Commit Graph

26 Commits

Author SHA1 Message Date
Stephen Rothwell 46f5221049 powerpc: Remove second definition of STACK_FRAME_OVERHEAD
Since STACK_FRAME_OVERHEAD is defined in asm/ptrace.h and that
is ASSEMBER safe, we can just include that instead of going via
asm-offsets.h.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-11-29 15:48:23 +11:00
Joakim Tjernlund 469d62be92 powerpc/8xx: Use SPRG2 and DAR registers to stash r11 and cr.
This avoids storing these registers in memory.
CPU6 errata will still use the old way.
Remove some G2 leftover accesses from 2.4

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-04-07 18:00:34 +10:00
Joakim Tjernlund d069cb4373 powerpc/8xx: Don't touch ACCESSED when no SWAP.
Only the swap function cares about the ACCESSED bit in
the pte. Do not waste cycles updateting ACCESSED when swap
is not compiled into the kernel.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-04-07 18:00:33 +10:00
Joakim Tjernlund 4afb0be7cc powerpc/8xx: Avoid testing for kernel space in ITLB Miss.
Only modules will cause ITLB Misses as we always pin
the first 8MB of kernel memory.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-04-07 18:00:32 +10:00
Joakim Tjernlund fe1691e3f4 powerpc/8xx: Optimze TLB Miss handlers
This removes a couple of insn's from the TLB Miss
handlers whithout changing functionality.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-04-07 18:00:31 +10:00
Joakim Tjernlund 061ec9599f powerpc/8xx: Fix user space TLB walk in dcbX fixup
The newly added fixup for buggy dcbX insn's has
a bug that always trigger a kernel TLB walk so a user space
dcbX insn will cause a Kernel Machine Check if it hits DTLB error.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-01-15 13:26:16 +11:00
Joakim Tjernlund 9f4f04ba2b powerpc/8xx: Always pin kernel instruction TLB
Various kernel asm modifies SRR0/SRR1 just before executing
a rfi. If such code crosses a page boundary you risk a TLB miss
which will clobber SRR0/SRR1. Avoid this by always pinning
kernel instruction TLB space.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-01-15 13:20:07 +11:00
Joakim Tjernlund 990d89c663 powerpc/8xx: DTLB Miss cleanup
Use symbolic constant for PRESENT and avoid branching.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-12-09 17:10:37 +11:00
Joakim Tjernlund 2321f33790 powerpc/8xx: Remove DIRTY pte handling in DTLB Error.
There is no need to do set the DIRTY bit directly in DTLB Error.
Trap to do_page_fault() and let the generic MM code do the work.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-12-09 17:10:37 +11:00
Joakim Tjernlund 0c4661698c powerpc/8xx: Restore _PAGE_WRITETHRU
8xx has not had WRITETHRU due to lack of bits in the pte.
After the recent rewrite of the 8xx TLB code, there are
two bits left. Use one of them to WRITETHRU.

Perhaps use the last SW bit to PAGE_SPECIAL or PAGE_FILE?

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-12-09 17:10:37 +11:00
Joakim Tjernlund 4a280a413c powerpc/8xx: Add missing Guarded setting in DTLB Error.
only DTLB Miss did set this bit, DTLB Error needs too otherwise
the setting is lost when the page becomes dirty.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-12-09 17:10:36 +11:00
Joakim Tjernlund 0a2ab51ffb powerpc/8xx: Fixup DAR from buggy dcbX instructions.
This is an assembler version to fixup DAR not being set
by dcbX, icbi instructions. There are two versions, one
uses selfmodifing code, the other uses a
jump table but is much bigger(default).

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-12-09 17:10:36 +11:00
Joakim Tjernlund 60e071fee9 powerpc/8xx: Tag DAR with 0x00f0 to catch buggy instructions.
dcbz, dcbf, dcbi, dcbst and icbi do not set DAR when they
cause a DTLB Error. Dectect this by tagging DAR with 0x00f0
at every exception exit that modifies DAR.
Test for DAR=0x00f0 in DataTLBError and bail
to handle_page_fault().

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-12-09 17:10:36 +11:00
Joakim Tjernlund fe11dc3f96 powerpc/8xx: Update TLB asm so it behaves as linux mm expects.
Update the TLB asm to make proper use of _PAGE_DIRY and _PAGE_ACCESSED.
Get rid of _PAGE_HWWRITE too.
Pros:
 - I/D TLB Miss never needs to write to the linux pte.
 - _PAGE_ACCESSED is only set on TLB Error fixing accounting
 - _PAGE_DIRTY is mapped to 0x100, the changed bit, and is set directly
    when a page has been made dirty.
 - Proper RO/RW mapping of user space.
 - Free up 2 SW TLB bits in the linux pte(add back _PAGE_WRITETHRU ?)
 - kernel RO/user NA support.
Cons:
 - A few more instructions in the TLB Miss routines.

Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-12-09 17:10:36 +11:00
Benjamin Herrenschmidt ee43eb788b powerpc: Use names rather than numbers for SPRGs (v2)
The kernel uses SPRG registers for various purposes, typically in
low level assembly code as scratch registers or to hold per-cpu
global infos such as the PACA or the current thread_info pointer.

We want to be able to easily shuffle the usage of those registers
as some implementations have specific constraints realted to some
of them, for example, some have userspace readable aliases, etc..
and the current choice isn't always the best.

