[PATCH v4 1/3] hw/ppc: Add pnv pervasive common chiplet units

Chalapathi V posted 3 patches 1 year ago
Maintainers: Nicholas Piggin <npiggin@gmail.com>, Daniel Henrique Barboza <danielhb413@gmail.com>, "Cédric Le Goater" <clg@kaod.org>, "Frédéric Barrat" <fbarrat@linux.ibm.com>
There is a newer version of this series
[PATCH v4 1/3] hw/ppc: Add pnv pervasive common chiplet units
Posted by Chalapathi V 1 year ago
From: Chalapathi V <chalapathi.v@linux.ibm.com>

This part of the patchset creates a common pervasive chiplet model where it
houses the common units of a chiplets.

The chiplet control unit is common across chiplets and this commit implements
the pervasive chiplet model with chiplet control registers.

Signed-off-by: Chalapathi V <chalapathi.v@linux.ibm.com>
---
 hw/ppc/meson.build             |   1 +
 hw/ppc/pnv_pervasive.c         | 213 +++++++++++++++++++++++++++++++++++++++++
 include/hw/ppc/pnv_pervasive.h |  39 ++++++++
 include/hw/ppc/pnv_xscom.h     |   3 +
 4 files changed, 256 insertions(+)
 create mode 100644 hw/ppc/pnv_pervasive.c
 create mode 100644 include/hw/ppc/pnv_pervasive.h

