/*
 * pSeries_pci.c
 *
 * Copyright (C) 2001 Dave Engebretsen, IBM Corporation
 * Copyright (C) 2003 Anton Blanchard <anton@au.ibm.com>, IBM
 *
 * pSeries specific routines for PCI.
 * 
 * Based on code from pci.c and chrp_pci.c
 *
 * 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.
 *    
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */

#include <linux/kernel.h>
#include <linux/threads.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/bootmem.h>

#include <asm/io.h>
#include <asm/pgtable.h>
#include <asm/irq.h>
#include <asm/prom.h>
#include <asm/machdep.h>
#include <asm/pci-bridge.h>
#include <asm/ppcdebug.h>
#include <asm/naca.h>
#include <asm/iommu.h>
#include <asm/rtas.h>

#include "open_pic.h"
#include "pci.h"

/* RTAS tokens */
static int read_pci_config;
static int write_pci_config;
static int ibm_read_pci_config;
static int ibm_write_pci_config;

static int s7a_workaround;

extern unsigned long pci_probe_only;

static int rtas_read_config(struct device_node *dn, int where, int size, u32 *val)
{
	int returnval = -1;
	unsigned long buid, addr;
	int ret;

	if (!dn)
		return PCIBIOS_DEVICE_NOT_FOUND;
	if (where & (size - 1))
		return PCIBIOS_BAD_REGISTER_NUMBER;

	addr = (dn->busno << 16) | (dn->devfn << 8) | where;
	buid = dn->phb->buid;
	if (buid) {
		ret = rtas_call(ibm_read_pci_config, 4, 2, &returnval,
				addr, buid >> 32, buid & 0xffffffff, size);
	} else {
		ret = rtas_call(read_pci_config, 2, 2, &returnval, addr, size);
	}
	*val = returnval;

	if (ret)
		return PCIBIOS_DEVICE_NOT_FOUND;

	if (returnval == EEH_IO_ERROR_VALUE(size)
	    && eeh_dn_check_failure (dn, NULL))
		return PCIBIOS_DEVICE_NOT_FOUND;

	return PCIBIOS_SUCCESSFUL;
}

static int rtas_pci_read_config(struct pci_bus *bus,
				unsigned int devfn,
				int where, int size, u32 *val)
{
	struct device_node *busdn, *dn;

	if (bus->self)
		busdn = pci_device_to_OF_node(bus->self);
	else
		busdn = bus->sysdata;	/* must be a phb */

	/* Search only direct children of the bus */
	for (dn = busdn->child; dn; dn = dn->sibling)
		if (dn->devfn == devfn)
			return rtas_read_config(dn, where, size, val);
	return PCIBIOS_DEVICE_NOT_FOUND;
}

static int rtas_write_config(struct device_node *dn, int where, int size, u32 val)
{
	unsigned long buid, addr;
	int ret;

	if (!dn)
		return PCIBIOS_DEVICE_NOT_FOUND;
	if (where & (size - 1))
		return PCIBIOS_BAD_REGISTER_NUMBER;

	addr = (dn->busno << 16) | (dn->devfn << 8) | where;
	buid = dn->phb->buid;
	if (buid) {
		ret = rtas_call(ibm_write_pci_config, 5, 1, NULL, addr, buid >> 32, buid & 0xffffffff, size, (ulong) val);
	} else {
		ret = rtas_call(write_pci_config, 3, 1, NULL, addr, size, (ulong)val);
	}

	if (ret)
		return PCIBIOS_DEVICE_NOT_FOUND;

	return PCIBIOS_SUCCESSFUL;
}

static int rtas_pci_write_config(struct pci_bus *bus,
				 unsigned int devfn,
				 int where, int size, u32 val)
{
	struct device_node *busdn, *dn;

	if (bus->self)
		busdn = pci_device_to_OF_node(bus->self);
	else
		busdn = bus->sysdata;	/* must be a phb */

	/* Search only direct children of the bus */
	for (dn = busdn->child; dn; dn = dn->sibling)
		if (dn->devfn == devfn)
			return rtas_write_config(dn, where, size, val);
	return PCIBIOS_DEVICE_NOT_FOUND;
}

struct pci_ops rtas_pci_ops = {
	rtas_pci_read_config,
	rtas_pci_write_config
};

static void python_countermeasures(unsigned long addr)
{
	void *chip_regs;
	volatile u32 *tmp, i;

	/* Python's register file is 1 MB in size. */
	chip_regs = ioremap(addr & ~(0xfffffUL), 0x100000); 

	/* 
	 * Firmware doesn't always clear this bit which is critical
	 * for good performance - Anton
	 */

