summaryrefslogtreecommitdiff
path: root/src/southbridge
diff options
context:
space:
mode:
Diffstat (limited to 'src/southbridge')
-rw-r--r--src/southbridge/intel/common/smbus.c177
1 files changed, 84 insertions, 93 deletions
diff --git a/src/southbridge/intel/common/smbus.c b/src/southbridge/intel/common/smbus.c
index de4ff91cfd..b2a78c9fc1 100644
--- a/src/southbridge/intel/common/smbus.c
+++ b/src/southbridge/intel/common/smbus.c
@@ -53,6 +53,10 @@
#define SMBHSTSTS_INTR (1 << 1)
#define SMBHSTSTS_HOST_BUSY (1 << 0)
+/* For SMBXMITADD register. */
+#define XMIT_WRITE(dev) (((dev) << 1) | 0)
+#define XMIT_READ(dev) (((dev) << 1) | 1)
+
#define SMBUS_TIMEOUT (10 * 1000 * 100)
#define SMBUS_BLOCK_MAXLEN 32
@@ -61,31 +65,40 @@ static void smbus_delay(void)
inb(0x80);
}
-static int smbus_wait_until_ready(u16 smbus_base)
+static int recover_master(int smbus_base, int ret)
{
- unsigned int loops = SMBUS_TIMEOUT;
- unsigned char byte;
- do {
- smbus_delay();
- if (--loops == 0)
- break;
- byte = inb(smbus_base + SMBHSTSTAT);
- } while (byte & SMBHSTSTS_HOST_BUSY);
- return loops ? 0 : -1;
+ /* TODO: Depending of the failure, drive KILL transaction
+ * or force soft reset on SMBus master controller.
+ */
+ printk(BIOS_ERR, "SMBus: Fatal master timeout (%d)\n", ret);
+ return ret;
}
-static int smbus_wait_until_done(u16 smbus_base)
+static int setup_command(unsigned int smbus_base, u8 ctrl, u8 xmitadd)
{
unsigned int loops = SMBUS_TIMEOUT;
- unsigned char byte;
+ u8 host_busy;
+
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;
+ host_busy = inb(smbus_base + SMBHSTSTAT) & SMBHSTSTS_HOST_BUSY;
+ } while (--loops && host_busy);
+
+ if (loops == 0)
+ return recover_master(smbus_base,
+ SMBUS_WAIT_UNTIL_READY_TIMEOUT);
+
+ /* Clear any lingering errors, so the transaction will run. */
+ outb(inb(smbus_base + SMBHSTSTAT), smbus_base + SMBHSTSTAT);
+
+ /* Set up transaction */
+ /* Disable interrupts */
+ outb(ctrl, (smbus_base + SMBHSTCTL));
+
+ /* Set the device I'm talking to. */
+ outb(xmitadd, smbus_base + SMBXMITADD);
+
+ return 0;
}
static int smbus_wait_until_active(u16 smbus_base)
@@ -103,27 +116,34 @@ static int smbus_wait_until_active(u16 smbus_base)
return loops ? 0 : -1;
}
+static int smbus_wait_until_done(u16 smbus_base)
+{
+ unsigned int loops = SMBUS_TIMEOUT;
+ unsigned char byte;
+ 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;
+}
+
int do_smbus_read_byte(unsigned int smbus_base, u8 device,
unsigned int address)
{
+ int ret;
unsigned char status;
unsigned char byte;
- if (smbus_wait_until_ready(smbus_base) < 0)
- return SMBUS_WAIT_UNTIL_READY_TIMEOUT;
- /* Set up transaction */
- /* Disable interrupts */
- outb(inb(smbus_base + SMBHSTCTL) & ~SMBHSTCNT_INTREN,
- smbus_base + SMBHSTCTL);
- /* Set the device I'm talking to */
- outb(((device & 0x7f) << 1) | 1, smbus_base + SMBXMITADD);
+ /* Set up for a byte data read. */
+ ret = setup_command(smbus_base, I801_BYTE_DATA, XMIT_READ(device));
+ if (ret < 0)
+ return ret;
+
/* Set the command/address... */
- outb(address & 0xff, smbus_base + SMBHSTCMD);
- /* Set up for a byte data read */
- outb((inb(smbus_base + SMBHSTCTL) & 0xe3) | I801_BYTE_DATA,
- (smbus_base + SMBHSTCTL));
- /* Clear any lingering errors, so the transaction will run */
- outb(inb(smbus_base + SMBHSTSTAT), smbus_base + SMBHSTSTAT);
+ outb(address, smbus_base + SMBHSTCMD);
/* Clear the data byte... */
outb(0, smbus_base + SMBHSTDAT0);
@@ -156,25 +176,17 @@ int do_smbus_write_byte(unsigned int smbus_base, u8 device,
unsigned int address, unsigned int data)
{
unsigned char status;
+ int ret;
- if (smbus_wait_until_ready(smbus_base) < 0)
- return SMBUS_WAIT_UNTIL_READY_TIMEOUT;
+ /* Set up for a byte data write. */
+ ret = setup_command(smbus_base, I801_BYTE_DATA, XMIT_WRITE(device));
+ if (ret < 0)
+ return ret;
- /* Set up transaction */
- /* Disable interrupts */
- outb(inb(smbus_base + SMBHSTCTL) & ~SMBHSTCNT_INTREN,
- smbus_base + SMBHSTCTL);
- /* Set the device I'm talking to */
