This extracts the printing of fatal exception information into
its own function to declutter xtensa_excint1_c().
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
There are known exceptions which are not fatal, and we need to
handle them properly by returning to the fixup addresses as
indicated. This adds the code necessary in the exception
handler for this situation.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
When MMU is enabled, we need some scratch registers to preload
page table entries. So update gen_zsr.py to that.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
This changes the TLB misses handling back to the assembly
in user exception, and any page faults during TLB misses to be
handled in double exception handler. This should speed up
simple TLB miss handling as we don't have to go all the way to
the C handler.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
Userspace support for Xtensa architecture using Xtensa MMU.
Some considerations:
- Syscalls are not inline functions like in other architectures because
some compiler issues when using multiple registers to pass parameters
to the syscall. So here we have a function call so we can use
registers as we need.
- TLS is not supported by xcc in xtensa and reading PS register is
a privileged instruction. So, we have to use threadptr to know if a
thread is an user mode thread.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Simplify the logic around xtensa_mmu_init.
- Do not have a different path to init part of kernel
- Call xtensa_mmu_init from C
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
Replace all autorefill helpers with only one that invalidates both,
DTLB and ITLB, since that is what is really needed.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
This register alias was originally introduced to allow A0 to be used
as a scratch register when handling exceptions from MOVSP
instructions. (It replaced some upstream code from Cadence that
hard-coded EXCSAVE1). Now the MMU code is now using too, and for
exactly the same purpose.
Calling it "ALLOCA" is only confusing. Rename it to make it clear
what it's doing.
Signed-off-by: Andy Ross <andyross@google.com>
Some workarounds were introduced for intel cavs2.5 platform bring up.
It is not general so move them to platform code.
Signed-off-by: Rander Wang <rander.wang@intel.com>
This moves the k_* memory management functions from sys/ into
kernel/ includes, as there are kernel public APIs. The z_*
functions are further separated into the kernel internal
header directory.
Also made a quick change to doxygen to group sys_mem_* into
the OS Memory Management group so they will appear in doc.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
z_mp_entry has been removed from Xtensa architecture.
So there is no need for a function declaration. Remove it.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
This provides custom memory range check functions as
it gets a bit complicated with cached/uncached regions.
These functions are marked as __weak so SoC or board
can override these if needed.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
This adds support for using coredump with Xtensa DC233C core,
which are being used by qemu_xtensa and qemu_xtensa_mmu.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
arch_switch() is basically an alias to xtensa_switch() so
we can mark arch_switch() as ALWAYS_INLINE to avoid another
function call, especially when no optimization is used when
debugging.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
This adds a function arch_xtensa_mmu_post_init() which can
be implemented on the SoC layer to perform additional MMU
initialization steps if necessary.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
...VECBASE during MMU initialization. This is to make sure
that we can use the TLB miss handling in the exception
vector after we have moved back the VECBASE during MMU
initialization. Or else we would be forever stuck in ITLB
miss because the exception vectors are not in TLB and we
cannot populate the TLB because those vectors are not in
TLB.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
...and move it to xtensa_mmu_priv.h.
This would allow the SoC layer to use the RING number if needed.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
This adds arch_reserved_pages_update() which is called in
k_mem_manage_init() to reserve some physical pages so they
are not re-mapped. This is due to Zephyr's linker scripts
for Xtensa which often puts something before z_mapped_start
(aka .text, for example, vecbase). That space needs to be
reserved or else k_mem_map() would be mapping those that
could result in faults.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Instead of only handling data TLB misses for VECBASE, change it
to handle all data TLB misses in the double exception handler.
It is because we may encounter data TLB misses when trying to
preload page table entries inside user exception handler.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
If CONFIG_XTENSA_RPO_CACHE is not enabled, it can be assumed
that memory is not double mapped in hardware for cached and
uncached access. So we can specify those regions to have
cache via TLB.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Simply using __data_start and __data_end is not enough as
it leaves out kobject regions which is supposed to be
near .data section. So use _image_ram_start and
_image_ram_end instead to enclose data, bss and various
kobject regions (among others).
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
During MMU initialization, we clear TLB way 6 to remove all
identity mapping. Depending on CPU configuration, there are
certain number of entries per way. So use the number from
core-isa.h to clear enough entries instead of hard-coded
number 8. Specifying an entry number outside of permitted
range may result in CPU reacting in weird way so better to
avoid that.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
This removes the identity map of the first 512MB in TLB way 6.
Or else it would interfere with mapped entries resulting in
double mapped TLB exception.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
MMU needs to be initialized before going in to C, so
z_xtensa_mmu_init() is called in crt1.S before call
to z_cstart(). Note that this is the default case
and crt1.S can be disabled if board and SoC desire
to do so.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Turns out not all MMU enabled Xtensa cores have vaddrstatus,
vaddr0 and vaddr1. And there does not seem to be a way to
determine whether they are available. So remove them from
the exception printout for now.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Refactor the ESP32 target SOCs together with
all related boards. Most braking changes includes:
- changing the CONFIG_SOC_ESP32* to refer to
the actual soc line (esp32,esp32s2,esp32s3,esp32c3)
- replacing CONFIG_SOC with the CONFIG_SOC_SERIES
- creating CONFIG_SOC_FAMILY_ESP32 to embrace all
the ESP32 across all used architectures
- introducing CONFIG_SOC_PART_NUMBER_* to
provide a SOC model config
- introducing the 'common' folder to hide all
commonly used configs and files.
