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authorLinus Torvalds <torvalds@woody.linux-foundation.org>2008-02-08 10:01:28 -0800
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2008-02-08 10:01:28 -0800
commit0cf975e16927fd70f34cee20d3856246c13bb4c8 (patch)
treebb955d50f28e5d98c198701798c8341d9763299a /arch/cris/arch-v32/mach-a3/cpufreq.c
parent03054de1e0b90b33e9974107d84dabd2509f5898 (diff)
parentbc10ac3f2fe44e65f787d6197fd5d17304bf7d83 (diff)
Merge branch 'cris' of git://www.jni.nu/cris
* 'cris' of git://www.jni.nu/cris: (158 commits) CRIS v32: Remove hwregs/timer_defs.h, it is now architecture specific. CRIS v32: Change drivers/i2c.c locking. CRIS v32: Rewrite ARTPEC-3 gpio driver to avoid volatiles and general cleanup. CRIS: Add new timerfd syscall entries. MAINTAINERS: Add my information for the CRIS port. CRIS v32: Correct spelling of bandwidth in function name. CRIS v32: Clean up nandflash.c for ARTPEC-3 and ETRAX FS. CRIS v10: Cleanup of drivers/gpio.c CRIS v10: drivers/net/cris/eth_v10.c rename LED defines to CRIS_LED to avoid name clash. CRIS: Make io_pwm_set_period members unsigned in etraxgpio.h CRIS: Move ETRAX_AXISFLASHMAP to common Kconfig file. CRIS: Drop regs parameter from call to profile_tick in kernel/time.c CRIS v32: Fix minor formatting issue in mach-a3/io.c CRIS v32: Initialize GIO even if we're rambooting in kernel/head.S CRIS v32: Remove kernel/arbiter.c, it now exists in machine dependent directory. CRIS v32: Minor changes to avoid errors in asm-cris/arch-v32/hwregs/reg_rdwr.h CRIS v32: arch-v32/hwregs/intr_vect_defs.h moved to machine dependent directory. CRIS v32: Correct offset for TASK_pid in asm-cris/arch-v32/offset.h CRIS v32: Move register map header to machine dependent directory. CRIS v32: Let compiler know that memory is clobbered after a break op. ...
Diffstat (limited to 'arch/cris/arch-v32/mach-a3/cpufreq.c')
-rw-r--r--arch/cris/arch-v32/mach-a3/cpufreq.c153
1 files changed, 153 insertions, 0 deletions
diff --git a/arch/cris/arch-v32/mach-a3/cpufreq.c b/arch/cris/arch-v32/mach-a3/cpufreq.c
new file mode 100644
index 00000000000..8e5a3cab8ad
--- /dev/null
+++ b/arch/cris/arch-v32/mach-a3/cpufreq.c
@@ -0,0 +1,153 @@
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/cpufreq.h>
+#include <hwregs/reg_map.h>
+#include <hwregs/reg_rdwr.h>
+#include <hwregs/clkgen_defs.h>
+#include <hwregs/ddr2_defs.h>
+
+static int
+cris_sdram_freq_notifier(struct notifier_block *nb, unsigned long val,
+ void *data);
+
+static struct notifier_block cris_sdram_freq_notifier_block = {
+ .notifier_call = cris_sdram_freq_notifier
+};
+
+static struct cpufreq_frequency_table cris_freq_table[] = {
+ {0x01, 6000},
+ {0x02, 200000},
+ {0, CPUFREQ_TABLE_END},
+};
+
+static unsigned int cris_freq_get_cpu_frequency(unsigned int cpu)
+{
+ reg_clkgen_rw_clk_ctrl clk_ctrl;
+ clk_ctrl = REG_RD(clkgen, regi_clkgen, rw_clk_ctrl);
+ return clk_ctrl.pll ? 200000 : 6000;
+}
+
