linux/tools/testing/selftests/powerpc/dscr/dscr_user_test.c
Anshuman Khandual cc6a93f1c3 selftests/powerpc: Add test for DSCR SPR numbers
This patch adds a test which verifies that the DSCR privilege and
problem state SPR read & write accesses while making sure that the
results are always the same irrespective of which SPR number is being
used.

Acked-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-06-07 19:36:51 +10:00

62 lines
1.5 KiB
C

/*
* 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.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published
* by the Free Software Foundation.
*/
#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;
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");
}