--- /dev/null
+/*
+ * arch/arm/mach-ixp4xx/common.c
+ *
+ * Generic code shared across all IXP4XX platforms
+ *
+ * Maintainer: Deepak Saxena <dsaxena@plexity.net>
+ *
+ * Copyright 2002 (c) Intel Corporation
+ * Copyright 2003-2004 (c) MontaVista, Software, Inc.
+ *
+ * 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.
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/serial.h>
+#include <linux/sched.h>
+#include <linux/tty.h>
+#include <linux/serial_core.h>
+#include <linux/bootmem.h>
+#include <linux/interrupt.h>
+#include <linux/bitops.h>
+#include <linux/time.h>
+#include <linux/timex.h>
+
+#include <asm/hardware.h>
+#include <asm/uaccess.h>
+#include <asm/io.h>
+#include <asm/pgtable.h>
+#include <asm/page.h>
+#include <asm/irq.h>
+
+#include <asm/mach/map.h>
+#include <asm/mach/irq.h>
+
+
+/*************************************************************************
+ * GPIO acces functions
+ *************************************************************************/
+
+/*
+ * Configure GPIO line for input, interrupt, or output operation
+ *
+ * TODO: Enable/disable the irq_desc based on interrupt or output mode.
+ * TODO: Should these be named ixp4xx_gpio_?
+ */
+void gpio_line_config(u8 line, u32 style)
+{
+ u32 enable;
+ volatile u32 *int_reg;
+ u32 int_style;
+
+ enable = *IXP4XX_GPIO_GPOER;
+
+ if (style & IXP4XX_GPIO_OUT) {
+ enable &= ~((1) << line);
+ } else if (style & IXP4XX_GPIO_IN) {
+ enable |= ((1) << line);
+
+ switch (style & IXP4XX_GPIO_INTSTYLE_MASK)
+ {
+ case (IXP4XX_GPIO_ACTIVE_HIGH):
+ int_style = IXP4XX_GPIO_STYLE_ACTIVE_HIGH;
+ break;
+ case (IXP4XX_GPIO_ACTIVE_LOW):
+ int_style = IXP4XX_GPIO_STYLE_ACTIVE_LOW;
+ break;
+ case (IXP4XX_GPIO_RISING_EDGE):
+ int_style = IXP4XX_GPIO_STYLE_RISING_EDGE;
+ break;
+ case (IXP4XX_GPIO_FALLING_EDGE):
+ int_style = IXP4XX_GPIO_STYLE_FALLING_EDGE;
+ break;
+ case (IXP4XX_GPIO_TRANSITIONAL):
+ int_style = IXP4XX_GPIO_STYLE_TRANSITIONAL;
+ break;
+ default:
+ int_style = IXP4XX_GPIO_STYLE_ACTIVE_HIGH;
+ break;
+ }
+
+ if (line >= 8) { /* pins 8-15 */
+ line -= 8;
+ int_reg = IXP4XX_GPIO_GPIT2R;
+ }
+ else { /* pins 0-7 */
+ int_reg = IXP4XX_GPIO_GPIT1R;
+ }
+
+ /* Clear the style for the appropriate pin */
+ *int_reg &= ~(IXP4XX_GPIO_STYLE_CLEAR <<
+ (line * IXP4XX_GPIO_STYLE_SIZE));
+
+ /* Set the new style */
+ *int_reg |= (int_style << (line * IXP4XX_GPIO_STYLE_SIZE));
+ }
+
+ *IXP4XX_GPIO_GPOER = enable;
+}
+
+EXPORT_SYMBOL(gpio_line_config);
+
+/*************************************************************************
+ * IXP4xx chipset I/O mapping
+ *************************************************************************/
+static struct map_desc ixp4xx_io_desc[] __initdata = {
+ { /* UART, Interrupt ctrl, GPIO, timers, NPEs, MACs, USB .... */
+ .virtual = IXP4XX_PERIPHERAL_BASE_VIRT,
+ .physical = IXP4XX_PERIPHERAL_BASE_PHYS,
+ .length = IXP4XX_PERIPHERAL_REGION_SIZE,
+ .type = MT_DEVICE
+ }, { /* Expansion Bus Config Registers */
+ .virtual = IXP4XX_EXP_CFG_BASE_VIRT,
+ .physical = IXP4XX_EXP_CFG_BASE_PHYS,
+ .length = IXP4XX_EXP_CFG_REGION_SIZE,
+ .type = MT_DEVICE
+ }, { /* PCI Registers */
+ .virtual = IXP4XX_PCI_CFG_BASE_VIRT,
+ .physical = IXP4XX_PCI_CFG_BASE_PHYS,
+ .length = IXP4XX_PCI_CFG_REGION_SIZE,
+ .type = MT_DEVICE
+ }
+};
+
+void __init ixp4xx_map_io(void)
+{
+ iotable_init(ixp4xx_io_desc, ARRAY_SIZE(ixp4xx_io_desc));
+}
+
+
+/*************************************************************************
+ * IXP4xx chipset IRQ handling
+ *
+ * TODO: GPIO IRQs should be marked invalid until the user of the IRQ
+ * (be it PCI or something else) configures that GPIO line
+ * as an IRQ. Also, we should use a different chip structure for
+ * level-based GPIO vs edge-based GPIO. Currently nobody needs this as
+ * all HW that's publically available uses level IRQs, so we'll
+ * worry about it if/when we have HW to test.
