opensbi.git/lib/sbi/sbi_hsm.c, branch master

lib: sbi: Add system_resume callback for restoring the system

2025-10-28T05:58:09Z

The last core who performs the system suspend is responsible for restoring the system after waking up. Add the system_resume callback for restoring the system from suspend. Suggested-by: Anup Patel Signed-off-by: Nick Hu Reviewed-by: Anup Patel Link: https://lore.kernel.org/r/20251020-cache-upstream-v7-11-69a132447d8a@sifive.com Signed-off-by: Anup Patel

lib: sbi: Extends sbi_ipi_raw_send() to use all available IPI devices

2025-10-28T05:58:01Z

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 Signed-off-by: Nick Hu Reviewed-by: Anup Patel Link: https://lore.kernel.org/r/20251020-cache-upstream-v7-8-69a132447d8a@sifive.com Signed-off-by: Anup Patel

lib: sbi_hsm: Use 64-bit CSR macro for menvcfg

2025-09-16T04:33:53Z

Simplify the code and remove preprocessor checks by treating menvcfg and menvcfgh together as one 64-bit value. Signed-off-by: Samuel Holland Reviewed-by: Anup Patel Link: https://lore.kernel.org/r/20250908055646.2391370-3-samuel.holland@sifive.com Signed-off-by: Anup Patel

lib: sbi_hsm: Save mideleg across non-retentive suspend

2025-09-16T04:33:53Z

OpenSBI updates mideleg when registering or unregistering the PMU SSE event. The updated CSR value must be saved across non-retentive suspend, or PMU SSE events will not be delivered after the hart is resumed. Fixes: b31a0a24279d ("lib: sbi: pmu: Add SSE register/unregister() callbacks") Signed-off-by: Samuel Holland Reviewed-by: Anup Patel Link: https://lore.kernel.org/r/20250908055646.2391370-1-samuel.holland@sifive.com Signed-off-by: Anup Patel

lib: sbi: Revert entry_count before doing hsm stop in hsm wait loop

2025-06-16T04:10:28Z

Using hsm stop in hsm wait loop causes secondary harts to be stuck forever in OpenSBI on RISC-V platforms where HSM hart hotplug is available and all harts come-up at the same time during system power-on. For example, lets say we have two harts A and B on a RISC-V platform with HSM hart hotplug which come-up at the same time during system power-on. The hart A enters OpenSBI before hart B hence it becomes the primary (or cold-boot) hart whereas hart B becomes the secondary (or warm-boot) hart. The hart A follows the OpenSBI cold-boot path and registers hsm device before hart B enters OpenSBI. The hart B eventually enters OpenSBI and follows the OpenSBI warm-boot path so it will increment it's own entry_count before entering hsm wait loop where it sees hsm device and stops itself. Later as part of the Linux boot-up sequence, hart A issues SBI HSM start call to bring-up hart B but OpenSBI sees entry_count != init_count for hart B in sbi_hsm_hart_start() hence hsm_device_hart_start() is not called for hart B resulting in hart B stuck forever in OpenSBI. To fix the above issue, revert entry_count before doing hsm stop in hsm wait loop. Fixes: d844deadec94 ("lib: sbi: Use hsm stop for hsm wait") Signed-off-by: Anup Patel Reviewed-by: Nick Hu Link: https://lore.kernel.org/r/20250527124821.2113467-1-apatel@ventanamicro.com Signed-off-by: Anup Patel

lib: sbi: Use hsm stop for hsm wait

2025-05-15T12:01:11Z

If we hotplug a core and then perform a suspend-to-RAM operation on a multi-core platform, the hotplugged CPU may be woken up along with the rest of the system, particularly on platforms that wake all cores from the deepest sleep state. When this happens, the hotplugged CPU enters the sbi_hsm_wait WFI wait loop instead of transitioning into a platform-specific low-power state. To address this, we add a HSM stop call within the wait loop. This allows platforms that support HSM stop to enter a low-power state when the CPU is unexpectedly woken up. Signed-off-by: Nick Hu Reviewed-by: Samuel Holland Reviewed-by: Anup Patel Link: https://lore.kernel.org/r/20250418064506.15771-1-nick.hu@sifive.com Signed-off-by: Anup Patel

lib: sbi: Use sbi_hart_count() and sbi_for_each_hartindex()

2025-03-24T12:27:20Z

Simplify the code and improve consistency by using the new macros where possible. sbi_hart_count() obsoletes sbi_scratch_last_hartindex(). Signed-off-by: Samuel Holland Reviewed-by: Anup Patel

lib: sbi: Add optional resume address to hart suspend

2024-12-06T03:56:35Z

Add an optional resume address to the platform specific hart suspend call. Signed-off-by: Subrahmanya Lingappa Signed-off-by: Anup Patel

lib: sbi_ipi: Move initial IPI clear to sbi_ipi_init()

2024-11-11T12:48:35Z

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 Reviewed-by: Anup Patel

lib: sbi: Remove unused hartid parameters

2024-09-26T10:59:29Z

None of these functions use their hartid parameter. Signed-off-by: Samuel Holland Reviewed-by: Anup Patel