drivers/char/agp/parisc-agp.c - kernel/msm - Gitiles

 /*
  * HP Quicksilver AGP GART routines
  *
  * Copyright (c) 2006, Kyle McMartin <kyle@parisc-linux.org>
  *
  * Based on drivers/char/agpgart/hp-agp.c which is
  * (c) Copyright 2002, 2003 Hewlett-Packard Development Company, L.P.
  *	Bjorn Helgaas <bjorn.helgaas@hp.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  *
  */

 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/init.h>
 #include <linux/klist.h>
 #include <linux/agp_backend.h>

 #include <asm-parisc/parisc-device.h>
 #include <asm-parisc/ropes.h>

 #include "agp.h"

 #define DRVNAME	"quicksilver"
 #define DRVPFX	DRVNAME ": "

 #ifndef log2
 #define log2(x)		ffz(~(x))
 #endif

 #define AGP8X_MODE_BIT		3
 #define AGP8X_MODE		(1 << AGP8X_MODE_BIT)

 static struct _parisc_agp_info {
 	void __iomem *ioc_regs;
 	void __iomem *lba_regs;

 	int lba_cap_offset;

 	u64 *gatt;
 	u64 gatt_entries;

 	u64 gart_base;
 	u64 gart_size;

 	int io_page_size;
 	int io_pages_per_kpage;
 } parisc_agp_info;

 static struct gatt_mask parisc_agp_masks[] =
 {
         {
 		.mask = SBA_PDIR_VALID_BIT,
 		.type = 0
 	}
 };

 static struct aper_size_info_fixed parisc_agp_sizes[] =
 {
         {0, 0, 0},              /* filled in by parisc_agp_fetch_size() */
 };

 static int
 parisc_agp_fetch_size(void)
 {
 	int size;

 	size = parisc_agp_info.gart_size / MB(1);
 	parisc_agp_sizes[0].size = size;
 	agp_bridge->current_size = (void *) &parisc_agp_sizes[0];

 	return size;
 }

 static int
 parisc_agp_configure(void)
 {
 	struct _parisc_agp_info *info = &parisc_agp_info;

 	agp_bridge->gart_bus_addr = info->gart_base;
 	agp_bridge->capndx = info->lba_cap_offset;
 	agp_bridge->mode = readl(info->lba_regs+info->lba_cap_offset+PCI_AGP_STATUS);

 	return 0;
 }

 static void
 parisc_agp_tlbflush(struct agp_memory *mem)
 {
 	struct _parisc_agp_info *info = &parisc_agp_info;

 	writeq(info->gart_base | log2(info->gart_size), info->ioc_regs+IOC_PCOM);
 	readq(info->ioc_regs+IOC_PCOM);	/* flush */
 }

 static int
 parisc_agp_create_gatt_table(struct agp_bridge_data *bridge)
 {
 	struct _parisc_agp_info *info = &parisc_agp_info;
 	int i;

 	for (i = 0; i < info->gatt_entries; i++) {
 		info->gatt[i] = (unsigned long)agp_bridge->scratch_page;
 	}

 	return 0;
 }

 static int
 parisc_agp_free_gatt_table(struct agp_bridge_data *bridge)
 {
 	struct _parisc_agp_info *info = &parisc_agp_info;

 	info->gatt[0] = SBA_AGPGART_COOKIE;

 	return 0;
 }

 static int
 parisc_agp_insert_memory(struct agp_memory *mem, off_t pg_start, int type)
 {
 	struct _parisc_agp_info *info = &parisc_agp_info;
 	int i, k;
 	off_t j, io_pg_start;
 	int io_pg_count;

 	if (type != 0 || mem->type != 0) {
 		return -EINVAL;
 	}

 	io_pg_start = info->io_pages_per_kpage * pg_start;
 	io_pg_count = info->io_pages_per_kpage * mem->page_count;
 	if ((io_pg_start + io_pg_count) > info->gatt_entries) {
 		return -EINVAL;
 	}

 	j = io_pg_start;
 	while (j < (io_pg_start + io_pg_count)) {
 		if (info->gatt[j])
 			return -EBUSY;
 		j++;
 	}

 	if (mem->is_flushed == FALSE) {
 		global_cache_flush();
 		mem->is_flushed = TRUE;
 	}

 	for (i = 0, j = io_pg_start; i < mem->page_count; i++) {
 		unsigned long paddr;

