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2026-07-21lib: sbi_ipi: Validate hartids against domain, not HSM stateChen Pei
Commit 37eaca4ab33d ("lib: sbi_ipi: Return error for invalid hartids") added a weight check against the HSM-interruptible mask, which excludes harts in STOPPED state. This causes sbi_ipi_send_many() to return SBI_EINVAL when the kernel sends a remote fence (e.g. TLB shootdown) whose hmask includes a hart that was stopped by CPU hotplug: __sbi_rfence_v02_call: hbase = [0] hmask = [0x3] failed (error [-22]) Validate requested hartids against the domain's assigned hartmask instead. This still rejects truly invalid or cross-domain hartids, but allows HSM-STOPPED harts to be silently skipped — which is safe because a stopped hart will do a full local TLB flush on its next HSM start before re-entering S-mode. Fixes: 37eaca4ab33d ("lib: sbi_ipi: Return error for invalid hartids") Signed-off-by: Chen Pei <[email protected]> Reviewed-by: Anup Patel <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Anup Patel <[email protected]>
2025-10-28lib: sbi: Extends sbi_ipi_raw_send() to use all available IPI devicesNick Hu
A platform may contain multiple IPI devices. In certain use cases, such as power management, it may be necessary to send an IPI through a specific device to wake up a CPU. For example, if an IMSIC is powered down and reset, the core cannot receive IPIs from it, so the wake-up must instead be triggered through the CLINT. Suggested-by: Anup Patel <[email protected]> Signed-off-by: Nick Hu <[email protected]> Reviewed-by: Anup Patel <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Anup Patel <[email protected]>
2025-09-16include: sbi: Remove platform specific IPI initAnup Patel
The platform specfic IPI init is not need anymore because using IPI device rating multiple IPI devices can be registered in any order as part of the platform specific early init. Signed-off-by: Anup Patel <[email protected]> Reviewed-by: Samuel Holland <[email protected]> Tested-by: Nick Hu <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Anup Patel <[email protected]>
2025-09-16lib: sbi: Introduce IPI device ratingAnup Patel
A platform can have multiple IPI devices (such as ACLINT MSWI, AIA IMSIC, etc). Currently, OpenSBI rely on platform calling the sbi_ipi_set_device() function in correct order and prefer the first avaiable IPI device which is fragile. Instead of the above, introduce IPI device rating and prefer the highest rated IPI device. This further allows extending the sbi_ipi_raw_clear() to clear all available IPI devices. Signed-off-by: Anup Patel <[email protected]> Tested-by: Nick Hu <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Anup Patel <[email protected]>
2025-04-14lib: sbi_ipi: Return error for invalid hartidsAndrew Jones
sbi_send_ipi() should return SBI_ERR_INVALID_PARAM if even one hartid constructed from hart_mask_base and hart_mask, is not valid. Signed-off-by: Andrew Jones <[email protected]> Reviewed-by: Anup Patel <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Anup Patel <[email protected]>
2024-11-11platform: Drop IPI warm init and exit hooksSamuel Holland
Now that the SBI IPI core clears IPIs at warm boot in a generic way, none of the drivers or platforms use these hooks, and we can remove them. Platforms need only to initialize the driver once during cold init. If other hooks are needed in the future, they can be added to struct sbi_ipi_device. Signed-off-by: Samuel Holland <[email protected]> Reviewed-by: Anup Patel <[email protected]>
2024-11-11lib: sbi_ipi: Move initial IPI clear to sbi_ipi_init()Samuel Holland
sbi_ipi_init() expects the platform warm init function to clear IPIs on the local hart, but there is already a generic function to do this. After this change, none of the existing drivers need a warm init callback. Signed-off-by: Samuel Holland <[email protected]> Reviewed-by: Anup Patel <[email protected]>
2024-11-11lib: sbi_ipi: Make .ipi_clear always target the current hartSamuel Holland
