Commit Graph

34 Commits

Author SHA1 Message Date
Christophe Leroy
1ca9db5b65 powerpc/32: save DEAR/DAR before calling handle_page_fault
handle_page_fault() is the only function that save DAR/DEAR itself.

Save DAR/DEAR before calling handle_page_fault() to prepare for
VMAP stack which will require to save even before.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/3a4d58d378091086f00fde42b59610c80289e120.1576916812.git.christophe.leroy@c-s.fr
2020-01-26 22:15:09 +11:00
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
b86fb88855 powerpc/32: implement fast entry for syscalls on non 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.

The overall series improves null_syscall selftest by 12,5% on an 83xx
and by 17% on a 8xx.

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
1ae99b4b92 powerpc/32: get rid of COPY_EE in exception entry
EXC_XFER_TEMPLATE() is not called with COPY_EE anymore so
we can get rid of copyee parameters and related COPY_EE and NOCOPY
macros.

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
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
90f204b9a1 powerpc/40x: Refactor exception entry macros by using head_32.h
Refactor exception entry macros by using the ones defined in head_32.h

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
7271fc9604 powerpc/40x: Split and rename NORMAL_EXCEPTION_PROLOG
This patch splits NORMAL_EXCEPTION_PROLOG in the same way as in
head_8xx.S and head_32.S and renames it EXCEPTION_PROLOG() as well
to match head_32.h

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
bd82904d46 powerpc/40x: add exception frame marker
This patch adds STACK_FRAME_REGS_MARKER in the stack at exception entry
in order to see interrupts in call traces as below:

[    0.013964] Call Trace:
[    0.014014] [c0745db0] [c007a9d4] tick_periodic.constprop.5+0xd8/0x104 (unreliable)
[    0.014086] [c0745dc0] [c007aa20] tick_handle_periodic+0x20/0x9c
[    0.014181] [c0745de0] [c0009cd0] timer_interrupt+0xa0/0x264
[    0.014258] [c0745e10] [c000e484] ret_from_except+0x0/0x14
[    0.014390] --- interrupt: 901 at console_unlock.part.7+0x3f4/0x528
[    0.014390]     LR = console_unlock.part.7+0x3f0/0x528
[    0.014455] [c0745ee0] [c0050334] console_unlock.part.7+0x114/0x528 (unreliable)
[    0.014542] [c0745f30] [c00524e0] register_console+0x3d8/0x44c
[    0.014625] [c0745f60] [c0675aac] cpm_uart_console_init+0x18/0x2c
[    0.014709] [c0745f70] [c06614f4] console_init+0x114/0x1cc
[    0.014795] [c0745fb0] [c0658b68] start_kernel+0x300/0x3d8
[    0.014864] [c0745ff0] [c00022cc] start_here+0x44/0x98

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
57bc13acbe powerpc/40x: Don't use SPRN_SPRG_SCRATCH2 in EXCEPTION_PROLOG
Unlike said in the comment, r1 is not reused by the critical
exception handler, as it uses a dedicated critirq_ctx stack.
Decrementing r1 early is then unneeded.

Should the above be valid, the code is crap buggy anyway as
r1 gets some intermediate values that would jeopardise the
whole process (for instance after mfspr   r1,SPRN_SPRG_THREAD)

Using SPRN_SPRG_SCRATCH2 to save r1 is then not needed, r11 can be
used instead. This avoids one mtspr and one mfspr and makes the
prolog closer to what's done on 6xx and 8xx.

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
8c1fc5abdc powerpc: Rename THREAD_INFO to TASK_STACK
This patch renames THREAD_INFO to TASK_STACK, because it is in fact
the offset of the pointer to the stack in task_struct so this pointer
will not be impacted by the move of THREAD_INFO.

