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selftests: Test the new RISC-V hwprobe interface

This adds a test for the recently added RISC-V interface for probing
hardware capabilities.  It happens to be the first selftest we have for
RISC-V, so I've added some infrastructure for those as well.

Co-developed-by: Palmer Dabbelt <palmer@rivosinc.com>
Signed-off-by: Evan Green <evan@rivosinc.com>
Link: https://lore.kernel.org/r/20230407231103.2622178-6-evan@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This commit is contained in:
Evan Green 2023-04-07 16:11:02 -07:00 committed by Palmer Dabbelt
parent 62a31d6e38
commit 287dcc2b0c
No known key found for this signature in database
GPG Key ID: 2E1319F35FBB1889
5 changed files with 171 additions and 0 deletions

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@ -63,6 +63,7 @@ TARGETS += pstore
TARGETS += ptrace
TARGETS += openat2
TARGETS += resctrl
TARGETS += riscv
TARGETS += rlimits
TARGETS += rseq
TARGETS += rtc

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@ -0,0 +1,58 @@
# SPDX-License-Identifier: GPL-2.0
# Originally tools/testing/arm64/Makefile
# When ARCH not overridden for crosscompiling, lookup machine
ARCH ?= $(shell uname -m 2>/dev/null || echo not)
ifneq (,$(filter $(ARCH),riscv))
RISCV_SUBTARGETS ?= hwprobe
else
RISCV_SUBTARGETS :=
endif
CFLAGS := -Wall -O2 -g
# A proper top_srcdir is needed by KSFT(lib.mk)
top_srcdir = $(realpath ../../../../)
# Additional include paths needed by kselftest.h and local headers
CFLAGS += -I$(top_srcdir)/tools/testing/selftests/
CFLAGS += $(KHDR_INCLUDES)
export CFLAGS
export top_srcdir
all:
@for DIR in $(RISCV_SUBTARGETS); do \
BUILD_TARGET=$(OUTPUT)/$$DIR; \
mkdir -p $$BUILD_TARGET; \
$(MAKE) OUTPUT=$$BUILD_TARGET -C $$DIR $@; \
done
install: all
@for DIR in $(RISCV_SUBTARGETS); do \
BUILD_TARGET=$(OUTPUT)/$$DIR; \
$(MAKE) OUTPUT=$$BUILD_TARGET -C $$DIR $@; \
done
run_tests: all
@for DIR in $(RISCV_SUBTARGETS); do \
BUILD_TARGET=$(OUTPUT)/$$DIR; \
$(MAKE) OUTPUT=$$BUILD_TARGET -C $$DIR $@; \
done
# Avoid any output on non riscv on emit_tests
emit_tests: all
@for DIR in $(RISCV_SUBTARGETS); do \
BUILD_TARGET=$(OUTPUT)/$$DIR; \
$(MAKE) OUTPUT=$$BUILD_TARGET -C $$DIR $@; \
done
clean:
@for DIR in $(RISCV_SUBTARGETS); do \
BUILD_TARGET=$(OUTPUT)/$$DIR; \
$(MAKE) OUTPUT=$$BUILD_TARGET -C $$DIR $@; \
done
.PHONY: all clean install run_tests emit_tests

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@ -0,0 +1,10 @@
# SPDX-License-Identifier: GPL-2.0
# Copyright (C) 2021 ARM Limited
# Originally tools/testing/arm64/abi/Makefile
TEST_GEN_PROGS := hwprobe
include ../../lib.mk
$(OUTPUT)/hwprobe: hwprobe.c sys_hwprobe.S
$(CC) -o$@ $(CFLAGS) $(LDFLAGS) $^

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@ -0,0 +1,90 @@
// SPDX-License-Identifier: GPL-2.0-only
#include <stddef.h>
#include <asm/hwprobe.h>
/*
* Rather than relying on having a new enough libc to define this, just do it
* ourselves. This way we don't need to be coupled to a new-enough libc to
* contain the call.
*/
long riscv_hwprobe(struct riscv_hwprobe *pairs, size_t pair_count,
size_t cpu_count, unsigned long *cpus, unsigned int flags);
int main(int argc, char **argv)
{
struct riscv_hwprobe pairs[8];
unsigned long cpus;
long out;
/* Fake the CPU_SET ops. */
cpus = -1;
/*
* Just run a basic test: pass enough pairs to get up to the base
* behavior, and then check to make sure it's sane.
*/
for (long i = 0; i < 8; i++)
pairs[i].key = i;
out = riscv_hwprobe(pairs, 8, 1, &cpus, 0);
if (out != 0)
return -1;
for (long i = 0; i < 4; ++i) {
/* Fail if the kernel claims not to recognize a base key. */
if ((i < 4) && (pairs[i].key != i))
return -2;
if (pairs[i].key != RISCV_HWPROBE_KEY_BASE_BEHAVIOR)
continue;
if (pairs[i].value & RISCV_HWPROBE_BASE_BEHAVIOR_IMA)
continue;
return -3;
}
/*
* This should also work with a NULL CPU set, but should not work
* with an improperly supplied CPU set.
*/
out = riscv_hwprobe(pairs, 8, 0, 0, 0);
if (out != 0)
return -4;
out = riscv_hwprobe(pairs, 8, 0, &cpus, 0);
if (out == 0)
return -5;
out = riscv_hwprobe(pairs, 8, 1, 0, 0);
if (out == 0)
return -6;
/*
* Check that keys work by providing one that we know exists, and
* checking to make sure the resultig pair is what we asked for.
*/
pairs[0].key = RISCV_HWPROBE_KEY_BASE_BEHAVIOR;
out = riscv_hwprobe(pairs, 1, 1, &cpus, 0);
if (out != 0)
return -7;
if (pairs[0].key != RISCV_HWPROBE_KEY_BASE_BEHAVIOR)
return -8;
/*
* Check that an unknown key gets overwritten with -1,
* but doesn't block elements after it.
*/
pairs[0].key = 0x5555;
pairs[1].key = 1;
pairs[1].value = 0xAAAA;
out = riscv_hwprobe(pairs, 2, 0, 0, 0);
if (out != 0)
return -9;
if (pairs[0].key != -1)
return -10;
if ((pairs[1].key != 1) || (pairs[1].value == 0xAAAA))
return -11;
return 0;
}

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@ -0,0 +1,12 @@
/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright (C) 2023 Rivos, Inc */
.text
.global riscv_hwprobe
riscv_hwprobe:
# Put __NR_riscv_hwprobe in the syscall number register, then just shim
# back the kernel's return. This doesn't do any sort of errno
# handling, the caller can deal with it.
li a7, 258
ecall
ret