diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/southbridge/intel/common/smbus.c | 58 |
1 files changed, 43 insertions, 15 deletions
diff --git a/src/southbridge/intel/common/smbus.c b/src/southbridge/intel/common/smbus.c index cac9ba7943..ee58aab995 100644 --- a/src/southbridge/intel/common/smbus.c +++ b/src/southbridge/intel/common/smbus.c @@ -17,6 +17,7 @@ #include <arch/io.h> #include <device/smbus_def.h> +#include <stdlib.h> #include "smbus.h" @@ -193,14 +194,17 @@ int do_smbus_write_byte(unsigned int smbus_base, u8 device, } int do_smbus_block_read(unsigned int smbus_base, u8 device, u8 cmd, - unsigned int bytes, u8 *buf) + unsigned int max_bytes, u8 *buf) { u8 status; + int slave_bytes; int bytes_read = 0; unsigned int loops = SMBUS_TIMEOUT; if (smbus_wait_until_ready(smbus_base) < 0) return SMBUS_WAIT_UNTIL_READY_TIMEOUT; + max_bytes = MIN(32, max_bytes); + /* Set up transaction */ /* Disable interrupts */ outb(inb(smbus_base + SMBHSTCTL) & ~SMBHSTCNT_INTREN, @@ -210,11 +214,15 @@ int do_smbus_block_read(unsigned int smbus_base, u8 device, u8 cmd, /* Set the command/address... */ outb(cmd & 0xff, smbus_base + SMBHSTCMD); /* Set up for a block data read */ - outb((inb(smbus_base + SMBHSTCTL) & 0xe3) | I801_BLOCK_DATA, + outb((inb(smbus_base + SMBHSTCTL) & 0xc3) | I801_BLOCK_DATA, (smbus_base + SMBHSTCTL)); /* Clear any lingering errors, so the transaction will run */ outb(inb(smbus_base + SMBHSTSTAT), smbus_base + SMBHSTSTAT); + /* Reset number of bytes to transfer so we notice later it + * was really updated with the transaction. */ + outb(0, smbus_base + SMBHSTDAT0); + /* Start the command */ outb((inb(smbus_base + SMBHSTCTL) | SMBHSTCNT_START), smbus_base + SMBHSTCTL); @@ -233,28 +241,39 @@ int do_smbus_block_read(unsigned int smbus_base, u8 device, u8 cmd, return SMBUS_ERROR; if (status & SMBHSTSTS_BYTE_DONE) { /* Byte done */ - *buf = inb(smbus_base + SMBBLKDAT); - buf++; - bytes_read++; - if (--bytes == 1) { - /* indicate that next byte is the last one */ - outb(inb(smbus_base + SMBHSTCTL) - | SMBHSTCNT_LAST_BYTE, - smbus_base + SMBHSTCTL); + + if (bytes_read < max_bytes) { + *buf = inb(smbus_base + SMBBLKDAT); + buf++; + bytes_read++; } + + /* Engine internally completes the transaction + * and clears HOST_BUSY flag once the byte count + * from slave is reached. + */ outb(status, smbus_base + SMBHSTSTAT); } } while ((status & SMBHSTSTS_HOST_BUSY) && loops); + /* Post-check we received complete message. */ + slave_bytes = inb(smbus_base + SMBHSTDAT0); + if (bytes_read < slave_bytes) + return SMBUS_ERROR; + return bytes_read; } int do_smbus_block_write(unsigned int smbus_base, u8 device, u8 cmd, - unsigned int bytes, const u8 *buf) + const unsigned int bytes, const u8 *buf) { u8 status; + int bytes_sent = 0; unsigned int loops = SMBUS_TIMEOUT; + if (bytes > 32) + return SMBUS_ERROR; + if (smbus_wait_until_ready(smbus_base) < 0) return SMBUS_WAIT_UNTIL_READY_TIMEOUT; @@ -267,7 +286,7 @@ int do_smbus_block_write(unsigned int smbus_base, u8 device, u8 cmd, /* Set the command/address... */ outb(cmd & 0xff, smbus_base + SMBHSTCMD); /* Set up for a block data write */ - outb((inb(smbus_base + SMBHSTCTL) & 0xe3) | I801_BLOCK_DATA, + outb((inb(smbus_base + SMBHSTCTL) & 0xc3) | I801_BLOCK_DATA, (smbus_base + SMBHSTCTL)); /* Clear any lingering errors, so the transaction will run */ outb(inb(smbus_base + SMBHSTSTAT), smbus_base + SMBHSTSTAT); @@ -275,8 +294,10 @@ int do_smbus_block_write(unsigned int smbus_base, u8 device, u8 cmd, /* set number of bytes to transfer */ outb(bytes, smbus_base + SMBHSTDAT0); + /* Send first byte from buffer, bytes_sent increments after + * hardware acknowledges it. + */ outb(*buf++, smbus_base + SMBBLKDAT); - bytes--; /* Start the command */ outb((inb(smbus_base + SMBHSTCTL) | SMBHSTCNT_START), @@ -296,12 +317,19 @@ int do_smbus_block_write(unsigned int smbus_base, u8 device, u8 cmd, return SMBUS_ERROR; if (status & SMBHSTSTS_BYTE_DONE) { - outb(*buf++, smbus_base + SMBBLKDAT); + bytes_sent++; + if (bytes_sent < bytes) + outb(*buf++, smbus_base + SMBBLKDAT); + + /* Engine internally completes the transaction + * and clears HOST_BUSY flag once the byte count + * has been reached. + */ outb(status, smbus_base + SMBHSTSTAT); } } while ((status & SMBHSTSTS_HOST_BUSY) && loops); - return 0; + return bytes_sent; } /* Only since ICH5 */ |