MT_SMP is not the only SMP option for MT cores. The MT_SMP option
allows more than one VPE per core to appear as a secondary CPU in the
system. Because of how CM works, it propagates the address-based
cache ops to the secondary cores but not the index-based ones.
Because of that, the code does not use IPIs to flush the L1 caches on
secondary cores because the CM would have done that already. However,
the CM functionality is independent of the type of SMP kernel so even in
non-MT kernels, IPIs are not necessary. As a result of which, we change
the conditional to depend on the CM presence. Moreover, since VPEs on
the same core share the same L1 caches, there is no need to send an
IPI on all of them so we calculate a suitable cpumask with only one
VPE per core.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: <stable@vger.kernel.org> # 3.15+
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10654/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The PTR_LA macro will pick the correct "la" or "dla" macro to
load an address to a register. This gets rids of the following
warnings (and others) when building a 64-bit CPS kernel:
arch/mips/kernel/cps-vec.S:63: Warning: la used to load 64-bit address
arch/mips/kernel/cps-vec.S:159: Warning: la used to load 64-bit address
arch/mips/kernel/cps-vec.S:220: Warning: la used to load 64-bit address
arch/mips/kernel/cps-vec.S:240: Warning: la used to load 64-bit address
[...]
Cc: <stable@vger.kernel.org> # 3.16+
Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/10587/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit 1d8f1f5a78 ("MIPS: smp-cps: hotplug support") added hotplug
support in the SMP/CPS implementation but it introduced a few build problems
on 64-bit kernels due to pointer being casted to and from 'int' C types. We
fix this problem by using 'unsigned long' instead which should match the size
of the pointers in 32/64-bit kernels. Finally, we fix the comment since the
CM base address is loaded to v1($3) instead of v0.
Fixes the following build problems:
arch/mips/kernel/smp-cps.c: In function 'wait_for_sibling_halt':
arch/mips/kernel/smp-cps.c:366:17: error: cast from pointer to integer of
different size [-Werror=pointer-to-int-cast]
[...]
arch/mips/kernel/smp-cps.c: In function 'cps_cpu_die':
arch/mips/kernel/smp-cps.c:427:13: error: cast to pointer
from integer of different size [-Werror=int-to-pointer-cast]
cc1: all warnings being treated as errors
Fixes: 1d8f1f5a78 ("MIPS: smp-cps: hotplug support")
Cc: <stable@vger.kernel.org> # 3.16+
Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: stable@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/10586/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commits f1b44067c1 ("MIPS: Emulate the
new MIPS R6 B{L,G}T{Z,}{AL,}C instructions") and commit
a8ff66f52d ("MIPS: Emulate the new MIPS
R6 B{L,G}E{Z,}{AL,}C instructions") added support for emulating various
branch compact instructions. However, it missed the case for those which
use the old BLEZL and BGTZL opcodes leading to random crashes when the R6
emulator is disabled. We fix this by ensuring that the 'rt' field is not
zero which is always true for these branch compact instructions.
Fixes: f1b44067c1 ("MIPS: Emulate the new MIPS R6 B{L,G}T{Z,}{AL,}C instructions")
Fixes: a8ff66f52d ("MIPS: Emulate the new MIPS R6 B{L,G}E{Z,}{AL,}C instructions")
Cc: <stable@vger.kernel.org> # 4.0+
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: https://patchwork.linux-mips.org/patch/10582/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit f9a7febd leads to a fact that mapstart and therefore a page bitmap for
bootmem allocator immediately follows initrd_end. This doesn't always work
well on Octeon, where there are holes in PFN ranges (refer to 5b3b1688 and
4MB-aligned PFN allocation). Depending on the inird location it could happen,
that mapstart would be in an area not allocated by plat_mem_setup() in
arch/mips/cavium-octeon/setup.c, but in the alignment hole between initrd and
the next PFN area. Later on this memory will be unconditionally made available
to buddy allocator at the end of free_all_bootmem_core() (mm/bootmem.c).
All of this results in Linux using the memory not designated for Linux in
Octeon's plat_mem_setup(), which in turn means corruption of the memory used
by another OS/baremetal code on the same SoC.
