This change complements commits d0da7c002f7b2a93582187a9e3f73891a01d8ee4
[MIPS: DEC: Convert to new irq_chip functions] and
5359b938c0 [MIPS: DECstation I/O ASIC DMA
interrupt handling fix] and implements automatic handling of the two
classes of DMA interrupts the I/O ASIC implements, informational and
errors.
Informational DMA interrupts do not stop the transfer and use the
`handle_edge_irq' handler that clears the request right away so that
another request may be recorded while the previous is being handled.
DMA error interrupts stop the transfer and require a corrective action
before DMA can be reenabled. Therefore they use the `handle_fasteoi_irq'
handler that only clears the request on the way out. Because MIPS
processor interrupt inputs, one of which the I/O ASIC's interrupt
controller is cascaded to, are level-triggered it is recommended that
error DMA interrupt action handlers are registered with the IRQF_ONESHOT
flag set so that they are run with the interrupt line masked.
This change removes the export of clear_ioasic_dma_irq that now does not
have to be called by device drivers to clear interrupts explicitly
anymore. Originally these interrupts were cleared in the .end handler of
the `irq_chip' structure, before it was removed.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5874/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
o Move current_cpu_type() to a separate header file
o #ifdefing on supported CPU types lets modern GCC know that certain
code in callers may be discarded ideally turning current_cpu_type() into
a function returning a constant.
o Use current_cpu_type() rather than direct access to struct cpuinfo_mips.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5833/
This change complements commit d0da7c002f7b2a93582187a9e3f73891a01d8ee4
and brings clear_ioasic_irq back, renaming it to clear_ioasic_dma_irq at
the same time, to make I/O ASIC DMA interrupts functional.
Unlike ordinary I/O ASIC interrupts DMA interrupts need to be deasserted
by software by writing 0 to the respective bit in I/O ASIC's System
Interrupt Register (SIR), similarly to how CP0.Cause.IP0 and CP0.Cause.IP1
bits are handled in the CPU (the difference is SIR DMA interrupt bits are
R/W0C so there's no need for an RMW cycle). Otherwise the handler is
reentered over and over again.
The only current user is the DEC LANCE Ethernet driver and its extremely
uncommon DMA memory error handler that does not care when exactly the
interrupt is cleared. Anticipating the use of DMA interrupts by the Zilog
SCC driver this change however exports clear_ioasic_dma_irq for device
drivers to choose the right application-specific sequence to clear the
request explicitly rather than calling it implicitly in the .irq_eoi
handler of `struct irq_chip'. Previously these interrupts were cleared in
the .end handler of the said structure, before it was removed.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5826/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Not all I/O ASIC versions have the free-running counter implemented, an
early revision used in the 5000/1xx models aka 3MIN and 4MIN did not have
it. Therefore we cannot unconditionally use it as a clock source.
Fortunately if not implemented its register slot has a fixed value so it
is enough if we check for the value at the end of the calibration period
being the same as at the beginning.
This also means we need to look for another high-precision clock source on
the systems affected. The 5000/1xx can have an R4000SC processor
installed where the CP0 Count register can be used as a clock source.
Unfortunately all the R4k DECstations suffer from the missed timer
interrupt on CP0 Count reads erratum, so we cannot use the CP0 timer as a
clock source and a clock event both at a time. However we never need an
R4k clock event device because all DECstations have a DS1287A RTC chip
whose periodic interrupt can be used as a clock source.
This gives us the following four configuration possibilities for I/O ASIC
DECstations:
1. No I/O ASIC counter and no CP0 timer, e.g. R3k 5000/1xx (3MIN).
2. No I/O ASIC counter but the CP0 timer, i.e. R4k 5000/150 (4MIN).
3. The I/O ASIC counter but no CP0 timer, e.g. R3k 5000/240 (3MAX+).
4. The I/O ASIC counter and the CP0 timer, e.g. R4k 5000/260 (4MAX+).
For #1 and #2 this change stops the I/O ASIC free-running counter from
being installed as a clock source of a 0Hz frequency. For #2 it also
arranges for the CP0 timer to be used as a clock source rather than a
clock event device, because having an accurate wall clock is more
important than a high-precision interval timer. For #3 there is no
change. For #4 the change makes the I/O ASIC free-running counter
installed as a clock source so that the CP0 timer can be used as a clock
event device.
Unfortunately the use of the CP0 timer as a clock event device relies on a
succesful completion of c0_compare_interrupt. That never happens, because
while waiting for a CP0 Compare interrupt to happen the function spins in
a loop reading the CP0 Count register. This makes the CP0 Count erratum
trigger reliably causing the interrupt waited for to be lost in all cases.
