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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /tools/testing/selftests/powerpc/dscr
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/testing/selftests/powerpc/dscr')
-rw-r--r--tools/testing/selftests/powerpc/dscr/.gitignore8
-rw-r--r--tools/testing/selftests/powerpc/dscr/Makefile13
-rw-r--r--tools/testing/selftests/powerpc/dscr/dscr.h122
-rw-r--r--tools/testing/selftests/powerpc/dscr/dscr_default_test.c126
-rw-r--r--tools/testing/selftests/powerpc/dscr/dscr_explicit_test.c70
-rw-r--r--tools/testing/selftests/powerpc/dscr/dscr_inherit_exec_test.c108
-rw-r--r--tools/testing/selftests/powerpc/dscr/dscr_inherit_test.c86
-rw-r--r--tools/testing/selftests/powerpc/dscr/dscr_sysfs_test.c103
-rw-r--r--tools/testing/selftests/powerpc/dscr/dscr_sysfs_thread_test.c79
-rw-r--r--tools/testing/selftests/powerpc/dscr/dscr_user_test.c60
-rw-r--r--tools/testing/selftests/powerpc/dscr/settings1
11 files changed, 776 insertions, 0 deletions
diff --git a/tools/testing/selftests/powerpc/dscr/.gitignore b/tools/testing/selftests/powerpc/dscr/.gitignore
new file mode 100644
index 000000000..1d08b15af
--- /dev/null
+++ b/tools/testing/selftests/powerpc/dscr/.gitignore
@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: GPL-2.0-only
+dscr_default_test
+dscr_explicit_test
+dscr_inherit_exec_test
+dscr_inherit_test
+dscr_sysfs_test
+dscr_sysfs_thread_test
+dscr_user_test
diff --git a/tools/testing/selftests/powerpc/dscr/Makefile b/tools/testing/selftests/powerpc/dscr/Makefile
new file mode 100644
index 000000000..845db6273
--- /dev/null
+++ b/tools/testing/selftests/powerpc/dscr/Makefile
@@ -0,0 +1,13 @@
+# SPDX-License-Identifier: GPL-2.0
+TEST_GEN_PROGS := dscr_default_test dscr_explicit_test dscr_user_test \
+ dscr_inherit_test dscr_inherit_exec_test dscr_sysfs_test \
+ dscr_sysfs_thread_test
+
+TEST_FILES := settings
+
+top_srcdir = ../../../../..
+include ../../lib.mk
+
+$(OUTPUT)/dscr_default_test: LDLIBS += -lpthread
+
+$(TEST_GEN_PROGS): ../harness.c ../utils.c
diff --git a/tools/testing/selftests/powerpc/dscr/dscr.h b/tools/testing/selftests/powerpc/dscr/dscr.h
new file mode 100644
index 000000000..13e9b9e28
--- /dev/null
+++ b/tools/testing/selftests/powerpc/dscr/dscr.h
@@ -0,0 +1,122 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * POWER Data Stream Control Register (DSCR)
+ *
+ * This header file contains helper functions and macros
+ * required for all the DSCR related test cases.
+ *
+ * Copyright 2012, Anton Blanchard, IBM Corporation.
+ * Copyright 2015, Anshuman Khandual, IBM Corporation.
