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-rw-r--r--arch/arm/mach-ep93xx/core.c442
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diff --git a/arch/arm/mach-ep93xx/core.c b/arch/arm/mach-ep93xx/core.c
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+/*
+ * arch/arm/mach-ep93xx/core.c
+ * Core routines for Cirrus EP93xx chips.
+ *
+ * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
+ *
+ * Thanks go to Michael Burian and Ray Lehtiniemi for their key
+ * role in the ep93xx linux community.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/serial.h>
+#include <linux/tty.h>
+#include <linux/bitops.h>
+#include <linux/serial.h>
+#include <linux/serial_8250.h>
+#include <linux/serial_core.h>
+#include <linux/device.h>
+#include <linux/mm.h>
+#include <linux/time.h>
+#include <linux/timex.h>
+#include <linux/delay.h>
+#include <linux/termios.h>
+#include <linux/amba/bus.h>
+#include <linux/amba/serial.h>
+
+#include <asm/types.h>
+#include <asm/setup.h>
+#include <asm/memory.h>
+#include <asm/hardware.h>
+#include <asm/irq.h>
+#include <asm/system.h>
+#include <asm/tlbflush.h>
+#include <asm/pgtable.h>
+#include <asm/io.h>
+
+#include <asm/mach/map.h>
+#include <asm/mach/time.h>
+#include <asm/mach/irq.h>
+#include <asm/arch/gpio.h>
+
+#include <asm/hardware/vic.h>
+
+
+/*************************************************************************
+ * Static I/O mappings that are needed for all EP93xx platforms
+ *************************************************************************/
+static struct map_desc ep93xx_io_desc[] __initdata = {
+ {
+ .virtual = EP93XX_AHB_VIRT_BASE,
+ .pfn = __phys_to_pfn(EP93XX_AHB_PHYS_BASE),
+ .length = EP93XX_AHB_SIZE,
+ .type = MT_DEVICE,
+ }, {
+ .virtual = EP93XX_APB_VIRT_BASE,
+ .pfn = __phys_to_pfn(EP93XX_APB_PHYS_BASE),
+ .length = EP93XX_APB_SIZE,
+ .type = MT_DEVICE,
+ },
+};
+
+void __init ep93xx_map_io(void)
+{
+ iotable_init(ep93xx_io_desc, ARRAY_SIZE(ep93xx_io_desc));
+}
+
+
+/*************************************************************************
+ * Timer handling for EP93xx
+ *************************************************************************
+ * The ep93xx has four internal timers. Timers 1, 2 (both 16 bit) and
+ * 3 (32 bit) count down at 508 kHz, are self-reloading, and can generate
+ * an interrupt on underflow. Timer 4 (40 bit) counts down at 983.04 kHz,
+ * is free-running, and can't generate interrupts.
+ *
+ * The 508 kHz timers are ideal for use for the timer interrupt, as the
+ * most common values of HZ divide 508 kHz nicely. We pick one of the 16
+ * bit timers (timer 1) since we don't need more than 16 bits of reload
+ * value as long as HZ >= 8.
+ *
+ * The higher clock rate of timer 4 makes it a better choice than the
+ * other timers for use in gettimeoffset(), while the fact that it can't
+ * generate interrupts means we don't have to worry about not being able
+ * to use this timer for something else. We also use timer 4 for keeping
+ * track of lost jiffies.
