On Fri, 2007-12-14 at 00:03 +0100, Joakim Tjernlund wrote:
-----Original Message----- From: Jerry Van Baren [mailto:gerald.vanbaren@ge.com] Sent: den 13 december 2007 19:49 To: Wolfgang Denk Cc: joakim.tjernlund@transmode.se; u-boot-users@lists.sourceforge.net Subject: Re: [U-Boot-Users] Can U-boot Autodetect arch/ppcversusarch/powerpc from info in the uImage?
Wolfgang Denk wrote:
In message
1197205927.937.51.camel@gentoo-jocke.transmode.se you wrote:
Made a new patch with Jerrys comments addressed. Also renamed DEFAULT_OF_TREE to CFG_OF_TREE. OK?
I still object against this modification.
+#ifdef CFG_OF_TREE
- char *of_flat_tree = CFG_OF_TREE;
+#else char *of_flat_tree = NULL; +#endif ulong of_data = 0; #endif
I hereby NAK this patch for 3 reasons:
The patch does not solve a problem. Instead of hardwiring the address, you can just pass it as argument to the bootm command which seems more straightforward to me
The patch causes confusion. Documented behaviour is that "bootm" with one or two arguments (kernel address, or kernel plus ramdisk addresses) will boot a non-OF enabled kernel. With this patch, "bootm" will behave different on systems where the
CFG_OF_TREE has
been selected - which is usually not known to and cannot be checked by the end user, thus causing confusion.
- With the patch applied and CFG_OF_TREE defined, there is
no way to
boot a non-OF kernel, thus breaking backward compatibility.
Best regards,
Wolfgang Denk
FWIIW, #2 and #3 are serious problems that I had not considered when I supported Jocke's proposed patch. Sorry, Jocke, but I have to side with Wolfgang in light of those arguments.
Right and I havn't been able to come up with a solution to that either. So I am looking at passing a $dtb to bootm.
I noticed that I could define dtb i HUSH only by dtb=0x12345678 Is it possible to do that from within board code too?
If so I don't have to worry about deleting $dtb when downgrading, because it will never be saved in the env.
Jocke
This is what I came up with to make $dtb a hush variable that don't end up in the environment:
#define FLAG_PARSE_SEMICOLON (1 << 1) #define FLAG_EXIT_FROM_LOOP 1 int misc_init_r (void) { char *bootstr, dtb_str[30], workstr[256];
u_boot_hush_start(); sprintf(dtb_str, "dtb=0x%lx", (ulong)dt_blob_start); /* Set $dtb in local HUSH env.to my OF tree */ if (parse_string_outer(dtb_str, FLAG_PARSE_SEMICOLON | FLAG_EXIT_FROM_LOOP) != 0) { /* Add " - $dtb" to $bootcmd if it is missing */ bootstr = getenv("bootcmd"); if (bootstr && !strstr(bootstr, "- $dtb")) { strcpy(workstr, bootstr); strcat(workstr, " - $dtb"); setenv("bootcmd", workstr); } } return 0; }
It is fairly ugly, but it works. Comments?
BTW, whats syntax is preferred in HUSH for variables: $var or ${var}?
Jocke