On Tue, Apr 23, 2013 at 06:22:12PM +0300, Michael S. Tsirkin wrote:
So here's the version with shift, that should do it correctly. Add mere 8 lines of code. I'll look into alignment and fseg now.
[...]
--- /dev/null +++ b/src/linker.h @@ -0,0 +1,29 @@ +#include "types.h" // u8 +#include "util.h" // romfile_s
+/* ROM file linker interface. Linker uses little endian format */ +struct linker_entry_s {
- u8 size; /* size in bytes including the header */
- u8 bytes; /* How many bytes to change. Can be 1,2,4 or 8. */
- u8 shift; /* Shift source address right by this many bits. 0-63. */
- u8 type;
- u8 format;
- u8 reserved1;
- u16 reserved2;
- u64 dst_offset; /* Offset in destination. Little endian format. */
- /* Followed by source and destination, optionally padded by
* 0, up to the total of entry_len - 4 bytes.* Strings are 0-terminated. */- char src_dst[];
+} PACKED;
As in my previous email, I think the main emphasis should be on getting the content into QEMU, so I don't want to nitpick on the details of the seabios side. However, if I understand your proposal, an RSDT with 10 table entries would require 50 "linker" entries (10 to add the pointers and 40 to update the checksum) - that seems excessive. If the goal is to do a checksum - might as well just define a checksum action. Also, the variable length filenames aren't needed - the QemuCfgFile interface already limits the filename to a max of 56 bytes.
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; };
// COMMAND_CHECKSUM - Update a checksum in a table struct { char cksum_file[FILESZ]; u32 cksum_offset; u32 cksum_start; u32 cksum_length; };
// PAD char pad[124]; }; } PACKED;
-Kevin