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Diffstat (limited to 'arch/arm/mach-s3c/cpufreq-utils-s3c24xx.c')
-rw-r--r--arch/arm/mach-s3c/cpufreq-utils-s3c24xx.c94
1 files changed, 94 insertions, 0 deletions
diff --git a/arch/arm/mach-s3c/cpufreq-utils-s3c24xx.c b/arch/arm/mach-s3c/cpufreq-utils-s3c24xx.c
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+++ b/arch/arm/mach-s3c/cpufreq-utils-s3c24xx.c
@@ -0,0 +1,94 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// 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
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/cpufreq.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+
+#include "map.h"
+#include "regs-clock.h"
+
+#include <linux/soc/samsung/s3c-cpufreq-core.h>
+
+#include "regs-mem-s3c24xx.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);
+}
+
+#if defined(CONFIG_CPU_S3C2440) || defined(CONFIG_CPU_S3C2442)
+u32 s3c2440_read_camdivn(void)
+{
+ return __raw_readl(S3C2440_CAMDIVN);
+}
+
+void s3c2440_write_camdivn(u32 camdiv)
+{
+ __raw_writel(camdiv, S3C2440_CAMDIVN);
+}
+#endif
+
+u32 s3c24xx_read_clkdivn(void)
+{
+ return __raw_readl(S3C2410_CLKDIVN);
+}
+
+void s3c24xx_write_clkdivn(u32 clkdiv)
+{
+ __raw_writel(clkdiv, S3C2410_CLKDIVN);
+}
+
+u32 s3c24xx_read_mpllcon(void)
+{
+ return __raw_readl(S3C2410_MPLLCON);
+}
+
+void s3c24xx_write_locktime(u32 locktime)
+{
+ return __raw_writel(locktime, S3C2410_LOCKTIME);
+}