Commit Graph

57 Commits

Author SHA1 Message Date
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Christophe Leroy 1a4b739bbb powerpc/32: implement fast entry for syscalls on BOOKE
This patch implements a fast entry for syscalls.

Syscalls don't have to preserve non volatile registers except LR.

This patch then implement a fast entry for syscalls, where
volatile registers get clobbered.

As this entry is dedicated to syscall it always sets MSR_EE
and warns in case MSR_EE was previously off

It also assumes that the call is always from user, system calls are
unexpected from kernel.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:27 +10:00
Christophe Leroy 642770dd96 powerpc/32: Enter exceptions with MSR_EE unset
All exceptions handlers know when to reenable interrupts, so
it is safer to enter all of them with MSR_EE unset, except
for syscalls.

Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[splited out from benh RFC patch]

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:27 +10:00
Christophe Leroy f97dec21a3 powerpc/32: enter syscall with MSR_EE inconditionaly set
syscalls are expected to be entered with MSR_EE set. Lets
make it inconditional by forcing MSR_EE on syscalls.

This patch adds EXC_XFER_SYS for that.

Suggested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[splited out from benh RFC patch]

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:27 +10:00
Christophe Leroy 2edb16efc8 powerpc/32: Add KASAN support
This patch adds KASAN support for PPC32. The following patch
will add an early activation of hash table for book3s. Until
then, a warning will be raised if trying to use KASAN on an
hash 6xx.

To support KASAN, this patch initialises that MMU mapings for
accessing to the KASAN shadow area defined in a previous patch.

An early mapping is set as soon as the kernel code has been
relocated at its definitive place.

Then the definitive mapping is set once paging is initialised.

For modules, the shadow area is allocated at module_alloc().

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03 01:20:26 +10:00
Christophe Leroy 7c19c2e5f9 powerpc: 'current_set' is now a table of task_struct pointers
The table of pointers 'current_set' has been used for retrieving
the stack and current. They used to be thread_info pointers as
they were pointing to the stack and current was taken from the
'task' field of the thread_info.

Now, the pointers of 'current_set' table are now both pointers
to task_struct and pointers to thread_info.

As they are used to get current, and the stack pointer is
retrieved from current's stack field, this patch changes
their type to task_struct, and renames secondary_ti to
secondary_current.

Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:40 +11:00
Christophe Leroy ed1cd6deb0 powerpc: Activate CONFIG_THREAD_INFO_IN_TASK
This patch activates CONFIG_THREAD_INFO_IN_TASK which
moves the thread_info into task_struct.

Moving thread_info into task_struct has the following advantages:
  - It protects thread_info from corruption in the case of stack
    overflows.
  - Its address is harder to determine if stack addresses are leaked,
    making a number of attacks more difficult.

This has the following consequences:
  - thread_info is now located at the beginning of task_struct.
  - The 'cpu' field is now in task_struct, and only exists when
    CONFIG_SMP is active.
  - thread_info doesn't have anymore the 'task' field.

This patch:
  - Removes all recopy of thread_info struct when the stack changes.
  - Changes the CURRENT_THREAD_INFO() macro to point to current.
  - Selects CONFIG_THREAD_INFO_IN_TASK.
  - Modifies raw_smp_processor_id() to get ->cpu from current without
    including linux/sched.h to avoid circular inclusion and without
    including asm/asm-offsets.h to avoid symbol names duplication
    between ASM constants and C constants.
  - Modifies klp_init_thread_info() to take a task_struct pointer
    argument.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Add task_stack.h to livepatch.h to fix build fails]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:40 +11:00
Christophe Leroy 4e67bfd7aa powerpc: Update comments in preparation for THREAD_INFO_IN_TASK
Update a few comments that talk about current_thread_info() in
preparation for THREAD_INFO_IN_TASK.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Split out of larger patch]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:40 +11:00
Christophe Leroy 6c16816b91 powerpc/44x: use patch_sites for TLB handlers patching
Use patch sites and associated helpers to manage TLB handlers
patching instead of hardcoding.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 18:56:32 +11:00
Al Viro 9445aa1a30 ppc: move exports to definitions
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-08-07 23:50:09 -04:00
Adam Buchbinder 446957ba51 powerpc: Fix misspellings in comments.
Signed-off-by: Adam Buchbinder <adam.buchbinder@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-01 19:27:20 +11:00
Alistair Popple 97b3be1e94 powerpc/ppc476: Disable BTAC
This patch disables the branch target address CAM which under specific
circumstances may cause the processor to skip execution of 1-4
instructions. This fixes IBM Erratum #47.

Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-13 15:13:42 +10:00
Kevin Hao 5f20be4478 powerpc: Remove the empty giveup_fpu() function on 32bit kernel
Instead of implementing an empty giveup_fpu() function for each
32bit processor type, replace them with an unique empty inline
function.

Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-08-14 14:59:50 +10:00
Bharat Bhushan fc2a6cfe05 powerpc: Fix interrupt range check on debug exception
We do not want to take single step and branch-taken debug exception
in kernel exception code. But the address range check was not covering
all kernel exception handlers address range.

With this patch we defined the interrupt_end label which defines the
end on kernel exception code. So now we check interrupt_base to
interrupt_end range for not handling debug exception in kernel
exception entry.

Signed-off-by: Bharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-05-02 10:31:01 +10:00
Linus Torvalds 07acfc2a93 Merge branch 'next' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM changes from Avi Kivity:
 "Changes include additional instruction emulation, page-crossing MMIO,
  faster dirty logging, preventing the watchdog from killing a stopped
  guest, module autoload, a new MSI ABI, and some minor optimizations
  and fixes.  Outside x86 we have a small s390 and a very large ppc
  update.

  Regarding the new (for kvm) rebaseless workflow, some of the patches
  that were merged before we switch trees had to be rebased, while
  others are true pulls.  In either case the signoffs should be correct
  now."

Fix up trivial conflicts in Documentation/feature-removal-schedule.txt
arch/powerpc/kvm/book3s_segment.S and arch/x86/include/asm/kvm_para.h.

I suspect the kvm_para.h resolution ends up doing the "do I have cpuid"
check effectively twice (it was done differently in two different
commits), but better safe than sorry ;)

* 'next' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (125 commits)
  KVM: make asm-generic/kvm_para.h have an ifdef __KERNEL__ block
  KVM: s390: onereg for timer related registers
  KVM: s390: epoch difference and TOD programmable field
  KVM: s390: KVM_GET/SET_ONEREG for s390
  KVM: s390: add capability indicating COW support
  KVM: Fix mmu_reload() clash with nested vmx event injection
  KVM: MMU: Don't use RCU for lockless shadow walking
  KVM: VMX: Optimize %ds, %es reload
  KVM: VMX: Fix %ds/%es clobber
  KVM: x86 emulator: convert bsf/bsr instructions to emulate_2op_SrcV_nobyte()
  KVM: VMX: unlike vmcs on fail path
  KVM: PPC: Emulator: clean up SPR reads and writes
  KVM: PPC: Emulator: clean up instruction parsing
  kvm/powerpc: Add new ioctl to retreive server MMU infos
  kvm/book3s: Make kernel emulated H_PUT_TCE available for "PR" KVM
  KVM: PPC: bookehv: Fix r8/r13 storing in level exception handler
  KVM: PPC: Book3S: Enable IRQs during exit handling
  KVM: PPC: Fix PR KVM on POWER7 bare metal
  KVM: PPC: Fix stbux emulation
  KVM: PPC: bookehv: Use lwz/stw instead of PPC_LL/PPC_STL for 32-bit fields
  ...
2012-05-24 16:17:30 -07:00
Anton Blanchard 8cd3c23df7 powerpc: Remove empty giveup_altivec function on book3e CPUs
Use an empty inline instead of an empty function to implement
giveup_altivec on book3e CPUs, similar to flush_altivec_to_thread.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2012-04-30 15:37:16 +10:00
Scott Wood cfac57847a powerpc/booke: Provide exception macros with interrupt name
DO_KVM will need to identify the particular exception type.

There is an existing set of arbitrary numbers that Linux passes,
but it's an undocumented mess that sort of corresponds to server/classic
exception vectors but not really.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-04-08 12:51:17 +03:00
Suzuki Poulose 26ecb6c44b powerpc/44x: Enable CONFIG_RELOCATABLE for PPC44x
The following patch adds relocatable kernel support - based on processing
of dynamic relocations - for PPC44x kernel.

