The interface to flush fpu is not unique to one architecture, make it a
generic, optional interface that can be implemented (and overriden) by a
platform.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
The z_arm64_fatal_error should be
extern void z_arm64_fatal_error(unsigned int reason, z_arch_esf_t *esf);
Signed-off-by: Jaxson Han <jaxson.han@arm.com>
Add safe exception stack init function which does several things:
1) setting current cpu safe exception stack pointer to its corresponding
stack top.
2) init sp_el0 with the above safe exception stack.
That makes sure the sp_el0 points to per-cpu safe_stack in the kernel
space.
3) init the current_stack_limit and corrupted_sp with 0
Signed-off-by: Jaxson Han <jaxson.han@arm.com>
Add three per-cpu variables for the convenience of quickly accessing.
The safe_exception_stack stores the top of safe exception stack pointer.
The current_stack_limit stores the current thread's priv stack limit.
The corrputed_sp stores the priv sp or irq sp for the stack overflow
case, or 0 for the normal case.
Signed-off-by: Jaxson Han <jaxson.han@arm.com>
In order to bring consistency in-tree, migrate all arch code to the new
prefix <zephyr/...>. Note that the conversion has been scripted, refer
to zephyrproject-rtos#45388 for more details.
Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
It is not necessary to go through the full exception exit code.
This is simpler, smaller and faster.
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
Make it optimal without the need for an SVC/exception roundtrip on
every context switch. Performance numbers from tests/benchmarks/sched:
Before:
unpend 85 ready 58 switch 258 pend 231 tot 632 (avg 699)
After:
unpend 85 ready 59 switch 115 pend 138 tot 397 (avg 478)
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
Get rid of all those global variables and scheduler locking.
Use the reguler IRQ exit path to let tests properly validate preemption.
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
Include the new introduced include/arch/arm64/mm.h instead of the
arm_mmu.h or arm_mpu.h.
Unify function names z_arm64_thread_pt_init/z_arm64_swap_ptables with
z_arm64_thread_mem_domains_init/z_arm64_swap_mem_domains for mmu and
mpu, because:
1. mmu and mpu have almost the same logic.
2. mpu doesn't have ptables.
3. using the function names help reducing "#if define" macros.
Similarly, change z_arm64_ptable_ipi to z_arm64_domain_sync_ipi
And fix a log bug in arm_mmu.c.
Signed-off-by: Jaxson Han <jaxson.han@arm.com>
We can use build-time offsets from a struct k_thread pointer directly
to struct _callee_saved members. No need to compute that at run time.
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
This adds FPU sharing support with a lazy context switching algorithm.
Every thread is allowed to use FPU/SIMD registers. In fact, the compiler
may insert FPU reg accesses in anycontext to optimize even non-FP code
unless the -mgeneral-regs-only compiler flag is used, but Zephyr
currently doesn't support such a build.
It is therefore possible to do FP access in IRS as well with this patch
although IRQs are then disabled to prevent nested IRQs in such cases.
Because the thread object grows in size, some tests have to be adjusted.
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
Add the exception depth count to tpidrro_el0 and make it available
through the arch_exception_depth() accessor.
The IN_EL0 flag is now updated unconditionally even if userspace is
not configured. Doing otherwise made the code rather hairy and
I doubt the overhead is measurable.
Signed-off-by: Nicolas Pitre <npitre@baylibre.com>
The ARM64 port is currently using SP_EL0 for everything: kernel threads,
user threads and exceptions. In addition when taking an exception the
exception code is still using the thread SP without relying on any
interrupt stack.
If from one hand this makes the context switch really quick because the
thread context is already on the thread stack so we have only to save
one register (SP) for the whole context, on the other hand the major
limitation introduced by this choice is that if for some reason the
thread SP is corrupted or pointing to some unaccessible location (for
example in case of stack overflow), the exception code is unable to
recover or even deal with it.
The usual way of dealing with this kind of problems is to use a
dedicated interrupt stack on SP_EL1 when servicing the exceptions. The
real drawback of this is that, in case of context switch, all the
context must be copied from the shared interrupt stack into a
thread-specific stack or structure, so it is really slow.
We use here an hybrid approach, sacrificing a bit of stack space for a
quicker context switch. While nothing really changes for kernel threads,
for user threads we now use the privileged stack (already present to
service syscalls) as interrupt stack.
When an exception arrives the code now switches to use SP_EL1 that for
user threads is always pointing inside the privileged portion of the
stack of the current running thread. This achieves two things: (1)
isolate exceptions and syscall code to use a stack that is isolated,
privileged and not accessible to user threads and (2) the thread SP is
not touched at all during exceptions, so it can be invalid or corrupted
without any direct consequence.
Signed-off-by: Carlo Caione <ccaione@baylibre.com>
Split ARM and ARM64 architectures.
Details:
- CONFIG_ARM64 is decoupled from CONFIG_ARM (not a subset anymore)
- Arch and include AArch64 files are in a dedicated directory
(arch/arm64 and include/arch/arm64)
- AArch64 boards and SoC are moved to soc/arm64 and boards/arm64
- AArch64-specific DTS files are moved to dts/arm64
- The A72 support for the bcm_vk/viper board is moved in the
boards/bcm_vk/viper directory
Signed-off-by: Carlo Caione <ccaione@baylibre.com>