- updating west.yml to reflect previous changes in hal
Signed-off-by: Marek Matej <marek.matej@espressif.com>
xt-clang likes to remove any consecutive NOPs more than 8. So
we need to force the function to have no optimization to avoid
this behavior and to retain all those NOPs.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
This adds a Kconfig to introduce the Xtensa specific
arch_spin_relax() which can do more NOPs. Some Xtensa SoCs
may need more NOPs after failure to lock a spinlock,
especially under SMP. This gives the bus extra time to
propagate the RCW transactions among CPUs.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Allow builds which has CONFIG_MULTITHREADING disabled.
This is reduce code footprint which is handy for
constrained targets as bootloaders.
Signed-off-by: Marek Matej <marek.matej@espressif.com>
This make MCUboot build as Zephyr application.
Providing optinal 2nd stage bootloader to the
IDF bootloader, which is used by default.
This provides more flexibility when building
and loading multiple images and aims to
brings better DX to users by using the sysbuild.
MCUboot and applications has now separate
linker scripts.
Signed-off-by: Marek Matej <marek.matej@espressif.com>
This adds code to always map data TLB for VECBASE so that
we would be dealing with fewer data TLB misses during
exception handling. With VECBASE always mapped, there is
no need to pre-load anymore.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
This moves the TLB miss handling to the C exception handler.
This also allows us to handle page faults (for example,
unmapped pages) during this time as any more exceptions
handled in the C handler will not trigger the double
exception handler but the same C handler.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Instead of being able to arbitrarily set the PTEVADDR for page
table, this provides choices (currently just one). This is in
preparation to enable handling memory management exception in
C code. For that to work, we will need to pre-load the page
table address (PTEVADDR) for the memory page containing
exception code and data (containing jump addresses), and
various stacks. This is to prempt any TLB misses during handling
the level 1 interrupt code. If a TLB miss is encountered during
handling of level 1 interrupt, we will be thrown into double
exception handling code where we will get stuck in infinite
loop. However, in order to pre-load the page table entries,
PTEVADDR needs to be calculated. This requires the use of
PTEVADDR base which cannot be loaded via l32r, as we may cause
a data TLB miss. So we must be able to grab the PTEVADDR base
address strictly within code, and must be without any data
load. So changing CONFIG_XTENSA_MMU_PTEVADDR to be based on
choice so we can have pre-defined bit shift value for shift
operation. This shift value will be used in exception handling
code.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
Add a build option to tell if memory should be mapped in cached
and uncachedr regions.
If the memory is neither in cached nor uncached region it is not double
mapped.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
Initial support for Xtensa MMU version 3. It is using a two level page
table based on fact that the page table is in the virtual space. Only
the top level (page directory) is wired mapped in the TLB to avoid
second level page miss.
The mapped memory is completely fragmented in multiple sections, maybe
we find a better way in future.
The exception handler is where we effectively map the memory, the way it
works is:
1) SW try to access some memory address
2) The address is not mapped, so the MMU will try the auto-refill,
looking the page table
3) The page table contents is not mapped (remember, just the top-level page
is mapped)
4) An exception will be triggered, in the exception we try to read the
portion of the page table that maps the original address
5) The address is not mapped, so the MMU will try again the auto-refill.
This time though, the address is mapped by the top level page that is
properly mapped. (The top-level page maps the page table itself).
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
In z_xtensa_backtrace_print the parameter depth is checked for <= 0.
There is no need to check it again later, also, since the variable is
not used after the while loop we can use directly the parameter without
an additional variable.
Signed-off-by: Flavio Ceolin <flavio.ceolin@intel.com>
The "cross stack call" mechanism has intermediate states where the
stack frames are not valid for our own interrupt entry code, which
causes corruption if an interrupt races at exactly the right time.
Leave interrupts masked until just before the call.
The fix is midly complicated by the fact that we RELY on nested window
exception frames to spill registers from the interruptee, so have to
do the masking with PS.INTLEVEL, which requires a register to save its
contents, which we don't have since everything needs to happen in one
4-register window. But thankfully our Zephyr-reserved EPS register is
guaranteed to be available through this process.
Fixes#57009
Signed-off-by: Andy Ross <andyross@google.com>
Use the common exit() provided by libc so we get standard behavior
across all architectures. So only implement a special exit when
XT_SIMULATOR is defined.
Signed-off-by: Kumar Gala <kumar.gala@intel.com>
The backtrace requires a valid stack pointer to start
printing backtraces. So if there is no stack pointer
being passed in, skip printing backtraces.
Signed-off-by: Daniel Leung <daniel.leung@intel.com>