+static void cris_freq_set_cpu_state(unsigned int state)
+{
+ int i = 0;
+ struct cpufreq_freqs freqs;
+ reg_clkgen_rw_clk_ctrl clk_ctrl;
+ clk_ctrl = REG_RD(clkgen, regi_clkgen, rw_clk_ctrl);
+
+#ifdef CONFIG_SMP
+ for_each_present_cpu(i)
+#endif
+ {
+ freqs.old = cris_freq_get_cpu_frequency(i);
+ freqs.new = cris_freq_table[state].frequency;
+ freqs.cpu = i;
+ }
+
+ cpufreq_notify_transition(&freqs, CPUFREQ_PRECHANGE);
+
+ local_irq_disable();
+
+ /* Even though we may be SMP they will share the same clock
+ * so all settings are made on CPU0. */
+ if (cris_freq_table[state].frequency == 200000)
+ clk_ctrl.pll = 1;
+ else
+ clk_ctrl.pll = 0;
+ REG_WR(clkgen, regi_clkgen, rw_clk_ctrl, clk_ctrl);
+
+ local_irq_enable();
+
+ cpufreq_notify_transition(&freqs, CPUFREQ_POSTCHANGE);
+};
+
+static int cris_freq_verify(struct cpufreq_policy *policy)
+{
+ return cpufreq_frequency_table_verify(policy, &cris_freq_table[0]);
+}
+
+static int cris_freq_target(struct cpufreq_policy *policy,
+ unsigned int target_freq,
+ unsigned int relation)
+{
+ unsigned int newstate = 0;
+
+ if (cpufreq_frequency_table_target(policy, cris_freq_table,
+ target_freq, relation, &newstate))
+ return -EINVAL;
+
+ cris_freq_set_cpu_state(newstate);
+
+ return 0;
+}
+
+static int cris_freq_cpu_init(struct cpufreq_policy *policy)
+{
+ int result;
+
+ /* cpuinfo and default policy values */
+ policy->governor = CPUFREQ_DEFAULT_GOVERNOR;
+ policy->cpuinfo.transition_latency = 1000000; /* 1ms */
+ policy->cur = cris_freq_get_cpu_frequency(0);
+
+ result = cpufreq_frequency_table_cpuinfo(policy, cris_freq_table);
+ if (result)
+ return (result);
+
+ cpufreq_frequency_table_get_attr(cris_freq_table, policy->cpu);
+
+ return 0;
+}
+
+
+static int cris_freq_cpu_exit(struct cpufreq_policy *policy)
+{
+ cpufreq_frequency_table_put_attr(policy->cpu);
+ return 0;
+}
+
+
+static struct freq_attr *cris_freq_attr[] = {
+ &cpufreq_freq_attr_scaling_available_freqs,
+ NULL,
+};
+
+static struct cpufreq_driver cris_freq_driver = {
+ .get = cris_freq_get_cpu_frequency,
+ .verify = cris_freq_verify,
+ .target = cris_freq_target,
+ .init = cris_freq_cpu_init,
+ .exit = cris_freq_cpu_exit,
+ .name = "cris_freq",
+ .owner = THIS_MODULE,
+ .attr = cris_freq_attr,
+};
+
+static int __init cris_freq_init(void)
+{
+ int ret;
+ ret = cpufreq_register_driver(&cris_freq_driver);
+ cpufreq_register_notifier(&cris_sdram_freq_notifier_block,
+ CPUFREQ_TRANSITION_NOTIFIER);
+ return ret;
+}
+
+static int
+cris_sdram_freq_notifier(struct notifier_block *nb, unsigned long val,
+ void *data)
+{
+ int i;
+ struct cpufreq_freqs *freqs = data;
+ if (val == CPUFREQ_PRECHANGE) {
+ reg_ddr2_rw_cfg cfg =
+ REG_RD(ddr2, regi_ddr2_ctrl, rw_cfg);
+ cfg.ref_interval = (freqs->new == 200000 ? 1560 : 46);
+
+ if (freqs->new == 200000)
+ for (i = 0; i < 50000; i++);
+ REG_WR(bif_core, regi_bif_core, rw_sdram_timing, timing);
+ }
+ return 0;
+}
+
+
+module_init(cris_freq_init);