It doesn't look to me as a problem of Octeon platform code, but rather as an
inability of f9a7febd to deal correctly with the fragmented memory-mappings.
Proposed fix moves the check for initrd address to the same calculation-loop
in bootmem_init() (arch/mips/kernel/setup.c), which also accounts for kernel
code location. This should result in mapstart located starting from the first
PFN area after kernel code AND initrd.
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Cc: linux-mips@linux-mips.org
Cc: David Daney <david.daney@cavium.com>
Cc: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@imgtec.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: Andreas Herrmann <andreas.herrmann@caviumnetworks.com>
Cc: Joe Perches <joe@perches.com>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Yusuf Khan <yusuf.khan@nokia.com>
Cc: Michael Kreuzer <michael.kreuzer@nokia.com>
Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Patchwork: https://patchwork.linux-mips.org/patch/10594/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit 46e12c07b3 (MIPS: O32 / 32-bit:
Always copy 4 stack arguments.) change the O32 syscall handler to always
load four arguments from the userspace stack even for syscalls that
require fewer or no arguments to be copied. This removes a large table
from kernel space and need to maintain it. It appeared that it was ok
the implementation chosen requires 16 bytes of readable stack space
above the user stack pointer.
Turned out a few threading implementations munmap the user stack before
the thread exits resulting in errors due to the unreadable stack.
We now treat any failed load as a if the loaded value was zero and let
the actual syscall deal with the situation.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Pull MIPS updates from Ralf Baechle:
- Improvements to the tlb_dump code
- KVM fixes
- Add support for appended DTB
- Minor improvements to the R12000 support
- Minor improvements to the R12000 support
- Various platform improvments for BCM47xx
- The usual pile of minor cleanups
- A number of BPF fixes and improvments
- Some improvments to the support for R3000 and DECstations
- Some improvments to the ATH79 platform support
- A major patchset for the JZ4740 SOC adding support for the CI20 platform
- Add support for the Pistachio SOC
- Minor BMIPS/BCM63xx platform support improvments.
- Avoid "SYNC 0" as memory barrier when unlocking spinlocks
- Add support for the XWR-1750 board.
- Paul's __cpuinit/__cpuinitdata cleanups.
- New Malta CPU board support large memory so enable ZONE_DMA32.
* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus: (131 commits)
MIPS: spinlock: Adjust arch_spin_lock back-off time
MIPS: asmmacro: Ensure 64-bit FP registers are used with MSA
MIPS: BCM47xx: Simplify handling SPROM revisions
MIPS: Cobalt Don't use module_init in non-modular MTD registration.
MIPS: BCM47xx: Move NVRAM driver to the drivers/firmware/
MIPS: use for_each_sg()
MIPS: BCM47xx: Don't select BCMA_HOST_PCI
MIPS: BCM47xx: Add helper variable for storing NVRAM length
MIPS: IRQ/IP27: Move IRQ allocation API to platform code.
MIPS: Replace smp_mb with release barrier function in unlocks.
MIPS: i8259: DT support
MIPS: Malta: Basic DT plumbing
MIPS: include errno.h for ENODEV in mips-cm.h
MIPS: Define GCR_GIC_STATUS register fields
MIPS: BPF: Introduce BPF ASM helpers
MIPS: BPF: Use BPF register names to describe the ABI
MIPS: BPF: Move register definition to the BPF header
MIPS: net: BPF: Replace RSIZE with SZREG
MIPS: BPF: Free up some callee-saved registers
MIPS: Xtalk: Update xwidget.h with known Xtalk device numbers
...
