Re: [PATCH v1 1/7] hw/fsi: Introduce IBM's Local bus

[Ninad Palsule <ninad@linux.ibm.com>]

Hi Joel,

On 8/28/23 23:34, Joel Stanley wrote:
> On Fri, 25 Aug 2023 at 20:31, Ninad Palsule <ninad@linux.ibm.com> wrote:
>> This is a part of patchset where IBM's Flexible Service Interface is
>> introduced.
>>
>> The LBUS is modelled to maintain the qdev bus hierarchy and to take
>> advantage of the object model to automatically generate the CFAM
>> configuration block. The configuration block presents engines in the
>> order they are attached to the CFAM's LBUS. Engine implementations
>> should subclass the LBusDevice and set the 'config' member of
>> LBusDeviceClass to match the engine's type.
>>
>> Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
>> Signed-off-by: Cédric Le Goater <clg@kaod.org>
>> Signed-off-by: Ninad Palsule <ninad@linux.ibm.com>
>> ---
>>   hw/Kconfig            |  1 +
>>   hw/fsi/Kconfig        |  2 +
>>   hw/fsi/lbus.c         | 94 +++++++++++++++++++++++++++++++++++++++++++
>>   hw/fsi/meson.build    |  1 +
>>   hw/meson.build        |  1 +
>>   include/hw/fsi/bits.h | 15 +++++++
>>   include/hw/fsi/lbus.h | 57 ++++++++++++++++++++++++++
>>   7 files changed, 171 insertions(+)
>>   create mode 100644 hw/fsi/Kconfig
>>   create mode 100644 hw/fsi/lbus.c
>>   create mode 100644 hw/fsi/meson.build
>>   create mode 100644 include/hw/fsi/bits.h
>>   create mode 100644 include/hw/fsi/lbus.h
>>
>> diff --git a/hw/Kconfig b/hw/Kconfig
>> index ba62ff6417..2ccb73add5 100644
>> --- a/hw/Kconfig
>> +++ b/hw/Kconfig
>> @@ -9,6 +9,7 @@ source core/Kconfig
>>   source cxl/Kconfig
>>   source display/Kconfig
>>   source dma/Kconfig
>> +source fsi/Kconfig
>>   source gpio/Kconfig
>>   source hyperv/Kconfig
>>   source i2c/Kconfig
>> diff --git a/hw/fsi/Kconfig b/hw/fsi/Kconfig
>> new file mode 100644
>> index 0000000000..687449e14e
>> --- /dev/null
>> +++ b/hw/fsi/Kconfig
>> @@ -0,0 +1,2 @@
>> +config LBUS
>> +    bool
>> diff --git a/hw/fsi/lbus.c b/hw/fsi/lbus.c
>> new file mode 100644
>> index 0000000000..afb26ef7ea
>> --- /dev/null
>> +++ b/hw/fsi/lbus.c
>> @@ -0,0 +1,94 @@
>> +/*
>> + * SPDX-License-Identifier: GPL-2.0-or-later
>> + * Copyright (C) 2023 IBM Corp.
>> + *
>> + * IBM Local bus where FSI slaves are connected
>> + */
>> +
>> +#include "qemu/osdep.h"
>> +
>> +#include "qapi/error.h"
>> +#include "qemu/log.h"
>> +
>> +#include "hw/fsi/lbus.h"
>> +
>> +#include "hw/qdev-properties.h"
>> +
>> +static void lbus_realize(BusState *bus, Error **errp)
>> +{
>> +    LBusNode *node;
>> +    LBus *lbus = LBUS(bus);
>> +
>> +    memory_region_init(&lbus->mr, OBJECT(lbus), TYPE_LBUS,
>> +                       (2 * 1024 * 1024) - 0x400);
>> +
>> +    QLIST_FOREACH(node, &lbus->devices, next) {
>> +        memory_region_add_subregion(&lbus->mr, node->ldev->address,
>> +                                    &node->ldev->iomem);
>> +    }
>> +}
>> +
>> +static void lbus_init(Object *o)
>> +{
>> +}
>> +
>> +static void lbus_class_init(ObjectClass *klass, void *data)
>> +{
>> +    BusClass *k = BUS_CLASS(klass);
>> +    k->realize = lbus_realize;
>> +}
>> +
>> +static const TypeInfo lbus_info = {
>> +    .name = TYPE_LBUS,
>> +    .parent = TYPE_BUS,
>> +    .instance_init = lbus_init,
>> +    .instance_size = sizeof(LBus),
>> +    .class_init = lbus_class_init,
>> +};
>> +
>> +static Property lbus_device_props[] = {
>> +    DEFINE_PROP_UINT32("address", LBusDevice, address, 0),
>> +    DEFINE_PROP_END_OF_LIST(),
>> +};
>> +
>> +DeviceState *lbus_create_device(LBus *bus, const char *type, uint32_t addr)
>> +{
>> +    DeviceState *dev;
>> +    LBusNode *node;
>> +
>> +    dev = qdev_new(type);
>> +    qdev_prop_set_uint8(dev, "address", addr);
>> +    qdev_realize_and_unref(dev, &bus->bus, &error_fatal);
>> +
>> +    /* Move to post_load */
>> +    node = g_malloc(sizeof(struct LBusNode));
>> +    node->ldev = LBUS_DEVICE(dev);
>> +    QLIST_INSERT_HEAD(&bus->devices, node, next);
>> +
>> +    return dev;
>> +}
>> +
