Re: [Qemu-devel] [PATCH v10 02/21] i.MX: Move serial initialization to init/realize of DeviceClass.

[Peter Crosthwaite <peter.crosthwaite@xilinx.com>]

On Mon, Jul 6, 2015 at 1:01 AM,  <jcd@tribudubois.net> wrote:
>
>
> ----- Le 6 Juil 15, à 8:40, Peter Crosthwaite <peter.crosthwaite@xilinx.com>
> a écrit :
>
> On Sun, Jul 5, 2015 at 5:04 PM, Jean-Christophe Dubois
> <jcd@tribudubois.net> wrote:
>> Move constructor to DeviceClass methods
>>  * imx_serial_init
>>  * imx_serial_realize
>>
>> imx32_serial_properties is renamed to imx_serial_properties.
>>
>> The Qdev construction helper is moved to an include file as an
>> inline function. This function is going to be removed soon.
>>
>> Signed-off-by: Jean-Christophe Dubois <jcd@tribudubois.net>
>> ---
>>
>> Changes since v1:
>>     * not present on v1
>>
>> Changes since v2:
>>     * not present on v2
>>
>> Changes since v3:
>>     * not present on v3
>>
>> Changes since v4:
>>     * not present on v4
>>
>> Changes since v5:
>>     * not present on v5
>>
>> Changes since v6:
>>     * not present on v6
>>
>> Changes since v7:
>>     * not present on v7
>>
>> Changes since v8:
>>     * Remove Qdev construction helper
>>
>> Changes since v9:
>>     * Qdev construction helper is reintegrated and moved to a header file
>>       as an inline function.
>>
>>  hw/char/imx_serial.c | 70
>> +++++++++++++++-------------------------------------
>>  include/hw/arm/imx.h | 30 +++++++++++++++++++++-
>>  2 files changed, 49 insertions(+), 51 deletions(-)
>>
>> diff --git a/hw/char/imx_serial.c b/hw/char/imx_serial.c
>> index 1dcb325..ef5af05 100644
>> --- a/hw/char/imx_serial.c
>> +++ b/hw/char/imx_serial.c
>> @@ -21,7 +21,6 @@
>>  #include "hw/char/imx_serial.h"
>>  #include "sysemu/sysemu.h"
>>  #include "sysemu/char.h"
>> -#include "hw/arm/imx.h"
>>
>>  //#define DEBUG_SERIAL 1
>>  #ifdef DEBUG_SERIAL
>> @@ -38,13 +37,13 @@ do { printf("imx_serial: " fmt , ##args); } while (0)
>>  //#define DEBUG_IMPLEMENTATION 1
>>  #ifdef DEBUG_IMPLEMENTATION
>>  #  define IPRINTF(fmt, args...) \
>> -    do  { fprintf(stderr, "imx_serial: " fmt, ##args); } while (0)
>> +    do  { fprintf(stderr, "%s: " fmt, TYPE_IMX_SERIAL, ##args); } while
>> (0)
>>  #else
>>  #  define IPRINTF(fmt, args...) do {} while (0)
>>  #endif
>>
>>  static const VMStateDescription vmstate_imx_serial = {
>> -    .name = "imx-serial",
>> +    .name = TYPE_IMX_SERIAL,
>>      .version_id = 1,
>>      .minimum_version_id = 1,
>>      .fields = (VMStateField[]) {
>> @@ -299,22 +298,18 @@ static void imx_event(void *opaque, int event)
>>      }
>>  }
>>
>> -
>>  static const struct MemoryRegionOps imx_serial_ops = {
>>      .read = imx_serial_read,
>>      .write = imx_serial_write,
>>      .endianness = DEVICE_NATIVE_ENDIAN,
>>  };
>>
>> -static int imx_serial_init(SysBusDevice *dev)
>> +static void imx_serial_realize(DeviceState *dev, Error **errp)
>>  {
>>      IMXSerialState *s = IMX_SERIAL(dev);
>>
>> -
>> -    memory_region_init_io(&s->iomem, OBJECT(s), &imx_serial_ops, s,
>> -                          "imx-serial", 0x1000);
>> -    sysbus_init_mmio(dev, &s->iomem);
>> -    sysbus_init_irq(dev, &s->irq);
>> +    /* FIXME use a qdev chardev prop instead of
>> qemu_char_get_next_serial() */
>> +    s->chr = qemu_char_get_next_serial();
>>
>>      if (s->chr) {
>>          qemu_chr_add_handlers(s->chr, imx_can_receive, imx_receive,
>> @@ -323,45 +318,20 @@ static int imx_serial_init(SysBusDevice *dev)
>>          DPRINTF("No char dev for uart at 0x%lx\n",
>>                  (unsigned long)s->iomem.ram_addr);
>>      }
>> -
>> -    return 0;
>>  }
>>
>> -void imx_serial_create(int uart, const hwaddr addr, qemu_irq irq)
>> +static void imx_serial_init(Object *obj)
>>  {
>> -    DeviceState *dev;
>> -    SysBusDevice *bus;
>> -    CharDriverState *chr;
>> -    const char chr_name[] = "serial";
>> -    char label[ARRAY_SIZE(chr_name) + 1];
>> -
>> -    dev = qdev_create(NULL, TYPE_IMX_SERIAL);
>> -
>> -    if (uart >= MAX_SERIAL_PORTS) {
>> -        hw_error("Cannot assign uart %d: QEMU supports only %d ports\n",
>> -                 uart, MAX_SERIAL_PORTS);
>> -    }
>> -    chr = serial_hds[uart];
>> -    if (!chr) {
>> -        snprintf(label, ARRAY_SIZE(label), "%s%d", chr_name, uart);
>> -        chr = qemu_chr_new(label, "null", NULL);
>> -        if (!(chr)) {
>> -            hw_error("Can't assign serial port to imx-uart%d.\n", uart);
>> -        }
>> -    }
>> -
>> -    qdev_prop_set_chr(dev, "chardev", chr);
>
> I'm confused as to why you needed to replace the qdev_prop_set_chr
> logic with qemu_get_char_get_next_serial(). Can you give some details
> on why we want to do this?
>
>
> I am just following the general ARM template of other serial drivers. I am
> not proficient enough in Qemu wizardry to proprose my own thing in this
> regard.
> So far no other ARM plateform (except strongarm?) seems to be using
> "chardev" and all seems to be using qemu_get_char_get_next_serial() even if
> it is supposed to be deprecated some day (even the cadence serial driver).
>