diff --git a/hw/ppc/meson.build b/hw/ppc/meson.build
index 7c2c524..c80d2f6 100644
--- a/hw/ppc/meson.build
+++ b/hw/ppc/meson.build
@@ -50,6 +50,7 @@ ppc_ss.add(when: 'CONFIG_POWERNV', if_true: files(
   'pnv_bmc.c',
   'pnv_homer.c',
   'pnv_pnor.c',
+  'pnv_pervasive.c',
 ))
 # PowerPC 4xx boards
 ppc_ss.add(when: 'CONFIG_PPC405', if_true: files(
diff --git a/hw/ppc/pnv_pervasive.c b/hw/ppc/pnv_pervasive.c
new file mode 100644
index 0000000..40f60b5
--- /dev/null
+++ b/hw/ppc/pnv_pervasive.c
@@ -0,0 +1,213 @@
+/*
+ * QEMU PowerPC pervasive common chiplet model
+ *
+ * Copyright (c) 2023, IBM Corporation.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * This code is licensed under the GPL version 2 or later. See the
+ * COPYING file in the top-level directory.
+ */
+
+#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_pervasive.h"
+#include "hw/ppc/fdt.h"
+#include <libfdt.h>
+
+#define CPLT_CONF0               0x08
+#define CPLT_CONF0_OR            0x18
+#define CPLT_CONF0_CLEAR         0x28
+#define CPLT_CONF1               0x09
+#define CPLT_CONF1_OR            0x19
+#define CPLT_CONF1_CLEAR         0x29
+#define CPLT_STAT0               0x100
+#define CPLT_MASK0               0x101
+#define CPLT_PROTECT_MODE        0x3FE
+#define CPLT_ATOMIC_CLOCK        0x3FF
+
+static uint64_t pnv_chiplet_ctrl_read(void *opaque, hwaddr addr,
+                                 unsigned size)
+{
+    PnvPervChiplet *perv_chiplet = PNV_PERVCHIPLET(opaque);
+    int reg = addr >> 3;
+    uint64_t val = ~0ull;
+    /* CPLT_CTRL0 to CPLT_CTRL5 */
+    for (int i = 0; i <= 5; i++) {
+        if (reg == i) {
+            val = perv_chiplet->control_regs.cplt_ctrl[i];
+            return val;
+        } else if ((reg == (i + 0x10)) || (reg == (i + 0x20))) {
+            qemu_log_mask(LOG_GUEST_ERROR, "%s: Write only register, ignoring "
+                                           "xscom read at 0x%" PRIx64 "\n",
+                                           __func__, (unsigned long)reg);
+            return val;
+        }
+    }
+
+    switch (reg) {
+    case CPLT_CONF0:
+        val = perv_chiplet->control_regs.cplt_cfg0;
+        break;
+    case CPLT_CONF0_OR:
+    case CPLT_CONF0_CLEAR:
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: Write only register, ignoring "
+                                   "xscom read at 0x%" PRIx64 "\n",
+                                   __func__, (unsigned long)reg);
+        break;
+    case CPLT_CONF1:
+        val = perv_chiplet->control_regs.cplt_cfg1;
+        break;
+    case CPLT_CONF1_OR:
+    case CPLT_CONF1_CLEAR:
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: Write only register, ignoring "
+                                   "xscom read at 0x%" PRIx64 "\n",
+                                   __func__, (unsigned long)reg);
+        break;
+    case CPLT_STAT0:
+        val = perv_chiplet->control_regs.cplt_stat0;
+        break;