+ */
+static unsigned int last_jiffy_time;
+
+#define TIMER4_TICKS_PER_JIFFY ((CLOCK_TICK_RATE + (HZ/2)) / HZ)
+
+static int ep93xx_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+ write_seqlock(&xtime_lock);
+
+ __raw_writel(1, EP93XX_TIMER1_CLEAR);
+ while (__raw_readl(EP93XX_TIMER4_VALUE_LOW) - last_jiffy_time
+ >= TIMER4_TICKS_PER_JIFFY) {
+ last_jiffy_time += TIMER4_TICKS_PER_JIFFY;
+ timer_tick(regs);
+ }
+
+ write_sequnlock(&xtime_lock);
+
+ return IRQ_HANDLED;
+}
+
+static struct irqaction ep93xx_timer_irq = {
+ .name = "ep93xx timer",
+ .flags = SA_INTERRUPT | SA_TIMER,
+ .handler = ep93xx_timer_interrupt,
+};
+
+static void __init ep93xx_timer_init(void)
+{
+ /* Enable periodic HZ timer. */
+ __raw_writel(0x48, EP93XX_TIMER1_CONTROL);
+ __raw_writel((508000 / HZ) - 1, EP93XX_TIMER1_LOAD);
+ __raw_writel(0xc8, EP93XX_TIMER1_CONTROL);
+
+ /* Enable lost jiffy timer. */
+ __raw_writel(0x100, EP93XX_TIMER4_VALUE_HIGH);
+
+ setup_irq(IRQ_EP93XX_TIMER1, &ep93xx_timer_irq);
+}
+
+static unsigned long ep93xx_gettimeoffset(void)
+{
+ int offset;
+
+ offset = __raw_readl(EP93XX_TIMER4_VALUE_LOW) - last_jiffy_time;
+
+ /* Calculate (1000000 / 983040) * offset. */
+ return offset + (53 * offset / 3072);
+}
+
+struct sys_timer ep93xx_timer = {
+ .init = ep93xx_timer_init,
+ .offset = ep93xx_gettimeoffset,
+};
+
+
+/*************************************************************************
+ * GPIO handling for EP93xx
+ *************************************************************************/
+static unsigned char gpio_int_enable[2];
+static unsigned char gpio_int_type1[2];
+static unsigned char gpio_int_type2[2];
+
+static void update_gpio_ab_int_params(int port)
+{
+ if (port == 0) {
+ __raw_writeb(0, EP93XX_GPIO_A_INT_ENABLE);
+ __raw_writeb(gpio_int_type2[0], EP93XX_GPIO_A_INT_TYPE2);
+ __raw_writeb(gpio_int_type1[0], EP93XX_GPIO_A_INT_TYPE1);
+ __raw_writeb(gpio_int_enable[0], EP93XX_GPIO_A_INT_ENABLE);
+ } else if (port == 1) {
+ __raw_writeb(0, EP93XX_GPIO_B_INT_ENABLE);
+ __raw_writeb(gpio_int_type2[1], EP93XX_GPIO_B_INT_TYPE2);
+ __raw_writeb(gpio_int_type1[1], EP93XX_GPIO_B_INT_TYPE1);
+ __raw_writeb(gpio_int_enable[1], EP93XX_GPIO_B_INT_ENABLE);
+ }
+}
+
+
+static unsigned char data_register_offset[8] = {
+ 0x00, 0x04, 0x08, 0x0c, 0x20, 0x30, 0x38, 0x40,
+};
+
+static unsigned char data_direction_register_offset[8] = {
+ 0x10, 0x14, 0x18, 0x1c, 0x24, 0x34, 0x3c, 0x44,
+};
+
+void gpio_line_config(int line, int direction)
+{
+ unsigned int data_direction_register;
+ unsigned long flags;
+ unsigned char v;
+
+ data_direction_register =
+ EP93XX_GPIO_REG(data_direction_register_offset[line >> 3]);
+
+ local_irq_save(flags);
+ if (direction == GPIO_OUT) {
+ if (line >= 0 && line < 16) {
+ gpio_int_enable[line >> 3] &= ~(1 << (line & 7));
+ update_gpio_ab_int_params(line >> 3);
