On 10/30/18 1:54 AM, Eugeniy Paltsev wrote: > If IOC was already enabled (due to bootloader) it technically needs to > be reconfigured with aperture base,size corresponding to Linux memory > map which will certainly be different than uboot's. But disabling and > reenabling IOC when DMA might be potentially active is tricky business. > To avoid random memory issues later, just panic here and ask user to > upgrade bootloader to one which doesn't enable IOC. > > This was actually seen as issue on some of the HSDK board with a version > of uboot which enabled IOC. There were random issues later with starting > of X or peripherals etc. > > Also while I'm at it, replace hardcoded bits in ARC_REG_IO_COH_PARTIAL > and ARC_REG_IO_COH_ENABLE registers by definitions. > > Inspired by: https://lkml.org/lkml/2018/1/19/557 > Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev at synopsys.com> > --- > Changes v1->v2: > * Fix regression: check for IOC existence before accessing to any IOC > register. > ... ... > arc_slc_disable(); > > - if (is_isa_arcv2() && ioc_enable) > + if (is_isa_arcv2() && ioc_exists) > arc_ioc_setup(); Folded this hunk into existing patch in for-curr. Thx, -Vineet
