This allows the SoC to specify some additional linker script
fragments into the bss, data and read-only data sections.
For example, the Cypress PSOC6 has a few input sections that
must be put into bss and data sections. Without specifying
these in the linker script, they are consider orphan sections
and the placement is based on linker heuristic which is
arbitrary.
POSIX is not supported as the main linker script is
provided by the host system's binutils and we have no control
over it. Also, currently Xtensa SoCs have their own linker
scripts so there is no need to this feature.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
If MMU is enabled, always make the BSS section MMU page aligned.
According to the comments, it is always aligned anyway.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
When building the real mode, the linker definition has to place
the real mode entry code at the start of flash area.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Summary: revised attempt at addressing issue 6290. The
following provides an alternative to using
CONFIG_APPLICATION_MEMORY by compartmentalizing data into
Memory Domains. Dependent on MPU limitations, supports
compartmentalized Memory Domains for 1...N logical
applications. This is considered an initial attempt at
designing flexible compartmentalized Memory Domains for
multiple logical applications and, with the provided python
script and edited CMakeLists.txt, provides support for power
of 2 aligned MPU architectures.
Overview: The current patch uses qualifiers to group data into
subsections. The qualifier usage allows for dynamic subsection
creation and affords the developer a large amount of flexibility
in the grouping, naming, and size of the resulting partitions and
domains that are built on these subsections. By additional macro
calls, functions are created that help calculate the size,
address, and permissions for the subsections and enable the
developer to control application data in specified partitions and
memory domains.
Background: Initial attempts focused on creating a single
section in the linker script that then contained internally
grouped variables/data to allow MPU/MMU alignment and protection.
This did not provide additional functionality beyond
CONFIG_APPLICATION_MEMORY as we were unable to reliably group
data or determine their grouping via exported linker symbols.
Thus, the resulting decision was made to dynamically create
subsections using the current qualifier method. An attempt to
group the data by object file was tested, but found that this
broke applications such as ztest where two object files are
created: ztest and main. This also creates an issue of grouping
the two object files together in the same memory domain while
also allowing for compartmenting other data among threads.
Because it is not possible to know a) the name of the partition
and thus the symbol in the linker, b) the size of all the data
in the subsection, nor c) the overall number of partitions
created by the developer, it was not feasible to align the
subsections at compile time without using dynamically generated
linker script for MPU architectures requiring power of 2
alignment.
In order to provide support for MPU architectures that require a
power of 2 alignment, a python script is run at build prior to
when linker_priv_stacks.cmd is generated. This script scans the
built object files for all possible partitions and the names given
to them. It then generates a linker file (app_smem.ld) that is
included in the main linker.ld file. This app_smem.ld allows the
compiler and linker to then create each subsection and align to
the next power of 2.
Usage:
- Requires: app_memory/app_memdomain.h .
- _app_dmem(id) marks a variable to be placed into a data
section for memory partition id.
- _app_bmem(id) marks a variable to be placed into a bss
section for memory partition id.
- These are seen in the linker.map as "data_smem_id" and
"data_smem_idb".
- To create a k_mem_partition, call the macro
app_mem_partition(part0) where "part0" is the name then used to
refer to that partition. This macro only creates a function and
necessary data structures for the later "initialization".
- To create a memory domain for the partition, the macro
app_mem_domain(dom0) is called where "dom0" is the name then
used for the memory domain.
- To initialize the partition (effectively adding the partition
to a linked list), init_part_part0() is called. This is followed
by init_app_memory(), which walks all partitions in the linked
list and calculates the sizes for each partition.
- Once the partition is initialized, the domain can be
initialized with init_domain_dom0(part0) which initializes the
domain with partition part0.
- After the domain has been initialized, the current thread
can be added using add_thread_dom0(k_current_get()).
- The code used in ztests ans kernel/init has been added under
a conditional #ifdef to isolate the code from other tests.
The userspace test CMakeLists.txt file has commands to insert
the CONFIG_APP_SHARED_MEM definition into the required build
targets.
