This is a minimalistic SBI implementation for NuttX.
Provides a single service for now:
- Access to machine timer
Provides a start trampoline to start NuttX in S-mode:
- Exceptions / faults are delegated to S-mode.
- External interrupts are delegated to S-mode.
Machine mode timer is used as follows:
- The timer compare match register reload happens in M-mode, via
call gate "riscv_sbi_set_timer"
- The compare match event is dispatched to S-mode ISR, which will
notify the kernel to advance time
- Clearing the STIP interrupt does not work from S-mode,
so the call gate does this from M-mode
The only supported (tested) target for now is MPFS.
CortexR52 can have a optional FPU.
- VFPv3 with FP16
- Option 1: 16 x double-prevision registers - -mfpu=vfpv3-d16-fp16
- Option 1: 32 x double-prevision registers - -mfpu=vfpv3-fp16
Summary:
- I noticed that ./tools/configure.sh fvp-armv8r:nsh_smp shows
warning: (ARCH_CHIP_FVP_R52 && ARCH_CHIP_FVP_R82) selects ARMV8R_HAVE_GICv3 which has unmet direct dependencies (ARCH_ARM && ARCH_ARMV8R)
- I think ARMV8R_HAVE_GICv3 is only used for aarch32.
- This commit fixes this issue.
Impact:
- None
Testing:
- Tested with nsh_smp on FVP
Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>
This adds functionality to map pages dynamically into kernel virtual
memory. This allows implementing I/O remap for example, which is a useful
(future) feature.
Now, the first target is to support mapping user pages for the kernel.
Why? There are some userspace structures that might be needed when the
userspace process is not running. Semaphores are one such example. Signals
and the WDT timeout both need access to the user semaphore to work
properly. Even though for this only obtaining the kernel addressable
page pool virtual address is needed, for completeness a procedure is
provided to map several pages.
During initialization it isn't possible to use up_puts once it's
protected against concurrent access through a mutex lock. Instead,
using up_putc makes it similar to ESP32S2 and ESP32S3 and perfectly
fits for showprogress usage.
Basic work required for uniprocessor CortexR52 (ARMv8R AARCH32) using
GICv3 and CP15 mapped arch timer.
Tested on ARM FVP 11.20.
Port is based on ARMv8R AARCH64 and ARMv7R code. Excuse possible copy-paste leftovers.
Remove unnecessary reading of the status register when loading / unloading
the FIFOs. Reading from the IP block is slow due to BUS synchronization and
this basically makes the SPI busy loop for no reason at all, destroying the
CPU usage.
The overall benefit of these changes is approx. 25%-points, which is a
MASSIVE improvement.
Adds a driver for an FPGA fabric / CoreSPI implementation.
Supports multiple instances, assuming they reside in some base address,
offsettable by a constant value.
Add an interface that validate if EasyDMA transfer is possible.
EasyDMA cannot access flash memory which can cause hard to detect silent bugs.
This feature is enabled if CONFIG_DEBUG_FEATURES=y and CONFIG_DEBUG_ASSERTIONS=y.
External function to query vbus status. Reading from the block requires
the clock, but if no devices are open -> vbus detect does not work.
This creates a chicken / egg problem, if vbus detect is used to start
the usb device.
bmp388 works poorly as the system fires STOPs even in
a beginning of a transaction. Don't let unrelated STOPs
to distort the data flow.
Signed-off-by: Eero Nurkkala <eero.nurkkala@offcode.fi>
This adds 2 more FPGA I2Cs. Also rework the indexing
so that it matches the earlier work without major changes.
Signed-off-by: Eero Nurkkala <eero.nurkkala@offcode.fi>
This fixes the following issue:
- After sending the address, the driver writes an extra zero
Without this patch, the extra write causes an extra ACK that would
terminate the sequence prematurely. This is observed as data read
corruption.
With this fix, the condition is detected precisely. That being the
case, the sequence is continued with a repeated start, after which
the read continues normally.
Signed-off-by: Eero Nurkkala <eero.nurkkala@offcode.fi>
This incorporates an fpga i2c driver into the existing i2c driver.
This fpga i2c works almost 100% as the MSS i2c, but the difference
is that the fpga driver terminates all transactions with a stop
sent -interrupt. That needs to be handled.
Fpga clock source is also different, act accordingly.
SEC2TICK(10) is an overkill to any app, use just one second instead.
modifyreg32s are simplified as well, no need to clear and set
as set is enough.
Signed-off-by: Eero Nurkkala <eero.nurkkala@offcode.fi>
I2C status register reset value (0xf8) was not handled properly causing unnecessary bus resets.
Added critical section to mpfs_i2c_reset() and removed unnecessary interrupt disabling elsewhere.
Confirmation of the IN request must be done immediately after all data has been transferred,
otherwise sending data when more than one request has been added to the queue will
not work properly.