+ }
+
+ v = __raw_readb(data_direction_register);
+ v |= 1 << (line & 7);
+ __raw_writeb(v, data_direction_register);
+ } else if (direction == GPIO_IN) {
+ v = __raw_readb(data_direction_register);
+ v &= ~(1 << (line & 7));
+ __raw_writeb(v, data_direction_register);
+ }
+ local_irq_restore(flags);
+}
+EXPORT_SYMBOL(gpio_line_config);
+
+int gpio_line_get(int line)
+{
+ unsigned int data_register;
+
+ data_register = EP93XX_GPIO_REG(data_register_offset[line >> 3]);
+
+ return !!(__raw_readb(data_register) & (1 << (line & 7)));
+}
+EXPORT_SYMBOL(gpio_line_get);
+
+void gpio_line_set(int line, int value)
+{
+ unsigned int data_register;
+ unsigned long flags;
+ unsigned char v;
+
+ data_register = EP93XX_GPIO_REG(data_register_offset[line >> 3]);
+
+ local_irq_save(flags);
+ if (value == EP93XX_GPIO_HIGH) {
+ v = __raw_readb(data_register);
+ v |= 1 << (line & 7);
+ __raw_writeb(v, data_register);
+ } else if (value == EP93XX_GPIO_LOW) {
+ v = __raw_readb(data_register);
+ v &= ~(1 << (line & 7));
+ __raw_writeb(v, data_register);
+ }
+ local_irq_restore(flags);
+}
+EXPORT_SYMBOL(gpio_line_set);
+
+
+/*************************************************************************
+ * EP93xx IRQ handling
+ *************************************************************************/
+static void ep93xx_gpio_ab_irq_handler(unsigned int irq,
+ struct irqdesc *desc, struct pt_regs *regs)
+{
+ unsigned char status;
+ int i;
+
+ status = __raw_readb(EP93XX_GPIO_A_INT_STATUS);
+ for (i = 0; i < 8; i++) {
+ if (status & (1 << i)) {
+ desc = irq_desc + IRQ_EP93XX_GPIO(0) + i;
+ desc_handle_irq(IRQ_EP93XX_GPIO(0) + i, desc, regs);
+ }
+ }
+
+ status = __raw_readb(EP93XX_GPIO_B_INT_STATUS);
+ for (i = 0; i < 8; i++) {
+ if (status & (1 << i)) {
+ desc = irq_desc + IRQ_EP93XX_GPIO(8) + i;
+ desc_handle_irq(IRQ_EP93XX_GPIO(8) + i, desc, regs);
+ }
+ }
+}
+
+static void ep93xx_gpio_ab_irq_mask_ack(unsigned int irq)
+{
+ int line = irq - IRQ_EP93XX_GPIO(0);
+ int port = line >> 3;
+
+ gpio_int_enable[port] &= ~(1 << (line & 7));
+ update_gpio_ab_int_params(port);
+
+ if (line >> 3) {
+ __raw_writel(1 << (line & 7), EP93XX_GPIO_B_INT_ACK);
+ } else {
+ __raw_writel(1 << (line & 7), EP93XX_GPIO_A_INT_ACK);
+ }
+}
+
+static void ep93xx_gpio_ab_irq_mask(unsigned int irq)
+{
+ int line = irq - IRQ_EP93XX_GPIO(0);
+ int port = line >> 3;
+
+ gpio_int_enable[port] &= ~(1 << (line & 7));
+ update_gpio_ab_int_params(port);
+}
+
+static void ep93xx_gpio_ab_irq_unmask(unsigned int irq)
+{
+ int line = irq - IRQ_EP93XX_GPIO(0);
+ int port = line >> 3;
+
+ gpio_int_enable[port] |= 1 << (line & 7);
+ update_gpio_ab_int_params(port);
+}
+
+
+/*
+ * gpio_int_type1 controls whether the interrupt is level (0) or
+ * edge (1) triggered, while gpio_int_type2 controls whether it
+ * triggers on low/falling (0) or high/rising (1).
