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Index: git/arch/arm/Kconfig
===================================================================
--- git.orig/arch/arm/Kconfig 2006-07-04 21:48:58.000000000 +0100
+++ git/arch/arm/Kconfig 2006-07-05 09:46:49.000000000 +0100
@@ -690,7 +690,7 @@
endmenu
-if (ARCH_SA1100 || ARCH_INTEGRATOR || ARCH_OMAP)
+if (ARCH_SA1100 || ARCH_INTEGRATOR || ARCH_OMAP || ARCH_PXA)
menu "CPU Frequency scaling"
@@ -717,6 +717,12 @@
If in doubt, say Y.
+config CPU_FREQ_PXA25x
+ bool
+ select CPU_FREQ_TABLE
+ depends on CPU_FREQ && PXA25x
+ default y
+
endmenu
endif
Index: git/arch/arm/mach-pxa/Makefile
===================================================================
--- git.orig/arch/arm/mach-pxa/Makefile 2006-07-05 09:44:45.000000000 +0100
+++ git/arch/arm/mach-pxa/Makefile 2006-07-05 09:45:43.000000000 +0100
@@ -29,6 +29,9 @@
obj-$(CONFIG_LEDS) += $(led-y)
+# CPU freq support
+obj-$(CONFIG_CPU_FREQ_PXA25x) += cpu-pxa25x.o
+
# Misc features
obj-$(CONFIG_PM) += pm.o sleep.o
obj-$(CONFIG_PXA_KEYS) += pxa_keys.o
Index: git/arch/arm/mach-pxa/cpu-pxa25x.c
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ git/arch/arm/mach-pxa/cpu-pxa25x.c 2006-07-05 09:45:43.000000000 +0100
@@ -0,0 +1,353 @@
+/*
+ * linux/arch/arm/mach-pxa/cpu-pxa.c
+ *
+ * Copyright (C) 2002,2003 Intrinsyc Software
+ *
+ * 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * History:
+ * 31-Jul-2002 : Initial version [FB]
+ * 29-Jan-2003 : added PXA255 support [FB]
+ * 20-Apr-2003 : ported to v2.5 (Dustin McIntire, Sensoria Corp.)
+ * 18-Jul-2005 : updated for latest kernel (2.6.13-rc), cleanup for submission
+ * (Ian Campbell, Arcom Control Systems)
+ *
+ * Note:
+ * This driver may change the memory bus clock rate, but will not do any
+ * platform specific access timing changes... for example if you have flash
+ * memory connected to CS0, you will need to register a platform specific
+ * notifier which will adjust the memory access strobes to maintain a
+ * minimum strobe width.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/init.h>
+#include <linux/cpufreq.h>
+#include <linux/moduleparam.h>
+
+#include <asm/hardware.h>
+
+#include <asm/arch/pxa-regs.h>
+
+#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_DRIVER, "pxa25x", msg)
+
+struct pxa_freqs {
+ unsigned int khz;
+ unsigned int membus;
+ unsigned int cccr;
+ unsigned int div2;
+};
+
+/* Define the refresh period in mSec for the SDRAM and the number of rows */
+#define SDRAM_TREF 64 /* standard 64ms SDRAM */
+#define SDRAM_ROWS 8192 /* 64MB=8192 32MB=4096 */
+#define MDREFR_DRI(x) ((x*SDRAM_TREF)/(SDRAM_ROWS*32))
+
+#define CCLKCFG_TURBO 0x1
+#define CCLKCFG_FCS 0x2
+#define PXA25x_MIN_FREQ 99532
+#define PXA25x_MAX_FREQ 398131
+#define MDREFR_DB2_MASK (MDREFR_K2DB2 | MDREFR_K1DB2)
+#define MDREFR_DRI_MASK 0xFFF
+
+/* Use the run mode frequencies for performance */
+static struct pxa_freqs pxa25x_performance_freqs[] = {
+ /* CPU MEMBUS CCCR DIV2 */
+ {99532, 99532, 0x121, 1}, /* run= 99, turbo= 99, PXbus=50, SDRAM=50 */
+ {132710, 132710, 0x123, 1}, /* run=133, turbo=133, PXbus=66, SDRAM=66 */
+ {199065, 99532, 0x141, 0}, /* run=199, turbo=199, PXbus=99, SDRAM=99 */
+ {265421, 132710, 0x143, 1}, /* run=265, turbo=265, PXbus=133, SDRAM=66 */
+ {331776, 165888, 0x145, 1}, /* run=331, turbo=331, PXbus=166, SDRAM=83 */
