Date: Sat, 12 Aug 2006 11:42:30 +0300 From: Niki Denev <nike_d@cytexbg.com> To: John Baldwin <jhb@freebsd.org> Cc: freebsd-hackers@freebsd.org Subject: Re: jkh weird problem (reading pci device memory) Message-ID: <44DD9476.7020706@cytexbg.com> In-Reply-To: <200608071527.50711.jhb@freebsd.org> References: <44D4A5DC.7080403@cytexbg.com> <200608071527.50711.jhb@freebsd.org>
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John Baldwin wrote:
> On Saturday 05 August 2006 10:06, Niki Denev wrote:
>> for(i=0; i < sizeof(config_table_t); i++) {
>> r = bus_space_read_1(sc->bar.tag, sc->bar.hdl, i);
>> *((u_int8_t *)&sc->cfg_table + i) = r;
>> }
>
> Note that you can replace this with:
>
> bus_space_read_multi_1(sc->bar.tag, sc->bar.hdl, 0,
> (u_int8_t *)&sc->cfg_table, sizeof(config_table_t));
>
I can't understand why the code above gives me different results.
i.e.:
for(i=0; i < sizeof(config_table_t); i++) {
*((u_int8_t *)&sc->cfg_table + i) = bus_read_1(sc->res, i);
}
printf("cfg_table signature : %08X\n", sc->cfg_table.signature);
This prints : cfg_table signaature 0xEFEFFEFE, which is the correct signature
that should be read from the card.
But this code :
bus_read_multi_1(sc->res, 0, (u_int8_t *)&sc->cfg_table, sizeof(config_table_t));
printf("cfg_table signature : %08X\n", sc->cfg_table.signature);
prints : cfg_table signature 0xFEFEFEFE
which is not correct...
Shouldn't the above examples do exactly the same thing?
- --niki
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