/mips32 Files specific to MIPS32 CPUs
/xburst Files specific to Ingenic XBurst CPUs
/lib Architecture specific library files
+ /nds32 Files generic to NDS32 architecture
+ /cpu CPU specific files
+ /n1213 Files specific to Andes Technology N1213 CPUs
+ /lib Architecture specific library files
/nios2 Files generic to Altera NIOS2 architecture
/cpu CPU specific files
/lib Architecture specific library files
parameters are extracted from datasheet and hard-coded into
header files or board specific files.
+- CONFIG_FSL_DDR_INTERACTIVE
+ Enable interactive DDR debugging. See doc/README.fsl-ddr.
+
- CONFIG_SYS_83XX_DDR_USES_CS0
Only for 83xx systems. If specified, then DDR should
be configured using CS0 and CS1 instead of CS2 and CS3.
globally (CONFIG_CMD_MEM).
- CONFIG_SKIP_LOWLEVEL_INIT
- [ARM, MIPS only] If this variable is defined, then certain
+ [ARM, NDS32, MIPS only] If this variable is defined, then certain
low level initializations (like setting up the memory
controller) are omitted and/or U-Boot does not
relocate itself into RAM.
Ethernet is encapsulated/received over 802.1q
VLAN tagged frames.
+The following image location variables contain the location of images
+used in booting. The "Image" column gives the role of the image and is
+not an environment variable name. The other columns are environment
+variable names. "File Name" gives the name of the file on a TFTP
+server, "RAM Address" gives the location in RAM the image will be
+loaded to, and "Flash Location" gives the image's address in NOR
+flash or offset in NAND flash.
+
+*Note* - these variables don't have to be defined for all boards, some
+boards currenlty use other variables for these purposes, and some
+boards use these variables for other purposes.
+
+Image File Name RAM Address Flash Location
+----- --------- ----------- --------------
+u-boot u-boot u-boot_addr_r u-boot_addr
+Linux kernel bootfile kernel_addr_r kernel_addr
+device tree blob fdtfile fdt_addr_r fdt_addr
+ramdisk ramdiskfile ramdisk_addr_r ramdisk_addr
+
The following environment variables may be used and automatically
updated by the network boot commands ("bootp" and "rarpboot"),
depending the information provided by your boot server:
Currently supported: Linux, NetBSD, VxWorks, QNX, RTEMS, LynxOS,
INTEGRITY).
* Target CPU Architecture (Provisions for Alpha, ARM, AVR32, Intel x86,
- IA64, MIPS, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
- Currently supported: ARM, AVR32, Intel x86, MIPS, Nios II, PowerPC).
+ IA64, MIPS, NDS32, Nios II, PowerPC, IBM S390, SuperH, Sparc, Sparc 64 Bit;
+ Currently supported: ARM, AVR32, Intel x86, MIPS, NDS32, Nios II, PowerPC).
* Compression Type (uncompressed, gzip, bzip2)
* Load Address
* Entry Point
Note: on Nios II, we give "-G0" option to gcc and don't use gp
to access small data sections, so gp is free.
+On NDS32, the following registers are used:
+
+ R0-R1: argument/return
+ R2-R5: argument
+ R15: temporary register for assembler
+ R16: trampoline register
+ R28: frame pointer (FP)
+ R29: global pointer (GP)
+ R30: link register (LP)
+ R31: stack pointer (SP)
+ PC: program counter (PC)
+
+ ==> U-Boot will use R10 to hold a pointer to the global data
+
NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
or current versions of GCC may "optimize" the code too much.