[Feature]add MT2731_MP2_MR2_SVN388 baseline version
Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/kernel/linux/v4.14/arch/m68k/coldfire/m53xx.c b/src/kernel/linux/v4.14/arch/m68k/coldfire/m53xx.c
new file mode 100644
index 0000000..cf19179
--- /dev/null
+++ b/src/kernel/linux/v4.14/arch/m68k/coldfire/m53xx.c
@@ -0,0 +1,598 @@
+/***************************************************************************/
+
+/*
+ * m53xx.c -- platform support for ColdFire 53xx based boards
+ *
+ * Copyright (C) 1999-2002, Greg Ungerer (gerg@snapgear.com)
+ * Copyright (C) 2000, Lineo (www.lineo.com)
+ * Yaroslav Vinogradov yaroslav.vinogradov@freescale.com
+ * Copyright Freescale Semiconductor, Inc 2006
+ * Copyright (c) 2006, emlix, Sebastian Hess <shess@hessware.de>
+ *
+ * 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.
+ */
+
+/***************************************************************************/
+
+#include <linux/kernel.h>
+#include <linux/param.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <asm/machdep.h>
+#include <asm/coldfire.h>
+#include <asm/mcfsim.h>
+#include <asm/mcfuart.h>
+#include <asm/mcfdma.h>
+#include <asm/mcfwdebug.h>
+#include <asm/mcfclk.h>
+
+/***************************************************************************/
+
+DEFINE_CLK(0, "flexbus", 2, MCF_CLK);
+DEFINE_CLK(0, "mcfcan.0", 8, MCF_CLK);
+DEFINE_CLK(0, "fec.0", 12, MCF_CLK);
+DEFINE_CLK(0, "edma", 17, MCF_CLK);
+DEFINE_CLK(0, "intc.0", 18, MCF_CLK);
+DEFINE_CLK(0, "intc.1", 19, MCF_CLK);
+DEFINE_CLK(0, "iack.0", 21, MCF_CLK);
+DEFINE_CLK(0, "imx1-i2c.0", 22, MCF_CLK);
+DEFINE_CLK(0, "mcfqspi.0", 23, MCF_CLK);
+DEFINE_CLK(0, "mcfuart.0", 24, MCF_BUSCLK);
+DEFINE_CLK(0, "mcfuart.1", 25, MCF_BUSCLK);
+DEFINE_CLK(0, "mcfuart.2", 26, MCF_BUSCLK);
+DEFINE_CLK(0, "mcftmr.0", 28, MCF_CLK);
+DEFINE_CLK(0, "mcftmr.1", 29, MCF_CLK);
+DEFINE_CLK(0, "mcftmr.2", 30, MCF_CLK);
+DEFINE_CLK(0, "mcftmr.3", 31, MCF_CLK);
+
+DEFINE_CLK(0, "mcfpit.0", 32, MCF_CLK);
+DEFINE_CLK(0, "mcfpit.1", 33, MCF_CLK);
+DEFINE_CLK(0, "mcfpit.2", 34, MCF_CLK);
+DEFINE_CLK(0, "mcfpit.3", 35, MCF_CLK);
+DEFINE_CLK(0, "mcfpwm.0", 36, MCF_CLK);
+DEFINE_CLK(0, "mcfeport.0", 37, MCF_CLK);
+DEFINE_CLK(0, "mcfwdt.0", 38, MCF_CLK);
+DEFINE_CLK(0, "sys.0", 40, MCF_BUSCLK);
+DEFINE_CLK(0, "gpio.0", 41, MCF_BUSCLK);
+DEFINE_CLK(0, "mcfrtc.0", 42, MCF_CLK);
+DEFINE_CLK(0, "mcflcd.0", 43, MCF_CLK);
+DEFINE_CLK(0, "mcfusb-otg.0", 44, MCF_CLK);
+DEFINE_CLK(0, "mcfusb-host.0", 45, MCF_CLK);
