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-rw-r--r--hw/i2c/pm_smbus.c86
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;