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 0000000000..6f26d626a7 --- /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(); +} |