+DEFINE_CLK(0, "sdram.0", 46, MCF_CLK);
+DEFINE_CLK(0, "ssi.0", 47, MCF_CLK);
+DEFINE_CLK(0, "pll.0", 48, MCF_CLK);
+
+DEFINE_CLK(1, "mdha.0", 32, MCF_CLK);
+DEFINE_CLK(1, "skha.0", 33, MCF_CLK);
+DEFINE_CLK(1, "rng.0", 34, MCF_CLK);
+
+struct clk *mcf_clks[] = {
+ &__clk_0_2, /* flexbus */
+ &__clk_0_8, /* mcfcan.0 */
+ &__clk_0_12, /* fec.0 */
+ &__clk_0_17, /* edma */
+ &__clk_0_18, /* intc.0 */
+ &__clk_0_19, /* intc.1 */
+ &__clk_0_21, /* iack.0 */
+ &__clk_0_22, /* imx1-i2c.0 */
+ &__clk_0_23, /* mcfqspi.0 */
+ &__clk_0_24, /* mcfuart.0 */
+ &__clk_0_25, /* mcfuart.1 */
+ &__clk_0_26, /* mcfuart.2 */
+ &__clk_0_28, /* mcftmr.0 */
+ &__clk_0_29, /* mcftmr.1 */
+ &__clk_0_30, /* mcftmr.2 */
+ &__clk_0_31, /* mcftmr.3 */
+
+ &__clk_0_32, /* mcfpit.0 */
+ &__clk_0_33, /* mcfpit.1 */
+ &__clk_0_34, /* mcfpit.2 */
+ &__clk_0_35, /* mcfpit.3 */
+ &__clk_0_36, /* mcfpwm.0 */
+ &__clk_0_37, /* mcfeport.0 */
+ &__clk_0_38, /* mcfwdt.0 */
+ &__clk_0_40, /* sys.0 */
+ &__clk_0_41, /* gpio.0 */
+ &__clk_0_42, /* mcfrtc.0 */
+ &__clk_0_43, /* mcflcd.0 */
+ &__clk_0_44, /* mcfusb-otg.0 */
+ &__clk_0_45, /* mcfusb-host.0 */
+ &__clk_0_46, /* sdram.0 */
+ &__clk_0_47, /* ssi.0 */
+ &__clk_0_48, /* pll.0 */
+
+ &__clk_1_32, /* mdha.0 */
+ &__clk_1_33, /* skha.0 */
+ &__clk_1_34, /* rng.0 */
+ NULL,
+};
+
+static struct clk * const enable_clks[] __initconst = {
+ &__clk_0_2, /* flexbus */
+ &__clk_0_18, /* intc.0 */
+ &__clk_0_19, /* intc.1 */
+ &__clk_0_21, /* iack.0 */
+ &__clk_0_24, /* mcfuart.0 */
+ &__clk_0_25, /* mcfuart.1 */
+ &__clk_0_26, /* mcfuart.2 */
+ &__clk_0_28, /* mcftmr.0 */
+ &__clk_0_29, /* mcftmr.1 */
+ &__clk_0_32, /* mcfpit.0 */
+ &__clk_0_33, /* mcfpit.1 */
+ &__clk_0_37, /* mcfeport.0 */
+ &__clk_0_40, /* sys.0 */
+ &__clk_0_41, /* gpio.0 */
+ &__clk_0_46, /* sdram.0 */
+ &__clk_0_48, /* pll.0 */
+};
+
+static struct clk * const disable_clks[] __initconst = {
+ &__clk_0_8, /* mcfcan.0 */
+ &__clk_0_12, /* fec.0 */
+ &__clk_0_17, /* edma */
+ &__clk_0_22, /* imx1-i2c.0 */
+ &__clk_0_23, /* mcfqspi.0 */
+ &__clk_0_30, /* mcftmr.2 */
+ &__clk_0_31, /* mcftmr.3 */
+ &__clk_0_34, /* mcfpit.2 */
+ &__clk_0_35, /* mcfpit.3 */
+ &__clk_0_36, /* mcfpwm.0 */
+ &__clk_0_38, /* mcfwdt.0 */
+ &__clk_0_42, /* mcfrtc.0 */
+ &__clk_0_43, /* mcflcd.0 */
+ &__clk_0_44, /* mcfusb-otg.0 */
+ &__clk_0_45, /* mcfusb-host.0 */
+ &__clk_0_47, /* ssi.0 */
+ &__clk_1_32, /* mdha.0 */
+ &__clk_1_33, /* skha.0 */
+ &__clk_1_34, /* rng.0 */
+};
+
+
+static void __init m53xx_clk_init(void)
