// 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"); }