Re: [Qemu-devel] [RFC PATCH 03/11] qemu-clk: allow to bound two clocks together

[Peter Maydell <peter.maydell@linaro.org>]

On 13 June 2016 at 17:27,  <fred.konrad@greensocs.com> wrote:
> From: KONRAD Frederic <fred.konrad@greensocs.com>
>
> This introduces the clock binding and the update part.
> When the qemu_clk_rate_update(qemu_clk, int) function is called:
>   * The clock callback is called on the qemu_clk so it can change the rate.
>   * The qemu_clk_rate_update function is called on all the driven clock.
>
> Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
> ---
>  include/qemu/qemu-clock.h | 65 +++++++++++++++++++++++++++++++++++++++++++++++
>  qemu-clock.c              | 56 ++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 121 insertions(+)
>
> diff --git a/include/qemu/qemu-clock.h b/include/qemu/qemu-clock.h
> index a2ba105..677de9a 100644
> --- a/include/qemu/qemu-clock.h
> +++ b/include/qemu/qemu-clock.h
> @@ -27,15 +27,29 @@
>  #include "qemu/osdep.h"
>  #include "qom/object.h"
>
> +typedef float (*qemu_clk_on_rate_update_cb)(void *opaque, float rate);
> +
>  #define TYPE_CLOCK "qemu-clk"
>  #define QEMU_CLOCK(obj) OBJECT_CHECK(struct qemu_clk, (obj), TYPE_CLOCK)
>
> +typedef struct ClkList ClkList;
> +
>  typedef struct qemu_clk {
>      /*< private >*/
>      Object parent_obj;
>      char *name;            /* name of this clock in the device. */
> +    float in_rate;         /* rate of the clock which drive this pin. */
> +    float out_rate;        /* rate of this clock pin. */

I'm rather dubious that we should be using floats here.
Almost nothing in our hardware emulation uses float or double.

> +    void *opaque;
> +    qemu_clk_on_rate_update_cb cb;
> +    QLIST_HEAD(, ClkList) bound;
>  } *qemu_clk;

thanks
-- PMM