arch/arm/mach-ebsa110/core.c - linux - Git at Google

 /*
  *  linux/arch/arm/mach-ebsa110/core.c
  *
  *  Copyright (C) 1998-2001 Russell King
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  *
  *  Extra MM routines for the EBSA-110 architecture
  */
 #include <linux/kernel.h>
 #include <linux/mm.h>
 #include <linux/interrupt.h>
 #include <linux/serial_8250.h>
 #include <linux/init.h>
 #include <linux/io.h>

 #include <mach/hardware.h>
 #include <asm/irq.h>
 #include <asm/setup.h>
 #include <asm/mach-types.h>
 #include <asm/pgtable.h>
 #include <asm/page.h>
 #include <asm/system_misc.h>

 #include <asm/mach/arch.h>
 #include <asm/mach/irq.h>
 #include <asm/mach/map.h>

 #include <asm/mach/time.h>

 #include "core.h"

 static void ebsa110_mask_irq(struct irq_data *d)
 {
 	__raw_writeb(1 << d->irq, IRQ_MCLR);
 }

 static void ebsa110_unmask_irq(struct irq_data *d)
 {
 	__raw_writeb(1 << d->irq, IRQ_MSET);
 }

 static struct irq_chip ebsa110_irq_chip = {
 	.irq_ack	= ebsa110_mask_irq,
 	.irq_mask	= ebsa110_mask_irq,
 	.irq_unmask	= ebsa110_unmask_irq,
 };

 static void __init ebsa110_init_irq(void)
 {
 	unsigned long flags;
 	unsigned int irq;

 	local_irq_save(flags);
 	__raw_writeb(0xff, IRQ_MCLR);
 	__raw_writeb(0x55, IRQ_MSET);
 	__raw_writeb(0x00, IRQ_MSET);
 	if (__raw_readb(IRQ_MASK) != 0x55)
 		while (1);
 	__raw_writeb(0xff, IRQ_MCLR);	/* clear all interrupt enables */
 	local_irq_restore(flags);

 	for (irq = 0; irq < NR_IRQS; irq++) {
 		irq_set_chip_and_handler(irq, &ebsa110_irq_chip,
 					 handle_level_irq);
 		irq_clear_status_flags(irq, IRQ_NOREQUEST | IRQ_NOPROBE);
 	}
 }

 static struct map_desc ebsa110_io_desc[] __initdata = {
 	/*
 	 * sparse external-decode ISAIO space
 	 */
 	{	/* IRQ_STAT/IRQ_MCLR */
 		.virtual	= (unsigned long)IRQ_STAT,
 		.pfn		= __phys_to_pfn(TRICK4_PHYS),
 		.length		= TRICK4_SIZE,
 		.type		= MT_DEVICE
 	}, {	/* IRQ_MASK/IRQ_MSET */
 		.virtual	= (unsigned long)IRQ_MASK,
 		.pfn		= __phys_to_pfn(TRICK3_PHYS),
 		.length		= TRICK3_SIZE,
 		.type		= MT_DEVICE
 	}, {	/* SOFT_BASE */
 		.virtual	= (unsigned long)SOFT_BASE,
 		.pfn		= __phys_to_pfn(TRICK1_PHYS),
 		.length		= TRICK1_SIZE,
 		.type		= MT_DEVICE
 	}, {	/* PIT_BASE */
 		.virtual	= (unsigned long)PIT_BASE,
 		.pfn		= __phys_to_pfn(TRICK0_PHYS),
 		.length		= TRICK0_SIZE,
 		.type		= MT_DEVICE
 	},

 	/*
 	 * self-decode ISAIO space
 	 */
 	{
 		.virtual	= ISAIO_BASE,
 		.pfn		= __phys_to_pfn(ISAIO_PHYS),
 		.length		= ISAIO_SIZE,
 		.type		= MT_DEVICE
 	}, {
 		.virtual	= ISAMEM_BASE,
 		.pfn		= __phys_to_pfn(ISAMEM_PHYS),
 		.length		= ISAMEM_SIZE,
 		.type		= MT_DEVICE
 	}
 };

 static void __init ebsa110_map_io(void)
 {
 	iotable_init(ebsa110_io_desc, ARRAY_SIZE(ebsa110_io_desc));
 }

 static void __iomem *ebsa110_ioremap_caller(phys_addr_t cookie, size_t size,
 					    unsigned int flags, void *caller)
 {
 	return (void __iomem *)cookie;
 }

 static void ebsa110_iounmap(volatile void __iomem *io_addr)
 {}

 static void __init ebsa110_init_early(void)
 {
 	arch_ioremap_caller = ebsa110_ioremap_caller;
 	arch_iounmap = ebsa110_iounmap;
 }

 #define PIT_CTRL		(PIT_BASE + 0x0d)
 #define PIT_T2			(PIT_BASE + 0x09)
 #define PIT_T1			(PIT_BASE + 0x05)
 #define PIT_T0			(PIT_BASE + 0x01)

 /*
  * This is the rate at which your MCLK signal toggles (in Hz)
  * This was measured on a 10 digit frequency counter sampling
  * over 1 second.
  */
 #define MCLK	47894000

 /*
  * This is the rate at which the PIT timers get clocked
  */
 #define CLKBY7	(MCLK / 7)

 /*
  * This is the counter value.  We tick at 200Hz on this platform.
  */
 #define COUNT	((CLKBY7 + (HZ / 2)) / HZ)

 /*
  * Get the time offset from the system PIT.  Note that if we have missed an
  * interrupt, then the PIT counter will roll over (ie, be negative).
  * This actually works out to be convenient.
  */
 static u32 ebsa110_gettimeoffset(void)
 {
 	unsigned long offset, count;

 	__raw_writeb(0x40, PIT_CTRL);
 	count = __raw_readb(PIT_T1);
 	count |= __raw_readb(PIT_T1) << 8;

 	/*
 	 * If count > COUNT, make the number negative.
 	 */
 	if (count > COUNT)
 		count |= 0xffff0000;

 	offset = COUNT;
 	offset -= count;

 	/*
 	 * `offset' is in units of timer counts.  Convert
 	 * offset to units of microseconds.
 	 */
 	offset = offset * (1000000 / HZ) / COUNT;

 	return offset * 1000;
 }

 static irqreturn_t
 ebsa110_timer_interrupt(int irq, void *dev_id)
 {
 	u32 count;

 	/* latch and read timer 1 */
 	__raw_writeb(0x40, PIT_CTRL);
 	count = __raw_readb(PIT_T1);
 	count |= __raw_readb(PIT_T1) << 8;

 	count += COUNT;

 	__raw_writeb(count & 0xff, PIT_T1);
 	__raw_writeb(count >> 8, PIT_T1);

 	timer_tick();

 	return IRQ_HANDLED;
 }

 static struct irqaction ebsa110_timer_irq = {
 	.name		= "EBSA110 Timer Tick",
 	.flags		= IRQF_TIMER | IRQF_IRQPOLL,
 	.handler	= ebsa110_timer_interrupt,
 };

 /*
  * Set up timer interrupt.
  */
 void __init ebsa110_timer_init(void)
 {
 	arch_gettimeoffset = ebsa110_gettimeoffset;

 	/*
 	 * Timer 1, mode 2, LSB/MSB
 	 */
 	__raw_writeb(0x70, PIT_CTRL);
 	__raw_writeb(COUNT & 0xff, PIT_T1);
 	__raw_writeb(COUNT >> 8, PIT_T1);

 	setup_irq(IRQ_EBSA110_TIMER0, &ebsa110_timer_irq);
 }

 static struct plat_serial8250_port serial_platform_data[] = {
 	{
 		.iobase		= 0x3f8,
 		.irq		= 1,
 		.uartclk	= 1843200,
 		.regshift	= 0,
 		.iotype		= UPIO_PORT,
 		.flags		= UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
 	},
 	{
 		.iobase		= 0x2f8,
 		.irq		= 2,
 		.uartclk	= 1843200,
 		.regshift	= 0,
 		.iotype		= UPIO_PORT,
 		.flags		= UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
 	},
 	{ },
 };

 static struct platform_device serial_device = {
 	.name			= "serial8250",
 	.id			= PLAT8250_DEV_PLATFORM,
 	.dev			= {
 		.platform_data	= serial_platform_data,
 	},
 };