+ */
+#ifndef _SELFTESTS_POWERPC_DSCR_DSCR_H
+#define _SELFTESTS_POWERPC_DSCR_DSCR_H
+
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <fcntl.h>
+#include <dirent.h>
+#include <pthread.h>
+#include <sched.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/wait.h>
+
+#include "utils.h"
+
+#define THREADS 100 /* Max threads */
+#define COUNT 100 /* Max iterations */
+#define DSCR_MAX 16 /* Max DSCR value */
+#define LEN_MAX 100 /* Max name length */
+
+#define DSCR_DEFAULT "/sys/devices/system/cpu/dscr_default"
+#define CPU_PATH "/sys/devices/system/cpu/"
+
+#define rmb() asm volatile("lwsync":::"memory")
+#define wmb() asm volatile("lwsync":::"memory")
+
+#define READ_ONCE(x) (*(volatile typeof(x) *)&(x))
+
+/* Prilvilege state DSCR access */
+inline unsigned long get_dscr(void)
+{
+ unsigned long ret;
+
+ asm volatile("mfspr %0,%1" : "=r" (ret) : "i" (SPRN_DSCR_PRIV));
+
+ return ret;
+}
+
+inline void set_dscr(unsigned long val)
+{
+ asm volatile("mtspr %1,%0" : : "r" (val), "i" (SPRN_DSCR_PRIV));
+}
+
+/* Problem state DSCR access */
+inline unsigned long get_dscr_usr(void)
+{
+ unsigned long ret;
+
+ asm volatile("mfspr %0,%1" : "=r" (ret) : "i" (SPRN_DSCR));
+
+ return ret;
+}
+
+inline void set_dscr_usr(unsigned long val)
+{
+ asm volatile("mtspr %1,%0" : : "r" (val), "i" (SPRN_DSCR));
+}
+
+/* Default DSCR access */
+unsigned long get_default_dscr(void)
+{
+ int fd = -1, ret;
+ char buf[16];
+ unsigned long val;
+
+ if (fd == -1) {
+ fd = open(DSCR_DEFAULT, O_RDONLY);
+ if (fd == -1) {
+ perror("open() failed");
+ exit(1);
+ }
+ }
+ memset(buf, 0, sizeof(buf));
+ lseek(fd, 0, SEEK_SET);
+ ret = read(fd, buf, sizeof(buf));
+ if (ret == -1) {
+ perror("read() failed");
+ exit(1);
+ }
+ sscanf(buf, "%lx", &val);
+ close(fd);
+ return val;
+}
+
+void set_default_dscr(unsigned long val)
+{
+ int fd = -1, ret;
+ char buf[16];
+
+ if (fd == -1) {
+ fd = open(DSCR_DEFAULT, O_RDWR);
+ if (fd == -1) {
+ perror("open() failed");
+ exit(1);
+ }
+ }
+ sprintf(buf, "%lx\n", val);
+ ret = write(fd, buf, strlen(buf));
+ if (ret == -1) {
+ perror("write() failed");
+ exit(1);
+ }
+ close(fd);
+}
+
+double uniform_deviate(int seed)
+{
+ return seed * (1.0 / (RAND_MAX + 1.0));
+}
+#endif /* _SELFTESTS_POWERPC_DSCR_DSCR_H */
diff --git a/tools/testing/selftests/powerpc/dscr/dscr_default_test.c b/tools/testing/selftests/powerpc/dscr/dscr_default_test.c
new file mode 100644
index 000000000..e76611e60
--- /dev/null
+++ b/tools/testing/selftests/powerpc/dscr/dscr_default_test.c
@@ -0,0 +1,126 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * POWER Data Stream Control Register (DSCR) default test
+ *
+ * This test modifies the system wide default DSCR through
+ * it's sysfs interface and then verifies that all threads
+ * see the correct changed DSCR value immediately.
+ *
+ * Copyright 2012, Anton Blanchard, IBM Corporation.
+ * Copyright 2015, Anshuman Khandual, IBM Corporation.
