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2009-08-24sh: Add sys_cacheflush() call for SH CPUs.Stuart Menefy
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>
2009-08-24sh: Optimise memcpy_to/fromio for SH4Stuart Menefy
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>
2009-08-24sh: generic_in/outs{bwl} optimizations.Stuart Menefy
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>
2009-08-24sh: Remove implicit sign extension from assembler immediatesStuart Menefy
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>
2009-08-24sh: Allow for kernel command line concatenation.Pawel Moll
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>
2009-08-24sh: Use internal watchdog timer to perform resetJon Frosdick
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>
2009-08-24sh: kgdb: do not reload VBR while handling debugger breackpointGiuseppe Cavallaro
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>
2009-08-24sh: Allow use of GENERIC_IOMAPDavid McKay
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>
2009-08-24sh: Improve unwind info for signalsCarl Shaw
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>
2009-08-24sh: cleanup of do_address_error()Andre Draszik
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>
2009-08-24sh: Allow user control over misaligned fixup handlingAndre Draszik
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>
2009-08-24sh: ratelimit unaligned fixupsAndre Draszik
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>
2009-08-23Merge branches 'sh/hwblk' and 'sh/pm-runtime'Paul Mundt
2009-08-23sh: drop static UIO clocks for sh7722, sh7723 and sh7724Magnus Damm
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>
2009-08-23sh: Fix section mismatch in platform bus notifier.Paul Mundt
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>
2009-08-23sh: Runtime PM for SuperH Mobile platform bus devicesMagnus Damm
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>
2009-08-22sh: unwinder: cacheline align slab cache objects.Paul Mundt
The CIE and FDE structs are big enough and accessed regularly enough in certain configurations to make cacheline alignment useful. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-22Merge branch 'sh/dwarf-unwinder'Paul Mundt
Conflicts: arch/sh/kernel/cpu/sh3/entry.S
2009-08-22sh: unwinder: Use a special bug flag for unwinder traps.Paul Mundt
This simplifies the unwinder trap handling, dropping the use of the special trapa vector and simply piggybacking on top of the BUG support. A new BUGFLAG_UNWINDER is added for flagging the unwinder fault, before continuing on with regular BUG dispatch. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-22Merge branch 'sh/dwarf-unwinder' of git://github.com/mfleming/linux-2.6 into ↵Paul Mundt
sh/dwarf-unwinder
2009-08-22sh: Export unwind_stack() to satisfy modular oprofile.Paul Mundt
If the oprofile code is built as a module, unwind_stack() as used by the oprofile backtrace code is not available, causing build breakage. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-21sh: Handle the DWARF op, DW_CFA_undefinedMatt Fleming
Allow a DWARF register to have an undefined value. When applied to the DWARF return address register this lets lets us label a function as having no direct caller, e.g. kernel_thread_helper(). Signed-off-by: Matt Fleming <matt@console-pimps.org>
2009-08-21sh: Fix bug calculating the end of the FDE instructionsMatt Fleming
The 'end' member of struct dwarf_fde denotes one byte past the end of the CFA instruction stream for an FDE. The value of 'end' was being calcualted incorrectly, it was being set too high. This resulted in dwarf_cfa_execute_insns() interpreting data past the end of valid instructions, thus causing all sorts of weird crashes. Signed-off-by: Matt Fleming <matt@console-pimps.org>
2009-08-21sh: Setup the frame pointer in handle_interruptMatt Fleming
When CONFIG_DWARF_UNWINDER is enabled setup r14 in handle_interrupt, so that we can figure out what function was running when we were interrupted. Signed-off-by: Matt Fleming <matt@console-pimps.org>
2009-08-21sh: unwinder: Introduce UNWINDER_BUG() and UNWINDER_BUG_ON()Matt Fleming
We can't assume that if we execute the unwinder code and the unwinder was already running that it has faulted. Clearly two kernel threads can invoke the unwinder at the same time and may be running simultaneously. The previous approach used BUG() and BUG_ON() in the unwinder code to detect whether the unwinder was incapable of unwinding the stack, and that the next available unwinder should be used instead. A better approach is to explicitly invoke a trap handler to switch unwinders when the current unwinder cannot continue. Signed-off-by: Matt Fleming <matt@console-pimps.org>
2009-08-21sh: unwinder: Set the flags for DW_CFA_val_offset ops as DWARF_VAL_OFFSETMatt Fleming