We find the runtime address of _stext and relocate ourselves based
on the following calculation.

	virtual_base = ALIGN(KERNELBASE,256M) +
			MODULO(_stext.run,256M)

relocate() is called with the Effective Virtual Base Address (as
shown below)

            | Phys. Addr| Virt. Addr |
Page (256M) |------------------------|
Boundary    |           |            |
            |           |            |
            |           |            |
Kernel Load |___________|_ __ _ _ _ _|<- Effective
Addr(_stext)|           |      ^     |Virt. Base Addr
            |           |      |     |
            |           |      |     |
            |           |reloc_offset|
            |           |      |     |
            |           |      |     |
            |           |______v_____|<-(KERNELBASE)%256M
            |           |            |
            |           |            |
            |           |            |
Page(256M)  |-----------|------------|
Boundary    |           |            |

The virt_phys_offset is updated accordingly, i.e,

	virt_phys_offset = effective. kernel virt base - kernstart_addr

I have tested the patches on 440x platforms only. However this should
work fine for PPC_47x also, as we only depend on the runtime address
and the current TLB XLAT entry for the startup code, which is available
in r25. I don't have access to a 47x board yet. So, it would be great if
somebody could test this on 47x.

Signed-off-by: Suzuki K. Poulose <suzuki@in.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Tony Breeds <tony@bakeyournoodle.com>
Cc: Josh Boyer <jwboyer@gmail.com>
Cc: linuxppc-dev <linuxppc-dev@lists.ozlabs.org>
Signed-off-by: Josh Boyer <jwboyer@gmail.com>
2011-12-20 10:21:57 -05:00
Suzuki Poulose 2391324545 powerpc/44x: Enable DYNAMIC_MEMSTART for 440x
DYNAMIC_MEMSTART(old RELOCATABLE) was restricted only to PPC_47x variants
of 44x. This patch enables DYNAMIC_MEMSTART for 440x based chipsets.

Signed-off-by: Suzuki K. Poulose <suzuki@in.ibm.com>
Cc: Josh Boyer <jwboyer@gmail.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: linux ppc dev <linuxppc-dev@lists.ozlabs.org>
Signed-off-by: Josh Boyer <jwboyer@gmail.com>
2011-12-20 10:20:38 -05:00
Suzuki Poulose 0f890c8d20 powerpc: Rename mapping based RELOCATABLE to DYNAMIC_MEMSTART for BookE
The current implementation of CONFIG_RELOCATABLE in BookE is based
on mapping the page aligned kernel load address to KERNELBASE. This
approach however is not enough for platforms, where the TLB page size
is large (e.g, 256M on 44x). So we are renaming the RELOCATABLE used
currently in BookE to DYNAMIC_MEMSTART to reflect the actual method.

The CONFIG_RELOCATABLE for PPC32(BookE) based on processing of the
dynamic relocations will be introduced in the later in the patch series.

This change would allow the use of the old method of RELOCATABLE for
platforms which can afford to enforce the page alignment (platforms with
smaller TLB size).

Changes since v3:

* Introduced a new config, NONSTATIC_KERNEL, to denote a kernel which is
  either a RELOCATABLE or DYNAMIC_MEMSTART(Suggested by: Josh Boyer)

Suggested-by: Scott Wood <scottwood@freescale.com>
Tested-by: Scott Wood <scottwood@freescale.com>

Signed-off-by: Suzuki K. Poulose <suzuki@in.ibm.com>
Cc: Scott Wood <scottwood@freescale.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Josh Boyer <jwboyer@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: linux ppc dev <linuxppc-dev@lists.ozlabs.org>
Signed-off-by: Josh Boyer <jwboyer@gmail.com>
2011-12-20 10:20:19 -05:00
Tony Breeds df777bd39a powerpc/476fpe: Add 476fpe SoC code
Based on original work by David 'Shaggy' Kleikamp.

Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Josh Boyer <jwboyer@gmail.com>
2011-12-09 07:51:02 -05:00
Scott Wood 6dece0eb69 powerpc/32: Pass device tree address as u64 to machine_init
u64 is used rather than phys_addr_t to keep things simple, as
this is called from assembly code.

Update callers to pass a 64-bit address in r3/r4.  Other unused
register assignments that were once parameters to machine_init
are dropped.