+    case CPLT_MASK0:
+        val = perv_chiplet->control_regs.cplt_mask0;
+        break;
+    case CPLT_PROTECT_MODE:
+        val = perv_chiplet->control_regs.ctrl_protect_mode;
+        break;
+    case CPLT_ATOMIC_CLOCK:
+        val = perv_chiplet->control_regs.ctrl_atomic_lock;
+        break;
+    default:
+        qemu_log_mask(LOG_UNIMP, "%s: Chiplet_control_regs: Invalid xscom "
+                 "read at 0x%" PRIx64 "\n", __func__, (unsigned long)reg);
+    }
+    return val;
+}
+
+static void pnv_chiplet_ctrl_write(void *opaque, hwaddr addr,
+                                 uint64_t val, unsigned size)
+{
+    PnvPervChiplet *perv_chiplet = PNV_PERVCHIPLET(opaque);
+    int reg = addr >> 3;
+    /* CPLT_CTRL0 to CPLT_CTRL5 */
+    for (int i = 0; i <= 5; i++) {
+        if (reg == i) {
+            perv_chiplet->control_regs.cplt_ctrl[i] = val;
+            return;
+        } else if (reg == (i + 0x10)) {
+            perv_chiplet->control_regs.cplt_ctrl[i] |= val;
+            return;
+        } else if (reg == (i + 0x20)) {
+            perv_chiplet->control_regs.cplt_ctrl[i] &= ~val;
+            return;
+        }
+    }
+
+    switch (reg) {
+    case CPLT_CONF0:
+        perv_chiplet->control_regs.cplt_cfg0 = val;
+        break;
+    case CPLT_CONF0_OR:
+        perv_chiplet->control_regs.cplt_cfg0 |= val;
+        break;
+    case CPLT_CONF0_CLEAR:
+        perv_chiplet->control_regs.cplt_cfg0 &= ~val;
+        break;
+    case CPLT_CONF1:
+        perv_chiplet->control_regs.cplt_cfg1 = val;
+        break;
+    case CPLT_CONF1_OR:
+        perv_chiplet->control_regs.cplt_cfg1 |= val;
+        break;
+    case CPLT_CONF1_CLEAR:
+        perv_chiplet->control_regs.cplt_cfg1 &= ~val;
+        break;
+    case CPLT_STAT0:
+        perv_chiplet->control_regs.cplt_stat0 = val;
+        break;
+    case CPLT_MASK0:
+        perv_chiplet->control_regs.cplt_mask0 = val;
+        break;
+    case CPLT_PROTECT_MODE:
+        perv_chiplet->control_regs.ctrl_protect_mode = val;
+        break;
+    case CPLT_ATOMIC_CLOCK:
+        perv_chiplet->control_regs.ctrl_atomic_lock = val;
+        break;
+    default:
+        qemu_log_mask(LOG_UNIMP, "%s: Chiplet_control_regs: Invalid xscom "
+                                 "write at 0x%" PRIx64 "\n",
+                                 __func__, (unsigned long)reg);
+    }
+    return;
+}
+
+static const MemoryRegionOps pnv_perv_chiplet_control_xscom_ops = {
+    .read = pnv_chiplet_ctrl_read,
+    .write = pnv_chiplet_ctrl_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_perv_chiplet_realize(DeviceState *dev, Error **errp)
+{
+    PnvPervChiplet *perv_chiplet = PNV_PERVCHIPLET(dev);
+
+    /* Chiplet control scoms */
+    pnv_xscom_region_init(&perv_chiplet->xscom_perv_ctrl_regs,
+                          OBJECT(perv_chiplet),
+                          &pnv_perv_chiplet_control_xscom_ops,
