Commit Graph

20 Commits

Author SHA1 Message Date
Stefan Kalkowski
f842c92ee1 hw: correct the ARM cache maintainance operations
This commit fixes the following issues regarding cache maintainance
under ARM:

* read out I-, and D-cache line size at runtime and use the correct one
* remove 'update_data_region' call from unprivileged syscalls
* rename 'update_instr_region' syscall to 'cache_coherent_region' to
  reflect what it doing, namely make I-, and D-cache coherent
* restrict 'cache_coherent_region' syscall to one page at a time
* lookup the region given in a 'cache_coherent_region' syscall in the
  page-table of the PD to prevent machine exceptions in the kernel
* only clean D-cache lines, do not invalidate them when pages where
  added on Cortex-A8 and ARMv6 (MMU sees phys. memory here)
* remove unused code relicts of cache maintainance

In addition it introduces per architecture memory clearance functions
used by core, when preparing new dataspaces. Thereby, it optimizes:

* on ARMv7 using per-word assignments
* on ARMv8 using cacheline zeroing
* on x86_64 using 'rept stosq' assembler instruction

Fix #3685
2020-03-11 15:43:02 +01:00
Stefan Kalkowski
065b9fdb46 base-hw: extend syscalls to five arguments
Ref #3553
2019-11-21 14:29:36 +01:00
Stefan Kalkowski
87015df66c hw: change update_pd to invalidate_tlb
In the past, the core-only privileged syscall `update_pd` was used only
to invalidate the TLB after removal of page-table entries.
By now, the whole TLB at least for one protection domain got invalidated,
but in preparation for optimization and upcomingARM v8 support,
it is necessary to deliver the virtual memory region that needs to get
invalidated. Moreover, the name of the call shall represent explicitely
that it is used to invalidate the TLB.

Ref #3405
2019-07-09 08:55:22 +02:00
Stefan Kalkowski
0ca199f89a hw: replace lock-safe log variants in kernel
As far as possible remove usage of warning/error/log in the kernel,
otherwise the kernel context might try to take a lock hold by a core
thread, which results in a syscall to block.

Fix #3277
2019-04-09 12:30:35 +02:00
Stefan Kalkowski
80fa23da5e hw: increase timing accuracy of kernel (fix #3081)
* Introduce 64-bit tick counter
* Let the timer always count when possible, also if it already fired
* Simplify the kernel syscall API to have one current time call,
  which returns the elapsed microseconds since boot
2019-03-18 15:56:23 +01:00
Stefan Kalkowski
2ecf1d887b hw: schedule on demand (Fix #3157) 2019-03-18 15:56:23 +01:00
Stefan Kalkowski
8e13b376b0 hw: improve cross-cpu synchronization
This commit addresses several multiprocessing issues in base-hw:

* it reworks cross-cpu maintainance work for TLB invalidation by
  introducing a generic Inter_processor_work and removes the so
  called Cpu_domain_update
* thereby it solves the cross-cpu thread destruction, when the
  corresponding thread is active on another cpu (fix #3043)
* it adds the missing TLB shootdown for x86 (fix #3042)
* on ARM it removes the TLB shootdown via IPIs, because this
  is not needed on the multiprocessing ARM platforms we support
* it enables the per-cpu initialization of the kernel's cpu
  objects, which means those object initialization is executed
  by the proper cpu
* it rollbacks prior decision to make multiprocessing an aspect,
  but puts back certain 'smp' mechanisms (like cross-cpu lock)
  into the generic code base for simplicity reasons
2019-01-07 12:25:44 +01:00
Stefan Kalkowski
be4e34b6b5 hw: unify mmu fault handling
Recent work related to issue 1723 showed that there is potential
to get rid of code duplication in MMU fault handling especially
with regard to ARM cpus.
2017-11-06 13:57:22 +01:00
Stefan Kalkowski
d6a05245f2 hw: remove User_context
Fix #2540
2017-11-06 13:57:20 +01:00
Stefan Kalkowski
0635d5fffb hw: turn Cpu_idle into a Thread
Fix #2539
2017-11-06 13:57:20 +01:00
Stefan Kalkowski
4e97a6511b hw: switch page-tables only when necessary
* Instead of always re-load page-tables when a thread context is switched
  only do this when another user PD's thread is the next target,
  core-threads are always executed within the last PD's page-table set
* remove the concept of the mode transition
* instead map the exception vector once in bootstrap code into kernel's
  memory segment
* when a new page directory is constructed for a user PD, copy over the
  top-level kernel segment entries on RISCV and X86, on ARM we use a designated
  page directory register for the kernel segment
* transfer the current CPU id from bootstrap to core/kernel in a register
  to ease first stack address calculation
* align cpu context member of threads and vms, because of x86 constraints
  regarding the stack-pointer loading
* introduce Align_at template for members with alignment constraints
* let the x86 hardware do part of the context saving in ISS, by passing
  the thread context into the TSS before leaving to user-land
* use one exception vector for all ARM platforms including Arm_v6

