mirror of
https://review.coreboot.org/flashrom.git
synced 2025-04-26 22:52:34 +02:00
0d82e952f2
Corresponding to flashrom svn r1617. Signed-off-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at> Acked-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>
96 lines
4.8 KiB
Plaintext
96 lines
4.8 KiB
Plaintext
Serial Flasher Protocol Specification - version 1 (0x01 return value == 1)
|
|
|
|
Command And Answer Sequence - all commands give an answer.
|
|
PC: COMMAND(8bit) <parameters determined by opcode>
|
|
DEV: ACK/NAK(8bit) <OPTIONAL RETURN BYTES (only if ACK)> / nothing
|
|
Command 0x10 (SYNCNOP) has a special return of NAK+ACK for synchronization.
|
|
|
|
ACK = 0x06
|
|
NAK = 0x15
|
|
|
|
All multibyte values are little-endian. Addresses and lengths are 24-bit.
|
|
|
|
COMMAND Description Parameters Return Value
|
|
0x00 NOP none ACK
|
|
0x01 Query programmer iface version none ACK + 16bit version (nonzero)
|
|
0x02 Query supported commands bitmap none ACK + 32 bytes (256 bits) of supported cmds flags
|
|
0x03 Query programmer name none ACK + 16 bytes string (null padding) / NAK
|
|
0x04 Query serial buffer size none ACK + 16bit size / NAK
|
|
0x05 Query supported bustypes none ACK + 8-bit flags (as per flashrom) / NAK
|
|
0x06 Query connected address lines none ACK + 8bit line count / NAK
|
|
0x07 Query operation buffer size none ACK + 16bit size / NAK
|
|
0x08 Query maximum write-n length none ACK + 24bit length (0==2^24) / NAK
|
|
0x09 Read byte 24-bit addr ACK + BYTE / NAK
|
|
0x0A Read n bytes 24-bit addr + 24-bit length ACK + length bytes / NAK
|
|
0x0B Initialize operation buffer none ACK / NAK
|
|
0x0C Write to opbuf: Write byte 24-bit addr + 8-bit byte ACK / NAK (NOTE: takes 5 bytes in opbuf)
|
|
0x0D Write to opbuf: Write n 24-bit length + 24-bit addr + ACK / NAK (NOTE: takes 7+n bytes in opbuf)
|
|
+ length bytes of data
|
|
0x0E Write to opbuf: delay 32-bit usecs ACK / NAK (NOTE: takes 5 bytes in opbuf)
|
|
0x0F Execute operation buffer none ACK / NAK
|
|
0x10 Sync NOP none NAK + ACK (for synchronization)
|
|
0x11 Query maximum read-n length none ACK + 24-bit length (0==2^24) / NAK
|
|
0x12 Set used bustype 8-bit flags (as with 0x05) ACK / NAK
|
|
0x13 Perform SPI operation 24-bit slen + 24-bit rlen ACK + rlen bytes of data / NAK
|
|
+ slen bytes of data
|
|
0x14 Set SPI clock frequency in Hz 32-bit requested frequency ACK + 32-bit set frequency / NAK
|
|
0x?? unimplemented command - invalid.
|
|
|
|
|
|
Additional information of the above commands:
|
|
About unimplemented commands / startup sequence:
|
|
Only commands allowed to be used without checking anything are 0x00,0x10 and 0x01 (NOP,SYNCNOP,Q_IFACE).
|
|
If 0x01 doesn't return 1, dont do anything if you dont support a newer protocol.
|
|
Then, check support for any other opcode (except 0x02) by using 0x02 (Q_CMDMAP).
|
|
0x02 (Q_CMDMAP):
|
|
The map's bits are mapped as follows:
|
|
cmd 0 support: byte 0 bit 0
|
|
cmd 1 support: byte 0 bit 1
|
|
cmd 7 support: byte 0 bit 7
|
|
cmd 8 support: byte 1 bit 0, and so on.
|
|
0x04 (Q_SERBUF):
|
|
If the programmer has a guaranteed working flow control,
|
|
it should return a big bogus value - eg 0xFFFF.
|
|
0x05 (Q_BUSTYPE):
|
|
The bit's are defined as follows:
|
|
bit 0: PARALLEL, bit 1: LPC, bit 2: FWH, bit 3: SPI.
|
|
0x06 (Q_CHIPSIZE):
|
|
Only applicable to parallel programmers.
|
|
An LPC/FWH/SPI-programmer can report this as not supported in the command bitmap.
|
|
0x08 (Q_WRNMAXLEN):
|
|
If a programmer reports a bigger maximum write-n length than the serial buffer size,
|
|
it is assumed that the programmer can process the data fast enough to take in the
|
|
reported maximum write-n without problems.
|
|
0x0F (O_EXEC):
|
|
Execute operation buffer will also clear it, regardless of the return value.
|
|
0x11 (Q_RDNMAXLEN):
|
|
If this command is not supported, assume return of 0 (2^24).
|
|
0x12 (S_BUSTYPE):
|
|
Set's the used bustype if the programmer can support more than one flash protocol.
|
|
Sending a byte with more than 1 bit set will make the programmer decide among them
|
|
on it's own. Bit values as with Q_BUSTYPE.
|
|
0x13 (O_SPIOP):
|
|
Send and receive bytes via SPI.
|
|
Maximum slen is Q_WRNMAXLEN in case Q_BUSTYPE returns SPI only or S_BUSTYPE was used
|
|
to set SPI exclusively before. Same for rlen and Q_RDNMAXLEN.
|
|
This operation is immediate, meaning it doesnt use the operation buffer.
|
|
0x14 (S_SPI_FREQ):
|
|
Set the SPI clock frequency. The 32-bit value indicates the
|
|
requested frequency in Hertz. Value 0 is reserved and should
|
|
be NAKed by the programmer. The requested frequency should be
|
|
mapped by the programmer software to a supported frequency
|
|
lower than the one requested. If there is no lower frequency
|
|
available the lowest possible should be used. The value
|
|
chosen is sent back in the reply with an ACK.
|
|
About mandatory commands:
|
|
The only truly mandatory commands for any device are 0x00, 0x01, 0x02 and 0x10,
|
|
but one can't really do anything with these commands.
|
|
Support for the following commands is necessary for flashrom to operate properly:
|
|
S_CMD_Q_SERBUF, S_CMD_Q_OPBUF, S_CMD_Q_WRNMAXLEN, S_CMD_R_BYTE,
|
|
S_CMD_R_NBYTES, S_CMD_O_INIT, S_CMD_O_WRITEB, S_CMD_O_WRITEN,
|
|
S_CMD_O_DELAY, S_CMD_O_EXEC.
|
|
In addition, support for these commands is recommended:
|
|
S_CMD_Q_PGMNAME, S_CMD_Q_BUSTYPE, S_CMD_Q_CHIPSIZE (if parallel).
|
|
|
|
See also serprog.h.
|