Rename setup_txprivext() to setup_priv() and add initialisation of some
more per-thread privilege protection registers:
- TxPRIVSYSR: 0x04400000-0x047fffff
0x05000000-0x07ffffff
0x84000000-0x87ffffff
- TxPIOREG: 0x02000000-0x02ffffff
0x04800000-0x048fffff
- TxSYREG: 0x04000000-0x04000fff (except write fetch system event)
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Define PRIV_BITS using explicit constants from <asm/metag_regs.h> rather
than with a hard coded value. This also adds a couple of missing
definitions for the TXPRIVEXT priv bits for protecting writes to TXTIMER
and the trace registers.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Add boot time check for whether LNKGET/LNKSET go through or around the
cache. Depending on the configuration an info message (no harm), warning
(technically wrong but no harm), or big WARN (expect failure in either
kernel or userland) may be emitted if the behaviour is not as expected:
Configuration Hardware Response
------------------------------------------ -------- --------
AROUND_CACHE through pr_info
!AROUND_CACHE && ATOMICITY_LNKGET around WARN (kernel)
" && !ATOMICITY_LNKGET && SMP around WARN (user)
" " && !SMP around pr_warn
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Add basic JTAG Debug Adapter (DA) support so that drivers which
communicate with the DA can detect whether one is actually present
(otherwise the target will halt indefinitely).
This allows the metag_da TTY driver and imgdafs filesystem driver to be
built, updates defconfigs, and sets up the metag_da console early if
it's configured in.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Commit cc2383ec06 ("mm: introduce
arch-specific vma flag VM_ARCH_1") merged in v3.7-rc1.
The above commit combined several arch-specific vma flags into one, and
in the process it changed the VM_GROWSUP definition to depend on
specific architectures rather than CONFIG_STACK_GROWSUP. Therefore add
an ifdef for CONFIG_METAG to also set VM_GROWSUP.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michel Lespinasse <walken@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-mm@kvack.org
Add SMP support for metag. This allows Linux to take control of multiple
hardware threads on a single Meta core, treating them as separate Linux
CPUs.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Add header files to implement Meta hardware thread locks (used by some
other atomic operations), atomics, spinlocks, and bitops.
There are 2 main types of atomic primitives for metag (in addition to
IRQs off on UP):
- LOCK instructions provide locking between hardware threads.
- LNKGET/LNKSET instructions provide load-linked/store-conditional
operations allowing for lighter weight atomics on Meta2
LOCK instructions allow for hardware threads to acquire voluntary or
exclusive hardware thread locks:
- LOCK0 releases exclusive and voluntary lock from the running hardware
thread.
- LOCK1 acquires the voluntary hardware lock, blocking until it becomes
available.
- LOCK2 implies LOCK1, and additionally acquires the exclusive hardware
lock, blocking all other hardware threads from executing.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Add metag system call and gateway page interfaces. The metag
architecture port uses the generic system call numbers from
asm-generic/unistd.h, as well as a user gateway page mapped at
0x6ffff000 which contains fast atomic primitives (depending on SMP) and
a fast method of accessing TLS data.
System calls use the SWITCH instruction with the immediate 0x440001 to
signal a system call.
Signed-off-by: James Hogan <james.hogan@imgtec.com>