Commit Graph

22 Commits

Author SHA1 Message Date
Andrew Boie 7f82b99ad4 x86: up-level some user mode functions
These are now common code, all are related to user mode
threads. The rat's nest of ifdefs in ia32's arch_new_thread
has been greatly simplified, there is now just one hook
if user mode is turned on.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2020-01-13 16:35:10 -05:00
Andrew Boie 7ea958e0dd x86: optimize locations of psp and thread ptables
z_x86_thread_page_tables_get() now works for both user
and supervisor threads, returning the kernel page tables
in the latter case. This API has been up-leveled to
a common header.

The per-thread privilege elevation stack initial stack
pointer, and the per-thread page table locations are no
longer computed from other values, and instead are stored
in thread->arch.

A problem where the wrong page tables were dumped out
on certain kinds of page faults has been fixed.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2020-01-13 16:35:10 -05:00
Andrew Boie 4f77c2ad53 kernel: rename z_arch_ to arch_
Promote the private z_arch_* namespace, which specifies
the interface between the core kernel and the
architecture code, to a new top-level namespace named
arch_*.

This allows our documentation generation to create
online documentation for this set of interfaces,
and this set of interfaces is worth treating in a
more formal way anyway.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2019-11-07 15:21:46 -08:00
Andrew Boie 64f6e2ac6b x86: consolidate STACK_ROUND_* definition
There was no definition for 64-bit.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2019-11-06 17:50:34 -08:00
Andrew Boie f6e82ea1bd x86: generate runtime 64-bit page tables
- Bring in CONFIG_X86_MMU and some related defines to
  common X86 Kconfig
- Don't set ARCH_HAS_USERSPACE for intel64 yet when
  X86_MMU is enabled
- Uplevel x86_mmu.c to common code
- Add logic for handling PML4 table and generating PDPTs
- move z_x86_paging_init() to common kernel_arch_func.h
- Uplevel inclusion of mmustructs.h to common x86 arch.h,
  both need it for memory domain defines

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2019-10-24 12:48:45 -07:00
Andrew Boie 24958f30d9 x86: move z_x86_early_serial_init()
This works with long mode as well, uplevel to
common kernel_arch_func.h.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2019-10-15 09:00:49 -07:00
Andrew Boie 8ffff144ea kernel: add architecture interface headers
include/sys/arch_inlines.h will contain all architecture APIs
that are used by public inline functions and macros,
with implementations deriving from include/arch/cpu.h.

kernel/include/arch_interface.h will contain everything
else, with implementations deriving from
arch/*/include/kernel_arch_func.h.

Instances of duplicate documentation for these APIs have been
removed; implementation details have been left in place.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2019-10-11 13:30:46 -07:00
Andrew Boie f0ddbd7eee x86: abstract toplevel page table pointer
This patch is a preparatory step in enabling the MMU in
long mode; no steps are taken to implement long mode support.

We introduce struct x86_page_tables, which represents the
top-level data structure for page tables:

- For 32-bit, this will contain a four-entry page directory
  pointer table (PDPT)
- For 64-bit, this will (eventually) contain a page map level 4
  table (PML4)

In either case, this pointer value is what gets programmed into
CR3 to activate a set of page tables. There are extra bits in
CR3 to set for long mode, we'll get around to that later.

This abstraction will allow us to use the same APIs that work
with page tables in either mode, rather than hard-coding that
the top level data structure is a PDPT.

z_x86_mmu_validate() has been re-written to make it easier to
add another level of paging for long mode, to support 2MB
PDPT entries, and correctly validate regions which span PDPTE
entries.

Some MMU-related APIs moved out of 32-bit x86's arch.h into
mmustructs.h.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2019-10-04 15:53:49 -07:00
Andrew Boie f6fb634b89 kernel: rename kernel_arch_init()
This is part of the core kernel -> architecture interface and
has been renamed z_arch_kernel_init().

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2019-09-30 15:25:55 -04:00
Andrew Boie 4ad9f687df kernel: rename thread return value functions
z_set_thread_return_value is part of the core kernel -> arch
interface and has been renamed to z_arch_thread_return_value_set.

z_set_thread_return_value_with_data renamed to
z_thread_return_value_set_with_data for consistency.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2019-09-30 15:25:55 -04:00
Andrew Boie 07525a3d54 kernel: add arch interface for idle functions
k_cpu_idle() and k_cpu_atomic_idle() were being directly
implemented by arch code.

Rename these implementations to z_arch_cpu_idle() and
z_arch_cpu_atomic_idle(), and call them from new inline
function definitions in kernel.h.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2019-09-30 15:25:55 -04:00
Charles E. Youse a1afde043c arch/x86: share declaration of _interrupt_stack
This is moved from arch/x86/include/ia32/kernel_arch_func.h to the
common header arch/x86/include/kernel_arch_func.h so it can be shared.

Signed-off-by: Charles E. Youse <charles.youse@intel.com>
2019-09-23 17:50:09 -07:00
Charles E. Youse 4ddaa59a89 arch/x86: initial Intel64 support
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>
2019-09-15 11:33:47 +08:00
Peter Bigot 324203f79b arch/x86: rearrange for standard use of extern "C"
Consistently place C++ use of extern "C" after all include directives,
within the negative branch of _ASMLANGUAGE if used.

Background from issue #17997:

Declarations that use C linkage should be placed within extern "C"
so the language linkage is correct when the header is included by
a C++ compiler.

Similarly #include directives should be outside the extern "C" to
ensure the language-specific default linkage is applied to any
declarations provided by the included header.

See: https://en.cppreference.com/w/cpp/language/language_linkage
Signed-off-by: Peter Bigot <peter.bigot@nordicsemi.no>
2019-08-20 00:49:15 +02:00
Andrew Boie 02629b69b5 x86: add prep_c function
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>
2019-08-07 12:50:53 -07:00
Andrew Boie c3b3aafaec x86: generate page tables at runtime
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>
2019-08-07 12:50:53 -07:00
Andrew Boie 0add92523c x86: use a struct to specify stack layout
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>
2019-08-05 13:25:50 +02:00
Andrew Boie 8014e075f4 x86: use per-thread page tables
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>
2019-08-05 13:25:50 +02:00
Andrew Boie 8915e41b7b userspace: adjust arch memory domain interface
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>
2019-08-05 13:25:50 +02:00
Andrew Boie 76310f6896 x86: make guard pages ro instead of non-present
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>
2019-08-05 13:25:50 +02:00
Andrew Boie bd709c7322 x86: support very early printk() if desired
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>
2019-08-02 00:29:21 -07:00
Charles E. Youse 820ea28f87 arch/x86: move kernel_arch_func.h to ia32/
Refactoring 32- and 64-bit subarchitectures, so this file is moved
to ia32/ and a new "redirector" header file is introduced.

Signed-off-by: Charles E. Youse <charles.youse@intel.com>
2019-07-03 20:01:17 -04:00