cpu/arm926ejs/kirkwood/cpu.c - github/trini/u-boot - Gitiles

 /*
  * (C) Copyright 2009
  * Marvell Semiconductor <www.marvell.com>
  * Written-by: Prafulla Wadaskar <prafulla@marvell.com>
  *
  * See file CREDITS for list of people who contributed to this
  * project.
  *
  * 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 <netdev.h>
 #include <asm/cache.h>
 #include <u-boot/md5.h>
 #include <asm/arch/kirkwood.h>

 #define BUFLEN	16

 void reset_cpu(unsigned long ignored)
 {
 	struct kwcpu_registers *cpureg =
 	    (struct kwcpu_registers *)KW_CPU_REG_BASE;

 	writel(readl(&cpureg->rstoutn_mask) | (1 << 2),
 		&cpureg->rstoutn_mask);
 	writel(readl(&cpureg->sys_soft_rst) | 1,
 		&cpureg->sys_soft_rst);
 	while (1) ;
 }

 /*
  * Generates Ramdom hex number reading some time varient system registers
  * and using md5 algorithm
  */
 unsigned char get_random_hex(void)
 {
 	int i;
 	u32 inbuf[BUFLEN];
 	u8 outbuf[BUFLEN];

 	/*
 	 * in case of 88F6281/88F6192 A0,
 	 * Bit7 need to reset to generate random values in KW_REG_UNDOC_0x1470
 	 * Soc reg offsets KW_REG_UNDOC_0x1470 and KW_REG_UNDOC_0x1478 are reserved regs and
 	 * Does not have names at this moment (no errata available)
 	 */
 	writel(readl(KW_REG_UNDOC_0x1478) & ~(1 << 7), KW_REG_UNDOC_0x1478);
 	for (i = 0; i < BUFLEN; i++) {
 		inbuf[i] = readl(KW_REG_UNDOC_0x1470);
 	}
 	md5((u8 *) inbuf, (BUFLEN * sizeof(u32)), outbuf);
 	return outbuf[outbuf[7] % 0x0f];
 }

 /*
  * Window Size
  * Used with the Base register to set the address window size and location.
  * Must be programmed from LSB to MSB as sequence of ones followed by
  * sequence of zeros. The number of ones specifies the size of the window in
  * 64 KByte granularity (e.g., a value of 0x00FF specifies 256 = 16 MByte).
  * NOTE: A value of 0x0 specifies 64-KByte size.
  */
 unsigned int kw_winctrl_calcsize(unsigned int sizeval)
 {
 	int i;
 	unsigned int j = 0;
 	u32 val = sizeval >> 1;

 	for (i = 0; val > 0x10000; i++) {
 		j |= (1 << i);
 		val = val >> 1;
 	}
 	return (0x0000ffff & j);
 }

 /*
  * kw_config_adr_windows - Configure address Windows
  *
  * There are 8 address windows supported by Kirkwood Soc to addess different
  * devices. Each window can be configured for size, BAR and remap addr
  * Below configuration is standard for most of the cases
  *
  * If remap function not used, remap_lo must be set as base
  *
  * Reference Documentation:
  * Mbus-L to Mbus Bridge Registers Configuration.
  * (Sec 25.1 and 25.3 of Datasheet)
  */
 int kw_config_adr_windows(void)
 {
 	struct kwwin_registers *winregs =
 		(struct kwwin_registers *)KW_CPU_WIN_BASE;

 	/* Window 0: PCIE MEM address space */
 	writel(KWCPU_WIN_CTRL_DATA(1024 * 1024 * 256, KWCPU_TARGET_PCIE,
 		KWCPU_ATTR_PCIE_MEM, KWCPU_WIN_ENABLE), &winregs[0].ctrl);

 	writel(KW_DEFADR_PCI_MEM, &winregs[0].base);
 	writel(KW_DEFADR_PCI_MEM, &winregs[0].remap_lo);
 	writel(0x0, &winregs[0].remap_hi);

 	/* Window 1: PCIE IO address space */
 	writel(KWCPU_WIN_CTRL_DATA(1024 * 64, KWCPU_TARGET_PCIE,
 		KWCPU_ATTR_PCIE_IO, KWCPU_WIN_ENABLE), &winregs[1].ctrl);
 	writel(KW_DEFADR_PCI_IO, &winregs[1].base);
 	writel(KW_DEFADR_PCI_IO_REMAP, &winregs[1].remap_lo);
 	writel(0x0, &winregs[1].remap_hi);

