Before we configure the early UART, check to make sure we are running on
the expected processor - otherwise, we cause problems by configuring pins
that don't exist (and causing an infinite loop of faults).
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

When a low priority interrupt (like ethernet) is triggered between 2 high
priority IPI messages, a deadlock in disable_irq() is hit by the second
IPI handler.  This is because the second IPI message is queued within the
first IPI handler, but the handler doesn't process all messages, and new
ones are inserted rather than appended.  So now we process all the pending
messages, and append new ones to the pending list.

URL: http://blackfin.uclinux.org/gf/tracker/5226Signed-off-by: NSonic Zhang <sonic.zhang@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

The IRQ functions take an "unsigned long" flags variable, not any other
type, so fix the places where we use "int" or "long".
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

Rather than maintain a duplicate list of valid exceptions we can take in
the kernel both in the first if() check and the switch() check, delay the
oops check to after the switch().  All valid exceptions will have returned
by this point leaving only the invalid ones.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

The trap_c() code pushes the hardware trace status onto the stack, but
doesn't always restore it when returning from some trap code paths.  So
unify the exit code paths to all head to the end of the function.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

The KGDB code uses this when switching processors to make sure the icache
is in a valid state.
Signed-off-by: NSonic Zhang <sonic.zhang@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

Since the compiled-for cpu revision can be significant, include it in the
cpuinfo output along side the cpu revision we're currently running on.
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

Signed-off-by: NMike Frysinger <vapier@gentoo.org>

The latter naming convention is much more common.
Signed-off-by: NJie Zhang <jie.zhang@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

All other arches do this, and some places like the net/scsi code will fail
as modules without them.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

We don't need to handle CPLB protection violations unless we are running
with the MPU on.  Fix the entry code to call common trap_c, and remove the
code which is never run.  This allows the traps test suite to run on older
boards with the MPU disabled.

URL: http://blackfin.uclinux.org/gf/tracker/5129Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

The sparseirq changes (d7e51e66) played poorly with the Blackfin irqchip
implementation as we're still using the old hardirq method.  Our bad irq
structure had a NULL kstat_irqs field so when all the common code tries
to increment this field, everything goes big bada boom.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

The massive nommu update (8feae131) left the local variable "vml" unused,
so punt it.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

We have some test code that runs in userspace that exercises the exception
handling of the Blackfin pretty thoroughly.  Part of the validation process
is checking the exact exception triggered, so export the last one seen to
userspace via debugfs when debugging is enabled for the test code to check.
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

The kgdb_ebin2mem() was decrementing the count variable to do parsing, but
then later still tries to use it based on its original meaning.  So leave
it untouched and use a different variable to walk the memory.
Signed-off-by: NRoel Kluin <roel.kluin@gmail.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

The Blackfin kgdb code was all passing back positive errno values when it
really should have been using negative errno values.
Reported-by: NRoel Kluin <roel.kluin@gmail.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

There is no need for the L1 attribute to be on the prototype of the
access_ok() function as all consumers of the function do not care where it
lives -- they'll always use pcrel calls to get to it.  This prevents
pointless recompiles of most of the system when this config option changes.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

The common code already has a prototype for this function and we don't use
it anywhere in the Blackfin code, so punt it from the Blackfin headers.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

The core string/clear user functions weren't checking the user pointers
which caused kernel crashes with some bad programs and tests (like LTP).
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

The EVT registers are all contiguous in the memory map, so using a loop to
initialize them all rather than hardcoding the list results in much better
generated code (a hardware loop rather than a whole bunch of individual
loads).
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

Make sure the meaning of "lsl" is covered somewhere and it is clear why we
somewhat duplicate the sram alloc/free functions.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

The latest Blackfin toolchain has fixed its relocation scheme to match
other ports: always use R_BFIN_ prefix and capitalize everything.  This
brings the kernel in line with those fixes.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

Rather than having to maintain a hard coded list of Blackfin variants, use
the SIC defines themselves.  This fixes build problems on BF51x/BF538 under
some configurations as they were missing from one of the lists.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

Make sure the internal core buffers are flushed before telling the DMA
engine to fetch the descriptor structure so that it gets the right values.
Signed-off-by: NSonic Zhang <sonic.zhang@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

Signed-off-by: NGraf Yang <graf.yang@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

Due to a processor anomaly (05000263 to be exact), most Blackfin parts
cannot keep the embedded filesystem image directly after the kernel in
RAM.  Instead, the filesystem needs to be relocated to the end of memory.
As such, we need to tweak the map addr/size during boot for Blackfin
systems.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

Commit 6b3087c6 (which introduced Blackfin SMP) broke command line passing
when the DEBUG_DOUBLEFAULT config option was enabled.  Switch the code to
using a scratch register and not R7 which holds the command line.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

This restores some L1 reservation logic that was lost during the Blackfin
SMP merge.
Signed-off-by: NGraf Yang <graf.yang@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

Now that the sram_init() function exists only to call the bfin_sram_init()
after the punting of the reserve_pda() function, simply merge the two to
avoid pointless overhead.
Signed-off-by: NGraf Yang <graf.yang@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

The Per-processor Data Area isn't actually reserved by this function, and
all it ended up doing was issuing a printk(), so punt it.
Signed-off-by: NGraf Yang <graf.yang@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

First we fix the prototypes for functions that return boolean values by
using "int" rather than "uint16_t".  Then we introduce a get_gptimer_run()
function for checking the current run status of a timer, and then we add a
disable_gptimers_sync() function which parallels disable_gptimers() with
corresponding normal "_sync" behavior.
Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

People often copy & paste crash messages without surrounding context, so
include common useful information like system/processor stats in the crash
summary.  This should smooth over the report/test cycle a bit more.
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

Returning too fast with a bad RETI can trigger false errors.
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

When displaying a crash dump, make sure accessing the stack is safe so
we don't crash at the same time.
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

Hardware errors on the Blackfin architecture are queued by nature of the
hardware design.  Things that could generate a hardware level queue up at
the system interface and might not process until much later, at which
point the system would send a notification back to the core.

As such, it is possible for user space code to do something that would
trigger a hardware error, but have it delay long enough for the process
context to switch.  So when the hardware error does signal, we mistakenly
evaluate it as a different process or as kernel context and panic (erp!).
This makes it pretty difficult to find the offending context.  But wait,
there is good news somewhere.

By forcing a SSYNC in the interrupt entry, we force all pending queues at
the system level to be processed and all hardware errors to be signaled.
Then we check the current interrupt state to see if the hardware error is
now signaled.  If so, we re-queue the current interrupt and return thus
allowing the higher priority hardware error interrupt to process properly.
Since we haven't done any other context processing yet, the right context
will be selected and killed.  There is still the possibility that the
exact offending instruction will be unknown, but at least we'll have a
much better idea of where to look.

The downside of course is that this causes system-wide syncs at every
interrupt point which results in significant performance degradation.
Since this situation should not occur in any properly configured system
(as hardware errors are triggered by things like bad pointers), make it a
debug configuration option and disable it by default.
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

Document anomaly 05000242 workaround in source code.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

When possible, work around anomaly 05000220 (external memory is write
back cached, but L2 is not cached).  If not possible, detect the
conditions at build time and reject any qualifying configurations.
Signed-off-by: NGraf Yang <graf.yang@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

Try to keep the naming conventions consistent, so:
	SPI_ADC_BF533 -> BFIN_SPI_ADC
	TWI_LCD       -> BFIN_TWI_LCD
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

This way we properly catch and kill applications that jump to a NULL ptr.
Signed-off-by: NRobin Getz <robin.getz@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>