LXR linux/tools/testing/selftests/powerpc/pmu/ebb/regs_access_pmccext

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright 2021, Athira Rajeev, IBM Corp.
   4 */
   5
   6#include <stdio.h>
   7#include <stdlib.h>
   8#include <setjmp.h>
   9#include <signal.h>
  10
  11#include "ebb.h"
  12
  13
  14/*
  15 * Test that closing the EBB event clears MMCR0_PMCC and
  16 * sets MMCR0_PMCCEXT preventing further read access to the
  17 * group B PMU registers.
  18 */
  19
  20static int regs_access_pmccext(void)
  21{
  22        struct event event;
  23
  24        SKIP_IF(!ebb_is_supported());
  25
  26        event_init_named(&event, 0x1001e, "cycles");
  27        event_leader_ebb_init(&event);
  28
  29        FAIL_IF(event_open(&event));
  30
  31        ebb_enable_pmc_counting(1);
  32        setup_ebb_handler(standard_ebb_callee);
  33        ebb_global_enable();
  34        FAIL_IF(ebb_event_enable(&event));
  35
  36        mtspr(SPRN_PMC1, pmc_sample_period(sample_period));
  37
  38        while (ebb_state.stats.ebb_count < 1)
  39                FAIL_IF(core_busy_loop());
  40
  41        ebb_global_disable();
  42        event_close(&event);
  43
  44        FAIL_IF(ebb_state.stats.ebb_count == 0);
  45
  46        /*
  47         * For ISA v3.1, verify the test takes a SIGILL when reading
  48         * PMU regs after the event is closed. With the control bit
  49         * in MMCR0 (PMCCEXT) restricting access to group B PMU regs,
  50         * sigill is expected.
  51         */
  52        if (have_hwcap2(PPC_FEATURE2_ARCH_3_1))
  53                FAIL_IF(catch_sigill(dump_ebb_state));
  54        else
  55                dump_ebb_state();
  56
  57        return 0;
  58}
  59
  60int main(void)
  61{
  62        return test_harness(regs_access_pmccext, "regs_access_pmccext");
  63}
  64