589 строки
15 KiB
C
589 строки
15 KiB
C
/***************************************************************************/
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/*
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* m53xx.c -- platform support for ColdFire 53xx based boards
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*
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* Copyright (C) 1999-2002, Greg Ungerer (gerg@snapgear.com)
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* Copyright (C) 2000, Lineo (www.lineo.com)
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* Yaroslav Vinogradov yaroslav.vinogradov@freescale.com
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* Copyright Freescale Semiconductor, Inc 2006
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* Copyright (c) 2006, emlix, Sebastian Hess <shess@hessware.de>
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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 as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*/
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/***************************************************************************/
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#include <linux/kernel.h>
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#include <linux/param.h>
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#include <linux/init.h>
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#include <linux/io.h>
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#include <asm/machdep.h>
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#include <asm/coldfire.h>
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#include <asm/mcfsim.h>
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#include <asm/mcfuart.h>
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#include <asm/mcfdma.h>
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#include <asm/mcfwdebug.h>
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#include <asm/mcfclk.h>
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/***************************************************************************/
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DEFINE_CLK(0, "flexbus", 2, MCF_CLK);
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DEFINE_CLK(0, "mcfcan.0", 8, MCF_CLK);
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DEFINE_CLK(0, "fec.0", 12, MCF_CLK);
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DEFINE_CLK(0, "edma", 17, MCF_CLK);
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DEFINE_CLK(0, "intc.0", 18, MCF_CLK);
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DEFINE_CLK(0, "intc.1", 19, MCF_CLK);
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DEFINE_CLK(0, "iack.0", 21, MCF_CLK);
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DEFINE_CLK(0, "mcfi2c.0", 22, MCF_CLK);
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DEFINE_CLK(0, "mcfqspi.0", 23, MCF_CLK);
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DEFINE_CLK(0, "mcfuart.0", 24, MCF_BUSCLK);
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DEFINE_CLK(0, "mcfuart.1", 25, MCF_BUSCLK);
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DEFINE_CLK(0, "mcfuart.2", 26, MCF_BUSCLK);
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DEFINE_CLK(0, "mcftmr.0", 28, MCF_CLK);
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DEFINE_CLK(0, "mcftmr.1", 29, MCF_CLK);
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DEFINE_CLK(0, "mcftmr.2", 30, MCF_CLK);
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DEFINE_CLK(0, "mcftmr.3", 31, MCF_CLK);
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DEFINE_CLK(0, "mcfpit.0", 32, MCF_CLK);
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DEFINE_CLK(0, "mcfpit.1", 33, MCF_CLK);
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DEFINE_CLK(0, "mcfpit.2", 34, MCF_CLK);
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DEFINE_CLK(0, "mcfpit.3", 35, MCF_CLK);
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DEFINE_CLK(0, "mcfpwm.0", 36, MCF_CLK);
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DEFINE_CLK(0, "mcfeport.0", 37, MCF_CLK);
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DEFINE_CLK(0, "mcfwdt.0", 38, MCF_CLK);
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DEFINE_CLK(0, "sys.0", 40, MCF_BUSCLK);
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DEFINE_CLK(0, "gpio.0", 41, MCF_BUSCLK);
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DEFINE_CLK(0, "mcfrtc.0", 42, MCF_CLK);
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DEFINE_CLK(0, "mcflcd.0", 43, MCF_CLK);
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DEFINE_CLK(0, "mcfusb-otg.0", 44, MCF_CLK);
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DEFINE_CLK(0, "mcfusb-host.0", 45, MCF_CLK);
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DEFINE_CLK(0, "sdram.0", 46, MCF_CLK);
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DEFINE_CLK(0, "ssi.0", 47, MCF_CLK);
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DEFINE_CLK(0, "pll.0", 48, MCF_CLK);
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DEFINE_CLK(1, "mdha.0", 32, MCF_CLK);
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DEFINE_CLK(1, "skha.0", 33, MCF_CLK);
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DEFINE_CLK(1, "rng.0", 34, MCF_CLK);
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struct clk *mcf_clks[] = {
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&__clk_0_2, /* flexbus */
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&__clk_0_8, /* mcfcan.0 */
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&__clk_0_12, /* fec.0 */
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&__clk_0_17, /* edma */
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&__clk_0_18, /* intc.0 */
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&__clk_0_19, /* intc.1 */
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&__clk_0_21, /* iack.0 */
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&__clk_0_22, /* mcfi2c.0 */
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&__clk_0_23, /* mcfqspi.0 */
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&__clk_0_24, /* mcfuart.0 */
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&__clk_0_25, /* mcfuart.1 */
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&__clk_0_26, /* mcfuart.2 */
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&__clk_0_28, /* mcftmr.0 */