 		paddr = mem->memory[i];
 		for (k = 0;
 		     k < info->io_pages_per_kpage;
 		     k++, j++, paddr += info->io_page_size) {
 			info->gatt[j] =
 				agp_bridge->driver->mask_memory(agp_bridge,
 					paddr, type);
 		}
 	}

 	agp_bridge->driver->tlb_flush(mem);

 	return 0;
 }

 static int
 parisc_agp_remove_memory(struct agp_memory *mem, off_t pg_start, int type)
 {
 	struct _parisc_agp_info *info = &parisc_agp_info;
 	int i, io_pg_start, io_pg_count;

 	if (type != 0 || mem->type != 0) {
 		return -EINVAL;
 	}

 	io_pg_start = info->io_pages_per_kpage * pg_start;
 	io_pg_count = info->io_pages_per_kpage * mem->page_count;
 	for (i = io_pg_start; i < io_pg_count + io_pg_start; i++) {
 		info->gatt[i] = agp_bridge->scratch_page;
 	}

 	agp_bridge->driver->tlb_flush(mem);
 	return 0;
 }

 static unsigned long
 parisc_agp_mask_memory(struct agp_bridge_data *bridge,
 		    unsigned long addr, int type)
 {
 	return SBA_PDIR_VALID_BIT | addr;
 }

 static void
 parisc_agp_enable(struct agp_bridge_data *bridge, u32 mode)
 {
 	struct _parisc_agp_info *info = &parisc_agp_info;
 	u32 command;

 	command = readl(info->lba_regs + info->lba_cap_offset + PCI_AGP_STATUS);

 	command = agp_collect_device_status(bridge, mode, command);
 	command |= 0x00000100;

 	writel(command, info->lba_regs + info->lba_cap_offset + PCI_AGP_COMMAND);

 	agp_device_command(command, (mode & AGP8X_MODE) != 0);
 }

 struct agp_bridge_driver parisc_agp_driver = {
 	.owner			= THIS_MODULE,
 	.size_type		= FIXED_APER_SIZE,
 	.configure		= parisc_agp_configure,
 	.fetch_size		= parisc_agp_fetch_size,
 	.tlb_flush		= parisc_agp_tlbflush,
 	.mask_memory		= parisc_agp_mask_memory,
 	.masks			= parisc_agp_masks,
 	.agp_enable		= parisc_agp_enable,
 	.cache_flush		= global_cache_flush,
 	.create_gatt_table	= parisc_agp_create_gatt_table,
 	.free_gatt_table	= parisc_agp_free_gatt_table,
 	.insert_memory		= parisc_agp_insert_memory,
 	.remove_memory		= parisc_agp_remove_memory,
 	.alloc_by_type		= agp_generic_alloc_by_type,
 	.free_by_type		= agp_generic_free_by_type,
 	.agp_alloc_page		= agp_generic_alloc_page,
 	.agp_destroy_page	= agp_generic_destroy_page,
 	.agp_type_to_mask_type  = agp_generic_type_to_mask_type,
 	.cant_use_aperture	= 1,
 };

 static int __init
 agp_ioc_init(void __iomem *ioc_regs)
 {
 	struct _parisc_agp_info *info = &parisc_agp_info;
         u64 *iova_base, *io_pdir, io_tlb_ps;
         int io_tlb_shift;

         printk(KERN_INFO DRVPFX "IO PDIR shared with sba_iommu\n");

         info->ioc_regs = ioc_regs;

         io_tlb_ps = readq(info->ioc_regs+IOC_TCNFG);
         switch (io_tlb_ps) {
         case 0: io_tlb_shift = 12; break;
         case 1: io_tlb_shift = 13; break;
         case 2: io_tlb_shift = 14; break;
         case 3: io_tlb_shift = 16; break;
         default:
                 printk(KERN_ERR DRVPFX "Invalid IOTLB page size "
                        "configuration 0x%llx\n", io_tlb_ps);
                 info->gatt = NULL;
                 info->gatt_entries = 0;
                 return -ENODEV;
         }
         info->io_page_size = 1 << io_tlb_shift;
         info->io_pages_per_kpage = PAGE_SIZE / info->io_page_size;

         iova_base = readq(info->ioc_regs+IOC_IBASE) & ~0x1;
         info->gart_base = iova_base + PLUTO_IOVA_SIZE - PLUTO_GART_SIZE;

         info->gart_size = PLUTO_GART_SIZE;
         info->gatt_entries = info->gart_size / info->io_page_size;

