Commit Graph

14 Commits

Author SHA1 Message Date
Andrew Boie
348d1315d2 x86: 32-bit: restore virtual linking capability
This reverts commit 7d32e9f9a5.

We now allow the kernel to be linked virtually. This patch:

- Properly converts between virtual/physical addresses
- Handles early boot instruction pointer transition
- Double-maps SRAM to both virtual and physical locations
  in boot page tables to facilitate instruction pointer
  transition, with logic to clean this up after completed.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
2021-03-16 15:03:44 -04:00
Daniel Leung
dd98de880a x86: move calling z_loapic_enable into z_x86_prep_c
This moves calling z_loapic_enable() from crt0.S into
z_x86_prep_c(). This is done so we can move BSS clearing
and data section copying inside z_x86_prep_c() as
these are needed before calling z_loapic_enable().

Signed-off-by: Daniel Leung <daniel.leung@intel.com>
2021-02-21 22:28:33 -05:00
Andrew Boie
7d32e9f9a5 mmu: support only identity RAM mapping
We no longer plan to support a split address space with
the kernel in high memory and per-process address spaces.
Because of this, we can simplify some things. System RAM
is now always identity mapped at boot.

We no longer require any virtual-to-physical translation
for page tables, and can remove the dual-mapping logic
from the page table generation script since we won't need
to transition the instruction point off of physical
addresses.

CONFIG_KERNEL_VM_BASE and CONFIG_KERNEL_VM_LIMIT
have been removed. The kernel's address space always
starts at CONFIG_SRAM_BASE_ADDRESS, of a fixed size
specified by CONFIG_KERNEL_VM_SIZE.

Driver MMIOs and other uses of k_mem_map() are still
virtually mapped, and the later introduction of demand
paging will result in only a subset of system RAM being
a fixed identity mapping instead of all of it.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2020-09-03 14:24:38 -04:00
Andrew Boie
38e17b68e3 x86: paging code rewrite
The x86 paging code has been rewritten to support another paging mode
and non-identity virtual mappings.

 - Paging code now uses an array of paging level characteristics and
   walks tables using for loops. This is opposed to having different
   functions for every paging level and lots of #ifdefs. The code is
   now more concise and adding new paging modes should be trivial.

 - We now support 32-bit, PAE, and IA-32e page tables.

 - The page tables created by gen_mmu.py are now installed at early
   boot. There are no longer separate "flat" page tables. These tables
   are mutable at any time.

 - The x86_mmu code now has a private header. Many definitions that did
   not need to be in public scope have been moved out of mmustructs.h
   and either placed in the C file or in the private header.

 - Improvements to dumping page table information, with the physical
   mapping and flags all shown

 - arch_mem_map() implemented

 - x86 userspace/memory domain code ported to use the new
   infrastructure.

 - add logic for physical -> virtual instruction pointer transition,
   including cleaning up identity mappings after this takes place.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2020-08-25 15:49:59 -04:00
Andrew Boie
8ce260d8df kernel: introduce supervisor-only stacks
These stacks are appropriate for threads that run purely in
supervisor mode, and also as stacks for interrupt and exception
handling.

Two new arch defines are introduced:

- ARCH_KERNEL_STACK_GUARD_SIZE
- ARCH_KERNEL_STACK_OBJ_ALIGN

New public declaration macros:

- K_KERNEL_STACK_RESERVED
- K_KERNEL_STACK_EXTERN
- K_KERNEL_STACK_DEFINE
- K_KERNEL_STACK_ARRAY_DEFINE
- K_KERNEL_STACK_MEMBER
- K_KERNEL_STACK_SIZEOF

If user mode is not enabled, K_KERNEL_STACK_* and K_THREAD_STACK_*
are equivalent.

Separately generated privilege elevation stacks are now declared
like kernel stacks, removing the need for K_PRIVILEGE_STACK_ALIGN.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2020-07-30 21:11:14 -04:00
Andy Ross
c7d76cbe58 arch/x86: Add a spurious interrupt handler to x86_64
Right now x86_64 doesn't install handlers for vectors that aren't
populated by Zephyr code.  Add a tiny spurious interrupt handler that
logs the error and triggers a fatal error, like other platforms do.

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2020-07-08 12:34:09 +02:00
Andy Ross
7fe8caebc0 arch/x86: Add z_acpi_find_table(), MCFG support
The existing minimal ACPI implementation was enough to find the MADT
table for dumping CPU info.  Enhance it with a slightly less minimal
implementation that can fetch any table, supports the ACPI 2.0 XSDT
directory (technically required on 64 bit systems so tables can live
>4G) and provides definitions for the MCFG table with the PCI
configuration pointers.

Note that there is no use case right now for high performance table
searching, so the "init" step has been removed and tables are probed
independently from scratch for each one requested (there are only
two).

Note also that the memory to which these tables point is not
understood by the Zephyr MMU configuration, so in long mode all ACPI
calls have to be done very early, before z_x86_paging_init() (or on a
build with the MMU initialization disabled).

Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2020-06-23 13:07:39 +02:00
Andrew Boie
80a0d9d16b kernel: interrupt/idle stacks/threads as array
The set of interrupt stacks is now expressed as an array. We
also define the idle threads and their associated stacks this
way. This allows for iteration in cases where we have multiple
CPUs.

There is now a centralized declaration in kernel_internal.h.

On uniprocessor systems, z_interrupt_stacks has one element
and can be used in the same way as _interrupt_stack.

The IRQ stack for CPU 0 is now set in init.c instead of in
arch code.

