/*
 * arch/arm/mach-ixp2000/ixdp2x00.c
 *
 * Code common to IXDP2400 and IXDP2800 platforms.
 *
 * Original Author: Naeem Afzal <naeem.m.afzal@intel.com>
 * Maintainer: Deepak Saxena <dsaxena@plexity.net>
 *
 * Copyright (C) 2002 Intel Corp.
 * Copyright (C) 2003-2004 MontaVista Software, Inc.
 *
 *  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/kernel.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/bitops.h>
#include <linux/pci.h>
#include <linux/ioport.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/io.h>

#include <asm/irq.h>
#include <asm/pgtable.h>
#include <asm/page.h>
#include <asm/system.h>
#include <mach/hardware.h>
#include <asm/mach-types.h>

#include <asm/mach/pci.h>
#include <asm/mach/map.h>
#include <asm/mach/irq.h>
#include <asm/mach/time.h>
#include <asm/mach/flash.h>
#include <asm/mach/arch.h>

#include <mach/gpio.h>


/*************************************************************************
 * IXDP2x00 IRQ Initialization
 *************************************************************************/
static volatile unsigned long *board_irq_mask;
static volatile unsigned long *board_irq_stat;
static unsigned long board_irq_count;

#ifdef CONFIG_ARCH_IXDP2400
/*
 * Slowport configuration for accessing CPLD registers on IXDP2x00
 */
static struct slowport_cfg slowport_cpld_cfg = {
        .CCR =  SLOWPORT_CCR_DIV_2,
        .WTC = 0x00000070,
        .RTC = 0x00000070,
        .PCR = SLOWPORT_MODE_FLASH,
        .ADC = SLOWPORT_ADDR_WIDTH_24 | SLOWPORT_DATA_WIDTH_8
};
#endif

static void ixdp2x00_irq_mask(unsigned int irq)
{
        unsigned long dummy;
        static struct slowport_cfg old_cfg;

        /*
         * This is ugly in common code but really don't know
         * of a better way to handle it. :(
         */
#ifdef CONFIG_ARCH_IXDP2400
        if (machine_is_ixdp2400())
                ixp2000_acquire_slowport(&slowport_cpld_cfg, &old_cfg);
#endif

        dummy = *board_irq_mask;
        dummy |=  IXP2000_BOARD_IRQ_MASK(irq);
        ixp2000_reg_wrb(board_irq_mask, dummy);

#ifdef CONFIG_ARCH_IXDP2400
        if (machine_is_ixdp2400())
                ixp2000_release_slowport(&old_cfg);
#endif
}

static void ixdp2x00_irq_unmask(unsigned int irq)
{
        unsigned long dummy;
        static struct slowport_cfg old_cfg;

#ifdef CONFIG_ARCH_IXDP2400
        if (machine_is_ixdp2400())
                ixp2000_acquire_slowport(&slowport_cpld_cfg, &old_cfg);
#endif

        dummy = *board_irq_mask;
        dummy &=  ~IXP2000_BOARD_IRQ_MASK(irq);
        ixp2000_reg_wrb(board_irq_mask, dummy);

        if (machine_is_ixdp2400()) 
                ixp2000_release_slowport(&old_cfg);
}

static void ixdp2x00_irq_handler(unsigned int irq, struct irq_desc *desc)
{
        volatile u32 ex_interrupt = 0;
        static struct slowport_cfg old_cfg;
        int i;

        desc->chip->mask(irq);

#ifdef CONFIG_ARCH_IXDP2400
        if (machine_is_ixdp2400())
                ixp2000_acquire_slowport(&slowport_cpld_cfg, &old_cfg);
#endif
        ex_interrupt = *board_irq_stat & 0xff;
        if (machine_is_ixdp2400())
                ixp2000_release_slowport(&old_cfg);

        if(!ex_interrupt) {
                printk(KERN_ERR "Spurious IXDP2x00 CPLD interrupt!\n");
                return;
        }

        for(i = 0; i < board_irq_count; i++) {
                if(ex_interrupt & (1 << i))  {
                        int cpld_irq = IXP2000_BOARD_IRQ(0) + i;
                        generic_handle_irq(cpld_irq);
                }
        }

        desc->chip->unmask(irq);
}

static struct irq_chip ixdp2x00_cpld_irq_chip = {
        .ack    = ixdp2x00_irq_mask,
        .mask   = ixdp2x00_irq_mask,
        .unmask = ixdp2x00_irq_unmask
};

void __init ixdp2x00_init_irq(volatile unsigned long *stat_reg, volatile unsigned long *mask_reg, unsigned long nr_of_irqs)
{
        unsigned int irq;

        ixp2000_init_irq();
        
        if (!ixdp2x00_master_npu())
                return;

        board_irq_stat = stat_reg;
        board_irq_mask = mask_reg;
        board_irq_count = nr_of_irqs;

        *board_irq_mask = 0xffffffff;

        for(irq = IXP2000_BOARD_IRQ(0); irq < IXP2000_BOARD_IRQ(board_irq_count); irq++) {
                set_irq_chip(irq, &ixdp2x00_cpld_irq_chip);
                set_irq_handler(irq, handle_level_irq);
                set_irq_flags(irq, IRQF_VALID);
        }

