This fixes up the kmap_coherent/kunmap_coherent() interface for recent
changes both in the page fault path and the shared cache flushers, as
well as adding in some optimizations.
One of the key things to note here is that the TLB flush itself is
deferred until the unmap, and the call in to update_mmu_cache() itself
goes away, relying on the regular page fault path to handle the lazy
dcache writeback if necessary.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This board doesn't use trapped I/O for anything, so just kill off the
select. This was causing problems in the unhandled page fault die path.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This builds on top of the previous reversion and implements a special
on_each_cpu() variant that simple disables preemption across the call
while leaving the interrupt state to the function itself. There were some
unintended consequences with IRQ disabling in some of these paths on UP
that ran in to a deadlock scenario with IRQs being missed.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This reverts commit 64a6d72213.
Unfortunately we can't use on_each_cpu() for all of the cache ops, as
some of them only require preempt disabling. This seems to be the same
issue that impacts the mips r4k caches, where this code was based on.
This fixes up a deadlock that showed up in some IRQ context cases.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The kgdb stub has traditionally tied in to the NMI slot, and manually
handled debounce. Now that we have a generic way to do this instead, all
of the stub-specific debounce silliness can be killed off.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This implements support for NMI debugging that was shamelessly copied
from the avr32 port. A bit of special magic is needed in the interrupt
exception path given that the NMI exception handler is stubbed in to the
regular exception handling table despite being reported in INTEVT. So we
mangle the lookup and kick off an EXPEVT-style exception dispatch from
the INTEVT path for exceptions that do_IRQ() has no chance of handling.
As a result, we also drop the evt2irq() conversion from the do_IRQ() path
and just do it in assembly.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This adopts the special-cased 2-way write-through dcache flusher for
N-ways and moves it in to the generic path. Assignment is done at runtime
via the check for the CCR_CACHE_WT bit in the same path as the per-way
writeback flushers.
Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Some unaligned accesses are completely expected. For example, the
trapped_io code uses the unaligned access fixup code path so there's no
need to warn about having to fixup the unaligned access.
Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This is supposed to be the equivalent of __NR_syscalls, not
__NR_syscalls -1. The x86 code this was based on had simply fallen
out of sync at the time this was implemented. Fix it up now.
As a result, tracing of __NR_perf_counter_open works as advertised.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch changes the way in which "multi-evt" interrups are handled.
The intc_evt2irq_table and related intc_evt2irq() have been removed and
the "redirecting" handler is installed for the coupled interrupts.
Thanks to that the do_IRQ() function don't have to use another level
of indirection for all the interrupts...
Signed-off-by: Pawel Moll <pawel.moll@st.com>
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
sys_cacheflush should return with EINVAL if the cache parameter is not
one of ICACHE, DCACHE or BCACHE.
So, we need to include 0 in the first check.
It also adds the three definitions above as wrapper of the existent macros.
PS: ltp cacheflush01 test now passes.
Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Change the method used to flush the cache in write-through mode to
avoid corrupted data being written back to memory.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Allow peripherals before the start of RAM to be remapped.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
It is possible for the CPU to re-enable it's interrupt block bit
before the write to the interrupt controller has actually masked out
the external interupt at the controller. We get around this by
reading back from the interrupt controller which will ensure the
write has happened.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Adds a system call to allow user code to flush code from the cache.
You can use instructions for the data side, but the iside can
only be done by a flush ROM which really only works with a direct
mapped cache. The later SH4's have 2 way Iside, so this call allows
a portable way to flush the cache.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This is a pure documentation, to try to explain why the cache flushing code
for the SH4 is implemented the way it is.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Optimise memcpy_to/fromio. This is used extensivly by MTD, so is a
worthwhile performance gain. The main savings come from not repeatedly
calling readl/writel, and doing word instead of byte at a time
transfers. Also using "movca.l" on SH4 gives a small performance win.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
After performing the port2addr conversion, and checking that the data is
correctly aligned, simply call __raw_readsX/writesX. These have already been
optimised.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Reading from the ROM is not a good idea as it could disturb some
flash operation that it is in progress.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The SH instruction set has several instructions which accept an 8 bit
immediate operand. For logical instructions this operand is zero extended,
for arithmetic instructions the operand is sign extended. After adding an
option to the assembler to check this, it was found that several pieces
of assembly code were assuming this behaviour, and in one case
getting it wrong.
So this patch explicitly sign extends any immediate operands, which makes
it obvious what is happening, and fixes the one case which got it wrong.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
So far kernel command line arguments could be passed in by a bootloader
or defined as CONFIG_CMDLINE, which completely overwriting the first one.
This change allows a developer to declare selected kernel parameters in
a kernel configuration (eg. project-specific defconfig), retaining
possibility of passing others by a bootloader.
The obvious examples of the first type are MTD partition or
bigphysarea-like region definitions, while "debug" option or network
configuration should be given by a bootloader or a JTAG boot script.
Signed-off-by: Pawel Moll <pawel.moll@st.com>
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patches will trigger a reboot using the watchdog
timer instead of double fault. Unlike the previous
method, this one actually works in 32 bit mode.
Reset should also be cleaner.
