thus the compiler cannot perform type checks on these assignments.
2. The pointer to the jump table is passed to the application in a
- machine-dependent way. PowerPC, ARM, MIPS and Blackfin architectures
- use a dedicated register to hold the pointer to the 'global_data'
- structure: r2 on PowerPC, r8 on ARM, k0 on MIPS, and P5 on Blackfin.
- The x86 architecture does not use such a register; instead, the
- pointer to the 'global_data' structure is passed as 'argv[-1]'
- pointer.
+ machine-dependent way. PowerPC, ARM, MIPS, Blackfin and Nios II
+ architectures use a dedicated register to hold the pointer to the
+ 'global_data' structure: r2 on PowerPC, r9 on ARM, k0 on MIPS,
+ P3 on Blackfin and gp on Nios II. The x86 architecture does not
+ use such a register; instead, the pointer to the 'global_data'
+ structure is passed as 'argv[-1]' pointer.
The application can access the 'global_data' structure in the same
way as U-Boot does:
that returns the ABI version of the running U-Boot. I.e., a
typical application startup may look like this:
- int my_app (int argc, char *argv[])
+ int my_app (int argc, char * const argv[])
{
app_startup (argv);
if (get_version () != XF_VERSION)
ARM 0x0c100000 0x0c100000
MIPS 0x80200000 0x80200000
Blackfin 0x00001000 0x00001000
+ NDS32 0x00300000 0x00300000
+ Nios II 0x02000000 0x02000000
For example, the "hello world" application may be loaded and
executed on a PowerPC board with the following commands: