arch/powerpc/platforms/52xx/mpc52xx_common.c - linux/kernel/git/davem/net-next - Git at Google

 /*
  *
  * Utility functions for the Freescale MPC52xx.
  *
  * Copyright (C) 2006 Sylvain Munaut <tnt@246tNt.com>
  *
  * This file is licensed under the terms of the GNU General Public License
  * version 2. This program is licensed "as is" without any warranty of any
  * kind, whether express or implied.
  *
  */

 #undef DEBUG

 #include <linux/gpio.h>
 #include <linux/kernel.h>
 #include <linux/spinlock.h>
 #include <linux/of_platform.h>
 #include <linux/of_gpio.h>
 #include <linux/export.h>
 #include <asm/io.h>
 #include <asm/prom.h>
 #include <asm/mpc52xx.h>

 /* MPC5200 device tree match tables */
 static const struct of_device_id mpc52xx_xlb_ids[] __initconst = {
 	{ .compatible = "fsl,mpc5200-xlb", },
 	{ .compatible = "mpc5200-xlb", },
 	{}
 };
 static const struct of_device_id mpc52xx_bus_ids[] __initconst = {
 	{ .compatible = "fsl,mpc5200-immr", },
 	{ .compatible = "fsl,mpc5200b-immr", },
 	{ .compatible = "simple-bus", },

 	/* depreciated matches; shouldn't be used in new device trees */
 	{ .compatible = "fsl,lpb", },
 	{ .type = "builtin", .compatible = "mpc5200", }, /* efika */
 	{ .type = "soc", .compatible = "mpc5200", }, /* lite5200 */
 	{}
 };

 /*
  * This variable is mapped in mpc52xx_map_wdt() and used in mpc52xx_restart().
  * Permanent mapping is required because mpc52xx_restart() can be called
  * from interrupt context while node mapping (which calls ioremap())
  * cannot be used at such point.
  */
 static DEFINE_SPINLOCK(mpc52xx_lock);
 static struct mpc52xx_gpt __iomem *mpc52xx_wdt;
 static struct mpc52xx_cdm __iomem *mpc52xx_cdm;

 /*
  * Configure the XLB arbiter settings to match what Linux expects.
  */
 void __init
 mpc5200_setup_xlb_arbiter(void)
 {
 	struct device_node *np;
 	struct mpc52xx_xlb  __iomem *xlb;

 	np = of_find_matching_node(NULL, mpc52xx_xlb_ids);
 	xlb = of_iomap(np, 0);
 	of_node_put(np);
 	if (!xlb) {
 		printk(KERN_ERR __FILE__ ": "
 			"Error mapping XLB in mpc52xx_setup_cpu(). "
 			"Expect some abnormal behavior\n");
 		return;
 	}

 	/* Configure the XLB Arbiter priorities */
 	out_be32(&xlb->master_pri_enable, 0xff);
 	out_be32(&xlb->master_priority, 0x11111111);

 	/*
 	 * Disable XLB pipelining
 	 * (cfr errate 292. We could do this only just before ATA PIO
 	 *  transaction and re-enable it afterwards ...)
 	 * Not needed on MPC5200B.
 	 */
 	if ((mfspr(SPRN_SVR) & MPC5200_SVR_MASK) == MPC5200_SVR)
 		out_be32(&xlb->config, in_be32(&xlb->config) | MPC52xx_XLB_CFG_PLDIS);

 	iounmap(xlb);
 }

 /*
  * This variable is mapped in mpc52xx_map_common_devices and
  * used in mpc5200_psc_ac97_gpio_reset().
  */
 static DEFINE_SPINLOCK(gpio_lock);
 struct mpc52xx_gpio __iomem *simple_gpio;
 struct mpc52xx_gpio_wkup __iomem *wkup_gpio;

 /**
  * mpc52xx_declare_of_platform_devices: register internal devices and children
  *					of the localplus bus to the of_platform
  *					bus.
  */
 void __init mpc52xx_declare_of_platform_devices(void)
 {
 	/* Find all the 'platform' devices and register them. */
 	if (of_platform_populate(NULL, mpc52xx_bus_ids, NULL, NULL))
 		pr_err(__FILE__ ": Error while populating devices from DT\n");
 }

