Re: [SeaBIOS] [PATCH 2/2] accept MADT over fw_cfg

[Kevin O'Connor]

On Tue, May 07, 2013 at 07:33:13PM +0300, Michael S. Tsirkin wrote:
> > If you really feel QEMU should direct the pointer and checksum
> > updates, you might want to consider something like:
> >
> > struct tabledeploy_s {
> >     u32 command;
> >     union {
> >         // COMMAND_ALLOC - allocate a table from the given "file"
> >         struct {
> >             char alloc_file[FILESZ];
> >             u32 alloc_align;
> >             u8 alloc_zone;
> >         };
> >     // COMMAND_PATCH - patch the table (originating from
> >     // "dest_file") to a pointer to the table originating from
> >     // "src_file".
> >     struct {
> >         char patch_dest_file[FILESZ];
> >         char patch_src_file[FILESZ];
> >         u32 patch_offset;
> >         u8 patch_size;
> >     };
>
> I think ADD is better since this way we can use not the start of table,
> but something in the middle. For example, a single fw_cfg can give us
> multiple tables, it should be up to QEMU.
>
> It's equivalent to PATCH if the original data is 0.
> >     // COMMAND_CHECKSUM - Update a checksum in a table
> >     struct {
> >         char cksum_file[FILESZ];
> >         u32 cksum_offset;
> >         u32 cksum_start;
> >         u32 cksum_length;
> >     };
>
> Same here. So I would do:
>
> COMMAND_ADD_POINTER
>
> COMMAND_ADD_CHECKSUM

That's fine.

-Kevin