        /* Hook into PCI interrupt */
        set_irq_chained_handler(IRQ_IXP2000_PCIB, ixdp2x00_irq_handler);
}

/*************************************************************************
 * IXDP2x00 memory map
 *************************************************************************/
static struct map_desc ixdp2x00_io_desc __initdata = {
        .virtual        = IXDP2X00_VIRT_CPLD_BASE, 
        .pfn            = __phys_to_pfn(IXDP2X00_PHYS_CPLD_BASE),
        .length         = IXDP2X00_CPLD_SIZE,
        .type           = MT_DEVICE
};

void __init ixdp2x00_map_io(void)
{
        ixp2000_map_io();       

        iotable_init(&ixdp2x00_io_desc, 1);
}

/*************************************************************************
 * IXDP2x00-common PCI init
 *
 * The IXDP2[48]00 has a horrid PCI bus layout. Basically the board 
 * contains two NPUs (ingress and egress) connected over PCI,  both running 
 * instances  of the kernel. So far so good. Peers on the PCI bus running 
 * Linux is a common design in telecom systems. The problem is that instead 
 * of all the devices being controlled by a single host, different
 * devices are controlled by different NPUs on the same bus, leading to
 * multiple hosts on the bus. The exact bus layout looks like:
 *
 *                   Bus 0
 *    Master NPU <-------------------+-------------------> Slave NPU
 *                                   |
 *                                   |
 *                                  P2P 
 *                                   |
 *
 *                  Bus 1            |
 *               <--+------+---------+---------+------+-->
 *                  |      |         |         |      |
 *                  |      |         |         |      |
 *             ... Dev    PMC       Media     Eth0   Eth1 ...
 *
 * The master controls all but Eth1, which is controlled by the
 * slave. What this means is that the both the master and the slave
 * have to scan the bus, but only one of them can enumerate the bus.
 * In addition, after the bus is scanned, each kernel must remove
 * the device(s) it does not control from the PCI dev list otherwise
 * a driver on each NPU will try to manage it and we will have horrible
 * conflicts. Oh..and the slave NPU needs to see the master NPU
 * for Intel's drivers to work properly. Closed source drivers...
 *
 * The way we deal with this is fairly simple but ugly:
 *
 * 1) Let master scan and enumerate the bus completely.
 * 2) Master deletes Eth1 from device list.
 * 3) Slave scans bus and then deletes all but Eth1 (Eth0 on slave)
 *    from device list.
 * 4) Find HW designers and LART them.
 *
 * The boards also do not do normal PCI IRQ routing, or any sort of 
 * sensical  swizzling, so we just need to check where on the  bus a
 * device sits and figure out to which CPLD pin the interrupt is routed.
 * See ixdp2[48]00.c files.
 *
 *************************************************************************/
void ixdp2x00_slave_pci_postinit(void)
{
        struct pci_dev *dev;

        /*
         * Remove PMC device is there is one
         */
        if((dev = pci_get_bus_and_slot(1, IXDP2X00_PMC_DEVFN))) {
                pci_remove_bus_device(dev);
                pci_dev_put(dev);
        }

        dev = pci_get_bus_and_slot(0, IXDP2X00_21555_DEVFN);
        pci_remove_bus_device(dev);
        pci_dev_put(dev);
}

/**************************************************************************
 * IXDP2x00 Machine Setup
 *************************************************************************/
static struct flash_platform_data ixdp2x00_platform_data = {
        .map_name       = "cfi_probe",
        .width          = 1,
};

static struct ixp2000_flash_data ixdp2x00_flash_data = {
        .platform_data  = &ixdp2x00_platform_data,
        .nr_banks       = 1
};

static struct resource ixdp2x00_flash_resource = {
        .start          = 0xc4000000,
        .end            = 0xc4000000 + 0x00ffffff,
        .flags          = IORESOURCE_MEM,
};

static struct platform_device ixdp2x00_flash = {
        .name           = "IXP2000-Flash",
        .id             = 0,
        .dev            = {
                .platform_data = &ixdp2x00_flash_data,
        },
        .num_resources  = 1,
        .resource       = &ixdp2x00_flash_resource,
};

static struct ixp2000_i2c_pins ixdp2x00_i2c_gpio_pins = {
        .sda_pin        = IXDP2X00_GPIO_SDA,
        .scl_pin        = IXDP2X00_GPIO_SCL,
};

static struct platform_device ixdp2x00_i2c_controller = {
        .name           = "IXP2000-I2C",
        .id             = 0,
        .dev            = {
                .platform_data = &ixdp2x00_i2c_gpio_pins,
        },
        .num_resources  = 0
};

static struct platform_device *ixdp2x00_devices[] __initdata = {
        &ixdp2x00_flash,
        &ixdp2x00_i2c_controller
};

void __init ixdp2x00_init_machine(void)
{
        gpio_line_set(IXDP2X00_GPIO_I2C_ENABLE, 1);
        gpio_line_config(IXDP2X00_GPIO_I2C_ENABLE, GPIO_OUT);

        platform_add_devices(ixdp2x00_devices, ARRAY_SIZE(ixdp2x00_devices));
        ixp2000_uart_init();
}