projects / mirror_ubuntu-kernels.git / blame
| Commit | Line | Data |
|---|---|---|
| b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
| 1da177e4 LT |
2 | /* |
| 3 | * linux/arch/m68k/hp300/time.c | |
| 4 | * | |
| 5 | * Copyright (C) 1998 Philip Blundell <philb@gnu.org> | |
| 6 | * | |
| 7 | * This file contains the HP300-specific time handling code. | |
| 8 | */ | |
| 9 | ||
| 10 | #include <asm/ptrace.h> | |
| 11 | #include <linux/types.h> | |
| 12 | #include <linux/init.h> | |
| 13 | #include <linux/sched.h> | |
| 14 | #include <linux/kernel_stat.h> | |
| 15 | #include <linux/interrupt.h> | |
| 16 | #include <asm/machdep.h> | |
| 17 | #include <asm/irq.h> | |
| 18 | #include <asm/io.h> | |
| 1da177e4 LT |
19 | #include <asm/traps.h> |
| 20 | #include <asm/blinken.h> | |
| 1da177e4 LT |
21 | |
| 22 | /* Clock hardware definitions */ | |
| 23 | ||
| 24 | #define CLOCKBASE 0xf05f8000 | |
| 25 | ||
| 26 | #define CLKCR1 0x1 | |
| 27 | #define CLKCR2 0x3 | |
| 28 | #define CLKCR3 CLKCR1 | |
| 29 | #define CLKSR CLKCR2 | |
| 30 | #define CLKMSB1 0x5 | |
| 31 | #define CLKMSB2 0x9 | |
| 32 | #define CLKMSB3 0xD | |
| 33 | ||
| 34 | /* This is for machines which generate the exact clock. */ | |
| 35 | #define USECS_PER_JIFFY (1000000/HZ) | |
| 36 | ||
| 37 | #define INTVAL ((10000 / 4) - 1) | |
| 38 | ||
| 2850bc27 | 39 | static irqreturn_t hp300_tick(int irq, void *dev_id) |
| 1da177e4 LT |
40 | { |
| 41 | unsigned long tmp; | |
| 40220c1a | 42 | irq_handler_t vector = dev_id; |
| 1da177e4 LT |
43 | in_8(CLOCKBASE + CLKSR); |
| 44 | asm volatile ("movpw %1@(5),%0" : "=d" (tmp) : "a" (CLOCKBASE)); | |
| 45 | /* Turn off the network and SCSI leds */ | |
| 46 | blinken_leds(0, 0xe0); | |
| 2850bc27 | 47 | return vector(irq, NULL); |
| 1da177e4 LT |
48 | } |
| 49 | ||
| c8d5ba18 | 50 | u32 hp300_gettimeoffset(void) |
| 1da177e4 LT |
51 | { |
| 52 | /* Read current timer 1 value */ | |
| 53 | unsigned char lsb, msb1, msb2; | |
| 54 | unsigned short ticks; | |
| 55 | ||
| 56 | msb1 = in_8(CLOCKBASE + 5); | |
| 57 | lsb = in_8(CLOCKBASE + 7); | |
| 58 | msb2 = in_8(CLOCKBASE + 5); | |
| 59 | if (msb1 != msb2) | |
| 60 | /* A carry happened while we were reading. Read it again */ | |
| 61 | lsb = in_8(CLOCKBASE + 7); | |
| 62 | ticks = INTVAL - ((msb2 << 8) | lsb); | |
| c8d5ba18 | 63 | return ((USECS_PER_JIFFY * ticks) / INTVAL) * 1000; |
| 1da177e4 LT |
64 | } |
| 65 | ||
| 40220c1a | 66 | void __init hp300_sched_init(irq_handler_t vector) |
| 1da177e4 LT |
67 | { |
| 68 | out_8(CLOCKBASE + CLKCR2, 0x1); /* select CR1 */ | |
| 69 | out_8(CLOCKBASE + CLKCR1, 0x1); /* reset */ | |
| 70 | ||
| 71 | asm volatile(" movpw %0,%1@(5)" : : "d" (INTVAL), "a" (CLOCKBASE)); | |
| 72 | ||
| 5a239453 | 73 | if (request_irq(IRQ_AUTO_6, hp300_tick, 0, "timer tick", vector)) |
| 8bd3968b | 74 | pr_err("Couldn't register timer interrupt\n"); |
| 1da177e4 LT |
75 | |
| 76 | out_8(CLOCKBASE + CLKCR2, 0x1); /* select CR1 */ | |
| 77 | out_8(CLOCKBASE + CLKCR1, 0x40); /* enable irq */ | |
| 78 | } |