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Diffstat (limited to 'arch/arm/cpu/arm926ejs/lpc32xx/clk.c')
-rw-r--r--arch/arm/cpu/arm926ejs/lpc32xx/clk.c117
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 0000000..6f26d62
--- /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();
+}
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