All existing users of this operation target the current hart, and it seems unlikely that a future user will need to clear the pending IPI status of a remote hart. Simplify the logic by changing .ipi_clear (and its wrapper sbi_ipi_raw_clear()) to always operate on the current hart. This incidentally fixes a bug introduced in commit 78c667b6fc07 ("lib: sbi: Prefer hartindex over hartid in IPI framework"), which changed the .ipi_clear parameter from a hartid to a hart index, but failed to update the warm_init functions to match. Fixes: 78c667b6fc07 ("lib: sbi: Prefer hartindex over hartid in IPI framework") Signed-off-by: Samuel Holland <[email protected]> Reviewed-by: Anup Patel <[email protected]>
2024-09-26lib: sbi: Use sbi_hartmask in sbi_hsm_hart_interruptible_mask()Samuel Holland
This removes several hartid/hartindex conversions, as well as two loops through the mask for broadcast IPIs. Signed-off-by: Samuel Holland <[email protected]> Reviewed-by: Anup Patel <[email protected]>
2024-09-26lib: sbi: Simplify halt broadcast logicSamuel Holland
Use the IPI .update callback to exclude the local hart. This allows reusing the normal logic for broadcasting an IPI to all active harts. Signed-off-by: Samuel Holland <[email protected]> Reviewed-by: Anup Patel <[email protected]>
2024-09-25lib: sbi: Use current_hartindex() where possibleSamuel Holland
This avoids calls to the expensive sbi_hartid_to_hartindex() function and also makes the firmware smaller. Signed-off-by: Samuel Holland <[email protected]> Reviewed-by: Anup Patel <[email protected]>
2023-12-18lib: sbi_ipi: Drop unnecessary ipi_process checkSamuel Holland
sbi_ipi_event_create() disallows registering an IPI event with a NULL .process callback, so the function pointer will never be NULL here. Signed-off-by: Samuel Holland <[email protected]> Reviewed-by: Anup Patel <[email protected]> Reviewed-by: Xiang W <[email protected]>
2023-12-18lib: sbi_ipi: Process self-IPIs in sbi_ipi_send()Samuel Holland
An IPI sent to the local hart can be processed directly instead of triggering the IPI device. This is more efficient, and it avoids a deadlock when the .sync callback is defined. Since interrupts are disabled while handling an ecall, the IPI would not get delivered until the next mret, but sbi_ipi_sync() is called before then. Signed-off-by: Samuel Holland <[email protected]> Reviewed-by: Anup Patel <[email protected]> Reviewed-by: Xiang W <[email protected]>
2023-12-18lib: sbi_ipi: Do not ignore errors from sbi_ipi_send()Samuel Holland
Currently, failures in sbi_ipi_send() are silently ignored, which makes them difficult to debug. Instead, abort sending the IPI and pass back the error, but still synchronize any IPIs already sent. Signed-off-by: Samuel Holland <[email protected]> Signed-off-by: Anup Patel <[email protected]>
2023-12-08lib: sbi: Prevent redundant sbi_ipi_processXiang W
Multiple harts may try to send IPI to a particular target hart A in which case the send_ipi() should be called only when the old value of the hart A ipi_type is zero. Signed-off-by: Xiang W <[email protected]> Reviewed-by: Anup Patel <[email protected]>
2023-11-26lib: sbi: Allow relaxed MMIO writes in device ipi_clear() callbackAnup Patel
Currently, there are no barriers before or after the ipi_clear() device callback which forces ipi_clear() device callback to always use non-relaxed MMIO writes. Instead of above, we use wmb() in after the ipi_clear() device callback which pairs with the wmb() done before the ipi_send() device callback. This also allows device ipi_clear() callback to use relaxed MMIO writes. Signed-off-by: Anup Patel <[email protected]> Reported-by: Bo Gan <[email protected]>
2023-11-26lib: sbi: Allow relaxed MMIO writes in device ipi_send() callbackAnup Patel
Currently, we have a smp_wmb() between atomic_raw_set_bit() and ipi_send() device callback whereas the MMIO writes done by the device ipi_send() callback will also include a barrier. We can avoid unnecessary/redundant barriers described above by allowing relaxed MMIO writes in device ipi_send() callback. To achieve this, we simply use wmb() instead of smp_wmb() before calling device ipi_send(). Signed-off-by: Anup Patel <[email protected]> Reported-by: Bo Gan <[email protected]>
2023-09-24lib: sbi: Prefer hartindex over hartid in IPI frameworkAnup Patel
Let us prefer hartindex over hartid in IPI framework which in-turn forces IPI users to also prefer hartindex. Signed-off-by: Anup Patel <[email protected]>