The handling of DW_CFA_val_offset ops was incorrectly using the DWARF_REG_OFFSET flag but the register's value cannot be calculated using the DWARF_REG_OFFSET method. Create a new flag to indicate that a different method must be used to calculate the register's value even though there is no implementation for DWARF_VAL_OFFSET yet; it's mainly just a place holder. Signed-off-by: Matt Fleming <matt@console-pimps.org>
2009-08-21sh: unwinder: Fix memory leak and create our own kmem cacheMatt Fleming
Plug a memory leak in dwarf_unwinder_dump() where we didn't free the memory that we had previously allocated for the DWARF frames and DWARF registers. Now is also a opportune time to implement our own mempool and kmem cache. It's a good idea to have a certain number of frame and register objects in reserve at all times, so that we are guaranteed to have our allocation satisfied even when memory is scarce. Since we have pools to allocate from we can implement the registers for each frame as a linked list as opposed to a sparsely populated array. Whilst it's true that the lookup time for a linked list is larger than for arrays, there's only usually a maximum of 8 registers per frame. So the overhead isn't that much of a concern. Signed-off-by: Matt Fleming <matt@console-pimps.org>
2009-08-21sh: Add initial support for SH7757 CPU subtypeYoshihiro Shimoda
Signed-off-by: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-20sh: Fix up the CONFIG_FTRACE_SYSCALLS=n build.Paul Mundt
-tip can't be bothered keeping interfaces stable long enough for anyone to use them without having their builds broken without notification, so just ifdef around the problematic symbols until the new interfaces become available upstream. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-19sh: Fix up clockevents broadcasting.Paul Mundt
This fixes up the clockevents broadcasting code as detailed in commit ee348d5a1d810bc9958cabb7c27302aab235d36e ("[ARM] realview: fix broadcast tick support"). This saves us from having to do strange ordering things with the broadcast clockevent device, relying on the rating instead. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-19Merge branch 'master' into sh/cachetlbPaul Mundt
Conflicts: arch/sh/kernel/Makefile_64
2009-08-18sh: clkfwk: Support additional IFC divisor on SH7724.Kuninori Morimoto
This patch updates the FRQCRA.IFC divisor values for SH7724. Despite not being initially documented, the / 3 mode is also support for the IFC division. Signed-off-by: Kuninori Morimoto <morimoto.kuninori@renesas.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-18sh: Add a few missing irqflags tracing markers.Matt Fleming
save_regs contains an SR modification without an irqflags annotation, which resulted in a missing TRACE_IRQS_OFF in the interrupt exception path on SH-3/SH4. I've also moved the TRACE_IRQS_OFF/ON annotation when returning from the interrupt to just before we call __restore_all. This seems like the most logical place to put this because the annotation is for when we restore the SR register so we should delay the annotation until as last as possible. We were also missing a TRACE_IRQS_OFF in resume_kernel when CONFIG_PREEMPT is enabled. The end result is that this fixes up the lockdep engine debugging support with CONFIG_PREEMPT enabled on all SH-3/4 parts. Signed-off-by: Matt Fleming <matt@console-pimps.org> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-18sh: SuperH Mobile Software Standby support for cpuidleMagnus Damm
This patch adds "SuperH Mobile Standby Mode [SF]" to the list of cpuidle sleep modes. If the software latency requirements from cpuidle are met together with fulfilled hardware requirements then deep sleep modes can be entered. Tested on sh7722 and sh7724 with "Sleep Mode", "Sleep Mode + SF" and "Software Standby Mode + SF" together with a multimedia work load and flood ping without packet drop. Signed-off-by: Magnus Damm <damm@igel.co.jp> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-18sh: rework SuperH Mobile sleep code exception handlingMagnus Damm
This patch updates the exception handling in the sleep code for SuperH Mobile. With the patch applied the sleep code always rewrites the VBR and resumes from the exception vector, re-initializes hardware and jumps straight to the original interrupt vector. Tested on sh7722 and sh7724 with "Sleep Mode", "Sleep Mode + SF" and "Software Standby Mode + SF" with CONFIG_SUSPEND. Signed-off-by: Magnus Damm <damm@igel.co.jp> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-17sh: unwinder: Move initialization to early_initcall() and tidy up locking.Paul Mundt
This moves the initialization over to an early_initcall(). This fixes up some lockdep interaction issues. At the same time, kill off some superfluous locking in the init path. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-16sh: Add support for DWARF GNU extensionsMatt Fleming
Also, remove the "fix" to DW_CFA_def_cfa_register where we reset the frame's cfa_offset to 0. This action is incorrect when handling DW_CFA_def_cfa_register as the DWARF spec specifically states that the previous contents of cfa_offset should be used with the new register. The reason that I thought cfa_offset should be reset to 0 was because it was being assigned a bogus value prior to executing the DW_CFA_def_cfa_register op. It turns out that the bogus cfa_offset value came from interpreting .cfi_escape pseudo-ops (those used by the GNU extensions) as CFA_DW_def_cfa ops. Signed-off-by: Matt Fleming <matt@console-pimps.org>