+ */
+#include "dscr.h"
+
+static unsigned long dscr; /* System DSCR default */
+static unsigned long sequence;
+static unsigned long result[THREADS];
+
+static void *do_test(void *in)
+{
+ unsigned long thread = (unsigned long)in;
+ unsigned long i;
+
+ for (i = 0; i < COUNT; i++) {
+ unsigned long d, cur_dscr, cur_dscr_usr;
+ unsigned long s1, s2;
+
+ s1 = READ_ONCE(sequence);
+ if (s1 & 1)
+ continue;
+ rmb();
+
+ d = dscr;
+ cur_dscr = get_dscr();
+ cur_dscr_usr = get_dscr_usr();
+
+ rmb();
+ s2 = sequence;
+
+ if (s1 != s2)
+ continue;
+
+ if (cur_dscr != d) {
+ fprintf(stderr, "thread %ld kernel DSCR should be %ld "
+ "but is %ld\n", thread, d, cur_dscr);
+ result[thread] = 1;
+ pthread_exit(&result[thread]);
+ }
+
+ if (cur_dscr_usr != d) {
+ fprintf(stderr, "thread %ld user DSCR should be %ld "
+ "but is %ld\n", thread, d, cur_dscr_usr);
+ result[thread] = 1;
+ pthread_exit(&result[thread]);
+ }
+ }
+ result[thread] = 0;
+ pthread_exit(&result[thread]);
+}
+
+int dscr_default(void)
+{
+ pthread_t threads[THREADS];
+ unsigned long i, *status[THREADS];
+ unsigned long orig_dscr_default;
+
+ SKIP_IF(!have_hwcap2(PPC_FEATURE2_DSCR));
+
+ orig_dscr_default = get_default_dscr();
+
+ /* Initial DSCR default */
+ dscr = 1;
+ set_default_dscr(dscr);
+
+ /* Spawn all testing threads */
+ for (i = 0; i < THREADS; i++) {
+ if (pthread_create(&threads[i], NULL, do_test, (void *)i)) {
+ perror("pthread_create() failed");
+ goto fail;
+ }
+ }
+
+ srand(getpid());
+
+ /* Keep changing the DSCR default */
+ for (i = 0; i < COUNT; i++) {
+ double ret = uniform_deviate(rand());
+
+ if (ret < 0.0001) {
+ sequence++;
+ wmb();
+
+ dscr++;
+ if (dscr > DSCR_MAX)
+ dscr = 0;
+
+ set_default_dscr(dscr);
+
+ wmb();
+ sequence++;
+ }
+ }
+
+ /* Individual testing thread exit status */
+ for (i = 0; i < THREADS; i++) {
+ if (pthread_join(threads[i], (void **)&(status[i]))) {
+ perror("pthread_join() failed");
+ goto fail;
+ }
+
+ if (*status[i]) {
+ printf("%ldth thread failed to join with %ld status\n",
+ i, *status[i]);
+ goto fail;
+ }
+ }
+ set_default_dscr(orig_dscr_default);
+ return 0;
+fail:
+ set_default_dscr(orig_dscr_default);
+ return 1;
+}
+
+int main(int argc, char *argv[])
+{
+ return test_harness(dscr_default, "dscr_default_test");
+}
diff --git a/tools/testing/selftests/powerpc/dscr/dscr_explicit_test.c b/tools/testing/selftests/powerpc/dscr/dscr_explicit_test.c
new file mode 100644
index 000000000..32fcf2b32
--- /dev/null
+++ b/tools/testing/selftests/powerpc/dscr/dscr_explicit_test.c
@@ -0,0 +1,70 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * POWER Data Stream Control Register (DSCR) explicit test
+ *
+ * This test modifies the DSCR value using mtspr instruction and
+ * verifies the change with mfspr instruction. It uses both the
+ * privilege state SPR and the problem state SPR for this purpose.
+ *
+ * When using the privilege state SPR, the instructions such as
+ * mfspr or mtspr are priviledged and the kernel emulates them
+ * for us. Instructions using problem state SPR can be exuecuted
+ * directly without any emulation if the HW supports them. Else
+ * they also get emulated by the kernel.
+ *
+ * Copyright 2012, Anton Blanchard, IBM Corporation.
+ * Copyright 2015, Anshuman Khandual, IBM Corporation.