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&__clk_0_29, /* mcftmr.1 */
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&__clk_0_30, /* mcftmr.2 */
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&__clk_0_31, /* mcftmr.3 */
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&__clk_0_32, /* mcfpit.0 */
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&__clk_0_33, /* mcfpit.1 */
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&__clk_0_34, /* mcfpit.2 */
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&__clk_0_35, /* mcfpit.3 */
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&__clk_0_36, /* mcfpwm.0 */
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&__clk_0_37, /* mcfeport.0 */
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&__clk_0_38, /* mcfwdt.0 */
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&__clk_0_40, /* sys.0 */
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&__clk_0_41, /* gpio.0 */
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&__clk_0_42, /* mcfrtc.0 */
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&__clk_0_43, /* mcflcd.0 */
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&__clk_0_44, /* mcfusb-otg.0 */
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&__clk_0_45, /* mcfusb-host.0 */
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&__clk_0_46, /* sdram.0 */
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&__clk_0_47, /* ssi.0 */
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&__clk_0_48, /* pll.0 */
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&__clk_1_32, /* mdha.0 */
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&__clk_1_33, /* skha.0 */
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&__clk_1_34, /* rng.0 */
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NULL,
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};
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static struct clk * const enable_clks[] __initconst = {
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&__clk_0_2, /* flexbus */
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&__clk_0_18, /* intc.0 */
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&__clk_0_19, /* intc.1 */
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&__clk_0_21, /* iack.0 */
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&__clk_0_24, /* mcfuart.0 */
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&__clk_0_25, /* mcfuart.1 */
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&__clk_0_26, /* mcfuart.2 */
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&__clk_0_28, /* mcftmr.0 */
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&__clk_0_29, /* mcftmr.1 */
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&__clk_0_32, /* mcfpit.0 */
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&__clk_0_33, /* mcfpit.1 */
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&__clk_0_37, /* mcfeport.0 */
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&__clk_0_40, /* sys.0 */
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&__clk_0_41, /* gpio.0 */
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&__clk_0_46, /* sdram.0 */
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&__clk_0_48, /* pll.0 */
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};
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static struct clk * const disable_clks[] __initconst = {
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&__clk_0_8, /* mcfcan.0 */
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&__clk_0_12, /* fec.0 */
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&__clk_0_17, /* edma */
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&__clk_0_22, /* mcfi2c.0 */
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&__clk_0_23, /* mcfqspi.0 */
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&__clk_0_30, /* mcftmr.2 */
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&__clk_0_31, /* mcftmr.3 */
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&__clk_0_34, /* mcfpit.2 */
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&__clk_0_35, /* mcfpit.3 */
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&__clk_0_36, /* mcfpwm.0 */
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&__clk_0_38, /* mcfwdt.0 */
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&__clk_0_42, /* mcfrtc.0 */
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&__clk_0_43, /* mcflcd.0 */
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&__clk_0_44, /* mcfusb-otg.0 */
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&__clk_0_45, /* mcfusb-host.0 */
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&__clk_0_47, /* ssi.0 */
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&__clk_1_32, /* mdha.0 */
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&__clk_1_33, /* skha.0 */
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&__clk_1_34, /* rng.0 */
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};
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static void __init m53xx_clk_init(void)
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{
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unsigned i;
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/* make sure these clocks are enabled */
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for (i = 0; i < ARRAY_SIZE(enable_clks); ++i)
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__clk_init_enabled(enable_clks[i]);
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/* make sure these clocks are disabled */
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for (i = 0; i < ARRAY_SIZE(disable_clks); ++i)
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__clk_init_disabled(disable_clks[i]);
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}
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/***************************************************************************/
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static void __init m53xx_qspi_init(void)
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{
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#if IS_ENABLED(CONFIG_SPI_COLDFIRE_QSPI)
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/* setup QSPS pins for QSPI with gpio CS control */
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writew(0x01f0, MCFGPIO_PAR_QSPI);