2009-08-16sh: Try again at getting the initial return address for an unwindMatt Fleming
The previous hack for calculating the return address for the first frame we unwind (dwarf_unwinder_dump) didn't always work. The problem was that it assumed once it read the rule for calculating the return address, there would be no new rules for calculating it. This isn't true because the way in which the CFA is calculated can change as you progress through a function and the return address is figured out using the CFA. Therefore, the way to calculate the return address can change. So, instead of using some offset from the beginning of dwarf_unwind_stack which is just a flakey approach, and instead of executing instructions from the FDE until the return address is setup, we now figure out the pc in dwarf_unwind_stack() just before we call dwarf_cfa_execute_insns(). Signed-off-by: Matt Fleming <matt@console-pimps.org>
2009-08-16sh: Merge the _32/_64 variants of arch/sh/kernel/Makefile.Paul Mundt
This uses the BITS export as per x86 in order to allow the same Makefile to be used. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-16sh: Fix up the SH-5 build with caches enabled.Paul Mundt
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-16sh64: Build in support for generic stacktrace ops.Paul Mundt
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-15timekeeping: Increase granularity of read_persistent_clock()Martin Schwidefsky
The persistent clock of some architectures (e.g. s390) have a better granularity than seconds. To reduce the delta between the host clock and the guest clock in a virtualized system change the read_persistent_clock function to return a struct timespec. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Acked-by: John Stultz <johnstul@us.ibm.com> Cc: Daniel Walker <dwalker@fifo99.com> LKML-Reference: <20090814134811.013873340@de.ibm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-15sh: Kill off the unhandled pvr case in SH-4 CPU probing.Paul Mundt
This is superfluous, as the default CPU type and family are already established by the initial cpuinfo definition. Given that we are still able to probe for the CPU family even if we are not able to detect the subtype, it's preferable to let the probing code fill out what it can and leave the rest. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-15Merge branch 'master' into sh/hwblkPaul Mundt
2009-08-15Merge branch 'sh/stable-updates'Paul Mundt
2009-08-15sh: sh7724 ddr self-refresh changesMagnus Damm
This patch updates the SuperH Mobile sleep assembly code with support for DBSC memory controller found in the sh7724 processor. Without this fix the memory hooked up to the sh7724 processor will never enter self-refresh mode before suspending to ram. The effect of this is that the memory contents most likeley will be lost upon resume which may or may not be what you want. Signed-off-by: Magnus Damm <damm@igel.co.jp> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-15sh: Track the CPU family in sh_cpuinfo.Paul Mundt
This adds a family member to struct sh_cpuinfo, which allows us to fall back more on the probe routines to work out what sort of subtype we are running on. This will be used by the CPU cache initialization code in order to first do family-level initialization, followed by subtype-level optimizations. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-15sh: rework nommu for generic cache.c use.Paul Mundt
This does a bit of reorganizing for allowing nommu to use the new and generic cache.c, no functional changes. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-15sh: Set the cfa_offset to 0 if we see a DW_CFA_def_cfa_register opMatt Fleming
The way that the CFA is calculated can change as we progress through a function. If we see a DW_CFA_def_cfa_register op we need to reset the frame's cfa_offset value which may have been previously setup. Signed-off-by: Matt Fleming <matt@console-pimps.org> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-15sh: delay slot future proofing via EXPMASK on SH-4A parts.Paul Mundt
This implements EXPMASK initialization code for SH-4A parts, where it is possible to disable compat features that will go away in newer cores. Presently this includes disabling support for non-nop instructions in the rte delay slot, as well as a sleep instruction being placed in a delay slot (neither of which the kernel does any longer). As a result of this, any future offenders will have illegal slot exceptions generated for them. Associative writes for the memory-mapped cache array are still left enabled, until such a point that special cache operations for SH-4A are provided to move off of the current (and rather dated) SH-4 versions. Signed-off-by: Paul Mundt <lethal@linux-sh.org>