As a result #4 resorts to using the CP0 timer as a clock source as well,
just as #2. However we want to keep this separate arrangement in case
(hope) c0_compare_interrupt is eventually rewritten such that it avoids
the erratum.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5825/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This change corrects DECstation HRT calibration, by removing the following
bugs:
1. Calibration period selection -- HZ / 10 has been chosen, however on
DECstation computers, HZ never divides by 10, as the choice for HZ is
among 128, 256 and 1024. The choice therefore results in a systematic
calibration error, e.g. 6.25% for the usual choice of 128 for HZ:
128 / 10 * 10 = 120
(128 - 120) / 128 -> 6.25%
The change therefore makes calibration use HZ / 8 that is always
accurate for the HZ values available, getting rid of the systematic
error.
2. Calibration starting point synchronisation -- the duration of a number
of intervals between DS1287A periodic interrupt assertions is measured,
however code does not ensure at the beginning that the interrupt has
not been previously asserted. This results in a variable error of e.g.
up to another 6.25% for the period of HZ / 8 (8.(3)% with the original
HZ / 10 period) and the usual choice of 128 for HZ:
1 / 16 -> 6.25%
1 / 12 -> 8.(3)%
The change therefore adds an initial call to ds1287_timer_state that
clears any previous periodic interrupt pending.
The same issue applies to both I/O ASIC counter and R4k CP0 timer
calibration on DECstation systems as similar code is used in both cases
and both pieces of code are covered by this fix.
On an R3400 test system used this fix results in a change of the I/O ASIC
clock frequency reported from values like:
I/O ASIC clock frequency 23185830Hz
to:
I/O ASIC clock frequency 24999288Hz
removing the miscalculation by 6.25% from the systematic error and (for
the individual sample provided) a further 1.00% from the variable error,
accordingly. The nominal I/O ASIC clock frequency is 25MHz on this
system.
Here's another result, with the fix applied, from a system that has both
HRTs available (using an R4400 at 60MHz nominal):
MIPS counter frequency 59999328Hz
I/O ASIC clock frequency 24999432Hz
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5807/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
promcon.o is built if CONFIG_PROM_CONSOLE is set. But there's no Kconfig
symbol PROM_CONSOLE, so promcon.c is unbuildable. Remove it.
Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Acked-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/5344/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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>
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.delinux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/2835/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Mark interrupts with no_action handler, cascade interrupts, low level
interrupts (bus error, halt ..) with IRQF_NO_THREAD to exclude them
from forced threading.
Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Cc: Wu Zhangjin <wuzhangjin@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Occasionally the system gets into a state where the CMOS clock has gotten
slightly ahead of current time and the periodic update of RTC fails. The
message is a nuisance and repeats spamming the log.
See: http://www.ntp.org/ntpfaq/NTP-s-trbl-spec.htm#Q-LINUX-SET-RTC-MMSS
Rather than just removing the message, make it show only once and reduce
severity since it indicates a normal and non urgent condition.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-2.6-irqflags:
Fix IRQ flag handling naming
MIPS: Add missing #inclusions of <linux/irq.h>
smc91x: Add missing #inclusion of <linux/irq.h>
Drop a couple of unnecessary asm/system.h inclusions
SH: Add missing consts to sys_execve() declaration
Blackfin: Rename IRQ flags handling functions
Blackfin: Add missing dep to asm/irqflags.h
Blackfin: Rename DES PC2() symbol to avoid collision
Blackfin: Split the BF532 BFIN_*_FIO_FLAG() functions to their own header
Blackfin: Split PLL code from mach-specific cdef headers
When running make clean, Kbuild doesn't process the .config file, so nothing
generates a platform-y variable. We can get it to descend into the platform
directories by setting $(obj-).
The dec Platform file was unconditionally setting platform-, obliterating
its previous contents and preventing some directories from being cleaned.