This patch should not change any code generation, and replaces the
usage of SPRN_SPRGn everywhere in the kernel with a named replacement
and adds documentation next to the definition of the names as to
what those are used for on each processor family.

The only parts that still use the original numbers are bits of KVM
or suspend/resume code that just blindly needs to save/restore all
the SPRGs.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-20 10:12:27 +10:00
Tim Abbott e703984587 powerpc: convert to use __HEAD and HEAD_TEXT macros.
This has the consequence of changing the section name use for head
code from ".text.head" to ".head.text".  Since this commit changes all
users in the architecture, this change should be harmless.

Signed-off-by: Tim Abbott <tabbott@mit.edu>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-26 09:20:38 -07:00
Vitaly Bordug 76db5bd26f [POWERPC] 8xx: fix swap
This makes swap routines operate correctly on the ppc_8xx based machines.
Code has been revalidated on mpc885ads (8M sdram) with recent kernel. Based
on patch from Yuri Tikhonov <yur@emcraft.com> to do the same on arch/ppc
instance.

Recent kernel's size makes swap feature very important on low-memory platforms,
those are actually non-operable without it.

Signed-off-by: Yuri Tikhonov <yur@emcraft.com>
Signed-off-by: Vitaly Bordug <vitb@kernel.crashing.org>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-03-07 08:42:28 -06:00
Scott Wood 7401685242 [POWERPC] 8xx: Work around CPU15 erratum.
The CPU15 erratum on MPC8xx chips can cause incorrect code execution
under certain circumstances, where there is a conditional or indirect
branch in the last word of a page, with a target in the last cache line
of the next page.  This patch implements one of the suggested
workarounds, by forcing a TLB miss whenever execution crosses a page
boundary.  This is done by invalidating the pages before and after the
one being loaded into the TLB in the ITLB miss handler.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2007-10-03 20:36:36 -05:00
Scott Wood ccf0d68e83 [POWERPC] 8xx: Fix CONFIG_PIN_TLB.
1. Move CONSISTENT_START on 8xx so that it doesn't overlap the IMMR mapping.
2. The wrong register was being loaded into SPRN_MD_RPN.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2007-10-03 20:36:35 -05:00
Stephen Rothwell 19a8d97d89 [POWERPC] Remove cmd_line from head*.S
It is just a C char array, so declare it thusly.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-09-19 15:25:34 +10:00
Kumar Gala 748a768384 [POWERPC] Fix modpost warnings from head*.S on ppc32
We get warnings like the following from the various ppc32 head*.S files:

WARNING: vmlinux.o(.text+0x358): Section mismatch: reference to .init.text:early_init (between 'skpinv' and 'interrupt_base')
WARNING: vmlinux.o(.text+0x380): Section mismatch: reference to .init.text:machine_init (between 'skpinv' and 'interrupt_base')
WARNING: vmlinux.o(.text+0x384): Section mismatch: reference to .init.text:MMU_init (between 'skpinv' and 'interrupt_base')
WARNING: vmlinux.o(.text+0x3aa): Section mismatch: reference to .init.text:start_kernel (between 'skpinv' and 'interrupt_base')
WARNING: vmlinux.o(.text+0x3ae): Section mismatch: reference to .init.text:start_kernel (between 'skpinv' and 'interrupt_base')

Added a .text.head section simliar to what other architectures do since
modpost already excludes this from its warnings.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2007-09-14 08:53:36 -05:00
Jörn Engel 6ab3d5624e Remove obsolete #include <linux/config.h>
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-30 19:25:36 +02:00
Jon Mason 2ef9481e66 [PATCH] powerpc: trivial: modify comments to refer to new location of files
This patch removes all self references and fixes references to files
in the now defunct arch/ppc64 tree.  I think this accomplises
everything wanted, though there might be a few references I missed.

Signed-off-by: Jon Mason <jdmason@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-02-10 16:53:51 +11:00
Paul Mackerras d73e0c99f5 powerpc: Rename asm offset TRAP to _TRAP for 32-bit
... for consistency with 64-bit.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-10-28 22:45:25 +10:00
Stephen Rothwell dc1c1ca3dc powerpc: merge idle_power4.S and trapc.s
Use idle_power4.S from ppc64 as we are not going to support
32 bit power4 in the merged tree.

Merge ppc64 traps.c into powerpc traps.c:
	use ppc64 versions of exception routine names
		(as they don't have StudlyCaps)
	make all the versions if die() have the same
		prototype

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
2005-10-01 18:43:42 +10:00
Paul Mackerras 14cf11af6c powerpc: Merge enough to start building in arch/powerpc.
This creates the directory structure under arch/powerpc and a bunch
of Kconfig files.  It does a first-cut merge of arch/powerpc/mm,
arch/powerpc/lib and arch/powerpc/platforms/powermac.  This is enough
to build a 32-bit powermac kernel with ARCH=powerpc.

For now we are getting some unmerged files from arch/ppc/kernel and
arch/ppc/syslib, or arch/ppc64/kernel.  This makes some minor changes
to files in those directories and files outside arch/powerpc.

The boot directory is still not merged.  That's going to be interesting.

Signed-off-by: Paul Mackerras <paulus@samba.org>
2005-09-26 16:04:21 +10:00