Re: [Qemu-devel] [PATCH 3/4] acpi: stash the OEM ID and OEM Table ID fields from an external SLIC table

[Laszlo Ersek <lersek@redhat.com>]

On 01/14/16 11:21, Michael S. Tsirkin wrote:
> On Thu, Jan 14, 2016 at 02:36:56AM +0100, Laszlo Ersek wrote:
>> The SLIC table is not generated by QEMU. If the user specifies an external
>> one however, then board-specific code might want to adapt other,
>> auto-generated tables to it. This patch saves the OEM ID and OEM Table ID
>> fields from the SLIC, and leaves the actual utilization to board code (the
>> next patch).
>>
>> Cc: "Michael S. Tsirkin" <mst@redhat.com> (supporter:ACPI/SMBIOS)
>> Cc: Igor Mammedov <imammedo@redhat.com> (supporter:ACPI/SMBIOS)
>> Cc: Richard W.M. Jones <rjones@redhat.com>
>> Cc: Aleksei Kovura <alex3kov@zoho.com>
>> Cc: Michael Tokarev <mjt@tls.msk.ru>
>> RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=1248758
>> Signed-off-by: Laszlo Ersek <lersek@redhat.com>
>> ---
>>  include/hw/acpi/acpi.h |  2 ++
>>  hw/acpi/core.c         | 18 ++++++++++++++++++
>>  2 files changed, 20 insertions(+)
>>
>> diff --git a/include/hw/acpi/acpi.h b/include/hw/acpi/acpi.h
>> index b20bd55..407197a 100644
>> --- a/include/hw/acpi/acpi.h
>> +++ b/include/hw/acpi/acpi.h
>> @@ -189,6 +189,8 @@ void acpi_update_sci(ACPIREGS *acpi_regs, qemu_irq irq);
>>  extern int acpi_enabled;
>>  extern char unsigned *acpi_tables;
>>  extern size_t acpi_tables_len;
>> +extern char *acpi_slic_oem_id;
>> +extern char *acpi_slic_oem_table_id;
>>  
>>  uint8_t *acpi_table_first(void);
>>  uint8_t *acpi_table_next(uint8_t *current);
> 
> This seems rather messy.
> How about an API to find SLIC and return the IDs
> from the installed tables?

If testing confirms this idea is worthwhile, I won't object to your
suggestion. I admit I don't readily recall how the externally provided
tables are represented in that big concatenated blob, but perhaps I can
look at acpi_table_first() / acpi_table_next(). (Or just stare at the
code longer.)

So: fair enough, thanks.

Laszlo

> 
>> diff --git a/hw/acpi/core.c b/hw/acpi/core.c
>> index 21e113d..7046035 100644
>> --- a/hw/acpi/core.c
>> +++ b/hw/acpi/core.c
>> @@ -54,6 +54,8 @@ static const char unsigned dfl_hdr[ACPI_TABLE_HDR_SIZE - ACPI_TABLE_PFX_SIZE] =
>>  
>>  char unsigned *acpi_tables;
>>  size_t acpi_tables_len;
>> +char *acpi_slic_oem_id;
>> +char *acpi_slic_oem_table_id;
>>  
>>  static QemuOptsList qemu_acpi_opts = {
>>      .name = "acpi",
>> @@ -227,6 +229,22 @@ static void acpi_table_install(const char unsigned *blob, size_t bloblen,
>>      /* recalculate checksum */
>>      ext_hdr->checksum = acpi_checksum((const char unsigned *)ext_hdr +
>>                                        ACPI_TABLE_PFX_SIZE, acpi_payload_size);
>> +
>> +    /* If the table signature is SLIC, stash the OEM ID and OEM Table ID
>> +     * fields, so we can later adapt the RSDT and the FADT.
>> +     */
>> +    if (memcmp(ext_hdr->sig, "SLIC", 4) == 0) {
>> +        g_free(acpi_slic_oem_id);
>> +        acpi_slic_oem_id = g_malloc(sizeof ext_hdr->oem_id + 1);
>> +        memcpy(acpi_slic_oem_id, ext_hdr->oem_id, sizeof ext_hdr->oem_id);
>> +        acpi_slic_oem_id[sizeof ext_hdr->oem_id] = '\0';
>> +
>> +        g_free(acpi_slic_oem_table_id);
>> +        acpi_slic_oem_table_id = g_malloc(sizeof ext_hdr->oem_table_id + 1);
>> +        memcpy(acpi_slic_oem_table_id, ext_hdr->oem_table_id,
>> +               sizeof ext_hdr->oem_table_id);
>> +        acpi_slic_oem_table_id[sizeof ext_hdr->oem_table_id] = '\0';
>> +    }
>>  }
>>  
>>  void acpi_table_add(const QemuOpts *opts, Error **errp)
>> -- 
>> 1.8.3.1
>>