MIPS R6 removed quite a few R2 instructions. However, there
is plenty of <R6 userland code so we add an in-kernel emulator
so we can still be able to execute all R2 userland out there.
The emulator comes with a handy debugfs under /mips/ directory
(r2-emul-stats) to provide some basic statistics of the
instructions that are being emulated.
Below are some statistics from booting a minimal buildroot image:
Instruction Total BDslot
------------------------------
movs 236969 0
hilo 56686 0
muls 55279 0
divs 10941 0
dsps 0 0
bops 1 0
traps 0 0
fpus 0 0
loads 214981 17
stores 103364 0
llsc 56898 0
dsemul 150418 0
jr 370158
bltzl 43
bgezl 1594
bltzll 0
bgezll 0
bltzal 39
bgezal 39
beql 14503
bnel 138741
blezl 0
bgtzl 3988
Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
This patch adds code to generate entry & exit code for various low power
states available on systems based around the MIPS Coherent Processing
System architecture (ie. those with a Coherence Manager, Global
Interrupt Controller & for >=CM2 a Cluster Power Controller). States
supported are:
- Non-coherent wait. This state first leaves the coherent domain and
then executes a regular MIPS wait instruction. Power savings are
found from the elimination of coherency interventions between the
core and any other coherent requestors in the system.
- Clock gated. This state leaves the coherent domain and then gates
the clock input to the core. This removes all dynamic power from the
core but leaves the core at the mercy of another to restart its
clock. Register state is preserved, but the core can not service
interrupts whilst its clock is gated.
- Power gated. This deepest state removes all power input to the core.
All register state is lost and the core will restart execution from
its BEV when another core powers it back up. Because register state
is lost this state requires cooperation with the CONFIG_MIPS_CPS SMP
implementation in order for the core to exit the state successfully.
The code will detect which states are available on the current system
during boot & generate the entry/exit code for those states. This will
be used by cpuidle & hotplug implementations.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Nobody is maintaining SMTC anymore and there also seems to be no userbase.
Which is a pity - the SMTC technology primarily developed by Kevin D.
Kissell <kevink@paralogos.com> is an ingenious demonstration for the MT
ASE's power and elegance.
Based on Markos Chandras <Markos.Chandras@imgtec.com> patch
https://patchwork.linux-mips.org/patch/6719/ which while very similar did
no longer apply cleanly when I tried to merge it plus some additional
post-SMTC cleanup - SMTC was a feature as tricky to remove as it was to
merge once upon a time.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Add a CPU power management notifier callback for preserving general CPU
context. The CPU PM callbacks will be triggered by the powering down of
CPU cores, for example by cpuidle drivers & in the future by suspend to
RAM implementations.
The current state preserved is mostly related to the process context:
- FPU
- DSP
- ASID
- UserLocal
- Watch registers
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
The kernel currently only probes for a MIPS Coherence Manager in the
Malta interrupt code in order to detect & enable the GIC. However CM is
not Malta-specific, so this should really be more generic. This patch
introduces some non-Malta-specific code which probes for a CM and
performs some basic initialisation.
A new header, with temporarily duplicated register definitions, is
introduced in order to:
1) Allow the new definitions to be correct with regards to the
CM documentation, as many of those in gcmpregs.h aren't.
2) Allow switching away from the REG() macro used via a few layers of
nested macros in order to access registers in gcmpregs.h. This
patch instead introduced accessor functions akin to the
{read,write}_c0_* functions used for cop0 registers.
3) Allow users of the CM to be migrated one by one.
4) Switch from the name 'GCMP' to 'CM' since the Coherence Manager is
what this code is actually dealing with.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6360/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The GIC IPI functions aren't necessarily specific to the "CMP
framework" SMP implementation, and will be used elsewhere in a
subsequent commit. This patch adds cleaned up GIC IPI functions to a
separate file which is compiled when a new CONFIG_MIPS_GIC_IPI Kconfig
symbol is selected, and selects that symbol for CONFIG_MIPS_CMP.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6359/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Add a new mips/segments debugfs file to print the 6 segmentation
control registers for supported cores. A sample from a proAptiv core
is given below:
Signed-off-by: John Crispin <blogic@openwrt.org>
Patchwork: http://patchwork.linux-mips.org/patch/6137/
Segment Virtual Size Access Mode Physical Caching EU
------- ------- ---- ----------- -------- ------- --
0 e0000000 512M MK UND U 0
1 c0000000 512M MSK UND U 0
2 a0000000 512M UK 000 2 0
3 80000000 512M UK 000 3 0
4 40000000 1G MUSK UND U 1
5 00000000 1G MUSK UND U 1
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Steven J. Hill <Steven.Hill@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Nobody seems to care about this platform anymore and my attempts to find
somebody willing to provide some tlc for PowerTV have failed so far.
So let's nuke the bloody thing.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Patchwork: https://patchwork.linux-mips.org/patch/5910/
