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2013-05-09Merge branch 'mti-next' of ↵Ralf Baechle
git://git.linux-mips.org/pub/scm/sjhill/linux-sjhill into mips-for-linux-next
2013-05-09MIPS: Add new GIC clockevent driver.Raghu Gandham
Add new clockevent driver that uses the counter present on the MIPS Global Interrupt Controller. Signed-off-by: Raghu Gandham <Raghu.Gandham@imgtec.com> Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
2013-05-09MIPS: Formatting clean-ups for clocksources.Steven J. Hill
Various whitespace and #ifdef removals for GIC and R4K clocksources. Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
2013-05-08KVM/MIPS32: KVM Guest kernel support.Sanjay Lal
Both Guest kernel and Guest Userspace execute in UM. The memory map is as follows: Guest User address space: 0x00000000 -> 0x40000000 Guest Kernel Unmapped: 0x40000000 -> 0x60000000 Guest Kernel Mapped: 0x60000000 -> 0x80000000 - Guest Usermode virtual memory is limited to 1GB. Signed-off-by: Sanjay Lal <sanjayl@kymasys.com> Cc: kvm@vger.kernel.org Cc: linux-mips@linux-mips.org Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2013-02-01MIPS: Whitespace cleanup.Ralf Baechle
Having received another series of whitespace patches I decided to do this once and for all rather than dealing with this kind of patches trickling in forever. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2012-09-13MIPS: Add EIC support for GIC.Steven J. Hill
Add support to use an external interrupt controller with the GIC. Signed-off-by: Steven J. Hill <sjhill@mips.com>
2011-12-07MIPS: irq: Remove IRQF_DISABLEDYong Zhang
Since commit [e58aa3d2: genirq: Run irq handlers with interrupts disabled], We run all interrupt handlers with interrupts disabled and we even check and yell when an interrupt handler returns with interrupts enabled (see commit [b738a50a: genirq: Warn when handler enables interrupts]). So now this flag is a NOOP and can be removed. [ralf@linux-mips.org: Fixed up conflicts in arch/mips/alchemy/common/dbdma.c, arch/mips/cavium-octeon/smp.c and arch/mips/kernel/perf_event.c.] Signed-off-by: Yong Zhang <yong.zhang0@gmail.com> To: linux-kernel@vger.kernel.org Cc: tglx@linutronix.de linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/2835/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2011-11-08MIPS: Kernel hangs occasionally during boot.Al Cooper
The Kernel hangs occasionally during boot after "Calibrating delay loop..". This is caused by the c0_compare_int_usable() routine in cevt-r4k.c returning false which causes the system to disable the timer and hang later. The false return happens because the routine is using a series of four calls to irq_disable_hazard() as a delay while it waits for the timer changes to propagate to the cp0 cause register. On newer MIPS cores, like the 74K, the series of irq_disable_hazard() calls turn into ehb instructions and can take as little as a few clock ticks for all 4 instructions. This is not enough of a delay, so the routine thinks the timer is not working. This fix uses up to a max number of cycle counter ticks for the delay and uses back_to_back_c0_hazard() instead of irq_disable_hazard() to handle the hazard condition between cp0 writes and cp0 reads. Signed-off-by: Al Cooper <alcooperx@gmail.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/2911/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2010-12-16MIPS: Fix CP0 COUNTER clockevent raceKevin Cernekee
Consider the following test case: write_c0_compare(read_c0_count()); Even if the counter doesn't increment during execution, this might not generate an interrupt until the counter wraps around. The CPU may perform the comparison each time CP0 COUNT increments, not when CP0 COMPARE is written. If mips_next_event() is called with a very small delta, and CP0 COUNT increments during the calculation of "cnt += delta", it is possible that CP0 COMPARE will be written with the current value of CP0 COUNT. If this is detected, the function should return -ETIME, to indicate that the interrupt might not have actually gotten scheduled. Signed-off-by: Kevin Cernekee <cernekee@gmail.com> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/1836/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2010-10-07MIPS: Add missing #inclusions of <linux/irq.h>David Howells
Add missing #inclusions of <linux/irq.h> to a whole bunch of files that should really include it. Note that this can replace #inclusions of <asm/irq.h>. This is required for the patch to sort out irqflags handling function naming to compile on MIPS. The problem is that these files require access to things like setup_irq() - which isn't available by #including <linux/interrupt.h> Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Ralf Baechle <ralf@linux-mips.org>
2010-08-05MIPS: Don't overflow cevt-r4k.c calculations at high clock rates.David Daney
The 'mult' element of struct clock_event_device must never be wider than 32-bits. If it were, it would get truncated when used by clockevent_delta2ns() when this calls do_div(). We can meet this requirement by using clockevent_set_clock() to set the MULT and SHIFT values. Signed-off-by: David Daney <ddaney@caviumnetworks.com> Cc: linux-mips@linux-mips.org Patchwork: https://patchwork.linux-mips.org/patch/1253/ Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2010-01-28MIPS: PowerTV: Fix support for timer interrupts with > 64 external IRQsDavid VomLehn
