Re: cache problem

[Rene B. <re...@we...>]

Ken Tyler wrote:

>
> What kernel version are you running ?


2.4.9; checkout date: 12/September

>
> Something odd in 2.4.8 caused the 53c7xx.c A4091 driver to hang my syst=
em
> at boot time but only with a modular kernel, even though 53c7xx.c is no=
t a
> module. Monolithic kernels were OK.


Hmm, I`m using a modular kernel, but the 53c770 are not compiled as a=20
module, will playing a little with that.

> And it was hanging somewhere around :
>
> memset((void *)instance->hostdata[0], 0, 8192);
> cache_push(virt_to_phys((void *)(instance->hostdata[0])), 8192);
> cache_clear(virt_to_phys((void *)(instance->hostdata[0])), 8192);
> kernel_set_cachemode(instance->hostdata[0], 8192, IOMAP_NOCACHE_SER);
>
> similar to what you have.
>
> The current 2.4.9 CVS is OK.
>
> (There are problems with the A4091 driver but that's a ZORRO bus glitch=
)

>> Then the driver starts a test where the 53c770 is exchanging some 53c7=
70
>> register values with some values in np.
>> The test fails, because np is cached!
>> If I explicitly call: flush_dcache_range(np, np + sizeof(np)); before
>> and after this test, the test doesn`t fail.
>
>
> Have a look at the tests in 53c7xx.c, they work. I noticed the use of
> barrier() in one test.


I have slightly modified the 53c7xx.c and 53c7xx.h to get it run with=20
the 53c770 chip. Because the differences between these 2 chips are not=20
very large (only some register changes). But I notice that the driver=20
test hangs at barrier()...

Is it right that you use APUS with the 53c7xx.c driver on a CSPPC?
That means that the machnism I use to get some uncached mem is working=20
on an APUS-604e machine. So whats wrong here?

I don`t understand this :-(


Ciao, Ren=E8