Example:
/* create partition at top of file outside functions */
app_mem_partition(part0);
/* create domain */
app_mem_domain(dom0);
_app_dmem(dom0) int var1;
_app_bmem(dom0) static volatile int var2;
int main()
{
init_part_part0();
init_app_memory();
init_domain_dom0(part0);
add_thread_dom0(k_current_get());
...
}
- If multiple partitions are being created, a variadic
preprocessor macro can be used as provided in
app_macro_support.h:
FOR_EACH(app_mem_partition, part0, part1, part2);
or, for multiple domains, similarly:
FOR_EACH(app_mem_domain, dom0, dom1);
Similarly, the init_part_* can also be used in the macro:
FOR_EACH(init_part, part0, part1, part2);
Testing:
- This has been successfully tested on qemu_x86 and the
ARM frdm_k64f board. It compiles and builds power of 2
aligned subsections for the linker script on the 96b_carbon
boards. These power of 2 alignments have been checked by
hand and are viewable in the zephyr.map file that is
produced during build. However, due to a shortage of
available MPU regions on the 96b_carbon board, we are unable
to test this.
- When run on the 96b_carbon board, the test suite will
enter execution, but each individaul test will fail due to
an MPU FAULT. This is expected as the required number of
MPU regions exceeds the number allowed due to the static
allocation. As the MPU driver does not detect this issue,
the fault occurs because the data being accessed has been
placed outside the active MPU region.
- This now compiles successfully for the ARC boards
em_starterkit_em7d and em_starterkit_em7d_v22. However,
as we lack ARC hardware to run this build on, we are unable
to test this build.
Current known issues:
1) While the script and edited CMakeLists.txt creates the
ability to align to the next power of 2, this does not
address the shortage of available MPU regions on certain
devices (e.g. 96b_carbon). In testing the APB and PPB
regions were commented out.
2) checkpatch.pl lists several issues regarding the
following:
a) Complex macros. The FOR_EACH macros as defined in
app_macro_support.h are listed as complex macros needing
parentheses. Adding parentheses breaks their
functionality, and we have otherwise been unable to
resolve the reported error.
b) __aligned() preferred. The _app_dmem_pad() and
_app_bmem_pad() macros give warnings that __aligned()
is preferred. Prior iterations had this implementation,
which resulted in errors due to "complex macros".
c) Trailing semicolon. The macro init_part(name) has
a trailing semicolon as the semicolon is needed for the
inlined macro call that is generated when this macro
expands.
Update: updated to alternative CONFIG_APPLCATION_MEMORY.
Added config option CONFIG_APP_SHARED_MEM to enable a new section
app_smem to contain the shared memory component. This commit
seperates the Kconfig definition from the definition used for the
conditional code. The change is in response to changes in the
way the build system treats definitions. The python script used
to generate a linker script for app_smem was also midified to
simplify the alignment directives. A default linker script
app_smem.ld was added to remove the conditional includes dependency
on CONFIG_APP_SHARED_MEM. By addining the default linker script
the prebuild stages link properly prior to the python script running
Signed-off-by: Joshua Domagalski <jedomag@tycho.nsa.gov>
Signed-off-by: Shawn Mosley <smmosle@tycho.nsa.gov>
The entry point can and therefore should be set by linker
scripts. Whenever possible one should express things in the source
language, be it .c or .ld, and not in code generators or in the build
system.
This patch removes the flag -eCONFIG_KERNEL_ENTRY from the linker's
command line and replaces it with the linker script command
ENTRY(CONFIG_KERNEL_ENTRY)
Signed-off-by: Sebastian Bøe <sebastian.boe@nordicsemi.no>
intList has been populated with the number of isrs, aka interrupts,
but nothing has not been using this information so we drop it and
everything used to construct it.