         io_pdir = phys_to_virt(readq(info->ioc_regs+IOC_PDIR_BASE));
         info->gatt = &io_pdir[(PLUTO_IOVA_SIZE/2) >> PAGE_SHIFT];

         if (info->gatt[0] != SBA_AGPGART_COOKIE) {
                 info->gatt = NULL;
                 info->gatt_entries = 0;
                 printk(KERN_ERR DRVPFX "No reserved IO PDIR entry found; "
                        "GART disabled\n");
                 return -ENODEV;
         }

         return 0;
 }

 static int
 lba_find_capability(int cap)
 {
 	struct _parisc_agp_info *info = &parisc_agp_info;
         u16 status;
         u8 pos, id;
         int ttl = 48;

         status = readw(info->lba_regs + PCI_STATUS);
         if (!(status & PCI_STATUS_CAP_LIST))
                 return 0;
         pos = readb(info->lba_regs + PCI_CAPABILITY_LIST);
         while (ttl-- && pos >= 0x40) {
                 pos &= ~3;
                 id = readb(info->lba_regs + pos + PCI_CAP_LIST_ID);
                 if (id == 0xff)
                         break;
                 if (id == cap)
                         return pos;
                 pos = readb(info->lba_regs + pos + PCI_CAP_LIST_NEXT);
         }
         return 0;
 }

 static int __init
 agp_lba_init(void __iomem *lba_hpa)
 {
 	struct _parisc_agp_info *info = &parisc_agp_info;
         int cap;

 	info->lba_regs = lba_hpa;
         info->lba_cap_offset = lba_find_capability(PCI_CAP_ID_AGP);

         cap = readl(lba_hpa + info->lba_cap_offset) & 0xff;
         if (cap != PCI_CAP_ID_AGP) {
                 printk(KERN_ERR DRVPFX "Invalid capability ID 0x%02x at 0x%x\n",
                        cap, info->lba_cap_offset);
                 return -ENODEV;
         }

         return 0;
 }

 static int __init
 parisc_agp_setup(void __iomem *ioc_hpa, void __iomem *lba_hpa)
 {
 	struct pci_dev *fake_bridge_dev = NULL;
 	struct agp_bridge_data *bridge;
 	int error = 0;

 	fake_bridge_dev = kmalloc(sizeof (struct pci_dev), GFP_KERNEL);
 	if (!fake_bridge_dev) {
 		error = -ENOMEM;
 		goto fail;
 	}

 	error = agp_ioc_init(ioc_hpa);
 	if (error)
 		goto fail;

 	error = agp_lba_init(lba_hpa);
 	if (error)
 		goto fail;

 	bridge = agp_alloc_bridge();
 	if (!bridge) {
 		error = -ENOMEM;
 		goto fail;
 	}
 	bridge->driver = &parisc_agp_driver;

 	fake_bridge_dev->vendor = PCI_VENDOR_ID_HP;
 	fake_bridge_dev->device = PCI_DEVICE_ID_HP_PCIX_LBA;
 	bridge->dev = fake_bridge_dev;

 	error = agp_add_bridge(bridge);

 fail:
 	return error;
 }

 static struct device *next_device(struct klist_iter *i) {
 	struct klist_node * n = klist_next(i);
 	return n ? container_of(n, struct device, knode_parent) : NULL;
 }

 static int
 parisc_agp_init(void)
 {
 	extern struct sba_device *sba_list;

 	int err = -1;
 	struct parisc_device *sba = NULL, *lba = NULL;
 	struct lba_device *lbadev = NULL;
 	struct device *dev = NULL;
 	struct klist_iter i;

 	if (!sba_list)
 		goto out;

 	/* Find our parent Pluto */
 	sba = sba_list->dev;
 	if (!IS_PLUTO(sba)) {
 		printk(KERN_INFO DRVPFX "No Pluto found, so no AGPGART for you.\n");
 		goto out;
 	}

 	/* Now search our Pluto for our precious AGP device... */
 	klist_iter_init(&sba->dev.klist_children, &i);
 	while ((dev = next_device(&i))) {
 		struct parisc_device *padev = to_parisc_device(dev);
 		if (IS_QUICKSILVER(padev))
 			lba = padev;
 	}
 	klist_iter_exit(&i);

 	if (!lba) {
 		printk(KERN_INFO DRVPFX "No AGP devices found.\n");
 		goto out;
 	}

 	lbadev = parisc_get_drvdata(lba);

