112 lines
2.1 KiB
C
112 lines
2.1 KiB
C
/*
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* Copyright (C) 2012 Alexander Shiyan <shc_work@mail.ru>
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as
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* published by the Free Software Foundation; either version 2 of
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* the License, or (at your option) any later version.
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*/
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#include <common.h>
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#include <init.h>
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#include <clock.h>
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#include <asm/io.h>
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#include <linux/clkdev.h>
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#include <mach/clps711x.h>
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static struct clk {
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unsigned long rate;
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} uart_clk, bus_clk;
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static uint64_t clocksource_read(void)
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{
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return ~readw(TC2D);
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}
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static struct clocksource cs = {
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.read = clocksource_read,
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.mask = CLOCKSOURCE_MASK(16),
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};
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unsigned long clk_get_rate(struct clk *clk)
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{
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return clk->rate;
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}
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EXPORT_SYMBOL(clk_get_rate);
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int clk_enable(struct clk *clk)
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{
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/* Do nothing */
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return 0;
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}
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EXPORT_SYMBOL(clk_enable);
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void clk_disable(struct clk *clk)
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{
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/* Do nothing */
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}
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EXPORT_SYMBOL(clk_disable);
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static int clocks_init(void)
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{
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int osc, ext, pll, cpu, timer;
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u32 tmp;
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osc = 3686400;
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ext = 13000000;
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tmp = readl(PLLR) >> 24;
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if (tmp)
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pll = (osc * tmp) / 2;
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else
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pll = 73728000; /* Default value for old CPUs */
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tmp = readl(SYSFLG2);
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if (tmp & SYSFLG2_CKMODE) {
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cpu = ext;
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bus_clk.rate = cpu;
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} else {
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cpu = pll;
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if (cpu >= 36864000)
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bus_clk.rate = cpu / 2;
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else
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bus_clk.rate = 36864000 / 2;
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}
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uart_clk.rate = bus_clk.rate / 10;
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if (tmp & SYSFLG2_CKMODE) {
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tmp = readw(SYSCON2);
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if (tmp & SYSCON2_OSTB)
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timer = ext / 26;
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else
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timer = 541440;
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} else
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timer = cpu / 144;
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tmp = readl(SYSCON1);
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tmp &= ~SYSCON1_TC2M; /* Free running mode */
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tmp |= SYSCON1_TC2S; /* High frequency source */
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writel(tmp, SYSCON1);
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clocks_calc_mult_shift(&cs.mult, &cs.shift, timer, NSEC_PER_SEC, 10);
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return init_clock(&cs);
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}
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core_initcall(clocks_init);
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static struct clk_lookup clocks_lookups[] = {
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CLKDEV_CON_ID("bus", &bus_clk),
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CLKDEV_DEV_ID("clps711x_serial0", &uart_clk),
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CLKDEV_DEV_ID("clps711x_serial1", &uart_clk),
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};
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static int clkdev_init(void)
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{
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clkdev_add_table(clocks_lookups, ARRAY_SIZE(clocks_lookups));
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return 0;
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}
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postcore_initcall(clkdev_init);
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