diff options
Diffstat (limited to 'arch/arm/mach-ebsa110/core.c')
| -rw-r--r-- | arch/arm/mach-ebsa110/core.c | 245 |
1 files changed, 245 insertions, 0 deletions
diff --git a/arch/arm/mach-ebsa110/core.c b/arch/arm/mach-ebsa110/core.c new file mode 100644 index 000000000000..ef362d44949d --- /dev/null +++ b/arch/arm/mach-ebsa110/core.c @@ -0,0 +1,245 @@ +/* + * 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 <asm/hardware.h> +#include <asm/irq.h> +#include <asm/io.h> +#include <asm/setup.h> +#include <asm/mach-types.h> +#include <asm/pgtable.h> +#include <asm/page.h> +#include <asm/system.h> + +#include <asm/mach/arch.h> +#include <asm/mach/irq.h> +#include <asm/mach/map.h> + +#include <asm/mach/time.h> + +#define IRQ_MASK 0xfe000000 /* read */ +#define IRQ_MSET 0xfe000000 /* write */ +#define IRQ_STAT 0xff000000 /* read */ +#define IRQ_MCLR 0xff000000 /* write */ + +static void ebsa110_mask_irq(unsigned int irq) +{ + __raw_writeb(1 << irq, IRQ_MCLR); +} + +static void ebsa110_unmask_irq(unsigned int irq) +{ + __raw_writeb(1 << irq, IRQ_MSET); +} + +static struct irqchip ebsa110_irq_chip = { + .ack = ebsa110_mask_irq, + .mask = ebsa110_mask_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++) { + set_irq_chip(irq, &ebsa110_irq_chip); + set_irq_handler(irq, do_level_IRQ); + set_irq_flags(irq, IRQF_VALID | IRQF_PROBE); + } +} + +static struct map_desc ebsa110_io_desc[] __initdata = { + /* + * sparse external-decode ISAIO space + */ + { IRQ_STAT, TRICK4_PHYS, PGDIR_SIZE, MT_DEVICE }, /* IRQ_STAT/IRQ_MCLR */ + { IRQ_MASK, TRICK3_PHYS, PGDIR_SIZE, MT_DEVICE }, /* IRQ_MASK/IRQ_MSET */ + { SOFT_BASE, TRICK1_PHYS, PGDIR_SIZE, MT_DEVICE }, /* SOFT_BASE */ + { PIT_BASE, TRICK0_PHYS, PGDIR_SIZE, MT_DEVICE }, /* PIT_BASE */ + + /* + * self-decode ISAIO space + */ + { ISAIO_BASE, ISAIO_PHYS, ISAIO_SIZE, MT_DEVICE }, + { ISAMEM_BASE, ISAMEM_PHYS, ISAMEM_SIZE, MT_DEVICE } +}; + +static void __init ebsa110_map_io(void) +{ + iotable_init(ebsa110_io_desc, ARRAY_SIZE(ebsa110_io_desc)); +} + + +#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 unsigned long 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; +} + +static irqreturn_t +ebsa110_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs) +{ + u32 count; + + write_seqlock(&xtime_lock); + + /* 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(regs); + + write_sequnlock(&xtime_lock); + + return IRQ_HANDLED; +} + +static struct irqaction ebsa110_timer_irq = { + .name = "EBSA110 Timer Tick", + .flags = SA_INTERRUPT, + .handler = ebsa110_timer_interrupt +}; + +/* + * Set up timer interrupt. + */ +static void __init ebsa110_timer_init(void) +{ + /* + * 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 sys_timer ebsa110_timer = { + .init = ebsa110_timer_init, + .offset = ebsa110_gettimeoffset, +}; + +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 = 0, + .dev = { + .platform_data = serial_platform_data, + }, +}; + +static int __init ebsa110_init(void) +{ + return platform_device_register(&serial_device); +} + +arch_initcall(ebsa110_init); + +MACHINE_START(EBSA110, "EBSA110") + MAINTAINER("Russell King") + BOOT_MEM(0x00000000, 0xe0000000, 0xe0000000) + BOOT_PARAMS(0x00000400) + DISABLE_PARPORT(0) + DISABLE_PARPORT(2) + SOFT_REBOOT + MAPIO(ebsa110_map_io) + INITIRQ(ebsa110_init_irq) + .timer = &ebsa110_timer, +MACHINE_END |