From f9f9c9d2c618c494f0d8ba9f4a1da4aea725d003 Mon Sep 17 00:00:00 2001 From: Jeremy Kerr Date: Sun, 23 May 2021 17:58:06 +0800 Subject: buspirate: Add psus option This change adds a 'psus=' option, to control the external Vcc state of the bus pirate, allowing hardware where the SPI flash chip is powered by the 3V3/5V lines directly. Change-Id: I8a7d4b40c0f7f04f6976f6757f05b61f2c9958f9 Signed-off-by: Jeremy Kerr Reviewed-on: https://review.coreboot.org/c/flashrom/+/54887 Tested-by: build bot (Jenkins) Reviewed-by: Nico Huber --- buspirate_spi.c | 16 ++++++++++++++++ flashrom.8.tmpl | 16 +++++++++++++++- 2 files changed, 31 insertions(+), 1 deletion(-) diff --git a/buspirate_spi.c b/buspirate_spi.c index 04b8fdec2..bfd0e0523 100644 --- a/buspirate_spi.c +++ b/buspirate_spi.c @@ -326,6 +326,7 @@ static int buspirate_spi_init(void) int serialspeed_index = -1; int ret = 0; int pullup = 0; + int psu = 0; unsigned char *bp_commbuf; int bp_commbufsize; @@ -377,6 +378,17 @@ static int buspirate_spi_init(void) } free(tmp); + tmp = extract_programmer_param("psus"); + if (tmp) { + if (strcasecmp("on", tmp) == 0) + psu = 1; + else if (strcasecmp("off", tmp) == 0) + ; // ignore + else + msg_perr("Invalid psus state, not enabling.\n"); + } + free(tmp); + /* Default buffer size is 19: 16 bytes data, 3 bytes control. */ #define DEFAULT_BUFSIZE (16 + 3) bp_commbuf = malloc(DEFAULT_BUFSIZE); @@ -638,6 +650,10 @@ static int buspirate_spi_init(void) bp_commbuf[0] |= (1 << 2); msg_pdbg("Enabling pull-up resistors.\n"); } + if (psu == 1) { + bp_commbuf[0] |= (1 << 3); + msg_pdbg("Enabling PSUs.\n"); + } ret = buspirate_sendrecv(bp_commbuf, 1, 1); if (ret) { ret = 1; diff --git a/flashrom.8.tmpl b/flashrom.8.tmpl index 4ae7e71bf..228e17bb5 100644 --- a/flashrom.8.tmpl +++ b/flashrom.8.tmpl @@ -952,7 +952,21 @@ can be More information about the Bus Pirate pull-up resistors and their purpose is available .URLB "http://dangerousprototypes.com/docs/Practical_guide_to_Bus_Pirate_pull-up_resistors" \ "in a guide by dangerousprototypes" . -Only the external supply voltage (Vpu) is supported as of this writing. +.sp +The state of the Bus Pirate power supply pins is controllable through an optional +.B psus +parameter. Syntax is +.sp +.B " flashrom -p buspirate_spi:psus=state" +.sp +where +.B state +can be +.BR on " or " off . +This allows the bus pirate to power the ROM chip directly. This may also be used to provide the +required pullup voltage (when using the +.B pullups +option), by connecting the Bus Pirate's Vpu input to the appropriate Vcc pin. .SS .BR "pickit2_spi " programmer .IP -- cgit v1.2.3