Messages in this thread Patch in this message | | | Date | Tue, 16 Sep 2003 01:30:08 +0200 | From | "Mario 'BitKoenig' Holbe" <> | Subject | Re: 2.4.22: ide-scsi interfers with APM |
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On Sun, Sep 14, 2003 at 05:13:52PM +0200, Mario 'BitKoenig' Holbe wrote: > ide-scsi works fine, if CONFIG_APM=m is defined: > it does not, if CONFIG_APM is undefined: > > I have no explanation for this and no idea how to debug it > down. Hopefully someone else is able to explain it to me.
Okay, now I'm able to explain it myself. It's a timing issue.
After this it works well even with CONFIG_APM is undefined:
--- kernel-source-2.4.22.old/include/linux/ide.h 2003-09-15 09:49:34.000000000 +0200 +++ kernel-source-2.4.22/include/linux/ide.h 2003-09-15 21:22:57.000000000 +0200 @@ -271,7 +271,7 @@ #if defined(CONFIG_APM) || defined(CONFIG_APM_MODULE) #define WAIT_READY (5*HZ) /* 5sec - some laptops are very slow */ #else -#define WAIT_READY (3*HZ/100) /* 30msec - should be instantaneous */ +#define WAIT_READY (4*HZ/100) /* 40msec - should be instantaneous */ #endif /* CONFIG_APM || CONFIG_APM_MODULE */ #define WAIT_PIDENTIFY (10*HZ) /* 10sec - should be less than 3ms (?), if all ATAPI CD is closed at boot */ #define WAIT_WORSTCASE (30*HZ) /* 30sec - worst case when spinning up */ There were no changes from 2.4.20 to 2.4.22 (with 2.4.20 everything worked fine), so I guess, other timings changed. I *guess* the 30msecs was a bit strong for cd-drives in 2.4.20 too (btw. it doesnt matter, if I compile ide-scsi as module and insmod/rmmod it a few times) but worked. Somewhere in 2.4.21 things were changed somehow that modified the timing hardly enough to cross the border.
> Do I have to expect any other interferences like this?
IMHO some ide-proof should have a look at it to answer this.
regards, Mario -- Ho ho ho! I am Santa Claus of Borg. Nice assimilation all together! - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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