mpc8313erdb: Document NAND boot.

Previously, the documentation claimed that NAND boot is not supported.
This is no longer true.
Signed-off-by: NScott Wood <scottwood@freescale.com>

doc/README.mpc8313erdb

@@ -15,6 +15,18 @@ Freescale MPC8313ERDB Board
 	  4321		  4321
 	(where the '*' indicates the position of the tab of the switch.)
 
+	To boot the image at the beginning of NAND flash, use these
+	DIP switch settings for S3 S4:
+
+	+------+	+------+
+	| *    |	|  *** |
+	|  *** |	| *    |
+	+------+ ON	+------+ ON
+	  4321		  4321
+	(where the '*' indicates the position of the tab of the switch.)
+
+	When booting from NAND, use u-boot-nand.bin, not u-boot.bin.
+
 2.	Memory Map
 	The memory map looks like this:
 
@@ -29,6 +41,9 @@ Freescale MPC8313ERDB Board
 					LED Control (CS3)
 	0xfe00_0000	0xfe7f_ffff	NOR FLASH (CS0)	 8M
 
+	When booting from NAND, NAND flash is CS0 and NOR flash
+	is CS1.
+
 3.	Definitions
 
 3.1	Explanation of NEW definitions in:
@@ -45,15 +60,20 @@ Freescale MPC8313ERDB Board
 
 	export CROSS_COMPILE=your-cross-compiler-prefix-
 	make distclean
-	make MPC8313ERDB_33_config
-	(or make MPC8313ERDB_66_config, depending on the speed of
-	 the oscillator on your board)
+	make MPC8313ERDB_XXX_config
+	(where XXX is:
+	   33 - 33 MHz oscillator, boot from NOR flash
+	   66 - 66 MHz oscillator, boot from NOR flash
+	   NAND_33 - 33 MHz oscillator, boot from NAND flash
+	   NAND_66 - 66 MHz oscillator, boot from NAND flash)
 	make
 
 5.	Downloading and Flashing Images
 
 5.1	Reflash U-boot Image using U-boot
 
+	NOR flash:
+
 	=>run tftpflash
 
 	You may want to try
@@ -63,6 +83,15 @@ Freescale MPC8313ERDB Board
 	have an alternate means of programming the flash available
 	if the new u-boot doesn't boot.
 
+	NAND flash:
+
+	=>tftpboot $loadaddr <filename>
+	=>nand erase 0 0x80000
+	=>nand write $loadaddr 0 0x80000
+
+	...where 0x80000 is the filesize rounded up to
+	the next 0x20000 increment.
+
 5.2	Downloading and Booting Linux Kernel
 
 	Ensure that all networking-related environment variables are set
@@ -79,5 +108,4 @@ Freescale MPC8313ERDB Board
 
 6	Notes
 
-	Booting from NAND flash is not yet supported.
 	The console baudrate for MPC8313ERDB is 115200bps.