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: d844deadec ("lib: sbi: Use hsm stop for hsm wait")
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Nick Hu <nick.hu@sifive.com>
Link: https://lore.kernel.org/r/20250527124821.2113467-1-apatel@ventanamicro.com
Signed-off-by: Anup Patel <anup@brainfault.org>
Zicntr extension specifies three read-only CSRs, time, cycle and
instret. It isn't sufficient to report Zicntr is fully supported with
only time CSR detected.
This patch introduces a bitmap to sbi_hart_features to record
availability of these CSRs, which are detected using traps. Zicntr is
reported as present if and only if three CSRs are all available on the
HARTs.
Sites originally depending on SBI_HART_EXT_ZICNTR for detecting
existence of time CSR are switched to detect SBI_HART_CSR_TIME instead.
Suggested-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Yao Zi <ziyao@disroot.org>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20250516133352.36617-3-ziyao@disroot.org
Signed-off-by: Anup Patel <anup@brainfault.org>
Most CSRs are XLEN bits wide, but some are 64 bit, so rv32 needs two
accesses, plaguing the code with ifdefs.
Add new helpers that split 64 bit operation into two operations on rv32.
The helpers don't use "csr + 0x10", but append "H" at the end of the csr
name to get a compile-time error when accessing a non 64 bit register.
This has the downside that you have to use the name when accessing them.
e.g. csr_read64(0x1234) or csr_read64(CSR_SATP) won't compile and the
error messages you get for these bugs are not straightforward.
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Radim Krčmář <rkrcmar@ventanamicro.com>
Link: https://lore.kernel.org/r/20250429142549.3673976-3-rkrcmar@ventanamicro.com
Signed-off-by: Anup Patel <anup@brainfault.org>
Similarly to what is done for SPELP, handle SSTATUS.SDT upon event
injection. In order to mimick an interrupt, set SDT to 1 for injection and
save its previous value in interrupted_flags[5:5]. Restore it upon
completion.
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
As raised during the ARC review, SPELP was not handled during the event
injection process. Save it as part of the interrupted flags, clear it
before injecting the event and restore it after completion.
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
As raised by Andrew on the kvm-unit-test review, this flags are meant to
hold SSTATUS bits in the specification. Rename them to match that.
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
The latest specification added new high priority RAS events and renamed
the PMU to PMU_OVERFLOW.
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
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 <samuel.holland@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
There is currently no helper for iterating through the harts in a
system, and code must choose between sbi_scratch_last_hartindex() and
sbi_platform_hart_count() for the loop condition.
sbi_scratch_last_hartindex() has unusual semantics, leading to the
likelihood of off-by-one errors, and sbi_platform_hart_count() is
provided by the platform and so may not be properly bounded.
Add a new helper which definitively reports the number of harts managed
by this OpenSBI instance, i.e. the number of valid hart indexes, and a
convenient iterator macro.
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
The compiler generates much better code for sbi_hartindex_to_hartid()
and sbi_hartindex_to_scratch() when using a constant for the bounds
check. This works out nicely because the underlying arrays are already
a constant size, so the only change needed is to fill the remainder of
each array with the appropriate default/out-of-bounds value. The
ellipsis in the designated initializer is a GCC extension (also
supported by Clang), but avoids runtime initialization of the array.
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
The internal limit on the number of harts is SBI_HARTMASK_MAX_BITS, as
this value determines the size of various bitmaps and arrays (including
hartindex_to_hartid_table and hartindex_to_scratch_table). Clamp the
value provided by the platform, and drop the extra array element.
Update the documentation to indicate that hart_index2id must be sized
based on hart_count, and that hart indexes must be contiguous. As of
commit 5e90e54a1a ("lib: utils:Check that hartid is valid"), there is
no restriction on the valid hart ID values.
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
OpenSBI is compiled with -fPIE, which generally implies dynamic linking.
This causes the compiler to generate GOT references for global symbols
in order to support runtime symbol interposition. However, OpenSBI does
not actually perform dynamic linking, so the GOT indirection just adds
unnecessary overhead.
The GOT references can be avoided by declaring global symbols with
hidden visibility, thus making them local to this dynamic object and
non-interposable. GCC/Clang's -fvisibility parameter is insufficient for
this purpose when referencing objects from other translation units;
either __attribute__((visibility(...)) or the pragma is required. Use
the pragma since it is easier to apply to every symbol. Additionally
clean up the one GOT reference from inline assembly.
With this change, a firmware linked with LLD does not contain either a
GOT or a PLT, and a firmware linked with BFD ld contains only a GOT with
a single (unreferenced, legacy) _GLOBAL_OFFSET_TABLE_ entry.
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
This patch adds unit tests for verifying the sbi_ecall version,
impid handling, and extension registration functions. The tests
ensure that the extension registration and unregistration work
as expected.
Signed-off-by: Akshay Behl <akshaybehl231@gmail.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Add SBI_ERR_DENIED_LOCKED and set it as the SBI_LAST_ERR which was
wrongly set to SBI_ERR_BAD_RANGE.
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Currently, the sbi_sse_init() in cold boot path is called after
sbi_domain_finalize() so boot HART of non-root domains will start
before SSE cold boot init which can cause warm boot of such HARTs
to crash in sbi_sse_init().
