From c38d543feb9491bc848138ca01a59cb25889d160 Mon Sep 17 00:00:00 2001 From: Kyösti Mälkki Date: Sun, 20 Aug 2017 21:36:18 +0300 Subject: sb/intel/common: SMBus complete_command() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Adds helper to test for SMBHSTSTAT flags for hardware having finished or failed a transaction. Change-Id: Idea15e03edde7aeedf198c1529f09c24a5bc0b06 Signed-off-by: Kyösti Mälkki Reviewed-on: https://review.coreboot.org/c/21120 Tested-by: build bot (Jenkins) Reviewed-by: Arthur Heymans --- src/southbridge/intel/common/smbus.c | 119 +++++++++++++++++++---------------- 1 file changed, 65 insertions(+), 54 deletions(-) (limited to 'src/southbridge/intel/common/smbus.c') diff --git a/src/southbridge/intel/common/smbus.c b/src/southbridge/intel/common/smbus.c index fb7f8e5754..1302798e06 100644 --- a/src/southbridge/intel/common/smbus.c +++ b/src/southbridge/intel/common/smbus.c @@ -65,6 +65,14 @@ static void smbus_delay(void) inb(0x80); } +static int host_completed(u8 status) +{ + if (status & SMBHSTSTS_HOST_BUSY) + return 0; + status &= ~(SMBHSTSTS_SMBALERT_STS | SMBHSTSTS_INUSE_STS); + return status != 0; +} + static int recover_master(int smbus_base, int ret) { /* TODO: Depending of the failure, drive KILL transaction @@ -74,6 +82,17 @@ static int recover_master(int smbus_base, int ret) return ret; } +static int cb_err_from_stat(u8 status) +{ + /* Ignore the "In Use" status... */ + status &= ~(SMBHSTSTS_SMBALERT_STS | SMBHSTSTS_INUSE_STS); + + if (status == SMBHSTSTS_INTR) + return 0; + + return SMBUS_ERROR; +} + static int setup_command(unsigned int smbus_base, u8 ctrl, u8 xmitadd) { unsigned int loops = SMBUS_TIMEOUT; @@ -128,26 +147,28 @@ static int execute_command(unsigned int smbus_base) return 0; } -static int smbus_wait_until_done(u16 smbus_base) +static int complete_command(unsigned int smbus_base) { unsigned int loops = SMBUS_TIMEOUT; - unsigned char byte; + u8 status; + do { smbus_delay(); - if (--loops == 0) - break; - byte = inb(smbus_base + SMBHSTSTAT); - } while ((byte & SMBHSTSTS_HOST_BUSY) - || (byte & ~(SMBHSTSTS_INUSE_STS | SMBHSTSTS_HOST_BUSY)) == 0); - return loops ? 0 : -1; + status = inb(smbus_base + SMBHSTSTAT); + } while (--loops && !host_completed(status)); + + if (loops == 0) + return recover_master(smbus_base, + SMBUS_WAIT_UNTIL_DONE_TIMEOUT); + + return cb_err_from_stat(status); } int do_smbus_read_byte(unsigned int smbus_base, u8 device, unsigned int address) { int ret; - unsigned char status; - unsigned char byte; + u8 byte; /* Set up for a byte data read. */ ret = setup_command(smbus_base, I801_BYTE_DATA, XMIT_READ(device)); @@ -166,25 +187,18 @@ int do_smbus_read_byte(unsigned int smbus_base, u8 device, return ret; /* Poll for transaction completion */ - if (smbus_wait_until_done(smbus_base) < 0) - return SMBUS_WAIT_UNTIL_DONE_TIMEOUT; - - status = inb(smbus_base + SMBHSTSTAT); - - /* Ignore the "In Use" status... */ - status &= ~(SMBHSTSTS_SMBALERT_STS | SMBHSTSTS_INUSE_STS); + ret = complete_command(smbus_base); + if (ret < 0) + return ret; /* Read results of transaction */ byte = inb(smbus_base + SMBHSTDAT0); - if (status != SMBHSTSTS_INTR) - return SMBUS_ERROR; return byte; } int do_smbus_write_byte(unsigned int smbus_base, u8 device, unsigned int address, unsigned int data) { - unsigned char status; int ret; /* Set up for a byte data write. */ @@ -204,19 +218,7 @@ int do_smbus_write_byte(unsigned int smbus_base, u8 device, return ret; /* Poll for transaction completion */ - if (smbus_wait_until_done(smbus_base) < 0) - return SMBUS_WAIT_UNTIL_DONE_TIMEOUT; - - status = inb(smbus_base + SMBHSTSTAT); - - /* Ignore the "In Use" status... */ - status &= ~(SMBHSTSTS_SMBALERT_STS | SMBHSTSTS_INUSE_STS); - - /* Read results of transaction */ - if (status != SMBHSTSTS_INTR) - return SMBUS_ERROR; - - return 0; + return complete_command(smbus_base); } int do_smbus_block_read(unsigned int smbus_base, u8 device, u8 cmd, @@ -248,12 +250,7 @@ int do_smbus_block_read(unsigned int smbus_base, u8 device, u8 cmd, /* Poll for transaction completion */ do { - loops--; status = inb(smbus_base + SMBHSTSTAT); - if (status & (SMBHSTSTS_FAILED | /* FAILED */ - SMBHSTSTS_BUS_ERR | /* BUS ERR */ - SMBHSTSTS_DEV_ERR)) /* DEV ERR */ - return SMBUS_ERROR; if (status & SMBHSTSTS_BYTE_DONE) { /* Byte done */ @@ -266,9 +263,9 @@ int do_smbus_block_read(unsigned int smbus_base, u8 device, u8 cmd, * and clears HOST_BUSY flag once the byte count * from slave is reached. */ - outb(status, smbus_base + SMBHSTSTAT); + outb(SMBHSTSTS_BYTE_DONE, smbus_base + SMBHSTSTAT); } - } while ((status & SMBHSTSTS_HOST_BUSY) && loops); + } while (--loops && !host_completed(status)); /* Post-check we received complete message. */ slave_bytes = inb(smbus_base + SMBHSTDAT0); @@ -276,6 +273,14 @@ int do_smbus_block_read(unsigned int smbus_base, u8 device, u8 cmd, dprintk("%s: status = %02x, len = %d / %d, loops = %d\n", __func__, status, bytes_read, slave_bytes, loops); + if (loops == 0) + return recover_master(smbus_base, + SMBUS_WAIT_UNTIL_DONE_TIMEOUT); + + ret = cb_err_from_stat(status); + if (ret < 0) + return ret; + if (bytes_read < slave_bytes) return SMBUS_ERROR; @@ -315,12 +320,7 @@ int do_smbus_block_write(unsigned int smbus_base, u8 device, u8 cmd, /* Poll for transaction completion */ do { - loops--; status = inb(smbus_base + SMBHSTSTAT); - if (status & (SMBHSTSTS_FAILED | /* FAILED */ - SMBHSTSTS_BUS_ERR | /* BUS ERR */ - SMBHSTSTS_DEV_ERR)) /* DEV ERR */ - return SMBUS_ERROR; if (status & SMBHSTSTS_BYTE_DONE) { bytes_sent++; @@ -331,13 +331,21 @@ int do_smbus_block_write(unsigned int smbus_base, u8 device, u8 cmd, * and clears HOST_BUSY flag once the byte count * has been reached. */ - outb(status, smbus_base + SMBHSTSTAT); + outb(SMBHSTSTS_BYTE_DONE, smbus_base + SMBHSTSTAT); } - } while ((status & SMBHSTSTS_HOST_BUSY) && loops); + } while (--loops && !host_completed(status)); dprintk("%s: status = %02x, len = %d / %d, loops = %d\n", __func__, status, bytes_sent, bytes, loops); + if (loops == 0) + return recover_master(smbus_base, + SMBUS_WAIT_UNTIL_DONE_TIMEOUT); + + ret = cb_err_from_stat(status); + if (ret < 0) + return ret; + if (bytes_sent < bytes) return SMBUS_ERROR; @@ -373,12 +381,7 @@ int do_i2c_block_read(unsigned int smbus_base, u8 device, /* Poll for transaction completion */ do { - loops--; status = inb(smbus_base + SMBHSTSTAT); - if (status & (SMBHSTSTS_FAILED | /* FAILED */ - SMBHSTSTS_BUS_ERR | /* BUS ERR */ - SMBHSTSTS_DEV_ERR)) /* DEV ERR */ - return SMBUS_ERROR; if (status & SMBHSTSTS_BYTE_DONE) { @@ -394,13 +397,21 @@ int do_i2c_block_read(unsigned int smbus_base, u8 device, smbus_base + SMBHSTCTL); } - outb(status, smbus_base + SMBHSTSTAT); + outb(SMBHSTSTS_BYTE_DONE, smbus_base + SMBHSTSTAT); } - } while ((status & SMBHSTSTS_HOST_BUSY) && loops); + } while (--loops && !host_completed(status)); dprintk("%s: status = %02x, len = %d / %d, loops = %d\n", __func__, status, bytes_read, bytes, loops); + if (loops == 0) + return recover_master(smbus_base, + SMBUS_WAIT_UNTIL_DONE_TIMEOUT); + + ret = cb_err_from_stat(status); + if (ret < 0) + return ret; + if (bytes_read < bytes) return SMBUS_ERROR; -- cgit v1.2.3