+{
+ unsigned i;
+
+ /* make sure these clocks are enabled */
+ for (i = 0; i < ARRAY_SIZE(enable_clks); ++i)
+ __clk_init_enabled(enable_clks[i]);
+ /* make sure these clocks are disabled */
+ for (i = 0; i < ARRAY_SIZE(disable_clks); ++i)
+ __clk_init_disabled(disable_clks[i]);
+}
+
+/***************************************************************************/
+
+static void __init m53xx_qspi_init(void)
+{
+#if IS_ENABLED(CONFIG_SPI_COLDFIRE_QSPI)
+ /* setup QSPS pins for QSPI with gpio CS control */
+ writew(0x01f0, MCFGPIO_PAR_QSPI);
+#endif /* IS_ENABLED(CONFIG_SPI_COLDFIRE_QSPI) */
+}
+
+/***************************************************************************/
+
+static void __init m53xx_i2c_init(void)
+{
+#if IS_ENABLED(CONFIG_I2C_IMX)
+ /* setup Port AS Pin Assignment Register for I2C */
+ /* set PASPA0 to SCL and PASPA1 to SDA */
+ u8 r = readb(MCFGPIO_PAR_FECI2C);
+ r |= 0x0f;
+ writeb(r, MCFGPIO_PAR_FECI2C);
+#endif /* IS_ENABLED(CONFIG_I2C_IMX) */
+}
+
+/***************************************************************************/
+
+static void __init m53xx_uarts_init(void)
+{
+ /* UART GPIO initialization */
+ writew(readw(MCFGPIO_PAR_UART) | 0x0FFF, MCFGPIO_PAR_UART);
+}
+
+/***************************************************************************/
+
+static void __init m53xx_fec_init(void)
+{
+ u8 v;
+
+ /* Set multi-function pins to ethernet mode for fec0 */
+ v = readb(MCFGPIO_PAR_FECI2C);
+ v |= MCF_GPIO_PAR_FECI2C_PAR_MDC_EMDC |
+ MCF_GPIO_PAR_FECI2C_PAR_MDIO_EMDIO;
+ writeb(v, MCFGPIO_PAR_FECI2C);
+
+ v = readb(MCFGPIO_PAR_FEC);
+ v = MCF_GPIO_PAR_FEC_PAR_FEC_7W_FEC | MCF_GPIO_PAR_FEC_PAR_FEC_MII_FEC;
+ writeb(v, MCFGPIO_PAR_FEC);
+}
+
+/***************************************************************************/
+
+void __init config_BSP(char *commandp, int size)
+{
+#if !defined(CONFIG_BOOTPARAM)
+ /* Copy command line from FLASH to local buffer... */
+ memcpy(commandp, (char *) 0x4000, 4);
+ if(strncmp(commandp, "kcl ", 4) == 0){
+ memcpy(commandp, (char *) 0x4004, size);
+ commandp[size-1] = 0;
+ } else {
+ memset(commandp, 0, size);
+ }
+#endif
+ mach_sched_init = hw_timer_init;
+ m53xx_clk_init();
+ m53xx_uarts_init();
+ m53xx_fec_init();
+ m53xx_qspi_init();
+ m53xx_i2c_init();
+
+#ifdef CONFIG_BDM_DISABLE
+ /*
+ * Disable the BDM clocking. This also turns off most of the rest of
+ * the BDM device. This is good for EMC reasons. This option is not
+ * incompatible with the memory protection option.