+                          perv_chiplet, "xscom-chiplet-control-regs",
+                          PNV10_XSCOM_CTRL_CHIPLET_SIZE);
+}
+
+void pnv_perv_dt(uint32_t base_addr, void *fdt,
+                             int offset)
+{
+    g_autofree char *name = NULL;
+    int perv_chiplet_offset;
+
+    const char compat[] = "ibm,power10-perv-chiplet";
+    uint32_t reg[] = {
+        base_addr,
+        cpu_to_be32(PNV10_XSCOM_CTRL_CHIPLET_SIZE)
+    };
+    name = g_strdup_printf("perv_chiplet@%x", base_addr);
+    perv_chiplet_offset = fdt_add_subnode(fdt, offset, name);
+    _FDT(perv_chiplet_offset);
+
+    _FDT(fdt_setprop(fdt, perv_chiplet_offset, "reg", reg, sizeof(reg)));
+    _FDT(fdt_setprop(fdt, perv_chiplet_offset, "compatible",
+                     compat, sizeof(compat)));
+}
+
+static void pnv_perv_chiplet_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->desc = "PowerNV perv chiplet";
+    dc->realize = pnv_perv_chiplet_realize;
+}
+
+static const TypeInfo pnv_perv_chiplet_info = {
+    .name          = TYPE_PNV_PERV_CHIPLET,
+    .parent        = TYPE_DEVICE,
+    .instance_size = sizeof(PnvPervChiplet),
+    .class_init    = pnv_perv_chiplet_class_init,
+    .interfaces    = (InterfaceInfo[]) {
+        { TYPE_PNV_XSCOM_INTERFACE },
+        { }
+    }
+};
+
+static void pnv_perv_chiplet_register_types(void)
+{
+    type_register_static(&pnv_perv_chiplet_info);
+}
+
+type_init(pnv_perv_chiplet_register_types);
diff --git a/include/hw/ppc/pnv_pervasive.h b/include/hw/ppc/pnv_pervasive.h
new file mode 100644
index 0000000..61be4cf
--- /dev/null
+++ b/include/hw/ppc/pnv_pervasive.h
@@ -0,0 +1,39 @@
+/*
+ * QEMU PowerPC pervasive common chiplet model
+ *
+ * Copyright (c) 2023, IBM Corporation.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ *
+ * This code is licensed under the GPL version 2 or later. See the
+ * COPYING file in the top-level directory.
+ */
+
+#ifndef PPC_PNV_PERVASIVE_H
+#define PPC_PNV_PERVASIVE_H
+
+#define TYPE_PNV_PERV_CHIPLET "pnv-pervasive-chiplet"
+#define PNV_PERVCHIPLET(obj) OBJECT_CHECK(PnvPervChiplet, (obj), TYPE_PNV_PERV_CHIPLET)
+
+typedef struct ControlRegs {
+
+    uint64_t cplt_ctrl[6];
+    uint64_t cplt_cfg0;
+    uint64_t cplt_cfg1;
+    uint64_t cplt_stat0;
+    uint64_t cplt_mask0;
+    uint64_t ctrl_protect_mode;
+    uint64_t ctrl_atomic_lock;
+} ControlRegs;
+
+typedef struct PnvPervChiplet {
+
+    DeviceState parent;
+    struct PnvChip *chip;
+    MemoryRegion xscom_perv_ctrl_regs;
+    ControlRegs control_regs;
+
+} PnvPervChiplet;
+
+void pnv_perv_dt(uint32_t base, void *fdt, int offset);
+#endif /*PPC_PNV_PERVASIVE_H */
diff --git a/include/hw/ppc/pnv_xscom.h b/include/hw/ppc/pnv_xscom.h
index 35b1961..87bbee8 100644
--- a/include/hw/ppc/pnv_xscom.h
+++ b/include/hw/ppc/pnv_xscom.h
@@ -164,6 +164,9 @@ struct PnvXScomInterfaceClass {
 #define PNV10_XSCOM_XIVE2_BASE     0x2010800
 #define PNV10_XSCOM_XIVE2_SIZE     0x400
 