+ */
+static int ep93xx_gpio_ab_irq_type(unsigned int irq, unsigned int type)
+{
+ int port;
+ int line;
+
+ line = irq - IRQ_EP93XX_GPIO(0);
+ gpio_line_config(line, GPIO_IN);
+
+ port = line >> 3;
+ line &= 7;
+
+ if (type & IRQT_RISING) {
+ gpio_int_type1[port] |= 1 << line;
+ gpio_int_type2[port] |= 1 << line;
+ } else if (type & IRQT_FALLING) {
+ gpio_int_type1[port] |= 1 << line;
+ gpio_int_type2[port] &= ~(1 << line);
+ } else if (type & IRQT_HIGH) {
+ gpio_int_type1[port] &= ~(1 << line);
+ gpio_int_type2[port] |= 1 << line;
+ } else if (type & IRQT_LOW) {
+ gpio_int_type1[port] &= ~(1 << line);
+ gpio_int_type2[port] &= ~(1 << line);
+ }
+ update_gpio_ab_int_params(port);
+
+ return 0;
+}
+
+static struct irqchip ep93xx_gpio_ab_irq_chip = {
+ .ack = ep93xx_gpio_ab_irq_mask_ack,
+ .mask = ep93xx_gpio_ab_irq_mask,
+ .unmask = ep93xx_gpio_ab_irq_unmask,
+ .set_type = ep93xx_gpio_ab_irq_type,
+};
+
+
+void __init ep93xx_init_irq(void)
+{
+ int irq;
+
+ vic_init((void *)EP93XX_VIC1_BASE, 0, EP93XX_VIC1_VALID_IRQ_MASK);
+ vic_init((void *)EP93XX_VIC2_BASE, 32, EP93XX_VIC2_VALID_IRQ_MASK);
+
+ for (irq = IRQ_EP93XX_GPIO(0) ; irq <= IRQ_EP93XX_GPIO(15); irq++) {
+ set_irq_chip(irq, &ep93xx_gpio_ab_irq_chip);
+ set_irq_handler(irq, do_level_IRQ);
+ set_irq_flags(irq, IRQF_VALID);
+ }
+ set_irq_chained_handler(IRQ_EP93XX_GPIO_AB, ep93xx_gpio_ab_irq_handler);
+}
+
+
+/*************************************************************************
+ * EP93xx peripheral handling
+ *************************************************************************/
+#define EP93XX_UART_MCR_OFFSET (0x0100)
+
+static void ep93xx_uart_set_mctrl(struct amba_device *dev,
+ void __iomem *base, unsigned int mctrl)
+{
+ unsigned int mcr;
+
+ mcr = 0;
+ if (!(mctrl & TIOCM_RTS))
+ mcr |= 2;
+ if (!(mctrl & TIOCM_DTR))
+ mcr |= 1;
+
+ __raw_writel(mcr, base + EP93XX_UART_MCR_OFFSET);
+}
+
+static struct amba_pl010_data ep93xx_uart_data = {
+ .set_mctrl = ep93xx_uart_set_mctrl,
+};
+
+static struct amba_device uart1_device = {
+ .dev = {
+ .bus_id = "apb:uart1",
+ .platform_data = &ep93xx_uart_data,
+ },
+ .res = {
+ .start = EP93XX_UART1_PHYS_BASE,
+ .end = EP93XX_UART1_PHYS_BASE + 0x0fff,
+ .flags = IORESOURCE_MEM,
+ },
+ .irq = { IRQ_EP93XX_UART1, NO_IRQ },
+ .periphid = 0x00041010,
+};
+
+static struct amba_device uart2_device = {
+ .dev = {
+ .bus_id = "apb:uart2",
+ .platform_data = &ep93xx_uart_data,
+ },
+ .res = {
+ .start = EP93XX_UART2_PHYS_BASE,
+ .end = EP93XX_UART2_PHYS_BASE + 0x0fff,
+ .flags = IORESOURCE_MEM,
+ },
+ .irq = { IRQ_EP93XX_UART2, NO_IRQ },
+ .periphid = 0x00041010,
+};
+
+static struct amba_device uart3_device = {
+ .dev = {
+ .bus_id = "apb:uart3",
+ .platform_data = &ep93xx_uart_data,
+ },
+ .res = {
+ .start = EP93XX_UART3_PHYS_BASE,
+ .end = EP93XX_UART3_PHYS_BASE + 0x0fff,
+ .flags = IORESOURCE_MEM,
+ },
+ .irq = { IRQ_EP93XX_UART3, NO_IRQ },
+ .periphid = 0x00041010,
+};
+
+void __init ep93xx_init_devices(void)
+{
+ unsigned int v;
+
+ /*
+ * Disallow access to MaverickCrunch initially.
+ */
+ v = __raw_readl(EP93XX_SYSCON_DEVICE_CONFIG);
+ v &= ~EP93XX_SYSCON_DEVICE_CONFIG_CRUNCH_ENABLE;
+ __raw_writel(0xaa, EP93XX_SYSCON_SWLOCK);
+ __raw_writel(v, EP93XX_SYSCON_DEVICE_CONFIG);
+
+ amba_device_register(&uart1_device, &iomem_resource);
+ amba_device_register(&uart2_device, &iomem_resource);
+ amba_device_register(&uart3_device, &iomem_resource);
+}