->nest_pervasive), NULL, errp)) {
+        return;
+    }
+
+    /* Nest1 chiplet power bus EQ xscom region */
+    pnv_xscom_region_init(&n1_chiplet->xscom_pb_eq_mr, OBJECT(n1_chiplet),
+                          &pnv_n1_chiplet_pb_scom_eq_ops, n1_chiplet,
+                          "xscom-n1-chiplet-pb-scom-eq",
+                          PNV10_XSCOM_N1_PB_SCOM_EQ_SIZE);
+
+    /* Nest1 chiplet power bus ES xscom region */
+    pnv_xscom_region_init(&n1_chiplet->xscom_pb_es_mr, OBJECT(n1_chiplet),
+                          &pnv_n1_chiplet_pb_scom_es_ops, n1_chiplet,
+                          "xscom-n1-chiplet-pb-scom-es",
+                          PNV10_XSCOM_N1_PB_SCOM_ES_SIZE);
+}
+
+static void pnv_n1_chiplet_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->desc = "PowerNV n1 chiplet";
+    dc->realize = pnv_n1_chiplet_realize;
+}
+
+static void pnv_n1_chiplet_instance_init(Object *obj)
+{
+    PnvN1Chiplet *n1_chiplet = PNV_N1_CHIPLET(obj);
+
+    object_initialize_child(OBJECT(n1_chiplet), "nest-pervasive-common",
+                            &n1_chiplet->nest_pervasive,
+                            TYPE_PNV_NEST_CHIPLET_PERVASIVE);
+}
+
+static const TypeInfo pnv_n1_chiplet_info = {
+    .name          = TYPE_PNV_N1_CHIPLET,
+    .parent        = TYPE_DEVICE,
+    .instance_init = pnv_n1_chiplet_instance_init,
+    .instance_size = sizeof(PnvN1Chiplet),
+    .class_init    = pnv_n1_chiplet_class_init,
+    .interfaces    = (InterfaceInfo[]) {
+        { TYPE_PNV_XSCOM_INTERFACE },
+        { }
+    }
+};
+
+static void pnv_n1_chiplet_register_types(void)
+{
+    type_register_static(&pnv_n1_chiplet_info);
+}
+
+type_init(pnv_n1_chiplet_register_types);
diff --git a/hw/ppc/meson.build b/hw/ppc/meson.build
index d6f6f94fcc..256e453c0c 100644
--- a/hw/ppc/meson.build
+++ b/hw/ppc/meson.build
@@ -52,6 +52,7 @@ ppc_ss.add(when: 'CONFIG_POWERNV', if_true: files(
   'pnv_homer.c',
   'pnv_pnor.c',
   'pnv_nest_pervasive.c',
+  'pnv_n1_chiplet.c',
 ))
 # PowerPC 4xx boards
 ppc_ss.add(when: 'CONFIG_PPC405', if_true: files(
-- 
2.31.1

On 12/8/23 16:19, Chalapathi V wrote:
> The N1 chiplet handle the high speed i/o traffic over PCIe and others.
> The N1 chiplet consists of PowerBus Fabric controller,
> nest Memory Management Unit, chiplet control unit and more.
> 
> This commit creates a N1 chiplet model and initialize and realize the
> pervasive chiplet model where chiplet control registers are implemented.
> 
> This commit also implement the read/write method for the powerbus scom
> registers
> 
> Signed-off-by: Chalapathi V <chalapathi.v@linux.ibm.com>


Reviewed-by: Cédric Le Goater <clg@kaod.org>

Thanks,

C.