+ **************************************************************************/
+static void ixp4xx_irq_mask(unsigned int irq)
+{
+ *IXP4XX_ICMR &= ~(1 << irq);
+}
+
+static void ixp4xx_irq_mask_ack(unsigned int irq)
+{
+ ixp4xx_irq_mask(irq);
+}
+
+static void ixp4xx_irq_unmask(unsigned int irq)
+{
+ static int irq2gpio[NR_IRQS] = {
+ -1, -1, -1, -1, -1, -1, 0, 1,
+ -1, -1, -1, -1, -1, -1, -1, -1,
+ -1, -1, -1, 2, 3, 4, 5, 6,
+ 7, 8, 9, 10, 11, 12, -1, -1,
+ };
+ int line = irq2gpio[irq];
+
+ /*
+ * This only works for LEVEL gpio IRQs as per the IXP4xx developer's
+ * manual. If edge-triggered, need to move it to the mask_ack.
+ * Nobody seems to be using the edge-triggered mode on the GPIOs.
+ */
+ if (line >= 0)
+ gpio_line_isr_clear(line);
+
+ *IXP4XX_ICMR |= (1 << irq);
+}
+
+static struct irqchip ixp4xx_irq_chip = {
+ .ack = ixp4xx_irq_mask_ack,
+ .mask = ixp4xx_irq_mask,
+ .unmask = ixp4xx_irq_unmask,
+};
+
+void __init ixp4xx_init_irq(void)
+{
+ int i = 0;
+
+ /* Route all sources to IRQ instead of FIQ */
+ *IXP4XX_ICLR = 0x0;
+
+ /* Disable all interrupt */
+ *IXP4XX_ICMR = 0x0;
+
+ for(i = 0; i < NR_IRQS; i++)
+ {
+ set_irq_chip(i, &ixp4xx_irq_chip);
+ set_irq_handler(i, do_level_IRQ);
+ set_irq_flags(i, IRQF_VALID);
+ }
+}
+
+
+/*************************************************************************
+ * IXP4xx timer tick
+ * We use OS timer1 on the CPU for the timer tick and the timestamp
+ * counter as a source of real clock ticks to account for missed jiffies.
+ *************************************************************************/
+
+static unsigned volatile last_jiffy_time;
+
+#define CLOCK_TICKS_PER_USEC (CLOCK_TICK_RATE / USEC_PER_SEC)
+
+/* IRQs are disabled before entering here from do_gettimeofday() */
+static unsigned long ixp4xx_gettimeoffset(void)
+{
+ u32 elapsed;
+
+ elapsed = *IXP4XX_OSTS - last_jiffy_time;
+
+ return elapsed / CLOCK_TICKS_PER_USEC;
+}
+
+static irqreturn_t ixp4xx_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+ /* Clear Pending Interrupt by writing '1' to it */
+ *IXP4XX_OSST = IXP4XX_OSST_TIMER_1_PEND;
+
+ /*
+ * Catch up with the real idea of time
+ */
+ do {
+ do_timer(regs);
+ last_jiffy_time += LATCH;
+ } while((*IXP4XX_OSTS - last_jiffy_time) > LATCH);
+
+ return IRQ_HANDLED;
+}
+
+extern unsigned long (*gettimeoffset)(void);
+
+static struct irqaction timer_irq = {
+ .name = "IXP4xx Timer Tick",
+ .flags = SA_INTERRUPT
+};
+
+void __init time_init(void)
+{
+ gettimeoffset = ixp4xx_gettimeoffset;
+ timer_irq.handler = ixp4xx_timer_interrupt;
+
+ /* Clear Pending Interrupt by writing '1' to it */
+ *IXP4XX_OSST = IXP4XX_OSST_TIMER_1_PEND;
+
+ /* Setup the Timer counter value */
+ *IXP4XX_OSRT1 = (LATCH & ~IXP4XX_OST_RELOAD_MASK) | IXP4XX_OST_ENABLE;
+
+ /* Reset time-stamp counter */
+ *IXP4XX_OSTS = 0;
+ last_jiffy_time = 0;
+
+ /* Connect the interrupt handler and enable the interrupt */
+ setup_irq(IRQ_IXP4XX_TIMER1, &timer_irq);
+}
+
+
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