Re: [RFC v2 14/14] virt/acpi: add SDEI table if SDEI is enabled

From: Guoheyi <guoheyi@huawei.com>
To: Igor Mammedov <imammedo@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>,
	Peter Maydell <peter.maydell@linaro.org>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	Marc Zyngier <marc.zyngier@arm.com>,
	qemu-devel@nongnu.org, Shannon Zhao <shannon.zhaosl@gmail.com>,
	qemu-arm@nongnu.org, James Morse <james.morse@arm.com>,
	wanghaibin.wang@huawei.com, Dave Martin <Dave.Martin@arm.com>
Subject: Re: [RFC v2 14/14] virt/acpi: add SDEI table if SDEI is enabled
Date: Mon, 18 Nov 2019 14:44:31 +0800	[thread overview]
Message-ID: <9f032ccc-ae43-3710-daa8-445c6069903e@huawei.com> (raw)
In-Reply-To: <20191112155253.543e15ad@redhat.com>


On 2019/11/12 22:52, Igor Mammedov wrote:
> On Tue, 5 Nov 2019 17:10:56 +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>
>> ---
>>
>> Notes:
>>      v2:
>>      - Drop SDEI table definition and add comments
>>
>>   hw/arm/virt-acpi-build.c | 26 ++++++++++++++++++++++++++
>>   1 file changed, 26 insertions(+)
>>
>> diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c
>> index 4cd50175e0..73d3f8cd15 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 +476,26 @@ build_iort(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
>>                    "IORT", table_data->len - iort_start, 0, NULL, NULL);
>>   }
>>   
>> +/*
>> + * ACPI spec 6.2 Software Delegated Exception Interface (SDEI).
>> + * (Revision 1.0)
>> + * "SDEI" was reserved in ACPI 6.2. See "Links to ACPI-Related Documents"
>> + * (http://uefi.org/acpi) under the heading "Software
>> + * Delegated Exceptions Interface." The definition is under
>> + * "10 Appendix C: ACPI table definitions for SDEI" in the linked document.
>> + *
>> + * This is a dummy table to expose platform SDEI capbility to OS.
>> + */
>> +static void
>> +build_sdei(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
>> +{
>> +    int sdei_start = table_data->len;
>> +
>> +    (void)acpi_data_push(table_data, sizeof(AcpiTableHeader));
>> +    build_header(linker, table_data, (void *)(table_data->data + sdei_start),
>> +                 "SDEI", table_data->len - sdei_start, 1, NULL, NULL);
>> +}
>> +
>>   static void
>>   build_spcr(GArray *table_data, BIOSLinker *linker, VirtMachineState *vms)
>>   {
>> @@ -825,6 +846,11 @@ 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) {
> globals shouldn't be introduced in new code
OK. For this feature depends on KVM, does it make sense to add a flag to 
struct VirtMachineState?

Thanks,
HG
>
>> +        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);
>
> .
>