+ {398131, 99532, 0x161, 0}, /* run=398, turbo=398, PXbus=196, SDRAM=99 */
+};
+
+static struct cpufreq_frequency_table pxa25x_performance_freq_table[ARRAY_SIZE(pxa25x_performance_freqs)+1];
+
+/* Use the turbo mode frequencies for powersave */
+static struct pxa_freqs pxa25x_powersave_freqs[] = {
+ /* CPU MEMBUS CCCR DIV2 */
+ {99532, 99532, 0x121, 1}, /* run=99, turbo= 99, PXbus=50, SDRAM=50 */
+ {199065, 99532, 0x221, 0}, /* run=99, turbo=199, PXbus=50, SDRAM=99 */
+ {298598, 99532, 0x321, 0}, /* run=99, turbo=287, PXbus=50, SDRAM=99 */
+ {398131, 99532, 0x241, 0}, /* run=199, turbo=398, PXbus=99, SDRAM=99 */
+};
+
+static struct cpufreq_frequency_table pxa25x_powersave_freq_table[ARRAY_SIZE(pxa25x_powersave_freqs)+1];
+
+extern unsigned get_clk_frequency_khz(int info);
+
+static unsigned int max_frequency = PXA25x_MAX_FREQ;
+static int performance = 0;
+
+/*
+ * This option can be used if you have one of the 200MHz PXA25x parts by adding
+ * cpu_pxa25x.max_frequency=199065 to the kernel command line
+ */
+module_param(max_frequency, int, 0);
+MODULE_PARM_DESC(max_frequency, "Set the maximum cpu frequency");
+
+module_param(performance, int, 0);
+MODULE_PARM_DESC(performance, "Use performance instead of powersave frequency tables");
+
+static void pxa_select_freq_table(struct cpufreq_policy *policy,
+ struct pxa_freqs ** settings,
+ struct cpufreq_frequency_table **table)
+{
+ cpufreq_frequency_table_put_attr(policy->cpu);
+
+ if (performance) {
+ dprintk("selecting performance tables\n");
+ cpufreq_frequency_table_get_attr(pxa25x_performance_freq_table, policy->cpu);
+ if (settings)
+ *settings = pxa25x_performance_freqs;
+ if (table)
+ *table = pxa25x_performance_freq_table;
+ } else {
+ dprintk("selecting powersave tables\n");
+ cpufreq_frequency_table_get_attr(pxa25x_powersave_freq_table, policy->cpu);
+ if (settings)
+ *settings = pxa25x_powersave_freqs;
+ if (table)
+ *table = pxa25x_powersave_freq_table;
+ }
+}
+
+/* find a valid frequency point */
+static int pxa_verify_policy(struct cpufreq_policy *policy)
+{
+ int ret;
+ struct cpufreq_frequency_table *pxa_freqs_table;
+
+ pxa_select_freq_table(policy, NULL, &pxa_freqs_table);
+
+ ret = cpufreq_frequency_table_verify(policy, pxa_freqs_table);
+
+ dprintk("verified CPU policy: %dKhz min to %dKhz max\n",
+ policy->min, policy->max);
+
+ return ret;
+}
+
+static int pxa_set_target(struct cpufreq_policy *policy,
+ unsigned int target_freq, unsigned int relation)
+{
+ int idx;
+ struct cpufreq_freqs freqs;
+ struct pxa_freqs *pxa_freq_settings;
+ struct cpufreq_frequency_table *pxa_freqs_table;
+ unsigned long flags;
+ unsigned int unused;
+ unsigned int preset_mdrefr, postset_mdrefr;
+ void *ramstart;
+
+ /* Get the current policy */
+ pxa_select_freq_table(policy, &pxa_freq_settings, &pxa_freqs_table);
+
+ /* Lookup the next frequency */
+ if (cpufreq_frequency_table_target(policy, pxa_freqs_table,
+ target_freq, relation, &idx))
+ return -EINVAL;
+
+ freqs.old = get_clk_frequency_khz(0);
+ freqs.new = pxa_freq_settings[idx].khz;
+ freqs.cpu = policy->cpu;
+
+ if (freqs.new == freqs.old && pxa_freq_settings[idx].cccr == CCCR)
+ return 0;
+
+ dprintk("changing CPU frequency to %d.%03d Mhz (SDRAM %d Mhz, CCCR %#04x)\n",
+ freqs.new / 1000, freqs.new % 1000,
+ (pxa_freq_settings[idx].div2) ?
