/*
 *	Find I2O capable controllers on the PCI bus, and register/install
 *	them with the I2O layer
 *
 *	(C) Copyright 1999   Red Hat Software
 *	
 *	Written by Alan Cox, Building Number Three Ltd
 * 	Modified by Deepak Saxena <deepak@plexity.net>
 * 	Modified by Boji T Kannanthanam <boji.t.kannanthanam@intel.com>
 *
 *	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.
 *
 *	TODO:
 *		Support polled I2O PCI controllers. 
 */

#include <linux/config.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/i2o.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <asm/io.h>

#ifdef CONFIG_MTRR
#include <asm/mtrr.h>
#endif // CONFIG_MTRR

#ifdef MODULE
/*
 * Core function table
 * See <include/linux/i2o.h> for an explanation
 */
static struct i2o_core_func_table *core;

/* Core attach function */
extern int i2o_pci_core_attach(struct i2o_core_func_table *);
extern void i2o_pci_core_detach(void);
#endif /* MODULE */

/*
 *	Free bus specific resources
 */
static void i2o_pci_dispose(struct i2o_controller *c)
{
	I2O_IRQ_WRITE32(c,0xFFFFFFFF);
	if(c->bus.pci.irq > 0)
		free_irq(c->bus.pci.irq, c);
	iounmap(((u8 *)c->post_port)-0x40);

#ifdef CONFIG_MTRR
	if(c->bus.pci.mtrr_reg0 > 0)
		mtrr_del(c->bus.pci.mtrr_reg0, 0, 0);
	if(c->bus.pci.mtrr_reg1 > 0)
		mtrr_del(c->bus.pci.mtrr_reg1, 0, 0);
#endif
}

/*
 *	No real bus specific handling yet (note that later we will
 *	need to 'steal' PCI devices on i960 mainboards)
 */
 
static int i2o_pci_bind(struct i2o_controller *c, struct i2o_device *dev)
{
	MOD_INC_USE_COUNT;
	return 0;
}

static int i2o_pci_unbind(struct i2o_controller *c, struct i2o_device *dev)
{
	MOD_DEC_USE_COUNT;
	return 0;
}

/*
 * Bus specific enable/disable functions
 */
static void i2o_pci_enable(struct i2o_controller *c)
{
	I2O_IRQ_WRITE32(c, 0);
	c->enabled = 1;
}

static void i2o_pci_disable(struct i2o_controller *c)
{
	I2O_IRQ_WRITE32(c, 0xFFFFFFFF);
	c->enabled = 0;
}

/*
 *	Bus specific interrupt handler
 */
 
static void i2o_pci_interrupt(int irq, void *dev_id, struct pt_regs *r)
{
	struct i2o_controller *c = dev_id;
#ifdef MODULE
	core->run_queue(c);
#else
	i2o_run_queue(c);
#endif /* MODULE */
}	

/*
 *	Install a PCI (or in theory AGP) i2o controller
 *
 * TODO: Add support for polled controllers
 */
int __init i2o_pci_install(struct pci_dev *dev)
{
	struct i2o_controller *c=kmalloc(sizeof(struct i2o_controller),
						GFP_KERNEL);
	u8 *mem;
	u32 memptr = 0;
	u32 size;
	
	int i;

	if(c==NULL)
	{
		printk(KERN_ERR "i2o: Insufficient memory to add controller.\n");
		return -ENOMEM;
	}
	memset(c, 0, sizeof(*c));

	for(i=0; i<6; i++)
	{
		/* Skip I/O spaces */
		if(!(pci_resource_flags(dev, i) & IORESOURCE_IO))
		{
			memptr = pci_resource_start(dev, i);
			break;
		}
	}
	
	if(i==6)
	{
		printk(KERN_ERR "i2o: I2O controller has no memory regions defined.\n");
		kfree(c);
		return -EINVAL;
	}
	
	size = dev->resource[i].end-dev->resource[i].start+1;	
	/* Map the I2O controller */
	
	printk(KERN_INFO "i2o: PCI I2O controller at 0x%08X size=%d\n", memptr, size);
	mem = ioremap(memptr, size);
	if(mem==NULL)
	{
		printk(KERN_ERR "i2o: Unable to map controller.\n");
		kfree(c);
		return -EINVAL;
	}

	c->bus.pci.irq = -1;

	c->irq_mask = (volatile u32 *)(mem+0x34);
	c->post_port = (volatile u32 *)(mem+0x40);
	c->reply_port = (volatile u32 *)(mem+0x44);

	c->mem_phys = memptr;
	c->mem_offset = (u32)mem;
	c->destructor = i2o_pci_dispose;
	
	c->bind = i2o_pci_bind;
	c->unbind = i2o_pci_unbind;
	c->bus_enable = i2o_pci_enable;
	c->bus_disable = i2o_pci_disable;
	
	c->type = I2O_TYPE_PCI;