Signed-off-by: Sebastian Bøe <sebastian.boe@nordicsemi.no>
Newlib uses any RAM between _end and the bounds of physical
RAM for the _sbrk() heap. Set up a user-writable region
so that this works properly on x86.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
When MMU is enabled and the SOC we are running doesn't have
execute in-place(XIP) the final image will be a monolith which
sits in RAM. In such situations we need to maintain the alignment
for application memory. If not maintained the MMU boot tables
will not be configured properly.
Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
This is an introductory port for Zephyr to be run as a Jailhouse
hypervisor[1]'s "inmate cell", on x86 64-bit CPUs (running on 32-bit
mode). This was tested with their "tiny-demo" inmate demo cell
configuration, which takes one of the CPUs of the QEMU-VM root cell
config, along with some RAM and serial controller access (it will even
do nice things like reserving some L3 cache for it via Intel CAT) and
Zephyr samples:
- hello_world
- philosophers
- synchronization
The final binary receives an additional boot sequence preamble that
conforms to Jailhouse's expectations (starts at 0x0 in real mode). It
will put the processor in 32-bit protected mode and then proceed to
Zephyr's __start function.
Testing it is just a matter of:
$ mmake -C samples/<sample_dir> BOARD=x86_jailhouse JAILHOUSE_QEMU_IMG_FILE=<path_to_image.qcow2> run
$ sudo insmod <path to jailhouse.ko>
$ sudo jailhouse enable <path to configs/qemu-x86.cell>
$ sudo jailhouse cell create <path to configs/tiny-demo.cell>
$ sudo mount -t 9p -o trans/virtio host /mnt
$ sudo jailhouse cell load tiny-demo /mnt/zephyr.bin
$ sudo jailhouse cell start tiny-demo
$ sudo jailhouse cell destroy tiny-demo
$ sudo jailhouse disable
$ sudo rmmod jailhouse
For the hello_world demo case, one should then get QEMU's serial port
output similar to:
"""
Created cell "tiny-demo"
Page pool usage after cell creation: mem 275/1480, remap 65607/131072
Cell "tiny-demo" can be loaded
CPU 3 received SIPI, vector 100
Started cell "tiny-demo"
***** BOOTING ZEPHYR OS v1.9.0 - BUILD: Sep 12 2017 20:03:22 *****
Hello World! x86
"""
Note that the Jailhouse's root cell *has to be started in xAPIC
mode* (kernel command line argument 'nox2apic') in order for this to
work. x2APIC support and its reasoning will come on a separate commit.
As a reminder, the make run target introduced for x86_jailhouse board
involves a root cell image with Jailhouse in it, to be launched and then
partitioned (with >= 2 64-bit CPUs in it).
Inmate cell configs with no JAILHOUSE_CELL_PASSIVE_COMMREG flag
set (e.g. apic-demo one) would need extra code in Zephyr to deal with
cell shutdown command responses from the hypervisor.
You may want to fine tune CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC for your
specific CPU—there is no detection from Zephyr with regard to that.
Other config differences from pristine QEMU defaults worth of mention
are:
- there is no HPET when running as Jailhouse guest. We use the LOAPIC
timer, instead
- there is no PIC_DISABLE, because there is no 8259A PIC when running
as a Jailhouse guest
- XIP makes no sense also when running as Jailhouse guest, and both
PHYS_RAM_ADDR/PHYS_LOAD_ADD are set to zero, what tiny-demo cell
config is set to
This opens up new possibilities for Zephyr, so that usages beyond just
MCUs come to the table. I see special demand coming from
functional-safety related use cases on industry, automotive, etc.
[1] https://github.com/siemens/jailhouse
Reference to Jailhouse's booting preamble code:
Origin: Jailhouse
License: BSD 2-Clause
URL: https://github.com/siemens/jailhouse
commit: 607251b44397666a3cbbf859d784dccf20aba016
Purpose: Dual-licensing of inmate lib code
Maintained-by: Zephyr
Signed-off-by: Gustavo Lima Chaves <gustavo.lima.chaves@intel.com>
- _arch_user_mode_enter() implemented
- _arch_is_user_context() implemented
- _new_thread() will honor K_USER option if passed in
- System call triggering macros implemented
- _thread_entry_wrapper moved and now looks for the next function to
call in EDI
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
This was felt to be necessary at one point but actually isn't.
