serprog: add opcode to control the programmer's output drivers
This allowed me to let the clips remain attached on my D946GZIS while
playing with coreboot/serialice.
Corresponding to flashrom svn r1618.
Signed-off-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>
Acked-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>
diff --git a/Documentation/serprog-protocol.txt b/Documentation/serprog-protocol.txt
index 821cf28..58f4417 100644
--- a/Documentation/serprog-protocol.txt
+++ b/Documentation/serprog-protocol.txt
@@ -34,6 +34,7 @@
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
+0x15 Toggle flash chip pin drivers 8-bit (0 disable, else enable) ACK / NAK
0x?? unimplemented command - invalid.
@@ -82,6 +83,12 @@
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.
+ 0x15 (S_CMD_S_PIN_STATE):
+ Sets the state of the pin drivers connected to the flash chip. Disabling them allows other
+ devices (e.g. a mainboard's chipset) to access the chip. This way the serprog controller can
+ remain attached to the flash chip even when the board is running. The user is responsible to
+ NOT connect VCC and other permanently externally driven signals to the programmer as needed.
+ If the value is 0, then the drivers should be disabled, otherwise they should be enabled.
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.
diff --git a/serprog.c b/serprog.c
index 28faac8..edc5a7b 100644
--- a/serprog.c
+++ b/serprog.c
@@ -664,6 +664,15 @@
sp_device_opbuf_size);
}
+ if (sp_check_commandavail(S_CMD_S_PIN_STATE)) {
+ uint8_t en = 1;
+ if (sp_docommand(S_CMD_S_PIN_STATE, 1, &en, 0, NULL) != 0) {
+ msg_perr("Error: could not enable output buffers\n");
+ return 1;
+ } else
+ msg_pdbg(MSGHEADER "Output drivers enabled\n");
+ } else
+ msg_pdbg(MSGHEADER "Warning: Programmer does not support toggling its output drivers\n");
sp_prev_was_write = 0;
sp_streamed_transmit_ops = 0;
sp_streamed_transmit_bytes = 0;
@@ -736,9 +745,15 @@
static int serprog_shutdown(void *data)
{
- msg_pspew("%s\n", __func__);
if ((sp_opbuf_usage) || (sp_max_write_n && sp_write_n_bytes))
sp_execute_opbuf();
+ if (sp_check_commandavail(S_CMD_S_PIN_STATE)) {
+ uint8_t dis = 0;
+ if (sp_docommand(S_CMD_S_PIN_STATE, 1, &dis, 0, NULL) == 0)
+ msg_pdbg(MSGHEADER "Output drivers disabled\n");
+ else
+ msg_perr(MSGHEADER "%s: Warning: could not disable output buffers\n", __func__);
+ }
/* FIXME: fix sockets on windows(?), especially closing */
serialport_shutdown(&sp_fd);
if (sp_max_write_n)
diff --git a/serprog.h b/serprog.h
index 8d11772..b54aaea 100644
--- a/serprog.h
+++ b/serprog.h
@@ -22,3 +22,4 @@
#define S_CMD_S_BUSTYPE 0x12 /* Set used bustype(s). */
#define S_CMD_O_SPIOP 0x13 /* Perform SPI operation. */
#define S_CMD_S_SPI_FREQ 0x14 /* Set SPI clock frequency */
+#define S_CMD_S_PIN_STATE 0x15 /* Enable/disable output drivers */