 	/* Window 2: NAND Flash address space */
 	writel(KWCPU_WIN_CTRL_DATA(1024 * 1024 * 128, KWCPU_TARGET_MEMORY,
 		KWCPU_ATTR_NANDFLASH, KWCPU_WIN_ENABLE), &winregs[2].ctrl);
 	writel(KW_DEFADR_NANDF, &winregs[2].base);
 	writel(KW_DEFADR_NANDF, &winregs[2].remap_lo);
 	writel(0x0, &winregs[2].remap_hi);

 	/* Window 3: SPI Flash address space */
 	writel(KWCPU_WIN_CTRL_DATA(1024 * 1024 * 128, KWCPU_TARGET_MEMORY,
 		KWCPU_ATTR_SPIFLASH, KWCPU_WIN_ENABLE), &winregs[3].ctrl);
 	writel(KW_DEFADR_SPIF, &winregs[3].base);
 	writel(KW_DEFADR_SPIF, &winregs[3].remap_lo);
 	writel(0x0, &winregs[3].remap_hi);

 	/* Window 4: BOOT Memory address space */
 	writel(KWCPU_WIN_CTRL_DATA(1024 * 1024 * 128, KWCPU_TARGET_MEMORY,
 		KWCPU_ATTR_BOOTROM, KWCPU_WIN_ENABLE), &winregs[4].ctrl);
 	writel(KW_DEFADR_BOOTROM, &winregs[4].base);

 	/* Window 5: Security SRAM address space */
 	writel(KWCPU_WIN_CTRL_DATA(1024 * 64, KWCPU_TARGET_SASRAM,
 		KWCPU_ATTR_SASRAM, KWCPU_WIN_ENABLE), &winregs[5].ctrl);
 	writel(KW_DEFADR_SASRAM, &winregs[5].base);

 	/* Window 6-7: Disabled */
 	writel(KWCPU_WIN_DISABLE, &winregs[6].ctrl);
 	writel(KWCPU_WIN_DISABLE, &winregs[7].ctrl);

 	return 0;
 }

 /*
  * kw_config_gpio - GPIO configuration
  */
 void kw_config_gpio(u32 gpp0_oe_val, u32 gpp1_oe_val, u32 gpp0_oe, u32 gpp1_oe)
 {
 	struct kwgpio_registers *gpio0reg =
 		(struct kwgpio_registers *)KW_GPIO0_BASE;
 	struct kwgpio_registers *gpio1reg =
 		(struct kwgpio_registers *)KW_GPIO1_BASE;

 	/* Init GPIOS to default values as per board requirement */
 	writel(gpp0_oe_val, &gpio0reg->dout);
 	writel(gpp1_oe_val, &gpio1reg->dout);
 	writel(gpp0_oe, &gpio0reg->oe);
 	writel(gpp1_oe, &gpio1reg->oe);
 }

 /*
  * kw_config_mpp - Multi-Purpose Pins Functionality configuration
  *
  * Each MPP can be configured to different functionality through
  * MPP control register, ref (sec 6.1 of kirkwood h/w specification)
  *
  * There are maximum 64 Multi-Pourpose Pins on Kirkwood
  * Each MPP functionality can be configuration by a 4bit value
  * of MPP control reg, the value and associated functionality depends
  * upon used SoC varient
  */
 int kw_config_mpp(u32 mpp0_7, u32 mpp8_15, u32 mpp16_23, u32 mpp24_31,
 		u32 mpp32_39, u32 mpp40_47, u32 mpp48_55)
 {
 	u32 *mppreg = (u32 *) KW_MPP_BASE;

 	/* program mpp registers */
 	writel(mpp0_7, &mppreg[0]);
 	writel(mpp8_15, &mppreg[1]);
 	writel(mpp16_23, &mppreg[2]);
 	writel(mpp24_31, &mppreg[3]);
 	writel(mpp32_39, &mppreg[4]);
 	writel(mpp40_47, &mppreg[5]);
 	writel(mpp48_55, &mppreg[6]);
 	return 0;
 }

