Commit Graph

19 Commits

Author SHA1 Message Date
Alex Smith a7f4df4e21 MIPS: VDSO: Add implementations of gettimeofday() and clock_gettime()
Add user-mode implementations of gettimeofday() and clock_gettime() to
the VDSO. This is currently usable with 2 clocksources: the CP0 count
register, which is accessible to user-mode via RDHWR on R2 and later
cores, or the MIPS Global Interrupt Controller (GIC) timer, which
provides a "user-mode visible" section containing a mirror of its
counter registers. This section must be mapped into user memory, which
is done below the VDSO data page.

When a supported clocksource is not in use, the VDSO functions will
return -ENOSYS, which causes libc to fall back on the standard syscall
path.

When support for neither of these clocksources is compiled into the
kernel at all, the VDSO still provides clock_gettime(), as the coarse
realtime/monotonic clocks can still be implemented. However,
gettimeofday() is not provided in this case as nothing can be done
without a suitable clocksource. This causes the symbol lookup to fail
in libc and it will then always use the standard syscall path.

This patch includes a workaround for a bug in QEMU which results in
RDHWR on the CP0 count register always returning a constant (incorrect)
value. A fix for this has been submitted, and the workaround can be
removed after the fix has been in stable releases for a reasonable
amount of time.

A simple performance test which calls gettimeofday() 1000 times in a
loop and calculates the average execution time gives the following
results on a Malta + I6400 (running at 20MHz):

 - Syscall:    ~31000 ns
 - VDSO (GIC): ~15000 ns
 - VDSO (CP0): ~9500 ns

[markos.chandras@imgtec.com:
- Minor code re-arrangements in order for mappings to be made
in the order they appear to the process' address space.
- Move do_{monotonic, realtime} outside of the MIPS_CLOCK_VSYSCALL ifdef
- Use gic_get_usm_range so we can do the GIC mapping in the
arch/mips/kernel/vdso instead of the GIC irqchip driver]

Signed-off-by: Alex Smith <alex.smith@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/11338/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-11-11 08:36:41 +01:00
Linus Torvalds 807249d3ad Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus
Pull MIPS updates from Ralf Baechle:
 "This is the main pull request for 4.3 for MIPS.  Here's the summary:

  Three fixes that didn't make 4.2-stable:

   - a -Os build might compile the kernel using the MIPS16 instruction
     set but the R2 optimized inline functions in <uapi/asm/swab.h> are
     implemented using 32-bit wide instructions which is invalid.

   - a build error in pgtable-bits.h for a particular kernel
     configuration.

   - accessing registers of the CM GCR might have been compiled to use
     64 bit accesses but these registers are onl 32 bit wide.

  And also a few new bits:

   - move the ATH79 GPIO driver to drivers/gpio

   - the definition of IRQCHIP_DECLARE has moved to linux/irqchip.h,
     change ATH79 accordingly.

   - fix definition of pgprot_writecombine

   - add an implementation of dma_map_ops.mmap

   - fix alignment of quiet build output for vmlinuz link

   - BCM47xx: Use kmemdup rather than duplicating its implementation

   - Netlogic: Fix 0x0x prefixes of constants.

   - merge Bjorn Helgaas' series to remove most of the weak keywords
     from function declarations.

   - CP0 and CP1 registers are best considered treated as unsigned
     values to avoid large values from becoming negative values.

   - improve support for the MIPS GIC timer.

   - enable common clock framework for Malta and SEAD3.

   - a number of improvments and fixes to dump_tlb().

   - document the MIPS TLB dump functionality in Magic SysRq.

   - Cavium Octeon CN68XX improvments.

   - NetLogic improvments.

   - irq: Use access helper irq_data_get_affinity_mask.

   - handle MSA unaligned accesses.

   - a number of R6-related math-emu fixes.

   - support for I6400.

   - improvments to MSA support.

   - add uprobes support.

   - move from deprecated __initcall to arch_initcall.

   - remove finish_arch_switch().

   - IRQ cleanups by Thomas Gleixner.

   - migrate to new 'set-state' interface.