 /*
  * match tables used by mpc52xx_map_common_devices()
  */
 static const struct of_device_id mpc52xx_gpt_ids[] __initconst = {
 	{ .compatible = "fsl,mpc5200-gpt", },
 	{ .compatible = "mpc5200-gpt", }, /* old */
 	{}
 };
 static const struct of_device_id mpc52xx_cdm_ids[] __initconst = {
 	{ .compatible = "fsl,mpc5200-cdm", },
 	{ .compatible = "mpc5200-cdm", }, /* old */
 	{}
 };
 static const struct of_device_id mpc52xx_gpio_simple[] __initconst = {
 	{ .compatible = "fsl,mpc5200-gpio", },
 	{}
 };
 static const struct of_device_id mpc52xx_gpio_wkup[] __initconst = {
 	{ .compatible = "fsl,mpc5200-gpio-wkup", },
 	{}
 };


 /**
  * mpc52xx_map_common_devices: iomap devices required by common code
  */
 void __init
 mpc52xx_map_common_devices(void)
 {
 	struct device_node *np;

 	/* mpc52xx_wdt is mapped here and used in mpc52xx_restart,
 	 * possibly from a interrupt context. wdt is only implement
 	 * on a gpt0, so check has-wdt property before mapping.
 	 */
 	for_each_matching_node(np, mpc52xx_gpt_ids) {
 		if (of_get_property(np, "fsl,has-wdt", NULL) ||
 		    of_get_property(np, "has-wdt", NULL)) {
 			mpc52xx_wdt = of_iomap(np, 0);
 			of_node_put(np);
 			break;
 		}
 	}

 	/* Clock Distribution Module, used by PSC clock setting function */
 	np = of_find_matching_node(NULL, mpc52xx_cdm_ids);
 	mpc52xx_cdm = of_iomap(np, 0);
 	of_node_put(np);

 	/* simple_gpio registers */
 	np = of_find_matching_node(NULL, mpc52xx_gpio_simple);
 	simple_gpio = of_iomap(np, 0);
 	of_node_put(np);

 	/* wkup_gpio registers */
 	np = of_find_matching_node(NULL, mpc52xx_gpio_wkup);
 	wkup_gpio = of_iomap(np, 0);
 	of_node_put(np);
 }

 /**
  * mpc52xx_set_psc_clkdiv: Set clock divider in the CDM for PSC ports
  *
  * @psc_id: id of psc port; must be 1,2,3 or 6
  * @clkdiv: clock divider value to put into CDM PSC register.
  */
 int mpc52xx_set_psc_clkdiv(int psc_id, int clkdiv)
 {
 	unsigned long flags;
 	u16 __iomem *reg;
 	u32 val;
 	u32 mask;
 	u32 mclken_div;

 	if (!mpc52xx_cdm)
 		return -ENODEV;

 	mclken_div = 0x8000 | (clkdiv & 0x1FF);
 	switch (psc_id) {
 	case 1: reg = &mpc52xx_cdm->mclken_div_psc1; mask = 0x20; break;
 	case 2: reg = &mpc52xx_cdm->mclken_div_psc2; mask = 0x40; break;
 	case 3: reg = &mpc52xx_cdm->mclken_div_psc3; mask = 0x80; break;
 	case 6: reg = &mpc52xx_cdm->mclken_div_psc6; mask = 0x10; break;
 	default:
 		return -ENODEV;
 	}

 	/* Set the rate and enable the clock */
 	spin_lock_irqsave(&mpc52xx_lock, flags);
 	out_be16(reg, mclken_div);
 	val = in_be32(&mpc52xx_cdm->clk_enables);
 	out_be32(&mpc52xx_cdm->clk_enables, val | mask);
 	spin_unlock_irqrestore(&mpc52xx_lock, flags);

 	return 0;
 }
 EXPORT_SYMBOL(mpc52xx_set_psc_clkdiv);

