When GDB writes a breakpoint into address area of inferior process the
kernel needs to invalidate the modified memory in the inferior which
is done by calling flush_cache_page which in turns calls
r4k_flush_cache_page and local_r4k_flush_cache_page for VSMP or SMTC
kernel via r4k_on_each_cpu().
As the VSMP and SMTC SMP kernels for 34K are running on a single shared
caches it is possible to get away without interprocessor function calls.
This optimization is implemented in r4k_on_each_cpu, so
local_r4k_flush_cache_page is only ever called on the local CPU.
This is where the following code in local_r4k_flush_cache_page() strikes:
/*
* If ownes no valid ASID yet, cannot possibly have gotten
* this page into the cache.
*/
if (cpu_context(smp_processor_id(), mm) == 0)
return;
On VSMP and SMTC had a function of cpu_context() for each CPU(TC).
So in case another CPU than the CPU executing local_r4k_cache_flush_page
has not accessed the mm but one of the other CPUs has there may be data
to be flushed in the cache yet local_r4k_cache_flush_page will falsely
return leaving the I-cache inconsistent for the breakpoint.
While the issue was discovered with GDB it also exists in
local_r4k_flush_cache_range() and local_r4k_flush_cache().
Fixed by introducing a new function has_valid_asid which on MT kernels
returns true if a mm is active on any processor in the system.
This is relativly expensive since for memory acccesses in that loop
cache misses have to be assumed but it seems the most viable solution
for 2.6.23 and older -stable kernels.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Enable the onboard GenBus IDE interface in the default configuration.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Contrary to the belief of some, the R3000 and related processors did have
caches, both a data and an instruction cache. Here is an implementation
of r3k_flush_cache_page(), which is the processor-specific back-end for
flush_cache_range(), done according to the spec in
Documentation/cachetlb.txt.
While at it, remove an unused local function: get_phys_page(), do some
trivial formatting fixes and modernise debugging facilities.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
A comment on ptrace_getregs() states "Registers are sign extended to
fill the available space." but it is not true. Fix code to match the
comment. Also fix casts on each caller to get rid of some warnings.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This patch separates the platform devices registration for the MTX-1
specific devices: GPIO leds and watchdog.
[Minor fixup and formatting change -- Ralf]
Signed-off-by: Florian Fainelli <florian.fainelli@telecomint.eu>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Mmap with MAP_FIXED was not validating the addr and len parameters. This
leads to the failure of GCC's gcc.c-torture/execute/loop-2[fg].c testcases
when using the o32 ABI on a 64 bit kernel.
These testcases try to mmap 65536 bytes at 0x7fff8000 and then access all
the memory. In 2.6.18 and 2.6.23.1 (and likely other versions as well)
the kernel maps the requested memory, but since half of it is above
0x80000000 a SIGBUS is generated when it is accessed.
This patch moves the len validation above the MAP_FIXED processing so that
it is always validated. It also adds validation to the addr parameter for
MAP_FIXED mappings.
Signed-off-by: David Daney <ddaney@avtrex.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
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>
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>
They break the timer interrupt initialization and only seem to be a kludge
for initialization happening in the wrong order. Further testing done by
Thiemo confirms the suspicion that the other invocations also seem to have
useless.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Convert jmr3927_clock_event_device to more generic
txx9tmr_clock_event_device which supports one-shot mode. The
txx9tmr_clock_event_device can be used for TX49 too if the cp0 timer
interrupt was not available.
Convert jmr3927_hpt_read to txx9_clocksource driver which does not
depends jiffies anymore. The txx9_clocksource itself can be used for
TX49, but normally TX49 uses higher precision clocksource_mips.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Fixme: At the time of this writing cevt-r4k.c doesn't yet know about how
to handle the alternate timer interrupt of the RM9000.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Since the cp0 compare interrupt handler isn't initialized by the time
plat_time_init is called don't set IE_IRQ5 anymore, cevt-r4k.c will do
that a little later itself.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The old plat_timer_setup hook is no longer getting called so the Alchemy
time initialization was getting skipped.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
clockevent_delta2ns() use the shift and mult value, so
clockevent_set_clock() should be called first.
Pointed out by Atsushi Nemoto.
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
set_next_event() and set_mode() are always called with interrupt disabled.
irqsave and irqrestore are not necessary for spinlock.
Pointed out by Atsushi Nemoto.
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Modify the SMTC initialization code to allow boot-time specification not
only of how many VPEs and TCs to use, but also how many TCs out of the
allowed pool are to be bound to VPE 0. The new boot option is "vpe0tcs=N",
where N is an integer. Using it in combination with the existing options
allows arbitrary assignments across the 2 VPEs of a 34K. e.g. "maxtcs=3
vpe0tcs=1" forces VPE0 to have 1 TC, while VPE1 has 2, and "maxtcs=4
vpe0tcs=3" forces VPE0 to have 3 TCs, while VPE1 gets 1. If no vpe0tcs
option is specified, the traditional algorithm of evenly dividing TCs
between available VPEs, with the odd "slop" going to VPE0, is retained.
The reason for doing this is to allow a finer balancing of TCs which can
handle I/O interrupts on Malta (those on VPE 0) and those which cannot.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
[MIPS] time: Make c0_compare_int_usable more bullet proof
[MIPS] Kbuild: Use the new cc-cross-prefix feature.
[MIPS] Fix include wrapper symbol to something sane.
[MIPS] Malta: Delete dead code.
[MIPS] time: Add GT641xx timer0 clockevent driver
[MIPS] time: SMP-proofing of Sibyte clockevent/clocksource code.
[MIPS] time: SMP/NUMA-proofing of IP27 HUB RT timer code.
[MIPS] time: Fix calculation in clockevent_set_clock()
And make use of it for Cobalt. A few others such as the Malta could make
use of it as well.
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The BCM148 has 4 cores but there are also just 4 generic timers available
so use the ZBbus cycle counter instead of it. In addition the ZBbus
counter also offers a much higher resolution and 64-bit counting so I'm
considering a later complete conversion to it once I figure out if all
members of the Sibyte SOC family support it - the docs seem to agree but
the headers files seem to disagree ...
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Most of these fixes were already submitted for old kernel versions, and were
approved, but for some reason they never made it into the releases.
Because this is a consolidation of a couple old missed patches, it touches both
Kconfigs and documentation texts.
Signed-off-by: Matt LaPlante <kernel1@cyberdogtech.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Fix the various misspellings of "system", controller", "interrupt" and
"[un]necessary".
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus:
[MIPS] Delete totally outdated Documentation/mips/time.README
[MIPS] Kill duplicated setup_irq() for cp0 timer
[MIPS] Sibyte: Finish conversion to modern time APIs.
[MIPS] time: Helpers to compute clocksource/event shift and mult values.
[MIPS] SMTC: Build fix.
[MIPS] time: Delete dead code.
[MIPS] MIPSsim: Strip defconfig file to the bones.
