--- /dev/null
+/*-
+ * BSD LICENSE
+ *
+ * Copyright(c) 2010-2013 Intel Corporation. All rights reserved.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * * Neither the name of Intel Corporation nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <sys/mman.h>
+#include <sys/queue.h>
+#include <pthread.h>
+#include <errno.h>
+
+#include <rte_common.h>
+#include <rte_log.h>
+#include <rte_cycles.h>
+#include <rte_tailq.h>
+#include <rte_memory.h>
+#include <rte_memzone.h>
+#include <rte_eal.h>
+#include <rte_debug.h>
+
+#include "eal_private.h"
+#include "eal_internal_cfg.h"
+
+enum timer_source eal_timer_source = EAL_TIMER_HPET;
+
+/* The frequency of the RDTSC timer resolution */
+static uint64_t eal_tsc_resolution_hz = 0;
+
+#ifdef RTE_LIBEAL_USE_HPET
+
+#define DEV_HPET "/dev/hpet"
+
+/* Maximum number of counters. */
+#define HPET_TIMER_NUM 3
+
+/* General capabilities register */
+#define CLK_PERIOD_SHIFT 32 /* Clock period shift. */
+#define CLK_PERIOD_MASK 0xffffffff00000000ULL /* Clock period mask. */
+#define COUNT_SIZE_CAP_SHIFT 13 /* Count size capa. shift. */
+#define COUNT_SIZE_CAP_MASK 0x0000000000002000ULL /* Count size capa. mask. */
+
+/**
+ * HPET timer registers. From the Intel IA-PC HPET (High Precision Event
+ * Timers) Specification.
+ */
+struct eal_hpet_regs {
+ /* Memory-mapped, software visible registers */
+ uint64_t capabilities; /**< RO General Capabilities Register. */
+ uint64_t reserved0; /**< Reserved for future use. */
+ uint64_t config; /**< RW General Configuration Register. */
+ uint64_t reserved1; /**< Reserved for future use. */
+ uint64_t isr; /**< RW Clear General Interrupt Status. */
+ uint64_t reserved2[25]; /**< Reserved for future use. */
+ union {
+ uint64_t counter; /**< RW Main Counter Value Register. */
+ struct {
+ uint32_t counter_l; /**< RW Main Counter Low. */
+ uint32_t counter_h; /**< RW Main Counter High. */
+ };
+ };
+ uint64_t reserved3; /**< Reserved for future use. */
+ struct {
+ uint64_t config; /**< RW Timer Config and Capability Reg. */
+ uint64_t comp; /**< RW Timer Comparator Value Register. */
+ uint64_t fsb; /**< RW FSB Interrupt Route Register. */
+ uint64_t reserved4; /**< Reserved for future use. */
+ } timers[HPET_TIMER_NUM]; /**< Set of HPET timers. */
+};
+
+/* Mmap'd hpet registers */
+static volatile struct eal_hpet_regs *eal_hpet = NULL;
+
+/* Period at which the HPET counter increments in
+ * femtoseconds (10^-15 seconds). */
+static uint32_t eal_hpet_resolution_fs = 0;
+
+/* Frequency of the HPET counter in Hz */
+static uint64_t eal_hpet_resolution_hz = 0;
+
+/* Incremented 4 times during one 32bits hpet full count */
+static uint32_t eal_hpet_msb;
+
+static pthread_t msb_inc_thread_id;
+
+/*
+ * This function runs on a specific thread to update a global variable
+ * containing used to process MSB of the HPET (unfortunatelly, we need
+ * this because hpet is 32 bits by default under linux).
+ */
+static void
+hpet_msb_inc(__attribute__((unused)) void *arg)
+{
+ uint32_t t;
+
+ while (1) {
+ t = (eal_hpet->counter_l >> 30);
+ if (t != (eal_hpet_msb & 3))
+ eal_hpet_msb ++;
+ sleep(10);
+ }
+}
+
+uint64_t
+rte_get_hpet_hz(void)
+{
+ if(internal_config.no_hpet)
+ rte_panic("Error, HPET called, but no HPET present\n");
+
+ return eal_hpet_resolution_hz;
+}
+
+uint64_t
+rte_get_hpet_cycles(void)
+{
+ uint32_t t, msb;
+ uint64_t ret;
+
+ if(internal_config.no_hpet)
+ rte_panic("Error, HPET called, but no HPET present\n");
+
+ t = eal_hpet->counter_l;
+ msb = eal_hpet_msb;
+ ret = (msb + 2 - (t >> 30)) / 4;
+ ret <<= 32;
+ ret += t;
+ return ret;
+}
+
+#endif
+
+
+void
+rte_delay_us(unsigned us)
+{
+ const uint64_t start = rte_get_timer_cycles();
+ const uint64_t ticks = (uint64_t)us * rte_get_timer_hz() / 1E6;
+ while ((rte_get_timer_cycles() - start) < ticks)
+ rte_pause();
+}
+
+uint64_t
+rte_get_tsc_hz(void)
+{
+ return eal_tsc_resolution_hz;
+}
+
+
+#ifdef RTE_LIBEAL_USE_HPET
+/*
+ * Open and mmap /dev/hpet (high precision event timer) that will
+ * provide our time reference.
