ppc/pnv: Begin a more complete ADU LPC model for POWER9/10

This implements a framework for an ADU unit model.

The ADU unit actually implements XSCOM, which is the bridge between MMIO
and PIB. However it also includes control and status registers and other
functions that are exposed as PIB (xscom) registers.

To keep things simple, pnv_xscom.c remains the XSCOM bridge
implementation, and pnv_adu.c implements the ADU registers and other
functions.

So far, just the ADU no-op registers in the pnv_xscom.c default handler
are moved over to the adu model.

Reviewed-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>

5 files changed, 132 insertions, 9 deletions

diff --git a/hw/ppc/meson.build b/hw/ppc/meson.build
index 3ebbf329bc..7cd9189869 100644
--- a/hw/ppc/meson.build
+++ b/hw/ppc/meson.build
@@ -42,6 +42,7 @@ endif
 ppc_ss.add(when: 'CONFIG_POWERNV', if_true: files(
   'pnv.c',
   'pnv_xscom.c',
+  'pnv_adu.c',
   'pnv_core.c',
   'pnv_i2c.c',
   'pnv_lpc.c',
diff --git a/hw/ppc/pnv.c b/hw/ppc/pnv.c
index f56dcf6597..689197cbb7 100644
--- a/hw/ppc/pnv.c
+++ b/hw/ppc/pnv.c
@@ -1551,6 +1551,7 @@ static void pnv_chip_power9_instance_init(Object *obj)
     PnvChipClass *pcc = PNV_CHIP_GET_CLASS(obj);
     int i;
 
+    object_initialize_child(obj, "adu",  &chip9->adu, TYPE_PNV_ADU);
     object_initialize_child(obj, "xive", &chip9->xive, TYPE_PNV_XIVE);
     object_property_add_alias(obj, "xive-fabric", OBJECT(&chip9->xive),
                               "xive-fabric");
@@ -1661,6 +1662,13 @@ static void pnv_chip_power9_realize(DeviceState *dev, Error **errp)
         return;
     }
 
+    /* ADU */
+    if (!qdev_realize(DEVICE(&chip9->adu), NULL, errp)) {
+        return;
+    }
+    pnv_xscom_add_subregion(chip, PNV9_XSCOM_ADU_BASE,
+                            &chip9->adu.xscom_regs);
+
     pnv_chip_quad_realize(chip9, &local_err);
     if (local_err) {
         error_propagate(errp, local_err);
@@ -1827,6 +1835,7 @@ static void pnv_chip_power10_instance_init(Object *obj)
     PnvChipClass *pcc = PNV_CHIP_GET_CLASS(obj);
     int i;
 
+    object_initialize_child(obj, "adu",  &chip10->adu, TYPE_PNV_ADU);
     object_initialize_child(obj, "xive", &chip10->xive, TYPE_PNV_XIVE2);
     object_property_add_alias(obj, "xive-fabric", OBJECT(&chip10->xive),
                               "xive-fabric");
@@ -1919,6 +1928,13 @@ static void pnv_chip_power10_realize(DeviceState *dev, Error **errp)
         return;
     }
 