+ */
+#include "dscr.h"
+
+int dscr_explicit(void)
+{
+ unsigned long i, dscr = 0;
+
+ SKIP_IF(!have_hwcap2(PPC_FEATURE2_DSCR));
+
+ srand(getpid());
+ set_dscr(dscr);
+
+ for (i = 0; i < COUNT; i++) {
+ unsigned long cur_dscr, cur_dscr_usr;
+ double ret = uniform_deviate(rand());
+
+ if (ret < 0.001) {
+ dscr++;
+ if (dscr > DSCR_MAX)
+ dscr = 0;
+
+ set_dscr(dscr);
+ }
+
+ cur_dscr = get_dscr();
+ if (cur_dscr != dscr) {
+ fprintf(stderr, "Kernel DSCR should be %ld but "
+ "is %ld\n", dscr, cur_dscr);
+ return 1;
+ }
+
+ ret = uniform_deviate(rand());
+ if (ret < 0.001) {
+ dscr++;
+ if (dscr > DSCR_MAX)
+ dscr = 0;
+
+ set_dscr_usr(dscr);
+ }
+
+ cur_dscr_usr = get_dscr_usr();
+ if (cur_dscr_usr != dscr) {
+ fprintf(stderr, "User DSCR should be %ld but "
+ "is %ld\n", dscr, cur_dscr_usr);
+ return 1;
+ }
+ }
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ return test_harness(dscr_explicit, "dscr_explicit_test");
+}
diff --git a/tools/testing/selftests/powerpc/dscr/dscr_inherit_exec_test.c b/tools/testing/selftests/powerpc/dscr/dscr_inherit_exec_test.c
new file mode 100644
index 000000000..c6a81b2d6
--- /dev/null
+++ b/tools/testing/selftests/powerpc/dscr/dscr_inherit_exec_test.c
@@ -0,0 +1,108 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * POWER Data Stream Control Register (DSCR) fork exec test
+ *
+ * This testcase modifies the DSCR using mtspr, forks & execs and
+ * verifies that the child is using the changed DSCR using mfspr.
+ *
+ * When using the privilege state SPR, the instructions such as
+ * mfspr or mtspr are privileged and the kernel emulates them
+ * for us. Instructions using problem state SPR can be executed
+ * directly without any emulation if the HW supports them. Else
+ * they also get emulated by the kernel.
+ *
+ * Copyright 2012, Anton Blanchard, IBM Corporation.
+ * Copyright 2015, Anshuman Khandual, IBM Corporation.
+ */
+#include "dscr.h"
+
+static char *prog;
+
+static void do_exec(unsigned long parent_dscr)
+{
+ unsigned long cur_dscr, cur_dscr_usr;
+
+ cur_dscr = get_dscr();
+ cur_dscr_usr = get_dscr_usr();
+
+ if (cur_dscr != parent_dscr) {
+ fprintf(stderr, "Parent DSCR %ld was not inherited "
+ "over exec (kernel value)\n", parent_dscr);
+ exit(1);
+ }
+
+ if (cur_dscr_usr != parent_dscr) {
+ fprintf(stderr, "Parent DSCR %ld was not inherited "
+ "over exec (user value)\n", parent_dscr);
+ exit(1);
+ }
+ exit(0);
+}
+
+int dscr_inherit_exec(void)
+{
+ unsigned long i, dscr = 0;
+ pid_t pid;
+
+ SKIP_IF(!have_hwcap2(PPC_FEATURE2_DSCR));
+
+ for (i = 0; i < COUNT; i++) {
+ dscr++;
+ if (dscr > DSCR_MAX)
+ dscr = 0;
+
+ if (dscr == get_default_dscr())
+ continue;
+
+ if (i % 2 == 0)
+ set_dscr_usr(dscr);
+ else
+ set_dscr(dscr);
+
+ pid = fork();
+ if (pid == -1) {
+ perror("fork() failed");
+ exit(1);
+ } else if (pid) {
+ int status;
+
+ if (waitpid(pid, &status, 0) == -1) {
+ perror("waitpid() failed");
+ exit(1);
+ }
+
+ if (!WIFEXITED(status)) {
+ fprintf(stderr, "Child didn't exit cleanly\n");
+ exit(1);
+ }
+
+ if (WEXITSTATUS(status) != 0) {
+ fprintf(stderr, "Child didn't exit cleanly\n");
+ return 1;
+ }
+ } else {
+ char dscr_str[16];
+
+ sprintf(dscr_str, "%ld", dscr);
+ execlp(prog, prog, "exec", dscr_str, NULL);
+ exit(1);
+ }
+ }
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ if (argc == 3 && !strcmp(argv[1], "exec")) {
+ unsigned long parent_dscr;
+
+ parent_dscr = atoi(argv[2]);
+ do_exec(parent_dscr);
+ } else if (argc != 1) {
+ fprintf(stderr, "Usage: %s\n", argv[0]);
+ exit(1);
+ }
+
+ prog = argv[0];
+ return test_harness(dscr_inherit_exec, "dscr_inherit_exec_test");
+}
diff --git a/tools/testing/selftests/powerpc/dscr/dscr_inherit_test.c b/tools/testing/selftests/powerpc/dscr/dscr_inherit_test.c
new file mode 100644
index 000000000..f9dfd3d3c
--- /dev/null
+++ b/tools/testing/selftests/powerpc/dscr/dscr_inherit_test.c
@@ -0,0 +1,86 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * POWER Data Stream Control Register (DSCR) fork test
+ *
+ * This testcase modifies the DSCR using mtspr, forks and then
+ * verifies that the child process has the correct changed DSCR
+ * value using mfspr.
