Current Debug Trigger SBI extension proposal suggests to activate
shmem area and obtain its physical address from S-mode software
in the following way:
: If both `shmem_phys_lo` and `shmem_phys_hi` parameters are not
: all-ones bitwise then `shmem_phys_lo` specifies the lower XLEN
: bits and `shmem_phys_hi` specifies the upper XLEN bits of the
: shared memory physical base address. The `shmem_phys_lo` MUST
: be `(XLEN / 8)` byte aligned and the size of shared memory is
: assumed to be `trig_max * (XLEN / 2)` bytes.
For more details see the current version of the proposal:
- https://lists.riscv.org/g/tech-debug/message/1302
On the other hand, on RV32, the M-mode can only access the first 4GB of
the physical address space because M-mode does not have MMU to access
full 34-bit physical address space. Similarly, on RV64, the M-mode can
only access memory addressed by 64 bits.
This commit checks shmem address in function sbi_dbtr_setup_shmem
to make sure that shmem_phys_hi part of the valid address is zero.
Besides, the macro DBTR_SHMEM_MAKE_PHYS is updated to take into
account only low XLEN part.
Signed-off-by: Sergey Matyukevich <geomatsi@gmail.com>
Reviewed-by: Himanshu Chauhan <hchauhan@ventanamicro.com>
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>