- When a thread is initialized to use a particular stack, calls will be
made to the MMU/MPU to restrict access to that stack to only that
thread. Once a stack is in use, it will not be generally readable even
if the buffer exists in application memory space.
- If a user thread wants to create a thread, we will need to have some
way to ensure that whatever stack buffer passed in is unused and
appropriate. Since unused stacks in application memory will be generally
accessible, we can just check that the calling thread to
k_thread_create() has access to the stack buffer passed in, it won't if
the stack is in use.
On ARM we had a linker definition for .stacks, but currently stacks are
just tagged with __noinit (which is fine).
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
All system calls made from userspace which involve pointers to kernel
objects (including device drivers) will need to have those pointers
validated; userspace should never be able to crash the kernel by passing
it garbage.
The actual validation with _k_object_validate() will be in the system
call receiver code, which doesn't exist yet.
- CONFIG_USERSPACE introduced. We are somewhat far away from having an
end-to-end implementation, but at least need a Kconfig symbol to
guard the incoming code with. Formal documentation doesn't exist yet
either, but will appear later down the road once the implementation is
mostly finalized.
- In the memory region for RAM, the data section has been moved last,
past bss and noinit. This ensures that inserting generated tables
with addresses of kernel objects does not change the addresses of
those objects (which would make the table invalid)
- The DWARF debug information in the generated ELF binary is parsed to
fetch the locations of all kernel objects and pass this to gperf to
create a perfect hash table of their memory addresses.
- The generated gperf code doesn't know that we are exclusively working
with memory addresses and uses memory inefficently. A post-processing
script process_gperf.py adjusts the generated code before it is
compiled to work with pointer values directly and not strings
containing them.
- _k_object_init() calls inserted into the init functions for the set of
kernel object types we are going to support so far
Issue: ZEP-2187
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Kernel data size shifts in between linker passes due to the addition
of the page tables. We would like application memory bounds to
remain fixed so that we can program the MMU permissions for it
at build time.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
We now create a special IA hardware task for handling
double faults. This has a known good stack so that if
the kernel tries to push stack data onto an unmapped page,
we don't triple-fault and reset the system.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
We will need this for stack memory protection scenarios
where a writable GDT with Task State Segment descriptors
will be used. The addresses of the TSS segments cannot be
put in the GDT via preprocessor magic due to architecture
requirments that the address be split up into different
fields in the segment descriptor.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Different areas of memory will need to have different access
policies programmed into the MMU. We introduce MMU page alignment
to the following areas:
- The boundaries of the image "ROM" area
- The beginning of RAM representing kernel datas/bss/nonit
- The beginning of RAM representing app datas/bss/noinit
Some old alignment directives that are no longer necessary have
been removed.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Implements CONFIG_APPLICATION_MEMORY for x86. Working in
XIP and non-XIP configurations.
This patch does *not* implement any alignment constraints
imposed by the x86 MMU, such enabling will be done later.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
This is unmaintained and currently has no known users. It was
added to support a Wind River project. If in the future we need it
again, we should re-introduce it with an exception-based mechanism
for catching out-of-bounds memory queries from the debugger.
The mem_safe subsystem is also removed, it is only used by the
GDB server. If its functionality is needed in the future, it
shoudl be replaced with an exception-based mechanism.
The _image_{ram, rom, text}_{start, end} linker variables have
been left in place, they will be re-purposed and expanded to
support memory protection.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
Macro is used to create a structure to specify the boot time
page table configuration. Needed by the gen_mmu.py script to generate
the actual page tables.
Linker script is needed for the following:
1. To place the MMU page tables at 4KByte boundary.
2. To keep the configuration structure created by
the Macro(mentioned above).
Signed-off-by: Adithya Baglody <adithya.nagaraj.baglody@intel.com>
Inserting the IDT results in any data afterwards being shifted.