+ *
+ * When using the privilege state SPR, the instructions such as
+ * mfspr or mtspr are priviledged and the kernel emulates them
+ * for us. Instructions using problem state SPR can be exuecuted
+ * directly without any emulation if the HW supports them. Else
+ * they also get emulated by the kernel.
+ *
+ * Copyright 2012, Anton Blanchard, IBM Corporation.
+ * Copyright 2015, Anshuman Khandual, IBM Corporation.
+ */
+#include "dscr.h"
+
+int dscr_inherit(void)
+{
+ unsigned long i, dscr = 0;
+ pid_t pid;
+
+ SKIP_IF(!have_hwcap2(PPC_FEATURE2_DSCR));
+
+ srand(getpid());
+ set_dscr(dscr);
+
+ for (i = 0; i < COUNT; i++) {
+ unsigned long cur_dscr, cur_dscr_usr;
+
+ dscr++;
+ if (dscr > DSCR_MAX)
+ dscr = 0;
+
+ if (i % 2 == 0)
+ set_dscr_usr(dscr);
+ else
+ set_dscr(dscr);
+
+ pid = fork();
+ if (pid == -1) {
+ perror("fork() failed");
+ exit(1);
+ } else if (pid) {
+ int status;
+
+ if (waitpid(pid, &status, 0) == -1) {
+ perror("waitpid() failed");
+ exit(1);
+ }
+
+ if (!WIFEXITED(status)) {
+ fprintf(stderr, "Child didn't exit cleanly\n");
+ exit(1);
+ }
+
+ if (WEXITSTATUS(status) != 0) {
+ fprintf(stderr, "Child didn't exit cleanly\n");
+ return 1;
+ }
+ } else {
+ cur_dscr = get_dscr();
+ if (cur_dscr != dscr) {
+ fprintf(stderr, "Kernel DSCR should be %ld "
+ "but is %ld\n", dscr, cur_dscr);
+ exit(1);
+ }
+
+ cur_dscr_usr = get_dscr_usr();
+ if (cur_dscr_usr != dscr) {
+ fprintf(stderr, "User DSCR should be %ld "
+ "but is %ld\n", dscr, cur_dscr_usr);
+ exit(1);
+ }
+ exit(0);
+ }
+ }
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ return test_harness(dscr_inherit, "dscr_inherit_test");
+}
diff --git a/tools/testing/selftests/powerpc/dscr/dscr_sysfs_test.c b/tools/testing/selftests/powerpc/dscr/dscr_sysfs_test.c
new file mode 100644
index 000000000..f20d1c166
--- /dev/null
+++ b/tools/testing/selftests/powerpc/dscr/dscr_sysfs_test.c
@@ -0,0 +1,103 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * POWER Data Stream Control Register (DSCR) sysfs interface test
+ *
+ * This test updates to system wide DSCR default through the sysfs interface
+ * and then verifies that all the CPU specific DSCR defaults are updated as
+ * well verified from their sysfs interfaces.