+#define PNV10_XSCOM_NEST1_CTRL_CHIPLET_BASE      0x3000000
+#define PNV10_XSCOM_CTRL_CHIPLET_SIZE            0x400
+
 #define PNV10_XSCOM_PEC_NEST_BASE  0x3011800 /* index goes downwards ... */
 #define PNV10_XSCOM_PEC_NEST_SIZE  0x100
 
-- 
1.8.3.1
Re: [PATCH v4 1/3] hw/ppc: Add pnv pervasive common chiplet units
Posted by Cédric Le Goater 1 year ago
Hello Chalapathi,

Please add to your ~/.gitconfig :

   [diff]
	  orderFile = /path/to/qemu/scripts/git.orderfile

It will order the header file first in the patch.

On 11/7/23 08:41, Chalapathi V wrote:
> From: Chalapathi V <chalapathi.v@linux.ibm.com>
> 
> This part of the patchset creates a common pervasive chiplet model where it
> houses the common units of a chiplets.
> 
> The chiplet control unit is common across chiplets and this commit implements
> the pervasive chiplet model with chiplet control registers.
> 
> Signed-off-by: Chalapathi V <chalapathi.v@linux.ibm.com>
> ---
>   hw/ppc/meson.build             |   1 +
>   hw/ppc/pnv_pervasive.c         | 213 +++++++++++++++++++++++++++++++++++++++++
>   include/hw/ppc/pnv_pervasive.h |  39 ++++++++
>   include/hw/ppc/pnv_xscom.h     |   3 +
>   4 files changed, 256 insertions(+)
>   create mode 100644 hw/ppc/pnv_pervasive.c
>   create mode 100644 include/hw/ppc/pnv_pervasive.h
> 
> diff --git a/hw/ppc/meson.build b/hw/ppc/meson.build
> index 7c2c524..c80d2f6 100644
> --- a/hw/ppc/meson.build
> +++ b/hw/ppc/meson.build
> @@ -50,6 +50,7 @@ ppc_ss.add(when: 'CONFIG_POWERNV', if_true: files(
>     'pnv_bmc.c',
>     'pnv_homer.c',
>     'pnv_pnor.c',
> +  'pnv_pervasive.c',
>   ))
>   # PowerPC 4xx boards
>   ppc_ss.add(when: 'CONFIG_PPC405', if_true: files(
> diff --git a/hw/ppc/pnv_pervasive.c b/hw/ppc/pnv_pervasive.c
> new file mode 100644
> index 0000000..40f60b5
> --- /dev/null
> +++ b/hw/ppc/pnv_pervasive.c
> @@ -0,0 +1,213 @@
> +/*
> + * QEMU PowerPC pervasive common chiplet model
> + *
> + * Copyright (c) 2023, IBM Corporation.
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + *
> + * This code is licensed under the GPL version 2 or later. See the
> + * COPYING file in the top-level directory.
> + */
> +
> +#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_pervasive.h"
> +#include "hw/ppc/fdt.h"
> +#include <libfdt.h>
> +
> +#define CPLT_CONF0               0x08
> +#define CPLT_CONF0_OR            0x18
> +#define CPLT_CONF0_CLEAR         0x28
> +#define CPLT_CONF1               0x09
> +#define CPLT_CONF1_OR            0x19
> +#define CPLT_CONF1_CLEAR         0x29
> +#define CPLT_STAT0               0x100
> +#define CPLT_MASK0               0x101
> +#define CPLT_PROTECT_MODE        0x3FE
> +#define CPLT_ATOMIC_CLOCK        0x3FF
> +
> +static uint64_t pnv_chiplet_ctrl_read(void *opaque, hwaddr addr,
> +                                 unsigned size)
> +{
> +    PnvPervChiplet *perv_chiplet = PNV_PERVCHIPLET(opaque);
> +    int reg = addr >> 3;
> +    uint64_t val = ~0ull;

