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Diffstat (limited to 'arch/arm/mach-ep93xx/core.c')
| -rw-r--r-- | arch/arm/mach-ep93xx/core.c | 374 |
1 files changed, 374 insertions, 0 deletions
diff --git a/arch/arm/mach-ep93xx/core.c b/arch/arm/mach-ep93xx/core.c new file mode 100644 index 000000000000..865427bfad7e --- /dev/null +++ b/arch/arm/mach-ep93xx/core.c @@ -0,0 +1,374 @@ +/* + * 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/amba/bus.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 + *************************************************************************/ +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); +} |
