kernel-fxtec-pro1x/arch/blackfin/mach-bf548/cpu.c
Roy Huang 24a07a1241 Blackfin arch: initial supporting for BF548-EZKIT
The ADSP-BF54x was specifically designed to meet the needs of convergent multimedia
applications where system performance and cost are essential ingredients. The
integration of multimedia, human interface, and connectivity peripherals combined
with increased system bandwidth and on-chip memory provides customers a platform to
design the most demanding applications.

Since now, ADSP-BF54x will be supported in the Linux kernel and bunch of related drivers
such as USB OTG, ATAPI, NAND flash controller, LCD framebuffer, sound, touch screen will
be submitted later.

Please enjoy the show.

Signed-off-by: Roy Huang <roy.huang@analog.com>
Signed-off-by: Bryan Wu <bryan.wu@analog.com>
2007-07-12 22:41:45 +08:00

159 lines
4.3 KiB
C

/*
* File: arch/blackfin/mach-bf548/cpu.c
* Based on:
* Author:
*
* Created:
* Description: clock scaling for the bf54x
*
* Modified:
* Copyright 2004-2007 Analog Devices Inc.
*
* Bugs: Enter bugs at http://blackfin.uclinux.org/
*
* 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.
*
* This program is distributed in the hope that 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, see the file COPYING, or write
* to the Free Software Foundation, Inc.,
* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/cpufreq.h>
#include <asm/dpmc.h>
#include <linux/fs.h>
#include <asm/bfin-global.h>
/* CONFIG_CLKIN_HZ=25000000 */
#define VCO5 (CONFIG_CLKIN_HZ*45)
#define VCO4 (CONFIG_CLKIN_HZ*36)
#define VCO3 (CONFIG_CLKIN_HZ*27)
#define VCO2 (CONFIG_CLKIN_HZ*18)
#define VCO1 (CONFIG_CLKIN_HZ*9)
#define VCO(x) VCO##x
#define MFREQ(x) {VCO(x),VCO(x)/4},{VCO(x),VCO(x)/2},{VCO(x),VCO(x)}
/* frequency */
static struct cpufreq_frequency_table bf548_freq_table[] = {
MFREQ(1),
MFREQ(3),
{VCO4, VCO4 / 2}, {VCO4, VCO4},
MFREQ(5),
{0, CPUFREQ_TABLE_END},
};
/*
* dpmc_fops->ioctl()
* static int dpmc_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
*/
static int bf548_getfreq(unsigned int cpu)
{
unsigned long cclk_mhz;
/* The driver only support single cpu */
if (cpu == 0)
dpmc_fops.ioctl(NULL, NULL, IOCTL_GET_CORECLOCK, &cclk_mhz);
else
cclk_mhz = -1;
return cclk_mhz;
}
static int bf548_target(struct cpufreq_policy *policy,
unsigned int target_freq, unsigned int relation)
{
unsigned long cclk_mhz;
unsigned long vco_mhz;
unsigned long flags;
unsigned int index;
struct cpufreq_freqs freqs;
if (cpufreq_frequency_table_target(policy, bf548_freq_table, target_freq, relation, &index))
return -EINVAL;
cclk_mhz = bf548_freq_table[index].frequency;
vco_mhz = bf548_freq_table[index].index;
dpmc_fops.ioctl(NULL, NULL, IOCTL_CHANGE_FREQUENCY, &vco_mhz);
freqs.old = bf548_getfreq(0);
freqs.new = cclk_mhz;
freqs.cpu = 0;
pr_debug("cclk begin change to cclk %d,vco=%d,index=%d,target=%d,oldfreq=%d\n",
cclk_mhz, vco_mhz, index, target_freq, freqs.old);
cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
local_irq_save(flags);
dpmc_fops.ioctl(NULL, NULL, IOCTL_SET_CCLK, &cclk_mhz);
local_irq_restore(flags);
cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
vco_mhz = get_vco();
cclk_mhz = get_cclk();
return 0;
}
/* make sure that only the "userspace" governor is run -- anything else wouldn't make sense on
* this platform, anyway.
*/
static int bf548_verify_speed(struct cpufreq_policy *policy)
{
return cpufreq_frequency_table_verify(policy, &bf548_freq_table);
}
static int __init __bf548_cpu_init(struct cpufreq_policy *policy)
{
if (policy->cpu != 0)
return -EINVAL;
policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
policy->cpuinfo.transition_latency = CPUFREQ_ETERNAL;
/*Now ,only support one cpu */
policy->cur = bf548_getfreq(0);
cpufreq_frequency_table_get_attr(bf548_freq_table, policy->cpu);
return cpufreq_frequency_table_cpuinfo(policy, bf548_freq_table);
}
static struct freq_attr *bf548_freq_attr[] = {
&cpufreq_freq_attr_scaling_available_freqs,
NULL,
};
static struct cpufreq_driver bf548_driver = {
.verify = bf548_verify_speed,
.target = bf548_target,
.get = bf548_getfreq,
.init = __bf548_cpu_init,
.name = "bf548",
.owner = THIS_MODULE,
.attr = bf548_freq_attr,
};
static int __init bf548_cpu_init(void)
{
return cpufreq_register_driver(&bf548_driver);
}
static void __exit bf548_cpu_exit(void)
{
cpufreq_unregister_driver(&bf548_driver);
}
MODULE_AUTHOR("Mickael Kang");
MODULE_DESCRIPTION("cpufreq driver for BF548 CPU");
MODULE_LICENSE("GPL");
module_init(bf548_cpu_init);
module_exit(bf548_cpu_exit);