Re: [Qemu-devel] [PATCH v7 04/13] qdev: allow multiple qdev_init_gpio_in() calls

[Peter Maydell]

On 24 September 2012 10:18, Peter A. G. Crosthwaite
<address@hidden> wrote:
> Allow multiple qdev_init_gpio_in() calls for the one device. The first call 
> will
> define GPIOs 0-N-1, the next GPIOs N- ... . Allows different GPIOs to be 
> handled
> with different handlers. Needed when two levels of the QOM class heirachy both
> define GPIO functionality, as a single GPIO handler with an index selecter is
> not possible.
>
> Signed-off-by: Peter A. G. Crosthwaite <address@hidden>
> ---
> changed since v5:
> moved implementation to irq.c as per PMM review

Thanks for this change -- I think it looks much cleaner this way.

>  hw/irq.c  |   17 ++++++++++++++---
>  hw/irq.h  |   11 ++++++++++-
>  hw/qdev.c |    6 +++---
>  3 files changed, 27 insertions(+), 7 deletions(-)
>
> diff --git a/hw/irq.c b/hw/irq.c
> index d413a0b..cd17551 100644
> --- a/hw/irq.c
> +++ b/hw/irq.c
> @@ -38,15 +38,20 @@ void qemu_set_irq(qemu_irq irq, int level)
>      irq->handler(irq->opaque, irq->n, level);
>  }
>
> -qemu_irq *qemu_allocate_irqs(qemu_irq_handler handler, void *opaque, int n)
> +qemu_irq *qemu_extend_irqs(qemu_irq *old, int n_old, qemu_irq_handler 
> handler,
> +                                void *opaque, int n)

Your indent is a little odd here (and below) -- usually the parameters
in the second line are aligned with the first (so the 'v' is in the
same column as the 'q').

>  {
>      qemu_irq *s;
>      struct IRQState *p;
>      int i;
>
> -    s = (qemu_irq *)g_malloc0(sizeof(qemu_irq) * n);
> +    if (!old) {
> +        n_old = 0;
> +    }
> +    s = old ? g_renew(qemu_irq, old, n + n_old) :
> +                    (qemu_irq *)g_new0(qemu_irq, n);

You don't need to cast the return value from g_new0().
Also, this isn't consistent -- either we don't need the
memory zeroed (in which case use g_new rather than g_new0)
or we do (in which case we need to do something about
the new memory g_renew() returns).

>      p = (struct IRQState *)g_malloc0(sizeof(struct IRQState) * n);

qemu_free_irqs() relies on all the struct IRQState *s being
freeable with a single g_free(), so you need to g_renew the
existing array here.

> -    for (i = 0; i < n; i++) {
> +    for (i = n_old; i < n + n_old; i++) {
>          p->handler = handler;
>          p->opaque = opaque;
>          p->n = i;
> @@ -56,6 +61,12 @@ qemu_irq *qemu_allocate_irqs(qemu_irq_handler handler, 
> void *opaque, int n)
>      return s;
>  }
>
> +qemu_irq *qemu_allocate_irqs(qemu_irq_handler handler, void *opaque, int n)
> +{
> +    return qemu_extend_irqs(NULL, 0, handler, opaque, n);
> +}
> +
> +
>  void qemu_free_irqs(qemu_irq *s)
>  {
>      g_free(s[0]);
> diff --git a/hw/irq.h b/hw/irq.h
> index 56c55f0..e640c10 100644
> --- a/hw/irq.h
> +++ b/hw/irq.h
> @@ -23,8 +23,17 @@ static inline void qemu_irq_pulse(qemu_irq irq)
>      qemu_set_irq(irq, 0);
>  }
>
> -/* Returns an array of N IRQs.  */
> +/* Returns an array of N IRQs. Each IRQ is assigned the argument handler and
> + * opaque data.
> + */
>  qemu_irq *qemu_allocate_irqs(qemu_irq_handler handler, void *opaque, int n);
> +
> +/* Extends an Array of IRQs. Old IRQs have their handlers and opaque data
> + * preserved. New IRQs are assigned the argument handler and opaque data.
> + */
> +qemu_irq *qemu_extend_irqs(qemu_irq *old, int n_old, qemu_irq_handler 
> handler,
> +                                void *opaque, int n);
> +
>  void qemu_free_irqs(qemu_irq *s);
>
>  /* Returns a new IRQ with opposite polarity.  */
> diff --git a/hw/qdev.c b/hw/qdev.c
> index b5a52ac..eea9eae 100644
> --- a/hw/qdev.c
> +++ b/hw/qdev.c
> @@ -291,9 +291,9 @@ BusState *qdev_get_parent_bus(DeviceState *dev)
>
>  void qdev_init_gpio_in(DeviceState *dev, qemu_irq_handler handler, int n)
>  {
> -    assert(dev->num_gpio_in == 0);
> -    dev->num_gpio_in = n;
> -    dev->gpio_in = qemu_allocate_irqs(handler, dev, n);
> +    dev->gpio_in = qemu_extend_irqs(dev->gpio_in, dev->num_gpio_in, handler,
> +                                        dev, n);
> +    dev->num_gpio_in += n;
>  }
>
>  void qdev_init_gpio_out(DeviceState *dev, qemu_irq *pins, int n)
> --
> 1.7.0.4
>



-- PMM