>> +static void lbus_device_class_init(ObjectClass *klass, void *data)
>> +{
>> +    DeviceClass *dc = DEVICE_CLASS(klass);
>> +
>> +    dc->bus_type = TYPE_LBUS;
>> +    device_class_set_props(dc, lbus_device_props);
>> +}
>> +
>> +static const TypeInfo lbus_device_type_info = {
>> +    .name = TYPE_LBUS_DEVICE,
>> +    .parent = TYPE_DEVICE,
>> +    .instance_size = sizeof(LBusDevice),
>> +    .abstract = true,
>> +    .class_init = lbus_device_class_init,
>> +    .class_size = sizeof(LBusDeviceClass),
>> +};
>> +
>> +static void lbus_register_types(void)
>> +{
>> +    type_register_static(&lbus_info);
>> +    type_register_static(&lbus_device_type_info);
>> +}
>> +
>> +type_init(lbus_register_types);
>> diff --git a/hw/fsi/meson.build b/hw/fsi/meson.build
>> new file mode 100644
>> index 0000000000..e1007d5fea
>> --- /dev/null
>> +++ b/hw/fsi/meson.build
>> @@ -0,0 +1 @@
>> +system_ss.add(when: 'CONFIG_LBUS', if_true: files('lbus.c'))
>> diff --git a/hw/meson.build b/hw/meson.build
>> index c7ac7d3d75..6c71ee9cfa 100644
>> --- a/hw/meson.build
>> +++ b/hw/meson.build
>> @@ -43,6 +43,7 @@ subdir('virtio')
>>   subdir('watchdog')
>>   subdir('xen')
>>   subdir('xenpv')
>> +subdir('fsi')
>>
>>   subdir('alpha')
>>   subdir('arm')
>> diff --git a/include/hw/fsi/bits.h b/include/hw/fsi/bits.h
>> new file mode 100644
>> index 0000000000..338ae483cf
>> --- /dev/null
>> +++ b/include/hw/fsi/bits.h
>> @@ -0,0 +1,15 @@
>> +/*
>> + * SPDX-License-Identifier: GPL-2.0-or-later
>> + * Copyright (C) 2023 IBM Corp.
>> + *
>> + * Bit operation macros
>> + */
>> +#ifndef FSI_BITS_H
>> +#define FSI_BITS_H
>> +
>> +#define BE_BIT(x)                          BIT(31 - (x))
>> +#define GENMASK(t, b) \
>> +    (((1ULL << ((t) + 1)) - 1) & ~((1ULL << (b)) - 1))
>> +#define BE_GENMASK(t, b)                   GENMASK(BE_BIT(t), BE_BIT(b))
> These are similar to the PPC_BIT definitions. We have a copy of them
> in taget/ppc/cpu.h, perhaps they could be moved into a common header.
Moved it to bitopts.h and removed a bits.h file.
>
>> +
>> +#endif /* FSI_BITS_H */
>> diff --git a/include/hw/fsi/lbus.h b/include/hw/fsi/lbus.h
>> new file mode 100644
>> index 0000000000..00ed7e5250
>> --- /dev/null
>> +++ b/include/hw/fsi/lbus.h
>> @@ -0,0 +1,57 @@
>> +/*
>> + * SPDX-License-Identifier: GPL-2.0-or-later
>> + * Copyright (C) 2023 IBM Corp.
>> + *
>> + * IBM Local bus and connected device structures.
>> + */
>> +#ifndef FSI_LBUS_H
>> +#define FSI_LBUS_H
>> +
>> +#include "exec/memory.h"
>> +#include "hw/qdev-core.h"
>> +
>> +#define TYPE_LBUS_DEVICE "lbus.device"
>> +#define LBUS_DEVICE(obj) \
>> +    OBJECT_CHECK(LBusDevice, (obj), TYPE_LBUS_DEVICE)
>> +#define LBUS_DEVICE_CLASS(klass) \
>> +    OBJECT_CLASS_CHECK(LBusDeviceClass, (klass), TYPE_LBUS_DEVICE)
>> +#define LBUS_DEVICE_GET_CLASS(obj) \
>> +    OBJECT_GET_CLASS(LBusDeviceClass, (obj), TYPE_LBUS_DEVICE)
> I think we can use OBJECT_DECLARE_SIMPLE_TYPE here to create the macros for us.
Changed it various places.
>
>> +
>> +typedef struct LBusDevice {
>> +    DeviceState parent;
>> +
>> +    MemoryRegion iomem;
>> +    uint32_t address;
>> +} LBusDevice;
>> +
>> +typedef struct LBusDeviceClass {
>> +    DeviceClass parent;
>> +
>> +    uint32_t config;
>> +} LBusDeviceClass;
>> +
>> +typedef struct LBusNode {
>> +    LBusDevice *ldev;
>> +
>> +    QLIST_ENTRY(LBusNode) next;
>> +} LBusNode;
>> +
>> +#define TYPE_LBUS "lbus"
>> +#define LBUS(obj) OBJECT_CHECK(LBus, (obj), TYPE_LBUS)
>> +#define LBUS_CLASS(klass) \
>> +    OBJECT_CLASS_CHECK(LBusClass, (klass), TYPE_LBUS)
>> +#define LBUS_GET_CLASS(obj) \
>> +    OBJECT_GET_CLASS(LBusClass, (obj), TYPE_LBUS)
> Same here.
Fixed.
>
>> +
>> +typedef struct LBus {
>> +    BusState bus;
>> +
>> +    MemoryRegion mr;
>> +
>> +    QLIST_HEAD(, LBusNode) devices;
>> +} LBus;
>> +
>> +DeviceState *lbus_create_device(LBus *bus, const char *type, uint32_t addr);
>> +int lbus_add_device(LBus *bus, LBusDevice *dev);
>> +#endif /* FSI_LBUS_H */
>> --
>> 2.39.2
>>
Thanks for the review

Ninad