diff options
Diffstat (limited to 'arch/arm/cpu/arm926ejs/lpc32xx/clk.c')
| -rw-r--r-- | arch/arm/cpu/arm926ejs/lpc32xx/clk.c | 117 | 
1 files changed, 117 insertions, 0 deletions
| diff --git a/arch/arm/cpu/arm926ejs/lpc32xx/clk.c b/arch/arm/cpu/arm926ejs/lpc32xx/clk.c new file mode 100644 index 000000000..6f26d626a --- /dev/null +++ b/arch/arm/cpu/arm926ejs/lpc32xx/clk.c @@ -0,0 +1,117 @@ +/* + * Copyright (C) 2011 by Vladimir Zapolskiy <vz@mleia.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, + * MA 02110-1301, USA. + */ + +#include <common.h> +#include <div64.h> +#include <asm/arch/cpu.h> +#include <asm/arch/clk.h> +#include <asm/io.h> + +static struct clk_pm_regs *clk = (struct clk_pm_regs *)CLK_PM_BASE; + +unsigned int get_sys_clk_rate(void) +{ +	if (readl(&clk->sysclk_ctrl) & CLK_SYSCLK_PLL397) +		return RTC_CLK_FREQUENCY * 397; +	else +		return OSC_CLK_FREQUENCY; +} + +unsigned int get_hclk_pll_rate(void) +{ +	unsigned long long fin, fref, fcco, fout; +	u32 val, m_div, n_div, p_div; + +	/* +	 * Valid frequency ranges: +	 *     1 * 10^6 <=  Fin <=  20 * 10^6 +	 *     1 * 10^6 <= Fref <=  27 * 10^6 +	 *   156 * 10^6 <= Fcco <= 320 * 10^6 +	 */ + +	fref = fin = get_sys_clk_rate(); +	if (fin > 20000000ULL || fin < 1000000ULL) +		return 0; + +	val = readl(&clk->hclkpll_ctrl); +	m_div = ((val & CLK_HCLK_PLL_FEEDBACK_DIV_MASK) >> 1) + 1; +	n_div = ((val & CLK_HCLK_PLL_PREDIV_MASK) >> 9) + 1; +	if (val & CLK_HCLK_PLL_DIRECT) +		p_div = 0; +	else +		p_div = ((val & CLK_HCLK_PLL_POSTDIV_MASK) >> 11) + 1; +	p_div = 1 << p_div; + +	if (val & CLK_HCLK_PLL_BYPASS) { +		do_div(fin, p_div); +		return fin; +	} + +	do_div(fref, n_div); +	if (fref > 27000000ULL || fref < 1000000ULL) +		return 0; + +	fout = fref * m_div; +	if (val & CLK_HCLK_PLL_FEEDBACK) { +		fcco = fout; +		do_div(fout, p_div); +	} else +		fcco = fout * p_div; + +	if (fcco > 320000000ULL || fcco < 156000000ULL) +		return 0; + +	return fout; +} + +unsigned int get_hclk_clk_div(void) +{ +	u32 val; + +	val = readl(&clk->hclkdiv_ctrl) & CLK_HCLK_ARM_PLL_DIV_MASK; + +	return 1 << val; +} + +unsigned int get_hclk_clk_rate(void) +{ +	return get_hclk_pll_rate() / get_hclk_clk_div(); +} + +unsigned int get_periph_clk_div(void) +{ +	u32 val; + +	val = readl(&clk->hclkdiv_ctrl) & CLK_HCLK_PERIPH_DIV_MASK; + +	return (val >> 2) + 1; +} + +unsigned int get_periph_clk_rate(void) +{ +	if (!(readl(&clk->pwr_ctrl) & CLK_PWR_NORMAL_RUN)) +		return get_sys_clk_rate(); + +	return get_hclk_pll_rate() / get_periph_clk_div(); +} + +int get_serial_clock(void) +{ +	return get_periph_clk_rate(); +} |