#define PRG_CL_RESET_VALID 0x00010000

	tmp = (u32 *)((unsigned long)chip_regs + 0xf6030);

	if (*tmp & PRG_CL_RESET_VALID) {
		printk(KERN_INFO "Python workaround: ");
		*tmp &= ~PRG_CL_RESET_VALID;
		/*
		 * We must read it back for changes to
		 * take effect
		 */
		i = *tmp;
		printk("reg0: %x\n", i);
	}

	iounmap(chip_regs);
}

void __init init_pci_config_tokens (void)
{
	read_pci_config = rtas_token("read-pci-config");
	write_pci_config = rtas_token("write-pci-config");
	ibm_read_pci_config = rtas_token("ibm,read-pci-config");
	ibm_write_pci_config = rtas_token("ibm,write-pci-config");
}

unsigned long __init get_phb_buid (struct device_node *phb)
{
	int addr_cells;
	unsigned int *buid_vals;
	unsigned int len;
	unsigned long buid;

	if (ibm_read_pci_config == -1) return 0;

	/* PHB's will always be children of the root node,
	 * or so it is promised by the current firmware. */
	if (phb->parent == NULL)
		return 0;
	if (phb->parent->parent)
		return 0;

	buid_vals = (unsigned int *) get_property(phb, "reg", &len);
	if (buid_vals == NULL)
		return 0;

	addr_cells = prom_n_addr_cells(phb);
	if (addr_cells == 1) {
		buid = (unsigned long) buid_vals[0];
	} else {
		buid = (((unsigned long)buid_vals[0]) << 32UL) |
			(((unsigned long)buid_vals[1]) & 0xffffffff);
	}
	return buid;
}

static struct pci_controller * __init alloc_phb(struct device_node *dev,
				 unsigned int addr_size_words)
{
	struct pci_controller *phb;
	unsigned int *ui_ptr = NULL, len;
	struct reg_property64 reg_struct;
	int *bus_range;
	char *model;
	enum phb_types phb_type;
 	struct property *of_prop;

	model = (char *)get_property(dev, "model", NULL);

	if (!model) {
		printk(KERN_ERR "alloc_phb: phb has no model property\n");
		model = "<empty>";
	}

	/* Found a PHB, now figure out where his registers are mapped. */
	ui_ptr = (unsigned int *) get_property(dev, "reg", &len);
	if (ui_ptr == NULL) {
		PPCDBG(PPCDBG_PHBINIT, "\tget reg failed.\n"); 
		return NULL;
	}

	if (addr_size_words == 1) {
		reg_struct.address = ((struct reg_property32 *)ui_ptr)->address;
		reg_struct.size    = ((struct reg_property32 *)ui_ptr)->size;
	} else {
		reg_struct = *((struct reg_property64 *)ui_ptr);
	}

	if (strstr(model, "Python")) {
		phb_type = phb_type_python;
	} else if (strstr(model, "Speedwagon")) {
		phb_type = phb_type_speedwagon;
	} else if (strstr(model, "Winnipeg")) {
		phb_type = phb_type_winnipeg;
	} else {
		printk(KERN_ERR "alloc_phb: unknown PHB %s\n", model);
		phb_type = phb_type_unknown;
	}

	phb = pci_alloc_pci_controller(phb_type);
	if (phb == NULL)
		return NULL;

	if (phb_type == phb_type_python)
		python_countermeasures(reg_struct.address);

	bus_range = (int *) get_property(dev, "bus-range", &len);
	if (bus_range == NULL || len < 2 * sizeof(int)) {
		kfree(phb);
		return NULL;
	}

	of_prop = (struct property *)alloc_bootmem(sizeof(struct property) +
			sizeof(phb->global_number));        

	if (!of_prop) {
		kfree(phb);
		return NULL;
	}

	memset(of_prop, 0, sizeof(struct property));
	of_prop->name = "linux,pci-domain";
	of_prop->length = sizeof(phb->global_number);
	of_prop->value = (unsigned char *)&of_prop[1];
	memcpy(of_prop->value, &phb->global_number, sizeof(phb->global_number));
	prom_add_property(dev, of_prop);

	phb->first_busno =  bus_range[0];
	phb->last_busno  =  bus_range[1];

	phb->arch_data   = dev;
	phb->ops = &rtas_pci_ops;

	phb->buid = get_phb_buid(dev);

	return phb;
}

unsigned long __init find_and_init_phbs(void)
{
	struct device_node *node;
	struct pci_controller *phb;
	unsigned int root_size_cells = 0;
	unsigned int index;
	unsigned int *opprop = NULL;
	struct device_node *root = of_find_node_by_path("/");

	if (naca->interrupt_controller == IC_OPEN_PIC) {
		opprop = (unsigned int *)get_property(root,
				"platform-open-pic", NULL);
	}

	root_size_cells = prom_n_size_cells(root);

	index = 0;

	for (node = of_get_next_child(root, NULL);
	     node != NULL;
	     node = of_get_next_child(root, node)) {
		if (node->type == NULL || strcmp(node->type, "pci") != 0)
			continue;

		phb = alloc_phb(node, root_size_cells);
		if (!phb)
			continue;

		pci_process_bridge_OF_ranges(phb, node, index == 0);

		if (naca->interrupt_controller == IC_OPEN_PIC) {
			int addr = root_size_cells * (index + 2) - 1;
			openpic_setup_ISU(index, opprop[addr]); 
		}

		index++;
	}

	of_node_put(root);
	pci_devs_phb_init();

	return 0;
}

#if 0
void pcibios_name_device(struct pci_dev *dev)
{
	struct device_node *dn;

