acpi_timer.c revision 1.2.2.3
1 1.2.2.3 yamt /* $NetBSD: acpi_timer.c,v 1.2.2.3 2006/08/11 15:43:59 yamt Exp $ */ 2 1.2.2.3 yamt 3 1.2.2.3 yamt #include <sys/cdefs.h> 4 1.2.2.3 yamt __KERNEL_RCSID(0, "$NetBSD: acpi_timer.c,v 1.2.2.3 2006/08/11 15:43:59 yamt Exp $"); 5 1.2.2.2 yamt 6 1.2.2.2 yamt #include <sys/types.h> 7 1.2.2.3 yamt #include <dev/acpi/acpi_timer.h> 8 1.2.2.2 yamt 9 1.2.2.2 yamt #ifdef __HAVE_TIMECOUNTER 10 1.2.2.2 yamt 11 1.2.2.2 yamt #include <sys/systm.h> 12 1.2.2.2 yamt #include <sys/time.h> 13 1.2.2.2 yamt #include <sys/timetc.h> 14 1.2.2.2 yamt #include <dev/acpi/acpica.h> 15 1.2.2.2 yamt 16 1.2.2.3 yamt static int acpitimer_test(void); 17 1.2.2.3 yamt static uint32_t acpitimer_delta(uint32_t, uint32_t); 18 1.2.2.3 yamt static u_int acpitimer_read_safe(struct timecounter *); 19 1.2.2.3 yamt static u_int acpitimer_read_fast(struct timecounter *); 20 1.2.2.2 yamt 21 1.2.2.2 yamt static struct timecounter acpi_timecounter = { 22 1.2.2.3 yamt acpitimer_read_safe, 23 1.2.2.2 yamt 0, 24 1.2.2.2 yamt 0x00ffffff, 25 1.2.2.2 yamt PM_TIMER_FREQUENCY, 26 1.2.2.3 yamt "ACPI-Safe", 27 1.2.2.2 yamt 900 28 1.2.2.2 yamt }; 29 1.2.2.2 yamt 30 1.2.2.2 yamt int 31 1.2.2.2 yamt acpitimer_init() 32 1.2.2.2 yamt { 33 1.2.2.2 yamt uint32_t bits; 34 1.2.2.3 yamt int i, j; 35 1.2.2.2 yamt ACPI_STATUS res; 36 1.2.2.2 yamt 37 1.2.2.2 yamt res = AcpiGetTimerResolution(&bits); 38 1.2.2.2 yamt if (res != AE_OK) 39 1.2.2.2 yamt return (-1); 40 1.2.2.2 yamt 41 1.2.2.2 yamt if (bits == 32) 42 1.2.2.2 yamt acpi_timecounter.tc_counter_mask = 0xffffffff; 43 1.2.2.2 yamt 44 1.2.2.3 yamt j = 0; 45 1.2.2.3 yamt for (i = 0; i < 10; i++) 46 1.2.2.3 yamt j += acpitimer_test(); 47 1.2.2.3 yamt 48 1.2.2.3 yamt if (j >= 10) { 49 1.2.2.3 yamt acpi_timecounter.tc_name = "ACPI-Fast"; 50 1.2.2.3 yamt acpi_timecounter.tc_get_timecount = acpitimer_read_fast; 51 1.2.2.3 yamt acpi_timecounter.tc_quality = 1000; 52 1.2.2.3 yamt } 53 1.2.2.3 yamt 54 1.2.2.3 yamt tc_init(&acpi_timecounter); 55 1.2.2.3 yamt aprint_normal("%s %d-bit timer\n", acpi_timecounter.tc_name, bits); 56 1.2.2.2 yamt 57 1.2.2.2 yamt return (0); 58 1.2.2.2 yamt } 59 1.2.2.2 yamt 60 1.2.2.3 yamt static u_int 61 1.2.2.3 yamt acpitimer_read_fast(struct timecounter *tc) 62 1.2.2.3 yamt { 63 1.2.2.3 yamt uint32_t t; 64 1.2.2.3 yamt 65 1.2.2.3 yamt AcpiGetTimer(&t); 66 1.2.2.3 yamt return (t); 67 