[POWERPC] Celleb: support iommu

/*

 * Support for IOMMU on Celleb platform.

 *

 * (C) Copyright 2006-2007 TOSHIBA CORPORATION

 *

 * 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.,

 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

 */

#include <linux/kernel.h>

#include <linux/init.h>

#include <linux/dma-mapping.h>

#include <linux/pci.h>

#include <asm/of_platform.h>

#include "beat_wrapper.h"

#define DMA_FLAGS 0xf800000000000000UL	/* r/w permitted, coherency required,

					   strongest order */

static int __init find_dma_window(u64 *io_space_id, u64 *ioid,

				  u64 *base, u64 *size, u64 *io_page_size)

{

	struct device_node *dn;

	const unsigned long *dma_window;

	for_each_node_by_type(dn, "ioif") {

		dma_window = get_property(dn, "toshiba,dma-window", NULL);

		if (dma_window) {

			*io_space_id = (dma_window[0] >> 32) & 0xffffffffUL;

			*ioid = dma_window[0] & 0x7ffUL;

			*base = dma_window[1];

			*size = dma_window[2];

			*io_page_size = 1 << dma_window[3];

			of_node_put(dn);

			return 1;

		}

	}

	return 0;

}

static void __init celleb_init_direct_mapping(void)

{

	u64 lpar_addr, io_addr;

	u64 io_space_id, ioid, dma_base, dma_size, io_page_size;

	if (!find_dma_window(&io_space_id, &ioid, &dma_base, &dma_size,

			     &io_page_size)) {

		pr_info("No dma window found !\n");

		return;

	}

	for (lpar_addr = 0; lpar_addr < dma_size; lpar_addr += io_page_size) {

		io_addr = lpar_addr + dma_base;

		(void)beat_put_iopte(io_space_id, io_addr, lpar_addr,

				     ioid, DMA_FLAGS);

	}

	dma_direct_offset = dma_base;

}

static int celleb_of_bus_notify(struct notifier_block *nb,

				unsigned long action, void *data)

{

	struct device *dev = data;

	/* We are only intereted in device addition */

	if (action != BUS_NOTIFY_ADD_DEVICE)

		return 0;

	dev->archdata.dma_ops = pci_dma_ops;

	return 0;

}

static struct notifier_block celleb_of_bus_notifier = {

	.notifier_call = celleb_of_bus_notify

};

static int __init celleb_init_iommu(void)

{

	if (!machine_is(celleb))

		return -ENODEV;

	celleb_init_direct_mapping();

	pci_dma_ops = &dma_direct_ops;

	bus_register_notifier(&of_platform_bus_type, &celleb_of_bus_notifier);

	return 0;

}

arch_initcall(celleb_init_iommu);