	/*
	 * Add IBM loc code (slot) as a prefix to the device names for service
	 */
	dn = pci_device_to_OF_node(dev);
	if (dn) {
		char *loc_code = get_property(dn, "ibm,loc-code", 0);
		if (loc_code) {
			int loc_len = strlen(loc_code);
			if (loc_len < sizeof(dev->dev.name)) {
				memmove(dev->dev.name+loc_len+1, dev->dev.name,
					sizeof(dev->dev.name)-loc_len-1);
				memcpy(dev->dev.name, loc_code, loc_len);
				dev->dev.name[loc_len] = ' ';
				dev->dev.name[sizeof(dev->dev.name)-1] = '\0';
			}
		}
	}
}   
DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, pcibios_name_device);
#endif

static void check_s7a(void)
{
	struct device_node *root;
	char *model;

	root = of_find_node_by_path("/");
	if (root) {
		model = get_property(root, "model", NULL);
		if (model && !strcmp(model, "IBM,7013-S7A"))
			s7a_workaround = 1;
		of_node_put(root);
	}
}

static int get_bus_io_range(struct pci_bus *bus, unsigned long *start_phys,
				unsigned long *start_virt, unsigned long *size)
{
	struct pci_controller *hose = PCI_GET_PHB_PTR(bus);
	struct pci_bus_region region;
	struct resource *res;

	if (bus->self) {
		res = bus->resource[0];
		pcibios_resource_to_bus(bus->self, &region, res);
		*start_phys = hose->io_base_phys + region.start;
		*start_virt = (unsigned long) hose->io_base_virt + 
				region.start;
		if (region.end > region.start) 
			*size = region.end - region.start + 1;
		else {
			printk("%s(): unexpected region 0x%lx->0x%lx\n", 
					__FUNCTION__, region.start, region.end);
			return 1;
		}
		
	} else {
		/* Root Bus */
		res = &hose->io_resource;
		*start_phys = hose->io_base_phys;
		*start_virt = (unsigned long) hose->io_base_virt;
		if (res->end > res->start)
			*size = res->end - res->start + 1;
		else {
			printk("%s(): unexpected region 0x%lx->0x%lx\n", 
					__FUNCTION__, res->start, res->end);
			return 1;
		}
	}

	return 0;
}

int unmap_bus_range(struct pci_bus *bus)
{
	unsigned long start_phys;
	unsigned long start_virt;
	unsigned long size;

	if (!bus) {
		printk(KERN_ERR "%s() expected bus\n", __FUNCTION__);
		return 1;
	}
	
	if (get_bus_io_range(bus, &start_phys, &start_virt, &size))
		return 1;
	if (iounmap_explicit((void *) start_virt, size))
		return 1;

	return 0;
}
EXPORT_SYMBOL(unmap_bus_range);

int remap_bus_range(struct pci_bus *bus)
{
	unsigned long start_phys;
	unsigned long start_virt;
	unsigned long size;

	if (!bus) {
		printk(KERN_ERR "%s() expected bus\n", __FUNCTION__);
		return 1;
	}
	
	if (get_bus_io_range(bus, &start_phys, &start_virt, &size))
		return 1;
	if (__ioremap_explicit(start_phys, start_virt, size, _PAGE_NO_CACHE))
		return 1;

	return 0;
}
EXPORT_SYMBOL(remap_bus_range);

static void phbs_fixup_io(void)
{
	struct pci_controller *hose, *tmp;

	list_for_each_entry_safe(hose, tmp, &hose_list, list_node)
		remap_bus_range(hose->bus);
}

static void __init pSeries_request_regions(void)
{
	struct device_node *i8042;

	request_region(0x20,0x20,"pic1");
	request_region(0xa0,0x20,"pic2");
	request_region(0x00,0x20,"dma1");
	request_region(0x40,0x20,"timer");
	request_region(0x80,0x10,"dma page reg");
	request_region(0xc0,0x20,"dma2");

#define I8042_DATA_REG 0x60

	/*
	 * Some machines have an unterminated i8042 so check the device
	 * tree and reserve the region if it does not appear. Later on
	 * the i8042 code will try and reserve this region and fail.
	 */
	if (!(i8042 = of_find_node_by_type(NULL, "8042")))
		request_region(I8042_DATA_REG, 16, "reserved (no i8042)");
	of_node_put(i8042);
}

void __init pSeries_final_fixup(void)
{
	struct pci_dev *dev = NULL;

	check_s7a();

	while ((dev = pci_find_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
		pci_read_irq_line(dev);
		if (s7a_workaround) {
			if (dev->irq > 16) {
				dev->irq -= 3;
				pci_write_config_byte(dev, PCI_INTERRUPT_LINE, dev->irq);
			}
		}
	}

	phbs_fixup_io();
	pSeries_request_regions();
	pci_fix_bus_sysdata();

	if (!of_chosen || !get_property(of_chosen, "linux,iommu-off", NULL))
		iommu_setup_pSeries();

	pci_addr_cache_build();
}