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#endif /* IS_ENABLED(CONFIG_SPI_COLDFIRE_QSPI) */
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}
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/***************************************************************************/
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static void __init m53xx_uarts_init(void)
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{
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/* UART GPIO initialization */
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writew(readw(MCFGPIO_PAR_UART) | 0x0FFF, MCFGPIO_PAR_UART);
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}
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/***************************************************************************/
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static void __init m53xx_fec_init(void)
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{
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u8 v;
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/* Set multi-function pins to ethernet mode for fec0 */
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v = readb(MCFGPIO_PAR_FECI2C);
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v |= MCF_GPIO_PAR_FECI2C_PAR_MDC_EMDC |
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MCF_GPIO_PAR_FECI2C_PAR_MDIO_EMDIO;
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writeb(v, MCFGPIO_PAR_FECI2C);
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v = readb(MCFGPIO_PAR_FEC);
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v = MCF_GPIO_PAR_FEC_PAR_FEC_7W_FEC | MCF_GPIO_PAR_FEC_PAR_FEC_MII_FEC;
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writeb(v, MCFGPIO_PAR_FEC);
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}
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/***************************************************************************/
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void __init config_BSP(char *commandp, int size)
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{
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#if !defined(CONFIG_BOOTPARAM)
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/* Copy command line from FLASH to local buffer... */
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memcpy(commandp, (char *) 0x4000, 4);
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if(strncmp(commandp, "kcl ", 4) == 0){
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memcpy(commandp, (char *) 0x4004, size);
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commandp[size-1] = 0;
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} else {
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memset(commandp, 0, size);
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}
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#endif
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mach_sched_init = hw_timer_init;
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m53xx_clk_init();
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m53xx_uarts_init();
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m53xx_fec_init();
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m53xx_qspi_init();
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#ifdef CONFIG_BDM_DISABLE
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/*
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* Disable the BDM clocking. This also turns off most of the rest of
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* the BDM device. This is good for EMC reasons. This option is not
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* incompatible with the memory protection option.
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*/
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wdebug(MCFDEBUG_CSR, MCFDEBUG_CSR_PSTCLK);
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#endif
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}
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/***************************************************************************/
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/* Board initialization */
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/***************************************************************************/
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/*
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* PLL min/max specifications
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*/
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#define MAX_FVCO 500000 /* KHz */
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#define MAX_FSYS 80000 /* KHz */
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#define MIN_FSYS 58333 /* KHz */
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#define FREF 16000 /* KHz */
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#define MAX_MFD 135 /* Multiplier */
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#define MIN_MFD 88 /* Multiplier */
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#define BUSDIV 6 /* Divider */
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/*
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* Low Power Divider specifications
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*/
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#define MIN_LPD (1 << 0) /* Divider (not encoded) */
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#define MAX_LPD (1 << 15) /* Divider (not encoded) */
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#define DEFAULT_LPD (1 << 1) /* Divider (not encoded) */
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#define SYS_CLK_KHZ 80000
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#define SYSTEM_PERIOD 12.5
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/*
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* SDRAM Timing Parameters
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*/
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#define SDRAM_BL 8 /* # of beats in a burst */
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#define SDRAM_TWR 2 /* in clocks */
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#define SDRAM_CASL 2.5 /* CASL in clocks */
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#define SDRAM_TRCD 2 /* in clocks */
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#define SDRAM_TRP 2 /* in clocks */