+ */
+ wdebug(MCFDEBUG_CSR, MCFDEBUG_CSR_PSTCLK);
+#endif
+}
+
+/***************************************************************************/
+/* Board initialization */
+/***************************************************************************/
+/*
+ * PLL min/max specifications
+ */
+#define MAX_FVCO 500000 /* KHz */
+#define MAX_FSYS 80000 /* KHz */
+#define MIN_FSYS 58333 /* KHz */
+#define FREF 16000 /* KHz */
+
+
+#define MAX_MFD 135 /* Multiplier */
+#define MIN_MFD 88 /* Multiplier */
+#define BUSDIV 6 /* Divider */
+
+/*
+ * Low Power Divider specifications
+ */
+#define MIN_LPD (1 << 0) /* Divider (not encoded) */
+#define MAX_LPD (1 << 15) /* Divider (not encoded) */
+#define DEFAULT_LPD (1 << 1) /* Divider (not encoded) */
+
+#define SYS_CLK_KHZ 80000
+#define SYSTEM_PERIOD 12.5
+/*
+ * SDRAM Timing Parameters
+ */
+#define SDRAM_BL 8 /* # of beats in a burst */
+#define SDRAM_TWR 2 /* in clocks */
+#define SDRAM_CASL 2.5 /* CASL in clocks */
+#define SDRAM_TRCD 2 /* in clocks */
+#define SDRAM_TRP 2 /* in clocks */
+#define SDRAM_TRFC 7 /* in clocks */
+#define SDRAM_TREFI 7800 /* in ns */
+
+#define EXT_SRAM_ADDRESS (0xC0000000)
+#define FLASH_ADDRESS (0x00000000)
+#define SDRAM_ADDRESS (0x40000000)
+
+#define NAND_FLASH_ADDRESS (0xD0000000)
+
+void wtm_init(void);
+void scm_init(void);
+void gpio_init(void);
+void fbcs_init(void);
+void sdramc_init(void);
+int clock_pll (int fsys, int flags);
+int clock_limp (int);
+int clock_exit_limp (void);
+int get_sys_clock (void);
+
+asmlinkage void __init sysinit(void)
+{
+ clock_pll(0, 0);
+
+ wtm_init();
+ scm_init();
+ gpio_init();
+ fbcs_init();
+ sdramc_init();
+}
+
+void wtm_init(void)
+{
+ /* Disable watchdog timer */
+ writew(0, MCF_WTM_WCR);
+}
+
+#define MCF_SCM_BCR_GBW (0x00000100)
+#define MCF_SCM_BCR_GBR (0x00000200)
+
+void scm_init(void)
+{
+ /* All masters are trusted */
+ writel(0x77777777, MCF_SCM_MPR);
+
+ /* Allow supervisor/user, read/write, and trusted/untrusted
+ access to all slaves */
+ writel(0, MCF_SCM_PACRA);
+ writel(0, MCF_SCM_PACRB);
+ writel(0, MCF_SCM_PACRC);
+ writel(0, MCF_SCM_PACRD);
+ writel(0, MCF_SCM_PACRE);
+ writel(0, MCF_SCM_PACRF);
+
+ /* Enable bursts */
+ writel(MCF_SCM_BCR_GBR | MCF_SCM_BCR_GBW, MCF_SCM_BCR);
+}
+
+
+void fbcs_init(void)
+{
+ writeb(0x3E, MCFGPIO_PAR_CS);
+
+ /* Latch chip select */
+ writel(0x10080000, MCF_FBCS1_CSAR);
+
+ writel(0x002A3780, MCF_FBCS1_CSCR);
+ writel(MCF_FBCS_CSMR_BAM_2M | MCF_FBCS_CSMR_V, MCF_FBCS1_CSMR);
+
+ /* Initialize latch to drive signals to inactive states */
+ writew(0xffff, 0x10080000);
+
+ /* External SRAM */
