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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/drivers/cpufreq/cris-etraxfs-cpufreq.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/drivers/cpufreq/cris-etraxfs-cpufreq.c')
-rw-r--r--kernel/drivers/cpufreq/cris-etraxfs-cpufreq.c91
1 files changed, 91 insertions, 0 deletions
diff --git a/kernel/drivers/cpufreq/cris-etraxfs-cpufreq.c b/kernel/drivers/cpufreq/cris-etraxfs-cpufreq.c
new file mode 100644
index 000000000..22b2cdde7
--- /dev/null
+++ b/kernel/drivers/cpufreq/cris-etraxfs-cpufreq.c
@@ -0,0 +1,91 @@
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/cpufreq.h>
+#include <hwregs/reg_map.h>
+#include <arch/hwregs/reg_rdwr.h>
+#include <arch/hwregs/config_defs.h>
+#include <arch/hwregs/bif_core_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[] = {
+ {0, 0x01, 6000},
+ {0, 0x02, 200000},
+ {0, 0, CPUFREQ_TABLE_END},
+};
+
+static unsigned int cris_freq_get_cpu_frequency(unsigned int cpu)
+{
+ reg_config_rw_clk_ctrl clk_ctrl;
+ clk_ctrl = REG_RD(config, regi_config, rw_clk_ctrl);
+ return clk_ctrl.pll ? 200000 : 6000;
+}
+
+static int cris_freq_target(struct cpufreq_policy *policy, unsigned int state)
+{
+ reg_config_rw_clk_ctrl clk_ctrl;
+ clk_ctrl = REG_RD(config, regi_config, rw_clk_ctrl);
+
+ 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(config, regi_config, rw_clk_ctrl, clk_ctrl);
+
+ local_irq_enable();
+
+ return 0;
+}
+
+static int cris_freq_cpu_init(struct cpufreq_policy *policy)
+{
+ return cpufreq_generic_init(policy, cris_freq_table, 1000000);
+}
+
+static struct cpufreq_driver cris_freq_driver = {
+ .get = cris_freq_get_cpu_frequency,
+ .verify = cpufreq_generic_frequency_table_verify,
+ .target_index = cris_freq_target,
+ .init = cris_freq_cpu_init,
+ .name = "cris_freq",
+ .attr = cpufreq_generic_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_bif_core_rw_sdram_timing timing =
+ REG_RD(bif_core, regi_bif_core, rw_sdram_timing);
+ timing.cpd = (freqs->new == 200000 ? 0 : 1);
+
+ 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);