 /*
  * SYSRSTn Duration Counter Support
  *
  * Kirkwood SoC implements a hardware-based SYSRSTn duration counter.
  * When SYSRSTn is asserted low, a SYSRSTn duration counter is running.
  * The SYSRSTn duration counter is useful for implementing a manufacturer
  * or factory reset. Upon a long reset assertion that is greater than a
  * pre-configured environment variable value for sysrstdelay,
  * The counter value is stored in the SYSRSTn Length Counter Register
  * The counter is based on the 25-MHz reference clock (40ns)
  * It is a 29-bit counter, yielding a maximum counting duration of
  * 2^29/25 MHz (21.4 seconds). When the counter reach its maximum value,
  * it remains at this value until counter reset is triggered by setting
  * bit 31 of KW_REG_SYSRST_CNT
  */
 static void kw_sysrst_action(void)
 {
 	int ret;
 	char *s = getenv("sysrstcmd");

 	if (!s) {
 		debug("Error.. %s failed, check sysrstcmd\n",
 			__FUNCTION__);
 		return;
 	}

 	debug("Starting %s process...\n", __FUNCTION__);
 #if !defined(CONFIG_SYS_HUSH_PARSER)
 	ret = run_command (s, 0);
 #else
 	ret = parse_string_outer(s, FLAG_PARSE_SEMICOLON
 				  | FLAG_EXIT_FROM_LOOP);
 #endif
 	if (ret < 0)
 		debug("Error.. %s failed\n", __FUNCTION__);
 	else
 		debug("%s process finished\n", __FUNCTION__);
 }

 static void kw_sysrst_check(void)
 {
 	u32 sysrst_cnt, sysrst_dly;
 	char *s;

 	/*
 	 * no action if sysrstdelay environment variable is not defined
 	 */
 	s = getenv("sysrstdelay");
 	if (s == NULL)
 		return;

 	/* read sysrstdelay value */
 	sysrst_dly = (u32) simple_strtoul(s, NULL, 10);

 	/* read SysRst Length counter register (bits 28:0) */
 	sysrst_cnt = (0x1fffffff & readl(KW_REG_SYSRST_CNT));
 	debug("H/w Rst hold time: %d.%d secs\n",
 		sysrst_cnt / SYSRST_CNT_1SEC_VAL,
 		sysrst_cnt % SYSRST_CNT_1SEC_VAL);

 	/* clear the counter for next valid read*/
 	writel(1 << 31, KW_REG_SYSRST_CNT);

 	/*
 	 * sysrst_action:
 	 * if H/w Reset key is pressed and hold for time
 	 * more than sysrst_dly in seconds
 	 */
 	if (sysrst_cnt >= SYSRST_CNT_1SEC_VAL * sysrst_dly)
 		kw_sysrst_action();
 }

 #if defined(CONFIG_DISPLAY_CPUINFO)
 int print_cpuinfo(void)
 {
 	char *name = "Unknown";

 	switch (readl(KW_REG_DEVICE_ID) & 0x03) {
 	case 1:
 		name = "88F6192_A0";
 		break;
 	case 2:
 		name = "88F6281_A0";
 		break;
 	default:
 		printf("SoC:   Unsupported Kirkwood\n");
 		return -1;
 	}
 	printf("SoC:   Kirkwood %s\n", name);
 	return 0;
 }
 #endif /* CONFIG_DISPLAY_CPUINFO */

 #ifdef CONFIG_ARCH_CPU_INIT
 int arch_cpu_init(void)
 {
 	u32 reg;
 	struct kwcpu_registers *cpureg =
 		(struct kwcpu_registers *)KW_CPU_REG_BASE;

 	/* Linux expects` the internal registers to be at 0xf1000000 */
 	writel(KW_REGS_PHY_BASE, KW_OFFSET_REG);

 	/* Enable and invalidate L2 cache in write through mode */
 	writel(readl(&cpureg->l2_cfg) | 0x18, &cpureg->l2_cfg);
 	invalidate_l2_cache();

 	kw_config_adr_windows();