Signed-off-by: Jon Frosdick <jon.frosdick@st.com>
Signed-off-by: Carl Shaw <carl.shaw@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Save the VBR allowing GDB to dump full registers set but do not reload it
as soon as the kgdb_handle_exception is invoked.
Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The synopsys PCI cell used in the later STMicro chips requires code to
be run in order to do IO cycles, rather than just memory mapping the IO
space. Rather than extending the existing SH infrastructure to allow
this, use the GENERIC_IOMAP implmentation to save re-inventing the
wheel.
This set of changes allows the SH to be built with GENERIC_IOMAP
enabled, it just ifdef's out the functions provided by the GENERIC_IOMAP
implementation, and provides a few required missing functions.
Signed-off-by: David McKay <david.mckay@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
GCC does not issue unwind information for function epilogues.
Unfortunately we can catch a signal during an epilogue. The signal
handler writes the current context and signal return code onto the stack
overwriting previous contents. During unwinding, libgcc can try to
restore registers from the stack and restores corrupted ones. This can
lead to segmentation, misaligned access and sigbus faults.
For example, consider the following code:
mov.l r12,@-r15
mov.l r14,@-r15
sts.l pr,@-r15
mov r15,r14
<do stuff>
mov r14, r15
lds.l @r15+, pr
<<< SIGNAL HERE
mov.l @r15+, r14
mov.l @r15+, r12
rts
Unwind is aware that pr was pushed to stack in prolog, so tries to
restore it. Unfortunately it restores the last word of the signal
handler code placed on the stack by the kernel.
This patch tries to avoid the problem by adding a guard region on the
stack between where the function pushes data and where the signal handler
pushes its return code. We probably don't see this problem often because
exception handling unwinding in an epilogue only occurs due to a pthread
cancel signal. Also the kernel signal stack handler alignment of 8 bytes
could hide the occurance of this problem sometimes as the stack may not
be trampled at a particular required word.
This is not guaranteed to always work. It relies on a frame pointer
existing for the function (so it can get the correct sp value) which is
not always the case for the SH4.
Modifications will also be made to libgcc for the case where there is no
fp.
Signed-off-by: Carl Shaw <carl.shaw@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch fixes a few problems with the existing code in do_address_error().
a) the variable used to printk()d the offending instruction wasn't
initialized correctly. This is a fix to bug 5727
b) behaviour for CONFIG_CPU_SH2A wasn't correct
c) the 'ignore address error' behaviour didn't update the PC, causing an
infinite loop.
Signed-off-by: Andre Draszik <andre.draszik@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch brings the SH4 misaligned trap handler in line with what
happens on ARM:
Add a /proc/cpu/alignment which can be read from to get alignment
trap statistics and written to to influence the behaviour of the
alignment trap handling. The value to write is a bitfield, which
has the following meaning: 1 warn, 2 fixup, 4 signal
In addition, we add a /proc/cpu/kernel_alignment, to enable or
disable warnings in case of kernel code causing alignment errors.
Signed-off by: Andre Draszik <andre.draszik@st.com>
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch makes sure we see messages about unaligned access fixups
every now and then. Else especially userspace apps suffering from
bad programming won't ever be noticed...
Signed-off by: Andre Draszik <andre.draszik@st.com>
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The Runtime PM patch for UIO driver implements coarse grained
dynamic power management for UIO devices. With that patch in
place we can get rid of the static clock configuration. Which
in turn makes it possible for cpuidle to enter deeper sleep.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
With the Runtime PM driver changes in place, we must have
Runtime PM support in place. Otherwise there is no way to
enable clocks to the Runtime PM enabled hardware blocks.
This patch makes Runtime PM mandatory on SuperH Mobile.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The runtime PM for SH-Mobile code had platform_bus_notify() as __devinit,
which is rather bogus. Kill off the annotation, which subsequently
silences the section mismatch warnings.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch is V3 of the SuperH Mobile Runtime PM platform bus
implentation matching Rafael's Runtime PM v16.
The code gets invoked from the SuperH specific Runtime PM
platform bus functions that override the weak symbols for:
- platform_pm_runtime_suspend()
- platform_pm_runtime_resume()
- platform_pm_runtime_idle()
This Runtime PM implementation performs two levels of power
management. At the time of platform bus runtime suspend the
clock to the device is stopped instantly. Later on if all
devices within the power domain has their clocks stopped
then the device driver ->runtime_suspend() callbacks are
used to save hardware register state for each device.
Device driver ->runtime_suspend() calls are scheduled from
cpuidle context using platform_pm_runtime_suspend_idle().
When all devices have been fully suspended the processor
is allowed to enter deep sleep from cpuidle.
The runtime resume operation turns on clocks and also
restores registers if needed. It is worth noting that the
devices start in a suspended state and the device driver
is responsible for calling runtime resume before accessing
the actual hardware.
In this particular platform bus implementation runtime
resume is not allowed from interrupt context. Runtime
suspend is however allowed from interrupt context as
long as the synchronous functions are avoided.
[ updated for v17 -- PFM. ]
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Paul Mundt
Matt Fleming
Yoshihiro Shimoda
Kuninori Morimoto
Pawel Moll
Giuseppe Cavallaro
Stuart Menefy
Jon Frosdick
David McKay
Carl Shaw
Andre Draszik
Magnus Damm