acpi_timer.c revision 1.5.2.2
1 1.5.2.2 gdamore /* $NetBSD: acpi_timer.c,v 1.5.2.2 2006/07/13 17:49:17 gdamore Exp $ */ 2 1.5.2.2 gdamore 3 1.5.2.2 gdamore #include <sys/cdefs.h> 4 1.5.2.2 gdamore __KERNEL_RCSID(0, "$NetBSD: acpi_timer.c,v 1.5.2.2 2006/07/13 17:49:17 gdamore Exp $"); 5 1.5.2.2 gdamore 6 1.5.2.2 gdamore #include <sys/types.h> 7 1.5.2.2 gdamore #include <dev/acpi/acpi_timer.h> 8 1.5.2.2 gdamore 9 1.5.2.2 gdamore #ifdef __HAVE_TIMECOUNTER 10 1.5.2.2 gdamore 11 1.5.2.2 gdamore #include <sys/systm.h> 12 1.5.2.2 gdamore #include <sys/time.h> 13 1.5.2.2 gdamore #include <sys/timetc.h> 14 1.5.2.2 gdamore #include <dev/acpi/acpica.h> 15 1.5.2.2 gdamore 16 1.5.2.2 gdamore static int acpitimer_test(void); 17 1.5.2.2 gdamore static uint32_t acpitimer_delta(uint32_t, uint32_t); 18 1.5.2.2 gdamore static u_int acpitimer_read_safe(struct timecounter *); 19 1.5.2.2 gdamore static u_int acpitimer_read_fast(struct timecounter *); 20 1.5.2.2 gdamore 21 1.5.2.2 gdamore static struct timecounter acpi_timecounter = { 22 1.5.2.2 gdamore acpitimer_read_safe, 23 1.5.2.2 gdamore 0, 24 1.5.2.2 gdamore 0x00ffffff, 25 1.5.2.2 gdamore PM_TIMER_FREQUENCY, 26 1.5.2.2 gdamore "ACPI-Safe", 27 1.5.2.2 gdamore 900 28 1.5.2.2 gdamore }; 29 1.5.2.2 gdamore 30 1.5.2.2 gdamore int 31 1.5.2.2 gdamore acpitimer_init() 32 1.5.2.2 gdamore { 33 1.5.2.2 gdamore uint32_t bits; 34 1.5.2.2 gdamore int i, j; 35 1.5.2.2 gdamore ACPI_STATUS res; 36 1.5.2.2 gdamore 37 1.5.2.2 gdamore res = AcpiGetTimerResolution(&bits); 38 1.5.2.2 gdamore if (res != AE_OK) 39 1.5.2.2 gdamore return (-1); 40 1.5.2.2 gdamore 41 1.5.2.2 gdamore if (bits == 32) 42 1.5.2.2 gdamore acpi_timecounter.tc_counter_mask = 0xffffffff; 43 1.5.2.2 gdamore 44 1.5.2.2 gdamore j = 0; 45 1.5.2.2 gdamore for (i = 0; i < 10; i++) 46 1.5.2.2 gdamore j += acpitimer_test(); 47 1.5.2.2 gdamore 48 1.5.2.2 gdamore if (j >= 10) { 49 1.5.2.2 gdamore acpi_timecounter.tc_name = "ACPI-Fast"; 50 1.5.2.2 gdamore acpi_timecounter.tc_get_timecount = acpitimer_read_fast; 51 1.5.2.2 gdamore acpi_timecounter.tc_quality = 1000; 52 1.5.2.2 gdamore } 53 1.5.2.2 gdamore 54 1.5.2.2 gdamore tc_init(&acpi_timecounter); 55 1.5.2.2 gdamore aprint_normal("%s %d-bit timer\n", acpi_timecounter.tc_name, bits); 56 1.5.2.2 gdamore 57 1.5.2.2 gdamore return (0); 58 1.5.2.2 gdamore } 59 1.5.2.2 gdamore 60 1.5.2.2 gdamore static u_int 61 1.5.2.2 gdamore acpitimer_read_fast(struct timecounter *tc) 62 1.5.2.2 gdamore { 63 1.5.2.2 gdamore uint32_t t; 64 1.5.2.2 gdamore 65 1.5.2.2 gdamore AcpiGetTimer(&t); 66 1.5.2.2 gdamore return (t); 67 1.5.2.2 gdamore } 68 1.5.2.2 gdamore 69 1.5.2.2 gdamore /* 70 1.5.2.2 gdamore * Some chipsets (PIIX4 variants) do not latch correctly; there 71 1.5.2.2 gdamore * is a chance that a transition is hit. 72 1.5.2.2 gdamore */ 73 1.5.2.2 gdamore static u_int 74 1.5.2.2 gdamore acpitimer_read_safe(struct timecounter *tc) 75 1.5.2.2 gdamore { 76 1.5.2.2 gdamore uint32_t t1, t2, t3; 77 1.5.2.2 gdamore 78 1.5.2.2 gdamore AcpiGetTimer(&t2); 79 1.5.2.2 gdamore AcpiGetTimer(&t3); 80 1.5.2.2 gdamore do { 81 1.5.2.2 gdamore t1 = t2; 82 1.5.2.2 gdamore t2 = t3; 83 1.5.2.2 gdamore AcpiGetTimer(&t3); 84 1.5.2.2 gdamore } while ((t1 > t2) || (t2 > t3)); 85 1.5.2.2 gdamore return (t2); 86 1.5.2.2 gdamore } 87 1.5.2.2 gdamore 88 1.5.2.2 gdamore static uint32_t 89 1.5.2.2 gdamore acpitimer_delta(uint32_t end, uint32_t start) 90 1.5.2.2 gdamore { 91 1.5.2.2 gdamore uint32_t delta; 92 1.5.2.2 gdamore u_int mask = acpi_timecounter.tc_counter_mask; 93 1.5.2.2 gdamore 94 1.5.2.2 gdamore if (end >= start) 95 1.5.2.2 gdamore delta = end - start; 96 1.5.2.2 gdamore else 97 1.5.2.2 gdamore delta = ((mask - start) + end + 1) & mask; 98 1.5.2.2 gdamore 99 1.5.2.2 gdamore return (delta); 100 1.5.2.2 gdamore } 101 1.5.2.2 gdamore 102 1.5.2.2 gdamore #define N 2000 103 1.5.2.2 gdamore static int 104 1.5.2.2 gdamore acpitimer_test() 105 1.5.2.2 gdamore { 106 1.5.2.2 gdamore uint32_t last, this, delta; 107 1.5.2.2 gdamore int minl, maxl, n; 108 1.5.2.2 gdamore 109 1.5.2.2 gdamore minl = 10000000; 110 1.5.2.2 gdamore maxl = 0; 111 1.5.2.2 gdamore 112 1.5.2.2 gdamore disable_intr(); 113 1.5.2.2 gdamore AcpiGetTimer(&last); 114 1.5.2.2 gdamore for (n = 0; n < N; n++) { 115 1.5.2.2 gdamore AcpiGetTimer(&this); 116 1.5.2.2 gdamore delta = acpitimer_delta(this, last); 117 1.5.2.2 gdamore if (delta > maxl) 118 1.5.2.2 gdamore maxl = delta; 119 1.5.2.2 gdamore else if (delta < minl) 120 1.5.2.2 gdamore minl = delta; 121 1.5.2.2 gdamore last = this; 122 1.5.2.2 gdamore } 123 1.5.2.2 gdamore enable_intr(); 124 1.5.2.2 gdamore 125 1.5.2.2 gdamore if (maxl - minl > 2 ) 126 1.5.2.2 gdamore n = 0; 127 1.5.2.2 gdamore else if (minl < 0 || maxl == 0) 128 1.5.2.2 gdamore n = 0; 129 1.5.2.2 gdamore else 130 1.5.2.2 gdamore n = 1; 131 1.5.2.2 gdamore 132 1.5.2.2 gdamore return (n); 133 1.5.2.2 gdamore } 134 1.5.2.2 gdamore 135 1.5.2.2 gdamore #else 136 1.5.2.2 gdamore 137 1.5.2.2 gdamore int 138 1.5.2.2 gdamore acpitimer_init() 139 1.5.2.2 gdamore { 140 1.5.2.2 gdamore 141 1.5.2.2 gdamore return (0); 142 1.5.2.2 gdamore } 143 1.5.2.2 gdamore 144 1.5.2.2 gdamore #endif 145
Indexes created Fri Sep 26 08:10:20 GMT 2025