 	/* w00t, let's go find our cookies... */
 	parisc_agp_setup(sba_list->ioc[0].ioc_hpa, lbadev->hba.base_addr);

 	return 0;

 out:
 	return err;
 }

 module_init(parisc_agp_init);

 MODULE_AUTHOR("Kyle McMartin <kyle@parisc-linux.org>");
 MODULE_LICENSE("GPL");
	/*
	* HP Quicksilver AGP GART routines
	*
	* Copyright (c) 2006, Kyle McMartin <kyle@parisc-linux.org>
	*
	* Based on drivers/char/agpgart/hp-agp.c which is
	* (c) Copyright 2002, 2003 Hewlett-Packard Development Company, L.P.
	* Bjorn Helgaas <bjorn.helgaas@hp.com>
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*
	*/

	#include <linux/module.h>
	#include <linux/pci.h>
	#include <linux/init.h>
	#include <linux/klist.h>
	#include <linux/agp_backend.h>

	#include <asm-parisc/parisc-device.h>
	#include <asm-parisc/ropes.h>

	#include "agp.h"

	#define DRVNAME "quicksilver"
	#define DRVPFX DRVNAME ": "

	#ifndef log2
	#define log2(x) ffz(~(x))
	#endif

	#define AGP8X_MODE_BIT 3
	#define AGP8X_MODE (1 << AGP8X_MODE_BIT)

	static struct _parisc_agp_info {
	void __iomem *ioc_regs;
	void __iomem *lba_regs;

	int lba_cap_offset;

	u64 *gatt;
	u64 gatt_entries;

	u64 gart_base;
	u64 gart_size;

	int io_page_size;
	int io_pages_per_kpage;
	} parisc_agp_info;

	static struct gatt_mask parisc_agp_masks[] =
	{
	{
	.mask = SBA_PDIR_VALID_BIT,
	.type = 0
	}
	};

	static struct aper_size_info_fixed parisc_agp_sizes[] =
	{
	{0, 0, 0}, /* filled in by parisc_agp_fetch_size() */
	};

	static int
	parisc_agp_fetch_size(void)
	{
	int size;

	size = parisc_agp_info.gart_size / MB(1);
	parisc_agp_sizes[0].size = size;
	agp_bridge->current_size = (void *) &parisc_agp_sizes[0];

	return size;
	}

	static int
	parisc_agp_configure(void)
	{
	struct _parisc_agp_info *info = &parisc_agp_info;

	agp_bridge->gart_bus_addr = info->gart_base;
	agp_bridge->capndx = info->lba_cap_offset;
	agp_bridge->mode = readl(info->lba_regs+info->lba_cap_offset+PCI_AGP_STATUS);

	return 0;
	}

	static void
	parisc_agp_tlbflush(struct agp_memory *mem)
	{
	struct _parisc_agp_info *info = &parisc_agp_info;

	writeq(info->gart_base \| log2(info->gart_size), info->ioc_regs+IOC_PCOM);
	readq(info->ioc_regs+IOC_PCOM); /* flush */
	}

	static int
	parisc_agp_create_gatt_table(struct agp_bridge_data *bridge)
	{
	struct _parisc_agp_info *info = &parisc_agp_info;
	int i;

	for (i = 0; i < info->gatt_entries; i++) {
	info->gatt[i] = (unsigned long)agp_bridge->scratch_page;
	}

	return 0;
	}

	static int
	parisc_agp_free_gatt_table(struct agp_bridge_data *bridge)
	{
	struct _parisc_agp_info *info = &parisc_agp_info;

	info->gatt[0] = SBA_AGPGART_COOKIE;

	return 0;
	}

	static int
	parisc_agp_insert_memory(struct agp_memory *mem, off_t pg_start, int type)
	{
	struct _parisc_agp_info *info = &parisc_agp_info;
	int i, k;
	off_t j, io_pg_start;
	int io_pg_count;

	if (type != 0 \|\| mem->type != 0) {
	return -EINVAL;
	}

	io_pg_start = info->io_pages_per_kpage * pg_start;
	io_pg_count = info->io_pages_per_kpage * mem->page_count;
	if ((io_pg_start + io_pg_count) > info->gatt_entries) {
	return -EINVAL;
	}

	j = io_pg_start;
	while (j < (io_pg_start + io_pg_count)) {
	if (info->gatt[j])
	return -EBUSY;
	j++;
	}

	if (mem->is_flushed == FALSE) {
	global_cache_flush();
	mem->is_flushed = TRUE;
	}

	for (i = 0, j = io_pg_start; i < mem->page_count; i++) {
	unsigned long paddr;

