RISC-V privilege specification allows the implementation to have less
than 64 bits.
Add a function to detect the number of implemented bits in mhpmcounter
dynamically at runtime.
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
RISC-V ISA specification v1.11 defined mcountinhibit CSR that allows
software to stop any counter from incrementing. The SBI PMU extension
depends on this CSR support in hardware.
Define mcountinhibit as a hart specific feature and detect it at runtime.
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
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 <xypron.glpk@gmx.de>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
csr_read_allowed/csr_read_allowed requires trap.case to detect the results,
but if no exception occurs, the value of trap.case will remain unchanged,
which makes the detection results unreliable. Add code to initialize
trap.case to 0.
Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
We add sbi_hart_reinit() function which will re-initialize HART CSRs
assuming HART features are already detected. This new function will
be useful in re-initializing HART after it resumes from HSM SUSPENDED
state.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We should check and access N-extension CSRs in sbi_hart_switch_mode()
when next_mode is u-mode because N-extension is optional.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
As per RISC-V privilege specification, a platform may choose to implement
a coarser granularity scheme for PMP addresses. In that case, we shouldn't
allow any pmp region size smaller than the platform supports. A platform
may not also implement all the bits for a PMP address specified in the priv
specification.
The pmp range granularity and address bits should be detected dynamically
before detecing PMP regions. Any pmp modification request beyond these detected
value must not succeed.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
We extend boot prints to display details of each domain. In the
process, we remove sbi_hart_pmp_dump() because it shows redundant
information which domain details already show.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
The PMP configuration on each HART should be only based on the memory
regions of the assigned domain because each domain includes a memory
region to protect the underlying firmware.
This patch updates the sbi_hart_pmp_configure() function accordingly.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
The sbi_hart_pmp_get() and sbi_hart_pmp_check_addr() functions
are not used anymore hence this patch removes these functions.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
The hartid parameter of sbi_hart_init() is not used anywhere in
sbi_hart_init() implementation so let's remove it.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
We factor-out PMP configuration from sbi_hart_init() as a separate
sbi_hart_pmp_configure() function and do the PMP configuration very
late in coldboot and warmboot path just before platform_final_init().
Eventually, this enable us to configure PMP totally based on OpenSBI
domain where OpenSBI domains can be parsed from device-tree in any of
the platform operations except platform_final_init().
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
The pmp_region_xyz() callbacks are not required in sbi_platform_operations
because we will be using OpenSBI domain memory regions to program the
PMP CSRs.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
The sbi_ecall.h and sbi_trap.h are not required to be included in
sbi_platform.h hence we remove it. This way sources requiring
these headers will have to explicitly include it thereby reducing
implicit includes.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
HiFive unleashed currently implements fewer than 56 bits of physical
address so existing PMP CSR detection is broken.
PMP address register encodes bits 55-2 of a 56-bit physical address,
Not all physical address bits may be implemented, So just check
minimum 1 bit.
Fixes: 74d1db7062 ("lib: sbi: Improve PMP CSR detection and
progamming")
Signed-off-by: Pragnesh Patel <pragnesh.patel@sifive.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
We extend sbi_hart_pmp_check_addr() API so that users can specify
privilege mode of the address for checking PMP access permissions.
To achieve this, we end-up converting "unsigned long *size" parameter
to "unsigned long *log2len" for pmp_get() implementation so that we
can deal with regions of "1UL << __riscv_xlen" size in a special case
in sbi_hart_pmp_check_addr() implementation.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We rename CAUSE_HYPERVISOR_ECALL to CAUSE_SUPERVISOR_ECALL and
CAUSE_SUPERVISOR_ECALL to CAUSE_VIRTUAL_SUPERVISOR_ECALL so that
it matches latest RISC-V privilege spec.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
A RISC-V platform can leave unimplemented MHPM counters hard-wired
to zero. We extend hart_detect_features() to detect MHPM counters
which are accessible and not hard-wired to zero. We also print
number of available MHPM counters as part of boot prints.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
As-per latest RISC-V privilege spec up to 64 PMP entries are supported.
Implementations may implement zero, 16, or 64 PMP CSRs. All PMP CSR
fields are WARL and may be hardwired to zero.
This patch improves PMP CSR detection and progamming considering
above facts.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
The SBI_HART_HAS_PMP feature is redundant because we already
have number of PMP regions returned by sbi_hart_pmp_count().
Checking whether PMP is supported for a HART can be simply done
by checking non-zero value returned by sbi_hart_pmp_count().
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We should only return valid error codes from SBI ecalls as
defined by the RISC-V SBI spec.
To achieve this:
1. We use SBI_Exxxx defines for OpenSBI internal errors with
error values starting from -1000
2. We use SBI_ERR_xxxx defines for errors defined by SBI spec
3. We map some of the SBI_Exxxx defines to SBI_ERR_xxxx defines
which are semantically same
4. We throw a error print and force return error code to
SBI_ERR_FAILED in sbi_ecall_handler() if we see an invalid
error code being returned to S-mode
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
If the platform doesn't support S-Mode don't print the delegation
registers.
