Re: [PATCH 13/25] hw/arm/mps2: Create and connect SYSCLK Clock

From: Luc Michel <luc@lmichel.fr>
To: Peter Maydell <peter.maydell@linaro.org>
Cc: "Damien Hedde" <damien.hedde@greensocs.com>,
	qemu-arm@nongnu.org, qemu-devel@nongnu.org,
	"Philippe Mathieu-Daudé" <f4bug@amsat.org>
Subject: Re: [PATCH 13/25] hw/arm/mps2: Create and connect SYSCLK Clock
Date: Fri, 22 Jan 2021 20:52:15 +0100	[thread overview]
Message-ID: <20210122195215.yw7qoldfdyojsaxn@sekoia-pc.home.lmichel.fr> (raw)
In-Reply-To: <20210121190622.22000-14-peter.maydell@linaro.org>

On 19:06 Thu 21 Jan     , Peter Maydell wrote:
> Create a fixed-frequency Clock object to be the SYSCLK, and wire it
> up to the devices that require it.
> 
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

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

> ---
>  hw/arm/mps2.c | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/hw/arm/mps2.c b/hw/arm/mps2.c
> index f762d1b46af..cd1c215f941 100644
> --- a/hw/arm/mps2.c
> +++ b/hw/arm/mps2.c
> @@ -46,6 +46,7 @@
>  #include "hw/net/lan9118.h"
>  #include "net/net.h"
>  #include "hw/watchdog/cmsdk-apb-watchdog.h"
> +#include "hw/qdev-clock.h"
>  #include "qom/object.h"
>  
>  typedef enum MPS2FPGAType {
> @@ -84,6 +85,7 @@ struct MPS2MachineState {
>      CMSDKAPBDualTimer dualtimer;
>      CMSDKAPBWatchdog watchdog;
>      CMSDKAPBTimer timer[2];
> +    Clock *sysclk;
>  };
>  
>  #define TYPE_MPS2_MACHINE "mps2"
> @@ -140,6 +142,10 @@ static void mps2_common_init(MachineState *machine)
>          exit(EXIT_FAILURE);
>      }
>  
> +    /* This clock doesn't need migration because it is fixed-frequency */
> +    mms->sysclk = clock_new(OBJECT(machine), "SYSCLK");
> +    clock_set_hz(mms->sysclk, SYSCLK_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
> @@ -341,6 +347,7 @@ static void mps2_common_init(MachineState *machine)
>                                  TYPE_CMSDK_APB_TIMER);
>          sbd = SYS_BUS_DEVICE(&mms->timer[i]);
>          qdev_prop_set_uint32(DEVICE(&mms->timer[i]), "pclk-frq", SYSCLK_FRQ);
> +        qdev_connect_clock_in(DEVICE(&mms->timer[i]), "pclk", mms->sysclk);
>          sysbus_realize_and_unref(sbd, &error_fatal);
>          sysbus_mmio_map(sbd, 0, base);
>          sysbus_connect_irq(sbd, 0, qdev_get_gpio_in(armv7m, irqno));
> @@ -349,6 +356,7 @@ static void mps2_common_init(MachineState *machine)
>      object_initialize_child(OBJECT(mms), "dualtimer", &mms->dualtimer,
>                              TYPE_CMSDK_APB_DUALTIMER);
>      qdev_prop_set_uint32(DEVICE(&mms->dualtimer), "pclk-frq", SYSCLK_FRQ);
> +    qdev_connect_clock_in(DEVICE(&mms->dualtimer), "TIMCLK", mms->sysclk);
>      sysbus_realize(SYS_BUS_DEVICE(&mms->dualtimer), &error_fatal);
>      sysbus_connect_irq(SYS_BUS_DEVICE(&mms->dualtimer), 0,
>                         qdev_get_gpio_in(armv7m, 10));
> @@ -356,6 +364,7 @@ static void mps2_common_init(MachineState *machine)
>      object_initialize_child(OBJECT(mms), "watchdog", &mms->watchdog,
>                              TYPE_CMSDK_APB_WATCHDOG);
>      qdev_prop_set_uint32(DEVICE(&mms->watchdog), "wdogclk-frq", SYSCLK_FRQ);
> +    qdev_connect_clock_in(DEVICE(&mms->watchdog), "WDOGCLK", mms->sysclk);
>      sysbus_realize(SYS_BUS_DEVICE(&mms->watchdog), &error_fatal);
>      sysbus_connect_irq(SYS_BUS_DEVICE(&mms->watchdog), 0,
>                         qdev_get_gpio_in_named(armv7m, "NMI", 0));
> -- 
> 2.20.1
> 

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