 /**
  * mpc52xx_get_xtal_freq - Get SYS_XTAL_IN frequency for a device
  *
  * @node: device node
  *
  * Returns the frequency of the external oscillator clock connected
  * to the SYS_XTAL_IN pin, or 0 if it cannot be determined.
  */
 unsigned int mpc52xx_get_xtal_freq(struct device_node *node)
 {
 	u32 val;
 	unsigned int freq;

 	if (!mpc52xx_cdm)
 		return 0;

 	freq = mpc5xxx_get_bus_frequency(node);
 	if (!freq)
 		return 0;

 	if (in_8(&mpc52xx_cdm->ipb_clk_sel) & 0x1)
 		freq *= 2;

 	val  = in_be32(&mpc52xx_cdm->rstcfg);
 	if (val & (1 << 5))
 		freq *= 8;
 	else
 		freq *= 4;
 	if (val & (1 << 6))
 		freq /= 12;
 	else
 		freq /= 16;

 	return freq;
 }
 EXPORT_SYMBOL(mpc52xx_get_xtal_freq);

 /**
  * mpc52xx_restart: ppc_md->restart hook for mpc5200 using the watchdog timer
  */
 void __noreturn mpc52xx_restart(char *cmd)
 {
 	local_irq_disable();

 	/* Turn on the watchdog and wait for it to expire.
 	 * It effectively does a reset. */
 	if (mpc52xx_wdt) {
 		out_be32(&mpc52xx_wdt->mode, 0x00000000);
 		out_be32(&mpc52xx_wdt->count, 0x000000ff);
 		out_be32(&mpc52xx_wdt->mode, 0x00009004);
 	} else
 		printk(KERN_ERR __FILE__ ": "
 			"mpc52xx_restart: Can't access wdt. "
 			"Restart impossible, system halted.\n");

 	while (1);
 }

 #define PSC1_RESET     0x1
 #define PSC1_SYNC      0x4
 #define PSC1_SDATA_OUT 0x1
 #define PSC2_RESET     0x2
 #define PSC2_SYNC      (0x4<<4)
 #define PSC2_SDATA_OUT (0x1<<4)
 #define MPC52xx_GPIO_PSC1_MASK 0x7
 #define MPC52xx_GPIO_PSC2_MASK (0x7<<4)

 /**
  * mpc5200_psc_ac97_gpio_reset: Use gpio pins to reset the ac97 bus
  *
  * @psc: psc number to reset (only psc 1 and 2 support ac97)
  */
 int mpc5200_psc_ac97_gpio_reset(int psc_number)
 {
 	unsigned long flags;
 	u32 gpio;
 	u32 mux;
 	int out;
 	int reset;
 	int sync;

 	if ((!simple_gpio) || (!wkup_gpio))
 		return -ENODEV;

 	switch (psc_number) {
 	case 0:
 		reset   = PSC1_RESET;           /* AC97_1_RES */
 		sync    = PSC1_SYNC;            /* AC97_1_SYNC */
 		out     = PSC1_SDATA_OUT;       /* AC97_1_SDATA_OUT */
 		gpio    = MPC52xx_GPIO_PSC1_MASK;
 		break;
 	case 1:
 		reset   = PSC2_RESET;           /* AC97_2_RES */
 		sync    = PSC2_SYNC;            /* AC97_2_SYNC */
 		out     = PSC2_SDATA_OUT;       /* AC97_2_SDATA_OUT */
 		gpio    = MPC52xx_GPIO_PSC2_MASK;
 		break;
 	default:
 		pr_err(__FILE__ ": Unable to determine PSC, no ac97 "
 		       "cold-reset will be performed\n");
 		return -ENODEV;
 	}

 	spin_lock_irqsave(&gpio_lock, flags);

 	/* Reconfiure pin-muxing to gpio */
 	mux = in_be32(&simple_gpio->port_config);
 	out_be32(&simple_gpio->port_config, mux & (~gpio));

 	/* enable gpio pins for output */
 	setbits8(&wkup_gpio->wkup_gpioe, reset);
 	setbits32(&simple_gpio->simple_gpioe, sync | out);

 	setbits8(&wkup_gpio->wkup_ddr, reset);
 	setbits32(&simple_gpio->simple_ddr, sync | out);

 	/* Assert cold reset */
 	clrbits32(&simple_gpio->simple_dvo, sync | out);
 	clrbits8(&wkup_gpio->wkup_dvo, reset);

 	/* wait for 1 us */
 	udelay(1);

 	/* Deassert reset */
 	setbits8(&wkup_gpio->wkup_dvo, reset);

 	/* wait at least 200ns */
 	/* 7 ~= (200ns * timebase) / ns2sec */
 	__delay(7);

