Commit Graph

3 Commits

Author SHA1 Message Date
Benjamin Walsh ee659ae1a1 build: add _ASMLANGUAGE to all asm files
This avoids asm files from having to explicitly define the _ASMLANGUAGE
symbol themselves.

Change-Id: I71f5a169f75d7443a58a0365a41c55b20dae3029
Signed-off-by: Benjamin Walsh <walsh.benj@gmail.com>
2017-01-24 13:34:51 +00:00
David B. Kinder ac74d8b652 license: Replace Apache boilerplate with SPDX tag
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>
2017-01-19 03:50:58 +00:00
Jean-Paul Etienne cd83e85edc arch: added support for the riscv32 architecture
RISC-V is an open-source instruction set architecture.
Added support for the 32bit version of RISC-V to Zephyr.

1) exceptions/interrupts/faults are handled at the architecture
   level via the __irq_wrapper handler. Context saving/restoring
   of registers can be handled at both architecture and SOC levels.
   If SOC-specific registers need to be saved, SOC level needs to
   provide __soc_save_context and __soc_restore_context functions
   that shall be accounted by the architecture level, when
   corresponding config variable RISCV_SOC_CONTEXT_SAVE is set.

2) As RISC-V architecture does not provide a clear ISA specification
   about interrupt handling, each RISC-V SOC handles it in its own
   way. Hence, at the architecture level, the __irq_wrapper handler
   expects the following functions to be provided by the SOC level:
   __soc_is_irq: to check if the exception is the result of an
                 interrupt or not.
   __soc_handle_irq: handle pending IRQ at SOC level (ex: clear
                     pending IRQ in SOC-specific IRQ register)

3) Thread/task scheduling, as well as IRQ offloading are handled via
   the RISC-V system call ("ecall"), which is also handled via the
   __irq_wrapper handler. The _Swap asm function just calls "ecall"
   to generate an exception.

4) As there is no conventional way of handling CPU power save in
   RISC-V, the default nano_cpu_idle and nano_cpu_atomic_idle
   functions just unlock interrupts and return to the caller, without
   issuing any CPU power saving instruction. Nonetheless, to allow
   SOC-level to implement proper CPU power save, nano_cpu_idle and
   nano_cpu_atomic_idle functions are defined as __weak
   at the architecture level.

Change-Id: I980a161d0009f3f404ad22b226a6229fbb492389
Signed-off-by: Jean-Paul Etienne <fractalclone@gmail.com>
2017-01-13 19:52:23 +00:00