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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/arch/arm/mach-s3c24xx/cpufreq-utils.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/arch/arm/mach-s3c24xx/cpufreq-utils.c')
-rw-r--r--kernel/arch/arm/mach-s3c24xx/cpufreq-utils.c66
1 files changed, 66 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-s3c24xx/cpufreq-utils.c b/kernel/arch/arm/mach-s3c24xx/cpufreq-utils.c
new file mode 100644
index 000000000..d4d951433
--- /dev/null
+++ b/kernel/arch/arm/mach-s3c24xx/cpufreq-utils.c
@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) 2009 Simtec Electronics
+ * http://armlinux.simtec.co.uk/
+ * Ben Dooks <ben@simtec.co.uk>
+ *
+ * S3C24XX CPU Frequency scaling - utils for S3C2410/S3C2440/S3C2442
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+*/
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/cpufreq.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+
+#include <mach/map.h>
+#include <mach/regs-clock.h>
+
+#include <plat/cpu-freq-core.h>
+
+#include "regs-mem.h"
+
+/**
+ * s3c2410_cpufreq_setrefresh - set SDRAM refresh value
+ * @cfg: The frequency configuration
+ *
+ * Set the SDRAM refresh value appropriately for the configured
+ * frequency.
+ */
+void s3c2410_cpufreq_setrefresh(struct s3c_cpufreq_config *cfg)
+{
+ struct s3c_cpufreq_board *board = cfg->board;
+ unsigned long refresh;
+ unsigned long refval;
+
+ /* Reduce both the refresh time (in ns) and the frequency (in MHz)
+ * down to ensure that we do not overflow 32 bit numbers.
+ *
+ * This should work for HCLK up to 133MHz and refresh period up
+ * to 30usec.
+ */
+
+ refresh = (cfg->freq.hclk / 100) * (board->refresh / 10);
+ refresh = DIV_ROUND_UP(refresh, (1000 * 1000)); /* apply scale */
+ refresh = (1 << 11) + 1 - refresh;
+
+ s3c_freq_dbg("%s: refresh value %lu\n", __func__, refresh);
+
+ refval = __raw_readl(S3C2410_REFRESH);
+ refval &= ~((1 << 12) - 1);
+ refval |= refresh;
+ __raw_writel(refval, S3C2410_REFRESH);
+}
+
+/**
+ * s3c2410_set_fvco - set the PLL value
+ * @cfg: The frequency configuration
+ */
+void s3c2410_set_fvco(struct s3c_cpufreq_config *cfg)
+{
+ if (!IS_ERR(cfg->mpll))
+ clk_set_rate(cfg->mpll, cfg->pll.frequency);
+}