acpi_timer.c revision 1.6.4.2
1 1.6.4.2 rpaulo /* $NetBSD: acpi_timer.c,v 1.6.4.2 2006/09/09 02:49:29 rpaulo Exp $ */ 2 1.6.4.2 rpaulo 3 1.6.4.2 rpaulo #include <sys/cdefs.h> 4 1.6.4.2 rpaulo __KERNEL_RCSID(0, "$NetBSD: acpi_timer.c,v 1.6.4.2 2006/09/09 02:49:29 rpaulo Exp $"); 5 1.6.4.2 rpaulo 6 1.6.4.2 rpaulo #include <sys/types.h> 7 1.6.4.2 rpaulo #include <dev/acpi/acpi_timer.h> 8 1.6.4.2 rpaulo 9 1.6.4.2 rpaulo #ifdef __HAVE_TIMECOUNTER 10 1.6.4.2 rpaulo 11 1.6.4.2 rpaulo #include <sys/systm.h> 12 1.6.4.2 rpaulo #include <sys/time.h> 13 1.6.4.2 rpaulo #include <sys/timetc.h> 14 1.6.4.2 rpaulo #include <dev/acpi/acpica.h> 15 1.6.4.2 rpaulo 16 1.6.4.2 rpaulo static int acpitimer_test(void); 17 1.6.4.2 rpaulo static uint32_t acpitimer_delta(uint32_t, uint32_t); 18 1.6.4.2 rpaulo static u_int acpitimer_read_safe(struct timecounter *); 19 1.6.4.2 rpaulo static u_int acpitimer_read_fast(struct timecounter *); 20 1.6.4.2 rpaulo 21 1.6.4.2 rpaulo static struct timecounter acpi_timecounter = { 22 1.6.4.2 rpaulo acpitimer_read_safe, 23 1.6.4.2 rpaulo 0, 24 1.6.4.2 rpaulo 0x00ffffff, 25 1.6.4.2 rpaulo PM_TIMER_FREQUENCY, 26 1.6.4.2 rpaulo "ACPI-Safe", 27 1.6.4.2 rpaulo 900, 28 1.6.4.2 rpaulo NULL, 29 1.6.4.2 rpaulo NULL, 30 1.6.4.2 rpaulo }; 31 1.6.4.2 rpaulo 32 1.6.4.2 rpaulo int 33 1.6.4.2 rpaulo acpitimer_init() 34 1.6.4.2 rpaulo { 35 1.6.4.2 rpaulo uint32_t bits; 36 1.6.4.2 rpaulo int i, j; 37 1.6.4.2 rpaulo ACPI_STATUS res; 38 1.6.4.2 rpaulo 39 1.6.4.2 rpaulo res = AcpiGetTimerResolution(&bits); 40 1.6.4.2 rpaulo if (res != AE_OK) 41 1.6.4.2 rpaulo return (-1); 42 1.6.4.2 rpaulo 43 1.6.4.2 rpaulo if (bits == 32) 44 1.6.4.2 rpaulo acpi_timecounter.tc_counter_mask = 0xffffffff; 45 1.6.4.2 rpaulo 46 1.6.4.2 rpaulo j = 0; 47 1.6.4.2 rpaulo for (i = 0; i < 10; i++) 48 1.6.4.2 rpaulo j += acpitimer_test(); 49 1.6.4.2 rpaulo 50 1.6.4.2 rpaulo if (j >= 10) { 51 1.6.4.2 rpaulo acpi_timecounter.tc_name = "ACPI-Fast"; 52 1.6.4.2 rpaulo acpi_timecounter.tc_get_timecount = acpitimer_read_fast; 53 1.6.4.2 rpaulo acpi_timecounter.tc_quality = 1000; 54 1.6.4.2 rpaulo } 55 1.6.4.2 rpaulo 56 1.6.4.2 rpaulo tc_init(&acpi_timecounter); 57 1.6.4.2 rpaulo aprint_normal("%s %d-bit timer\n", acpi_timecounter.tc_name, bits); 58 1.6.4.2 rpaulo 59 1.6.4.2 rpaulo return (0); 60 1.6.4.2 rpaulo } 61 1.6.4.2 rpaulo 62 1.6.4.2 rpaulo static u_int 63 1.6.4.2 rpaulo acpitimer_read_fast(struct timecounter *tc) 64 1.6.4.2 rpaulo { 65 1.6.4.2 rpaulo uint32_t t; 66 1.6.4.2 rpaulo 67 1.6.4.2 rpaulo AcpiGetTimer(&t); 68 1.6.4.2 rpaulo