As-per SBI specification, all firmware counters are always 64 bits
wide so let us update the SBI PMU implementation to reflect this fact.
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
The "read a firmware counter" SBI call should only work for firmware
counters so let us replace sbi_pmu_ctr_read() with sbi_pmu_ctr_fw_read()
which works only on firmware counters.
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
fw_event_map represents array of firmware events. It should initialized
for maximum number of firmware events not counters.
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
The active_events array is accessed with counter ID passed from the supervisor
software before the counter ID bound check. This may cause a buffer overrun
if a supervisor passes an invalid counter ID.
Fix this by moving the access part after the bound check.
Reported-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Currently, there is no sanity check for firmware event code. We don't see
any issue as Linux kernel driver does a bound check on firmware events
already. However, OpenSBI can't assume sane supervisor mode software
always. Thus, an invalid event idx can cause a buffer overflow error.
For hardware events, the match will fail for invalid event code anyways.
However, a search is unecessary if event code is invalid.
Add a event ID validation function to solve the issue.
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
The current implementation computes the possible counter range
by doing a left shift of counter base. However, this may overflow depending
on the counter base value. In case of overflow, the highest counter id
may be computed incorrectly. As per the SBI specification, the respective
function should return an error if any of the counter is not valid.
Fix the counter index check by avoiding left shifting while doing the
sanity checks. Without the shift, the implementation just iterates
over the counter mask and computes the correct counter index by adding
the base to it.
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
OpenSBI explicitly assumes that there is no pmu hardware counter with
index 1: hardware uses that bit for TM control. So OpenSBI filters
out that index in sanity checks. However OpenSBI also excludes that
counter when reports total amount of hardware counters to Linux. As
a result, Linux uses incomplete counters mask excluding the highest
available counter.
Return accurate number of counters, update the firmware counter
starting index, fix range checks that include num_hw_ctrs.
The simple test is to make sure that there is no counter multiplexing
in the following command:
$ perf stat -e \
r8000000000000000,r8000000000000001,r8000000000000002,r8000000000000003, \
r8000000000000004,r8000000000000005,r8000000000000006,r8000000000000007, \
r8000000000000008,r8000000000000009,r800000000000000a,r800000000000000b, \
r800000000000000c,r800000000000000d,r800000000000000e,r800000000000000f \
ls
Note that 16 firmware events with 16 counters won't require multiplexing.
Signed-off-by: Sergey Matyukevich <geomatsi@gmail.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Since past few years, we have been using "hart features" in OpenSBI
to represent all optionalities and multi-letter extensions defined
by the RISC-V specifications.
The RISC-V profiles specification has taken a different approach and
started assigning extension names for all optionalities which did not
have any extension name previously.
(Refer, https://github.com/riscv/riscv-profiles/blob/main/profiles.adoc)
Inspired from the RISC-V profiles specification, we convert OpenSBI
hart features into hart extensions. Going forward, we align the
extension naming with RISC-V profiles specification. Currently, only
"time CSR" and "AIA CSR" have not been assigned extension name but
for everything else we have a name.
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
If a hart implements privileged spec v1.11 (or higher) then we can
safely assume that mcountinhibit CSR is present and we don't need
MCOUNTINHIBT as a hart feature.
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
If a hart implements privileged spec v1.10 (or higher) then we can
safely assume that [m|s]counteren CSR are present and we don't need
MCOUNTEREN and SCOUNTEREN as hart features.
Signed-off-by: Anup Patel <apatel@ventanamicro.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
MHPMEVENT3H-31H are defined in sscofpmf extension. Thus, they should be
accessed only if sscofpmf is present.
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
In a systems that provide strings.h and it is included
together with sbi_bitops.h the compilation error appears.
The ffs() and fls() are provided by strings.h
Signed-off-by: Petro Karashchenko <petro.karashchenko@gmail.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
PMU overflow interrupt should be disabled durinig initial configuration of
counters. They should be enabled while starting counters.
Fixes: 730f01bb41 ("lib: sbi: Support sscofpmf extension in OpenSBI")
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
The counter mapping in DT may be incorrect if all the counters specified
in the mapping are actually not physically present in the hardware.
OpenSBI should only keep a mapping of counters enabled in hardware and
defined in DT. This assume that all the programmable hpmcounters are
consecutive as it doesn't make sense to build a system with sparse
hpmcounters.
