44 lines
1.0 KiB
C
44 lines
1.0 KiB
C
// SPDX-License-Identifier: GPL-2.0+
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/*
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* (C) Copyright 2000-2004
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* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
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*/
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#include <common.h>
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#include <clock_legacy.h>
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#include <mpc8xx.h>
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#include <asm/processor.h>
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#include <asm/io.h>
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DECLARE_GLOBAL_DATA_PTR;
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/*
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* get_clocks() fills in gd->cpu_clock depending on CONFIG_8xx_GCLK_FREQ
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*/
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int get_clocks(void)
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{
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immap_t __iomem *immap = (immap_t __iomem *)CONFIG_SYS_IMMR;
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uint sccr = in_be32(&immap->im_clkrst.car_sccr);
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uint divider = 1 << (((sccr & SCCR_DFBRG11) >> 11) * 2);
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/*
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* If for some reason measuring the gclk frequency won't
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* work, we return the hardwired value.
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* (For example, the cogent CMA286-60 CPU module has no
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* separate oscillator for PITRTCLK)
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*/
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gd->cpu_clk = CONFIG_8xx_GCLK_FREQ;
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if ((sccr & SCCR_EBDF11) == 0) {
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/* No Bus Divider active */
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gd->bus_clk = gd->cpu_clk;
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} else {
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/* The MPC8xx has only one BDF: half clock speed */
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gd->bus_clk = gd->cpu_clk / 2;
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}
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gd->arch.brg_clk = gd->cpu_clk / divider;
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return 0;
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}
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