For FSL BookE, look up the physical address of the device tree from the
effective address passed in r3 by the loader.  This is required for
situations where memory does not start at zero (due to AMP or IOMMU-less
virtualization), and thus the IMA doesn't start at zero, and thus the
device tree effective address does not equal the physical address.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-09-20 09:19:47 +10:00
Dave Kleikamp 9661534d6a powerpc/47x: allow kernel to be loaded in higher physical memory
The 44x code (which is shared by 47x) assumes the available physical memory
begins at 0x00000000.  This is not necessarily the case in an AMP
environment.

Support CONFIG_RELOCATABLE for 476 in order to allow the kernel to be
loaded into a higher memory range.

Signed-off-by: Tony Breeds <tony@bakeyournoodle.com>
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2011-07-12 10:34:24 -04:00
Lucas De Marchi 25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
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
Dave Kleikamp 029b8f662b powerpc/47x: Make sure mcsr is cleared before enabling machine check interrupts
Clear the machine check syndrom register before enabling machine check
interrupts.  The initial state of the tlb can lead to parity errors being
flagged early after a cold boot.

Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2010-08-23 07:36:58 -04:00
Torez Smith b4e8c8dd84 powerpc/4xx: Simple platform for the ISS 4xx simulator
This is a trivial 4xx plaform that uses the new simple bsp from
Josh and is handy to use in simulators such as ISS or even Mambo
who don't properly implement most of the actual devices in the
SoC but really only the core.

Signed-off-by: Torez Smith  <lnxtorez@linux.vnet.ibm.com>
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2010-05-05 11:11:56 -04:00
Dave Kleikamp e7f75ad01d powerpc/47x: Base ppc476 support
This patch adds the base support for the 476 processor.  The code was
primarily written by Ben Herrenschmidt and Torez Smith, but I've been
maintaining it for a while.

The goal is to have a single binary that will run on 44x and 47x, but
we still have some details to work out.  The biggest is that the L1 cache
line size differs on the two platforms, but it's currently a compile-time
option.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Torez Smith  <lnxtorez@linux.vnet.ibm.com>
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2010-05-05 09:11:10 -04:00
Dave Kleikamp 795033c344 powerpc/44x: break out cpu init code into stand-alone function
The 47x platform supports multiple cores and shares code with 44x.
Break out code that is common for initializing the primary and secondary
cpus into a function which can be called for both.

Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2010-05-05 08:04:36 -04:00
Benjamin Herrenschmidt ea3cc330ac powerpc/mm: Cleanup handling of execute permission
This is an attempt at cleaning up a bit the way we handle execute
permission on powerpc. _PAGE_HWEXEC is gone, _PAGE_EXEC is now only
defined by CPUs that can do something with it, and the myriad of
#ifdef's in the I$/D$ coherency code is reduced to 2 cases that
hopefully should cover everything.

The logic on BookE is a little bit different than what it was though
not by much. Since now, _PAGE_EXEC will be set by the generic code
for executable pages, we need to filter out if they are unclean and
recover it. However, I don't expect the code to be more bloated than
it already was in that area due to that change.

I could boast that this brings proper enforcing of per-page execute
permissions to all BookE and 40x but in fact, we've had that now for
some time as a side effect of my previous rework in that area (and
I didn't even know it :-) We would only enable execute permission if
the page was cache clean and we would only cache clean it if we took
and exec fault. Since we now enforce that the later only work if
VM_EXEC is part of the VMA flags, we de-fact already enforce per-page
execute permissions... Unless I missed something

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-08-27 13:12:51 +10:00
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
Ilya Yanok ca9153a3a2 powerpc/44x: Support 16K/64K base page sizes on 44x
This adds support for 16k and 64k page sizes on PowerPC 44x processors.

The PGDIR table is much smaller than a page when using 16k or 64k
pages (512 and 32 bytes respectively) so we allocate the PGDIR with
kzalloc() instead of __get_free_pages().

One PTE table covers rather a large memory area when using 16k or 64k
pages (32MB or 512MB respectively), so we can easily put FIXMAP and
PKMAP in the area covered by one PTE table.