 static struct resource am79c961_resources[] = {
 	{
 		.start		= 0x220,
 		.end		= 0x238,
 		.flags		= IORESOURCE_IO,
 	}, {
 		.start		= IRQ_EBSA110_ETHERNET,
 		.end		= IRQ_EBSA110_ETHERNET,
 		.flags		= IORESOURCE_IRQ,
 	},
 };

 static struct platform_device am79c961_device = {
 	.name			= "am79c961",
 	.id			= -1,
 	.num_resources		= ARRAY_SIZE(am79c961_resources),
 	.resource		= am79c961_resources,
 };

 static struct platform_device *ebsa110_devices[] = {
 	&serial_device,
 	&am79c961_device,
 };

 /*
  * EBSA110 idling methodology:
  *
  * We can not execute the "wait for interrupt" instruction since that
  * will stop our MCLK signal (which provides the clock for the glue
  * logic, and therefore the timer interrupt).
  *
  * Instead, we spin, polling the IRQ_STAT register for the occurrence
  * of any interrupt with core clock down to the memory clock.
  */
 static void ebsa110_idle(void)
 {
 	const char *irq_stat = (char *)0xff000000;

 	/* disable clock switching */
 	asm volatile ("mcr p15, 0, ip, c15, c2, 2" : : : "cc");

 	/* wait for an interrupt to occur */
 	while (!*irq_stat);

 	/* enable clock switching */
 	asm volatile ("mcr p15, 0, ip, c15, c1, 2" : : : "cc");
 }

 static int __init ebsa110_init(void)
 {
 	arm_pm_idle = ebsa110_idle;
 	return platform_add_devices(ebsa110_devices, ARRAY_SIZE(ebsa110_devices));
 }

 arch_initcall(ebsa110_init);

 static void ebsa110_restart(enum reboot_mode mode, const char *cmd)
 {
 	soft_restart(0x80000000);
 }

 MACHINE_START(EBSA110, "EBSA110")
 	/* Maintainer: Russell King */
 	.atag_offset	= 0x400,
 	.reserve_lp0	= 1,
 	.reserve_lp2	= 1,
 	.map_io		= ebsa110_map_io,
 	.init_early	= ebsa110_init_early,
 	.init_irq	= ebsa110_init_irq,
 	.init_time	= ebsa110_timer_init,
 	.restart	= ebsa110_restart,
 MACHINE_END
	/*
	* linux/arch/arm/mach-ebsa110/core.c
	*
	* Copyright (C) 1998-2001 Russell King
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*
	* Extra MM routines for the EBSA-110 architecture
	*/
	#include <linux/kernel.h>
	#include <linux/mm.h>
	#include <linux/interrupt.h>
	#include <linux/serial_8250.h>
	#include <linux/init.h>
	#include <linux/io.h>

	#include <mach/hardware.h>
	#include <asm/irq.h>
	#include <asm/setup.h>
	#include <asm/mach-types.h>
	#include <asm/pgtable.h>
	#include <asm/page.h>
	#include <asm/system_misc.h>

	#include <asm/mach/arch.h>
	#include <asm/mach/irq.h>
	#include <asm/mach/map.h>

	#include <asm/mach/time.h>

	#include "core.h"

	static void ebsa110_mask_irq(struct irq_data *d)
	{
	__raw_writeb(1 << d->irq, IRQ_MCLR);
	}

	static void ebsa110_unmask_irq(struct irq_data *d)
	{
	__raw_writeb(1 << d->irq, IRQ_MSET);
	}

	static struct irq_chip ebsa110_irq_chip = {
	.irq_ack = ebsa110_mask_irq,
	.irq_mask = ebsa110_mask_irq,
	.irq_unmask = ebsa110_unmask_irq,
	};

	static void __init ebsa110_init_irq(void)
	{
	unsigned long flags;
	unsigned int irq;

	local_irq_save(flags);
	__raw_writeb(0xff, IRQ_MCLR);
	__raw_writeb(0x55, IRQ_MSET);
	__raw_writeb(0x00, IRQ_MSET);
	if (__raw_readb(IRQ_MASK) != 0x55)
	while (1);
	__raw_writeb(0xff, IRQ_MCLR); /* clear all interrupt enables */
	local_irq_restore(flags);