+ (pxa_freq_settings[idx].membus / 2000) :
+ (pxa_freq_settings[idx].membus / 1000),
+ pxa_freq_settings[idx].cccr);
+
+ ramstart = phys_to_virt(0xa0000000);
+
+ /*
+ * Tell everyone what we're about to do...
+ * you should add a notify client with any platform specific
+ * Vcc changing capability
+ */
+ cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
+
+ /* Calculate the next MDREFR. If we're slowing down the SDRAM clock
+ * we need to preset the smaller DRI before the change. If we're speeding
+ * up we need to set the larger DRI value after the change.
+ */
+ preset_mdrefr = postset_mdrefr = MDREFR;
+ if ((MDREFR & MDREFR_DRI_MASK) > MDREFR_DRI(pxa_freq_settings[idx].membus)) {
+ preset_mdrefr = (preset_mdrefr & ~MDREFR_DRI_MASK) |
+ MDREFR_DRI(pxa_freq_settings[idx].membus);
+ }
+ postset_mdrefr = (postset_mdrefr & ~MDREFR_DRI_MASK) |
+ MDREFR_DRI(pxa_freq_settings[idx].membus);
+
+ /* If we're dividing the memory clock by two for the SDRAM clock, this
+ * must be set prior to the change. Clearing the divide must be done
+ * after the change.
+ */
+ if (pxa_freq_settings[idx].div2) {
+ preset_mdrefr |= MDREFR_DB2_MASK;
+ postset_mdrefr |= MDREFR_DB2_MASK;
+ } else {
+ postset_mdrefr &= ~MDREFR_DB2_MASK;
+ }
+
+ local_irq_save(flags);
+
+ /* Set new the CCCR */
+ CCCR = pxa_freq_settings[idx].cccr;
+
+ __asm__ __volatile__(" \
+ ldr r4, [%1] ; /* load MDREFR */ \
+ b 2f ; \
+ .align 5 ; \
+1: \
+ str %4, [%1] ; /* preset the MDREFR */ \
+ mcr p14, 0, %2, c6, c0, 0 ; /* set CCLKCFG[FCS] */ \
+ str %5, [%1] ; /* postset the MDREFR */ \
+ \
+ b 3f ; \
+2: b 1b ; \
+3: nop ; \
+ "
+ : "=&r"(unused)
+ : "r"(&MDREFR), "r"(CCLKCFG_TURBO | CCLKCFG_FCS),
+ "r"(ramstart), "r"(preset_mdrefr),
+ "r"(postset_mdrefr)
+ : "r4", "r5");
+ local_irq_restore(flags);
+
+ /*
+ * Tell everyone what we've just done...
