RISC-V: selftests: cbo: Ensure asm operands match constraints, take 2

Commit 0de65288d75f ("RISC-V: selftests: cbo: Ensure asm operands
match constraints") attempted to ensure MK_CBO() would always
provide to a compile-time constant when given a constant, but
cpu_to_le32() isn't necessarily going to do that. Switch to manually
shifting the bytes, when needed, to finally get this right.

Reported-by: Woodrow Shen <woodrow.shen@sifive.com>
Closes: https://lore.kernel.org/all/CABquHATcBTUwfLpd9sPObBgNobqQKEAZ2yxk+TWSpyO5xvpXpg@mail.gmail.com/
Fixes: a29e2a48afe3 ("RISC-V: selftests: Add CBO tests")
Fixes: 0de65288d75f ("RISC-V: selftests: cbo: Ensure asm operands match constraints")
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20240322134728.151255-2-ajones@ventanamicro.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

RISC-V: selftests: cbo: Ensure asm operands match constraints

The 'i' constraint expects a constant operand, which fn and its
constant derivative MK_CBO(fn) are, but passing fn through a function
as a parameter and using a local variable for MK_CBO(fn) allow the
compiler to lose sight of that when no optimization is done. Use
a macro instead of a function and skip the local variable to ensure
the compiler uses constants, matching the asm constraints.

Reported-by: Yunhui Cui <cuiyunhui@bytedance.com>
Closes: https://lore.kernel.org/all/20240117082514.42967-1-cuiyunhui@bytedance.com
Fixes: a29e2a48afe3 ("RISC-V: selftests: Add CBO tests")
Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20240117130933.57514-2-ajones@ventanamicro.com
Cc: stable@vger.kernel.org
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

tools: selftests: riscv: Fix compile warnings in cbo

GCC prints a couple of format string warnings when compiling
the cbo test. Let's follow the recommendation in
Documentation/printk-formats.txt to fix these warnings.

Signed-off-by: Christoph Müllner <christoph.muellner@vrull.eu>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20231123185821.2272504-3-christoph.muellner@vrull.eu
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

RISC-V: selftests: Add CBO tests

Add hwprobe test for Zicboz and its block size. Also, when Zicboz is
present, test that cbo.zero may be issued and works. Additionally
provide a command line option that enables testing that the Zicbom
instructions cause SIGILL and also that cbo.zero causes SIGILL when
Zicboz it's not present. The SIGILL tests require "opt-in" with a
command line option because the RISC-V ISA does not require
unimplemented standard opcodes to issue illegal-instruction
exceptions (but hopefully most platforms do).

Pinning the test to a subset of cpus with taskset will also restrict
the hwprobe calls to that set.

Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
Reviewed-by: Xiao Wang <xiao.w.wang@intel.com>
Link: https://lore.kernel.org/r/20230918131518.56803-14-ajones@ventanamicro.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>