Signed-off-by: Yuri Tikhonov <yur@emcraft.com>
Signed-off-by: Vladimir Panfilov <pvr@emcraft.com>
Signed-off-by: Ilya Yanok <yanok@emcraft.com>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-12-29 09:53:25 +11:00
Benjamin Herrenschmidt 9dce3ce5c5 powerpc/44x: 44x TLB doesn't need "Guarded" set for all pages
After discussing with chip designers, it appears that it's not
necessary to set G everywhere on 440 cores. The various core
errata related to prefetch should be sorted out by firmware by
disabling icache prefetching in CCR0. We add the workaround to
the kernel however just in case oooold firmwares don't do it.

This is valid for -all- 4xx core variants. Later ones hard wire
the absence of prefetch but it doesn't harm to clear the bits
in CCR0 (they should already be cleared anyway).

We still leave G=1 on the linear mapping for now, we need to
stop over-mapping RAM to be able to remove it.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-12-21 14:21:16 +11:00
Benjamin Herrenschmidt 64b3d0e812 powerpc/mm: Rework usage of _PAGE_COHERENT/NO_CACHE/GUARDED
Currently, we never set _PAGE_COHERENT in the PTEs, we just OR it in
in the hash code based on some CPU feature bit.  We also manipulate
_PAGE_NO_CACHE and _PAGE_GUARDED by hand in all sorts of places.

This changes the logic so that instead, the PTE now contains
_PAGE_COHERENT for all normal RAM pages thay have I = 0 on platforms
that need it.  The hash code clears it if the feature bit is not set.

It also adds some clean accessors to setup various valid combinations
of access flags and change various bits of code to use them instead.

This should help having the PTE actually containing the bit
combinations that we really want.

I also removed _PAGE_GUARDED from _PAGE_BASE on 44x and instead
set it explicitely from the TLB miss.  I will ultimately remove it
completely as it appears that it might not be needed after all
but in the meantime, having it in the TLB miss makes things a
lot easier.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-12-21 14:21:16 +11:00
Benjamin Herrenschmidt 1bc54c0311 powerpc: rework 4xx PTE access and TLB miss
This is some preliminary work to improve TLB management on SW loaded
TLB powerpc platforms. This introduce support for non-atomic PTE
operations in pgtable-ppc32.h and removes write back to the PTE from
the TLB miss handlers. In addition, the DSI interrupt code no longer
tries to fixup write permission, this is left to generic code, and
_PAGE_HWWRITE is gone.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2008-07-09 13:36:17 -04:00
Paul Mackerras e9a4b6a3f6 Merge branch 'linux-2.6' 2008-06-30 10:16:50 +10:00
Josh Boyer b17879f71c [POWERPC] 4xx: Clear new TLB cache attribute bits in Data Storage vector
A recent commit added support for the new 440x6 and 464 cores that have the
added WL1, IL1I, IL1D, IL2I, and ILD2 bits for the caching attributes in the
TLBs.  The new bits were cleared in the finish_tlb_load function, however a
similar bit of code was missed in the DataStorage interrupt vector.

Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2008-06-18 21:40:43 +10:00
Kumar Gala bcf0b08807 [POWERPC] Move to runtime allocated exception stacks
For the additonal exception levels (critical, debug, machine check) on
40x/book-e we were using "static" allocations of the stack in the
associated head.S.

Move to a runtime allocation to make the code a bit easier to read as
we mimic how we handle IRQ stacks.  Its also a bit easier to setup the
stack with a "dummy" thread_info in C code.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Paul Mackerras <paulus@samba.org>
2008-06-02 14:54:42 -05:00
Stefan Roese a96df496ed [POWERPC] 4xx: Fix problem with new TLB storage attibute fields on 440x6 core
The new 440x6 core used on AMCC 460EX/GT introduces new storage attibure
fields to the TLB2 word. Those are:

Bit  11   12   13   14   15
     WL1  IL1I IL1D IL2I IL2D

With these bits the cache (L1 and L2) can be configured in a more flexible
way, instruction- and data-cache independently now. The "old" I and W bits
are still available and setting these old bits will automically set these
new bits too (for backward compatibilty).

The current code does not clear these fields resulting in disabling the cache
by chance. This patch now makes sure that these new bits are cleared when
the TLB2 word is written.

Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2008-05-06 10:36:20 -05:00
Kumar Gala eb0cd5fd29 [POWERPC] Rework Book-E debug exception handling
The architecture allows for "Book-E" style debug interrupts to either go
to critial interrupts of their own debug interrupt level.  To allow for
a dynamic kernel to support machines of either type we want to be able to
compile in the interrupt handling code for both exception levels.

Towards this goal we renamed the debug handling macros to specify the
interrupt level in their name (DEBUG_CRIT_EXCEPTION/DebugCrit and
DEBUG_DEBUG_EXCEPTION/DebugDebug).

Additionally, on the Freescale Book-e parts we expanded the exception
stacks to cover the maximum case of needing three exception stacks (normal,
machine check and debug).

There is some kernel text space optimization to be gained if a kernel is
configured for a specific Freescale implementation but we aren't handling
that now to allow for the single kernel image support.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2008-04-17 01:01:36 -05:00
Benjamin Herrenschmidt 47c0bd1ae2 [POWERPC] Reworking machine check handling and Fix 440/440A
This adds a cputable function pointer for the CPU-side machine
check handling. The semantic is still the same as the old one,
the one in ppc_md. overrides the one in cputable, though
ultimately we'll want to change that so the CPU gets first.

This removes CONFIG_440A which was a problem for multiplatform
kernels and instead fixes up the IVOR at runtime from a setup_cpu
function. The "A" version of the machine check also tweaks the
regs->trap value to differenciate the 2 versions at the C level.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2007-12-23 13:11:59 -06:00
Kumar Gala bee86f14d5 [POWERPC] Fix swapper_pg_dir size when CONFIG_PTE_64BIT=y on FSL_BOOKE
The size of swapper_pg_dir is 8k instead of 4k when using 64-bit PTEs
(CONFIG_PTE_64BIT).

This was reported by Cedric Hombourger <chombourger@gmail.com>

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2007-12-06 13:11:04 -06:00
Kumar Gala 8a13c4f972 [POWERPC] Use PAGE_OFFSET to tell if an address is user/kernel in SW TLB handlers
Move to using PAGE_OFFSET instead of TASK_SIZE or KERNELBASE value on
6xx/40x/44x/fsl-booke to determine if the faulting address is a kernel or
user space address.  This mimics how the macro is_kernel_addr() works.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
2007-10-11 13:36:52 -05:00
Valentine Barshak 8112753bb2 [POWERPC] 4xx: Move 440EP(x) FPU setup from head_44x to cpu_setup_4xx
The PowerPC 440EP(x) FPU init is currently done in head_44x
under ifdefs. Since we should support more then one board
in the same kernel, we move FPU initialization code from head_44x
to cpu_setup_44x and add cpu_setup callbacks for 440EP(x).

Signed-off-by: Valentine Barshak <vbarshak@ru.mvista.com>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2007-10-03 07:20:17 -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
Valentine Barshak 15fc993e31 [POWERPC] PowerPC 440EPx: Sequoia board support
AMCC PPC440EPx Sequoia board support.

Signed-off-by: Valentine Barshak <vbarshak@ru.mvista.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
2007-09-07 07:49:13 -05:00
David Gibson d9b55a0361 [POWERPC] Early serial debug support for PPC44x
This adds support for early serial debugging via the built in
port on IBM/AMCC PowerPC 44x CPUs.  It uses a bolted TLB entry in
address space 1 for the UART's mapping, allowing robust debugging both
before and after the initialization of the MMU.

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-05-08 14:47:33 +10:00
David Gibson 2cd9764770 [POWERPC] Add powerpc/platforms/44x, disable platforms/4xx for now
This prepares for Ebony/440 support by creating an
arch/powerpc/platforms/44x directory.  It is populated with a single
misc_44x.S file, into which is moved the 44x specific reset code from
head_44x.S (on the grounds that we should really stop clogging up the
head_* files with random asm helper routines).

At the same time, we disable the (empty save Kconfig and Makefile)
arch/powerpc/platforms/4xx directory from the arch/powerpc/platforms
Makefile.  Contrary to the comment in
arch/powerpc/platforms/4xx/Makefile, attempting to build such an empty
Makefile will fail, thus breaking compile for the 44x platforms we're
about to add.  It can go back in once we start porting some of the 40x
platforms (and thus it becomes non-empty).

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-05-08 14:43:59 +10:00