 #ifdef CONFIG_KIRKWOOD_RGMII_PAD_1V8
 	/*
 	 * Configures the I/O voltage of the pads connected to Egigabit
 	 * Ethernet interface to 1.8V
 	 * By defult it is set to 3.3V
 	 */
 	reg = readl(KW_REG_MPP_OUT_DRV_REG);
 	reg |= (1 << 7);
 	writel(reg, KW_REG_MPP_OUT_DRV_REG);
 #endif
 #ifdef CONFIG_KIRKWOOD_EGIGA_INIT
 	/*
 	 * Set egiga port0/1 in normal functional mode
 	 * This is required becasue on kirkwood by default ports are in reset mode
 	 * OS egiga driver may not have provision to set them in normal mode
 	 * and if u-boot is build without network support, network may fail at OS level
 	 */
 	reg = readl(KWGBE_PORT_SERIAL_CONTROL1_REG(0));
 	reg &= ~(1 << 4);	/* Clear PortReset Bit */
 	writel(reg, (KWGBE_PORT_SERIAL_CONTROL1_REG(0)));
 	reg = readl(KWGBE_PORT_SERIAL_CONTROL1_REG(1));
 	reg &= ~(1 << 4);	/* Clear PortReset Bit */
 	writel(reg, (KWGBE_PORT_SERIAL_CONTROL1_REG(1)));
 #endif
 #ifdef CONFIG_KIRKWOOD_PCIE_INIT
 	/*
 	 * Enable PCI Express Port0
 	 */
 	reg = readl(&cpureg->ctrl_stat);
 	reg |= (1 << 0);	/* Set PEX0En Bit */
 	writel(reg, &cpureg->ctrl_stat);
 #endif
 	return 0;
 }
 #endif /* CONFIG_ARCH_CPU_INIT */

 /*
  * SOC specific misc init
  */
 #if defined(CONFIG_ARCH_MISC_INIT)
 int arch_misc_init(void)
 {
 	volatile u32 temp;

 	/*CPU streaming & write allocate */
 	temp = readfr_extra_feature_reg();
 	temp &= ~(1 << 28);	/* disable wr alloc */
 	writefr_extra_feature_reg(temp);

 	temp = readfr_extra_feature_reg();
 	temp &= ~(1 << 29);	/* streaming disabled */
 	writefr_extra_feature_reg(temp);

 	/* L2Cache settings */
 	temp = readfr_extra_feature_reg();
 	/* Disable L2C pre fetch - Set bit 24 */
 	temp |= (1 << 24);
 	/* enable L2C - Set bit 22 */
 	temp |= (1 << 22);
 	writefr_extra_feature_reg(temp);

 	icache_enable();
 	/* Change reset vector to address 0x0 */
 	temp = get_cr();
 	set_cr(temp & ~CR_V);

 	/* checks and execute resset to factory event */
 	kw_sysrst_check();

 	return 0;
 }
 #endif /* CONFIG_ARCH_MISC_INIT */

 #ifdef CONFIG_KIRKWOOD_EGIGA
 int cpu_eth_init(bd_t *bis)
 {
 	kirkwood_egiga_initialize(bis);
 	return 0;
 }
 #endif
	/*
	* (C) Copyright 2009
	* Marvell Semiconductor <www.marvell.com>
	* Written-by: Prafulla Wadaskar <prafulla@marvell.com>
	*
	* See file CREDITS for list of people who contributed to this
	* project.
	*
	* 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 <netdev.h>
	#include <asm/cache.h>
	#include <u-boot/md5.h>
	#include <asm/arch/kirkwood.h>

	#define BUFLEN 16

	void reset_cpu(unsigned long ignored)
	{
	struct kwcpu_registers *cpureg =
	(struct kwcpu_registers *)KW_CPU_REG_BASE;

	writel(readl(&cpureg->rstoutn_mask) \| (1 << 2),
	&cpureg->rstoutn_mask);
	writel(readl(&cpureg->sys_soft_rst) \| 1,
	&cpureg->sys_soft_rst);
	while (1) ;
	}

	/*
	* Generates Ramdom hex number reading some time varient system registers
	* and using md5 algorithm
	*/
	unsigned char get_random_hex(void)
	{
	int i;
	u32 inbuf[BUFLEN];
	u8 outbuf[BUFLEN];

	/*
	* in case of 88F6281/88F6192 A0,
	* Bit7 need to reset to generate random values in KW_REG_UNDOC_0x1470
	* Soc reg offsets KW_REG_UNDOC_0x1470 and KW_REG_UNDOC_0x1478 are reserved regs and
	* Does not have names at this moment (no errata available)
	*/
	writel(readl(KW_REG_UNDOC_0x1478) & ~(1 << 7), KW_REG_UNDOC_0x1478);
	for (i = 0; i < BUFLEN; i++) {
	inbuf[i] = readl(KW_REG_UNDOC_0x1470);
	}
	md5((u8 ) inbuf, (BUFLEN sizeof(u32)), outbuf);
	return outbuf[outbuf[7] % 0x0f];
	}

