IRQ_NSTACKS, ARCH_CPU_COUNT, CONFIG_SMP_NCPUS all relate to each
other. However, a bit of clean up can be done and everything can
be merged into SMP_NCPUS.
The MPFS bootloader case works also as it requires only 1 IRQ stack
for the hart that executes as bootloader.
It might be useful to store things in memory per CPU. The tricky part
is that all CPUs run the same code and see the same memory, so some
kind of centralized access is required.
For now, the structure contains the hart id.
Access to the structure elements is provided via sscratch, which is
unique for every hart!
- Add config "ARCH_USE_S_MODE" which controls whether the kernel
runs in M-mode or S-mode
- Add more MSTATUS and most of the SSTATUS register definitions
- Add more MIP flags for interrupt delegation
- Add handling of interrupts from S-mode
- Add handling of FPU from S-mode
- Add new context handling functions that are not dependent on the trap
handlers / ecall
NOTE: S-mode requires a companion SW (SBI) which is not yet implemented,
thus S-mode is not usable as is, yet.
- Add test for mode support, which is architecture dependent
- Add tests for address alignment and region size
- Add option to query for access rights
- The function goes through every PMP entry and tests if an address
range from [base, base+size] has been configured for desired
access rights.
- If several PMP entries match the range and access rights, the
information is combined
- End result is either no access, a partial match was found, or a full
match was found. Details about the partial match are not provided.
The intent for testing access rights and not just blindly applying them
is a case where they are already set in e.g. a bootloader. In this
case, nothing should be done, unless the configuration does not match,
in which case the software must not continue further.
Sv39 is the only mode supported for now. However, it should be trivial
to extend the driver to support the other modes (including Sv32) as well.
The driver is tested with mpfs only, but it should work with any riscv
implementation.
OpenSBI may be compiled as an external library. OpenSBI commit d249d65
(Dec. 11, 2021) needs to be reverted as it causes memcpy / memcmp to
end up in the wrong section. That issue has yet no known workaround.
OpenSBI may be lauched from the hart0 (e51). It will start the U-Boot
and eventually the Linux kernel on harts 1-4.
OpenSBI, once initialized properly, will trap and handle illegal
instructions (for example, CSR time) and unaligned address accesses
among other things.
Due to size size limitations for the mpfs eNVM area where the NuttX
is located, we actually set up the OpenSBI on its own section which
is in the bottom of the DDR memory. Special care must be taken so that
the kernel doesn't override the OpenSBI. For example, the Linux device
tree may reserve some space from the beginning:
opensbi_reserved: opensbi@80000000 {
reg = <0x80000000 0x200000>;
label = "opensbi-reserved";
};
The resulting nuttx.bin file is very large, but objcopy is used to
create the final binary images for the regions (eNVM and DDR) using
the nuttx elf file.
Co-authored-by: Petro Karashchenko <petro.karashchenko@gmail.com>
Signed-off-by: Eero Nurkkala <eero.nurkkala@offcode.fi>
script.
These functions are strongly declared and thus will be used instead of
any other implementation. Furthermore, necessary Kconfig options are
selected to avoid building those function from NuttX's C library.
Signed-off-by: Abdelatif Guettouche <abdelatif.guettouche@espressif.com>
Add a driver for CorePWM block, which can be instantiated on PolarFire SOC FPGA
This supports 2 CorePWM blocks on the FPGA. One CorePWM block provides 8 PWM output signals
Summary:
- ARCH_GLOBAL_IRQDISABLE was initially introduced for LC823450 SMP
- At that time, i.MX6 (quad Cortex-A9) did not use this config
- However, this option is now used for all CPUs which support SMP
- So it's good timing for refactoring the code
Impact:
- Should have no impact because the logic is the same for SMP
Testing:
- Tested with board: spresense:smp, spresense:wifi_smp
- Tested with qemu: esp32-core:smp, maix-bit:smp, sabre-6quad:smp
- Build only: lc823450-xgevk:rndis, sam4cmp-db:nsh
Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>
