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Diffstat (limited to 'src/southbridge/amd/cs5535/cs5535_smbus.h')
-rw-r--r--src/southbridge/amd/cs5535/cs5535_smbus.h145
1 files changed, 145 insertions, 0 deletions
diff --git a/src/southbridge/amd/cs5535/cs5535_smbus.h b/src/southbridge/amd/cs5535/cs5535_smbus.h
new file mode 100644
index 0000000000..3a2e4928bf
--- /dev/null
+++ b/src/southbridge/amd/cs5535/cs5535_smbus.h
@@ -0,0 +1,145 @@
+//#include <device/smbus_def.h>
+#define SMBUS_ERROR -1
+#define SMBUS_WAIT_UNTIL_READY_TIMEOUT -2
+#define SMBUS_WAIT_UNTIL_DONE_TIMEOUT -3
+
+enum smb_native_registers {
+ SMB_SDA = 0x00, SMB_STS = 0x01, SMB_CTRL_STS = 0x02,
+ SMB_CTRL1 = 0x03, SMB_ADD = 0x04, SMB_CTRL2 = 0x05,
+ SMB_CTRL3 = 0x06
+};
+
+enum smb_sts_bits {
+ SMB_STS_SLVSTP = (0x01 << 7), SMB_STS_SDAST = (0x01 << 6),
+ SMB_STS_BER = (0x01 << 5), SMB_STS_NEGACK = (0x01 << 4),
+ SMB_STS_STASTR = (0x01 << 3), SMB_STS_NMATCH = (0x01 << 2),
+ SMB_STS_MASTER = (0x01 << 1), SMB_STS_XMIT = (0x01 << 0)
+};
+
+enum smb_ctrl_sts_bits {
+ SMB_CSTS_TGSCL = (0x01 << 5), SMB_CSTS_TSDA = (0x01 << 4),
+ SMB_CSTS_GCMTCH = (0x01 << 3), SMB_CSTS_MATCH = (0x01 << 2),
+ SMB_CSTS_BB = (0x01 << 1), SMB_CSTS_BUSY = (0x01 << 0)
+};
+
+enum smb_ctrl1_bits {
+ SMB_CTRL1_STASTRE = (0x01 << 7), SMB_CTRL1_NMINTE = (0x01 << 6),
+ SMB_CTRL1_GCMEN = (0x01 << 5), SMB_CTRL1_ACK = (0x01 << 4),
+ SMB_CTRL1_RSVD = (0x01 << 3), SMB_CTRL1_INTEN = (0x01 << 2),
+ SMB_CTRL1_STOP = (0x01 << 1), SMB_CTRL1_START = (0x01 << 0)
+};
+
+enum smb_add_bits {
+ SMB_ADD_SAEN = (0x01 << 7)
+};
+
+enum smb_ctrl2_bits {
+ SMB_CTRL2_ENABLE = 0x01,
+};
+
+#define SMBUS_TIMEOUT (100*1000*10)
+#define SMBUS_STATUS_MASK 0xfbff
+
+static inline void smbus_delay(void)
+{
+ outb(0x80, 0x80);
+}
+
+/* generate a smbus start condition */
+static int smbus_start_condition(unsigned smbus_io_base)
+{
+ unsigned char val;
+ unsigned long loops;
+ loops = SMBUS_TIMEOUT;
+
+ /* issue a START condition */
+ val = inb(smbus_io_base + SMB_CTRL1);
+ outb(val | SMB_CTRL1_START, smbus_io_base + SMB_CTRL1);
+
+ /* check for bus conflict */
+ val = inb(smbus_io_base + SMB_STS);
+ if ((val & SMB_STS_BER) != 0)
+ return SMBUS_ERROR;
+
+ /* check for SDA status */
+ do {
+ smbus_delay();
+ val = inw(smbus_io_base + SMB_STS);
+ if ((val & SMB_STS_SDAST) != 0) {
+ break;
+ }
+ } while(--loops);
+ return loops?0:SMBUS_WAIT_UNTIL_READY_TIMEOUT;
+}
+
+static int smbus_send_slave_address(unsigned smbus_io_base, unsigned char device)
+{
+ unsigned char val;
+ unsigned long loops;
+ loops = SMBUS_TIMEOUT;
+
+ /* send the slave address */
+ outb(device, smbus_io_base + SMB_SDA);
+
+ /* check for bus conflict and NACK */
+ val = inb(smbus_io_base + SMB_STS);
+ if ( ((val & SMB_STS_BER) != 0) ||
+ ((val & SMB_STS_NEGACK) != 0))
+ return SMBUS_ERROR;
+
+ /* check for SDA status */
+ do {
+ smbus_delay();
+ val = inw(smbus_io_base + SMB_STS);
+ if ((val & SMB_STS_SDAST) != 0) {
+ break;
+ }
+ } while(--loops);
+ return loops?0:SMBUS_WAIT_UNTIL_READY_TIMEOUT;
+}
+
+static int smbus_send_command(unsigned smbus_io_base, unsigned char command)
+{
+ unsigned char val;
+ unsigned long loops;
+ loops = SMBUS_TIMEOUT;
+
+ /* send the command */
+ outb(command, smbus_io_base + SMB_SDA);
+
+ /* check for bus conflict and NACK */
+ val = inb(smbus_io_base + SMB_STS);
+ if ( ((val & SMB_STS_BER) != 0) ||
+ ((val & SMB_STS_NEGACK) != 0))
+ return SMBUS_ERROR;
+
+ /* check for SDA status */
+ do {
+ smbus_delay();
+ val = inw(smbus_io_base + SMB_STS);
+ if ((val & SMB_STS_SDAST) != 0) {
+ break;
+ }
+ } while(--loops);
+ return loops?0:SMBUS_WAIT_UNTIL_READY_TIMEOUT;
+}
+
+static int do_smbus_read_byte(unsigned smbus_io_base, unsigned char device, unsigned char address)
+{
+ unsigned char val;
+
+ smbus_start_condition(smbus_io_base);
+
+ smbus_send_slave_address(smbus_io_base, device);
+
+ smbus_send_command(smbus_io_base, address);
+
+ smbus_start_condition(smbus_io_base);
+
+ smbus_send_slave_address(smbus_io_base, device | 0x01);
+
+ val = inb(smbus_io_base + SMB_CTRL1);
+ outb(val | SMB_CTRL1_ACK, smbus_io_base + SMB_CTRL1);
+
+ return inb(smbus_io_base + SMB_SDA);
+}