diff options
Diffstat (limited to 'arch/mips/philips/pnx8550/common/time.c')
| -rw-r--r-- | arch/mips/philips/pnx8550/common/time.c | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/arch/mips/philips/pnx8550/common/time.c b/arch/mips/philips/pnx8550/common/time.c new file mode 100644 index 0000000..70664ea --- /dev/null +++ b/arch/mips/philips/pnx8550/common/time.c @@ -0,0 +1,105 @@ +/* + * Copyright 2001, 2002, 2003 MontaVista Software Inc. + * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net + * + * Common time service routines for MIPS machines. See + * Documents/MIPS/README.txt. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/sched.h> +#include <linux/param.h> +#include <linux/time.h> +#include <linux/timer.h> +#include <linux/smp.h> +#include <linux/kernel_stat.h> +#include <linux/spinlock.h> +#include <linux/interrupt.h> +#include <linux/module.h> + +#include <asm/bootinfo.h> +#include <asm/cpu.h> +#include <asm/time.h> +#include <asm/hardirq.h> +#include <asm/div64.h> +#include <asm/debug.h> + +#include <int.h> +#include <cm.h> + +extern unsigned int mips_hpt_frequency; + +/* + * pnx8550_time_init() - it does the following things: + * + * 1) board_time_init() - + * a) (optional) set up RTC routines, + * b) (optional) calibrate and set the mips_hpt_frequency + * (only needed if you intended to use fixed_rate_gettimeoffset + * or use cpu counter as timer interrupt source) + */ + +void pnx8550_time_init(void) +{ + unsigned int n; + unsigned int m; + unsigned int p; + unsigned int pow2p; + + /* PLL0 sets MIPS clock (PLL1 <=> TM1, PLL6 <=> TM2, PLL5 <=> mem) */ + /* (but only if CLK_MIPS_CTL select value [bits 3:1] is 1: FIXME) */ + + n = (PNX8550_CM_PLL0_CTL & PNX8550_CM_PLL_N_MASK) >> 16; + m = (PNX8550_CM_PLL0_CTL & PNX8550_CM_PLL_M_MASK) >> 8; + p = (PNX8550_CM_PLL0_CTL & PNX8550_CM_PLL_P_MASK) >> 2; + pow2p = (1 << p); + + db_assert(m != 0 && pow2p != 0); + + /* + * Compute the frequency as in the PNX8550 User Manual 1.0, p.186 + * (a.k.a. 8-10). Divide by HZ for a timer offset that results in + * HZ timer interrupts per second. + */ + mips_hpt_frequency = 27UL * ((1000000UL * n)/(m * pow2p)); +} + +/* + * pnx8550_timer_setup() - it does the following things: + * + * 5) board_timer_setup() - + * a) (optional) over-write any choices made above by time_init(). + * b) machine specific code should setup the timer irqaction. + * c) enable the timer interrupt + */ + +void __init pnx8550_timer_setup(struct irqaction *irq) +{ + int configPR; + + setup_irq(PNX8550_INT_TIMER1, irq); + + /* Start timer1 */ + configPR = read_c0_config7(); + configPR &= ~0x00000008; + write_c0_config7(configPR); + + /* Timer 2 stop */ + configPR = read_c0_config7(); + configPR |= 0x00000010; + write_c0_config7(configPR); + + write_c0_count2(0); + write_c0_compare2(0xffffffff); + + /* Timer 3 stop */ + configPR = read_c0_config7(); + configPR |= 0x00000020; + write_c0_config7(configPR); +} |