The extern definition of the main thread stack is now removed,
this doesn't need to be in a header.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2020-03-16 23:17:36 +02:00
Andrew Boie
a594ca7c8f kernel: cleanup and formally define CPU start fn
The "key" parameter is legacy, remove it.

Add a typedef for the expected function pointer type.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2020-01-13 16:35:10 -05:00
Stephanos Ioannidis
2d7460482d headers: Refactor kernel and arch headers.
This commit refactors kernel and arch headers to establish a boundary
between private and public interface headers.

The refactoring strategy used in this commit is detailed in the issue

This commit introduces the following major changes:

1. Establish a clear boundary between private and public headers by
  removing "kernel/include" and "arch/*/include" from the global
  include paths. Ideally, only kernel/ and arch/*/ source files should
  reference the headers in these directories. If these headers must be
  used by a component, these include paths shall be manually added to
  the CMakeLists.txt file of the component. This is intended to
  discourage applications from including private kernel and arch
  headers either knowingly and unknowingly.

  - kernel/include/ (PRIVATE)
    This directory contains the private headers that provide private
   kernel definitions which should not be visible outside the kernel
   and arch source code. All public kernel definitions must be added
   to an appropriate header located under include/.

  - arch/*/include/ (PRIVATE)
    This directory contains the private headers that provide private
   architecture-specific definitions which should not be visible
   outside the arch and kernel source code. All public architecture-
   specific definitions must be added to an appropriate header located
   under include/arch/*/.

  - include/ AND include/sys/ (PUBLIC)
    This directory contains the public headers that provide public
   kernel definitions which can be referenced by both kernel and
   application code.

  - include/arch/*/ (PUBLIC)
    This directory contains the public headers that provide public
   architecture-specific definitions which can be referenced by both
   kernel and application code.

2. Split arch_interface.h into "kernel-to-arch interface" and "public
  arch interface" divisions.

  - kernel/include/kernel_arch_interface.h
    * provides private "kernel-to-arch interface" definition.
    * includes arch/*/include/kernel_arch_func.h to ensure that the
     interface function implementations are always available.
    * includes sys/arch_interface.h so that public arch interface
     definitions are automatically included when including this file.

  - arch/*/include/kernel_arch_func.h
    * provides architecture-specific "kernel-to-arch interface"
     implementation.
    * only the functions that will be used in kernel and arch source
     files are defined here.

  - include/sys/arch_interface.h
    * provides "public arch interface" definition.
    * includes include/arch/arch_inlines.h to ensure that the
     architecture-specific public inline interface function
     implementations are always available.

  - include/arch/arch_inlines.h
    * includes architecture-specific arch_inlines.h in
     include/arch/*/arch_inline.h.

  - include/arch/*/arch_inline.h
    * provides architecture-specific "public arch interface" inline
     function implementation.
    * supersedes include/sys/arch_inline.h.

3. Refactor kernel and the existing architecture implementations.

  - Remove circular dependency of kernel and arch headers. The
   following general rules should be observed:

    * Never include any private headers from public headers
    * Never include kernel_internal.h in kernel_arch_data.h
    * Always include kernel_arch_data.h from kernel_arch_func.h
    * Never include kernel.h from kernel_struct.h either directly or
     indirectly. Only add the kernel structures that must be referenced
     from public arch headers in this file.

  - Relocate syscall_handler.h to include/ so it can be used in the
   public code. This is necessary because many user-mode public codes
   reference the functions defined in this header.

  - Relocate kernel_arch_thread.h to include/arch/*/thread.h. This is
   necessary to provide architecture-specific thread definition for
   'struct k_thread' in kernel.h.

  - Remove any private header dependencies from public headers using
   the following methods:

    * If dependency is not required, simply omit
    * If dependency is required,
      - Relocate a portion of the required dependencies from the
       private header to an appropriate public header OR
      - Relocate the required private header to make it public.

This commit supersedes #20047, addresses #19666, and fixes #3056.

Signed-off-by: Stephanos Ioannidis <root@stephanos.io>
2019-11-06 16:07:32 -08:00
Andrew Boie
31620b90e2 x86: refactor mmustructs.h
The struct definitions for pdpt, pd, and pt entries has been
removed:

 - Bitfield ordering in a struct is implementation dependent,
   it can be right-to-left or left-to-right
 - The two different structures for page directory entries were
   not being used consistently, or when the type of the PDE
   was unknown
 - Anonymous structs/unions are GCC extensions

Instead these are now u64_t, with bitwise operations used to
get/set fields.

A new set of inline functions for fetcing various page table
structures has been implemented, replacing the older macros.

Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2019-10-14 11:49:39 -07:00
Charles E. Youse
66510db98c arch/x86: (Intel64) add scheduler IPI support
Add z_arch_sched_ipi() and such to enable scheduler IPIs when SMP.

Signed-off-by: Charles E. Youse <charles.youse@intel.com>
2019-10-07 19:46:55 -04:00
Charles E. Youse
2808908816 arch/x86: alter signature of z_x86_prep_c() function
Take a dummy first argument, so that the BSP entry point (z_x86_prep_c)
has the same signature as the AP entry point (smp_init_top).

Signed-off-by: Charles E. Youse <charles.youse@intel.com>
2019-10-07 19:46:55 -04:00
Charles E. Youse
8279af76c8 arch/x86: elevate prep_c.c to common code
Elevate the previously 32-bit-only z_x86_prep_c() function to common
code, so both 32-bit and 64-bit arches now enter the kernel this way.
Minor changes to prep_c.c to make it build with the SMP scheduler on.

Signed-off-by: Charles E. Youse <charles.youse@intel.com>
2019-10-07 19:46:55 -04:00