From 04953ebf5f343dcb37e1288705a160b4cf1b64cf Mon Sep 17 00:00:00 2001 From: Christian Walter Date: Fri, 27 Mar 2020 11:59:43 +0100 Subject: southbridge/intel/common: Add Process Call Add functionality to use process call cycle. It can be used to write/read data to/from e.g. EEPROM attached to SMBus Controller via I2C. Tested on: * C246 Change-Id: Ifdac6cf70a4ce744601f5d152a83d2125ea88360 Signed-off-by: Christian Walter Reviewed-on: https://review.coreboot.org/c/coreboot/+/39875 Reviewed-by: Patrick Rudolph Tested-by: build bot (Jenkins) --- src/southbridge/intel/common/smbus.c | 37 ++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) (limited to 'src/southbridge') diff --git a/src/southbridge/intel/common/smbus.c b/src/southbridge/intel/common/smbus.c index 95c2fd0957..8b19b7d900 100644 --- a/src/southbridge/intel/common/smbus.c +++ b/src/southbridge/intel/common/smbus.c @@ -33,6 +33,7 @@ #define I801_BYTE (1 << 2) #define I801_BYTE_DATA (2 << 2) #define I801_WORD_DATA (3 << 2) +#define I801_PROCESS_CALL (4 << 2) #define I801_BLOCK_DATA (5 << 2) #define I801_I2C_BLOCK_DATA (6 << 2) /* ICH5 and later */ @@ -391,6 +392,42 @@ int do_smbus_block_read(uintptr_t base, u8 device, u8 cmd, size_t max_bytes, u8 return ret; } +/* + * The caller is responsible of settings HOSTC I2C_EN bit prior to making this + * call! + */ +int do_smbus_process_call(uintptr_t base, u8 device, u8 cmd, u16 data, u16 *buf) +{ + int ret; + + /* Set up for process call */ + ret = setup_command(base, I801_PROCESS_CALL, XMIT_WRITE(device)); + if (ret < 0) + return ret; + + /* cmd will only be send if I2C_EN is zero */ + host_outb(base, SMBHSTCMD, cmd); + + host_outb(base, SMBHSTDAT0, data & 0x00ff); + host_outb(base, SMBHSTDAT1, (data & 0xff00) >> 8); + + /* Start the command */ + ret = execute_command(base); + if (ret < 0) + return ret; + + /* Poll for transaction completion */ + ret = complete_command(base); + if (ret < 0) + return ret; + + /* Read results of transaction */ + *buf = host_inb(base, SMBHSTDAT0); + *buf |= (host_inb(base, SMBHSTDAT1) << 8); + + return ret; +} + int do_smbus_block_write(uintptr_t base, u8 device, u8 cmd, const size_t bytes, const u8 *buf) { int ret; -- cgit v1.2.3