I wonder if this one is right, and everyone else is wrong.
Propertyified chr is better than the devs using
qemu_chr_get_next_serial.

>
>> -    bus = SYS_BUS_DEVICE(dev);
>> -    qdev_init_nofail(dev);
>> -    if (addr != (hwaddr)-1) {
>> -        sysbus_mmio_map(bus, 0, addr);
>> -    }
>> -    sysbus_connect_irq(bus, 0, irq);
>> +    SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
>> +    IMXSerialState *s = IMX_SERIAL(obj);
>>
>> +    memory_region_init_io(&s->iomem, obj, &imx_serial_ops, s,
>> +                          TYPE_IMX_SERIAL, 0x1000);
>> +    sysbus_init_mmio(sbd, &s->iomem);
>> +    sysbus_init_irq(sbd, &s->irq);
>>  }
>>
>> -
>> -static Property imx32_serial_properties[] = {
>> +static Property imx_serial_properties[] = {
>>      DEFINE_PROP_CHR("chardev", IMXSerialState, chr),
>>      DEFINE_PROP_END_OF_LIST(),
>>  };
>> @@ -369,21 +339,21 @@ static Property imx32_serial_properties[] = {
>>  static void imx_serial_class_init(ObjectClass *klass, void *data)
>>  {
>>      DeviceClass *dc = DEVICE_CLASS(klass);
>> -    SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
>>
>> -    k->init = imx_serial_init;
>> +    dc->realize = imx_serial_realize;
>>      dc->vmsd = &vmstate_imx_serial;
>>      dc->reset = imx_serial_reset_at_boot;
>>      set_bit(DEVICE_CATEGORY_INPUT, dc->categories);
>>      dc->desc = "i.MX series UART";
>> -    dc->props = imx32_serial_properties;
>> +    dc->props = imx_serial_properties;
>>  }
>>
>>  static const TypeInfo imx_serial_info = {
>> -    .name = TYPE_IMX_SERIAL,
>> -    .parent = TYPE_SYS_BUS_DEVICE,
>> -    .instance_size = sizeof(IMXSerialState),
>> -    .class_init = imx_serial_class_init,
>> +    .name           = TYPE_IMX_SERIAL,
>> +    .parent         = TYPE_SYS_BUS_DEVICE,
>> +    .instance_size  = sizeof(IMXSerialState),
>> +    .instance_init  = imx_serial_init,
>> +    .class_init     = imx_serial_class_init,
>>  };
>>
>>  static void imx_serial_register_types(void)
>> diff --git a/include/hw/arm/imx.h b/include/hw/arm/imx.h
>> index ea9e093..b861e80 100644
>> --- a/include/hw/arm/imx.h
>> +++ b/include/hw/arm/imx.h
>> @@ -11,7 +11,34 @@
>>  #ifndef IMX_H
>>  #define IMX_H
>>
>> -void imx_serial_create(int uart, const hwaddr addr, qemu_irq irq);
>> +#include "hw/qdev-core.h"
>> +#include "hw/sysbus.h"
>> +#include "hw/char/imx_serial.h"
>> +
>> +/***
>> + * This Qdev construction helper is going to be removed soon
>> + */
>> +static inline void imx_serial_create(int uart, const hwaddr addr,
>> qemu_irq irq)
>> +{
>> +   /* uart parameter is not used anymore */
>> +   DeviceState *dev;
>> +
>> +   dev = qdev_create(NULL, TYPE_IMX_SERIAL);
>> +
>> +   if (dev) {
>> +       SysBusDevice *bus;
>> +
>> +       bus = SYS_BUS_DEVICE(dev);
>> +
>> +       qdev_init_nofail(dev);
>> +
>> +       if (addr != (hwaddr)-1) {
>> +           sysbus_mmio_map(bus, 0, addr);
>> +       }
>> +
>> +       sysbus_connect_irq(bus, 0, irq);
>> +   }
>> +}
>
> Can you leave the implementation in imx_serial.c? I don't see the need
> for moving it out. There is no reason the c file cannot have all of
> _init _realize and _create.
>
>
> I sure could, but I wanted to move these Qdev functions to a single place
> where I could nuke them together (removing a single file) when I don't need
> them anymore (when porting KZM to SOC logic).
>

Yes. I made a comment on the KZM patch when I figured it all out.

Regards,
Peter

>
> Regards,
> Peter
>
>>
>>  typedef enum  {
>>      NOCLK,
>> @@ -31,4 +58,5 @@ void imx_timerg_create(const hwaddr addr,
>>                        DeviceState *ccm);
>>
>>
>> +
>>  #endif /* IMX_H */
>> --
>> 2.1.4
>>
>>