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-rw-r--r--README23
1 files changed, 14 insertions, 9 deletions
diff --git a/README b/README
index 81692c0a4..a9c98f218 100644
--- a/README
+++ b/README
@@ -143,9 +143,9 @@ Directory Hierarchy:
/cpu CPU specific files
/arm720t Files specific to ARM 720 CPUs
/arm920t Files specific to ARM 920 CPUs
- /at91rm9200 Files specific to Atmel AT91RM9200 CPU
- /imx Files specific to Freescale MC9328 i.MX CPUs
- /s3c24x0 Files specific to Samsung S3C24X0 CPUs
+ /at91rm9200 Files specific to Atmel AT91RM9200 CPU
+ /imx Files specific to Freescale MC9328 i.MX CPUs
+ /s3c24x0 Files specific to Samsung S3C24X0 CPUs
/arm925t Files specific to ARM 925 CPUs
/arm926ejs Files specific to ARM 926 CPUs
/arm1136 Files specific to ARM 1136 CPUs
@@ -177,9 +177,6 @@ Directory Hierarchy:
/mips Files generic to MIPS architecture
/cpu CPU specific files
/lib Architecture specific library files
- /nios Files generic to Altera NIOS architecture
- /cpu CPU specific files
- /lib Architecture specific library files
/nios2 Files generic to Altera NIOS2 architecture
/cpu CPU specific files
/lib Architecture specific library files
@@ -2507,7 +2504,7 @@ to save the current settings.
I2C muxes, you can define here, how to reach this
EEPROM. For example:
- #define CONFIG_I2C_ENV_EEPROM_BUS "pca9547:70:d\0"
+ #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.
@@ -3337,8 +3334,8 @@ details; basically, the header defines the following image properties:
Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
INTEGRITY).
* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
- IA64, MIPS, NIOS, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
- Currently supported: ARM, AVR32, Intel x86, MIPS, NIOS, PowerPC).
+ IA64, MIPS, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
+ Currently supported: ARM, AVR32, Intel x86, MIPS, Nios II, PowerPC).
* Compression Type (uncompressed, gzip, bzip2)
* Load Address
* Entry Point
@@ -4023,6 +4020,14 @@ On ARM, the following registers are used:
==> U-Boot will use R8 to hold a pointer to the global data
+On Nios II, the ABI is documented here:
+ http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
+
+ ==> U-Boot will use gp to hold a pointer to the global data
+
+ Note: on Nios II, we give "-G0" option to gcc and don't use gp
+ to access small data sections, so gp is free.
+
NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
or current versions of GCC may "optimize" the code too much.