From 42e0576eec75479fa7709c41e5c3b9ec556b8f4d Mon Sep 17 00:00:00 2001 From: Kajol Jain Date: Fri, 10 Jun 2022 19:10:39 +0530 Subject: [PATCH] selftests/powerpc/pmu: Add mask/shift bits for extracting threshold compare field In power10, threshold compare field is not part of the raw event code and provided via event attribute config1. Hence add the mask and shift bits based on event attribute config1, to extract the threshold compare value for power10 Also add a new function called get_thresh_cmp_val to compute and return the threshold compare field for a given platform, since incase of power10, threshold compare value provided is decimal. Signed-off-by: Kajol Jain Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220610134113.62991-2-atrajeev@linux.vnet.ibm.com --- .../powerpc/pmu/sampling_tests/misc.c | 44 +++++++++++++++++++ .../powerpc/pmu/sampling_tests/misc.h | 1 + 2 files changed, 45 insertions(+) diff --git a/tools/testing/selftests/powerpc/pmu/sampling_tests/misc.c b/tools/testing/selftests/powerpc/pmu/sampling_tests/misc.c index c01a31d5f4eee..b984d1e162ac4 100644 --- a/tools/testing/selftests/powerpc/pmu/sampling_tests/misc.c +++ b/tools/testing/selftests/powerpc/pmu/sampling_tests/misc.c @@ -60,6 +60,8 @@ static void init_ev_encodes(void) switch (pvr) { case POWER10: + ev_mask_thd_cmp = 0x3ffff; + ev_shift_thd_cmp = 0; ev_mask_rsq = 1; ev_shift_rsq = 9; ev_mask_comb = 3; @@ -410,3 +412,45 @@ u64 get_reg_value(u64 *intr_regs, char *register_name) return *(intr_regs + register_bit_position); } + +int get_thresh_cmp_val(struct event event) +{ + int exp = 0; + u64 result = 0; + u64 value; + + if (!have_hwcap2(PPC_FEATURE2_ARCH_3_1)) + return EV_CODE_EXTRACT(event.attr.config, thd_cmp); + + value = EV_CODE_EXTRACT(event.attr.config1, thd_cmp); + + if (!value) + return value; + + /* + * Incase of P10, thresh_cmp value is not part of raw event code + * and provided via attr.config1 parameter. To program threshold in MMCRA, + * take a 18 bit number N and shift right 2 places and increment + * the exponent E by 1 until the upper 10 bits of N are zero. + * Write E to the threshold exponent and write the lower 8 bits of N + * to the threshold mantissa. + * The max threshold that can be written is 261120. + */ + if (value > 261120) + value = 261120; + while ((64 - __builtin_clzl(value)) > 8) { + exp++; + value >>= 2; + } + + /* + * Note that it is invalid to write a mantissa with the + * upper 2 bits of mantissa being zero, unless the + * exponent is also zero. + */ + if (!(value & 0xC0) && exp) + result = -1; + else + result = (exp << 8) | value; + return result; +} diff --git a/tools/testing/selftests/powerpc/pmu/sampling_tests/misc.h b/tools/testing/selftests/powerpc/pmu/sampling_tests/misc.h index 7675f31777251..078120883fdef 100644 --- a/tools/testing/selftests/powerpc/pmu/sampling_tests/misc.h +++ b/tools/testing/selftests/powerpc/pmu/sampling_tests/misc.h @@ -52,6 +52,7 @@ void *__event_read_samples(void *sample_buff, size_t *size, u64 *sample_count); int collect_samples(void *sample_buff); u64 *get_intr_regs(struct event *event, void *sample_buff); u64 get_reg_value(u64 *intr_regs, char *register_name); +int get_thresh_cmp_val(struct event event); static inline int get_mmcr0_fc56(u64 mmcr0, int pmc) { -- 2.30.2