| 1 | /* |
| 2 | * QEMU MC146818 RTC emulation |
| 3 | * |
| 4 | * Copyright (c) 2003-2004 Fabrice Bellard |
| 5 | * |
| 6 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 7 | * of this software and associated documentation files (the "Software"), to deal |
| 8 | * in the Software without restriction, including without limitation the rights |
| 9 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| 10 | * copies of the Software, and to permit persons to whom the Software is |
| 11 | * furnished to do so, subject to the following conditions: |
| 12 | * |
| 13 | * The above copyright notice and this permission notice shall be included in |
| 14 | * all copies or substantial portions of the Software. |
| 15 | * |
| 16 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 17 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 18 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| 19 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 20 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 21 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| 22 | * THE SOFTWARE. |
| 23 | */ |
| 24 | |
| 25 | #ifndef HW_RTC_MC146818RTC_REGS_H |
| 26 | #define HW_RTC_MC146818RTC_REGS_H |
| 27 | |
| 28 | #include "qemu/timer.h" |
| 29 | #include "qemu/host-utils.h" |
| 30 | |
| 31 | #define RTC_SECONDS 0 |
| 32 | #define RTC_SECONDS_ALARM 1 |
| 33 | #define RTC_MINUTES 2 |
| 34 | #define RTC_MINUTES_ALARM 3 |
| 35 | #define RTC_HOURS 4 |
| 36 | #define RTC_HOURS_ALARM 5 |
| 37 | #define RTC_ALARM_DONT_CARE 0xC0 |
| 38 | |
| 39 | #define RTC_DAY_OF_WEEK 6 |
| 40 | #define RTC_DAY_OF_MONTH 7 |
| 41 | #define RTC_MONTH 8 |
| 42 | #define RTC_YEAR 9 |
| 43 | |
| 44 | #define RTC_REG_A 10 |
| 45 | #define RTC_REG_B 11 |
| 46 | #define RTC_REG_C 12 |
| 47 | #define RTC_REG_D 13 |
| 48 | |
| 49 | /* PC cmos mappings */ |
| 50 | #define RTC_CENTURY 0x32 |
| 51 | #define RTC_IBM_PS2_CENTURY_BYTE 0x37 |
| 52 | |
| 53 | #define REG_A_UIP 0x80 |
| 54 | |
| 55 | #define REG_B_SET 0x80 |
| 56 | #define REG_B_PIE 0x40 |
| 57 | #define REG_B_AIE 0x20 |
| 58 | #define REG_B_UIE 0x10 |
| 59 | #define REG_B_SQWE 0x08 |
| 60 | #define REG_B_DM 0x04 |
| 61 | #define REG_B_24H 0x02 |
| 62 | |
| 63 | #define REG_C_UF 0x10 |
| 64 | #define REG_C_IRQF 0x80 |
| 65 | #define REG_C_PF 0x40 |
| 66 | #define REG_C_AF 0x20 |
| 67 | #define REG_C_MASK 0x70 |
| 68 | |
| 69 | static inline uint32_t periodic_period_to_clock(int period_code) |
| 70 | { |
| 71 | if (!period_code) { |
| 72 | return 0; |
| 73 | } |
| 74 | |
| 75 | if (period_code <= 2) { |
| 76 | period_code += 7; |
| 77 | } |
| 78 | /* period in 32 Khz cycles */ |
| 79 | return 1 << (period_code - 1); |
| 80 | } |
| 81 | |
| 82 | #define RTC_CLOCK_RATE 32768 |
| 83 | |
| 84 | static inline int64_t periodic_clock_to_ns(int64_t clocks) |
| 85 | { |
| 86 | return muldiv64(clocks, NANOSECONDS_PER_SECOND, RTC_CLOCK_RATE); |
| 87 | } |
| 88 | |
| 89 | #endif |