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#define SDRAM_TRFC 7 /* in clocks */
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#define SDRAM_TREFI 7800 /* in ns */
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#define EXT_SRAM_ADDRESS (0xC0000000)
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#define FLASH_ADDRESS (0x00000000)
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#define SDRAM_ADDRESS (0x40000000)
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#define NAND_FLASH_ADDRESS (0xD0000000)
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int sys_clk_khz = 0;
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int sys_clk_mhz = 0;
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void wtm_init(void);
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void scm_init(void);
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void gpio_init(void);
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void fbcs_init(void);
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void sdramc_init(void);
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int clock_pll (int fsys, int flags);
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int clock_limp (int);
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int clock_exit_limp (void);
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int get_sys_clock (void);
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asmlinkage void __init sysinit(void)
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{
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sys_clk_khz = clock_pll(0, 0);
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sys_clk_mhz = sys_clk_khz/1000;
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wtm_init();
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scm_init();
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gpio_init();
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fbcs_init();
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sdramc_init();
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}
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void wtm_init(void)
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{
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/* Disable watchdog timer */
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writew(0, MCF_WTM_WCR);
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}
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#define MCF_SCM_BCR_GBW (0x00000100)
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#define MCF_SCM_BCR_GBR (0x00000200)
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void scm_init(void)
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{
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/* All masters are trusted */
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writel(0x77777777, MCF_SCM_MPR);
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/* Allow supervisor/user, read/write, and trusted/untrusted
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access to all slaves */
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writel(0, MCF_SCM_PACRA);
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writel(0, MCF_SCM_PACRB);
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writel(0, MCF_SCM_PACRC);
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writel(0, MCF_SCM_PACRD);
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writel(0, MCF_SCM_PACRE);
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writel(0, MCF_SCM_PACRF);
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/* Enable bursts */
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writel(MCF_SCM_BCR_GBR | MCF_SCM_BCR_GBW, MCF_SCM_BCR);
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}
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void fbcs_init(void)
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{
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writeb(0x3E, MCFGPIO_PAR_CS);
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/* Latch chip select */
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writel(0x10080000, MCF_FBCS1_CSAR);
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writel(0x002A3780, MCF_FBCS1_CSCR);
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writel(MCF_FBCS_CSMR_BAM_2M | MCF_FBCS_CSMR_V, MCF_FBCS1_CSMR);
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/* Initialize latch to drive signals to inactive states */
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writew(0xffff, 0x10080000);
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/* External SRAM */
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writel(EXT_SRAM_ADDRESS, MCF_FBCS1_CSAR);
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writel(MCF_FBCS_CSCR_PS_16 |
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MCF_FBCS_CSCR_AA |
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MCF_FBCS_CSCR_SBM |
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MCF_FBCS_CSCR_WS(1),
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MCF_FBCS1_CSCR);
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writel(MCF_FBCS_CSMR_BAM_512K | MCF_FBCS_CSMR_V, MCF_FBCS1_CSMR);
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/* Boot Flash connected to FBCS0 */
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writel(FLASH_ADDRESS, MCF_FBCS0_CSAR);
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writel(MCF_FBCS_CSCR_PS_16 |
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MCF_FBCS_CSCR_BEM |
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MCF_FBCS_CSCR_AA |
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MCF_FBCS_CSCR_SBM |
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MCF_FBCS_CSCR_WS(7),
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MCF_FBCS0_CSCR);
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writel(MCF_FBCS_CSMR_BAM_32M | MCF_FBCS_CSMR_V, MCF_FBCS0_CSMR);
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}
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void sdramc_init(void)
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{
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/*
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* Check to see if the SDRAM has already been initialized
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* by a run control tool
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*/
