Re: [Qemu-devel] [PATCH 2/6] hw/sd/milkymist-memcard: split realize() out of SysBusDevice init()

[Michael Walle <michael@walle.cc>]

Hey Philippe,

Am 2018-01-03 17:23, schrieb Philippe Mathieu-Daudé:
> Create the SDCard in the realize() function.
> 
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
>  hw/sd/milkymist-memcard.c | 24 +++++++++++++++---------
>  1 file changed, 15 insertions(+), 9 deletions(-)
> 
> diff --git a/hw/sd/milkymist-memcard.c b/hw/sd/milkymist-memcard.c
> index 5de3e00e2f..5df3a0f815 100644
> --- a/hw/sd/milkymist-memcard.c
> +++ b/hw/sd/milkymist-memcard.c
> @@ -255,24 +255,29 @@ static void milkymist_memcard_reset(DeviceState 
> *d)
>  static int milkymist_memcard_init(SysBusDevice *dev)
>  {
>      MilkymistMemcardState *s = MILKYMIST_MEMCARD(dev);
> -    DriveInfo *dinfo;
> +
> +    memory_region_init_io(&s->regs_region, OBJECT(s), 
> &memcard_mmio_ops, s,
> +            "milkymist-memcard", R_MAX * 4);
> +    sysbus_init_mmio(dev, &s->regs_region);
> +
> +    return 0;
> +}

Creating the device (milkymist_memcard_create()) fails with an 
assertion:
   sysbus_mmio_map_common: Assertion `n >= 0 && n < dev->num_mmio' 
failed.

because dev->num_mmio is still 0. Seems that sysbus_init_mmio() hasn't 
been called yet. Do we have to move the milkymist_memcard_init() to 
.instance_init?

Eg.

diff --git a/hw/sd/milkymist-memcard.c b/hw/sd/milkymist-memcard.c
index 5df3a0f815..21c0e91926 100644
--- a/hw/sd/milkymist-memcard.c
+++ b/hw/sd/milkymist-memcard.c
@@ -252,15 +252,14 @@ static void milkymist_memcard_reset(DeviceState 
*d)
      }
  }

-static int milkymist_memcard_init(SysBusDevice *dev)
+static void milkymist_memcard_init(Object *obj)
  {
-    MilkymistMemcardState *s = MILKYMIST_MEMCARD(dev);
+    MilkymistMemcardState *s = MILKYMIST_MEMCARD(obj);
+    SysBusDevice *dev = SYS_BUS_DEVICE(obj);

      memory_region_init_io(&s->regs_region, OBJECT(s), 
&memcard_mmio_ops, s,
              "milkymist-memcard", R_MAX * 4);
      sysbus_init_mmio(dev, &s->regs_region);
-
-    return 0;
  }

  static void milkymist_memcard_realize(DeviceState *dev, Error **errp)
@@ -300,9 +299,7 @@ static const VMStateDescription 
vmstate_milkymist_memcard = {
  static void milkymist_memcard_class_init(ObjectClass *klass, void 
*data)
  {
      DeviceClass *dc = DEVICE_CLASS(klass);
-    SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);

-    k->init = milkymist_memcard_init;
      dc->realize = milkymist_memcard_realize;
      dc->reset = milkymist_memcard_reset;
      dc->vmsd = &vmstate_milkymist_memcard;
@@ -314,6 +311,7 @@ static const TypeInfo milkymist_memcard_info = {
      .name          = TYPE_MILKYMIST_MEMCARD,
      .parent        = TYPE_SYS_BUS_DEVICE,
      .instance_size = sizeof(MilkymistMemcardState),
+    .instance_init = milkymist_memcard_init,
      .class_init    = milkymist_memcard_class_init,
  };

-michael

> +
> +static void milkymist_memcard_realize(DeviceState *dev, Error **errp)
> +{
> +    MilkymistMemcardState *s = MILKYMIST_MEMCARD(dev);
>      BlockBackend *blk;
> +    DriveInfo *dinfo;
> 
>      /* FIXME use a qdev drive property instead of drive_get_next() */
>      dinfo = drive_get_next(IF_SD);
>      blk = dinfo ? blk_by_legacy_dinfo(dinfo) : NULL;
>      s->card = sd_init(blk, false);
>      if (s->card == NULL) {
> -        return -1;
> +        error_setg(errp, "failed to init SD card");
> +        return;
>      }
> -
>      s->enabled = blk && blk_is_inserted(blk);
> -
> -    memory_region_init_io(&s->regs_region, OBJECT(s), 
> &memcard_mmio_ops, s,
> -            "milkymist-memcard", R_MAX * 4);
> -    sysbus_init_mmio(dev, &s->regs_region);
> -
> -    return 0;
>  }
> 
>  static const VMStateDescription vmstate_milkymist_memcard = {
> @@ -298,6 +303,7 @@ static void
> milkymist_memcard_class_init(ObjectClass *klass, void *data)
>      SysBusDeviceClass *k = SYS_BUS_DEVICE_CLASS(klass);
> 
>      k->init = milkymist_memcard_init;
> +    dc->realize = milkymist_memcard_realize;
>      dc->reset = milkymist_memcard_reset;
>      dc->vmsd = &vmstate_milkymist_memcard;
>      /* Reason: init() method uses drive_get_next() */