Re: [PATCH v7 01/10] hw/fsi: Introduce IBM's Local bus

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

Hello Cedric,

On 11/27/23 10:04, Cédric Le Goater wrote:
> On 10/26/23 18:47, Ninad Palsule 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: Ninad Palsule <ninad@linux.ibm.com>
>> ---
>> v2:
>> - Incorporated Joel's review comments.
>> v5:
>> - Incorporated review comments by Cedric.
>> v6:
>> - Incorporated review comments by Cedric & Daniel.
>> v7:
>> - Incorporated review comments by Philippe.
>> ---
>>   include/hw/fsi/lbus.h | 43 +++++++++++++++++++++++++
>>   hw/fsi/lbus.c         | 74 +++++++++++++++++++++++++++++++++++++++++++
>>   hw/Kconfig            |  1 +
>>   hw/fsi/Kconfig        |  2 ++
>>   hw/fsi/meson.build    |  1 +
>>   hw/meson.build        |  1 +
>>   6 files changed, 122 insertions(+)
>>   create mode 100644 include/hw/fsi/lbus.h
>>   create mode 100644 hw/fsi/lbus.c
>>   create mode 100644 hw/fsi/Kconfig
>>   create mode 100644 hw/fsi/meson.build
>>
>> diff --git a/include/hw/fsi/lbus.h b/include/hw/fsi/lbus.h
>> new file mode 100644
>> index 0000000000..4fa696bbdb
>> --- /dev/null
>> +++ b/include/hw/fsi/lbus.h
>> @@ -0,0 +1,43 @@
>> +/*
>> + * 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_FSI_LBUS_DEVICE "fsi.lbus.device"
>> +OBJECT_DECLARE_TYPE(FSILBusDevice, FSILBusDeviceClass, FSI_LBUS_DEVICE)
>> +
>> +#define FSI_LBUS_MEM_REGION_SIZE  (2 * 1024 * 1024)
>> +#define FSI_LBUSDEV_IOMEM_SIZE    0x400
>> +
>> +typedef struct FSILBusDevice {
>> +    DeviceState parent;
>> +
>> +    MemoryRegion iomem;
>> +    uint32_t address;
>
> This is address attribute is not useful. Models/HW unit generally do not
> know where their MMIO regions are mmapped in the address space.
OK, I checked your changes and looks good.
>
>> +} FSILBusDevice;
>> +
>> +typedef struct FSILBusDeviceClass {
>> +    DeviceClass parent;
>> +
>> +    uint32_t config;
>> +} FSILBusDeviceClass;
>> +
>> +#define TYPE_FSI_LBUS "fsi.lbus"
>> +OBJECT_DECLARE_SIMPLE_TYPE(FSILBus, FSI_LBUS)
>> +
>> +typedef struct FSILBus {
>> +    BusState bus;
>> +
>> +    MemoryRegion mr;
>> +} FSILBus;
>> +
>> +DeviceState *lbus_create_device(FSILBus *bus, const char *type, 
>> uint32_t addr);
>> +int lbus_add_device(FSILBus *bus, FSILBusDevice *dev);
>> +#endif /* FSI_LBUS_H */
>> diff --git a/hw/fsi/lbus.c b/hw/fsi/lbus.c
>> new file mode 100644
>> index 0000000000..3a7335dde5
>> --- /dev/null
>> +++ b/hw/fsi/lbus.c
>> @@ -0,0 +1,74 @@
>> +/*
>> + * 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 "hw/fsi/lbus.h"
>> +
>> +#include "hw/qdev-properties.h"
>> +
>> +static void lbus_init(Object *o)
>> +{
>> +    FSILBus *lbus = FSI_LBUS(o);
>> +
>> +    memory_region_init(&lbus->mr, OBJECT(lbus), TYPE_FSI_LBUS,
>> +                       FSI_LBUS_MEM_REGION_SIZE - 
>> FSI_LBUSDEV_IOMEM_SIZE);
>> +}
>> +
>> +static const TypeInfo lbus_info = {
>> +    .name = TYPE_FSI_LBUS,
>> +    .parent = TYPE_BUS,
>> +    .instance_init = lbus_init,
>> +    .instance_size = sizeof(FSILBus),
>> +};
>> +
>> +static Property lbus_device_props[] = {
>> +    DEFINE_PROP_UINT32("address", FSILBusDevice, address, 0),
>> +    DEFINE_PROP_END_OF_LIST(),
>> +};
>
> Please remove lbus_device_props
ok, I checked your changes and look good.
>
>> +DeviceState *lbus_create_device(FSILBus *bus, const char *type, 
>> uint32_t addr)
>
> This routine is only used once in a realize handler which could propagate
> a possible error. Please remove.
ok, I checked your changes and look good.
>
>> +{
>> +    DeviceState *ds;
>> +    BusState *state = BUS(bus);
>> +    FSILBusDevice *dev;
>> +
>> +    ds = qdev_new(type);
>> +    qdev_prop_set_uint32(ds, "address", addr);
>> +    qdev_realize_and_unref(ds, state, &error_fatal);
>> +
>> +    dev = FSI_LBUS_DEVICE(ds);
>> +    memory_region_add_subregion(&bus->mr, dev->address,
>> +                                &dev->iomem);
>> +
>> +    return ds;
>> +}
>> +
>> +static void lbus_device_class_init(ObjectClass *klass, void *data)
>> +{
>> +    DeviceClass *dc = DEVICE_CLASS(klass);
>> +
>> +    dc->bus_type = TYPE_FSI_LBUS;
>> +    device_class_set_props(dc, lbus_device_props);
>> +}
>> +
>> +static const TypeInfo lbus_device_type_info = {
>> +    .name = TYPE_FSI_LBUS_DEVICE,
>> +    .parent = TYPE_DEVICE,
>> +    .instance_size = sizeof(FSILBusDevice),
>> +    .abstract = true,
>> +    .class_init = lbus_device_class_init,
>> +    .class_size = sizeof(FSILBusDeviceClass),
>> +};
>> +
>> +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/Kconfig b/hw/Kconfig
>> index 9ca7b38c31..2c00936c28 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..e650c660f0
>> --- /dev/null
>> +++ b/hw/fsi/Kconfig
>> @@ -0,0 +1,2 @@
>> +config FSI_LBUS
>> +    bool
>> diff --git a/hw/fsi/meson.build b/hw/fsi/meson.build
>> new file mode 100644
>> index 0000000000..4074d3a7d2
>> --- /dev/null
>> +++ b/hw/fsi/meson.build
>> @@ -0,0 +1 @@
>> +system_ss.add(when: 'CONFIG_FSI_LBUS', if_true: files('lbus.c'))
>> diff --git a/hw/meson.build b/hw/meson.build
>> index f01fac4617..463d702683 100644
>> --- a/hw/meson.build
>> +++ b/hw/meson.build
>> @@ -44,6 +44,7 @@ subdir('virtio')
>>   subdir('watchdog')
>>   subdir('xen')
>>   subdir('xenpv')
>> +subdir('fsi')
>>     subdir('alpha')
>>   subdir('arm')
>
> The meson.build file is not modified which means the new files are 
> compiled.

Sorry, I missed it.

Thanks for the review and changes.

Regards,

Ninad


>
>
> Thanks,
>
> C.
>