return (t); 69 1.6.4.2 rpaulo } 70 1.6.4.2 rpaulo 71 1.6.4.2 rpaulo /* 72 1.6.4.2 rpaulo * Some chipsets (PIIX4 variants) do not latch correctly; there 73 1.6.4.2 rpaulo * is a chance that a transition is hit. 74 1.6.4.2 rpaulo */ 75 1.6.4.2 rpaulo static u_int 76 1.6.4.2 rpaulo acpitimer_read_safe(struct timecounter *tc) 77 1.6.4.2 rpaulo { 78 1.6.4.2 rpaulo uint32_t t1, t2, t3; 79 1.6.4.2 rpaulo 80 1.6.4.2 rpaulo AcpiGetTimer(&t2); 81 1.6.4.2 rpaulo AcpiGetTimer(&t3); 82 1.6.4.2 rpaulo do { 83 1.6.4.2 rpaulo t1 = t2; 84 1.6.4.2 rpaulo t2 = t3; 85 1.6.4.2 rpaulo AcpiGetTimer(&t3); 86 1.6.4.2 rpaulo } while ((t1 > t2) || (t2 > t3)); 87 1.6.4.2 rpaulo return (t2); 88 1.6.4.2 rpaulo } 89 1.6.4.2 rpaulo 90 1.6.4.2 rpaulo static uint32_t 91 1.6.4.2 rpaulo acpitimer_delta(uint32_t end, uint32_t start) 92 1.6.4.2 rpaulo { 93 1.6.4.2 rpaulo uint32_t delta; 94 1.6.4.2 rpaulo u_int mask = acpi_timecounter.tc_counter_mask; 95 1.6.4.2 rpaulo 96 1.6.4.2 rpaulo if (end >= start) 97 1.6.4.2 rpaulo delta = end - start; 98 1.6.4.2 rpaulo else 99 1.6.4.2 rpaulo delta = ((mask - start) + end + 1) & mask; 100 1.6.4.2 rpaulo 101 1.6.4.2 rpaulo return (delta); 102 1.6.4.2 rpaulo } 103 1.6.4.2 rpaulo 104 1.6.4.2 rpaulo #define N 2000 105 1.6.4.2 rpaulo static int 106 1.6.4.2 rpaulo acpitimer_test() 107 1.6.4.2 rpaulo { 108 1.6.4.2 rpaulo uint32_t last, this, delta; 109 1.6.4.2 rpaulo int minl, maxl, n; 110 1.6.4.2 rpaulo 111 1.6.4.2 rpaulo minl = 10000000; 112 1.6.4.2 rpaulo maxl = 0; 113 1.6.4.2 rpaulo 114 1.6.4.2 rpaulo disable_intr(); 115 1.6.4.2 rpaulo AcpiGetTimer(&last); 116 1.6.4.2 rpaulo for (n = 0; n < N; n++) { 117 1.6.4.2 rpaulo AcpiGetTimer(&this); 118 1.6.4.2 rpaulo delta = acpitimer_delta(this, last); 119 1.6.4.2 rpaulo if (delta > maxl) 120 1.6.4.2 rpaulo maxl = delta; 121 1.6.4.2 rpaulo else if (delta < minl) 122 1.6.4.2 rpaulo minl = delta; 123 1.6.4.2 rpaulo last = this; 124 1.6.4.2 rpaulo } 125 1.6.4.2 rpaulo enable_intr(); 126 1.6.4.2 rpaulo 127 1.6.4.2 rpaulo if (maxl - minl > 2 ) 128 1.6.4.2 rpaulo n = 0; 129 1.6.4.2 rpaulo else if (minl < 0 || maxl == 0) 130 1.6.4.2 rpaulo n = 0; 131 1.6.4.2 rpaulo else 132 1.6.4.2 rpaulo n = 1; 133 1.6.4.2 rpaulo 134 1.6.4.2 rpaulo return (n); 135 1.6.4.2 rpaulo } 136 1.6.4.2 rpaulo 137 1.6.4.2 rpaulo #else 138 1.6.4.2 rpaulo 139 1.6.4.2 rpaulo int 140 1.6.4.2 rpaulo acpitimer_init() 141 1.6.4.2 rpaulo { 142 1.6.4.2 rpaulo 143 1.6.4.2 rpaulo return (0); 144 1.6.4.2 rpaulo } 145 1.6.4.2 rpaulo 146 1.6.4.2 rpaulo #endif 147
Indexes created Fri Sep 26 08:10:20 GMT 2025