	/*
	* Window Size
	* Used with the Base register to set the address window size and location.
	* Must be programmed from LSB to MSB as sequence of ones followed by
	* sequence of zeros. The number of ones specifies the size of the window in
	* 64 KByte granularity (e.g., a value of 0x00FF specifies 256 = 16 MByte).
	* NOTE: A value of 0x0 specifies 64-KByte size.
	*/
	unsigned int kw_winctrl_calcsize(unsigned int sizeval)
	{
	int i;
	unsigned int j = 0;
	u32 val = sizeval >> 1;

	for (i = 0; val > 0x10000; i++) {
	j \|= (1 << i);
	val = val >> 1;
	}
	return (0x0000ffff & j);
	}

	/*
	* kw_config_adr_windows - Configure address Windows
	*
	* There are 8 address windows supported by Kirkwood Soc to addess different
	* devices. Each window can be configured for size, BAR and remap addr
	* Below configuration is standard for most of the cases
	*
	* If remap function not used, remap_lo must be set as base
	*
	* Reference Documentation:
	* Mbus-L to Mbus Bridge Registers Configuration.
	* (Sec 25.1 and 25.3 of Datasheet)
	*/
	int kw_config_adr_windows(void)
	{
	struct kwwin_registers *winregs =
	(struct kwwin_registers *)KW_CPU_WIN_BASE;

	/* Window 0: PCIE MEM address space */
	writel(KWCPU_WIN_CTRL_DATA(1024 * 1024 * 256, KWCPU_TARGET_PCIE,
	KWCPU_ATTR_PCIE_MEM, KWCPU_WIN_ENABLE), &winregs[0].ctrl);

	writel(KW_DEFADR_PCI_MEM, &winregs[0].base);
	writel(KW_DEFADR_PCI_MEM, &winregs[0].remap_lo);
	writel(0x0, &winregs[0].remap_hi);

	/* Window 1: PCIE IO address space */
	writel(KWCPU_WIN_CTRL_DATA(1024 * 64, KWCPU_TARGET_PCIE,
	KWCPU_ATTR_PCIE_IO, KWCPU_WIN_ENABLE), &winregs[1].ctrl);
	writel(KW_DEFADR_PCI_IO, &winregs[1].base);
	writel(KW_DEFADR_PCI_IO_REMAP, &winregs[1].remap_lo);
	writel(0x0, &winregs[1].remap_hi);

	/* Window 2: NAND Flash address space */
	writel(KWCPU_WIN_CTRL_DATA(1024 * 1024 * 128, KWCPU_TARGET_MEMORY,
	KWCPU_ATTR_NANDFLASH, KWCPU_WIN_ENABLE), &winregs[2].ctrl);
	writel(KW_DEFADR_NANDF, &winregs[2].base);
	writel(KW_DEFADR_NANDF, &winregs[2].remap_lo);
	writel(0x0, &winregs[2].remap_hi);

	/* Window 3: SPI Flash address space */
	writel(KWCPU_WIN_CTRL_DATA(1024 * 1024 * 128, KWCPU_TARGET_MEMORY,
	KWCPU_ATTR_SPIFLASH, KWCPU_WIN_ENABLE), &winregs[3].ctrl);
	writel(KW_DEFADR_SPIF, &winregs[3].base);
	writel(KW_DEFADR_SPIF, &winregs[3].remap_lo);
	writel(0x0, &winregs[3].remap_hi);

	/* Window 4: BOOT Memory address space */
	writel(KWCPU_WIN_CTRL_DATA(1024 * 1024 * 128, KWCPU_TARGET_MEMORY,
	KWCPU_ATTR_BOOTROM, KWCPU_WIN_ENABLE), &winregs[4].ctrl);
	writel(KW_DEFADR_BOOTROM, &winregs[4].base);

	/* Window 5: Security SRAM address space */
	writel(KWCPU_WIN_CTRL_DATA(1024 * 64, KWCPU_TARGET_SASRAM,
	KWCPU_ATTR_SASRAM, KWCPU_WIN_ENABLE), &winregs[5].ctrl);
	writel(KW_DEFADR_SASRAM, &winregs[5].base);

