This provides an example of Asymmetric Multiprocessing (AMP). The
master from Linux sends pings that this NuttX echoes back. The system
uses RPMsg from OpenAMP.
The Inter-Hart Communication module is present in the vendor's software
stack with the tag "2021.11". The software is present on github at the
polarfire-soc project. The following conditions must be met:
1. FPGA programmed with 2021.11 software
2. HSS (Vendor bootloader) with 2021.11 software
3. U-boot and Linux kernel from 2011.11 software
Currently the IHC works as a slave only on the hart number 4.
On the NuttX side, this patch uses rptun that incorporates rpmsg and
virtio. If it used only rpmsg and virtio, the future maintenance would
likely be much heavier. Using rptun also simplifies many things.
Upon success, the master side from Linux may issue an example test:
root@icicle-kit-es-amp:/opt/microchip/amp/rpmsg-pingpong# ./rpmsg-pingpong
However, the rpmsg-pingpong.c (compiled on target with gcc), may need to
be modified as seen below to match the device id:
- char *rpmsg_dev="virtio0.rpmsg-amp-demo-channel.-1.0";
+ char *rpmsg_dev="virtio0.rpmsg-amp-demo-channel.-1.1024";
This work uses a separate linker script. Due to a bug yet unknown to date,
a small NuttX, when loaded by the vendor HSS bootloader, will cause the
Linux kernel to hang at boot. Thus, the binary size is increased with
a section 'filler_area' whose only purpose is to increase the image size
so that the Linux kernel will boot up.
Signed-off-by: Eero Nurkkala <eero.nurkkala@offcode.fi>
Enable this option to optimization the unused input sections with the
linker by compiling with " -ffunction-sections -fdata-sections ", and
linking with " --gc-sections ".
Signed-off-by: chao.an <anchao@xiaomi.com>
## Summary
A lot of linker scripts were listed twice, once for unix, once for windows.
This PR cleans up the logic so they're only listed once.
## Impact
Any opportunity to use a single source of truth and reduce lines of code is a win!
## Testing
CI will test all build
Summary:
- Apply the same style as sabre-6quad
Impact:
- None
- NOTE: esp32c3-devkit still remains old style because of link errors
Testing:
- Build only
Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>
The old implementation used the default ld.script for the kernel side
which did not obey the memory.ld limits whatsoever.
Also, provide the user space addresses from the linker script to get rid
of the pre-processor macros that define (incorrect) default values for
the user space composition.
Polarfire Icicle board has only (128K - 256) bytes for the bootloader
in the non-volatile eNVM. This space is barely enough for running NuttX.
If OpenSBI is selected, it will be placed in DDR. This all means the
nuttx.bin file grows into gigabyte size, filling the unused space (ddr -
envm) with zeroes.
The memory layout is as follows:
MEMORY
{
ddr (rx) : ORIGIN = 0x80000000, LENGTH = 4M
envm (rx) : ORIGIN = 0x20220100, LENGTH = 128K - 256
l2lim (rwx) : ORIGIN = 0x08000000, LENGTH = 1024k
l2zerodevice (rwx) : ORIGIN = 0x0A000000, LENGTH = 512k
}
OpenSBI library is used as a separate binary, which is stored into
eMMC or SD-card. It is then loaded into its precise location in DDR.
Thus, we separate OpenSBI from NuttX and end up with two images
by utilizing the objcopy options:
--only-section=sectionpattern (-j in short)
--remove-section=sectionpattern (-R in short)
This is only valid when CONFIG_MPFS_OPENSBI is set.
Signed-off-by: Eero Nurkkala <eero.nurkkala@offcode.fi>
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>
