Hi Mike, On Tue, Mar 16, 2021 at 11:33 PM Mike Rapoport <r...@kernel.org> wrote: > > Hi Ilya, > > On Tue, Mar 16, 2021 at 10:10:09PM -0700, Ilya Lipnitskiy wrote: > > Hi Thomas, > > > > On Fri, Mar 12, 2021 at 7:19 AM Thomas Bogendoerfer > > <tsbog...@alpha.franken.de> wrote: > > > > > > On Sun, Mar 07, 2021 at 11:40:30AM -0800, Ilya Lipnitskiy wrote: > > > > From: Tobias Wolf <dev-n...@vplace.de> > > > > > > > > Commit 67a3ba25aa95 ("MIPS: Fix incorrect mem=X@Y handling") introduced > > > > a new > > > > issue for rt288x where "PHYS_OFFSET" is 0x0 but the calculated > > > > "ramstart" is > > > > not. As the prerequisite of custom memory map has been removed, this > > > > results > > > > in the full memory range of 0x0 - 0x8000000 to be marked as reserved > > > > for this > > > > platform. > > > > > > and where is the problem here ? > > Turns out this was already attempted to be upstreamed - not clear why > > it wasn't merged. Context: > > https://lore.kernel.org/linux-mips/6504517.U6H5IhoIOn@loki/ > > > > I hope the thread above helps you understand the problem. > > The memory initialization was a bit different then. Do you still see the > same problem? Thanks for asking. I obtained a RT2880 device and gave it a try. It hangs at boot without this patch, however selecting MIPS_AUTO_PFN_OFFSET fixes it. Also, no more messages like "Wasting 1048576 bytes for tracking 32768 unused pages". MIPS_AUTO_PFN_OFFSET was suggested by Paul Burton here: https://lore.kernel.org/linux-mips/20180820233111.xww5232dxbuouf4n@pburton-laptop/
I will supersede this patch with one that simply selects MIPS_AUTO_PFN_OFFSET for this SOC. Ilya