Fix #2091
2017-10-19 13:31:18 +02:00
Stefan Kalkowski
ca60e24ad9 hw: run core threads in privileged mode
* introduce new syscall (core-only) to create privileged threads
* take the privilege level of the thread into account
  when doing a context switch
* map kernel segment as accessable for privileged code only

Ref #2091
2017-10-19 13:31:17 +02:00
Sebastian Sumpf
e17accb3ba base-hw: RISC-V save/restore 'x29' correctly
* register x29/t4 was not saved and therefore not restored correctly
* change 'warning' to 'error' before '_die' is called

issue #2423
2017-08-30 09:59:59 +02:00
Stefan Kalkowski
96eb82574a hw: fix race in core's pager code (fix #2301)
* Acknowledge receive of page-fault signal with ack_signal,
  but restart thread execution separately
* use kill_signal_context when disolving a pager_object to prevent race
* Remove bureaucracy in form of Thread_event and Signal_ack_handler
* remove dead code in riscv, namely Thread_base definition
* translation_table_insertions function for ARM drops out,
  which was overcautious
2017-03-15 12:24:41 +01:00
Norman Feske
29b8d609c9 Adjust file headers to refer to the AGPLv3 2017-02-28 12:59:29 +01:00
Martin Stein
71d30297ff hw: clean up scheduling-readiness syscalls
This cleans up the syscalls that are mainly used to control the
scheduling readiness of a thread. The different use cases and
requirements were somehow mixed together in the previous interface. The
new syscall set is:

1) pause_thread and resume_thread

They don't affect the state of the thread (IPC, signalling, etc.) but
merely decide wether the thread is allowed for scheduling or not, the
so-called pause state. The pause state is orthogonal to the thread state
and masks it when it comes to scheduling. In contrast to the stopped
state, which is described in "stop_thread and restart_thread", the
thread state and the UTCB content of a thread may change while in the
paused state. However, the register state of a thread doesn't change
while paused. The "pause" and "resume" syscalls are both core-restricted
and may target any thread. They are used as back end for the CPU session
calls "pause" and "resume". The "pause/resume" feature is made for
applications like the GDB monitor that transparently want to stop and
continue the execution of a thread no matter what state the thread is
in.

2) stop_thread and restart_thread

The stop syscall can only be used on a thread in the non-blocking
("active") thread state. The thread then switches to the "stopped"
thread state in wich it explicitely waits for a restart. The restart
syscall can only be used on a thread in the "stopped" or the "active"
thread state. The thread then switches back to the "active" thread state
and the syscall returns whether the thread was stopped. Both syscalls
are not core-restricted. "Stop" always targets the calling thread while
"restart" may target any thread in the same PD as the caller. Thread
state and UTCB content of a thread don't change while in the stopped
state. The "stop/restart" feature is used when an active thread wants to
wait for an event that is not known to the kernel. Actually the syscalls
are used when waiting for locks and on thread exit.

3) cancel_thread_blocking

Does cleanly cancel a cancelable blocking thread state (IPC, signalling,
stopped). The thread whose blocking was cancelled goes back to the
"active" thread state. It may receive a syscall return value that
reflects the cancellation. This syscall doesn't affect the pause state
of the thread which means that it may still not get scheduled. The
syscall is core-restricted and may target any thread.

4) yield_thread

Does its best that a thread is scheduled as few as possible in the
current scheduling super-period without touching the thread or pause
state. In the next superperiod, however, the thread is scheduled
"normal" again. The syscall is not core-restricted and always targets
the caller.

Fixes #2104
2016-12-14 11:22:27 +01:00
Stefan Kalkowski
2a2e5c2df4 base-*: remove usage of printf
base generic code:
  * Remove unused verbosity code from mmio framework
  * Remove escape sequence end heuristic from LOG
  * replace Core_console with Core_log (no format specifiers)
  * move test/printf to test/log
  * remove `printf()` tests from the log test
  * check for exact match of the log test output
base-fiasco:
  * remove unused Fiasco::print_l4_threadid function
base-nova:
  * remove unused hexdump utility from core
base-hw:
  * remove unused Kernel::Thread::_print_* debug utilities
  * always print resource summary of core during startup
  * remove Kernel::Ipc_node::pd_label (not used anymore)
base*:
  * Turn `printf`,`PWRN`, etc. calls into their log equivalents

Ref #1987
Fix #2119
2016-10-21 12:39:36 +02:00
Sebastian Sumpf
d17134baef ldso: Support for RISC-V
issue #1880
2016-02-26 11:36:51 +01:00
Mark Vels
1668983efa base-hw: RISC-V Rocket Core on Zynq
This commit adds rocket core on the Zynq FPGA support to base HW. It also takes
advantage of the new timer infrastructure introduced with the privileged 1.8 and
adds improved TLB flush support.

fixes #1880
2016-02-26 11:36:51 +01:00
Sebastian Sumpf
c246a0d194 base-hw: initial RISC-V support
using the spike instruction emulator

issue #1880
2016-02-26 11:36:51 +01:00