malloc: sbrk() should return MORECORE_FAILURE instead of NULL on failure

[karo-tx-uboot.git] / README

diff --git a/README b/README
index 22e35c39bc4deaa553aa3eb226caef51c7ab2da8..bb13bc62a37e3892ade156979fa9f2f69f92dc3b 100644 (file)
--- a/README
+++ b/README
@@ -822,6 +822,16 @@ The following options need to be configured:
 
 - NETWORK Support (other):
 
+               CONFIG_DRIVER_AT91EMAC
+               Support for AT91RM9200 EMAC.
+
+                       CONFIG_RMII
+                       Define this to use reduced MII inteface
+
+                       CONFIG_DRIVER_AT91EMAC_QUIET
+                       If this defined, the driver is quiet.
+                       The driver doen't show link status messages.
+
                CONFIG_DRIVER_LAN91C96
                Support for SMSC's LAN91C96 chips.
 
@@ -1123,6 +1133,12 @@ The following options need to be configured:
                images, gzipped BMP images can be displayed via the
                splashscreen support or the bmp command.
 
+- Run length encoded BMP image (RLE8) support: CONFIG_VIDEO_BMP_RLE8
+
+               If this option is set, 8-bit RLE compressed BMP images
+               can be displayed via the splashscreen support or the
+               bmp command.
+
 - Compression support:
                CONFIG_BZIP2
 
@@ -2447,6 +2463,19 @@ 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:
 
@@ -2982,7 +3011,9 @@ environment. As long as you don't save the environment you are
 working with an in-memory copy. In case the Flash area containing the
 environment is erased by accident, a default environment is provided.
 
-Some configuration options can be set using Environment Variables:
+Some configuration options can be set using Environment Variables.
+
+List of environment variables (most likely not complete):
 
   baudrate     - see CONFIG_BAUDRATE
 
@@ -3094,7 +3125,7 @@ Some configuration options can be set using Environment Variables:
                  available network interfaces.
                  It just stays at the currently selected interface.
 
-   netretry    - When set to "no" each network operation will
+  netretry     - When set to "no" each network operation will
                  either succeed or fail without retrying.
                  When set to "once" the network operation will
                  fail when all the available network interfaces
@@ -3110,7 +3141,18 @@ Some configuration options can be set using Environment Variables:
   tftpdstport  - If this is set, the value is used for TFTP's UDP
                  destination port instead of the Well Know Port 69.
 
-   vlan                - When set to a value < 4095 the traffic over
+  tftpblocksize - Block size to use for TFTP transfers; if not set,
+                 we use the TFTP server's default block size
+
+  tftptimeout  - Retransmission timeout for TFTP packets (in milli-
+                 seconds, minimum value is 1000 = 1 second). Defines
+                 when a packet is considered to be lost so it has to
+                 be retransmitted. The default is 5000 = 5 seconds.
+                 Lowering this value may make downloads succeed
+                 faster in networks with high packet loss rates or
+                 with unreliable TFTP servers.
+
+  vlan         - When set to a value < 4095 the traffic over
                  Ethernet is encapsulated/received over 802.1q
                  VLAN tagged frames.
 
@@ -3909,7 +3951,9 @@ 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