	for (irq = 0; irq < NR_IRQS; irq++) {
	irq_set_chip_and_handler(irq, &ebsa110_irq_chip,
	handle_level_irq);
	irq_clear_status_flags(irq, IRQ_NOREQUEST \| IRQ_NOPROBE);
	}
	}

	static struct map_desc ebsa110_io_desc[] __initdata = {
	/*
	* sparse external-decode ISAIO space
	*/
	{ /* IRQ_STAT/IRQ_MCLR */
	.virtual = (unsigned long)IRQ_STAT,
	.pfn = __phys_to_pfn(TRICK4_PHYS),
	.length = TRICK4_SIZE,
	.type = MT_DEVICE
	}, { /* IRQ_MASK/IRQ_MSET */
	.virtual = (unsigned long)IRQ_MASK,
	.pfn = __phys_to_pfn(TRICK3_PHYS),
	.length = TRICK3_SIZE,
	.type = MT_DEVICE
	}, { /* SOFT_BASE */
	.virtual = (unsigned long)SOFT_BASE,
	.pfn = __phys_to_pfn(TRICK1_PHYS),
	.length = TRICK1_SIZE,
	.type = MT_DEVICE
	}, { /* PIT_BASE */
	.virtual = (unsigned long)PIT_BASE,
	.pfn = __phys_to_pfn(TRICK0_PHYS),
	.length = TRICK0_SIZE,
	.type = MT_DEVICE
	},

	/*
	* self-decode ISAIO space
	*/
	{
	.virtual = ISAIO_BASE,
	.pfn = __phys_to_pfn(ISAIO_PHYS),
	.length = ISAIO_SIZE,
	.type = MT_DEVICE
	}, {
	.virtual = ISAMEM_BASE,
	.pfn = __phys_to_pfn(ISAMEM_PHYS),
	.length = ISAMEM_SIZE,
	.type = MT_DEVICE
	}
	};

	static void __init ebsa110_map_io(void)
	{
	iotable_init(ebsa110_io_desc, ARRAY_SIZE(ebsa110_io_desc));
	}

	static void __iomem *ebsa110_ioremap_caller(phys_addr_t cookie, size_t size,
	unsigned int flags, void *caller)
	{
	return (void __iomem *)cookie;
	}

	static void ebsa110_iounmap(volatile void __iomem *io_addr)
	{}

	static void __init ebsa110_init_early(void)
	{
	arch_ioremap_caller = ebsa110_ioremap_caller;
	arch_iounmap = ebsa110_iounmap;
	}

	#define PIT_CTRL (PIT_BASE + 0x0d)
	#define PIT_T2 (PIT_BASE + 0x09)
	#define PIT_T1 (PIT_BASE + 0x05)
	#define PIT_T0 (PIT_BASE + 0x01)

	/*
	* This is the rate at which your MCLK signal toggles (in Hz)
	* This was measured on a 10 digit frequency counter sampling
	* over 1 second.
	*/
	#define MCLK 47894000

	/*
	* This is the rate at which the PIT timers get clocked
	*/
	#define CLKBY7 (MCLK / 7)

	/*
	* This is the counter value. We tick at 200Hz on this platform.
	*/
	#define COUNT ((CLKBY7 + (HZ / 2)) / HZ)

	/*
	* Get the time offset from the system PIT. Note that if we have missed an
	* interrupt, then the PIT counter will roll over (ie, be negative).
	* This actually works out to be convenient.
	*/
	static u32 ebsa110_gettimeoffset(void)
	{
	unsigned long offset, count;

	__raw_writeb(0x40, PIT_CTRL);
	count = __raw_readb(PIT_T1);
	count \|= __raw_readb(PIT_T1) << 8;

	/*
	* If count > COUNT, make the number negative.
	*/
	if (count > COUNT)
	count \|= 0xffff0000;

	offset = COUNT;
	offset -= count;

	/*
	* `offset' is in units of timer counts. Convert
	* offset to units of microseconds.
	*/
	offset = offset * (1000000 / HZ) / COUNT;

	return offset * 1000;
	}

	static irqreturn_t
	ebsa110_timer_interrupt(int irq, void *dev_id)
	{
	u32 count;

