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>
There are no I/O ports on the DECstation whatsoever in any configuration
as neither the CPU nor the peripheral buses used have a concept of such.
Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Enable Cobalt button support and change ATA driver from BLK_DEV_VIA82CXXX
to PATA_VIA..
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
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>
This patch adds support for the generic GPIO API to Au1x00 boards. It requires
the generic GPIO patch for MIPS boards by Yoichi Yuasa. Now there is a MIPS
target using it, can you queue these patchset for 2.6.22 ? Thank you very
much in advance.
Signed-off-by: Florian Fainelli <florian.fainelli@telecomint.eu>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Use standard missing-syscalls with EXTRA_CFLAGS instead of duplicating
the command. And move the archprepare rule before the archclean rule.
Suggested by Franck Bui-Huu. Also add "echo" to show the target ABI.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
the SMP load-balancer uses the boot-time migration-cost estimation
code to attempt to improve the quality of balancing. The reason for
this code is that the discrete priority queues do not preserve
the order of scheduling accurately, so the load-balancer skips
tasks that were running on a CPU 'recently'.
this code is fundamental fragile: the boot-time migration cost detector
doesnt really work on systems that had large L3 caches, it caused boot
delays on large systems and the whole cache-hot concept made the
balancing code pretty undeterministic as well.
(and hey, i wrote most of it, so i can say it out loud that it sucks ;-)
under CFS the same purpose of cache affinity can be achieved without
any special cache-hot special-case: tasks are sorted in the 'timeline'
tree and the SMP balancer picks tasks from the left side of the
tree, thus the most cache-cold task is balanced automatically.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The idle loop goes to sleep using the WAIT instruction if !need_resched().
This has is suffering from from a race condition that if if just after
need_resched has returned 0 an interrupt might set TIF_NEED_RESCHED but
we've just completed the test so go to sleep anyway. This would be
trivial to fix by just disabling interrupts during that sequence as in:
local_irq_disable();
if (!need_resched())
__asm__("wait");
local_irq_enable();
but the processor architecture leaves it undefined if a processor calling
WAIT with interrupts disabled will ever restart its pipeline and indeed
some processors have made use of the freedom provided by the architecture
definition. This has been resolved and the Config7.WII bit indicates that
the use of WAIT is safe on 24K, 24KE and 34K cores. It also is safe on
74K starting revision 2.1.0 so enable the use of WAIT with interrupts
disabled for 74K based on a c0_prid of at least that.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Reported by Eugene Surovegin <ebs@ebshome.net>.
If only modules were users of these functions they did not get linked into
the kernel proper, so later module loads would fail as well.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
C0_status doesn't need to be initialized at this point anyway; the register
will be initialized later.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Neither rtc_mips_get_time nor rtc_mips_set_time are being initialized by
the EMMA2RH setup code, so genrtc at best was a RTC dummy avoiding a few
error messages but not providing actual functionality.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
We used to avoid the WAIT entirely on the 20K but really only need to do
this on early revs of the 20K. Without this a 20K was a bit of a
power hog. Well, in the lower power power hog category ;-)
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
For some platforms it's definitions may conflict. So that's the one-liner.
The rest is 10 square kilometers of collateral damage fixup this include
used to paper over.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Support for performance counter overflow interrupt that is on a separate
interrupt from the timer.
Signed-off-by: Chris Dearman <chris@mips.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
And an attempt to tidy up the core/controller differences.
Signed-off-by: Chris Dearman <chris@mips.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Some non-DSP enabled cores 24K / 34K can generate a DSP exception where they
are actually expected to produce a reserved instruction exception.
Signed-off-by: Chris Dearman <chris@mips.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This did corrupt register s0 which the caller of self_ipi expects to
be unchanged. This is a kernel bug which will only be triggered with
the compilers which compile __smtc_ipi_replay to use s0 across the
invocation of self_ipi. Gcc 4.1.2 does this, for example.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This fixes the warning:
arch/mips/kernel/traps.c:931: warning: 'do_default_vi' defined but not used
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Yoichi Yuasa