To address the above issue, factor-out the non-root domain startup
from sbi_domain_finalize() function as a separate sbi_domain_startup()
function which can be called after sbi_sse_init() in cold boot path.
Fixes: 93f7d819fd ("lib: sbi: sse: allow adding new events")
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
The latest SBI 3.0 spec defines a new sbi_mpxy_get_shmem_size()
function and simplifies sbi_mpxy_set_shmem() function so update
the MPXY framework and SBI extension accordingly.
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Align SBI_TRAP_CONTEXT_SIZE to a multiple of 16 bytes. If it is not
aligned to 16 bytes for RV64, it can create performance problems.
Aligning it correctly can fix the performance issues.
Signed-off-by: Raj Vishwanathan <Raj.Vishwanathan@gmail.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
In order to allow events to be dynamically added, remove the existing
static array of events and use a simply linked list of supported events.
This allows us to move the cb_ops into this list and associated it with
an event_id. Drivers can now register cb_ops before bringing up the sse
core to handle additional events (platform ones for instance).
sbi_sse_init() now allocates as many events as present in the linked
list. Events can now be added with sbi_sse_add_event() which allows to
add new supported events with some callback operations if any. If an
event is not to be supported, then sbi_sse_add_event() should not be
called. This approach currently consider that local events are to be
supported on all harts (ie, they all support the same ISA or
dependencies). If per-hart event availability needs to be supported,
then, an is_supported() callback could be added later and called for
each hart.
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Samuel Holland <samuel.holland@sifive.com>
Add a simple singly linked list implementation when double linked list
are not needed. This allows to easily have statically defined linked
list that can be extended at runtime.
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
We will add new functions to sbi_double_trap.c in order to register an
SSE event, split this to a header as part of preparation work.
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
While sbi_pmu_irq_bit() was used to delegate irq to S-mode, LCOFIP usage
was still hardcoded in various places. This led to change the returned
value of sbi_pmu_irq_bit() to be a bit number rather than a bit mask
since it returns an 'int' and we need to obtain the bit number itself to
handle it in the IRQs handlers. Add a similar function to return the
irq mask which can also be used where the mask is required rather than
the bit itself.
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Fix GLOBAL_PLAT_0_START/END definitions. The specification states that
the beginning of the range is 0xc000 and the end is 0xffff.
Reported-by: Andrew Jones <andrew.jones@linux.dev>
Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Add misaligned load/store handling for the vector extension
to the sbi_misaligned_ldst library.
This implementation is inspired from the misaligned_vec_ldst
implementation in the riscv-pk project.
Co-developed-by: Zong Li <zong.li@sifive.com>
Signed-off-by: Zong Li <zong.li@sifive.com>
Signed-off-by: Nylon Chen <nylon.chen@sifive.com>
Reviewed-by: Andy Chiu <andy.chiu@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Implement the SBI MPXY extension which provides an SBI interface to
the supervisor software for send messages via MPXY framework.
Signed-off-by: Rahul Pathak <rpathak@ventanamicro.com>
Co-developed-by: Anup Patel <apatel@ventanamicro.com>
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Allow the supervisor software to query about the event using the
new function. This supports both firmware and hardware events.
The hardware event presence is verified hw_event_map which is populated
via PMU device tree node. The firmware event presence is checked through
event validation function which should take care of both standard and
platform firmware events.
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
The SBI v3.0 introduced a new function to query about the events
without invoking CFG_MATCH. This allows supervisor software to
identify which events are supported on the platform with single
SBI call instead of a CFG_MATCH for each event.
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
As per the updated ISA specification and SBI PMU v3.0, lower 56
bits are available for the platform to implement mhpmeventX
encoding. Implement the PMU raw event V2 support defined in SBI
v3.0 which allows more bits for platforms to encode the raw events.
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
In addition to saving some code size, this moves the decision about
setting the top-level external interrupt handler to the irqchip core,
not the specific driver, which would be needed to support chained
interrupt handlers.
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Now that driver lifecycle is managed from within the SBI irqchip core,
platforms need only to initialize the driver once during cold init.
Remove the remaining platform hooks that are no longer used.
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Currently, each platform keeps track of which irqchip driver is in use
and calls its warm init function. Since the generic platform may use
multiple irqchip drivers, it has logic to track an array of drivers.
The code is simplified and made common across platforms by treating warm
init and exit as properties of the driver, not the platform. Then the
platform's only role is to select and prepare a driver during cold boot.
For now, only add a .warm_init hook, since none of the existing drivers
need an .exit hook. It could be added in the future if needed.
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Have the SBI irqchip core keep track of registered irqchip devices. This
is useful for any callbacks the irqchip driver may have, such as for
warm initialization, the external interrupt handler function, and any
future support for handling external interrupts (beyond IPIs) in M-mode.
This improves on the tracking done in fdt_irqchip.c, as it tracks device
instances, not just drivers, so callbacks can target a specific device.
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
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 <samuel.holland@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
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 78c667b6fc ("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: 78c667b6fc ("lib: sbi: Prefer hartindex over hartid in IPI framework")
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
DBTR introduce a big heap allocation to store hart state, this is
allocated percpu and needs big space when CPU number is high.
Increase the percpu part to fix this problem, and decrease the
fixed part to avoid too big heap size.
Fixes: 97f234f (lib: sbi: Introduce the SBI debug triggers extension support)
Signed-off-by: Inochi Amaoto <inochiama@gmail.com>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
