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+/* linux/arch/arm/plat-s3c24xx/s3c2410-iotiming.c
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+ *
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+ * Copyright (c) 2006-2009 Simtec Electronics
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+ * http://armlinux.simtec.co.uk/
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+ * Ben Dooks <ben@simtec.co.uk>
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+ *
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+ * S3C24XX CPU Frequency scaling - IO timing for S3C2410/S3C2440/S3C2442
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+ *
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+ * This program is free software; you can redistribute it and/or modify
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+ * it under the terms of the GNU General Public License version 2 as
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+ * published by the Free Software Foundation.
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+*/
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+
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+#include <linux/init.h>
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+#include <linux/kernel.h>
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+#include <linux/errno.h>
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+#include <linux/cpufreq.h>
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+#include <linux/seq_file.h>
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+#include <linux/io.h>
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+#include <linux/slab.h>
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+
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+#include <mach/map.h>
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+#include <mach/regs-mem.h>
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+#include <mach/regs-clock.h>
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+
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+#include <plat/cpu-freq-core.h>
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+
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+#define print_ns(x) ((x) / 10), ((x) % 10)
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+
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+/**
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+ * s3c2410_print_timing - print bank timing data for debug purposes
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+ * @pfx: The prefix to put on the output
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+ * @timings: The timing inforamtion to print.
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+*/
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+static void s3c2410_print_timing(const char *pfx,
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+ struct s3c_iotimings *timings)
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+{
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+ struct s3c2410_iobank_timing *bt;
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+ int bank;
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+
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+ for (bank = 0; bank < MAX_BANKS; bank++) {
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+ bt = timings->bank[bank].io_2410;
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+ if (!bt)
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+ continue;
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+
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+ printk(KERN_DEBUG "%s %d: Tacs=%d.%d, Tcos=%d.%d, Tacc=%d.%d, "
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+ "Tcoh=%d.%d, Tcah=%d.%d\n", pfx, bank,
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+ print_ns(bt->tacs),
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+ print_ns(bt->tcos),
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+ print_ns(bt->tacc),
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+ print_ns(bt->tcoh),
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+ print_ns(bt->tcah));
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+ }
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+}
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+
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+/**
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+ * bank_reg - convert bank number to pointer to the control register.
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+ * @bank: The IO bank number.
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+ */
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+static inline void __iomem *bank_reg(unsigned int bank)
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+{
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+ return S3C2410_BANKCON0 + (bank << 2);
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+}
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+
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+/**
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+ * bank_is_io - test whether bank is used for IO
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+ * @bankcon: The bank control register.
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+ *
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+ * This is a simplistic test to see if any BANKCON[x] is not an IO
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+ * bank. It currently does not take into account whether BWSCON has
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+ * an illegal width-setting in it, or if the pin connected to nCS[x]
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+ * is actually being handled as a chip-select.
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+ */
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+static inline int bank_is_io(unsigned long bankcon)
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+{
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+ return !(bankcon & S3C2410_BANKCON_SDRAM);
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+}
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+
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+/**
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+ * to_div - convert cycle time to divisor
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+ * @cyc: The cycle time, in 10ths of nanoseconds.
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+ * @hclk_tns: The cycle time for HCLK, in 10ths of nanoseconds.
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+ *
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+ * Convert the given cycle time into the divisor to use to obtain it from
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+ * HCLK.
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+*/
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+static inline unsigned int to_div(unsigned int cyc, unsigned int hclk_tns)
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+{
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+ if (cyc == 0)
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+ return 0;
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+
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+ return DIV_ROUND_UP(cyc, hclk_tns);
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+}
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+
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+/**
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+ * calc_0124 - calculate divisor control for divisors that do /0, /1. /2 and /4
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+ * @cyc: The cycle time, in 10ths of nanoseconds.
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+ * @hclk_tns: The cycle time for HCLK, in 10ths of nanoseconds.
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+ * @v: Pointer to register to alter.
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+ * @shift: The shift to get to the control bits.
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+ *
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+ * Calculate the divisor, and turn it into the correct control bits to
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+ * set in the result, @v.
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+ */
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+static unsigned int calc_0124(unsigned int cyc, unsigned long hclk_tns,
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+ unsigned long *v, int shift)
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+{
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+ unsigned int div = to_div(cyc, hclk_tns);
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+ unsigned long val;
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+
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+ s3c_freq_iodbg("%s: cyc=%d, hclk=%lu, shift=%d => div %d\n",
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+ __func__, cyc, hclk_tns, shift, div);
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+
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+ switch (div) {
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+ case 0:
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+ val = 0;
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+ break;
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+ case 1:
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+ val = 1;
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+ break;
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+ case 2:
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+ val = 2;
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+ break;
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+ case 3:
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+ case 4:
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+ val = 3;
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+ break;
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+ default:
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+ return -1;
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+ }
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+
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+ *v |= val << shift;
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+ return 0;
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+}
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+
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+int calc_tacp(unsigned int cyc, unsigned long hclk, unsigned long *v)
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+{
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+ /* Currently no support for Tacp calculations. */
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+ return 0;
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+}
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+
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+/**
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+ * calc_tacc - calculate divisor control for tacc.
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+ * @cyc: The cycle time, in 10ths of nanoseconds.
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+ * @nwait_en: IS nWAIT enabled for this bank.
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+ * @hclk_tns: The cycle time for HCLK, in 10ths of nanoseconds.
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+ * @v: Pointer to register to alter.
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+ *
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+ * Calculate the divisor control for tACC, taking into account whether
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+ * the bank has nWAIT enabled. The result is used to modify the value
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+ * pointed to by @v.
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+*/
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+static int calc_tacc(unsigned int cyc, int nwait_en,
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+ unsigned long hclk_tns, unsigned long *v)
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+{
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+ unsigned int div = to_div(cyc, hclk_tns);
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