	/* Window 6-7: Disabled */
	writel(KWCPU_WIN_DISABLE, &winregs[6].ctrl);
	writel(KWCPU_WIN_DISABLE, &winregs[7].ctrl);

	return 0;
	}

	/*
	* kw_config_gpio - GPIO configuration
	*/
	void kw_config_gpio(u32 gpp0_oe_val, u32 gpp1_oe_val, u32 gpp0_oe, u32 gpp1_oe)
	{
	struct kwgpio_registers *gpio0reg =
	(struct kwgpio_registers *)KW_GPIO0_BASE;
	struct kwgpio_registers *gpio1reg =
	(struct kwgpio_registers *)KW_GPIO1_BASE;

	/* Init GPIOS to default values as per board requirement */
	writel(gpp0_oe_val, &gpio0reg->dout);
	writel(gpp1_oe_val, &gpio1reg->dout);
	writel(gpp0_oe, &gpio0reg->oe);
	writel(gpp1_oe, &gpio1reg->oe);
	}

	/*
	* kw_config_mpp - Multi-Purpose Pins Functionality configuration
	*
	* Each MPP can be configured to different functionality through
	* MPP control register, ref (sec 6.1 of kirkwood h/w specification)
	*
	* There are maximum 64 Multi-Pourpose Pins on Kirkwood
	* Each MPP functionality can be configuration by a 4bit value
	* of MPP control reg, the value and associated functionality depends
	* upon used SoC varient
	*/
	int kw_config_mpp(u32 mpp0_7, u32 mpp8_15, u32 mpp16_23, u32 mpp24_31,
	u32 mpp32_39, u32 mpp40_47, u32 mpp48_55)
	{
	u32 mppreg = (u32 ) KW_MPP_BASE;

	/* program mpp registers */
	writel(mpp0_7, &mppreg[0]);
	writel(mpp8_15, &mppreg[1]);
	writel(mpp16_23, &mppreg[2]);
	writel(mpp24_31, &mppreg[3]);
	writel(mpp32_39, &mppreg[4]);
	writel(mpp40_47, &mppreg[5]);
	writel(mpp48_55, &mppreg[6]);
	return 0;
	}

	/*
	* SYSRSTn Duration Counter Support
	*
	* Kirkwood SoC implements a hardware-based SYSRSTn duration counter.
	* When SYSRSTn is asserted low, a SYSRSTn duration counter is running.
	* The SYSRSTn duration counter is useful for implementing a manufacturer
	* or factory reset. Upon a long reset assertion that is greater than a
	* pre-configured environment variable value for sysrstdelay,
	* The counter value is stored in the SYSRSTn Length Counter Register
	* The counter is based on the 25-MHz reference clock (40ns)
	* It is a 29-bit counter, yielding a maximum counting duration of
	* 2^29/25 MHz (21.4 seconds). When the counter reach its maximum value,
	* it remains at this value until counter reset is triggered by setting
	* bit 31 of KW_REG_SYSRST_CNT
	*/
	static void kw_sysrst_action(void)
	{
	int ret;
	char *s = getenv("sysrstcmd");

	if (!s) {
	debug("Error.. %s failed, check sysrstcmd\n",
	__FUNCTION__);
	return;
	}

	debug("Starting %s process...\n", __FUNCTION__);
	#if !defined(CONFIG_SYS_HUSH_PARSER)
	ret = run_command (s, 0);
	#else
	ret = parse_string_outer(s, FLAG_PARSE_SEMICOLON
	\| FLAG_EXIT_FROM_LOOP);
	#endif
	if (ret < 0)
	debug("Error.. %s failed\n", __FUNCTION__);
	else
	debug("%s process finished\n", __FUNCTION__);
	}

	static void kw_sysrst_check(void)
	{
	u32 sysrst_cnt, sysrst_dly;
	char *s;

	/*
	* no action if sysrstdelay environment variable is not defined
	*/
	s = getenv("sysrstdelay");
	if (s == NULL)
	return;

	/* read sysrstdelay value */
	sysrst_dly = (u32) simple_strtoul(s, NULL, 10);

	/* read SysRst Length counter register (bits 28:0) */
	sysrst_cnt = (0x1fffffff & readl(KW_REG_SYSRST_CNT));
	debug("H/w Rst hold time: %d.%d secs\n",
	sysrst_cnt / SYSRST_CNT_1SEC_VAL,
	sysrst_cnt % SYSRST_CNT_1SEC_VAL);

	/* clear the counter for next valid read*/
	writel(1 << 31, KW_REG_SYSRST_CNT);

