Re: [Qemu-devel] E820 (Re: [v4 PATCH 00/12] SMBIOS: build full tables in QEMU)

[Gabriel L. Somlo]

On Mon, Apr 07, 2014 at 11:23:44AM -0400, Kevin O'Connor wrote:
> So, I'm suggesting QEMU produce two new fw_cfg files: an anchor file
> with the valid anchor table (the address pointer can be just set to
> zero), and an smbios table file with the complete set of smbios tables
> formatted according to the smbios spec.  SeaBIOS can then use the
> existence of one of these new files to determine if it should deploy
> (and optionally modify) them or if it should use the old smbios
> generation code.

Oh, OK. Right now we have (in qemu):

#define SMBIOS_FIELD_ENTRY 0
#define SMBIOS_TABLE_ENTRY 1

I will be adding (actually, migrating to):

#define SMBIOS_ANCHOR_ENTRY 2 /* for the smbios entry point table */
#define SMBIOS_FULLTABLE_ENTRY 3 /* for the blob containing all types */

The cool thing here is that, along with the payload for each type, I
can create a wrapper structure, like there already exists for fields
and individual table types:

struct smbios_field {
    struct smbios_header header;
    uint8_t type;
    uint16_t offset;
    uint8_t data[];
} QEMU_PACKED;

struct smbios_table {
    struct smbios_header header;
    uint8_t data[];
} QEMU_PACKED;

I can add such a structure for the anchor/entrypoint table and for the
full blob-of-tables payload, in which I can tell you how big type 0 is,
so the BIOS (SeaBIOS/TianoCore) side surgery can be made that much
easier...

Thanks,
--Gabriel