+ * you should add a notify client with any platform specific
+ * SDRAM refresh timer adjustments
+ */
+ cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+
+ return 0;
+}
+
+static unsigned int pxa_cpufreq_get(unsigned int cpu)
+{
+ return get_clk_frequency_khz(0);
+}
+
+static int pxa_cpufreq_init(struct cpufreq_policy *policy)
+{
+ int i;
+
+ if (policy->cpu != 0)
+ return -ENODEV;
+
+ /* set default policy and cpuinfo */
+ policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
+ policy->cpuinfo.max_freq = max_frequency;
+ policy->cpuinfo.min_freq = PXA25x_MIN_FREQ;
+ policy->cpuinfo.transition_latency = 1000000; /* FIXME: 1 ms, assumed */
+ policy->cur = get_clk_frequency_khz(0); /* current freq */
+ policy->min = policy->max = policy->cur;
+ policy->min = pxa25x_powersave_freqs[0].khz;
+ policy->max = pxa25x_powersave_freqs[sizeof(pxa25x_powersave_freqs)/sizeof(*pxa25x_powersave_freqs)-1].khz;
+
+ /* Generate the run cpufreq_frequency_table struct */
+ for (i = 0; i < ARRAY_SIZE(pxa25x_performance_freqs); i++) {
+ pxa25x_performance_freq_table[i].frequency = pxa25x_performance_freqs[i].khz;
+ pxa25x_performance_freq_table[i].index = i;
+ }
+ pxa25x_performance_freq_table[i].frequency = CPUFREQ_TABLE_END;
+
+ /* Generate the turbo cpufreq_frequency_table struct */
+ for (i = 0; i < ARRAY_SIZE(pxa25x_powersave_freqs); i++) {
+ pxa25x_powersave_freq_table[i].frequency = pxa25x_powersave_freqs[i].khz;
+ pxa25x_powersave_freq_table[i].index = i;
+ }
+ pxa25x_powersave_freq_table[i].frequency = CPUFREQ_TABLE_END;
+
+ /* calls cpufreq_frequency_table_get_attr */
+ pxa_select_freq_table(policy, NULL, NULL);
+
+ printk(KERN_INFO "pxa25x: CPU frequency change support initialized (%s tables)\n",
+ performance ? "performance" : "powersave");
+
+ return 0;
+}
+
+static ssize_t show_pxa25x_freq_model_attr(struct cpufreq_policy * policy, char *buf)
+{
+ return sprintf (buf, "%s\n", performance ? "performance" : "powersave");
+}
+
+static ssize_t store_pxa25x_freq_model_attr(struct cpufreq_policy * policy, const char *buf, size_t count)
+{
+ unsigned int ret;
+ char str[16];
+
+ ret = sscanf(buf, "%15s", str);
+ if (ret != 1)
+ return -EINVAL;
+
+ if (strnicmp(str,"performance",16)==0)
+ performance = 1;
+ else if (strnicmp(str,"powersave",16)==0)
+ performance = 0;
+ else
+ return -EINVAL;
+
+ ret = cpufreq_update_policy(policy->cpu);
+
+ return ret ? ret : count;
+}
+
+struct freq_attr pxa25x_freq_model_attr = {
+ .attr = { .name = "pxa25x_freq_model", .mode = 0644, .owner=THIS_MODULE },
+ .show = show_pxa25x_freq_model_attr,
+ .store = store_pxa25x_freq_model_attr,
+};
+
+static struct freq_attr* pxa_cpufreq_attr[] = {
+ &cpufreq_freq_attr_scaling_available_freqs,
+ &pxa25x_freq_model_attr,
+ NULL,
+};
+
+static struct cpufreq_driver pxa_cpufreq_driver = {
+ .verify = pxa_verify_policy,
+ .target = pxa_set_target,
+ .init = pxa_cpufreq_init,
+ .get = pxa_cpufreq_get,
+ .name = "pxa25x",
+ .attr = pxa_cpufreq_attr,
+};
+
+static int __init pxa_cpu_init(void)
+{
+ return cpufreq_register_driver(&pxa_cpufreq_driver);
+}
+
+static void __exit pxa_cpu_exit(void)
+{
+ cpufreq_unregister_driver(&pxa_cpufreq_driver);
+}
+
+MODULE_AUTHOR("Intrinsyc Software Inc.");
+MODULE_DESCRIPTION("CPU frequency changing driver for the PXA architecture");
+MODULE_LICENSE("GPL");
+module_init(pxa_cpu_init);
+module_exit(pxa_cpu_exit);
|