1.2.2.3 yamt } 68 1.2.2.3 yamt 69 1.2.2.2 yamt /* 70 1.2.2.2 yamt * Some chipsets (PIIX4 variants) do not latch correctly; there 71 1.2.2.2 yamt * is a chance that a transition is hit. 72 1.2.2.2 yamt */ 73 1.2.2.2 yamt static u_int 74 1.2.2.3 yamt acpitimer_read_safe(struct timecounter *tc) 75 1.2.2.2 yamt { 76 1.2.2.2 yamt uint32_t t1, t2, t3; 77 1.2.2.2 yamt 78 1.2.2.2 yamt AcpiGetTimer(&t2); 79 1.2.2.2 yamt AcpiGetTimer(&t3); 80 1.2.2.2 yamt do { 81 1.2.2.2 yamt t1 = t2; 82 1.2.2.2 yamt t2 = t3; 83 1.2.2.2 yamt AcpiGetTimer(&t3); 84 1.2.2.2 yamt } while ((t1 > t2) || (t2 > t3)); 85 1.2.2.2 yamt return (t2); 86 1.2.2.2 yamt } 87 1.2.2.2 yamt 88 1.2.2.3 yamt static uint32_t 89 1.2.2.3 yamt acpitimer_delta(uint32_t end, uint32_t start) 90 1.2.2.3 yamt { 91 1.2.2.3 yamt uint32_t delta; 92 1.2.2.3 yamt u_int mask = acpi_timecounter.tc_counter_mask; 93 1.2.2.3 yamt 94 1.2.2.3 yamt if (end >= start) 95 1.2.2.3 yamt delta = end - start; 96 1.2.2.3 yamt else 97 1.2.2.3 yamt delta = ((mask - start) + end + 1) & mask; 98 1.2.2.3 yamt 99 1.2.2.3 yamt return (delta); 100 1.2.2.3 yamt } 101 1.2.2.3 yamt 102 1.2.2.3 yamt #define N 2000 103 1.2.2.3 yamt static int 104 1.2.2.3 yamt acpitimer_test() 105 1.2.2.3 yamt { 106 1.2.2.3 yamt uint32_t last, this, delta; 107 1.2.2.3 yamt int minl, maxl, n; 108 1.2.2.3 yamt 109 1.2.2.3 yamt minl = 10000000; 110 1.2.2.3 yamt maxl = 0; 111 1.2.2.3 yamt 112 1.2.2.3 yamt disable_intr(); 113 1.2.2.3 yamt AcpiGetTimer(&last); 114 1.2.2.3 yamt for (n = 0; n < N; n++) { 115 1.2.2.3 yamt AcpiGetTimer(&this); 116 1.2.2.3 yamt delta = acpitimer_delta(this, last); 117 1.2.2.3 yamt if (delta > maxl) 118 1.2.2.3 yamt maxl = delta; 119 1.2.2.3 yamt else if (delta < minl) 120 1.2.2.3 yamt minl = delta; 121 1.2.2.3 yamt last = this; 122 1.2.2.3 yamt } 123 1.2.2.3 yamt enable_intr(); 124 1.2.2.3 yamt 125 1.2.2.3 yamt if (maxl - minl > 2 ) 126 1.2.2.3 yamt n = 0; 127 1.2.2.3 yamt else if (minl < 0 || maxl == 0) 128 1.2.2.3 yamt n = 0; 129 1.2.2.3 yamt else 130 1.2.2.3 yamt n = 1; 131 1.2.2.3 yamt 132 1.2.2.3 yamt return (n); 133 1.2.2.3 yamt } 134 1.2.2.3 yamt 135 1.2.2.2 yamt #else 136 1.2.2.2 yamt 137 1.2.2.2 yamt int 138 1.2.2.2 yamt acpitimer_init() 139 1.2.2.2 yamt { 140 1.2.2.2 yamt 141 1.2.2.2 yamt return (0); 142 1.2.2.2 yamt } 143 1.2.2.2 yamt 144 1.2.2.2 yamt #endif 145
Indexes created Fri Sep 26 08:10:20 GMT 2025