Re: [PATCH 15/16] target/mips/cpu: Do not allow system-mode use without input clock

[Igor Mammedov <imammedo@redhat.com>]

On Mon, 28 Sep 2020 19:15:38 +0200
Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:

> Now than all QOM users provides the input clock, do not allow
> using a CPU core without its input clock connected on system-mode
> emulation. For user-mode, keep providing a fixed 200 MHz clock,
> as it used by the RDHWR instruction (see commit cdfcad788394).
> 
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
> Cc: Igor Mammedov <imammedo@redhat.com>
> 
> We need the qtest check for tests/qtest/machine-none-test.c
> which instanciate a CPU with the none machine. Igor, is it
> better to remove the MIPS targets from the test cpus_map[]?

I don't get idea, could you rephrase/elaborate?

> ---
>  target/mips/cpu.c | 8 ++++++++
>  1 file changed, 8 insertions(+)
> 
> diff --git a/target/mips/cpu.c b/target/mips/cpu.c
> index 2f75216c324..cc4ee75af30 100644
> --- a/target/mips/cpu.c
> +++ b/target/mips/cpu.c
> @@ -25,6 +25,7 @@
>  #include "kvm_mips.h"
>  #include "qemu/module.h"
>  #include "sysemu/kvm.h"
> +#include "sysemu/qtest.h"
>  #include "exec/exec-all.h"
>  #include "hw/qdev-clock.h"
>  #include "hw/qdev-properties.h"
> @@ -159,11 +160,18 @@ static void mips_cpu_realizefn(DeviceState *dev, Error **errp)
>      Error *local_err = NULL;
>  
>      if (!clock_get(cs->clock)) {
> +#ifdef CONFIG_USER_ONLY
>          /*
>           * Initialize the frequency to 200MHz in case
>           * the clock remains unconnected.
>           */
>          clock_set_hz(cs->clock, 200000000);
> +#else
> +        if (!qtest_enabled()) {
> +            error_setg(errp, "CPU clock must be connected to a clock source");
> +            return;
> +        }
> +#endif
>      }
>      mips_cpu_clk_update(cs);
>