 	/* Restore pin-muxing */
 	out_be32(&simple_gpio->port_config, mux);

 	spin_unlock_irqrestore(&gpio_lock, flags);

 	return 0;
 }
 EXPORT_SYMBOL(mpc5200_psc_ac97_gpio_reset);
	/*
	*
	* Utility functions for the Freescale MPC52xx.
	*
	* Copyright (C) 2006 Sylvain Munaut <tnt@246tNt.com>
	*
	* This file is licensed under the terms of the GNU General Public License
	* version 2. This program is licensed "as is" without any warranty of any
	* kind, whether express or implied.
	*
	*/

	#undef DEBUG

	#include <linux/gpio.h>
	#include <linux/kernel.h>
	#include <linux/spinlock.h>
	#include <linux/of_platform.h>
	#include <linux/of_gpio.h>
	#include <linux/export.h>
	#include <asm/io.h>
	#include <asm/prom.h>
	#include <asm/mpc52xx.h>

	/* MPC5200 device tree match tables */
	static const struct of_device_id mpc52xx_xlb_ids[] __initconst = {
	{ .compatible = "fsl,mpc5200-xlb", },
	{ .compatible = "mpc5200-xlb", },
	{}
	};
	static const struct of_device_id mpc52xx_bus_ids[] __initconst = {
	{ .compatible = "fsl,mpc5200-immr", },
	{ .compatible = "fsl,mpc5200b-immr", },
	{ .compatible = "simple-bus", },

	/* depreciated matches; shouldn't be used in new device trees */
	{ .compatible = "fsl,lpb", },
	{ .type = "builtin", .compatible = "mpc5200", }, /* efika */
	{ .type = "soc", .compatible = "mpc5200", }, /* lite5200 */
	{}
	};

	/*
	* This variable is mapped in mpc52xx_map_wdt() and used in mpc52xx_restart().
	* Permanent mapping is required because mpc52xx_restart() can be called
	* from interrupt context while node mapping (which calls ioremap())
	* cannot be used at such point.
	*/
	static DEFINE_SPINLOCK(mpc52xx_lock);
	static struct mpc52xx_gpt __iomem *mpc52xx_wdt;
	static struct mpc52xx_cdm __iomem *mpc52xx_cdm;

	/*
	* Configure the XLB arbiter settings to match what Linux expects.
	*/
	void __init
	mpc5200_setup_xlb_arbiter(void)
	{
	struct device_node *np;
	struct mpc52xx_xlb __iomem *xlb;

	np = of_find_matching_node(NULL, mpc52xx_xlb_ids);
	xlb = of_iomap(np, 0);
	of_node_put(np);
	if (!xlb) {
	printk(KERN_ERR __FILE__ ": "
	"Error mapping XLB in mpc52xx_setup_cpu(). "
	"Expect some abnormal behavior\n");
	return;
	}

	/* Configure the XLB Arbiter priorities */
	out_be32(&xlb->master_pri_enable, 0xff);
	out_be32(&xlb->master_priority, 0x11111111);

	/*
	* Disable XLB pipelining
	* (cfr errate 292. We could do this only just before ATA PIO
	* transaction and re-enable it afterwards ...)
	* Not needed on MPC5200B.
	*/
	if ((mfspr(SPRN_SVR) & MPC5200_SVR_MASK) == MPC5200_SVR)
	out_be32(&xlb->config, in_be32(&xlb->config) \| MPC52xx_XLB_CFG_PLDIS);

	iounmap(xlb);
	}

	/*
	* This variable is mapped in mpc52xx_map_common_devices and
	* used in mpc5200_psc_ac97_gpio_reset().
	*/
	static DEFINE_SPINLOCK(gpio_lock);
	struct mpc52xx_gpio __iomem *simple_gpio;
	struct mpc52xx_gpio_wkup __iomem *wkup_gpio;

	/**
	* mpc52xx_declare_of_platform_devices: register internal devices and children
	* of the localplus bus to the of_platform
	* bus.
	*/
	void __init mpc52xx_declare_of_platform_devices(void)
	{
	/* Find all the 'platform' devices and register them. */
	if (of_platform_populate(NULL, mpc52xx_bus_ids, NULL, NULL))
	pr_err(__FILE__ ": Error while populating devices from DT\n");
	}