White line please

> +    /* CPLT_CTRL0 to CPLT_CTRL5 */
> +    for (int i = 0; i <= 5; i++) {

I would introduce a #define for this "5" value, and use it in ControlRegs also.

> +        if (reg == i) {
> +            val = perv_chiplet->control_regs.cplt_ctrl[i];
> +            return val;

or may be :

        return perv_chiplet->control_regs.cplt_ctrl[i];  ?
  

> +        } else if ((reg == (i + 0x10)) || (reg == (i + 0x20))) {
> +            qemu_log_mask(LOG_GUEST_ERROR, "%s: Write only register, ignoring "
> +                                           "xscom read at 0x%" PRIx64 "\n",
> +                                           __func__, (unsigned long)reg);
> +            return val;
> +        }
> +    }
> +
> +    switch (reg) {
> +    case CPLT_CONF0:
> +        val = perv_chiplet->control_regs.cplt_cfg0;
> +        break;
> +    case CPLT_CONF0_OR:
> +    case CPLT_CONF0_CLEAR:
> +        qemu_log_mask(LOG_GUEST_ERROR, "%s: Write only register, ignoring "
> +                                   "xscom read at 0x%" PRIx64 "\n",
> +                                   __func__, (unsigned long)reg);
> +        break;
> +    case CPLT_CONF1:
> +        val = perv_chiplet->control_regs.cplt_cfg1;
> +        break;
> +    case CPLT_CONF1_OR:
> +    case CPLT_CONF1_CLEAR:
> +        qemu_log_mask(LOG_GUEST_ERROR, "%s: Write only register, ignoring "
> +                                   "xscom read at 0x%" PRIx64 "\n",
> +                                   __func__, (unsigned long)reg);
> +        break;
> +    case CPLT_STAT0:
> +        val = perv_chiplet->control_regs.cplt_stat0;
> +        break;
> +    case CPLT_MASK0:
> +        val = perv_chiplet->control_regs.cplt_mask0;
> +        break;
> +    case CPLT_PROTECT_MODE:
> +        val = perv_chiplet->control_regs.ctrl_protect_mode;
> +        break;
> +    case CPLT_ATOMIC_CLOCK:
> +        val = perv_chiplet->control_regs.ctrl_atomic_lock;
> +        break;
> +    default:
> +        qemu_log_mask(LOG_UNIMP, "%s: Chiplet_control_regs: Invalid xscom "
> +                 "read at 0x%" PRIx64 "\n", __func__, (unsigned long)reg);
> +    }
> +    return val;
> +}
> +
> +static void pnv_chiplet_ctrl_write(void *opaque, hwaddr addr,
> +                                 uint64_t val, unsigned size)
> +{
> +    PnvPervChiplet *perv_chiplet = PNV_PERVCHIPLET(opaque);
> +    int reg = addr >> 3;
> +    /* CPLT_CTRL0 to CPLT_CTRL5 */
> +    for (int i = 0; i <= 5; i++) {
> +        if (reg == i) {
> +            perv_chiplet->control_regs.cplt_ctrl[i] = val;
> +            return;
> +        } else if (reg == (i + 0x10)) {
> +            perv_chiplet->control_regs.cplt_ctrl[i] |= val;
> +            return;
> +        } else if (reg == (i + 0x20)) {
> +            perv_chiplet->control_regs.cplt_ctrl[i] &= ~val;
> +            return;
> +        }
> +    }
> +
> +    switch (reg) {
> +    case CPLT_CONF0:
> +        perv_chiplet->control_regs.cplt_cfg0 = val;
> +        break;
> +    case CPLT_CONF0_OR:
> +        perv_chiplet->control_regs.cplt_cfg0 |= val;
> +        break;
> +    case CPLT_CONF0_CLEAR:
> +        perv_chiplet->control_regs.cplt_cfg0 &= ~val;
> +        break;
> +    case CPLT_CONF1:
> +        perv_chiplet->control_regs.cplt_cfg1 = val;
> +        break;
> +    case CPLT_CONF1_OR:
> +        perv_chiplet->control_regs.cplt_cfg1 |= val;
> +        break;
> +    case CPLT_CONF1_CLEAR:
> +        perv_chiplet->control_regs.cplt_cfg1 &= ~val;
> +        break;
> +    case CPLT_STAT0:
> +        perv_chiplet->control_regs.cplt_stat0 = val;
> +        break;
> +    case CPLT_MASK0:
> +        perv_chiplet->control_regs.cplt_mask0 = val;
> +        break;
> +    case CPLT_PROTECT_MODE:
> +        perv_chiplet->control_regs.ctrl_protect_mode = val;
> +        break;
> +    case CPLT_ATOMIC_CLOCK:
> +        perv_chiplet->control_regs.ctrl_atomic_lock = val;
> +        break;
> +    default:
> +        qemu_log_mask(LOG_UNIMP, "%s: Chiplet_control_regs: Invalid xscom "
> +                                 "write at 0x%" PRIx64 "\n",
> +                                 __func__, (unsigned long)reg);
> +    }
> +    return;

