root / lab2 / src / timer.c @ 227
History | View | Annotate | Download (4.11 KB)
| 1 | 196 | up20180642 | #include <lcom/lcf.h> |
|---|---|---|---|
| 2 | |||
| 3 | #include "timer.h" |
||
| 4 | |||
| 5 | #include "i8254.h" |
||
| 6 | #include "utils.h" |
||
| 7 | #include "errors.h" |
||
| 8 | |||
| 9 | //7.1 timer_test_read_config()
|
||
| 10 | int (timer_get_conf)(uint8_t timer, uint8_t *st) {
|
||
| 11 | if(st == NULL) return 1; |
||
| 12 | // Write read-back command to TIMER_CTRL
|
||
| 13 | u32_t cmd = TIMER_RB_CMD | TIMER_RB_COUNT_ | TIMER_RB_SEL(timer); |
||
| 14 | if(sys_outb(TIMER_CTRL, cmd)) return 1; |
||
| 15 | int read_port;
|
||
| 16 | switch(timer) {
|
||
| 17 | case 0: read_port = TIMER_0; break; |
||
| 18 | case 1: read_port = TIMER_1; break; |
||
| 19 | case 2: read_port = TIMER_2; break; |
||
| 20 | default: return 1; |
||
| 21 | } |
||
| 22 | if(util_sys_inb(read_port, st)) return 1; |
||
| 23 | return 0; |
||
| 24 | } |
||
| 25 | int (timer_display_conf)(uint8_t timer, uint8_t st, enum timer_status_field field) { |
||
| 26 | union timer_status_field_val conf;
|
||
| 27 | uint8_t in_mode; |
||
| 28 | switch(field){
|
||
| 29 | case tsf_all:
|
||
| 30 | conf.byte = st; /* Full Status Byte */
|
||
| 31 | break;
|
||
| 32 | case tsf_initial:
|
||
| 33 | /* Counter Initial Value Loading Mode */
|
||
| 34 | in_mode = (st & TIMER_INMODE_MASK) >> TIMER_INMODE_POS; |
||
| 35 | switch(in_mode){
|
||
| 36 | case 0: conf.in_mode = INVAL_val ; break; //000 |
||
| 37 | case 1: conf.in_mode = LSB_only ; break; //001 |
||
| 38 | case 2: conf.in_mode = MSB_only ; break; //010 |
||
| 39 | case 3: conf.in_mode = MSB_after_LSB; break; //011 |
||
| 40 | default: return 1; |
||
| 41 | } |
||
| 42 | break;
|
||
| 43 | case tsf_mode:
|
||
| 44 | /* Counting Mode */
|
||
| 45 | conf.count_mode = (st & TIMER_MODE_MASK)>>TIMER_MODE_POS; |
||
| 46 | if(conf.count_mode == TIMER_MODE_2ALT || conf.count_mode == TIMER_MODE_3ALT)
|
||
| 47 | conf.count_mode &= TIMER_MODE_RED2; |
||
| 48 | break;
|
||
| 49 | case tsf_base:
|
||
| 50 | /* Representation of Counter Initial Value */
|
||
| 51 | conf.bcd = st & TIMER_BCD; |
||
| 52 | break;
|
||
| 53 | default: return 1; |
||
| 54 | } |
||
| 55 | if(timer_print_config(timer, field, conf)) return 1; |
||
| 56 | return 0; |
||
| 57 | } |
||
| 58 | //7.2 timer_test_time_base()
|
||
| 59 | int (timer_set_frequency)(uint8_t timer, uint32_t freq) {
|
||
| 60 | |||
| 61 | // Frequencies out this range are not supported (by limitation of hardware)
|
||
| 62 | if (freq > TIMER_FREQ || freq < TIMER_MIN_FREQ) {
|
||
| 63 | printf("%s: Frequency out of range, must be between %d and %d.\n", __func__, TIMER_MIN_FREQ, TIMER_FREQ);
|
||
| 64 | return 1; |
||
| 65 | } |
||
| 66 | |||
| 67 | uint8_t status = 0;
|
||
| 68 | if (timer_get_conf(timer, &status)) return 1; |
||
| 69 | //Make command
|
||
| 70 | uint8_t write_cmd = 0;
|
||
| 71 | //Select timer
|
||
| 72 | switch(timer) {
|
||
| 73 | case 0: write_cmd |= TIMER_SEL0; break; |
||
| 74 | case 1: write_cmd |= TIMER_SEL1; break; |
||
| 75 | case 2: write_cmd |= TIMER_SEL2; break; |
||
| 76 | default: return 1; |
||
| 77 | } |
||
| 78 | //Change both LSB and MSB
|
||
| 79 | write_cmd |= TIMER_LSB_MSB; |
||
| 80 | //Keep 4 least significant bits
|
||
| 81 | write_cmd |= (status & (TIMER_MODE_MASK | TIMER_BCD)); |
||
| 82 | //Write cmd
|
||
| 83 | if (sys_outb(TIMER_CTRL, write_cmd)) return 1; |
||
| 84 | |||
| 85 | // counter_init = clock/freq
|
||
| 86 | uint16_t counter_init = (uint16_t)(TIMER_FREQ / freq); |
||
| 87 | |||
| 88 | int timer_port = 0; |
||
| 89 | switch(timer) {
|
||
| 90 | case 0: timer_port = TIMER_0; break; |
||
| 91 | case 1: timer_port = TIMER_1; break; |
||
| 92 | case 2: timer_port = TIMER_2; break; |
||
| 93 | default: return 1; |
||
| 94 | } |
||
| 95 | uint8_t lsb = 0, msb = 0; |
||
| 96 | /* Split the 16 bits word in two bytes */
|
||
| 97 | if (util_get_LSB(counter_init, &lsb)) return 1; |
||
| 98 | if (util_get_MSB(counter_init, &msb)) return 1; |
||
| 99 | |||
| 100 | /* Write the 8 LSB of the counter */
|
||
| 101 | if (sys_outb(timer_port, lsb)) return 1; |
||
| 102 | /* Write the 8 MSB of the counter */
|
||
| 103 | if (sys_outb(timer_port, msb)) return 1; |
||
| 104 | |||
| 105 | return 0; |
||
| 106 | } |
||
| 107 | //7.3 timer_test_int()
|
||
| 108 | void (timer_int_handler)(void) { |
||
| 109 | no_interrupts++; |
||
| 110 | } |
||
| 111 | #ifdef LAB2
|
||
| 112 | static int hook_id; |
||
| 113 | int (timer_subscribe_int)(uint8_t *bit_no) {
|
||
| 114 | if(bit_no == NULL) return NULL_PTR; |
||
| 115 | hook_id = 2;
|
||
| 116 | *bit_no = hook_id; |
||
| 117 | return sys_irqsetpolicy(TIMER0_IRQ, IRQ_REENABLE, &hook_id);
|
||
| 118 | } |
||
| 119 | int (timer_unsubscribe_int)() {
|
||
| 120 | return unsubscribe_interrupt(&hook_id);
|
||
| 121 | } |
||
| 122 | #endif
|
||
| 123 | int (subscribe_timer_interrupt)(uint8_t interrupt_bit, int *interrupt_id) { |
||
| 124 | if (interrupt_id == NULL) return 1; |
||
| 125 | *interrupt_id = interrupt_bit; |
||
| 126 | return (sys_irqsetpolicy(TIMER0_IRQ, IRQ_REENABLE, interrupt_id));
|
||
| 127 | } |
||
| 128 | uint32_t no_interrupts = 0; |