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Diffstat (limited to 'lib/librte_eal/linuxapp/eal/eal_hpet.c')
-rw-r--r--lib/librte_eal/linuxapp/eal/eal_hpet.c232
1 files changed, 232 insertions, 0 deletions
diff --git a/lib/librte_eal/linuxapp/eal/eal_hpet.c b/lib/librte_eal/linuxapp/eal/eal_hpet.c
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index 0000000..aa686b1
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+++ b/lib/librte_eal/linuxapp/eal/eal_hpet.c
@@ -0,0 +1,232 @@
+/*-
+ * BSD LICENSE
+ *
+ * Copyright(c) 2010-2012 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.
+ *
+ * version: DPDK.L.1.2.3-3
+ */
+
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <stdarg.h>
+#include <stdint.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <sys/mman.h>
+#include <sys/queue.h>
+#include <unistd.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 "eal_private.h"
+#include "eal_internal_cfg.h"
+
+#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 counter increments in femtoseconds (10^-15 seconds). */
+static uint32_t eal_hpet_resolution_fs = 0;
+
+/* Frequency of the 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 __attribute__((noreturn)) 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);
+ }
+}
+
+static inline void
+set_rdtsc_freq(void)
+{
+ uint64_t start;
+
+ start = rte_rdtsc();
+ sleep(1);
+ eal_hpet_resolution_hz = rte_rdtsc() - start;
+ eal_hpet_resolution_fs = (uint32_t)
+ ((1.0 / eal_hpet_resolution_hz) / 1e-15);
+}
+
+/*
+ * Open and mmap /dev/hpet (high precision event timer) that will
+ * provide our time reference.
+ */
+int
+rte_eal_hpet_init(void)
+{
+ int fd, ret;
+
+ if (internal_config.no_hpet) {
+ goto use_rdtsc;
+ }
+
+ fd = open(DEV_HPET, O_RDONLY);
+ if (fd < 0) {
+ RTE_LOG(WARNING, EAL, "WARNING: Cannot open "DEV_HPET": %s! "
+ "The TSC will be used instead.\n",
+ strerror(errno));
+ goto use_rdtsc;
+ }
+ eal_hpet = mmap(NULL, 1024, PROT_READ, MAP_SHARED, fd, 0);
+ if (eal_hpet == MAP_FAILED) {
+ RTE_LOG(WARNING, EAL, "WARNING: Cannot mmap "DEV_HPET"! "
+ "The TSC will be used instead.\n");
+ close(fd);
+ goto use_rdtsc;
+ }
+ 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;
+
+ 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, hpet_msb_inc, NULL);
+ if (ret < 0) {
+ RTE_LOG(WARNING, EAL, "WARNING: Cannot create HPET timer thread! "
+ "The TSC will be used instead.\n");
+ goto use_rdtsc;
+ }
+
+ return 0;
+
+use_rdtsc:
+ internal_config.no_hpet = 1;
+ set_rdtsc_freq();
+ return 0;
+}
+
+uint64_t
+rte_get_hpet_hz(void)
+{
+ return eal_hpet_resolution_hz;
+}
+
+uint64_t
+rte_get_hpet_cycles(void)
+{
+ uint32_t t, msb;
+ uint64_t ret;
+
+ if(internal_config.no_hpet)
+ /* fallback to rdtsc */
+ return rte_rdtsc();
+
+ t = eal_hpet->counter_l;
+ msb = eal_hpet_msb;
+ ret = (msb + 2 - (t >> 30)) / 4;
+ ret <<= 32;
+ ret += t;
+ return ret;
+}
+
+void
+rte_delay_us(unsigned us)
+{
+ uint64_t start;
+ uint64_t ticks;
+ ticks = (uint64_t)us * 1000ULL * 1000ULL * 1000ULL;
+ ticks /= eal_hpet_resolution_fs;
+ start = rte_get_hpet_cycles();
+ while ((rte_get_hpet_cycles() - start) < ticks)
+ rte_pause();
+}