The MIPS processor is limited to 64 external interrupt sources. Using a greater number without IRQ sharing requires reading platform-specific registers. On such platforms, reading the IntCtl register to determine which interrupt corresponds to a timer interrupt will not work. On MIPSR2 systems there is a solution - the TI bit in the Cause register, specifically indicates that a timer interrupt has occured. This patch uses that bit to detect interrupts for MIPSR2 processors, which may be expected to work regardless of how the timer interrupt may be routed in the hardware. Signed-off-by: David VomLehn (dvomlehn@cisco.com) To: linux-mips@linux-mips.org Patchwork: http://patchwork.linux-mips.org/patch/804/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2009-11-02MIPS: Add IRQF_TIMER flag for timer interruptsWu Zhangjin
Along the lines of d6c585a4342a2ff627a29f9aea77c5ed4cd76023, add IRQF_TIMER flag for all timer interrupts This ensures that timer interrupts won't be disabled on suspend and not threaded for PREEMPT_RT. Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2009-06-24MIPS: Build fix - include <linux/smp.h> into all smp_processor_id() users.Ralf Baechle
Some of the were relying into smp.h being dragged in by another header which of course is fragile. <asm/cpu-info.h> uses smp_processor_id() only in macros and including smp.h there leads to an include loop, so don't change cpu-info.h. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2009-01-11MIPS: make cp0 counter clocksource/event usable as fallback.Manuel Lauss
The current mips clock build infrastructure lets a system only use either the MIPS cp0 counter or a SoC specific timer as a clocksource / clockevent device. This patch renames the core cp0 counter clocksource / clockevent functions from mips_* to r4k_* and updates the wrappers in asm-mips/time.h to call these renamed functions instead. Chips which can detect whether it is safe to use a chip-specific timer can now fall back on the cp0 counter if necessary and possible (e.g. Alchemy with a follow-on patch). Existing behaviour is not changed in any way. Signed-off-by: Manuel Lauss <mano@roarinelk.homelinux.net> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2008-12-13cpumask: convert struct clock_event_device to cpumask pointers.Rusty Russell
Impact: change calling convention of existing clock_event APIs struct clock_event_timer's cpumask field gets changed to take pointer, as does the ->broadcast function. Another single-patch change. For safety, we BUG_ON() in clockevents_register_device() if it's not set. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Cc: Ingo Molnar <mingo@elte.hu>
2008-10-03[MIPS] SMTC: Fix SMTC dyntick support.Kevin D. Kissell
Rework of SMTC support to make it work with the new clock event system, allowing "tickless" operation, and to make it compatible with the use of the "wait_irqoff" idle loop. The new clocking scheme means that the previously optional IPI instant replay mechanism is now required, and has been made more robust. Signed-off-by: Kevin D. Kissell <kevink@paralogos.com> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-11-26[MIPS] Handle R4000/R4400 mfc0 from count register.Ralf Baechle
The R4000 and R4400 have an errata where if the cp0 count register is read in the exact moment when it matches the compare register no interrupt will be generated. This bug may be triggered if the cp0 count register is being used as clocksource and the compare interrupt as clockevent. So a simple workaround is to avoid using the compare for both facilities on the affected CPUs. This is different from the workaround suggested in the old errata documents; at some opportunity probably the official version should be implemented and tested. Another thing to find out is which processor versions exactly are affected. I only have errata documents upto R4400 V3.0 available so for the moment the code treats all R4000 and R4400 as broken. This is potencially a problem for some machines that have no other decent clocksource available; this workaround will cause them to fall back to another clocksource, worst case the "jiffies" source.
2007-11-26[MIPS] time: Fix negated condition in cevt-r4k driver.Ralf Baechle
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-29[MIPS] time: Replace plat_timer_setup with modern APIs.Ralf Baechle
plat_timer_setup is no longer getting called. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-29[MIPS] time: Make c0_compare_int_usable fasterAtsushi Nemoto
Try increasingly longer time periods starting of at 0x10 cycles. This should be fast on hardware and work nicely with emulators. Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-29[MIPS] time: Fix cevt-r4k.c for 64-bit kernelAtsushi Nemoto
The expression "(long)(read_c0_count() - cnt)" can never be a negative value on 64-bit kernel. Cast to "int" before comparison. Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-29[MIPS] Add mips_hpt_frequency check to mips_clockevent_init().Yoichi Yuasa
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-22[MIPS] time: Make c0_compare_int_usable more bullet proofAtsushi Nemoto
Use write_c0_compare(read_c0_count()) to clear interrupt. Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-19[MIPS] SMTC: Build fix.Ralf Baechle
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2007-10-18[MIPS] time: Move R4000 clockevent device code to separate configurable fileRalf Baechle
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>