This return is useless.

> +}
> +
> +static const MemoryRegionOps pnv_perv_chiplet_control_xscom_ops = {
> +    .read = pnv_chiplet_ctrl_read,
> +    .write = pnv_chiplet_ctrl_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_perv_chiplet_realize(DeviceState *dev, Error **errp)
> +{
> +    PnvPervChiplet *perv_chiplet = PNV_PERVCHIPLET(dev);
> +
> +    /* Chiplet control scoms */
> +    pnv_xscom_region_init(&perv_chiplet->xscom_perv_ctrl_regs,
> +                          OBJECT(perv_chiplet),
> +                          &pnv_perv_chiplet_control_xscom_ops,
> +                          perv_chiplet, "xscom-chiplet-control-regs",
> +                          PNV10_XSCOM_CTRL_CHIPLET_SIZE);
> +}
> +
> +void pnv_perv_dt(uint32_t base_addr, void *fdt,
> +                             int offset)
> +{
> +    g_autofree char *name = NULL;
> +    int perv_chiplet_offset;
> +
> +    const char compat[] = "ibm,power10-perv-chiplet";
> +    uint32_t reg[] = {
> +        base_addr,
> +        cpu_to_be32(PNV10_XSCOM_CTRL_CHIPLET_SIZE)
> +    };
> +    name = g_strdup_printf("perv_chiplet@%x", base_addr);
> +    perv_chiplet_offset = fdt_add_subnode(fdt, offset, name);
> +    _FDT(perv_chiplet_offset);
> +
> +    _FDT(fdt_setprop(fdt, perv_chiplet_offset, "reg", reg, sizeof(reg)));
> +    _FDT(fdt_setprop(fdt, perv_chiplet_offset, "compatible",
> +                     compat, sizeof(compat)));
> +}
> +
> +static void pnv_perv_chiplet_class_init(ObjectClass *klass, void *data)
> +{
> +    DeviceClass *dc = DEVICE_CLASS(klass);
> +
> +    dc->desc = "PowerNV perv chiplet";
> +    dc->realize = pnv_perv_chiplet_realize;
> +}
> +
> +static const TypeInfo pnv_perv_chiplet_info = {
> +    .name          = TYPE_PNV_PERV_CHIPLET,
> +    .parent        = TYPE_DEVICE,
> +    .instance_size = sizeof(PnvPervChiplet),
> +    .class_init    = pnv_perv_chiplet_class_init,
> +    .interfaces    = (InterfaceInfo[]) {
> +        { TYPE_PNV_XSCOM_INTERFACE },
> +        { }
> +    }
> +};
> +
> +static void pnv_perv_chiplet_register_types(void)
> +{
> +    type_register_static(&pnv_perv_chiplet_info);
> +}
> +
> +type_init(pnv_perv_chiplet_register_types);
> diff --git a/include/hw/ppc/pnv_pervasive.h b/include/hw/ppc/pnv_pervasive.h
> new file mode 100644
> index 0000000..61be4cf
> --- /dev/null
> +++ b/include/hw/ppc/pnv_pervasive.h
> @@ -0,0 +1,39 @@
> +/*
> + * QEMU PowerPC pervasive common chiplet model
> + *
> + * Copyright (c) 2023, IBM Corporation.
> + *
> + * SPDX-License-Identifier: GPL-2.0-or-later
> + *
> + * This code is licensed under the GPL version 2 or later. See the
> + * COPYING file in the top-level directory.
> + */
> +
> +#ifndef PPC_PNV_PERVASIVE_H
> +#define PPC_PNV_PERVASIVE_H
> +
> +#define TYPE_PNV_PERV_CHIPLET "pnv-pervasive-chiplet"
> +#define PNV_PERVCHIPLET(obj) OBJECT_CHECK(PnvPervChiplet, (obj), TYPE_PNV_PERV_CHIPLET)
> +
> +typedef struct ControlRegs {

This needs some prefix : PnvPervChipletRegs ?

> +

Please remove the extra white line.
  
> +    uint64_t cplt_ctrl[6];

Introduce a #define since you need it in the memops.

> +    uint64_t cplt_cfg0;
> +    uint64_t cplt_cfg1;
> +    uint64_t cplt_stat0;
> +    uint64_t cplt_mask0;
> +    uint64_t ctrl_protect_mode;
> +    uint64_t ctrl_atomic_lock;
> +} ControlRegs;
> +
> +typedef struct PnvPervChiplet {
> +
> +    DeviceState parent;
> +    struct PnvChip *chip;

chip is unused, please remove.

> +    MemoryRegion xscom_perv_ctrl_regs;
> +    ControlRegs control_regs;
> +

Drop white line.


> +} PnvPervChiplet;
> +
> +void pnv_perv_dt(uint32_t base, void *fdt, int offset);
> +#endif /*PPC_PNV_PERVASIVE_H */
> diff --git a/include/hw/ppc/pnv_xscom.h b/include/hw/ppc/pnv_xscom.h
> index 35b1961..87bbee8 100644
> --- a/include/hw/ppc/pnv_xscom.h
> +++ b/include/hw/ppc/pnv_xscom.h
> @@ -164,6 +164,9 @@ struct PnvXScomInterfaceClass {
>   #define PNV10_XSCOM_XIVE2_BASE     0x2010800
>   #define PNV10_XSCOM_XIVE2_SIZE     0x400
>   
> +#define PNV10_XSCOM_NEST1_CTRL_CHIPLET_BASE      0x3000000
> +#define PNV10_XSCOM_CTRL_CHIPLET_SIZE            0x400
> +
>   #define PNV10_XSCOM_PEC_NEST_BASE  0x3011800 /* index goes downwards ... */
>   #define PNV10_XSCOM_PEC_NEST_SIZE  0x100
>