	/*
	* sysrst_action:
	* if H/w Reset key is pressed and hold for time
	* more than sysrst_dly in seconds
	*/
	if (sysrst_cnt >= SYSRST_CNT_1SEC_VAL * sysrst_dly)
	kw_sysrst_action();
	}

	#if defined(CONFIG_DISPLAY_CPUINFO)
	int print_cpuinfo(void)
	{
	char *name = "Unknown";

	switch (readl(KW_REG_DEVICE_ID) & 0x03) {
	case 1:
	name = "88F6192_A0";
	break;
	case 2:
	name = "88F6281_A0";
	break;
	default:
	printf("SoC: Unsupported Kirkwood\n");
	return -1;
	}
	printf("SoC: Kirkwood %s\n", name);
	return 0;
	}
	#endif /* CONFIG_DISPLAY_CPUINFO */

	#ifdef CONFIG_ARCH_CPU_INIT
	int arch_cpu_init(void)
	{
	u32 reg;
	struct kwcpu_registers *cpureg =
	(struct kwcpu_registers *)KW_CPU_REG_BASE;

	/* Linux expects` the internal registers to be at 0xf1000000 */
	writel(KW_REGS_PHY_BASE, KW_OFFSET_REG);

	/* Enable and invalidate L2 cache in write through mode */
	writel(readl(&cpureg->l2_cfg) \| 0x18, &cpureg->l2_cfg);
	invalidate_l2_cache();

	kw_config_adr_windows();

	#ifdef CONFIG_KIRKWOOD_RGMII_PAD_1V8
	/*
	* Configures the I/O voltage of the pads connected to Egigabit
	* Ethernet interface to 1.8V
	* By defult it is set to 3.3V
	*/
	reg = readl(KW_REG_MPP_OUT_DRV_REG);
	reg \|= (1 << 7);
	writel(reg, KW_REG_MPP_OUT_DRV_REG);
	#endif
	#ifdef CONFIG_KIRKWOOD_EGIGA_INIT
	/*
	* Set egiga port0/1 in normal functional mode
	* This is required becasue on kirkwood by default ports are in reset mode
	* OS egiga driver may not have provision to set them in normal mode
	* and if u-boot is build without network support, network may fail at OS level
	*/
	reg = readl(KWGBE_PORT_SERIAL_CONTROL1_REG(0));
	reg &= ~(1 << 4); /* Clear PortReset Bit */
	writel(reg, (KWGBE_PORT_SERIAL_CONTROL1_REG(0)));
	reg = readl(KWGBE_PORT_SERIAL_CONTROL1_REG(1));
	reg &= ~(1 << 4); /* Clear PortReset Bit */
	writel(reg, (KWGBE_PORT_SERIAL_CONTROL1_REG(1)));
	#endif
	#ifdef CONFIG_KIRKWOOD_PCIE_INIT
	/*
	* Enable PCI Express Port0
	*/
	reg = readl(&cpureg->ctrl_stat);
	reg \|= (1 << 0); /* Set PEX0En Bit */
	writel(reg, &cpureg->ctrl_stat);
	#endif
	return 0;
	}
	#endif /* CONFIG_ARCH_CPU_INIT */

	/*
	* SOC specific misc init
	*/
	#if defined(CONFIG_ARCH_MISC_INIT)
	int arch_misc_init(void)
	{
	volatile u32 temp;

	/CPU streaming & write allocate /
	temp = readfr_extra_feature_reg();
	temp &= ~(1 << 28); /* disable wr alloc */
	writefr_extra_feature_reg(temp);

	temp = readfr_extra_feature_reg();
	temp &= ~(1 << 29); /* streaming disabled */
	writefr_extra_feature_reg(temp);

	/* L2Cache settings */
	temp = readfr_extra_feature_reg();
	/* Disable L2C pre fetch - Set bit 24 */
	temp \|= (1 << 24);
	/* enable L2C - Set bit 22 */
	temp \|= (1 << 22);
	writefr_extra_feature_reg(temp);

	icache_enable();
	/* Change reset vector to address 0x0 */
	temp = get_cr();
	set_cr(temp & ~CR_V);

	/* checks and execute resset to factory event */
	kw_sysrst_check();

	return 0;
	}
	#endif /* CONFIG_ARCH_MISC_INIT */

	#ifdef CONFIG_KIRKWOOD_EGIGA
	int cpu_eth_init(bd_t *bis)
	{
	kirkwood_egiga_initialize(bis);
	return 0;
	}
	#endif