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if (!(readl(MCF_SDRAMC_SDCR) & MCF_SDRAMC_SDCR_REF)) {
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/* SDRAM chip select initialization */
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/* Initialize SDRAM chip select */
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writel(MCF_SDRAMC_SDCS_BA(SDRAM_ADDRESS) |
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MCF_SDRAMC_SDCS_CSSZ(MCF_SDRAMC_SDCS_CSSZ_32MBYTE),
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MCF_SDRAMC_SDCS0);
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/*
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* Basic configuration and initialization
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*/
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writel(MCF_SDRAMC_SDCFG1_SRD2RW((int)((SDRAM_CASL + 2) + 0.5)) |
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MCF_SDRAMC_SDCFG1_SWT2RD(SDRAM_TWR + 1) |
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MCF_SDRAMC_SDCFG1_RDLAT((int)((SDRAM_CASL * 2) + 2)) |
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MCF_SDRAMC_SDCFG1_ACT2RW((int)(SDRAM_TRCD + 0.5)) |
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MCF_SDRAMC_SDCFG1_PRE2ACT((int)(SDRAM_TRP + 0.5)) |
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MCF_SDRAMC_SDCFG1_REF2ACT((int)(SDRAM_TRFC + 0.5)) |
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MCF_SDRAMC_SDCFG1_WTLAT(3),
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MCF_SDRAMC_SDCFG1);
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writel(MCF_SDRAMC_SDCFG2_BRD2PRE(SDRAM_BL / 2 + 1) |
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MCF_SDRAMC_SDCFG2_BWT2RW(SDRAM_BL / 2 + SDRAM_TWR) |
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MCF_SDRAMC_SDCFG2_BRD2WT((int)((SDRAM_CASL + SDRAM_BL / 2 - 1.0) + 0.5)) |
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MCF_SDRAMC_SDCFG2_BL(SDRAM_BL - 1),
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MCF_SDRAMC_SDCFG2);
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/*
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* Precharge and enable write to SDMR
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*/
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writel(MCF_SDRAMC_SDCR_MODE_EN |
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MCF_SDRAMC_SDCR_CKE |
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MCF_SDRAMC_SDCR_DDR |
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MCF_SDRAMC_SDCR_MUX(1) |
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MCF_SDRAMC_SDCR_RCNT((int)(((SDRAM_TREFI / (SYSTEM_PERIOD * 64)) - 1) + 0.5)) |
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MCF_SDRAMC_SDCR_PS_16 |
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MCF_SDRAMC_SDCR_IPALL,
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MCF_SDRAMC_SDCR);
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/*
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* Write extended mode register
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*/
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writel(MCF_SDRAMC_SDMR_BNKAD_LEMR |
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MCF_SDRAMC_SDMR_AD(0x0) |
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MCF_SDRAMC_SDMR_CMD,
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MCF_SDRAMC_SDMR);
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/*
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* Write mode register and reset DLL
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*/
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writel(MCF_SDRAMC_SDMR_BNKAD_LMR |
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MCF_SDRAMC_SDMR_AD(0x163) |
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MCF_SDRAMC_SDMR_CMD,
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MCF_SDRAMC_SDMR);
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/*
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* Execute a PALL command
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*/
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writel(readl(MCF_SDRAMC_SDCR) | MCF_SDRAMC_SDCR_IPALL, MCF_SDRAMC_SDCR);
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/*
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* Perform two REF cycles
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*/
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writel(readl(MCF_SDRAMC_SDCR) | MCF_SDRAMC_SDCR_IREF, MCF_SDRAMC_SDCR);
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writel(readl(MCF_SDRAMC_SDCR) | MCF_SDRAMC_SDCR_IREF, MCF_SDRAMC_SDCR);
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/*
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* Write mode register and clear reset DLL
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*/
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writel(MCF_SDRAMC_SDMR_BNKAD_LMR |
|
|
MCF_SDRAMC_SDMR_AD(0x063) |
|
|
MCF_SDRAMC_SDMR_CMD,
|
|
MCF_SDRAMC_SDMR);
|
|
|
|
/*
|
|
* Enable auto refresh and lock SDMR
|
|
*/
|
|
writel(readl(MCF_SDRAMC_SDCR) & ~MCF_SDRAMC_SDCR_MODE_EN,
|
|
MCF_SDRAMC_SDCR);
|
|
writel(MCF_SDRAMC_SDCR_REF | MCF_SDRAMC_SDCR_DQS_OE(0xC),
|
|
MCF_SDRAMC_SDCR);
|
|
}
|
|
}
|
|
|
|
void gpio_init(void)
|
|
{
|
|
/* Enable UART0 pins */
|
|
writew(MCF_GPIO_PAR_UART_PAR_URXD0 | MCF_GPIO_PAR_UART_PAR_UTXD0,
|
|
MCFGPIO_PAR_UART);
|
|
|
|
/*
|
|
* Initialize TIN3 as a GPIO output to enable the write
|
|
* half of the latch.
|
|
*/
|
|
writeb(0x00, MCFGPIO_PAR_TIMER);
|
|
writeb(0x08, MCFGPIO_PDDR_TIMER);
|
|
writeb(0x00, MCFGPIO_PCLRR_TIMER);
|
|
}
|
|
|
|
int clock_pll(int fsys, int flags)
|
|
{
|
|
int fref, temp, fout, mfd;
|
|
u32 i;
|
|
|
|
fref = FREF;
|
|
|
|
if (fsys == 0) {
|
|
/* Return current PLL output */
|
|
mfd = readb(MCF_PLL_PFDR);
|
|
|
|
return (fref * mfd / (BUSDIV * 4));
|
|
}
|
|
|
|
/* Check bounds of requested system clock */
|
|
if (fsys > MAX_FSYS)
|
|
fsys = MAX_FSYS;
|
|
if (fsys < MIN_FSYS)
|
|
fsys = MIN_FSYS;
|
|
|
|
/* Multiplying by 100 when calculating the temp value,
|
|
and then dividing by 100 to calculate the mfd allows
|
|
for exact values without needing to include floating
|
|
point libraries. */
|
|
temp = 100 * fsys / fref;
|
|
mfd = 4 * BUSDIV * temp / 100;
|
|
|
|
/* Determine the output frequency for selected values */
|
|
fout = (fref * mfd / (BUSDIV * 4));
|
|
|
|
/*
|
|
* Check to see if the SDRAM has already been initialized.