2023-09-24lib: sbi: Extend sbi_hartmask to support both hartid and hartindexXiang W
Currently, the sbi_hartmask is indexed by hartid which puts a limit on hartid to be less than SBI_HARTMASK_MAX_BITS. We extend the sbi_hartmask implementation to use hartindex and support updating sbi_hartmask using hartid. This removes the limit on hartid and existing code works largely unmodified. Signed-off-by: Xiang W <[email protected]> Signed-off-by: Anup Patel <[email protected]>
2023-09-06lib: sbi: improve the definition of SBI_IPI_EVENT_MAXXiang W
The previous definition had the assumption that the machine word length is equal to the word length of LONG. Remove this assumption and add a static check to prevent errors in subsequent modifications. Signed-off-by: Xiang W <[email protected]> Reviewed-by: Anup Patel <[email protected]>
2023-05-11lib: sbi: Simplify sbi_ipi_process remove gotoXiang W
Simplify sbi_ipi_process() by removing goto statement. Signed-off-by: Xiang W <[email protected]> Reviewed-by: Anup Patel <[email protected]>
2023-05-11lib: sbi: Remove unnecessary semicolonXiang W
We have redundant semicolon at quite a few places so let's remove it. Signed-off-by: Xiang W <[email protected]> Reviewed-by: Anup Patel <[email protected]>
2023-04-14lib: sbi: Optimize sbi_tlb queue waitingXiang W
When tlb_fifo is full, it will wait and affect the ipi update to other harts. This patch is optimized. Signed-off-by: Xiang W <[email protected]> Reviewed-by: Anup Patel <[email protected]> Tested-by: Anup Patel <[email protected]>
2023-04-13lib: sbi: Optimize sbi_ipiXiang W
The original sbi_ipi will be processed by hart by hart, after optimization, send ipi first and finally wait together. Signed-off-by: Xiang W <[email protected]> Reviewed-by: Anup Patel <[email protected]> Tested-by: Anup Patel <[email protected]>
2023-03-10lib: sbi: Clear IPIs before init_warm_startup in non-boot hartsEvgenii Shatokhin
Since commit 50d4fde1c5a4 ("lib: Remove redundant sbi_platform_ipi_clear() calls"), the IPI sent from the boot hart in wake_coldboot_harts() is not cleared in the secondary harts until they reach sbi_ipi_init(). However, sbi_hsm_init() and sbi_hsm_hart_wait() are called earlier, so a secondary hart might enter sbi_hsm_hart_wait() with an already pending IPI. sbi_hsm_hart_wait() makes sure the hart leaves the loop only when it is actually ready, so a pending unrelated IPI should not cause safety issues. However, it might be inefficient on certain hardware, because it prevents "wfi" from stalling the hart even if the hardware supports this, making the hart needlessly spin in a "busy-wait" loop. This behaviour can be observed, for example, in a QEMU VM (QEMU 7.2.0) with "-machine virt" running a Linux guest. Inserting delays in sbi_hsm_hart_start() allows reproducing the issue more reliably. The comment in wait_for_coldboot() suggests that the initial IPI is needed in the warm resume path, so let us clear it before init_warm_startup() only. To do this, sbi_ipi_raw_clear() was created similar to sbi_ipi_raw_send(). Signed-off-by: Evgenii Shatokhin <[email protected]> Reviewed-by: Anup Patel <[email protected]>
2023-01-06treewide: Replace TRUE/FALSE with true/falseBin Meng
C language standard uses true/false for the boolean type. Let's switch to that for better language compatibility. Signed-off-by: Bin Meng <[email protected]> Reviewed-by: Anup Patel <[email protected]> Reviewed-by: Samuel Holland <[email protected]> Tested-by: Samuel Holland <[email protected]>
2022-07-11lib: sbi: add check for ipi device for hsm startBen Dooks
If the ecall SBI_EXT_HSM_HART_START is called it might try to wake the secondary hart using sbi_ipi_raw_send() to send an IPI to the hart. This can fail if there is no IPI device but no error is returned from sbi_ipi_raw_send() so the ecall returns as if the action completed and the caller continues without noticing (in the case of Linux it just hangs waiting for the secondary hart to become active) Fix this by changing sbi_ipi_raw_send() to return and error, and if an error is returned, then return it via SBI_EXT_HSM_HART_START call. Signed-off-by: Ben Dooks <[email protected]> Reviewed-by: Anup Patel <[email protected]>
2021-07-11lib: sbi: Implement firmware countersAtish Patra
