mirror of
git://projects.qi-hardware.com/openwrt-xburst.git
synced 2024-11-06 18:16:15 +02:00
d4e976a36f
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@10455 3c298f89-4303-0410-b956-a3cf2f4a3e73
119 lines
3.2 KiB
C
119 lines
3.2 KiB
C
/*
|
|
<:copyright-gpl
|
|
Copyright 2004 Broadcom Corp. All Rights Reserved.
|
|
|
|
This program is free software; you can distribute it and/or modify it
|
|
under the terms of the GNU General Public License (Version 2) as
|
|
published by the Free Software Foundation.
|
|
|
|
This program is distributed in the hope it will be useful, but WITHOUT
|
|
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
|
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
|
for more details.
|
|
|
|
You should have received a copy of the GNU General Public License along
|
|
with this program; if not, write to the Free Software Foundation, Inc.,
|
|
59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
|
|
:>
|
|
*/
|
|
/*
|
|
* Setup time for Broadcom 963xx MIPS boards
|
|
*/
|
|
|
|
#include <linux/autoconf.h>
|
|
#include <linux/init.h>
|
|
#include <linux/kernel_stat.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/module.h>
|
|
#include <linux/time.h>
|
|
#include <linux/timex.h>
|
|
|
|
#include <asm/mipsregs.h>
|
|
#include <asm/ptrace.h>
|
|
#include <asm/div64.h>
|
|
#include <asm/time.h>
|
|
|
|
#include <6348_map_part.h>
|
|
#include <6348_intr.h>
|
|
#include <bcm_map_part.h>
|
|
#include <bcm_intr.h>
|
|
|
|
static unsigned long r4k_offset; /* Amount to increment compare reg each time */
|
|
static unsigned long r4k_cur; /* What counter should be at next timer irq */
|
|
|
|
/* *********************************************************************
|
|
* calculateCpuSpeed()
|
|
* Calculate the BCM6348 CPU speed by reading the PLL strap register
|
|
* and applying the following formula:
|
|
* cpu_clk = (.25 * 64MHz freq) * (N1 + 1) * (N2 + 2) / (M1_CPU + 1)
|
|
* Input parameters:
|
|
* none
|
|
* Return value:
|
|
* none
|
|
********************************************************************* */
|
|
|
|
static inline unsigned long __init calculateCpuSpeed(void)
|
|
{
|
|
u32 pllStrap = PERF->PllStrap;
|
|
int n1 = (pllStrap & PLL_N1_MASK) >> PLL_N1_SHFT;
|
|
int n2 = (pllStrap & PLL_N2_MASK) >> PLL_N2_SHFT;
|
|
int m1cpu = (pllStrap & PLL_M1_CPU_MASK) >> PLL_M1_CPU_SHFT;
|
|
|
|
return (16 * (n1 + 1) * (n2 + 2) / (m1cpu + 1)) * 1000000;
|
|
}
|
|
|
|
|
|
static inline unsigned long __init cal_r4koff(void)
|
|
{
|
|
mips_hpt_frequency = calculateCpuSpeed() / 2;
|
|
return (mips_hpt_frequency / HZ);
|
|
}
|
|
|
|
|
|
/*
|
|
* There are a lot of conceptually broken versions of the MIPS timer interrupt
|
|
* handler floating around. This one is rather different, but the algorithm
|
|
* is provably more robust.
|
|
*/
|
|
#if 0
|
|
irqreturn_t brcm_timer_interrupt(struct pt_regs *regs)
|
|
{
|
|
int irq = MIPS_TIMER_INT;
|
|
|
|
irq_enter();
|
|
kstat_this_cpu.irqs[irq]++;
|
|
|
|
timer_interrupt(irq, regs);
|
|
irq_exit();
|
|
return IRQ_HANDLED;
|
|
}
|
|
#endif
|
|
|
|
void __init plat_time_init(void)
|
|
{
|
|
unsigned int est_freq, flags;
|
|
local_irq_save(flags);
|
|
|
|
printk("calculating r4koff... ");
|
|
r4k_offset = cal_r4koff();
|
|
printk("%08lx(%d)\n", r4k_offset, (int)r4k_offset);
|
|
|
|
est_freq = 2 * r4k_offset * HZ;
|
|
est_freq += 5000; /* round */
|
|
est_freq -= est_freq % 10000;
|
|
printk("CPU frequency %d.%02d MHz\n", est_freq / 1000000,
|
|
(est_freq % 1000000) * 100 / 1000000);
|
|
local_irq_restore(flags);
|
|
}
|
|
|
|
#if 0
|
|
void __init plat_timer_setup(struct irqaction *irq)
|
|
{
|
|
r4k_cur = (read_c0_count() + r4k_offset);
|
|
write_c0_compare(r4k_cur);
|
|
set_c0_status(IE_IRQ5);
|
|
}
|
|
#endif
|