Re: [PATCH for-6.2 08/25] hw/arm/mps2.c: Connect up armv7m clocks

[Luc Michel]

On 10:33 Thu 12 Aug     , Peter Maydell wrote:
> Connect up the armv7m clocks on the mps2-an385/386/500/511.
> 
> Connect up the armv7m object's clocks on the MPS boards defined in
> mps2.c.  The documentation for these FPGA images doesn't specify what
> systick reference clock is used (if any), so for the moment we
> provide a 1MHz refclock, which will result in no behavioural change
> from the current hardwired 1MHz clock implemented in
> armv7m_systick.c:systick_scale().
> 
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

Reviewed-by: Luc Michel <luc@lmichel.fr>

> ---
>  hw/arm/mps2.c | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/hw/arm/mps2.c b/hw/arm/mps2.c
> index 81413b7133e..3671f49ad7b 100644
> --- a/hw/arm/mps2.c
> +++ b/hw/arm/mps2.c
> @@ -86,6 +86,7 @@ struct MPS2MachineState {
>      CMSDKAPBWatchdog watchdog;
>      CMSDKAPBTimer timer[2];
>      Clock *sysclk;
> +    Clock *refclk;
>  };
>  
>  #define TYPE_MPS2_MACHINE "mps2"
> @@ -99,6 +100,15 @@ OBJECT_DECLARE_TYPE(MPS2MachineState, MPS2MachineClass, 
> MPS2_MACHINE)
>  /* Main SYSCLK frequency in Hz */
>  #define SYSCLK_FRQ 25000000
>  
> +/*
> + * The Application Notes don't say anything about how the
> + * systick reference clock is configured. (Quite possibly
> + * they don't have one at all.) This 1MHz clock matches the
> + * pre-existing behaviour that used to be hardcoded in the
> + * armv7m_systick implementation.
> + */
> +#define REFCLK_FRQ (1 * 1000 * 1000)
> +
>  /* Initialize the auxiliary RAM region @mr and map it into
>   * the memory map at @base.
>   */
> @@ -146,6 +156,9 @@ static void mps2_common_init(MachineState *machine)
>      mms->sysclk = clock_new(OBJECT(machine), "SYSCLK");
>      clock_set_hz(mms->sysclk, SYSCLK_FRQ);
>  
> +    mms->refclk = clock_new(OBJECT(machine), "REFCLK");
> +    clock_set_hz(mms->refclk, REFCLK_FRQ);
> +
>      /* The FPGA images have an odd combination of different RAMs,
>       * because in hardware they are different implementations and
>       * connected to different buses, giving varying performance/size
> @@ -223,6 +236,8 @@ static void mps2_common_init(MachineState *machine)
>      default:
>          g_assert_not_reached();
>      }
> +    qdev_connect_clock_in(armv7m, "cpuclk", mms->sysclk);
> +    qdev_connect_clock_in(armv7m, "refclk", mms->refclk);
>      qdev_prop_set_string(armv7m, "cpu-type", machine->cpu_type);
>      qdev_prop_set_bit(armv7m, "enable-bitband", true);
>      object_property_set_link(OBJECT(&mms->armv7m), "memory",
> -- 
> 2.20.1
> 

--