This is change to an append operation '+=' to allow cavium-octeon to be
cleaned.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Patchwork: https://patchwork.linux-mips.org/patch/1718/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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>
arch/mips/dec/promcon.c:37: ERROR: that open brace { should be on the previous line
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/1270/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* 'timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (34 commits)
time: Prevent 32 bit overflow with set_normalized_timespec()
clocksource: Delay clocksource down rating to late boot
clocksource: clocksource_select must be called with mutex locked
clocksource: Resolve cpu hotplug dead lock with TSC unstable, fix crash
timers: Drop a function prototype
clocksource: Resolve cpu hotplug dead lock with TSC unstable
timer.c: Fix S/390 comments
timekeeping: Fix invalid getboottime() value
timekeeping: Fix up read_persistent_clock() breakage on sh
timekeeping: Increase granularity of read_persistent_clock(), build fix
time: Introduce CLOCK_REALTIME_COARSE
x86: Do not unregister PIT clocksource on PIT oneshot setup/shutdown
clocksource: Avoid clocksource watchdog circular locking dependency
clocksource: Protect the watchdog rating changes with clocksource_mutex
clocksource: Call clocksource_change_rating() outside of watchdog_lock
timekeeping: Introduce read_boot_clock
timekeeping: Increase granularity of read_persistent_clock()
timekeeping: Update clocksource with stop_machine
timekeeping: Add timekeeper read_clock helper functions
timekeeping: Move NTP adjusted clock multiplier to struct timekeeper
...
Fix trivial conflict due to MIPS lemote -> loongson renaming.
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>
They tend to get not updated when files are moved around or copied and
lack any obvious use. While at it zap some only too obvious comments and
as per Shinya's suggestion, add a copyright header to extable.c.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Shinya Kuribayashi <shinya.kuribayashi@necel.com>
Acked-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Changes mips to use the new bcd2bin/bin2bcd functions instead of the
obsolete BCD_TO_BIN/BIN_TO_BCD/BCD2BIN/BIN2BCD macros.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hard to follow who is pointing what to where and why so it's simply getting
in the way of the time code renovation.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This has not been any serious user of this ill conceived thing since the
original invention in like '95.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Fix the definition of the ioasic_ssr_lock spinlock to include a proper
initialisation.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This is an optimised implementation of early printk() for the DECstation.
After the recent conversion to a MIPS-specific generic routine using a
character-by-character output the performance dropped significantly.
This change reverts to the previous speed -- even at 9600 bps of the
serial console the difference is visible with a naked eye; I presume for a
framebuffer it is even worse (it may depend on exactly which one is used
though).
Additionally the change includes a fix for a problem that the old
implementation had -- the format used would not actually limit the length
of the string output. This new implementation uses a local buffer to deal
with it -- even with this additional copying it is much faster than the
generic function.
Plus this driver is registered much earlier than the generic one,
allowing one to see critical messages, such as one about an incorrect CPU
setting used, that are produced beforehand. :-)
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Convert old/obsolete NORET_TYPE and ATTRIB_NORET macros to use the
newer standard of "__noreturn" as defined in compiler-gcc.h.
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Many Makefiles in arch/mips have EXTRA_AFLAGS := $(CFLAGS) line. This
is redundant while AFLAGS contains $(cflags-y) and any options only
listed in CFLAGS (not in cflags-y) should be unnecessary for asm
sources.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
When I post a patch (commit f431baa55a),
I just tried to not change behavior of existing codes, but it seems
dec/int-handler.S had been broken since its previous commit
937a801576.
The caller of plat_irq_dispatch do setup/restore TI_REGS($28), so
dec's plat_irq_dispatch should not do it, and there is no need to
adjust RA.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This is the platform-specific part of TURBOchannel bus support for the
DECstation. It implements determining whether the bus is actually there,
getting bus parameters, IRQ assignments for devices and protected accesses
to possibly unoccupied slots that may trigger bus error exceptions.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The "typename" field was obsoleted by the "name" field.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Current prom_free_prom_memory() implementations are almost same as
free_init_pages(), or no-op. Make free_init_pages() extern (again)
and make prom_free_prom_memory() use it.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The irq_base for {mips,rm7k,rm9k}_cpu_irq_init() are constant on all
platforms and are same value on most platforms (0 or 16, depends on
CONFIG_I8259). Define them in asm-mips/mach-generic/irq.h and make
them customizable. This will save a few cycle on each CPU interrupt.
A good side effect is removing some dependencies to MALTA in generic
SMTC code.
Although MIPS_CPU_IRQ_BASE is customizable, this patch changes irq
mappings on DDB5477, EMMA2RH and MIPS_SIM, since really customizing
them might cause some header dependency problem and there seems no
good reason to customize it. So currently only VR41XX is using custom
MIPS_CPU_IRQ_BASE value, which is 0 regardless of CONFIG_I8259.
Testing this patch on those platforms is greatly appreciated. Thank
you.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
A fixup to add missing header inclusions for bus error handlers for
DECstation system after the recent switch to get_irq_regs().
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
