Re: [PATCH 3/9] intc/grlib_irqmp: implements the multiprocessor status register

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

Hi Clément,

On 5/1/24 11:24, Clément Chigot wrote:
> This implements the multiprocessor status register in grlib-irqmp and bind
> it to a start signal, which will be later wired in leon3-generic to
> start a cpu.
> 
> Co-developed-by: Frederic Konrad <konrad.frederic@yahoo.fr>
> Signed-off-by: Clément Chigot <chigot@adacore.com>
> ---
>   hw/intc/grlib_irqmp.c | 22 +++++++++++++++++++---
>   1 file changed, 19 insertions(+), 3 deletions(-)


> @@ -323,6 +334,8 @@ static void grlib_irqmp_reset(DeviceState *d)
>   
>       memset(irqmp->state, 0, sizeof *irqmp->state);
>       irqmp->state->parent = irqmp;
> +    irqmp->state->mpstatus = ((irqmp->ncpus - 1) << 28)

Can you #define this magic '28' number?

> +        | ((1 << irqmp->ncpus) - 2);
>   }
>   
>   static void grlib_irqmp_realize(DeviceState *dev, Error **errp)
> @@ -336,6 +349,9 @@ static void grlib_irqmp_realize(DeviceState *dev, Error **errp)
>       }
>   
>       qdev_init_gpio_in(dev, grlib_irqmp_set_irq, MAX_PILS);
> +    /* Transitionning from 0 to 1 starts the CPUs.  */

What about 1 -> 0?

> +    qdev_init_gpio_out_named(dev, irqmp->start_signal, "grlib-start-cpu",
> +                             IRQMP_MAX_CPU);
>       qdev_init_gpio_out_named(dev, &irqmp->irq, "grlib-irq", 1);
>       memory_region_init_io(&irqmp->iomem, OBJECT(dev), &grlib_irqmp_ops, irqmp,
>                             "irqmp", IRQMP_REG_SIZE);