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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>
2017-01-11 00:24:30 +01:00
/*
* Copyright (c) 2016 Jean-Paul Etienne <fractalclone@gmail.com>
*
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>
2017-01-18 17:01:01 -08:00
* SPDX-License-Identifier: Apache-2.0
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>
2017-01-11 00:24:30 +01:00
*/
arch: migrate includes to <zephyr/...> In order to bring consistency in-tree, migrate all arch code to the new prefix <zephyr/...>. Note that the conversion has been scripted, refer to zephyrproject-rtos#45388 for more details. Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
2022-05-06 10:49:15 +02:00
#include <zephyr/irq.h>
arch: riscv: idle: trace idle and call wfi While going to idle may require SoC specific implementations, provide a more sensible default implementation. Signed-off-by: Gerard Marull-Paretas <gerard@teslabs.com>
2024-01-10 12:54:55 +01:00
#include <zephyr/tracing/tracing.h>
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>
2017-01-11 00:24:30 +01:00
arch: use same syntax for custom arch calls Use same Kconfig syntax for those custom arch call. Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2024-07-05 05:52:13 -04:00
#ifndef CONFIG_ARCH_HAS_CUSTOM_CPU_IDLE
arch: custom cpu_idle and cpu_atomic harmonization custom arch_cpu_idle and arch_cpu_atomic_idle implementation was done differently on different architectures. riscv implemented those as weak symbols, xtensa used a kconfig and all other architectures did not really care, but this was a global kconfig that should apply to all architectures. Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2024-07-04 14:37:08 -04:00
void arch_cpu_idle(void)
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>
2017-01-11 00:24:30 +01:00
{
arch: riscv: idle: trace idle and call wfi While going to idle may require SoC specific implementations, provide a more sensible default implementation. Signed-off-by: Gerard Marull-Paretas <gerard@teslabs.com>
2024-01-10 12:54:55 +01:00
sys_trace_idle();
__asm__ volatile("wfi");
arch: riscv: Add support for CPU load measuring Add sys_trace_idle_exit to RISCV cpu_idle functions and allow enabling CPU_LOAD module for RISCV and disable it for SMP. Signed-off-by: Krzysztof Chruściński <krzysztof.chruscinski@nordicsemi.no>
2025-03-20 09:49:09 +01:00
sys_trace_idle_exit();
arch: riscv: disable interrupts before `wfi` According to RISC-V Instruction Set Manual Chapter 3.3.2: "The operation of WFI must be unaffected by the global interrupt bits in mstatus [...] WFI is also required to resume execution for locally enabled interrupts pending at any privilege level, regardless of the global interrupt enable at each privilege level." Disabling interrupts before executing `wfi` prevents a corner case where an IRQ is presented just before executing `wfi`, which would cause it to return directly into `wfi` and potentially get stuck in sleep, instead of continuing to background processing. When execution is resumed, interrupts are reenabled and appropriate IRQ Handlers should be executed. Signed-off-by: Marcin Szymczyk <marcin.szymczyk@nordicsemi.no>
2024-03-14 16:57:42 +01:00
irq_unlock(MSTATUS_IEN);
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>
2017-01-11 00:24:30 +01:00
}
arch: custom cpu_idle and cpu_atomic harmonization custom arch_cpu_idle and arch_cpu_atomic_idle implementation was done differently on different architectures. riscv implemented those as weak symbols, xtensa used a kconfig and all other architectures did not really care, but this was a global kconfig that should apply to all architectures. Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2024-07-04 14:37:08 -04:00
#endif
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>
2017-01-11 00:24:30 +01:00
arch: use same syntax for custom arch calls Use same Kconfig syntax for those custom arch call. Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2024-07-05 05:52:13 -04:00
#ifndef CONFIG_ARCH_HAS_CUSTOM_CPU_ATOMIC_IDLE
arch: custom cpu_idle and cpu_atomic harmonization custom arch_cpu_idle and arch_cpu_atomic_idle implementation was done differently on different architectures. riscv implemented those as weak symbols, xtensa used a kconfig and all other architectures did not really care, but this was a global kconfig that should apply to all architectures. Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2024-07-04 14:37:08 -04:00
void arch_cpu_atomic_idle(unsigned int key)
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>
2017-01-11 00:24:30 +01:00
{
arch: riscv: idle: trace idle and call wfi While going to idle may require SoC specific implementations, provide a more sensible default implementation. Signed-off-by: Gerard Marull-Paretas <gerard@teslabs.com>
2024-01-10 12:54:55 +01:00
sys_trace_idle();
__asm__ volatile("wfi");
arch: riscv: Add support for CPU load measuring Add sys_trace_idle_exit to RISCV cpu_idle functions and allow enabling CPU_LOAD module for RISCV and disable it for SMP. Signed-off-by: Krzysztof Chruściński <krzysztof.chruscinski@nordicsemi.no>
2025-03-20 09:49:09 +01:00
sys_trace_idle_exit();
arch: riscv: disable interrupts before `wfi` According to RISC-V Instruction Set Manual Chapter 3.3.2: "The operation of WFI must be unaffected by the global interrupt bits in mstatus [...] WFI is also required to resume execution for locally enabled interrupts pending at any privilege level, regardless of the global interrupt enable at each privilege level." Disabling interrupts before executing `wfi` prevents a corner case where an IRQ is presented just before executing `wfi`, which would cause it to return directly into `wfi` and potentially get stuck in sleep, instead of continuing to background processing. When execution is resumed, interrupts are reenabled and appropriate IRQ Handlers should be executed. Signed-off-by: Marcin Szymczyk <marcin.szymczyk@nordicsemi.no>
2024-03-14 16:57:42 +01:00
irq_unlock(key);
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>
2017-01-11 00:24:30 +01:00
}
arch: custom cpu_idle and cpu_atomic harmonization custom arch_cpu_idle and arch_cpu_atomic_idle implementation was done differently on different architectures. riscv implemented those as weak symbols, xtensa used a kconfig and all other architectures did not really care, but this was a global kconfig that should apply to all architectures. Signed-off-by: Anas Nashif <anas.nashif@intel.com>
2024-07-04 14:37:08 -04:00
#endif
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