	/* latch and read timer 1 */
	__raw_writeb(0x40, PIT_CTRL);
	count = __raw_readb(PIT_T1);
	count \|= __raw_readb(PIT_T1) << 8;

	count += COUNT;

	__raw_writeb(count & 0xff, PIT_T1);
	__raw_writeb(count >> 8, PIT_T1);

	timer_tick();

	return IRQ_HANDLED;
	}

	static struct irqaction ebsa110_timer_irq = {
	.name = "EBSA110 Timer Tick",
	.flags = IRQF_TIMER \| IRQF_IRQPOLL,
	.handler = ebsa110_timer_interrupt,
	};

	/*
	* Set up timer interrupt.
	*/
	void __init ebsa110_timer_init(void)
	{
	arch_gettimeoffset = ebsa110_gettimeoffset;

	/*
	* Timer 1, mode 2, LSB/MSB
	*/
	__raw_writeb(0x70, PIT_CTRL);
	__raw_writeb(COUNT & 0xff, PIT_T1);
	__raw_writeb(COUNT >> 8, PIT_T1);

	setup_irq(IRQ_EBSA110_TIMER0, &ebsa110_timer_irq);
	}

	static struct plat_serial8250_port serial_platform_data[] = {
	{
	.iobase = 0x3f8,
	.irq = 1,
	.uartclk = 1843200,
	.regshift = 0,
	.iotype = UPIO_PORT,
	.flags = UPF_BOOT_AUTOCONF \| UPF_SKIP_TEST,
	},
	{
	.iobase = 0x2f8,
	.irq = 2,
	.uartclk = 1843200,
	.regshift = 0,
	.iotype = UPIO_PORT,
	.flags = UPF_BOOT_AUTOCONF \| UPF_SKIP_TEST,
	},
	{ },
	};

	static struct platform_device serial_device = {
	.name = "serial8250",
	.id = PLAT8250_DEV_PLATFORM,
	.dev = {
	.platform_data = serial_platform_data,
	},
	};

	static struct resource am79c961_resources[] = {
	{
	.start = 0x220,
	.end = 0x238,
	.flags = IORESOURCE_IO,
	}, {
	.start = IRQ_EBSA110_ETHERNET,
	.end = IRQ_EBSA110_ETHERNET,
	.flags = IORESOURCE_IRQ,
	},
	};

	static struct platform_device am79c961_device = {
	.name = "am79c961",
	.id = -1,
	.num_resources = ARRAY_SIZE(am79c961_resources),
	.resource = am79c961_resources,
	};

	static struct platform_device *ebsa110_devices[] = {
	&serial_device,
	&am79c961_device,
	};

	/*
	* EBSA110 idling methodology:
	*
	* We can not execute the "wait for interrupt" instruction since that
	* will stop our MCLK signal (which provides the clock for the glue
	* logic, and therefore the timer interrupt).
	*
	* Instead, we spin, polling the IRQ_STAT register for the occurrence
	* of any interrupt with core clock down to the memory clock.
	*/
	static void ebsa110_idle(void)
	{
	const char irq_stat = (char )0xff000000;

	/* disable clock switching */
	asm volatile ("mcr p15, 0, ip, c15, c2, 2" : : : "cc");

	/* wait for an interrupt to occur */
	while (!*irq_stat);

	/* enable clock switching */
	asm volatile ("mcr p15, 0, ip, c15, c1, 2" : : : "cc");
	}

	static int __init ebsa110_init(void)
	{
	arm_pm_idle = ebsa110_idle;
	return platform_add_devices(ebsa110_devices, ARRAY_SIZE(ebsa110_devices));
	}

	arch_initcall(ebsa110_init);

	static void ebsa110_restart(enum reboot_mode mode, const char *cmd)
	{
	soft_restart(0x80000000);
	}

	MACHINE_START(EBSA110, "EBSA110")
	/* Maintainer: Russell King */
	.atag_offset = 0x400,
	.reserve_lp0 = 1,
	.reserve_lp2 = 1,
	.map_io = ebsa110_map_io,
	.init_early = ebsa110_init_early,
	.init_irq = ebsa110_init_irq,
	.init_time = ebsa110_timer_init,
	.restart = ebsa110_restart,
	MACHINE_END