On 2017年08月31日 23:38, Roger Pau Monné wrote:
> On Thu, Aug 31, 2017 at 01:01:47AM -0400, Lan Tianyu wrote:
>> This patch is to change DSDT table for processor object to support >128 vcpus
>> accroding to ACPI spec 8.4 Declaring Processors
>>
>> Signed-off-by: Lan Tianyu <tianyu....@intel.com>
>> ---
>> tools/libacpi/mk_dsdt.c | 18 ++++++++++++------
>> 1 file changed, 12 insertions(+), 6 deletions(-)
>>
>> diff --git a/tools/libacpi/mk_dsdt.c b/tools/libacpi/mk_dsdt.c
>> index 2daf32c..6c4c325 100644
>> --- a/tools/libacpi/mk_dsdt.c
>> +++ b/tools/libacpi/mk_dsdt.c
>> @@ -24,6 +24,8 @@
>> #include <xen/arch-arm.h>
>> #endif
>>
>> +#define CPU_NAME_FMT "P%.03X"
>> +
>> static unsigned int indent_level;
>> static bool debug = false;
>>
>> @@ -196,10 +198,14 @@ int main(int argc, char **argv)
>> /* Define processor objects and control methods. */
>> for ( cpu = 0; cpu < max_cpus; cpu++)
>> {
>> - push_block("Processor", "PR%02X, %d, 0x0000b010, 0x06", cpu, cpu);
>> + unsigned int apic_id = cpu * 2;
>
> This is fragile, ideally there should be a single point where the APIC
> ID is calculated. Although there are already two places where the APIC
> ID is calculated, in hvmloader and libxl.
>
> And I'm not sure how to use any of those here in order to avoid
> introducing a third one.
The mk_dsdt is independent tool to build dsdt table. It wasn't linked
with libxl and hvmloader. We can't reuse old function to do that.
But I think we may introduce a new LAPIC_ID(vcpu) in the arch head
file(i.e, #include <xen/arch-x86/xen.h>) and replace old ones.
>
>>
>> - stmt("Name", "_HID, \"ACPI0007\"");
>> + if ( apic_id > 255 )
>
> We need to be careful with this. This is not a problem ATM because the
> ACPI ID is the CPU ID, but care should be taken to not create a
> Processor object with ACPI ID 255, because that's the broadcast ACPI
> ID...
Yes.
>
>> + push_block("Device", CPU_NAME_FMT, cpu);
>> + else
>
> ... IMHO an assert(cpu < 255); should be added here.
OK.
>
>> + push_block("Processor", CPU_NAME_FMT", %d, 0x0000b010, 0x06",
>> cpu, cpu);
> ^ space (here and below)
>
> Please leave a space between the string literals and the defines, it
> makes it easier to read. And this line needs to be split.
>
OK. Will update.
--
Best regards
Tianyu Lan
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