	paddr = mem->memory[i];
	for (k = 0;
	k < info->io_pages_per_kpage;
	k++, j++, paddr += info->io_page_size) {
	info->gatt[j] =
	agp_bridge->driver->mask_memory(agp_bridge,
	paddr, type);
	}
	}

	agp_bridge->driver->tlb_flush(mem);

	return 0;
	}

	static int
	parisc_agp_remove_memory(struct agp_memory *mem, off_t pg_start, int type)
	{
	struct _parisc_agp_info *info = &parisc_agp_info;
	int i, io_pg_start, io_pg_count;

	if (type != 0 \|\| mem->type != 0) {
	return -EINVAL;
	}

	io_pg_start = info->io_pages_per_kpage * pg_start;
	io_pg_count = info->io_pages_per_kpage * mem->page_count;
	for (i = io_pg_start; i < io_pg_count + io_pg_start; i++) {
	info->gatt[i] = agp_bridge->scratch_page;
	}

	agp_bridge->driver->tlb_flush(mem);
	return 0;
	}

	static unsigned long
	parisc_agp_mask_memory(struct agp_bridge_data *bridge,
	unsigned long addr, int type)
	{
	return SBA_PDIR_VALID_BIT \| addr;
	}

	static void
	parisc_agp_enable(struct agp_bridge_data *bridge, u32 mode)
	{
	struct _parisc_agp_info *info = &parisc_agp_info;
	u32 command;

	command = readl(info->lba_regs + info->lba_cap_offset + PCI_AGP_STATUS);

	command = agp_collect_device_status(bridge, mode, command);
	command \|= 0x00000100;

	writel(command, info->lba_regs + info->lba_cap_offset + PCI_AGP_COMMAND);

	agp_device_command(command, (mode & AGP8X_MODE) != 0);
	}

	struct agp_bridge_driver parisc_agp_driver = {
	.owner = THIS_MODULE,
	.size_type = FIXED_APER_SIZE,
	.configure = parisc_agp_configure,
	.fetch_size = parisc_agp_fetch_size,
	.tlb_flush = parisc_agp_tlbflush,
	.mask_memory = parisc_agp_mask_memory,
	.masks = parisc_agp_masks,
	.agp_enable = parisc_agp_enable,
	.cache_flush = global_cache_flush,
	.create_gatt_table = parisc_agp_create_gatt_table,
	.free_gatt_table = parisc_agp_free_gatt_table,
	.insert_memory = parisc_agp_insert_memory,
	.remove_memory = parisc_agp_remove_memory,
	.alloc_by_type = agp_generic_alloc_by_type,
	.free_by_type = agp_generic_free_by_type,
	.agp_alloc_page = agp_generic_alloc_page,
	.agp_destroy_page = agp_generic_destroy_page,
	.agp_type_to_mask_type = agp_generic_type_to_mask_type,
	.cant_use_aperture = 1,
	};

	static int __init
	agp_ioc_init(void __iomem *ioc_regs)
	{
	struct _parisc_agp_info *info = &parisc_agp_info;
	u64 iova_base, io_pdir, io_tlb_ps;
	int io_tlb_shift;

	printk(KERN_INFO DRVPFX "IO PDIR shared with sba_iommu\n");

	info->ioc_regs = ioc_regs;

	io_tlb_ps = readq(info->ioc_regs+IOC_TCNFG);
	switch (io_tlb_ps) {
	case 0: io_tlb_shift = 12; break;
	case 1: io_tlb_shift = 13; break;
	case 2: io_tlb_shift = 14; break;
	case 3: io_tlb_shift = 16; break;
	default:
	printk(KERN_ERR DRVPFX "Invalid IOTLB page size "
	"configuration 0x%llx\n", io_tlb_ps);
	info->gatt = NULL;
	info->gatt_entries = 0;
	return -ENODEV;
	}
	info->io_page_size = 1 << io_tlb_shift;
	info->io_pages_per_kpage = PAGE_SIZE / info->io_page_size;

	iova_base = readq(info->ioc_regs+IOC_IBASE) & ~0x1;
	info->gart_base = iova_base + PLUTO_IOVA_SIZE - PLUTO_GART_SIZE;

	info->gart_size = PLUTO_GART_SIZE;
	info->gatt_entries = info->gart_size / info->io_page_size;

	io_pdir = phys_to_virt(readq(info->ioc_regs+IOC_PDIR_BASE));
	info->gatt = &io_pdir[(PLUTO_IOVA_SIZE/2) >> PAGE_SHIFT];