	/*
	* match tables used by mpc52xx_map_common_devices()
	*/
	static const struct of_device_id mpc52xx_gpt_ids[] __initconst = {
	{ .compatible = "fsl,mpc5200-gpt", },
	{ .compatible = "mpc5200-gpt", }, /* old */
	{}
	};
	static const struct of_device_id mpc52xx_cdm_ids[] __initconst = {
	{ .compatible = "fsl,mpc5200-cdm", },
	{ .compatible = "mpc5200-cdm", }, /* old */
	{}
	};
	static const struct of_device_id mpc52xx_gpio_simple[] __initconst = {
	{ .compatible = "fsl,mpc5200-gpio", },
	{}
	};
	static const struct of_device_id mpc52xx_gpio_wkup[] __initconst = {
	{ .compatible = "fsl,mpc5200-gpio-wkup", },
	{}
	};


	/**
	* mpc52xx_map_common_devices: iomap devices required by common code
	*/
	void __init
	mpc52xx_map_common_devices(void)
	{
	struct device_node *np;

	/* mpc52xx_wdt is mapped here and used in mpc52xx_restart,
	* possibly from a interrupt context. wdt is only implement
	* on a gpt0, so check has-wdt property before mapping.
	*/
	for_each_matching_node(np, mpc52xx_gpt_ids) {
	if (of_get_property(np, "fsl,has-wdt", NULL) \|\|
	of_get_property(np, "has-wdt", NULL)) {
	mpc52xx_wdt = of_iomap(np, 0);
	of_node_put(np);
	break;
	}
	}

	/* Clock Distribution Module, used by PSC clock setting function */
	np = of_find_matching_node(NULL, mpc52xx_cdm_ids);
	mpc52xx_cdm = of_iomap(np, 0);
	of_node_put(np);

	/* simple_gpio registers */
	np = of_find_matching_node(NULL, mpc52xx_gpio_simple);
	simple_gpio = of_iomap(np, 0);
	of_node_put(np);

	/* wkup_gpio registers */
	np = of_find_matching_node(NULL, mpc52xx_gpio_wkup);
	wkup_gpio = of_iomap(np, 0);
	of_node_put(np);
	}

	/**
	* mpc52xx_set_psc_clkdiv: Set clock divider in the CDM for PSC ports
	*
	* @psc_id: id of psc port; must be 1,2,3 or 6
	* @clkdiv: clock divider value to put into CDM PSC register.
	*/
	int mpc52xx_set_psc_clkdiv(int psc_id, int clkdiv)
	{
	unsigned long flags;
	u16 __iomem *reg;
	u32 val;
	u32 mask;
	u32 mclken_div;

	if (!mpc52xx_cdm)
	return -ENODEV;

	mclken_div = 0x8000 \| (clkdiv & 0x1FF);
	switch (psc_id) {
	case 1: reg = &mpc52xx_cdm->mclken_div_psc1; mask = 0x20; break;
	case 2: reg = &mpc52xx_cdm->mclken_div_psc2; mask = 0x40; break;
	case 3: reg = &mpc52xx_cdm->mclken_div_psc3; mask = 0x80; break;
	case 6: reg = &mpc52xx_cdm->mclken_div_psc6; mask = 0x10; break;
	default:
	return -ENODEV;
	}

	/* Set the rate and enable the clock */
	spin_lock_irqsave(&mpc52xx_lock, flags);
	out_be16(reg, mclken_div);
	val = in_be32(&mpc52xx_cdm->clk_enables);
	out_be32(&mpc52xx_cdm->clk_enables, val \| mask);
	spin_unlock_irqrestore(&mpc52xx_lock, flags);

	return 0;
	}
	EXPORT_SYMBOL(mpc52xx_set_psc_clkdiv);