RISC-V SBI v0.3 specification defines a set of firmware events that can provide additional information about the current firmware context. All of the firmware event monitoring are enabled now. The firmware events must be defined as raw perf event with MSB set as specified in the specification. Reviewed-by: Anup Patel <[email protected]> Signed-off-by: Atish Patra <[email protected]>
2021-06-02lib: sbi_scratch: remove owner from sbi_scratch_alloc_offsetHeinrich Schuchardt
The parameter owner of function sbi_scratch_alloc_offset() is never used. The scratch memory is small. We should not use it for debug information in future. Hence eliminate the parameter. Signed-off-by: Heinrich Schuchardt <[email protected]> Reviewed-by: Xiang W <[email protected]> Reviewed-by: Anup Patel <[email protected]>
2021-04-28lib: sbi: Simplify ipi platform operationsAnup Patel
Instead of having ipi_send() and ipi_clear() callbacks in platform operations, it will be much simpler for ipi driver to directly register these operations as a device to sbi_ipi implementation. Signed-off-by: Anup Patel <[email protected]> Reviewed-by: Alistair Francis <[email protected]>
2021-03-03lib: Remove redundant sbi_platform_ipi_clear() callsAnup Patel
The sbi_platform_ipi_clear() called from wait_for_coldboot() and sbi_hsm_hart_wait() is redundant because IPI will be automatically cleared by sbi_platform_ipi_init() called from sbi_ipi_init(). Further, wait_for_coldboot() is common for warm startup and warm resume path so the sbi_platform_ipi_clear() called in warm resume path cause resuming HART to miss an IPI injected other HART to wakeup the HART. Signed-off-by: Anup Patel <[email protected]> Reviewed-by: Atish Patra <[email protected]>
2021-03-03lib: sbi: Rename sbi_hsm_hart_started_mask() functionAnup Patel
A hart can take interrupt in the new HSM states introduced by the SBI HSM suspend function (such as SUSPENDED state) so we rename sbi_hsm_hart_started_mask() to something more generic such as sbi_hsm_hart_interruptible_mask(). Signed-off-by: Anup Patel <[email protected]> Reviewed-by: Atish Patra <[email protected]>
2020-10-20lib: sbi: Extend sbi_hsm_hart_started_mask() for domainsAnup Patel
The sbi_hsm_hart_started_mask() API should take one more parameter to allow caller specify domain under which started_mask is being generated. Further, the sbi_hsm_hart_started_mask() depends on sbi_hsm_hart_get_state() which also should return HART state under specified domain. This patch updates both sbi_hsm_hart_started_mask() and sbi_hsm_hart_get_state() as-per above. Signed-off-by: Anup Patel <[email protected]> Reviewed-by: Alistair Francis <[email protected]>
2020-03-28include: sbi_ipi: Remove scratch parameter from most functionsAnup Patel
This patch removes scratch parameter from most sbi_ipi functions. Signed-off-by: Anup Patel <[email protected]> Reviewed-by: Atish Patra <[email protected]>
2020-03-19lib: sbi_hsm: Remove scratch parameter from hart_started_mask() APIAnup Patel
The scratch parameter in sbi_hsm_hart_started_mask() API is now redundant hence removing it. Signed-off-by: Anup Patel <[email protected]> Reviewed-by: Bin Meng <[email protected]> Reviewed-by: Atish Patra <[email protected]>
2020-03-19lib: Handle failure of sbi_hartid_to_scratch() APIAnup Patel
The sbi_hartid_to_scratch() API can fail for non-existent HARTs so all uses of sbi_hartid_to_scratch() API should check return value. Signed-off-by: Anup Patel <[email protected]> Reviewed-by: Bin Meng <[email protected]> Reviewed-by: Atish Patra <[email protected]>
2020-03-19include: Simplify HART id to scratch macroAnup Patel
This patch simplify HART id to scratch macro as follows: 1. Remove current "scratch" pointer argument because now we use HART id to scratch table 2. Rename sbi_hart_id_to_scratch() to sbi_hartid_to_scratch() to have macro name consistent with the name of callback in struct sbi_scratch Signed-off-by: Anup Patel <[email protected]> Reviewed-by: Bin Meng <[email protected]> Reviewed-by: Atish Patra <[email protected]>
2020-03-13include: Make sbi_current_hartid() as macro in riscv_asm.hAnup Patel
The sbi_current_hartid() being a regular function is quite expensive because for callers it is a function call instead of a direct CSR read. This patch converts sbi_current_hartid() into a macro in riscv_asm.h. Signed-off-by: Anup Patel <[email protected]> Reviewed-by: Atish Patra <[email protected]>
2020-03-11lib: sbi_ipi: Use sbi_hsm_hart_started_mask() APIAnup Patel
This patch replaces use of sbi_hart_available_mask() API with sbi_hsm_hart_started_mask() API. Signed-off-by: Anup Patel <[email protected]> Reviewed-by: Bin Meng <[email protected]>
2020-02-24lib: Implement hart hotplugAtish Patra
This patch adds support for hart hotplug in OpenSBI using a generic WFI based approach. Hart hotplug can be achieved via SBI HSM extension which allows supervisor mode software to start or stop any harts anytime. Any platform wishes to implement platform specific hart hotplug must implement both hart_start and hart_stop in addition to enable platform feature SBI_PLATFORM_HAS_HART_HOTPLUG. Signed-off-by: Atish Patra <[email protected]> Reviewed-by: Anup Patel <[email protected]>
2020-02-24lib: Simplify the for-loop in sbi_ipi_send_many()Anup Patel
We don't need to separately call sbi_ipi_send() for current HART in sbi_ipi_send_many(). Instead, we can simplify the for-loop in sbi_ipi_send_many() and call sbi_ipi_send() for all HARTs in the for-loop itself. Signed-off-by: Anup Patel <[email protected]> Reviewed-by: Bin Meng <[email protected]>
2020-02-22lib: Use available hart mask for correct hbase valueAtish Patra
As per the latest SBI specification, all online harts should receive IPI if hbase is set to -1. Set the target mask to all available hart mask if hbase is -1. Signed-off-by: Atish Patra <[email protected]> Reviewed-by: Anup Patel <[email protected]>
2020-01-22lib: Initialize TLB management directly from coldboot/warmboot pathAnup Patel
Currently, the remote TLB management is initialized via IPI init which is counter intuitive. This patch initializes remote TLB management directly from init_coldboot() and init_warmboot() after IPI init is done. Signed-off-by: Anup Patel <[email protected]> Reviewed-by: Atish Patra <[email protected]>
2020-01-22lib: Drop _fifo from the name of various sbi_tlb_fifo_xyz() functionsAnup Patel
This patch drops _fifo from the name of various sbi_tlb_fifo_xyz() functions because all these functions deal with remote TLB managment and FIFO is the per-HART data structure used internally by remote TLB implementation. Signed-off-by: Anup Patel <[email protected]> Reviewed-by: Atish Patra <[email protected]>
2020-01-22lib: Introduce sbi_ipi_event_create/destroy() APIsAnup Patel
This patch introduces sbi_ipi_event_create/destroy() APIs and struct sbi_ipi_event_ops for creating/destroying IPI events at runtime based of event operations. This new APIs will help platform code and utils code to create custom IPI events which are not part of generic OpenSBI library. Signed-off-by: Anup Patel <[email protected]> Reviewed-by: Atish Patra <[email protected]>
2020-01-22lib: Introduce sbi_ipi_send_halt() APIAnup Patel
Instead of directly calling sbi_ipi_send_many(), we introduce sbi_ipi_send_halt() for halting a set of HARTs. This way in future we can assign any IPI event number for HART halting within sbi_ipi.c only. Signed-off-by: Anup Patel <[email protected]> Reviewed-by: Atish Patra <[email protected]>
2020-01-22lib: Introduce sbi_ipi_send_smode() APIAnup Patel
Instead of directly calling sbi_ipi_send_many(), we introduce sbi_ipi_send_smode() for injecting S-mode software interrupts. This way in future we can assign any IPI event number for S-mode IPIs within sbi_ipi.c only. Signed-off-by: Anup Patel <[email protected]> Reviewed-by: Atish Patra <[email protected]>
2020-01-22lib: Move struct sbi_ipi_data definition to sbi_ipi.cAnup Patel
The struct sbi_ipi_data is only used in sbi_ipi.c so move it to sbi_ipi.c from sbi_ipi.h. Signed-off-by: Anup Patel <[email protected]> Reviewed-by: Atish Patra <[email protected]>
2020-01-07lib: do sbi_exit() upon halt IPIAnup Patel
Instead of doing sbi_hang() we should do sbi_exit() upon halt IPI. Signed-off-by: Anup Patel <[email protected]> Reviewed-by: Atish Patra <[email protected]>
2020-01-07lib: Add ipi exit APIAnup Patel
We add sbi_ipi_exit() API for exit path handling in sbi_exit() implementation. Signed-off-by: Anup Patel <[email protected]> Reviewed-by: Atish Patra <[email protected]>