+ *
+ * Copyright 2015, Anshuman Khandual, IBM Corporation.
+ */
+#include "dscr.h"
+
+static int check_cpu_dscr_default(char *file, unsigned long val)
+{
+ char buf[10];
+ int fd, rc;
+
+ fd = open(file, O_RDWR);
+ if (fd == -1) {
+ perror("open() failed");
+ return 1;
+ }
+
+ rc = read(fd, buf, sizeof(buf));
+ if (rc == -1) {
+ perror("read() failed");
+ close(fd);
+ return 1;
+ }
+ close(fd);
+
+ buf[rc] = '\0';
+ if (strtol(buf, NULL, 16) != val) {
+ printf("DSCR match failed: %ld (system) %ld (cpu)\n",
+ val, strtol(buf, NULL, 16));
+ return 1;
+ }
+ return 0;
+}
+
+static int check_all_cpu_dscr_defaults(unsigned long val)
+{
+ DIR *sysfs;
+ struct dirent *dp;
+ char file[LEN_MAX];
+
+ sysfs = opendir(CPU_PATH);
+ if (!sysfs) {
+ perror("opendir() failed");
+ return 1;
+ }
+
+ while ((dp = readdir(sysfs))) {
+ int len;
+
+ if (!(dp->d_type & DT_DIR))
+ continue;
+ if (!strcmp(dp->d_name, "cpuidle"))
+ continue;
+ if (!strstr(dp->d_name, "cpu"))
+ continue;
+
+ len = snprintf(file, LEN_MAX, "%s%s/dscr", CPU_PATH, dp->d_name);
+ if (len >= LEN_MAX)
+ continue;
+ if (access(file, F_OK))
+ continue;
+
+ if (check_cpu_dscr_default(file, val)) {
+ closedir(sysfs);
+ return 1;
+ }
+ }
+ closedir(sysfs);
+ return 0;
+}
+
+int dscr_sysfs(void)
+{
+ unsigned long orig_dscr_default;
+ int i, j;
+
+ SKIP_IF(!have_hwcap2(PPC_FEATURE2_DSCR));
+
+ orig_dscr_default = get_default_dscr();
+ for (i = 0; i < COUNT; i++) {
+ for (j = 0; j < DSCR_MAX; j++) {
+ set_default_dscr(j);
+ if (check_all_cpu_dscr_defaults(j))
+ goto fail;
+ }
+ }
+ set_default_dscr(orig_dscr_default);
+ return 0;
+fail:
+ set_default_dscr(orig_dscr_default);
+ return 1;
+}
+
+int main(int argc, char *argv[])
+{
+ return test_harness(dscr_sysfs, "dscr_sysfs_test");
+}
diff --git a/tools/testing/selftests/powerpc/dscr/dscr_sysfs_thread_test.c b/tools/testing/selftests/powerpc/dscr/dscr_sysfs_thread_test.c
new file mode 100644
index 000000000..191ed126f
--- /dev/null
+++ b/tools/testing/selftests/powerpc/dscr/dscr_sysfs_thread_test.c
@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * POWER Data Stream Control Register (DSCR) sysfs thread test
+ *
+ * This test updates the system wide DSCR default value through
+ * sysfs interface which should then update all the CPU specific
+ * DSCR default values which must also be then visible to threads
+ * executing on individual CPUs on the system.
+ *
+ * Copyright 2015, Anshuman Khandual, IBM Corporation.