	/* 
	 * Enable Write Combining MTRR for IOP's memory region
	 */
#ifdef CONFIG_MTRR
	c->bus.pci.mtrr_reg0 =
		mtrr_add(c->mem_phys, size, MTRR_TYPE_WRCOMB, 1);
/*
* If it is an INTEL i960 I/O processor then set the first 64K to Uncacheable
* since the region contains the Messaging unit which shouldn't be cached.
*/
	c->bus.pci.mtrr_reg1 = -1;
	if(dev->vendor == PCI_VENDOR_ID_INTEL)
	{
	printk(KERN_INFO "I2O: MTRR workaround for Intel i960 processor\n"); 
	c->bus.pci.mtrr_reg1 =
		mtrr_add(c->mem_phys, 65536, MTRR_TYPE_UNCACHABLE, 1);
	if(c->bus.pci.mtrr_reg1< 0)
		printk(KERN_INFO "i2o_pci: Error in setting MTRR_TYPE_UNCACHABLE\n");
	}

#endif

	I2O_IRQ_WRITE32(c,0xFFFFFFFF);

#ifdef MODULE
	i = core->install(c);
#else
	i = i2o_install_controller(c);
#endif /* MODULE */
	
	if(i<0)
	{
		printk(KERN_ERR "i2o: Unable to install controller.\n");
		kfree(c);
		iounmap(mem);
		return i;
	}

	c->bus.pci.irq = dev->irq;
	if(c->bus.pci.irq)
	{
		i=request_irq(dev->irq, i2o_pci_interrupt, SA_SHIRQ,
			c->name, c);
		if(i<0)
		{
			printk(KERN_ERR "%s: unable to allocate interrupt %d.\n",
				c->name, dev->irq);
			c->bus.pci.irq = -1;
#ifdef MODULE
			core->delete(c);
#else
			i2o_delete_controller(c);
#endif /* MODULE */	
			kfree(c);
			iounmap(mem);
			return -EBUSY;
		}
	}

	printk(KERN_INFO "%s: Installed at IRQ%d\n", c->name, dev->irq);
	I2O_IRQ_WRITE32(c,0x0);
	c->enabled = 1;
	return 0;	
}

int __init i2o_pci_scan(void)
{
	struct pci_dev *dev;
	int count=0;
	
	printk(KERN_INFO "i2o: Checking for PCI I2O controllers...\n");

	pci_for_each_dev(dev)	
	{
		if((dev->class>>8)!=PCI_CLASS_INTELLIGENT_I2O)
			continue;
		if((dev->class&0xFF)>1)
		{
			printk(KERN_INFO "i2o: I2O Controller found but does not support I2O 1.5 (skipping).\n");
			continue;
		}
		if (pci_enable_device(dev))
			continue;
		printk(KERN_INFO "i2o: I2O controller on bus %d at %d.\n",
			dev->bus->number, dev->devfn);
		pci_set_master(dev);
		if(i2o_pci_install(dev)==0)
			count++;
	}
	if(count)
		printk(KERN_INFO "i2o: %d I2O controller%s found and installed.\n", count,
			count==1?"":"s");
	return count?count:-ENODEV;
}

#ifdef I2O_HOTPLUG_SUPPORT
/*
 * Activate a newly found PCI I2O controller
 * Not used now, but will be needed in future for
 * hot plug PCI support
 */
static void i2o_pci_activate(i2o_controller * c)
{
	int i=0;
	struct i2o_controller *c;
	
	if(c->type == I2O_TYPE_PCI)
	{
		I2O_IRQ_WRITE32(c,0);
#ifdef MODULE
		if(core->activate(c))
#else
		if(i2o_activate_controller(c))
#endif /* MODULE */
		{
			printk("%s: Failed to initialize.\n", c->name);
#ifdef MODULE
			core->unlock(c);
			core->delete(c);
#else
			i2o_unlock_controller(c);
			i2o_delete_controller(c);
#endif
			continue;
		}
	}
}
#endif // I2O_HOTPLUG_SUPPORT

#ifdef MODULE

int i2o_pci_core_attach(struct i2o_core_func_table *table)
{
	MOD_INC_USE_COUNT;

	core = table;

	return i2o_pci_scan();
}

void i2o_pci_core_detach(void)
{
	core = NULL;

	MOD_DEC_USE_COUNT;
}

int init_module(void)
{
	printk(KERN_INFO "Linux I2O PCI support (c) 1999 Red Hat Software.\n");
	
	core = NULL;

 	return 0;
 
}

void cleanup_module(void)
{
}

EXPORT_SYMBOL(i2o_pci_core_attach);
EXPORT_SYMBOL(i2o_pci_core_detach);

MODULE_AUTHOR("Red Hat Software");
MODULE_DESCRIPTION("I2O PCI Interface");

#else
void __init i2o_pci_init(void)
{
	printk(KERN_INFO "Linux I2O PCI support (c) 1999 Red Hat Software.\n");
	i2o_pci_scan();
}
#endif
