Re: [RFC PATCH 12/12] virt/acpi: add SDEI table if SDEI is enabled

[Guoheyi <guoheyi@huawei.com>]

Thanks for your comments.

On 2019/10/10 17:15, Igor Mammedov wrote:
> On Tue, 24 Sep 2019 23:21:51 +0800
> Heyi Guo <guoheyi@huawei.com> wrote:
>
>> Add SDEI table if SDEI is enabled, so that guest OS can get aware and
>> utilize the interfaces.
>>
>> Signed-off-by: Heyi Guo <guoheyi@huawei.com>
>> Cc: Peter Maydell <peter.maydell@linaro.org>
>> Cc: Dave Martin <Dave.Martin@arm.com>
>> Cc: Marc Zyngier <marc.zyngier@arm.com>
>> Cc: Mark Rutland <mark.rutland@arm.com>
>> Cc: James Morse <james.morse@arm.com>
>> Cc: Shannon Zhao <shannon.zhaosl@gmail.com>
>> Cc: "Michael S. Tsirkin" <mst@redhat.com>
>> Cc: Igor Mammedov <imammedo@redhat.com>
>> ---
>>   hw/arm/virt-acpi-build.c    | 16 ++++++++++++++++
>>   include/hw/acpi/acpi-defs.h |  5 +++++
>>   2 files changed, 21 insertions(+)
>>
>> diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
>> index 6cdf156..1088214 100644
>> --- a/hw/arm/virt-acpi-build.c
>> +++ b/hw/arm/virt-acpi-build.c
>> @@ -32,6 +32,7 @@
>>   #include "trace.h"
>>   #include "hw/core/cpu.h"
>>   #include "target/arm/cpu.h"
>> +#include "target/arm/sdei.h"
>>   #include "hw/acpi/acpi-defs.h"
>>   #include "hw/acpi/acpi.h"
>>   #include "hw/nvram/fw_cfg.h"
>> @@ -475,6 +476,16 @@ build_iort(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
>>   }
>>   
> here should be a comment describing purpose with a reference to spec
OK.

>
>>   static void
>> +build_sdei(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
>> +{
>> +    int sdei_start = table_data->len;
>> +
>> +    (void)acpi_data_push(table_data, sizeof(AcpiSdei));
>> +    build_header(linker, table_data, (void *)(table_data->data + sdei_start),
>> +                 "SDEI", table_data->len - sdei_start, 1, NULL, NULL);
>> +}
> that's dummy table and doesn't match what spec describes,
> It doesn't look correct SDEI table.

Refer to below document, Appendix C, I see the definition of SDEI is 
really a dummy table, also it is said in the document: The table 
consists only of a basic header with revision 1.

http://infocenter.arm.com/help/topic/com.arm.doc.den0054a/ARM_DEN0054A_Software_Delegated_Exception_Interface.pdf

Do I miss anything?

>
>> +
>> +static void
>>   build_spcr(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
>>   {
>>       AcpiSerialPortConsoleRedirection *spcr;
>> @@ -796,6 +807,11 @@ void virt_acpi_build(VirtMachineState *vms, AcpiBuildTables *tables)
>>       acpi_add_table(table_offsets, tables_blob);
>>       build_spcr(tables_blob, tables->linker, vms);
>>   
>> +    if (sdei_enabled) {
>> +        acpi_add_table(table_offsets, tables_blob);
>> +        build_sdei(tables_blob, tables->linker, vms);
>> +    }
>> +
>>       if (ms->numa_state->num_nodes > 0) {
>>           acpi_add_table(table_offsets, tables_blob);
>>           build_srat(tables_blob, tables->linker, vms);
>> diff --git a/include/hw/acpi/acpi-defs.h b/include/hw/acpi/acpi-defs.h
>> index 57a3f58..0a2265d 100644
>> --- a/include/hw/acpi/acpi-defs.h
>> +++ b/include/hw/acpi/acpi-defs.h
>> @@ -634,4 +634,9 @@ struct AcpiIortRC {
>>   } QEMU_PACKED;
>>   typedef struct AcpiIortRC AcpiIortRC;
>>   
>> +struct AcpiSdei {
>> +    ACPI_TABLE_HEADER_DEF     /* ACPI common table header */
>> +} QEMU_PACKED;
>> +typedef struct AcpiSdei AcpiSdei;
> we don't use packed structures for ACPI anymore, see build_rsdp() for
> example of how tables are composed and comment style required for each field.
Sure; will fix it in v2.

Thanks,

Heyi

>
>>   #endif
>
> .
>