   - random small cleanups"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (148 commits)
  MIPS: UAPI: Fix unrecognized opcode WSBH/DSBH/DSHD when using MIPS16.
  MIPS: Fix alignment of quiet build output for vmlinuz link
  MIPS: math-emu: Remove unused handle_dsemul function declaration
  MIPS: math-emu: Add support for the MIPS R6 MAX{, A} FPU instruction
  MIPS: math-emu: Add support for the MIPS R6 MIN{, A} FPU instruction
  MIPS: math-emu: Add support for the MIPS R6 CLASS FPU instruction
  MIPS: math-emu: Add support for the MIPS R6 RINT FPU instruction
  MIPS: math-emu: Add support for the MIPS R6 MSUBF FPU instruction
  MIPS: math-emu: Add support for the MIPS R6 MADDF FPU instruction
  MIPS: math-emu: Add support for the MIPS R6 SELNEZ FPU instruction
  MIPS: math-emu: Add support for the MIPS R6 SELEQZ FPU instruction
  MIPS: math-emu: Add support for the CMP.condn.fmt R6 instruction
  MIPS: inst.h: Add new MIPS R6 FPU opcodes
  MIPS: Octeon: Fix management port MII address on Kontron S1901
  MIPS: BCM47xx: Use kmemdup rather than duplicating its implementation
  STAGING: Octeon: Use common helpers for determining interface and port
  MIPS: Octeon: Support interfaces 4 and 5
  MIPS: Octeon: Set up 1:1 mapping between CN68XX PKO queues and ports
  MIPS: Octeon: Initialize CN68XX PKO
  STAGING: Octeon: Support CN68XX style WQE
  ...
2015-09-03 16:55:55 -07:00
Ezequiel Garcia fc6a6772f8 CLOCKSOURCE: mips-gic: Update clockevent frequency on clock rate changes
This commit introduces the clockevent frequency update, using
a clock notifier. It will be used to support CPUFreq on platforms
using MIPS GIC based clockevents.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: James Hartley <James.Hartley@imgtec.com>
Cc: Govindraj Raja <Govindraj.Raja@imgtec.com>
Cc: Damien Horsley <Damien.Horsley@imgtec.com>
Cc: James Hogan <James.Hogan@imgtec.com>
Cc: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Patchwork: https://patchwork.linux-mips.org/patch/10782/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-09-03 12:08:07 +02:00
Ezequiel Garcia 67d4e669c1 CLOCKSOURCE: mips-gic: Split clocksource and clockevent initialization
This is preparation work for the introduction of clockevent frequency
update with a clock notifier. This is only possible when the device
is passed a clk struct, so let's split the legacy and devicetree
initialization.

Reviewed-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: James Hartley <James.Hartley@imgtec.com>
Cc: Govindraj Raja <Govindraj.Raja@imgtec.com>
Cc: Damien Horsley <Damien.Horsley@imgtec.com>
Cc: James Hogan <James.Hogan@imgtec.com>
Cc: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Patchwork: https://patchwork.linux-mips.org/patch/10781/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-09-03 12:08:06 +02:00
Ezequiel Garcia f95ac8558b CLOCKSOURCE: mips-gic: Add missing error returns checks
This commit adds the required checks on the functions that return
an error. Some of them are not critical, so only a warning is
printed.

Signed-off-by: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Reviewed-by: Andrew Bresticker <abrestic@chromium.org>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: James Hartley <James.Hartley@imgtec.com>
Cc: Govindraj Raja <Govindraj.Raja@imgtec.com>
Cc: Damien Horsley <Damien.Horsley@imgtec.com>
Cc: James Hogan <James.Hogan@imgtec.com>
Cc: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Patchwork: https://patchwork.linux-mips.org/patch/10780/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-09-03 12:08:06 +02:00
Ezequiel Garcia eb811c73b6 CLOCKSOURCE: mips-gic: Enable the clock before using it
For the clock to be used (e.g. get its rate through clk_get_rate)
it should be prepared and enabled first.

Also, while the clock is enabled the driver must hold a reference to it,
so let's remove the call to clk_put.

