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f1f4b7703f
The OMAP3 clock code contains some legacy code to allow the MPU rate to be specified as a kernel command line parameter. If the 'mpurate' parameter is specified, the kernel will attempt to switch the MPU rate to this rate during boot. As part of this process, a short message "Switched to new clocking rate" is generated -- and in this message, the "Core" clock rate and "MPU" clock rate are transposed. This patch ensures that the clock rates are displayed in the correct order. Thanks to Bruno Guerin <br.guerin@free.fr> for reporting this bug and proposing a fix. Thanks to Richard Woodruff <r-woodruff2@ti.com> for reviewing the problem and passing the report on. Signed-off-by: Paul Walmsley <paul@pwsan.com> Cc: Bruno Guerin <br.guerin@free.fr> Cc: Richard Woodruff <r-woodruff2@ti.com>
105 lines
2.5 KiB
C
105 lines
2.5 KiB
C
/*
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* OMAP3-specific clock framework functions
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*
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* Copyright (C) 2007-2008 Texas Instruments, Inc.
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* Copyright (C) 2007-2010 Nokia Corporation
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*
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* Paul Walmsley
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* Jouni Högander
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*
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* Parts of this code are based on code written by
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* Richard Woodruff, Tony Lindgren, Tuukka Tikkanen, Karthik Dasu
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#undef DEBUG
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#include <linux/kernel.h>
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#include <linux/errno.h>
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#include <linux/clk.h>
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#include <linux/io.h>
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#include <plat/clock.h>
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#include "clock.h"
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#include "clock3xxx.h"
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#include "prm2xxx_3xxx.h"
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#include "prm-regbits-34xx.h"
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#include "cm2xxx_3xxx.h"
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#include "cm-regbits-34xx.h"
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/*
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* DPLL5_FREQ_FOR_USBHOST: USBHOST and USBTLL are the only clocks
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* that are sourced by DPLL5, and both of these require this clock
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* to be at 120 MHz for proper operation.
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*/
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#define DPLL5_FREQ_FOR_USBHOST 120000000
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/* needed by omap3_core_dpll_m2_set_rate() */
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struct clk *sdrc_ick_p, *arm_fck_p;
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int omap3_dpll4_set_rate(struct clk *clk, unsigned long rate)
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{
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/*
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* According to the 12-5 CDP code from TI, "Limitation 2.5"
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* on 3430ES1 prevents us from changing DPLL multipliers or dividers
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* on DPLL4.
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*/
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if (omap_rev() == OMAP3430_REV_ES1_0) {
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pr_err("clock: DPLL4 cannot change rate due to "
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"silicon 'Limitation 2.5' on 3430ES1.\n");
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return -EINVAL;
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}
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return omap3_noncore_dpll_set_rate(clk, rate);
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}
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void __init omap3_clk_lock_dpll5(void)
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{
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struct clk *dpll5_clk;
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struct clk *dpll5_m2_clk;
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dpll5_clk = clk_get(NULL, "dpll5_ck");
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clk_set_rate(dpll5_clk, DPLL5_FREQ_FOR_USBHOST);
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clk_enable(dpll5_clk);
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/* Enable autoidle to allow it to enter low power bypass */
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omap3_dpll_allow_idle(dpll5_clk);
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/* Program dpll5_m2_clk divider for no division */
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dpll5_m2_clk = clk_get(NULL, "dpll5_m2_ck");
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clk_enable(dpll5_m2_clk);
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clk_set_rate(dpll5_m2_clk, DPLL5_FREQ_FOR_USBHOST);
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clk_disable(dpll5_m2_clk);
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clk_disable(dpll5_clk);
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return;
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}
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/* Common clock code */
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/*
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* Switch the MPU rate if specified on cmdline. We cannot do this
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* early until cmdline is parsed. XXX This should be removed from the
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* clock code and handled by the OPP layer code in the near future.
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*/
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static int __init omap3xxx_clk_arch_init(void)
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{
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int ret;
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if (!cpu_is_omap34xx())
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return 0;
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ret = omap2_clk_switch_mpurate_at_boot("dpll1_ck");
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if (!ret)
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omap2_clk_print_new_rates("osc_sys_ck", "core_ck", "arm_fck");
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return ret;
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}
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arch_initcall(omap3xxx_clk_arch_init);
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