root / proj / src / uart.c @ 237
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| 1 | 235 | up20180642 | #include <lcom/lcf.h> |
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| 2 | |||
| 3 | #include "uart.h" |
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| 4 | |||
| 5 | #include "errors.h" |
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| 6 | |||
| 7 | int uart_get_config(int base_addr, uart_config *config){ |
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| 8 | int ret = SUCCESS;
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| 9 | |||
| 10 | config->base_addr = base_addr; |
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| 11 | |||
| 12 | if((ret = util_sys_inb(base_addr+UART_LCR, &config->config))) return ret; |
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| 13 | |||
| 14 | if((ret = uart_enable_divisor_latch(base_addr))) return ret; |
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| 15 | if((ret = util_sys_inb(base_addr+UART_DLL, &config->dll ))) return ret; |
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| 16 | if((ret = util_sys_inb(base_addr+UART_DLM, &config->dlm ))) return ret; |
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| 17 | |||
| 18 | uart_parse_config(config); |
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| 19 | return ret;
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| 20 | } |
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| 21 | void uart_parse_config(uart_config *config){
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| 22 | config->bits_per_char = UART_GET_BITS_PER_CHAR(config->config); |
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| 23 | config->stop_bits = UART_GET_STOP_BITS (config->config); |
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| 24 | config->parity = UART_GET_PARITY (config->config); |
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| 25 | config->break_control = UART_GET_BREAK_CONTROL(config->config); |
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| 26 | config->divisor_latch = config->dlm<<8 | config->dll;
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| 27 | } |
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| 28 | void uart_print_config(uart_config config){
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| 29 | printf("Base address: 0x%X\n", config.base_addr);
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| 30 | printf("Configuration: 0x%02X\n", config.config);
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| 31 | printf("Number of bits per char: %d\n", config.bits_per_char);
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| 32 | printf("Number of stop bits: %d\n", config.stop_bits);
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| 33 | printf("Parity: ");
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| 34 | if((config.parity&1) == 0) printf("no parity\n"); |
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| 35 | else switch(config.parity){ |
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| 36 | case uart_parity_odd : printf("odd parity\n" ); break; |
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| 37 | case uart_parity_even: printf("even parity\n" ); break; |
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| 38 | case uart_parity_par1: printf("parity bit is 1\n"); break; |
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| 39 | case uart_parity_par0: printf("parity bit is 0\n"); break; |
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| 40 | default : printf("invalid\n" ); break; |
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| 41 | } |
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| 42 | printf("Break control: %d\n", config.break_control);
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| 43 | printf("Divisor latch: %d\n", config.divisor_latch);
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| 44 | printf("Bit rate (x1000): %d\n", 1000*(uint32_t)UART_BITRATE/config.divisor_latch); |
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| 45 | } |
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| 46 | |||
| 47 | int uart_enable_divisor_latch(int base_addr){ |
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| 48 | int ret = SUCCESS;
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| 49 | uint8_t conf; if((ret = util_sys_inb(base_addr+UART_LCR, &conf))) return ret; |
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| 50 | return uart_write_config(base_addr, conf | UART_DLAB);
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| 51 | } |
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| 52 | int uart_disable_divisor_latch(int base_addr){ |
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| 53 | int ret = SUCCESS;
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| 54 | uint8_t conf; if((ret = util_sys_inb(base_addr+UART_LCR, &conf))) return ret; |
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| 55 | return uart_write_config(base_addr, conf & (~UART_DLAB));
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| 56 | } |
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| 57 | |||
| 58 | int uart_write_config(int base_addr, uint8_t config){ |
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| 59 | printf("WRITING CONFIG 0x%02X TO 0x%X\n", config, base_addr);
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| 60 | if(sys_outb(base_addr+UART_LCR, config)) return WRITE_ERROR; |
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| 61 | return SUCCESS;
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| 62 | } |
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| 63 | int uart_set_bits_per_character(int base_addr, uint8_t bits_per_char){ |
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| 64 | if(bits_per_char < 5 || bits_per_char > 8) return INVALID_ARG; |
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| 65 | int ret = SUCCESS;
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| 66 | bits_per_char = (bits_per_char-5)&0x3; |
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| 67 | uint8_t conf; if((ret = util_sys_inb(base_addr+UART_LCR, &conf))) return ret; |
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| 68 | conf = (conf & (~UART_BITS_PER_CHAR)) | bits_per_char; |
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| 69 | return uart_write_config(base_addr, conf);
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| 70 | } |
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| 71 | int uart_set_stop_bits(int base_addr, uint8_t stop){ |
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| 72 | if(stop != 1 && stop != 2) return INVALID_ARG; |
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| 73 | int ret = SUCCESS;
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| 74 | stop -= 1;
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| 75 | stop = (stop&1)<<2; |
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| 76 | uint8_t conf; if((ret = util_sys_inb(base_addr+UART_LCR, &conf))) return ret; |
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| 77 | conf = (conf & (~UART_STOP_BITS)) | stop; |
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| 78 | return uart_write_config(base_addr, conf);
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| 79 | } |
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| 80 | int uart_set_parity(int base_addr, uart_parity par){ |
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| 81 | int ret = SUCCESS;
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| 82 | uint8_t parity = par << 3;
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| 83 | uint8_t conf; if((ret = util_sys_inb(base_addr+UART_LCR, &conf))) return ret; |
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| 84 | conf = (conf & (~UART_PARITY)) | parity; |
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| 85 | return uart_write_config(base_addr, conf);
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| 86 | } |
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| 87 | int uart_set_bit_rate(int base_addr, float bit_rate){ printf("%s, L82\n", __func__); |
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| 88 | int ret = SUCCESS;
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| 89 | uint16_t latch = UART_BITRATE/bit_rate; |
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| 90 | uint8_t dll = latch&0xFF;
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| 91 | uint8_t dlm = (latch>>8)&0xFF; |
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| 92 | if((ret = uart_enable_divisor_latch(base_addr))) return ret; |
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| 93 | printf("dlm,dll=0x%02X%02X\n", dlm, dll);
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| 94 | if(sys_outb(base_addr+UART_DLL, dll)) return WRITE_ERROR; |
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| 95 | if(sys_outb(base_addr+UART_DLM, dlm)) return WRITE_ERROR; |
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| 96 | if((ret = util_sys_inb(base_addr+UART_DLM, &dlm))) return ret; |
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| 97 | printf("dlm=0x%02X\n", dlm);
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| 98 | printf("%s, L91\n", __func__);
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| 99 | return SUCCESS;
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| 100 | } |