Re: [SeaBIOS] [PATCHv4] acpi: make default DSDT optional

[Laszlo Ersek]

On 03/18/13 14:18, Michael S. Tsirkin wrote:
> Since commit f7e4dd6c18ccfbaf6cd2f5eaaed2b77cabc8a406 QEMU loads its
> own copy of DSDT, so let's not build in PIIX.  This makes building in
> the DSDT an option, default to on (built-in).  If no one complains for a
> while, we'll be able to switch it off and then maybe remove altogether.
>
> With CONFIG_ACPI_DSDT = y
> Total size: 127348  Fixed: 58892  Free: 3724 (used 97.2% of 128KiB rom)
> With CONFIG_ACPI_DSDT = n
> Total size: 122844  Fixed: 58884  Free: 8228 (used 93.7% of 128KiB rom)
> Signed-off-by: Michael S. Tsirkin
>
> Changes from v3:
> More changes suggested by Laszlo and Kevin, missed in v2.
> Better document the new option as suggested by Paul and Kevin.
>
> Changes from v2:
>        - fixed and extended the commit log addressing comments by Gerd,
>          Laszlo, Paul. No functional changes.
>
> Changes from v1:
>        - default the new option to y to reduce
>          disruption to existing users
>
> src/Kconfig | 10 ++++++++++
>  src/acpi.c  |  3 ++-
>  2 files changed, 12 insertions(+), 1 deletion(-)
>
> diff --git a/src/Kconfig b/src/Kconfig
> index 3141069..5796173 100644
> --- a/src/Kconfig
> +++ b/src/Kconfig
> @@ -387,6 +387,16 @@ menu "BIOS Tables"
>          default y
>          help
>              Support generation of ACPI tables.
> config ACPI_DSDT
>    bool "Include default ACPI DSDT"
>    default y
>    depends on ACPI
>    help
>        Include default DSDT ACPI table in BIOS.
>        Required for QEMU 1.3 and older.
>        This option can be disabled for QEMU 1.4 and newer
>        to save some space in the ROM file.
>        If unsure, say Y.
>
> endmenu
>
> source vgasrc/Kconfig
> diff --git a/src/acpi.c b/src/acpi.c
> index 119d1c1..88abc09 100644
> --- a/src/acpi.c
> +++ b/src/acpi.c
> @@ -826,7 +826,8 @@ acpi_setup(void)
>              break;
>          }
>      }
> if (fadt && !fadt->dsdt) {
> if (CONFIG_ACPI_DSDT && fadt && !fadt->dsdt) {
>     /* default DSDT */
>     void *dsdt = malloc_high(sizeof(AmlCode));
>     if (!dsdt) {

Ah I see. We build the hex file & include it too, but gcc will optimize
it out.

Reviewed-by: Laszlo Ersek