Hi Wolfgang,
On Wed, Mar 28, 2012 at 11:30 PM, Wolfgang Denk wd@denx.de wrote:
Dear Simon Glass,
In message 1332965305-21151-1-git-send-email-sjg@chromium.org you wrote:
CONFIG_OF_CONTROL requires a valid device tree. However, we cannot call panic() before the console is set up since the message does not appear, and we get a silent failure.
...
+int fdtdec_prepare_fdt(void);
+/**
- Checks that we have a valid fdt available to control U-Boot.
- However, if not then for the moment nothing is done, since this function
- is called too early to panic().
- @returns 0
If the function always returns 0, then it makes no sense to return any value at all. Please make it void, then.
fdtdec_check_fdt() is used in the ARM init sequence, so I need to follow that signature and return a value. In fact I must return 0 or the board will hang.
+int fdtdec_check_fdt(void) +{
- /*
- * We must have an FDT, but we cannot panic() yet since the console
- * is not ready. So for now, just assert(). Boards which need an early
- * FDT (prior to console ready) will need to make their own
- * arrangements and do their own checks.
- */
- assert(!fdtdec_prepare_fdt());
- return 0;
+}
Ditto - make that "void fdtdec_check_fdt(void)".
+int fdtdec_prepare_fdt(void)
...
return 0; }
Ditto - make that "void fdtdec_prepare_fdt(void)".
This fdtdec_prepare_fdt() is intended to provide a way to find out if there is a valid fdt. The 'return 0' that you have shown is only if it succeeds - it does actually return -1 on failure. I want a function which just checks this, and returns the result (rather than dying if it fails, which the behaviour that in principle I would like in the init sequence).
I have to admit that I do not understand how this patch will help you anything. You write "we cannot panic()", but "just assert()".
If the assertion fails, it will call __assert_fail() - which in turn will just call panic(). So you are out of the frying pan into the fire.
Yes, but only if DEBUG is turned on in fdtdec. Otherwise we just continue and panic later when we can report the error.
Regards, Simon
Best regards,
Wolfgang Denk
-- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de Life. Don't talk to me about life. - Marvin the Paranoid Android