> > > > HIGHMEM support with full preemption has been disabled for quite some > > time on PowerPC; does anyone have any ideas as to what needs to be > > done to get it working again? > > > > Anyone got any ideas? I've been looking into adjusting the LOWMEM size to provide a 2G/2G split so I can access at least ~2GB of memory; I've got something half working but I'm now having issues with hardware access on PCIe which leads me to believe there is a mapping issue somewhere. I've adjusted PAGE_OFFSET to 0x80000000, KERNEL_START to 0x80000000, LOWMEM_SIZE to 0x70000000, LOWMEM_CAM_NUM to 7 and TASK_SIZE to 0x80000000. Linux boots and reports that it has ~1750MB RAM (as expected with the specified LOWMEM_SIZE) but these changes seem to cause issues with hardware access - no calls fail, but reads from registers on PCIe devices aren't giving correct values. Has anyone tried adjusting the LOWMEM size on PowerPC before? Are there any other gotchas I should be looking at? -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