	/**
	* mpc52xx_get_xtal_freq - Get SYS_XTAL_IN frequency for a device
	*
	* @node: device node
	*
	* Returns the frequency of the external oscillator clock connected
	* to the SYS_XTAL_IN pin, or 0 if it cannot be determined.
	*/
	unsigned int mpc52xx_get_xtal_freq(struct device_node *node)
	{
	u32 val;
	unsigned int freq;

	if (!mpc52xx_cdm)
	return 0;

	freq = mpc5xxx_get_bus_frequency(node);
	if (!freq)
	return 0;

	if (in_8(&mpc52xx_cdm->ipb_clk_sel) & 0x1)
	freq *= 2;

	val = in_be32(&mpc52xx_cdm->rstcfg);
	if (val & (1 << 5))
	freq *= 8;
	else
	freq *= 4;
	if (val & (1 << 6))
	freq /= 12;
	else
	freq /= 16;

	return freq;
	}
	EXPORT_SYMBOL(mpc52xx_get_xtal_freq);

	/**
	* mpc52xx_restart: ppc_md->restart hook for mpc5200 using the watchdog timer
	*/
	void __noreturn mpc52xx_restart(char *cmd)
	{
	local_irq_disable();

	/* Turn on the watchdog and wait for it to expire.
	* It effectively does a reset. */
	if (mpc52xx_wdt) {
	out_be32(&mpc52xx_wdt->mode, 0x00000000);
	out_be32(&mpc52xx_wdt->count, 0x000000ff);
	out_be32(&mpc52xx_wdt->mode, 0x00009004);
	} else
	printk(KERN_ERR __FILE__ ": "
	"mpc52xx_restart: Can't access wdt. "
	"Restart impossible, system halted.\n");

	while (1);
	}

	#define PSC1_RESET 0x1
	#define PSC1_SYNC 0x4
	#define PSC1_SDATA_OUT 0x1
	#define PSC2_RESET 0x2
	#define PSC2_SYNC (0x4<<4)
	#define PSC2_SDATA_OUT (0x1<<4)
	#define MPC52xx_GPIO_PSC1_MASK 0x7
	#define MPC52xx_GPIO_PSC2_MASK (0x7<<4)

	/**
	* mpc5200_psc_ac97_gpio_reset: Use gpio pins to reset the ac97 bus
	*
	* @psc: psc number to reset (only psc 1 and 2 support ac97)
	*/
	int mpc5200_psc_ac97_gpio_reset(int psc_number)
	{
	unsigned long flags;
	u32 gpio;
	u32 mux;
	int out;
	int reset;
	int sync;

	if ((!simple_gpio) \|\| (!wkup_gpio))
	return -ENODEV;

	switch (psc_number) {
	case 0:
	reset = PSC1_RESET; /* AC97_1_RES */
	sync = PSC1_SYNC; /* AC97_1_SYNC */
	out = PSC1_SDATA_OUT; /* AC97_1_SDATA_OUT */
	gpio = MPC52xx_GPIO_PSC1_MASK;
	break;
	case 1:
	reset = PSC2_RESET; /* AC97_2_RES */
	sync = PSC2_SYNC; /* AC97_2_SYNC */
	out = PSC2_SDATA_OUT; /* AC97_2_SDATA_OUT */
	gpio = MPC52xx_GPIO_PSC2_MASK;
	break;
	default:
	pr_err(__FILE__ ": Unable to determine PSC, no ac97 "
	"cold-reset will be performed\n");
	return -ENODEV;
	}

	spin_lock_irqsave(&gpio_lock, flags);

	/* Reconfiure pin-muxing to gpio */
	mux = in_be32(&simple_gpio->port_config);
	out_be32(&simple_gpio->port_config, mux & (~gpio));

	/* enable gpio pins for output */
	setbits8(&wkup_gpio->wkup_gpioe, reset);
	setbits32(&simple_gpio->simple_gpioe, sync \| out);

	setbits8(&wkup_gpio->wkup_ddr, reset);
	setbits32(&simple_gpio->simple_ddr, sync \| out);

	/* Assert cold reset */
	clrbits32(&simple_gpio->simple_dvo, sync \| out);
	clrbits8(&wkup_gpio->wkup_dvo, reset);

	/* wait for 1 us */
	udelay(1);

	/* Deassert reset */
	setbits8(&wkup_gpio->wkup_dvo, reset);

	/* wait at least 200ns */
	/* 7 ~= (200ns * timebase) / ns2sec */
	__delay(7);

	/* Restore pin-muxing */
	out_be32(&simple_gpio->port_config, mux);

	spin_unlock_irqrestore(&gpio_lock, flags);

	return 0;
	}
	EXPORT_SYMBOL(mpc5200_psc_ac97_gpio_reset);