+ */
+#define _GNU_SOURCE
+#include "dscr.h"
+
+static int test_thread_dscr(unsigned long val)
+{
+ unsigned long cur_dscr, cur_dscr_usr;
+
+ cur_dscr = get_dscr();
+ cur_dscr_usr = get_dscr_usr();
+
+ if (val != cur_dscr) {
+ printf("[cpu %d] Kernel DSCR should be %ld but is %ld\n",
+ sched_getcpu(), val, cur_dscr);
+ return 1;
+ }
+
+ if (val != cur_dscr_usr) {
+ printf("[cpu %d] User DSCR should be %ld but is %ld\n",
+ sched_getcpu(), val, cur_dscr_usr);
+ return 1;
+ }
+ return 0;
+}
+
+static int check_cpu_dscr_thread(unsigned long val)
+{
+ cpu_set_t mask;
+ int cpu;
+
+ for (cpu = 0; cpu < CPU_SETSIZE; cpu++) {
+ CPU_ZERO(&mask);
+ CPU_SET(cpu, &mask);
+ if (sched_setaffinity(0, sizeof(mask), &mask))
+ continue;
+
+ if (test_thread_dscr(val))
+ return 1;
+ }
+ return 0;
+
+}
+
+int dscr_sysfs_thread(void)
+{
+ unsigned long orig_dscr_default;
+ int i, j;
+
+ SKIP_IF(!have_hwcap2(PPC_FEATURE2_DSCR));
+
+ orig_dscr_default = get_default_dscr();
+ for (i = 0; i < COUNT; i++) {
+ for (j = 0; j < DSCR_MAX; j++) {
+ set_default_dscr(j);
+ if (check_cpu_dscr_thread(j))
+ goto fail;
+ }
+ }
+ set_default_dscr(orig_dscr_default);
+ return 0;
+fail:
+ set_default_dscr(orig_dscr_default);
+ return 1;
+}
+
+int main(int argc, char *argv[])
+{
+ return test_harness(dscr_sysfs_thread, "dscr_sysfs_thread_test");
+}
diff --git a/tools/testing/selftests/powerpc/dscr/dscr_user_test.c b/tools/testing/selftests/powerpc/dscr/dscr_user_test.c
new file mode 100644
index 000000000..e09072446
--- /dev/null
+++ b/tools/testing/selftests/powerpc/dscr/dscr_user_test.c
@@ -0,0 +1,60 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * POWER Data Stream Control Register (DSCR) SPR test
+ *
+ * This test modifies the DSCR value through both the SPR number
+ * based mtspr instruction and then makes sure that the same is
+ * reflected through mfspr instruction using either of the SPR
+ * numbers.
+ *
+ * When using the privilege state SPR, the instructions such as
+ * mfspr or mtspr are priviledged and the kernel emulates them
+ * for us. Instructions using problem state SPR can be exuecuted
+ * directly without any emulation if the HW supports them. Else
+ * they also get emulated by the kernel.
+ *
+ * Copyright 2013, Anton Blanchard, IBM Corporation.
+ * Copyright 2015, Anshuman Khandual, IBM Corporation.
+ */
+#include "dscr.h"
+
+static int check_dscr(char *str)
+{
+ unsigned long cur_dscr, cur_dscr_usr;
+
+ cur_dscr = get_dscr();
+ cur_dscr_usr = get_dscr_usr();
+ if (cur_dscr != cur_dscr_usr) {
+ printf("%s set, kernel get %lx != user get %lx\n",
+ str, cur_dscr, cur_dscr_usr);
+ return 1;
+ }
+ return 0;
+}
+
+int dscr_user(void)
+{
+ int i;
+
+ SKIP_IF(!have_hwcap2(PPC_FEATURE2_DSCR));
+
+ check_dscr("");
+
+ for (i = 0; i < COUNT; i++) {
+ set_dscr(i);
+ if (check_dscr("kernel"))
+ return 1;
+ }
+
+ for (i = 0; i < COUNT; i++) {
+ set_dscr_usr(i);
+ if (check_dscr("user"))
+ return 1;
+ }
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ return test_harness(dscr_user, "dscr_user_test");
+}
diff --git a/tools/testing/selftests/powerpc/dscr/settings b/tools/testing/selftests/powerpc/dscr/settings
new file mode 100644
index 000000000..e7b941753
--- /dev/null
+++ b/tools/testing/selftests/powerpc/dscr/settings
@@ -0,0 +1 @@
+timeout=0