This used to be part of the "restore always" set of registers because
__swap was expected to return a value. No longer required, so RAX is
moved to the volatile registers and we save a few cycles occasionally.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
A space is allocated in the TSS for per-CPU variables. At present,
this is only a 'struct _cpu *' to find the _kernel CPU struct. The
locore routines are rewritten to find _current and _nested via this
pointer rather than referencing the _kernel global directly.
This is obviously in preparation for SMP support.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
This function call was erroneously inserted between the instruction
that set the Z flag and the instruction that tested the Z flag. The
call is moved up a few instructions where it can't junk CPU state.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
Declare the 64-bit TSS as a struct, and define the instance in C.
Add a data segment selector that overlaps the TSS and keep that
loaded in GS so we can access the TSS via a segment-override prefix.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
This is largely a conceptual change rather than an actual change.
Instead of using an array of interrupt stacks (one for each IRQ
nesting level), we use one interrupt stack and subdivide it. The
effect is the same, but this is more in line with the Zephyr model
of one ISR stack per CPU (as reflected in init.c).
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
Like its 32-bit sibling, the 64-bit code should EOI inline rather than
invoking a function. Defeats the performance advantages of x2APIC.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
The boot time measurement sample was giving bogus values on x86: an
assumption was made that the system timer is in sync with the CPU TSC,
which is not the case on most x86 boards.
Boot time measurements are no longer permitted unless the timer source
is the local APIC. To avoid issues of TSC scaling, the startup datum
has been forced to 0, which is in line with the ARM implementation
(which is the only other platform which supports this feature).
Cleanups along the way:
As the datum is now assumed zero, some variables are removed and
calculations simplified. The global variables involved in boot time
measurements are moved to the kernel.h header rather than being
redeclared in every place they are referenced. Since none of the
measurements actually use 64-bit precision, the samples are reduced
to 32-bit quantities.
In addition, this feature has been enabled in long mode.
Fixes: #19144
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
There are not enough bits in k_thread.thread_state with SMP enabled,
and the field is (should be) private to the scheduler, anyway. So
move state bits to the _thread_arch where they belong.
While we're at it, refactor some offset data w/r/t _thread_arch
because it can be shared between 32- and 64-bit subarches.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
k_thread.thread_state (or rather, _thread_base.thread_state) should be
private to the kernel/scheduler, so flags previously stored there are
moved to _thread_arch where the belong.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
We don't need to save the ABI caller-save registers here, because
we don't preempt threads from nested IRQ contexts.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
This is a naive implementation which does "eager" context switching
for floating-point context, which, of course, introduces performance
concerns. Other approaches have security concerns, SMP implications,
and impact the x86 arch and Zephyr project as a whole. Discussion is
needed, so punting with the straightforward solution for now.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
Fleshed out z_arch_esf_t and added code to build this frame when
exceptions occur. Created a separate small stack for exceptions and
shifted the initialization code to use this instead of the IRQ stack.
Moved IRQ stack(s) to irq.c.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
The IRQ_OFFLOAD_VECTOR config option is also moved to the arch level,
as it is shared between both 32- and 64-bit subarches.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
Using the arch Kconfig here, instead of kernel/Kconfig. Intel64 with
the SysV ABI requires some pretty big stacks. These 4K-8K defaults
are arguably a bit small, but the Zephyr defaults are REALLY too small.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
First "complete" version of Intel64 support for x86. Compilation of
apps for supported boards (read: up_squared) with CONFIG_X86_LONGMODE=y
is now working. Booting, device drivers, interrupts, scheduling, etc.
appear to be functioning properly. Beware that this is ALHPA quality,
not ready for production use, but the port has advanced far enough that
it's time to start working through the test suite and samples, fleshing
out any missing features, and squashing bugs.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
Widen the integer to pointer size before conversion, to make
explicit the intent (and silence the compiler warning). Also
fix a minor bug involving a duplicate (and thus dead) store.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
This patch adds basic build infrastructure, definitions, a linker
script, etc. to use the Zephyr and 0.10.1 SDK to build a 64-bit
ELF binary suitable for use with GRUB to minimally bootstrap an
Apollo Lake (e.g., UpSquared) board. The resulting binary can hardly
be called a Zephyr kernel as it is lacking most of the glue logic,
but it is a starting point to flesh those out in the x86 tree.
The "kernel" builds with a few harmless warnings, both with GCC from
the Zephyr SDK and with ICC (which is currently being worked on in
a separate branch). These warnings are either related to pointer size
differences (since this is an LP64 build) and/or dummy functions
that will be replaced with working versions shortly.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
The IA32 and Intel64 subarchitectures will generate different offset
symbols, so they are refactored. No functional change.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
The _irq_to_interrupt_vector[] array shouldn't be accessed directly,
as there is a macro for this.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
From the Jailhouse days, this has been a function call. That's silly.