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
We should check if SSCOF extension is present,
before applying inhibit mask and clearing overflow,
otherwise undesirable value can be written
in MHPMEVENT_N CSR.
Signed-off-by: Nikita Shubin <n.shubin@yadro.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>
RISC-V privilege specification does not specify how to encode the event ID.
Therefore, each platform is allowed to customize its own encoding rule.
The common encoding methods are as follow, directly assigning a number to an
event, or every bit in the mphmevent CSR controls one specified event or
mixes the above two methods.
To enable OpenSBI to support the above three encoding methods simultaneously,
this patch repurpose the dt property "riscv,raw-event-to-mhpmcounters". The
"riscv,raw-event-to-mhpmcounters" will describes the one or multiple raw
events that could be counted by a set of counters. But, the column number
of "riscv,raw-event-to-mhpmcounters" is extended from 2 to 3. The 1st column
(64bit) is the ID of the raw events. The 2nd column (64bit) represents a
select_mask now to represent the bits used for event ID encoding.
If a platform directly encodes each raw PMU event as a unique ID,
the value of select_mask will be 0xffffffff_ffffffff.
Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Signed-off-by: Atish Patra<atishp@rivosinc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
A recent commit (b28f0700) turns to read from CSR_MCOUNTINHIBIT after
checking the SBI_HART_HAS_MCOUNTINHIBIT HART feature, which leaves the
mctr_inhbt uninitialized in pmu_ctr_find_hw().
As a result, compiler will complain:
error: 'mctr_inhbt' may be used uninitialized in this function.
This commit resolves the issue by assigning an initial value to mctr_inhbt.
Signed-off-by: Dong Du <Dd_nirvana@sjtu.edu.cn>
Reviewed-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Some platforms such as hifive unmatched doesn't implement mcountinhibit
csr. However, it has hardware events that can be monitored using 2
hpmcounter it has (i.e. mhpmcounter3 & mhpmcounter4).
Currently, PMU extension disabled if mcountinhibit is absent. That's not
really necessary as long as the supervisor OS keeps track of the delta
value of the counters. Without mcountinhibit, the delta value won't be
entirely accurate because the counters are freely running. However, that
should be fine to produce an approximate counter value which can help
performance analysis. Perf sampling won't work though as sscof extension
is not present in hifive unmatched.
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
The mhpm bits represent the number of bits available in mhpmcounter
while counter width describes a zero indexed value. Fix the counter width
calculation.
Fixes: 13d40f21d5 ("lib: sbi: Add PMU support")
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
The hardware solely relies on the event selector value in mhpmevent
to figure out what event to monitor using that counter. It should be
reset when counter reset happens.
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
A platform may use programmable counters for cycle/instret events.
The priv spec allows that provided that cycle/instret also report those
events in addition to the programmable counters. We should allow that
functionality in OpenSBI.
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
OpenSBI doesn't use any counters for its own usage. Thus, all the counters
can be made accessible for lower privilege mode always. However, the
mcountinhibit must be set so that the counter doesn't increment.
As a result, we don't have to enable/disable mcounteren at every start/stop.
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
This patch adds sscofpmf extension in pmu module which includes
following things.
1. Enable overflow irq when starting a counter.
2. Setting the correct event filters passed from supervisor.
3. Delegating the overflow interrupt to the supervisor.
4. Add RV32 support for sscofpmf.
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
The sbi_pmu_exit() crashes on systems not having MCOUNTINHIBIT csr
so to fix this we check SBI_HART_HAS_MCOUNTINHIBIT feature in
sbi_pmu_exit() and do nothing if it is not available.
Fixes: 13d40f21d5 ("lib: sbi: Add PMU support")
Signed-off-by: Anup Patel <anup.patel@wdc.com>
RISC-V SBI specfication 0.3 defines a PMU extension that allows supervisor
mode to start/stop/configure pmu related events. This patch implements
all of the functionality defined in the specification.
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
RISC-V SBI v0.3 specification defined a PMU extension to configure/start/stop
the hardware/firmware pmu events.
Implement PMU support in OpenSBI library. The implementation is agnostic of
event to counter mapping & mhpmevent value configuration. That means, it
expects platform hooks will be used to set up the mapping and provide
the mhpmevent value at runtime.
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Signed-off-by: Atish Patra <atish.patra@wdc.com>
