README: document CONFIG_ENV_IS_IN_SPI_FLASH
The option can be used to save the environment in spi flash.
Implementation code is already exist in command/env_sf.c. But
the documentation is missing.
This patch add the details for this option to the README file.
Signed-off-by: Josh Wu <josh.wu@atmel.com>
Reviewed-by: Jagannadha Sutradharudu Teki <jaganna@xilinx.com>
diff --git a/README b/README
index 0c98545..2bc0d35 100644
--- a/README
+++ b/README
@@ -4069,6 +4069,43 @@
environment area within the total memory of your DataFlash placed
at the specified address.
+- CONFIG_ENV_IS_IN_SPI_FLASH:
+
+ Define this if you have a SPI Flash memory device which you
+ want to use for the environment.
+
+ - CONFIG_ENV_OFFSET:
+ - CONFIG_ENV_SIZE:
+
+ These two #defines specify the offset and size of the
+ environment area within the SPI Flash. CONFIG_ENV_OFFSET must be
+ aligned to an erase sector boundary.
+
+ - CONFIG_ENV_SECT_SIZE:
+
+ Define the SPI flash's sector size.
+
+ - CONFIG_ENV_OFFSET_REDUND (optional):
+
+ This setting describes a second storage area of CONFIG_ENV_SIZE
+ size used to hold a redundant copy of the environment data, so
+ that there is a valid backup copy in case there is a power failure
+ during a "saveenv" operation. CONFIG_ENV_OFFSET_RENDUND must be
+ aligned to an erase sector boundary.
+
+ - CONFIG_ENV_SPI_BUS (optional):
+ - CONFIG_ENV_SPI_CS (optional):
+
+ Define the SPI bus and chip select. If not defined they will be 0.
+
+ - CONFIG_ENV_SPI_MAX_HZ (optional):
+
+ Define the SPI max work clock. If not defined then use 1MHz.
+
+ - CONFIG_ENV_SPI_MODE (optional):
+
+ Define the SPI work mode. If not defined then use SPI_MODE_3.
+
- CONFIG_ENV_IS_IN_REMOTE:
Define this if you have a remote memory space which you