Re: [Qemu-devel] [PATCH v2 1/4] acpi: Add ACPI_CPU_HOTPLUG_ID_LIMIT macro

[Eduardo Habkost]

On Wed, Mar 12, 2014 at 10:18:56PM +0100, Laszlo Ersek wrote:
> On 03/12/14 22:17, Laszlo Ersek wrote:
> > On 03/12/14 19:28, Eduardo Habkost wrote:
> >> The new macro will be helpful to allow us to detect too large SMP limits
> >> before it is too late.
> >>
> >> Signed-off-by: Eduardo Habkost <address@hidden>
> >> ---
> >>  include/hw/acpi/cpu_hotplug_defs.h | 8 ++++++++
> >>  1 file changed, 8 insertions(+)
> >>
> >> diff --git a/include/hw/acpi/cpu_hotplug_defs.h 
> >> b/include/hw/acpi/cpu_hotplug_defs.h
> >> index 2725b50..9f33663 100644
> >> --- a/include/hw/acpi/cpu_hotplug_defs.h
> >> +++ b/include/hw/acpi/cpu_hotplug_defs.h
> >> @@ -17,7 +17,15 @@
> >>   * between C and ASL code.
> >>   */
> >>  #define ACPI_CPU_HOTPLUG_STATUS 4
> >> +
> >> +/* Limit for CPU arch IDs for CPU hotplug. All hotpluggable CPUs should
> >> + * have CPUClass.get_arch_id() < ACPI_CPU_HOTPLUG_ID_LIMIT.
> >> + */
> >> +#define ACPI_CPU_HOTPLUG_ID_LIMIT 256
> >> +
> >> +/* 256 CPU IDs, 8 bits per entry: */
> >>  #define ACPI_GPE_PROC_LEN 32
> >> +
> >>  #define ICH9_CPU_HOTPLUG_IO_BASE 0x0CD8
> >>  #define PIIX4_CPU_HOTPLUG_IO_BASE 0xaf00
> >>  
> >>
> > 
> > You could actually derive ACPI_GPE_PROC_LEN from
> > ACPI_CPU_HOTPLUG_ID_LIMIT, by dividing with CHAR_BIT.
> 
> 
> (Or vice versa -- get the limit from PROC_LEN by multiplication.)

I tried it, but the ASL compiler doesn't seem to be able to evaluate the
expression.

-- 
Eduardo