|
|
* If it has then the SDRAM needs to be put into self refresh
|
|
* mode before reprogramming the PLL.
|
|
*/
|
|
if (readl(MCF_SDRAMC_SDCR) & MCF_SDRAMC_SDCR_REF)
|
|
/* Put SDRAM into self refresh mode */
|
|
writel(readl(MCF_SDRAMC_SDCR) & ~MCF_SDRAMC_SDCR_CKE,
|
|
MCF_SDRAMC_SDCR);
|
|
|
|
/*
|
|
* Initialize the PLL to generate the new system clock frequency.
|
|
* The device must be put into LIMP mode to reprogram the PLL.
|
|
*/
|
|
|
|
/* Enter LIMP mode */
|
|
clock_limp(DEFAULT_LPD);
|
|
|
|
/* Reprogram PLL for desired fsys */
|
|
writeb(MCF_PLL_PODR_CPUDIV(BUSDIV/3) | MCF_PLL_PODR_BUSDIV(BUSDIV),
|
|
MCF_PLL_PODR);
|
|
|
|
writeb(mfd, MCF_PLL_PFDR);
|
|
|
|
/* Exit LIMP mode */
|
|
clock_exit_limp();
|
|
|
|
/*
|
|
* Return the SDRAM to normal operation if it is in use.
|
|
*/
|
|
if (readl(MCF_SDRAMC_SDCR) & MCF_SDRAMC_SDCR_REF)
|
|
/* Exit self refresh mode */
|
|
writel(readl(MCF_SDRAMC_SDCR) | MCF_SDRAMC_SDCR_CKE,
|
|
MCF_SDRAMC_SDCR);
|
|
|
|
/* Errata - workaround for SDRAM opeartion after exiting LIMP mode */
|
|
writel(MCF_SDRAMC_REFRESH, MCF_SDRAMC_LIMP_FIX);
|
|
|
|
/* wait for DQS logic to relock */
|
|
for (i = 0; i < 0x200; i++)
|
|
;
|
|
|
|
return fout;
|
|
}
|
|
|
|
int clock_limp(int div)
|
|
{
|
|
u32 temp;
|
|
|
|
/* Check bounds of divider */
|
|
if (div < MIN_LPD)
|
|
div = MIN_LPD;
|
|
if (div > MAX_LPD)
|
|
div = MAX_LPD;
|
|
|
|
/* Save of the current value of the SSIDIV so we don't
|
|
overwrite the value*/
|
|
temp = readw(MCF_CCM_CDR) & MCF_CCM_CDR_SSIDIV(0xF);
|
|
|
|
/* Apply the divider to the system clock */
|
|
writew(MCF_CCM_CDR_LPDIV(div) | MCF_CCM_CDR_SSIDIV(temp), MCF_CCM_CDR);
|
|
|
|
writew(readw(MCF_CCM_MISCCR) | MCF_CCM_MISCCR_LIMP, MCF_CCM_MISCCR);
|
|
|
|
return (FREF/(3*(1 << div)));
|
|
}
|
|
|
|
int clock_exit_limp(void)
|
|
{
|
|
int fout;
|
|
|
|
/* Exit LIMP mode */
|
|
writew(readw(MCF_CCM_MISCCR) & ~MCF_CCM_MISCCR_LIMP, MCF_CCM_MISCCR);
|
|
|
|
/* Wait for PLL to lock */
|
|
while (!(readw(MCF_CCM_MISCCR) & MCF_CCM_MISCCR_PLL_LOCK))
|
|
;
|
|
|
|
fout = get_sys_clock();
|
|
|
|
return fout;
|
|
}
|
|
|
|
int get_sys_clock(void)
|
|
{
|
|
int divider;
|
|
|
|
/* Test to see if device is in LIMP mode */
|
|
if (readw(MCF_CCM_MISCCR) & MCF_CCM_MISCCR_LIMP) {
|
|
divider = readw(MCF_CCM_CDR) & MCF_CCM_CDR_LPDIV(0xF);
|
|
return (FREF/(2 << divider));
|
|
}
|
|
else
|
|
return (FREF * readb(MCF_PLL_PFDR)) / (BUSDIV * 4);
|
|
}
|