Also make it available on 64-bit, as we'll need it there when we
activate THREAD_INFO_IN_TASK.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Make available on 64-bit]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-23 22:31:40 +11:00
Christophe Leroy
40058337f2 powerpc: simplify BDI switch
There is no reason to re-read each time the pointer at
location 0xf0 as it is fixed and known.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-22 00:10:16 +11:00
Christophe Leroy
36a7eeaff7 powerpc/405: move PPC405_ERR77 in asm-405.h
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-07-30 22:48:13 +10:00
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
Paul Bolle
94314290ed powerpc: Remove check for CONFIG_SERIAL_TEXT_DEBUG
The Kconfig symbol SERIAL_TEXT_DEBUG was removed from
arch/powerpc/Kconfig.debug in v2.6.22. (In v2.6.27 it was also removed
from arch/ppc/Kconfig.debug.) So the check for its macro has evaluated
to false for over five years now. Remove that check and the few lines
of code hidden behind it.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-06-11 16:31:21 +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
Jason Gunthorpe
1e18c17adf powerpc: Enable the Watchdog vector for 405
The watchdog and FIT code has been #if 0'd for ever, if the CPU takes
an exception to either of those vectors it will jump into the middle
of the PIT or Data TLB code and surely crash.

At least some (all?) 405 cores have both the WDT and FIT
vectors defined, so lets have proper entry points for them.

Tested that the WDT vector works on a 405F6 core.

Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-01-10 14:43:46 +11:00
Benjamin Herrenschmidt
a546498f3b powerpc: Call do_page_fault() with interrupts off
We currently turn interrupts back to their previous state before
calling do_page_fault(). This can be annoying when debugging as
a bad fault will potentially have lost some processor state before
getting into the debugger.

We also end up calling some generic code with interrupts enabled
such as notify_page_fault() with interrupts enabled, which could
be unexpected.

This changes our code to behave more like other architectures,
and make the assembly entry code call into do_page_faults() with
interrupts disabled. They are conditionally re-enabled from
within do_page_fault() in the same spot x86 does it.

While there, add the might_sleep() test in the case of a successful
trylock of the mmap semaphore, again like x86.

Also fix a bug in the existing assembly where r12 (_MSR) could get
clobbered by C calls (the DTL accounting in the exception common
macro and DISABLE_INTS) in some cases.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---

v2. Add the r12 clobber fix
2012-03-09 10:55:08 +11:00
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
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
Benjamin Herrenschmidt
cd3db0c4ca memblock: Remove rmo_size, burry it in arch/powerpc where it belongs
The RMA (RMO is a misnomer) is a concept specific to ppc64 (in fact
server ppc64 though I hijack it on embedded ppc64 for similar purposes)
and represents the area of memory that can be accessed in real mode
(aka with MMU off), or on embedded, from the exception vectors (which
is bolted in the TLB) which pretty much boils down to the same thing.

We take that out of the generic MEMBLOCK data structure and move it into
arch/powerpc where it belongs, renaming it to "RMA" while at it.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2010-08-05 12:56:08 +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
Kumar Gala
fca622c5b2 [POWERPC] 40x/Book-E: Save/restore volatile exception registers
On machines with more than one exception level any system register that
might be modified by the "normal" exception level needs to be saved and
restored on taking a higher level exception.  We already are saving
and restoring ESR and DEAR.

For critical level add SRR0/1.
For debug level add CSRR0/1 and SRR0/1.
For machine check level add DSRR0/1, CSRR0/1, and SRR0/1.

On FSL Book-E parts we always save/restore the MAS registers for critical,
debug, and machine check level exceptions.  On 44x we always save/restore
the MMUCR.

Additionally, we save and restore the ksp_limit since we have to adjust it
for each exception level.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Paul Mackerras <paulus@samba.org>
2008-06-02 14:56:35 -05:00
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
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
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
Josh Boyer
1daa194a87 [POWERPC] Fix 40x build
Remove inclusion of __res on 40x.  We don't need it in arch/powerpc

Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
2007-08-20 07:29:36 -05:00
Josh Boyer
4d922c8dc3 [POWERPC] 40x MMU
Add MMU definitions for 40x platforms.  Also fixes two warnings in 40x_mmu.c.

Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
2007-08-20 07:28:48 -05:00
Josh Boyer
15f6527e8e [POWERPC] Rename 4xx paths to 40x
4xx is a bit of a misnomer for certain things, as they really apply to PowerPC
40x only.  Rename some of the files to clean this up.

Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
2007-08-20 07:27:07 -05:00