diff options
Diffstat (limited to 'hw/i2c')
| -rw-r--r-- | hw/i2c/pm_smbus.c | 86 |
1 files changed, 67 insertions, 19 deletions
diff --git a/hw/i2c/pm_smbus.c b/hw/i2c/pm_smbus.c index 6cfb7eb1b3..81d2a425ec 100644 --- a/hw/i2c/pm_smbus.c +++ b/hw/i2c/pm_smbus.c @@ -118,19 +118,30 @@ static void smb_transaction(PMSMBus *s) } break; case PROT_I2C_BLOCK_READ: - if (read) { - int xfersize = s->smb_data0; - if (xfersize > sizeof(s->smb_data)) { - xfersize = sizeof(s->smb_data); - } - ret = smbus_read_block(bus, addr, s->smb_data1, s->smb_data, - xfersize, false, true); - goto data8; - } else { - /* The manual says the behavior is undefined, just set DEV_ERR. */ + /* According to the Linux i2c-i801 driver: + * NB: page 240 of ICH5 datasheet shows that the R/#W + * bit should be cleared here, even when reading. + * However if SPD Write Disable is set (Lynx Point and later), + * the read will fail if we don't set the R/#W bit. + * So at least Linux may or may not set the read bit here. + * So just ignore the read bit for this command. + */ + if (i2c_start_transfer(bus, addr, 0)) { goto error; } - break; + ret = i2c_send(bus, s->smb_data1); + if (ret) { + goto error; + } + if (i2c_start_transfer(bus, addr, 1)) { + goto error; + } + s->in_i2c_block_read = true; + s->smb_blkdata = i2c_recv(s->smbus); + s->op_done = false; + s->smb_stat |= STS_HOST_BUSY | STS_BYTE_DONE; + goto out; + case PROT_BLOCK_DATA: if (read) { ret = smbus_read_block(bus, addr, cmd, s->smb_data, @@ -208,6 +219,7 @@ static void smb_transaction_start(PMSMBus *s) { if (s->smb_ctl & CTL_INTREN) { smb_transaction(s); + s->start_transaction_on_status_read = false; } else { /* Do not execute immediately the command; it will be * executed when guest will read SMB_STAT register. This @@ -217,6 +229,7 @@ static void smb_transaction_start(PMSMBus *s) * checking for status. If STS_HOST_BUSY doesn't get * set, it gets stuck. */ s->smb_stat |= STS_HOST_BUSY; + s->start_transaction_on_status_read = true; } } @@ -226,19 +239,38 @@ smb_irq_value(PMSMBus *s) return ((s->smb_stat & ~STS_HOST_BUSY) != 0) && (s->smb_ctl & CTL_INTREN); } +static bool +smb_byte_by_byte(PMSMBus *s) +{ + if (s->op_done) { + return false; + } + if (s->in_i2c_block_read) { + return true; + } + return !(s->smb_auxctl & AUX_BLK); +} + static void smb_ioport_writeb(void *opaque, hwaddr addr, uint64_t val, unsigned width) { PMSMBus *s = opaque; + uint8_t clear_byte_done; SMBUS_DPRINTF("SMB writeb port=0x%04" HWADDR_PRIx " val=0x%02" PRIx64 "\n", addr, val); switch(addr) { case SMBHSTSTS: + clear_byte_done = s->smb_stat & val & STS_BYTE_DONE; s->smb_stat &= ~(val & ~STS_HOST_BUSY); - if (!s->op_done && !(s->smb_auxctl & AUX_BLK)) { + if (clear_byte_done && smb_byte_by_byte(s)) { uint8_t read = s->smb_addr & 0x01; + if (s->in_i2c_block_read) { + /* See comment below PROT_I2C_BLOCK_READ above. */ + read = 1; + } + s->smb_index++; if (s->smb_index >= PM_SMBUS_MAX_MSG_SIZE) { s->smb_index = 0; @@ -268,12 +300,23 @@ static void smb_ioport_writeb(void *opaque, hwaddr addr, uint64_t val, s->smb_stat |= STS_BYTE_DONE; } else if (s->smb_ctl & CTL_LAST_BYTE) { s->op_done = true; - s->smb_blkdata = s->smb_data[s->smb_index]; + if (s->in_i2c_block_read) { + s->in_i2c_block_read = false; + s->smb_blkdata = i2c_recv(s->smbus); + i2c_nack(s->smbus); + i2c_end_transfer(s->smbus); + } else { + s->smb_blkdata = s->smb_data[s->smb_index]; + } s->smb_index = 0; s->smb_stat |= STS_INTR; s->smb_stat &= ~STS_HOST_BUSY; } else { - s->smb_blkdata = s->smb_data[s->smb_index]; + if (s->in_i2c_block_read) { + s->smb_blkdata = i2c_recv(s->smbus); + } else { + s->smb_blkdata = s->smb_data[s->smb_index]; + } s->smb_stat |= STS_BYTE_DONE; } } @@ -284,6 +327,10 @@ static void smb_ioport_writeb(void *opaque, hwaddr addr, uint64_t val, if (!s->op_done) { s->smb_index = 0; s->op_done = true; + if (s->in_i2c_block_read) { + s->in_i2c_block_read = false; + i2c_end_transfer(s->smbus); + } } smb_transaction_start(s); } @@ -337,8 +384,9 @@ static uint64_t smb_ioport_readb(void *opaque, hwaddr addr, unsigned width) switch(addr) { case SMBHSTSTS: val = s->smb_stat; - if (s->smb_stat & STS_HOST_BUSY) { + if (s->start_transaction_on_status_read) { /* execute command now */ + s->start_transaction_on_status_read = false; s->smb_stat &= ~STS_HOST_BUSY; smb_transaction(s); } @@ -359,10 +407,10 @@ static uint64_t smb_ioport_readb(void *opaque, hwaddr addr, unsigned width) val = s->smb_data1; break; case SMBBLKDAT: - if (s->smb_index >= PM_SMBUS_MAX_MSG_SIZE) { - s->smb_index = 0; - } - if (s->smb_auxctl & AUX_BLK) { + if (s->smb_auxctl & AUX_BLK && !s->in_i2c_block_read) { + if (s->smb_index >= PM_SMBUS_MAX_MSG_SIZE) { + s->smb_index = 0; + } val = s->smb_data[s->smb_index++]; if (!s->op_done && s->smb_index == s->smb_data0) { s->op_done = true; |