S5PC100: Memory SubSystem Header file, register description(SROMC).

[karo-tx-uboot.git] / README

diff --git a/README b/README
index 22e35c39bc4deaa553aa3eb226caef51c7ab2da8..263bb05076b7025d0ae00a1450d46a4f028301a4 100644 (file)
--- a/README
+++ b/README
@@ -2447,6 +2447,19 @@ to save the current settings.
        - CONFIG_SYS_EEPROM_SIZE:
          The size in bytes of the EEPROM device.
 
+       - CONFIG_ENV_EEPROM_IS_ON_I2C
+         define this, if you have I2C and SPI activated, and your
+         EEPROM, which holds the environment, is on the I2C bus.
+
+       - CONFIG_I2C_ENV_EEPROM_BUS
+         if you have an Environment on an EEPROM reached over
+         I2C muxes, you can define here, how to reach this
+         EEPROM. For example:
+
+         #define CONFIG_I2C_ENV_EEPROM_BUS       "pca9547:70:d\0"
+
+         EEPROM which holds the environment, is reached over
+         a pca9547 i2c mux with address 0x70, channel 3.
 
 - CONFIG_ENV_IS_IN_DATAFLASH:
 
@@ -3909,7 +3922,9 @@ For PowerPC, the following registers have specific use:
        R30:    GOT pointer
        R31:    frame pointer
 
-       (U-Boot also uses R14 as internal GOT pointer.)
+       (U-Boot also uses R12 as internal GOT pointer. r12
+       is a volatile register so r12 needs to be reset when
+       going back and forth between asm and C)
 
     ==> U-Boot will use R2 to hold a pointer to the global data