We now inline the EOI in the ISR when in x2APIC mode. Also clean up
z_irq_controller_eoi(), so it now uses the inline macros.
Also, we now enable x2APIC on up_squared by default.
Fixes: #17133
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
Assembly language start code will enter here, which sets up
early kernel initialization and then calls z_cstart() when
finished.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Removes very complex boot-time generation of page tables
with a much simpler runtime generation of them at bootup.
For those x86 boards that enable the MMU in the defconfig,
set the number of page pool pages appropriately.
The MMU_RUNTIME_* flags have been removed. They were an
artifact of the old page table generation and did not
correspond to any hardware state.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Makes the code that defines stacks, and code referencing
areas within the stack object, much clearer.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Previously, context switching on x86 with memory protection
enabled involved walking the page tables, de-configuring all
the partitions in the outgoing thread's memory domain, and
then configuring all the partitions in the incoming thread's
domain, on a global set of page tables.
We now have a much faster design. Each thread has reserved in
its stack object a number of pages to store page directories
and page tables pertaining to the system RAM area. Each
thread also has a toplevel PDPT which is configured to use
the per-thread tables for system RAM, and the global tables
for the rest of the address space.
The result of this is on context switch, at most we just have
to update the CR3 register to the incoming thread's PDPT.
The x86_mmu_api test was making too many assumptions and has
been adjusted to work with the new design.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
The current API was assuming too much, in that it expected that
arch-specific memory domain configuration is only maintained
in some global area, and updates to domains that are not currently
active have no effect.
This was true when all memory domain state was tracked in page
tables or MPU registers, but no longer works when arch-specific
memory management information is stored in thread-specific areas.
This is needed for: #13441#13074#15135
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
These turned out to be quite useful when debugging MMU
issues, commit them to the tree. The output format is
virtually the same as gen_mmu_x86.py's verbose output.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Currently page tables have to be re-computed in
an expensive operation on context switch. Here we
reserve some room in the page tables such that
we can have per-thread page table data, which will
be much simpler to update on context switch at
the expense of memory.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Has the same effect of catching stack overflows, but
makes debugging with GDB simpler since we won't get
errors when inspecting such regions. Making these
areas non-present was more than we needed, read-only
is sufficient.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Adapted from similar code in the x86_64 port.
Useful when debugging boot problems on actual x86
hardware if a JTAG isn't handy or feasible.
Turn this on for qemu_x86.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
It looks like, at some point in the past, initializing thread stacks
was the responsibility of the arch layer. After that was centralized,
we forgot to remove the related conditional header inclusion. Fixed.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
This is now called z_arch_esf_t, conforming to our naming
convention.
This needs to remain a typedef due to how our offset generation
header mechanism works.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
We introduce a new z_fatal_print() API and replace all
occurrences of exception handling code to use it.
This routes messages to the logging subsystem if enabled.
Otherwise, messages are sent to printk().
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
* z_NanoFatalErrorHandler() is now moved to common kernel code
and renamed z_fatal_error(). Arches dump arch-specific info
before calling.
* z_SysFatalErrorHandler() is now moved to common kernel code
and renamed k_sys_fatal_error_handler(). It is now much simpler;
the default policy is simply to lock interrupts and halt the system.
If an implementation of this function returns, then the currently
running thread is aborted.
* New arch-specific APIs introduced:
- z_arch_system_halt() simply powers off or halts the system.
* We now have a standard set of fatal exception reason codes,
namespaced under K_ERR_*
* CONFIG_SIMPLE_FATAL_ERROR_HANDLER deleted
* LOG_PANIC() calls moved to k_sys_fatal_error_handler()
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Before, attempting to induce a kernel oops would instead
lead to a general protection fault as the interrupt vector
was at DPL=0.
Now we allow by setting DPL=3. We restrict the allowable
reason codes to either stack overflows or kernel oops; we
don't want user mode to be able to create a kernel panic,
or fake some other kind of exception.
Fixes an issue where the stack canary test case was triggering
a GPF instead of a stack check exception on x86.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
For the x86 architecture the z_arch_float_disable() is only
implemented when building with CONFIG_LAZY_FP_SHARING, so we
make z_arch_float_disable() return -ENOSYS when we build with
FLOAT and FP_SHARING but on an x86 platform where
LAZY_FP_SHARING is not supported.
Signed-off-by: Ioannis Glaropoulos <Ioannis.Glaropoulos@nordicsemi.no>
This file merely declares external functions referenced only
by ia32/cache.c, so the declarations are inlined instead.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
