A number of small optimisations to FPU handling, in particular:
- move the task USEDFPU flag from the thread_info flags field (which
is accessed asynchronously to the thread) to a new status field,
which is only accessed by the thread itself. This allows locking to
be removed in most cases, or can be reduced to a preempt_lock().
This mimics the i386 behaviour.
- move the modification of regs->sr and thread_info->status flags out
of save_fpu() to __unlazy_fpu(). This gives the compiler a better
chance to optimise things, as well as making save_fpu() symmetrical
with restore_fpu() and init_fpu().
- implement prepare_to_copy(), so that when creating a thread, we can
unlazy the FPU prior to copying the thread data structures.
Also make sure that the FPU is disabled while in the kernel, in
particular while booting, and for newly created kernel threads,
In a very artificial benchmark, the execution time for 2500000
context switches was reduced from 50 to 45 seconds.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The previous implementation of clear_user_highpage and copy_user_highpage
checked to see if there was a D-cache aliasing issue between the user
and kernel mappings of a page, but if there was they always did a
flush with writeback on the dirtied kernel alias.
However as we now have the ability to map a page into kernel space
with the same cache colour as the user mapping, there is no need to
write back this data.
Currently we also invalidate the kernel alias as a precaution, however
I'm not sure if this is actually required.
Also correct the definition of FIX_CMAP_END so that the mappings created
by kmap_coherent() are actually at the correct colour.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Optimised version of memset for the SH4 which uses movca.l.
Signed-off-by: Stuart Menefy <stuart.menefy@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
sh port of the sLeAZY-fpu feature currently implemented for some architectures
such us i386.
Right now the SH kernel has a 100% lazy fpu behaviour.
This is of course great for applications that have very sporadic or no FPU use.
However for very frequent FPU users... you take an extra trap every context
switch.
The patch below adds a simple heuristic to this code: after 5 consecutive
context switches of FPU use, the lazy behavior is disabled and the context
gets restored every context switch.
After 256 switches, this is reset and the 100% lazy behavior is returned.
Tests with LMbench showed no regression.
I saw a little improvement due to the prefetching (~2%).
The tests below also show that, with this sLeazy patch, indeed,
the number of FPU exceptions is reduced.
To test this. I hacked the lat_ctx LMBench to use the FPU a little more.
sLeasy implementation
===========================================
switch_to calls | 79326
sleasy calls | 42577
do_fpu_state_restore calls| 59232
restore_fpu calls | 59032
Exceptions: 0x800 (FPU disabled ): 16604
100% Leazy (default implementation)
===========================================
switch_to calls | 79690
do_fpu_state_restore calls | 53299
restore_fpu calls | 53101
Exceptions: 0x800 (FPU disabled ): 53273
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 typename member of struct irq_chip was kept for migration purposes
and is obsolete since more than 2 years. Fix up the leftovers.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-sh@vger.kernel.org
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This is a static symbol, so the export is wholly superfluous. Recent
kbuild updates flagged this as an error, resulting in build failure,
so this tidies that up.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This gets the build fixed up for the sh64 cache enabled case.
Disabling still needs further abstraction for independent I/D-cache
disabling.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
sh64 doesn't use GENERIC_BUG, which presently causes the handle_BUG()
code to blow up. Fix up the dependencies and get it all building again.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This fixes up the build and behaviour for various configurations. Namely
the CONFIG_32BIT cases where legacy mappings do not exist, as well as the
sh64 build.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Presently the PMB options were limited to a number of CPUs they were
tested with, but it is generally available on all SH-4A CPUs, so just
drop the subtype conditionals.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
SPIN_LOCK_UNLOCKED is deprecated. Use __SPIN_LOCK_UNLOCKED instead.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-sh@vger.kernel.org
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The icache may also contain aliases so we must account for them just
like we do when manipulating the dcache. We usually get away with
aliases in the icache because the instructions that are read from memory
are read-only, i.e. they never change. However, the place where this
bites us is when the code has been modified.
Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The dwarf unwinder presently attempts to provide a sane PC value if none
is provided, however the logic is broken and cases where a previous valid
dwarf frame exists along with a bogus PC value can still proceed. This
fixes up the test and prevents the unwinder from blowing up.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This reduces the 'count' size in the common support structure to 32-bits
so that it matches up with what oprofile is expecting. The SH7750 code
was using a nasty oprofilefs hack to expose the 48-bit counter, although
no other implementations were. Now that the offending driver has been
killed off, it's possible to restore some semblance of sanity.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This kills off the old SH7750 oprofile driver, preferring perf instead.
As this driver has a number of bugs that no one seems to have noticed,
it's safe to kill this off now rather than providing an extended
transition period.
The old oprofile framework is still kept in place for now, primarily to
give out-of-tree drivers a chance to transition off. But this too will be
killed off in short order.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This implements preliminary support for perf callchains (at the moment
only the kernel side is implemented). The actual implementation itself is
just a simple wrapper around the unwinder API, which allows for callchain
generation with or without the dwarf unwinder.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Wanted by the SPU2 UIO driver, which really ought to be handling this
itself. Default enable it for now, until the driver gets a bit more
intelligent.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
'config' can be unintialized, and although it's not really an error, it
still manages to trigger the -Werror with certain toolchains. Initialize
it early to shut up gcc.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The indexes are signed, make sure they are not negative
when we read array elements.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Add sh7724 code to save and restore RWDT state during
R-standby. Without this patch the watchdog will generate
a reset shortly after resuming from R-standby.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This gets rid of the arbitrary set of vectors used by the SE7722 FPGA
interrupt controller and witches over to a completely dynamic set.
No assumptions regarding a contiguous range are made, and the platform
resources themselves need to be filled in lazily.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Different CPUs will have different starting vectors, with varying
amounts of reserved or unusable vector space prior to the first slot.
This introduces a legacy vector reservation system that inserts itself in
between the CPU vector map registration and the platform specific IRQ
setup. This works fine in practice as the only new vectors that boards
need to establish on their own should be dynamically allocated rather
than arbitrarily assigned. As a plus, this also makes all of the
converted platforms sparseirq ready.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Get rid of the unused WP signal for SDHI0 on KFR2R09.
This because yc304 on KFR2R09 is a Micro SD slot which
does not implement the WP signal.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Update the SDHI platform data for the AP325RXA board
to include support for the CN7 Micro SD Card slot.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Add R-standby specific bits to the SuperH Mobile sleep code.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Use RSMEM instead of ILMEM for sleep mode code storage on SH7724.
This allows us to use R-standby mode on SH7724.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Add MMU and cache handling functionality to the SuperH Mobile
sleep code. The MMU and cache registers are saved and restored.
The MMU is disabled and the cache is flushed and disabled before
entering sleep modes if the SUSP_SH_MMU flag is set. This flag
should be set in the case of R-standby and most likely for future
U-standby support as well.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Add code to keep track of supported sleep modes. This to
only export cpuidle modes that are backed by board support
code. Also, do not allow suspend-to-ram if sdram board code
is missing.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Rework the SuperH Mobile sleep code from including
board specific code to allowing each board to provide
pre/post code snippets. These snippets should contain
sdram management code to enter and leave self-refresh.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Move the AP325RXA board code from a single board file
to a separate directory. This to make it easy to add
support for sdram sleep mode code.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Add code to allow boards registering self-contained
functions for going to/from self-refresh. At this
point the board code is unused. When all supported
boards have been converted then the new sleep code
will make use of these functions.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Make use of the recently added notifier chains for sh7724
r-standby register save/restore handling. At this point
only the BSC and INTC are handled.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch adds atomic notifier chains for pre/post
sleep events. Useful for cpu code and boards that
need to save and restore register state before and
after entering a sleep mode.
Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The variable 'phys' already contains the physical address to flush. It
is not a virtual address and should not be passed to virt_to_phys().
Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