- outb(((device & 0x7f) << 1) & ~0x01, smbus_base + SMBXMITADD);
/* Set the command/address... */
- outb(address & 0xff, smbus_base + SMBHSTCMD);
- /* Set up for a byte data read */
- outb((inb(smbus_base + SMBHSTCTL) & 0xe3) | I801_BYTE_DATA,
- (smbus_base + SMBHSTCTL));
- /* Clear any lingering errors, so the transaction will run */
- outb(inb(smbus_base + SMBHSTSTAT), smbus_base + SMBHSTSTAT);
+ outb(address, smbus_base + SMBHSTCMD);
- /* Clear the data byte... */
+ /* Set the data byte... */
outb(data, smbus_base + SMBHSTDAT0);
/* Start the command */
@@ -205,27 +217,19 @@ int do_smbus_block_read(unsigned int smbus_base, u8 device, u8 cmd,
unsigned int max_bytes, u8 *buf)
{
u8 status;
- int slave_bytes;
+ int ret, 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(SMBUS_BLOCK_MAXLEN, max_bytes);
- /* Set up transaction */
- /* Disable interrupts */
- outb(inb(smbus_base + SMBHSTCTL) & ~SMBHSTCNT_INTREN,
- smbus_base + SMBHSTCTL);
- /* Set the device I'm talking to */
- outb(((device & 0x7f) << 1) | 1, smbus_base + SMBXMITADD);
+ /* Set up for a block data read. */
+ ret = setup_command(smbus_base, I801_BLOCK_DATA, XMIT_READ(device));
+ if (ret < 0)
+ return ret;
+
/* Set the command/address... */
- outb(cmd & 0xff, smbus_base + SMBHSTCMD);
- /* Set up for a block data read */
- 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);
+ outb(cmd, smbus_base + SMBHSTCMD);
/* Reset number of bytes to transfer so we notice later it
* was really updated with the transaction. */
@@ -279,30 +283,21 @@ int do_smbus_block_write(unsigned int smbus_base, u8 device, u8 cmd,
const unsigned int bytes, const u8 *buf)
{
u8 status;
- int bytes_sent = 0;
+ int ret, bytes_sent = 0;
unsigned int loops = SMBUS_TIMEOUT;
if (bytes > SMBUS_BLOCK_MAXLEN)
return SMBUS_ERROR;
- if (smbus_wait_until_ready(smbus_base) < 0)
- return SMBUS_WAIT_UNTIL_READY_TIMEOUT;
+ /* Set up for a block data write. */
+ ret = setup_command(smbus_base, I801_BLOCK_DATA, XMIT_WRITE(device));
+ if (ret < 0)
+ return ret;
- /* Set up transaction */
- /* Disable interrupts */
- outb(inb(smbus_base + SMBHSTCTL) & ~SMBHSTCNT_INTREN,
- smbus_base + SMBHSTCTL);
- /* Set the device I'm talking to */
- outb(((device & 0x7f) << 1) & ~0x01, smbus_base + SMBXMITADD);
/* Set the command/address... */
- outb(cmd & 0xff, smbus_base + SMBHSTCMD);
- /* Set up for a block data write */
- 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);
+ outb(cmd, smbus_base + SMBHSTCMD);
- /* set number of bytes to transfer */
+ /* Set number of bytes to transfer. */
outb(bytes, smbus_base + SMBHSTDAT0);
/* Send first byte from buffer, bytes_sent increments after
@@ -354,27 +349,23 @@ int do_i2c_block_read(unsigned int smbus_base, u8 device,
unsigned int offset, const unsigned int bytes, u8 *buf)
{
u8 status;
- int bytes_read = 0;
+ int ret, bytes_read = 0;
unsigned int loops = SMBUS_TIMEOUT;
- if (smbus_wait_until_ready(smbus_base) < 0)
- return SMBUS_WAIT_UNTIL_READY_TIMEOUT;
- /* Set upp transaction */
- /* Disable interrupts */
- outb(inb(smbus_base + SMBHSTCTL) & SMBHSTCNT_INTREN,
- smbus_base + SMBHSTCTL);
- /* Set the device I'm talking to */
- outb((device & 0x7f) << 1, smbus_base + SMBXMITADD);
+ /* Set up for a i2c block data read.
+ *
+ * FIXME: Address parameter changes to XMIT_READ(device) with
+ * some revision of PCH. Presumably hardware revisions that
+ * do not have i2c block write support internally set LSB.
+ */
+ ret = setup_command(smbus_base, I801_I2C_BLOCK_DATA,
+ XMIT_WRITE(device));
+ if (ret < 0)
+ return ret;
/* device offset */
outb(offset, smbus_base + SMBHSTDAT1);
- /* Set up for a i2c block data read */
- outb((inb(smbus_base + SMBHSTCTL) & 0xc3) | I801_I2C_BLOCK_DATA,
- (smbus_base + SMBHSTCTL));
-
- /* Clear any lingering errors, so the transaction will run */
- outb(inb(smbus_base + SMBHSTSTAT), smbus_base + SMBHSTSTAT);
/* Start the command */
outb((inb(smbus_base + SMBHSTCTL) | SMBHSTCNT_START),
smbus_base + SMBHSTCTL);
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-29 17:43:54 +0000