Date: Mon, 7 Aug 2006 15:05:51 -0700 From: John-Mark Gurney <gurney_j@resnet.uoregon.edu> To: John Baldwin <jhb@freebsd.org> Cc: freebsd-hackers@freebsd.org Subject: Re: jkh weird problem (reading pci device memory) Message-ID: <20060807220550.GF99774@funkthat.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 this message on Mon, Aug 07, 2006 at 15:27 -0400: > sc->cfg_table.signature = letoh32(bus_read_4(sc->bar.res, 0)); > sc->cfg_table.version = letoh16(bus_read_2(sc->bar.res, 4)); > sc->cfg_table.dummy = bus_read_1(sc->bar.res, 5); Note that this may or may not be correct... the bus_read_X macros do endian conversion if the bus is of different endianness than the processor arch... So if the device is on a PCI bus, and the machine is sparc64, the bus_read_X will already be swapped as necessary... If you don't want the byte swapping to be done for you, there are the _stream versions... The are useful for transfering data like disk data that needs to maintain the same order... -- John-Mark Gurney Voice: +1 415 225 5579 "All that I will do, has been done, All that I have, has not."
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