Reviewed-by: Andrew Bresticker <abrestic@chromium.org>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: James Hartley <James.Hartley@imgtec.com>
Cc: Govindraj Raja <Govindraj.Raja@imgtec.com>
Cc: Damien Horsley <Damien.Horsley@imgtec.com>
Cc: James Hogan <James.Hogan@imgtec.com>
Cc: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Patchwork: https://patchwork.linux-mips.org/patch/10779/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-09-03 12:08:05 +02:00
Viresh Kumar d47409347e clockevents/drivers/mips-gic: Migrate to new 'set-state' interface
Migrate mips-gic driver to the new 'set-state' interface provided by
clockevents core, the earlier 'set-mode' interface is marked obsolete
now.

This also enables us to implement callbacks for new states of clockevent
devices, for example: ONESHOT_STOPPED.

We weren't doing anything in the ->set_mode() callback. So, this patch
doesn't provide any set-state callbacks.

Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2015-08-10 11:40:32 +02:00
Andrew Bresticker 5b4e845393 CLOCKSOURCE: mips-gic: Allow GIC clock to be specified in device-tree
As an alternative to the "clock-frequency" property, allow the GIC
timer operating clock to be specified in the device-tree instead.
This is useful on systems which use common clock or where the GIC
is not fixed to a particular frequency and is instead, for example,
derived from the CPU clock.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: Kumar Gala <galak@codeaurora.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: devicetree@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/9309/
2015-04-01 17:22:11 +02:00
Markos Chandras 7d9cd1f518 CLOCKSOURCE: mips-gic-timer: Ensure GIC counter is running
Start the GIC counter after configuring the clocksource since there
are no guarantees the counter will be running after a CPU reset.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/9595/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2015-03-31 12:04:13 +02:00
Andrew Bresticker e12aa828ff clocksource: mips-gic: Add device-tree support
Parse the GIC timer frequency and interrupt from the device-tree.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: Kumar Gala <galak@codeaurora.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: John Crispin <blogic@openwrt.org>
Cc: David Daney <ddaney.cavm@gmail.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8421/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:30 +01:00
Andrew Bresticker a45da56598 clocksource: mips-gic: Bump up rating of GIC timer
Bump up the rating of the GIC timer so that it gets prioritized
over the CP0 timer.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8141/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:16 +01:00
Andrew Bresticker b695d8e6ad clocksource: mips-gic: Use clockevents_config_and_register
Use clockevents_config_and_register to setup the clock_event_device
based on frequency and min/max ticks instead of doing it ourselves.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8140/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:16 +01:00
Andrew Bresticker e4752dbbc3 clocksource: mips-gic: Use CPU notifiers to setup the timer
Instead of requiring an explicit call to gic_clockevent_init in the SMP
startup path, use CPU notifiers to register and enable the GIC timer on
CPU startup.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8139/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:16 +01:00
Andrew Bresticker f7ea3060b6 clocksource: mips-gic: Use percpu_dev_id
Since the GIC timer IRQ is a percpu IRQ, we can use percpu_dev_id
to pass the IRQ handler the correct clock_event_device.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8138/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:15 +01:00
Andrew Bresticker 001f5fe72c clocksource: mips-gic: Remove gic_event_handler
Remove gic_event_handler since it is completely unnecessary.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8136/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:15 +01:00
Andrew Bresticker b085451453 clocksource: mips-gic: Move gic_frequency to clocksource driver
There's no reason for gic_frequency to be global any more and it
certainly doesn't belong in the GIC irqchip driver, so move it to
the GIC clocksource driver.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8137/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:15 +01:00
Andrew Bresticker 5fee56e0dd clocksource: mips-gic: Staticize local symbols
There are a number of variables and functions which are unnecessarily
global.  Mark them static.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8135/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:15 +01:00
Andrew Bresticker a331ce63c8 clocksource: mips-gic: Combine with GIC clockevent driver
Combine the GIC clocksource driver with the GIC clockevent driver from
arch/mips/kernel/cevt-gic.c and remove the clockevent driver's separate
Kconfig symbol.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8132/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:15 +01:00
Andrew Bresticker fa5635a277 MIPS: Move GIC clocksource driver to drivers/clocksource/
Move the GIC clocksource driver to drivers/clocksource/mips-gic-timer.c.

Signed-off-by: Andrew Bresticker <abrestic@chromium.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Qais Yousef <qais.yousef@imgtec.com>
Cc: John Crispin <blogic@openwrt.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/8133/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
2014-11-24 07:45:14 +01:00