We want the memory addresses between the zephyr_prebuilt.elf
and zephyr.elf to be as close as possible. Insert some dummy
data in the linker script the same size as the gen_idt data
structures. Needed for forthcoming patches which generate MMU
page tables at build time.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
For various reasons its often necessary to generate certain
complex data structures at build-time by separate tools outside
of the C compiler. Data is populated to these tools by way of
special binary sections not intended to be included in the final
binary. We currently do this to generate interrupt tables, forthcoming
work will also use this to generate MMU page tables.
The way we have been doing this is to generatea "kernel_prebuilt.elf",
extract the metadata sections with objcopy, run the tool, and then
re-link the kernel with the extra data *and* use objcopy to pull
out the unwanted sections.
This doesn't scale well if multiple post-build steps are needed.
Now this is much simpler; in any Makefile, a special
GENERATED_KERNEL_OBJECT_FILES variable may be appended to containing
the filenames to the generated object files, which will be generated
by Make in the usual fashion.
Instead of using objcopy to pull out, we now create a linker-pass2.cmd
which additionally defines LINKER_PASS2. The source linker script
can #ifdef around this to use the special /DISCARD/ section target
to not include metadata sections in the final binary.
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
In order for OpenOCD to have a high-level view of an RTOS, it uses the
GDB protocol to obtain symbols from the system.
The GDB protocol, however, does not allow obtaining fields from
structures directly, and hardcoding offsets is not only brittle (due to
possibly different architectures or changes in the code), it's also
infeasible considering Zephyr is highly-configurable and parts of key
structs can be compiled in or out.
Export an array with offsets for these key structs. Also add a version
element in that array to allow changes in those structs.
Change-Id: I83bcfa0a7bd57d85582e5ec6efe70e1cceb1fc51
Signed-off-by: Leandro Pereira <leandro.pereira@intel.com>
Replace the existing Apache 2.0 boilerplate header with an SPDX tag
throughout the zephyr code tree. This patch was generated via a
script run over the master branch.
Also updated doc/porting/application.rst that had a dependency on
line numbers in a literal include.
Manually updated subsys/logging/sys_log.c that had a malformed
header in the original file. Also cleanup several cases that already
had a SPDX tag and we either got a duplicate or missed updating.
Jira: ZEP-1457
Change-Id: I6131a1d4ee0e58f5b938300c2d2fc77d2e69572c
Signed-off-by: David B. Kinder <david.b.kinder@intel.com>
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
If a particular project needs to add additional data to the
binary image, in most cases the entire linker script needs to
forked into the project space, causing maintenance issues if
the main linker script is changed.
Now we add some Kconfig options to allow a project to specify
some additional linker scripts which get included by the main
one in a few key areas:
1) In the definition to the 'rodata' section, which can allow
additional data to be included in this ROM section.
2) In the definition to the 'datas' section, which allows
additional data to be included in this RAM section.
3) Arbitrary additional sections to be included at the end of
the binary.
For 1 and 2, this is useful to include data generated outside of
the normal C compilation, such as data structures that are created
by special build tools.
3 is useful for including arbitrary binary blobs inside the final
image, such as for peripheral or co-processor firmware.
Change-Id: I5738d3d6da25f5bc96cda8ae806bf1a3fb34bd5d
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
There are a number of data sections that are repeated across
all the linker scripts for various architecture. In practice these
don't always get updated and we have had problems with bit-rot.
Consolidate these to make maintenance easier.
x86 linker scripts now follow the same naming convention and we
get rid of a linker-epilog.h that wasn't necessary and whose purpose
has been lost to the mists of time. If applications want to define their
own sections they should be allowed to. Linker scripts for x86 do not
end with .h any more, they are not C header files even though we use
C's preprocessor.
Issue: ZEP-688
Change-Id: I893eb4619969695c1f980efd7c2ec9fa5dad136d
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
2016-10-31 18:00:58 -07:00
Renamed from include/arch/x86/linker-common-sections.h (Browse further)
