+/* define the I2C bus number for RTC and DTT if not already done */
+#if !defined(CONFIG_SYS_RTC_BUS_NUM)
+#define CONFIG_SYS_RTC_BUS_NUM 0
+#endif
+#if !defined(CONFIG_SYS_DTT_BUS_NUM)
+#define CONFIG_SYS_DTT_BUS_NUM 0
+#endif
+#if !defined(CONFIG_SYS_SPD_BUS_NUM)
+#define CONFIG_SYS_SPD_BUS_NUM 0
+#endif
+
+#ifndef I2C_SOFT_DECLARATIONS
+# if defined(CONFIG_MPC8260)
+# define I2C_SOFT_DECLARATIONS volatile ioport_t *iop = ioport_addr((immap_t *)CONFIG_SYS_IMMR, I2C_PORT);
+# elif defined(CONFIG_8xx)
+# define I2C_SOFT_DECLARATIONS volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
+# else
+# define I2C_SOFT_DECLARATIONS
+# endif
+#endif
+
+#ifdef CONFIG_8xx
+/* Set default value for the I2C bus speed on 8xx. In the
+ * future, we'll define these in all 8xx board config files.
+ */
+#ifndef CONFIG_SYS_I2C_SPEED
+#define CONFIG_SYS_I2C_SPEED 50000
+#endif
+#endif
+
+/*
+ * Many boards/controllers/drivers don't support an I2C slave interface so
+ * provide a default slave address for them for use in common code. A real
+ * value for CONFIG_SYS_I2C_SLAVE should be defined for any board which does
+ * support a slave interface.
+ */
+#ifndef CONFIG_SYS_I2C_SLAVE
+#define CONFIG_SYS_I2C_SLAVE 0xfe
+#endif
+