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

lib: sbi: Move trap delegation setup to sbi_trap.c

2026-07-21T06:20:46Z

Currently, the trap delegation setup is part of sbi_hart.c and called via sbi_hart_init() whereas the per-hart trap (aka exception and interrupt) handling is part of sbi_trap.c. Move trap delegation init to sbi_trap.c and call it via new sbi_trap_init() from both cold boot and warm boot path. This way trap delegation setup is in same place as trap handling. Signed-off-by: Anup Patel Link: https://lore.kernel.org/r/20260613132129.2135128-2-anup.patel@oss.qualcomm.com Signed-off-by: Anup Patel

lib: sbi: Apply budget restriction when polling Zkr CSR state transition

2026-06-12T13:29:16Z

Zkr architecture doesn't define a time limit on state transitions which results in hanging on unresponsive or event-driven platforms. To prevent this, we need to limit polling iterations and fall back in case the budget is over, and stack guard keeps its initial value. The budget is configurable with CONFIG_ZKR_POLL_BUDGET, defaulting to 1000 iterations. Successful reads do not consume a try. Signed-off-by: Evgeny Voevodin Reviewed-by: Anup Patel Link: https://lore.kernel.org/r/20260519225014.244672-1-evvoevod@tenstorrent.com Signed-off-by: Anup Patel

lib: sbi: add UBSan support

2026-06-12T06:28:35Z

UBSan (Undefined Behavior Sanitizer) is a tool implemented using compiler instrumentation at runtime that allows checking for statements whose output is not deterministic or defined by the C standard. Compiling and running OpenSBI with UBSan instrumentation will print a message in the console if any sentence performs such an action. Support involves two main components: 1. The UBSan implementation hooks (derived from NetBSD), used by the compiler to handle the check output. 2. A test suite integrated with the SBI unit test framework to verify correct operation at runtime. Usage: make UBSAN=y PLATFORM=generic ... The test suite is built when both UBSAN=y and CONFIG_SBIUNIT=y are enabled. When UBSan is enabled, FW_PAYLOAD_OFFSET may need to be increased due to the size increase added by the instrumentation. A value of 0x400000 has been tested. UBSan adds runtime overhead and is intended for development builds only, not for production. Note: This patch marks __stack_chk_guard in sbi_init.c as a weak symbol to prevent multiple definition errors at compile time with UBSan instrumentation enabled. This resolves the conflict between the .globl definitions in sbi_init.c and test_head.S. Signed-off-by: Marcos Oduardo Reviewed-by: Anup Patel Link: https://lore.kernel.org/r/20260515163321.2038366-1-marcos.oduardo@gmail.com Signed-off-by: Anup Patel

lib: sbi: Move Zkr entropy initialization from fw_base.S to init_coldboot

2026-05-09T07:29:43Z

Current placement of entropy initialization via Zkr extension requires a trap-based mechanism to handle absent Zkr extension case. In presence of Smrnmi extension no trap-based mechanisms should be used before Smrnmi is detected and enabled otherwise trap will jump to undefined location. Move stack guard initialization into init_coldboot function body after device tree has been parsed so we know if Zkr extension is implemented by the platform which helps to avoid trap-based discovery. init_coldboot() is a safe place to initialize entropy because it doesn't return so no check of __stack_chk_guard against value on entry will be done. Signed-off-by: Evgeny Voevodin Reviewed-by: Anup Patel Link: https://lore.kernel.org/r/acd52b0f3468758bc5f09e6a45662341b31d4d87.1778176768.git.evvoevod@tenstorrent.com Signed-off-by: Anup Patel

lib: sbi_init: Call hart init and timer init before platform early init

2026-03-22T05:46:33Z

To allow the platform early drivers to use the sbi_timer_mdelay(), sbi_timer_udelay() and sbi_hart_has_extension() helpers, reorder the initialization sequence must call sbi_hart_init() and sbi_timer_init() prior to sbi_platform_early_init() during both cold and warm boot paths. Reviewed-by: Greentime Hu Reviewed-by: Zong Li Signed-off-by: Yu-Chien Peter Lin Link: https://lore.kernel.org/r/20260224031733.3817148-2-peter.lin@sifive.com Signed-off-by: Anup Patel

lib: sbi: Factor-out PMP programming into separate sources

2025-12-16T14:46:47Z

The PMP programming is a significant part of sbi_hart.c so factor-out this into separate sources sbi_hart_pmp.c and sbi_hart_pmp.h for better maintainability. Signed-off-by: Anup Patel Link: https://lore.kernel.org/r/20251209135235.423391-6-apatel@ventanamicro.com Signed-off-by: Anup Patel

lib: sbi: Replace sbi_hart_pmp_xyz() and sbi_hart_map/unmap_addr()

2025-12-16T14:46:47Z

The sbi_hart_pmp_xyz() and sbi_hart_map/unmap_addr() functions can now be replaced by various sbi_hart_protection_xyz() functions. Signed-off-by: Anup Patel Link: https://lore.kernel.org/r/20251209135235.423391-5-apatel@ventanamicro.com Signed-off-by: Anup Patel

lib: sbi: Introduce hart protection abstraction

2025-12-16T14:46:47Z

Currently, PMP and ePMP are the only hart protection mechanisms available in OpenSBI but new protection mechanisms (such as Smmpt) will be added in the near future. To allow multiple hart protection mechanisms, introduce hart protection abstraction and related APIs. Signed-off-by: Anup Patel Link: https://lore.kernel.org/r/20251209135235.423391-3-apatel@ventanamicro.com Signed-off-by: Anup Patel

lib: sbi: Introduce IPI device rating

2025-09-16T04:26:31Z

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 Tested-by: Nick Hu Link: https://lore.kernel.org/r/20250904052410.546818-2-apatel@ventanamicro.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