	if (info->gatt[0] != SBA_AGPGART_COOKIE) {
	info->gatt = NULL;
	info->gatt_entries = 0;
	printk(KERN_ERR DRVPFX "No reserved IO PDIR entry found; "
	"GART disabled\n");
	return -ENODEV;
	}

	return 0;
	}

	static int
	lba_find_capability(int cap)
	{
	struct _parisc_agp_info *info = &parisc_agp_info;
	u16 status;
	u8 pos, id;
	int ttl = 48;

	status = readw(info->lba_regs + PCI_STATUS);
	if (!(status & PCI_STATUS_CAP_LIST))
	return 0;
	pos = readb(info->lba_regs + PCI_CAPABILITY_LIST);
	while (ttl-- && pos >= 0x40) {
	pos &= ~3;
	id = readb(info->lba_regs + pos + PCI_CAP_LIST_ID);
	if (id == 0xff)
	break;
	if (id == cap)
	return pos;
	pos = readb(info->lba_regs + pos + PCI_CAP_LIST_NEXT);
	}
	return 0;
	}

	static int __init
	agp_lba_init(void __iomem *lba_hpa)
	{
	struct _parisc_agp_info *info = &parisc_agp_info;
	int cap;

	info->lba_regs = lba_hpa;
	info->lba_cap_offset = lba_find_capability(PCI_CAP_ID_AGP);

	cap = readl(lba_hpa + info->lba_cap_offset) & 0xff;
	if (cap != PCI_CAP_ID_AGP) {
	printk(KERN_ERR DRVPFX "Invalid capability ID 0x%02x at 0x%x\n",
	cap, info->lba_cap_offset);
	return -ENODEV;
	}

	return 0;
	}

	static int __init
	parisc_agp_setup(void __iomem ioc_hpa, void __iomem lba_hpa)
	{
	struct pci_dev *fake_bridge_dev = NULL;
	struct agp_bridge_data *bridge;
	int error = 0;

	fake_bridge_dev = kmalloc(sizeof (struct pci_dev), GFP_KERNEL);
	if (!fake_bridge_dev) {
	error = -ENOMEM;
	goto fail;
	}

	error = agp_ioc_init(ioc_hpa);
	if (error)
	goto fail;

	error = agp_lba_init(lba_hpa);
	if (error)
	goto fail;

	bridge = agp_alloc_bridge();
	if (!bridge) {
	error = -ENOMEM;
	goto fail;
	}
	bridge->driver = &parisc_agp_driver;

	fake_bridge_dev->vendor = PCI_VENDOR_ID_HP;
	fake_bridge_dev->device = PCI_DEVICE_ID_HP_PCIX_LBA;
	bridge->dev = fake_bridge_dev;

	error = agp_add_bridge(bridge);

	fail:
	return error;
	}

	static struct device next_device(struct klist_iter i) {
	struct klist_node * n = klist_next(i);
	return n ? container_of(n, struct device, knode_parent) : NULL;
	}

	static int
	parisc_agp_init(void)
	{
	extern struct sba_device *sba_list;

	int err = -1;
	struct parisc_device sba = NULL, lba = NULL;
	struct lba_device *lbadev = NULL;
	struct device *dev = NULL;
	struct klist_iter i;

	if (!sba_list)
	goto out;

	/* Find our parent Pluto */
	sba = sba_list->dev;
	if (!IS_PLUTO(sba)) {
	printk(KERN_INFO DRVPFX "No Pluto found, so no AGPGART for you.\n");
	goto out;
	}

	/* Now search our Pluto for our precious AGP device... */
	klist_iter_init(&sba->dev.klist_children, &i);
	while ((dev = next_device(&i))) {
	struct parisc_device *padev = to_parisc_device(dev);
	if (IS_QUICKSILVER(padev))
	lba = padev;
	}
	klist_iter_exit(&i);

	if (!lba) {
	printk(KERN_INFO DRVPFX "No AGP devices found.\n");
	goto out;
	}

	lbadev = parisc_get_drvdata(lba);

	/* w00t, let's go find our cookies... */
	parisc_agp_setup(sba_list->ioc[0].ioc_hpa, lbadev->hba.base_addr);

	return 0;

	out:
	return err;
	}

	module_init(parisc_agp_init);

	MODULE_AUTHOR("Kyle McMartin <kyle@parisc-linux.org>");
	MODULE_LICENSE("GPL");