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-rw-r--r--arch/arm/mach-ebsa110/core.c245
1 files changed, 245 insertions, 0 deletions
diff --git a/arch/arm/mach-ebsa110/core.c b/arch/arm/mach-ebsa110/core.c
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+++ b/arch/arm/mach-ebsa110/core.c
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+/*
+ * 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