Pull scheduler updates from Ingo Molnar:
"The main changes are:
- lockless wakeup support for futexes and IPC message queues
(Davidlohr Bueso, Peter Zijlstra)
- Replace spinlocks with atomics in thread_group_cputimer(), to
improve scalability (Jason Low)
- NUMA balancing improvements (Rik van Riel)
- SCHED_DEADLINE improvements (Wanpeng Li)
- clean up and reorganize preemption helpers (Frederic Weisbecker)
- decouple page fault disabling machinery from the preemption
counter, to improve debuggability and robustness (David
Hildenbrand)
- SCHED_DEADLINE documentation updates (Luca Abeni)
- topology CPU masks cleanups (Bartosz Golaszewski)
- /proc/sched_debug improvements (Srikar Dronamraju)"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (79 commits)
sched/deadline: Remove needless parameter in dl_runtime_exceeded()
sched: Remove superfluous resetting of the p->dl_throttled flag
sched/deadline: Drop duplicate init_sched_dl_class() declaration
sched/deadline: Reduce rq lock contention by eliminating locking of non-feasible target
sched/deadline: Make init_sched_dl_class() __init
sched/deadline: Optimize pull_dl_task()
sched/preempt: Add static_key() to preempt_notifiers
sched/preempt: Fix preempt notifiers documentation about hlist_del() within unsafe iteration
sched/stop_machine: Fix deadlock between multiple stop_two_cpus()
sched/debug: Add sum_sleep_runtime to /proc/<pid>/sched
sched/debug: Replace vruntime with wait_sum in /proc/sched_debug
sched/debug: Properly format runnable tasks in /proc/sched_debug
sched/numa: Only consider less busy nodes as numa balancing destinations
Revert 095bebf61a ("sched/numa: Do not move past the balance point if unbalanced")
sched/fair: Prevent throttling in early pick_next_task_fair()
preempt: Reorganize the notrace definitions a bit
preempt: Use preempt_schedule_context() as the official tracing preemption point
sched: Make preempt_schedule_context() function-tracing safe
x86: Remove cpu_sibling_mask() and cpu_core_mask()
x86: Replace cpu_**_mask() with topology_**_cpumask()
...
allocate_irqno, free_irqno and alloc_legacy_irqno are a simple allocator
for interrupt numbers from the days when the numer of interrupts was still
fixed to NR_IRQS. This was necessary for the SGI IP27 architecture which
with its flexible architecture and possibly large number of interrupts
doesn't easily fit into the old pattern. These days there are better
alternatives.
Move the allocation code from the arch generic code to the only platform
using it, the SGI IP27 aka Origin 200/2000, Onyx 2.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
In preparation to allow users to enable DeviceTree without arch or
machine selecting it, we need to fix build errors on MIPS. When
CONFIG_OF is enabled, device_tree_init cannot be resolved. This is
trivially fixed by using CONFIG_USE_OF instead of CONFIG_OF for prom.h.
Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
The R12000 added a new feature to enhance branch prediction called
"global history". Per the Vr10000 Series User Manual (U10278EJ4V0UM),
Coprocessor 0, Diagnostic Register (22):
"""
If bit 26 is set, branch prediction uses all eight bits of the global
history register. If bit 26 is not set, then bits 25:23 specify a count
of the number of bits of global history to be used. Thus if bits 26:23
are all zero, global history is disabled.
The global history contains a record of the taken/not-taken status of
recently executed branches, and when used is XOR'ed with the PC of a
branch being predicted to produce a hashed value for indexing the BPT.
Some programs with small "working set of conditional branches" benefit
significantly from the use of such hashing, some see slight performance
degradation.
"""
This patch enables global history on R12000 CPUs and up by setting bit
26 in the branch prediction diagnostic register (CP0 $22) to '1'. Bits
25:23 are left alone so that all eight bits of the global history
register are available for branch prediction.
Signed-off-by: Joshua Kinard <kumba@gentoo.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Commit 854700115ecf ([MIPS] kgdb: add arch support for the kernel's kgdb core)
added the 'kgdb_early_setup' flag to avoid calling trap_init() and init_IRQ()
the second time, however the code that called these functions earlier, from
kgdb_arch_init(), had been already removed by that time, so the flag never
served any useful purpose. Remove the related code along with ugly #ifdef'ery
at last.
[ralf@linux-mips.org: Folded in Guenter Roeck's fix.]
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Patchwork: https://patchwork.linux-mips.org/patch/10501/
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Patchwork: https://patchwork.linux-mips.org/patch/10533/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
