Right now TLB entry 0 ist used as UART0 mapping for the early debug
output (via CONFIG_SERIAL_TEXT_DEBUG). This causes problems when many
TLB's get used upon Linux bootup (e.g. while PCIe scanning behind
bridges and/or switches on 440SPe platforms). This will overwrite the
TLB 0 entry and further debug output's may crash/hang the system.
This patch moves the early debug UART0 TLB entry from 0 to 62 as done
in arch/powerpc. This way it is in the "pinned" area and will not get
overwritten. Also the arch/ppc/mm/44x_mmu.c code is now synced with the
newer code from arch/powerpc.
Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
The 44x family has an interesting "feature" which is a virtually
tagged instruction cache (yuck !). So far, we haven't dealt with
it properly, which means we've been mostly lucky or people didn't
report the problems, unless people have been running custom patches
in their distro...
This is an attempt at fixing it properly. I chose to do it by
setting a global flag whenever we change a PTE that was previously
marked executable, and flush the entire instruction cache upon
return to user space when that happens.
This is a bit heavy handed, but it's hard to do more fine grained
flushes as the icbi instruction, on those processor, for some very
strange reasons (since the cache is virtually mapped) still requires
a valid TLB entry for reading in the target address space, which
isn't something I want to deal with.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
The following patch generalizes PPC44x_PIN_SIZE by changing it to
PPC_PIN_SIZE, which can be defined by any sub-arch to automatically adjust
VMALLOC_START.
Define PPC_PIN_SIZE on 8xx, avoiding potential conflicts with the
pinned space.
Signed-off-by: Marcelo Tosatti <marcelo.tosatti@cyclades.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Continue the Good Fight: Limit bootmem.h include creep.
Signed-off-by: Jon Loeliger <jdl@freescale.com>
Signed-off-by: Kumar Gala <kumar.gala@freescale.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Stefan Roese