On Fr, 2015-01-30 at 08:40 +0100, Sascha Hauer wrote: > On Thu, Jan 29, 2015 at 08:25:54PM +0100, Robert Jarzmik wrote: > > Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> writes: > > > > > On Thu, Jan 29, 2015 at 10:12:46AM +0100, Wjatscheslaw Stoljarski > wrote: > > >> Hello, > > >> > > >> If I try to read from first 4k RAM on imx53/imx6, with md or from > code, > > >> barebox show stacktrace with mesage: > > >> "unable to handle NULL pointer dereference at address 0x...". > > >> Is it possible in some way do that? > > > > > > The only way I know is to disable CONFIG_MMU in the config. > > I think the solution in arch/arm/boards/mioa701/board.c (remapping > the 0x0 > > address) should work here : > > docg3_iospace = map_io_sections(0x0, (void *)0xe0000000, > 0x2000); > > We could create a /dev/zeropage with the code above. That would make > the zero page generally available. I don't know if this is worth the > effort though. Couldn't we special-case the zero page in /dev/mem instead? Regards, Jan -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/barebox
