Hi, Mike and Wolfgang,
2011/9/1 Mike Frysinger vapier@gentoo.org:
On Thursday, September 01, 2011 01:52:46 Macpaul Lin wrote:
[... skipped and will discuss these later]
+void board_init_f(ulong bootflag) +{ ...
- /* Pointer is writable since we allocated a register for it */
- gd = (gd_t *) ((CONFIG_SYS_INIT_SP_ADDR) & ~0x07);
- /* compiler optimization barrier needed for GCC >= 3.4 */
- __asm__ __volatile__("" : : : "memory");
- memset((void *)gd, 0, sizeof(gd_t));
err, is that barrier really needed ? sounds like a bug in your compiler.
I'm not sure if this is really a bug which has been fixed or this is still a common problem. I've found there are architectures x86, mips, m68k, nios2, powerpc have this code to do optimization barrier. I'll try to verify this with our toolchain department, but I think this might be a common problem. Could someone give a comment on this?
as for the memset, it should be: memset((void *)gd, 0, GENERATED_GBL_DATA_SIZE);
It's the similar case. Since we have generated header file for global data, this code might be good. However, there are other architecture remain the same code which do memset with sizeof(gd_t). Included m68k, sparc, arm, avr32 and powerpc. Do I miss something of the discussion before in the mailing list? Should these also be a clean up for other architectures, too?
- addr_sp -= sizeof(bd_t);
sizeof(bd_t) -> GENERATED_BD_INFO_SIZE
this shows up multiple times
also, did i miss something, or do you not zero out your board info ?
- addr_sp -= sizeof(gd_t);
sizeof(gd_t) -> GENERATED_GBL_DATA_SIZE
this shows up multiple times -mike
No, I didn't zero out the board info just like the implementation of other architecture. Dose this lead a problem?