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
To support RISC-V hypervisor v0.6.1, we:
1. Don't need to explicitly forward WFI traps from VS/VU-mode
2. Have to delegate virtual instruction trap to HS-mode
3. Have to update trap redirection for changes in HSTATUS CSR
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
It is not mandatory for a RISC-V systems to implement all PMP
regions so we have to check all PMPADDRx CSRs to determine excat
number of supported PMP regions.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
This patch does few cosmetic improvements to HART feature detection:
1. Remove sbi_ perfix from HART feature detection functions
because all local/static functions in sbi_hart.c don't have
sbi_ prefix
2. Remove sbi_hart_set_feature() because it's quite small and
local/static in sbi_hart.c
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
It makes more sense to have scratch pointer as parameter in
HART feature APIs because:
1. We already have scratch pointer at places where these APIs
are used.
2. This is consistent with lot of other APIs in sbi_hart.h
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We do following improvements for get_feature_str():
1. We should return "none" from get_feature_str() no features
available instead of sbi_boot_prints() explicitly handling
failure.
2. We don't need to return failure (just like misa_xlen())
because we are returning "none" for no features and we are
truncating output when space is not available.
3. Based on 1 and 2, the sbi_boot_prints() can be further
simplified.
4. No need for two char[] in sbi_boot_prints()
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We should detect HART features in sbi_hart_init() before
mstatus_init(), delegate_traps() and pmp_init().
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
We have now clear distinction between platform and hart features.
Modify the boot print messages to print hart specific features in
a string format.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Tested-by: Jonathan Balkind <jbalkind@cs.princeton.edu>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
As per the RISC-V specification, time value can be obtained from a time
CSR implemented in hardware or a MMIO based IP block. Qemu virt machine
already supports timer csr while CLINT provides the timer for other
platforms.
Implement a hart specific timer feature that can be detected at runtime.
As CSR based timer implementation are faster than MMIO address based, it
is always preferred over MMIO based one.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Tested-by: Jonathan Balkind <jbalkind@cs.princeton.edu>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
PMP & performance counters belong to a hart rather than a platform.
In addition to that, these features enable reading/writing from a
particular csr. Thus, they can be detected and set at runtime rather
than compile time.
Move PMP/MCOUNTEREN/SCOUNTEREN features to hart and detect them at runtime.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Tested-by: Jonathan Balkind <jbalkind@cs.princeton.edu>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
There may be some features which are hart specific rather than a platform
specific feature. Add a framework to support that.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Tested-by: Jonathan Balkind <jbalkind@cs.princeton.edu>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
There may be few common mathematics helper functions which can be used
anywhere in OpenSBI project.
Add a separate math helper function file to add these functions.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Unprivileged trap handler can be reused for any cases where the executing
code expects a trap.
Rename it to "expected" trap handler as it will be used in other cases in
future.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Tested-by: Jonathan Balkind <jbalkind@cs.princeton.edu>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
The default (usually last) PMP region provides S-mode access to
complete memory range not covered by other PMP regions.
Currently, the default PMP region is described as platform specific
PMP region which is not appropriate because all platforms need it
and default PMP region should be part of generic library.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Enable vector context in mstatus by updating the corresponding bits
in mstatus if vector extension is supported by the hart.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
This patch optimize unpriv load/store implementation by having
dedicated unpriv trap handler (just like KVM RISC-V).
As a result of this optimization:
1. We have reduced roughly 13+ instruction in all unpriv load/store
functions. The reduced instruction also include two function calls.
2. Per-HART trap info pointer in scratch space is now redundant
hence removed.
3. The sbi_trap_handler() is now much cleaner because we don't have
to handle unpriv load/store traps.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Currently pmp_get() returns the log2 length of the PMP memory
region size. The caller has to calculate the size based on that
and the same codes are duplicated.
Update this function to return decoded size directly.
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
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 <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
The sbi_hart_id_to_scratch() just forwards call to firmware specific
hartid_to_scratch() callback so we make sbi_hart_id_to_scratch() as
macro in sbi_scratch.h instead of regular function in sbi_hart.c.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
The HART available mask and related APIs are now totally redundant
because of more extensive HART state machine implemented by sbi_hsm.
Due to above, we remove HART available mask and related APIs.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
The coldboot wait APIs are only used by sbi_init.c so no point in
having coldboot related code in sbi_hart.c.
As per-above rationale, we move all coldboot wait related APIs to
sbi_init.c as static/local functions.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
This fixes various coding style issues found in the SBI codes.
No functional changes.
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
The right location for all bits related defines and macros is
sbi_bitops.h hence this patch. With this patch, the sbi_bits.h
is redundant so we remove it.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
As per the RISC-V privilege specification, WFI can be implemented as
a NOP. Software should ensure that relevant interrupt pending bits
are set. Otherwise, loop back to WFI.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
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 <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
We print MIDELEG and MEDELEG CSRs as part of boot prints so that
boot log shows the interrupts and exceptions delegated to S-mode.
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
The MIDELEG and MEDELEG CSR checks at end of delegate_traps() were
added for initial bring-up on SiFive Unleashed and QEMU. These
checks are not required any more and in-future these checks can
cause failures because some of the MIDELEG/MEDELEG bits will be
hard-wired to 0 or 1.
For related discussion, refer github issue:
https://github.com/riscv/opensbi/issues/157
Signed-off-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Atish Patra