+    /* ADU */
+    if (!qdev_realize(DEVICE(&chip10->adu), NULL, errp)) {
+        return;
+    }
+    pnv_xscom_add_subregion(chip, PNV10_XSCOM_ADU_BASE,
+                            &chip10->adu.xscom_regs);
+
     pnv_chip_power10_quad_realize(chip10, &local_err);
     if (local_err) {
         error_propagate(errp, local_err);
diff --git a/hw/ppc/pnv_adu.c b/hw/ppc/pnv_adu.c
new file mode 100644
index 0000000000..8279bc8b26
--- /dev/null
+++ b/hw/ppc/pnv_adu.c
@@ -0,0 +1,111 @@
+/*
+ * QEMU PowerPC PowerNV ADU unit
+ *
+ * The ADU unit actually implements XSCOM, which is the bridge between MMIO
+ * and PIB. However it also includes control and status registers and other
+ * functions that are exposed as PIB (xscom) registers.
+ *
+ * To keep things simple, pnv_xscom.c remains the XSCOM bridge
+ * implementation, and pnv_adu.c implements the ADU registers and other
+ * functions.
+ *
+ * Copyright (c) 2024, 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_adu.h"
+#include "hw/ppc/pnv_chip.h"
+#include "hw/ppc/pnv_xscom.h"
+#include "trace.h"
+
+static uint64_t pnv_adu_xscom_read(void *opaque, hwaddr addr, unsigned width)
+{
+    uint32_t offset = addr >> 3;
+    uint64_t val = 0;
+
+    switch (offset) {
+    case 0x18:     /* Receive status reg */
+    case 0x12:     /* log register */
+    case 0x13:     /* error register */
+        break;
+
+    default:
+        qemu_log_mask(LOG_UNIMP, "ADU Unimplemented read register: Ox%08x\n",
+                                                                     offset);
+    }
+
+    trace_pnv_adu_xscom_read(addr, val);
+
+    return val;
+}
+
+static void pnv_adu_xscom_write(void *opaque, hwaddr addr, uint64_t val,
+                                unsigned width)
+{
+    uint32_t offset = addr >> 3;
+
+    trace_pnv_adu_xscom_write(addr, val);
+
+    switch (offset) {
+    case 0x18:     /* Receive status reg */
+    case 0x12:     /* log register */
+    case 0x13:     /* error register */
+        break;
+
+    default:
+        qemu_log_mask(LOG_UNIMP, "ADU Unimplemented write register: Ox%08x\n",
+                                                                     offset);
+    }
+}
+
+const MemoryRegionOps pnv_adu_xscom_ops = {
+    .read = pnv_adu_xscom_read,
+    .write = pnv_adu_xscom_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_adu_realize(DeviceState *dev, Error **errp)
+{
+    PnvADU *adu = PNV_ADU(dev);
+
+    /* XScom regions for ADU registers */
+    pnv_xscom_region_init(&adu->xscom_regs, OBJECT(dev),
+                          &pnv_adu_xscom_ops, adu, "xscom-adu",
+                          PNV9_XSCOM_ADU_SIZE);
+}
+
+static void pnv_adu_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    dc->realize = pnv_adu_realize;
+    dc->desc = "PowerNV ADU";
+    dc->user_creatable = false;
+}
+
+static const TypeInfo pnv_adu_type_info = {
+    .name          = TYPE_PNV_ADU,
+    .parent        = TYPE_DEVICE,
+    .instance_size = sizeof(PnvADU),
+    .class_init    = pnv_adu_class_init,
+    .interfaces    = (InterfaceInfo[]) {
+        { TYPE_PNV_XSCOM_INTERFACE },
+        { } },
+};
+
+static void pnv_adu_register_types(void)
+{
+    type_register_static(&pnv_adu_type_info);
+}
+
+type_init(pnv_adu_register_types);
diff --git a/hw/ppc/pnv_xscom.c b/hw/ppc/pnv_xscom.c
index a17816d072..d192bbe2c2 100644
--- a/hw/ppc/pnv_xscom.c
+++ b/hw/ppc/pnv_xscom.c
@@ -75,11 +75,6 @@ static uint64_t xscom_read_default(PnvChip *chip, uint32_t pcba)
     case PRD_P9_IPOLL_REG_MASK:
     case PRD_P9_IPOLL_REG_STATUS:
 
-        /* P9 xscom reset */
-    case 0x0090018:     /* Receive status reg */
-    case 0x0090012:     /* log register */
-    case 0x0090013:     /* error register */
-
         /* P8 xscom reset */
     case 0x2020007:     /* ADU stuff, log register */
     case 0x2020009:     /* ADU stuff, error register */
@@ -119,10 +114,6 @@ static bool xscom_write_default(PnvChip *chip, uint32_t pcba, uint64_t val)
     case 0x1010c03:     /* PIBAM FIR MASK */
     case 0x1010c04:     /* PIBAM FIR MASK */
     case 0x1010c05:     /* PIBAM FIR MASK */
-        /* P9 xscom reset */
-    case 0x0090018:     /* Receive status reg */
-    case 0x0090012:     /* log register */
-    case 0x0090013:     /* error register */
 
         /* P8 xscom reset */
     case 0x2020007:     /* ADU stuff, log register */
diff --git a/hw/ppc/trace-events b/hw/ppc/trace-events
index bf29bbfd4b..1f125ce841 100644
--- a/hw/ppc/trace-events
+++ b/hw/ppc/trace-events
@@ -95,6 +95,10 @@ vof_write(uint32_t ih, unsigned cb, const char *msg) "ih=0x%x [%u] \"%s\""
 vof_avail(uint64_t start, uint64_t end, uint64_t size) "0x%"PRIx64"..0x%"PRIx64" size=0x%"PRIx64
 vof_claimed(uint64_t start, uint64_t end, uint64_t size) "0x%"PRIx64"..0x%"PRIx64" size=0x%"PRIx64
 
+# pnv_adu.c
+pnv_adu_xscom_read(uint64_t addr, uint64_t val) "addr 0x%" PRIx64 " val 0x%" PRIx64
+pnv_adu_xscom_write(uint64_t addr, uint64_t val) "addr 0x%" PRIx64 " val 0x%" PRIx64
+
 # pnv_chiptod.c
 pnv_chiptod_xscom_read(uint64_t addr, uint64_t val) "addr 0x%" PRIx64 " val 0x%" PRIx64
 pnv_chiptod_xscom_write(uint64_t addr, uint64_t val) "addr 0x%" PRIx64 " val 0x%" PRIx64