+ */
+int
+rte_eal_hpet_init(int make_default)
+{
+ int fd, ret;
+
+ if (internal_config.no_hpet) {
+ RTE_LOG(INFO, EAL, "HPET is disabled\n");
+ return -1;
+ }
+
+ fd = open(DEV_HPET, O_RDONLY);
+ if (fd < 0) {
+ RTE_LOG(ERR, EAL, "ERROR: Cannot open "DEV_HPET": %s!\n",
+ strerror(errno));
+ internal_config.no_hpet = 1;
+ return -1;
+ }
+ eal_hpet = mmap(NULL, 1024, PROT_READ, MAP_SHARED, fd, 0);
+ if (eal_hpet == MAP_FAILED) {
+ RTE_LOG(ERR, EAL, "ERROR: Cannot mmap "DEV_HPET"!\n"
+ "Please enable CONFIG_HPET_MMAP in your kernel configuration "
+ "to allow HPET support.\n"
+ "To run without using HPET, set CONFIG_RTE_LIBEAL_USE_HPET=n "
+ "in your build configuration or use '--no-hpet' EAL flag.\n");
+ close(fd);
+ internal_config.no_hpet = 1;
+ return -1;
+ }
+ close(fd);
+
+ eal_hpet_resolution_fs = (uint32_t)((eal_hpet->capabilities &
+ CLK_PERIOD_MASK) >>
+ CLK_PERIOD_SHIFT);
+
+ eal_hpet_resolution_hz = (1000ULL*1000ULL*1000ULL*1000ULL*1000ULL) /
+ (uint64_t)eal_hpet_resolution_fs;
+
+ RTE_LOG(INFO, EAL, "HPET frequency is ~%"PRIu64" kHz\n",
+ eal_hpet_resolution_hz/1000);
+
+ eal_hpet_msb = (eal_hpet->counter_l >> 30);
+
+ /* create a thread that will increment a global variable for
+ * msb (hpet is 32 bits by default under linux) */
+ ret = pthread_create(&msb_inc_thread_id, NULL,
+ (void *(*)(void *))hpet_msb_inc, NULL);
+ if (ret < 0) {
+ RTE_LOG(ERR, EAL, "ERROR: Cannot create HPET timer thread!\n");
+ internal_config.no_hpet = 1;
+ return -1;
+ }
+
+ if (make_default)
+ eal_timer_source = EAL_TIMER_HPET;
+ return 0;
+}
+#endif
+
+static int
+set_tsc_freq_from_clock(void)
+{
+#ifdef CLOCK_MONOTONIC_RAW
+#define NS_PER_SEC 1E9
+
+ struct timespec sleeptime = {.tv_nsec = 5E8 }; /* 1/2 second */
+
+ struct timespec t_start, t_end;
+
+ if (clock_gettime(CLOCK_MONOTONIC_RAW, &t_start) == 0) {
+ uint64_t ns, end, start = rte_rdtsc();
+ nanosleep(&sleeptime,NULL);
+ clock_gettime(CLOCK_MONOTONIC_RAW, &t_end);
+ end = rte_rdtsc();
+ ns = ((t_end.tv_sec - t_start.tv_sec) * NS_PER_SEC);
+ ns += (t_end.tv_nsec - t_start.tv_nsec);
+
+ double secs = (double)ns/NS_PER_SEC;
+ eal_tsc_resolution_hz = (uint64_t)((end - start)/secs);
+ return 0;
+ }
+#endif
+ return -1;
+}
+
+static void
+set_tsc_freq_fallback(void)
+{
+ RTE_LOG(WARNING, EAL, "WARNING: clock_gettime cannot use "
+ "CLOCK_MONOTONIC_RAW and HPET is not available"
+ " - clock timings may be less accurate.\n");
+ /* assume that the sleep(1) will sleep for 1 second */
+ uint64_t start = rte_rdtsc();
+ sleep(1);
+ eal_tsc_resolution_hz = rte_rdtsc() - start;
+}
+/*
+ * This function measures the TSC frequency. It uses a variety of approaches.
+ *
+ * 1. If kernel provides CLOCK_MONOTONIC_RAW we use that to tune the TSC value
+ * 2. If kernel does not provide that, and we have HPET support, tune using HPET
+ * 3. Lastly, if neither of the above can be used, just sleep for 1 second and
+ * tune off that, printing a warning about inaccuracy of timing
+ */
+static void
+set_tsc_freq(void)
+{
+ if (set_tsc_freq_from_clock() < 0)
+ set_tsc_freq_fallback();
+
+ RTE_LOG(INFO, EAL, "TSC frequency is ~%"PRIu64" KHz\n",
+ eal_tsc_resolution_hz/1000);
+}
+
+int
+rte_eal_timer_init(void)
+{
+
+ eal_timer_source = EAL_TIMER_TSC;
+
+ set_tsc_freq();
+ return 0;
+}
git.droids-corp.org / dpdk.git / blobdiff