Le 11/11/2022 à 15:27, Steven J. Hill a écrit : > On 11/11/22 02:53, Christophe Leroy wrote: >> >> First of all, kernel 3.12 is prehistoric. Have you tried with latest >> kernel, or at least with one of the long term support releases (see >> https://www.kernel.org/category/releases.html) ? >> > It is what my customer wants. For this project, upgrading the kernel is > not an option. I am using the IO accessor out_be32() along with a BAT:
That's maybe not an option for your customer, but it is a good option for yourself to find out what the problem is. If recent kernel don't have the problem, you can then perform a 'git bisect' in order to find out which commit fixed the problem. Once that is done, you may backport the fixing commit to 3.12 for your customer. > > setbat(6, 0xe50000000, 0xe5000000, 4096*1024, PAGE_KERNEL_NCG); Have you tried with ioremap() instead of setbat() ? Also, what other BATs do you have in your setup ? Maybe you have some overlapping BATs. Christophe