+ writel(EXT_SRAM_ADDRESS, MCF_FBCS1_CSAR);
+ writel(MCF_FBCS_CSCR_PS_16 |
+ MCF_FBCS_CSCR_AA |
+ MCF_FBCS_CSCR_SBM |
+ MCF_FBCS_CSCR_WS(1),
+ MCF_FBCS1_CSCR);
+ writel(MCF_FBCS_CSMR_BAM_512K | MCF_FBCS_CSMR_V, MCF_FBCS1_CSMR);
+
+ /* Boot Flash connected to FBCS0 */
+ writel(FLASH_ADDRESS, MCF_FBCS0_CSAR);
+ writel(MCF_FBCS_CSCR_PS_16 |
+ MCF_FBCS_CSCR_BEM |
+ MCF_FBCS_CSCR_AA |
+ MCF_FBCS_CSCR_SBM |
+ MCF_FBCS_CSCR_WS(7),
+ MCF_FBCS0_CSCR);
+ writel(MCF_FBCS_CSMR_BAM_32M | MCF_FBCS_CSMR_V, MCF_FBCS0_CSMR);
+}
+
+void sdramc_init(void)
+{
+ /*
+ * Check to see if the SDRAM has already been initialized
+ * by a run control tool
+ */
+ if (!(readl(MCF_SDRAMC_SDCR) & MCF_SDRAMC_SDCR_REF)) {
+ /* SDRAM chip select initialization */
+
+ /* Initialize SDRAM chip select */
+ writel(MCF_SDRAMC_SDCS_BA(SDRAM_ADDRESS) |
+ MCF_SDRAMC_SDCS_CSSZ(MCF_SDRAMC_SDCS_CSSZ_32MBYTE),
+ MCF_SDRAMC_SDCS0);
+
+ /*
+ * Basic configuration and initialization
+ */
+ writel(MCF_SDRAMC_SDCFG1_SRD2RW((int)((SDRAM_CASL + 2) + 0.5)) |
+ MCF_SDRAMC_SDCFG1_SWT2RD(SDRAM_TWR + 1) |
+ MCF_SDRAMC_SDCFG1_RDLAT((int)((SDRAM_CASL * 2) + 2)) |
+ MCF_SDRAMC_SDCFG1_ACT2RW((int)(SDRAM_TRCD + 0.5)) |
+ MCF_SDRAMC_SDCFG1_PRE2ACT((int)(SDRAM_TRP + 0.5)) |
+ MCF_SDRAMC_SDCFG1_REF2ACT((int)(SDRAM_TRFC + 0.5)) |
+ MCF_SDRAMC_SDCFG1_WTLAT(3),
+ MCF_SDRAMC_SDCFG1);
+ writel(MCF_SDRAMC_SDCFG2_BRD2PRE(SDRAM_BL / 2 + 1) |
+ MCF_SDRAMC_SDCFG2_BWT2RW(SDRAM_BL / 2 + SDRAM_TWR) |
+ MCF_SDRAMC_SDCFG2_BRD2WT((int)((SDRAM_CASL + SDRAM_BL / 2 - 1.0) + 0.5)) |
+ MCF_SDRAMC_SDCFG2_BL(SDRAM_BL - 1),
+ MCF_SDRAMC_SDCFG2);
+
+
+ /*
+ * Precharge and enable write to SDMR
+ */
+ writel(MCF_SDRAMC_SDCR_MODE_EN |
+ MCF_SDRAMC_SDCR_CKE |
+ MCF_SDRAMC_SDCR_DDR |
+ MCF_SDRAMC_SDCR_MUX(1) |
+ MCF_SDRAMC_SDCR_RCNT((int)(((SDRAM_TREFI / (SYSTEM_PERIOD * 64)) - 1) + 0.5)) |
+ MCF_SDRAMC_SDCR_PS_16 |
+ MCF_SDRAMC_SDCR_IPALL,
+ MCF_SDRAMC_SDCR);
+
+ /*
+ * Write extended mode register
+ */
+ writel(MCF_SDRAMC_SDMR_BNKAD_LEMR |
+ MCF_SDRAMC_SDMR_AD(0x0) |
+ MCF_SDRAMC_SDMR_CMD,
+ MCF_SDRAMC_SDMR);
+
+ /*
+ * Write mode register and reset DLL
+ */
+ writel(MCF_SDRAMC_SDMR_BNKAD_LMR |
+ MCF_SDRAMC_SDMR_AD(0x163) |
+ MCF_SDRAMC_SDMR_CMD,
+ MCF_SDRAMC_SDMR);
+
+ /*
+ * Execute a PALL command
+ */
+ writel(readl(MCF_SDRAMC_SDCR) | MCF_SDRAMC_SDCR_IPALL, MCF_SDRAMC_SDCR);
+
+ /*
+ * Perform two REF cycles
+ */
+ writel(readl(MCF_SDRAMC_SDCR) | MCF_SDRAMC_SDCR_IREF, MCF_SDRAMC_SDCR);
+ writel(readl(MCF_SDRAMC_SDCR) | MCF_SDRAMC_SDCR_IREF, MCF_SDRAMC_SDCR);
+
+ /*
+ * Write mode register and clear reset DLL
+ */
+ 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);
+}