/*
 *  PS3 system bus driver.
 *
 *  Copyright (C) 2006 Sony Computer Entertainment Inc.
 *  Copyright 2006 Sony Corp.
 *
 *  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; version 2 of the License.
 *
 *  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/init.h>
#include <linux/module.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>

#include <asm/udbg.h>
#include <asm/ps3.h>
#include <asm/lv1call.h>
#include <asm/firmware.h>

#define dump_mmio_region(_a) _dump_mmio_region(_a, __func__, __LINE__)
static void _dump_mmio_region(const struct ps3_mmio_region* r,
	const char* func, int line)
{
	pr_debug("%s:%d: dev       %u:%u\n", func, line, r->did.bus_id,
		r->did.dev_id);
	pr_debug("%s:%d: bus_addr  %lxh\n", func, line, r->bus_addr);
	pr_debug("%s:%d: len       %lxh\n", func, line, r->len);
	pr_debug("%s:%d: lpar_addr %lxh\n", func, line, r->lpar_addr);
}

int ps3_mmio_region_create(struct ps3_mmio_region *r)
{
	int result;

	result = lv1_map_device_mmio_region(r->did.bus_id, r->did.dev_id,
		r->bus_addr, r->len, r->page_size, &r->lpar_addr);

	if (result) {
		pr_debug("%s:%d: lv1_map_device_mmio_region failed: %s\n",
			__func__, __LINE__, ps3_result(result));
		r->lpar_addr = r->len = r->bus_addr = 0;
	}

	dump_mmio_region(r);
	return result;
}

int ps3_free_mmio_region(struct ps3_mmio_region *r)
{
	int result;

	result = lv1_unmap_device_mmio_region(r->did.bus_id, r->did.dev_id,
		r->bus_addr);

	if (result)
		pr_debug("%s:%d: lv1_unmap_device_mmio_region failed: %s\n",
			__func__, __LINE__, ps3_result(result));

	r->lpar_addr = r->len = r->bus_addr = 0;
	return result;
}

static int ps3_system_bus_match(struct device *_dev,
	struct device_driver *_drv)
{
	int result;
	struct ps3_system_bus_driver *drv = to_ps3_system_bus_driver(_drv);
	struct ps3_system_bus_device *dev = to_ps3_system_bus_device(_dev);

	result = dev->match_id == drv->match_id;

	pr_info("%s:%d: dev=%u(%s), drv=%u(%s): %s\n", __func__, __LINE__,
		dev->match_id, dev->core.bus_id, drv->match_id, drv->core.name,
		(result ? "match" : "miss"));
	return result;
}

static int ps3_system_bus_probe(struct device *_dev)
{
	int result;
	struct ps3_system_bus_device *dev = to_ps3_system_bus_device(_dev);
	struct ps3_system_bus_driver *drv =
		to_ps3_system_bus_driver(_dev->driver);

	result = lv1_open_device(dev->did.bus_id, dev->did.dev_id, 0);

	if (result) {
		pr_debug("%s:%d: lv1_open_device failed (%d)\n",
			__func__, __LINE__, result);
		result = -EACCES;
		goto clean_none;
	}

	if (dev->d_region->did.bus_id) {
		result = ps3_dma_region_create(dev->d_region);

		if (result) {
			pr_debug("%s:%d: ps3_dma_region_create failed (%d)\n",
				__func__, __LINE__, result);
			BUG_ON("check region type");
			result = -EINVAL;
			goto clean_device;
		}
	}

	BUG_ON(!drv);

	if (drv->probe)
		result = drv->probe(dev);
	else
		pr_info("%s:%d: %s no probe method\n", __func__, __LINE__,
			dev->core.bus_id);

	if (result) {
		pr_debug("%s:%d: drv->probe failed\n", __func__, __LINE__);
		goto clean_dma;
	}

	return result;

clean_dma:
	ps3_dma_region_free(dev->d_region);
clean_device:
	lv1_close_device(dev->did.bus_id, dev->did.dev_id);
clean_none:
	return result;
}

static int ps3_system_bus_remove(struct device *_dev)
{
	struct ps3_system_bus_device *dev = to_ps3_system_bus_device(_dev);
	struct ps3_system_bus_driver *drv =
		to_ps3_system_bus_driver(_dev->driver);

	if (drv->remove)
		drv->remove(dev);
	else
		pr_info("%s:%d: %s no remove method\n", __func__, __LINE__,
			dev->core.bus_id);

	ps3_dma_region_free(dev->d_region);
	ps3_free_mmio_region(dev->m_region);
	lv1_close_device(dev->did.bus_id, dev->did.dev_id);

	return 0;
}

struct bus_type ps3_system_bus_type = {
        .name = "ps3_system_bus",
	.match = ps3_system_bus_match,
	.probe = ps3_system_bus_probe,
	.remove = ps3_system_bus_remove,
};

int __init ps3_system_bus_init(void)
{
	int result;

	if (!firmware_has_feature(FW_FEATURE_PS3_LV1))
		return 0;

	result = bus_register(&ps3_system_bus_type);
	BUG_ON(result);
	return result;
}

core_initcall(ps3_system_bus_init);

/* Allocates a contiguous real buffer and creates mappings over it.
 * Returns the virtual address of the buffer and sets dma_handle
 * to the dma address (mapping) of the first page.
 */

static void * ps3_alloc_coherent(struct device *_dev, size_t size,
	dma_addr_t *dma_handle, gfp_t flag)
{
	int result;
	struct ps3_system_bus_device *dev = to_ps3_system_bus_device(_dev);
	unsigned long virt_addr;

	BUG_ON(!dev->d_region->bus_addr);

	flag &= ~(__GFP_DMA | __GFP_HIGHMEM);
	flag |= __GFP_ZERO;

	virt_addr = __get_free_pages(flag, get_order(size));

	if (!virt_addr) {
		pr_debug("%s:%d: get_free_pages failed\n", __func__, __LINE__);
		goto clean_none;
	}

	result = ps3_dma_map(dev->d_region, virt_addr, size, dma_handle);

	if (result) {
		pr_debug("%s:%d: ps3_dma_map failed (%d)\n",
			__func__, __LINE__, result);
		BUG_ON("check region type");
		goto clean_alloc;
	}

	return (void*)virt_addr;

clean_alloc:
	free_pages(virt_addr, get_order(size));
clean_none:
	dma_handle = NULL;
	return NULL;
}

static void ps3_free_coherent(struct device *_dev, size_t size, void *vaddr,
	dma_addr_t dma_handle)
{
	struct ps3_system_bus_device *dev = to_ps3_system_bus_device(_dev);

	ps3_dma_unmap(dev->d_region, dma_handle, size);
	free_pages((unsigned long)vaddr, get_order(size));
}

/* Creates TCEs for a user provided buffer.  The user buffer must be
 * contiguous real kernel storage (not vmalloc).  The address of the buffer
 * passed here is the kernel (virtual) address of the buffer.  The buffer
 * need not be page aligned, the dma_addr_t returned will point to the same
 * byte within the page as vaddr.
 */

static dma_addr_t ps3_map_single(struct device *_dev, void *ptr, size_t size,
	enum dma_data_direction direction)
{
	struct ps3_system_bus_device *dev = to_ps3_system_bus_device(_dev);
	int result;
	unsigned long bus_addr;

	result = ps3_dma_map(dev->d_region, (unsigned long)ptr, size,
		&bus_addr);

	if (result) {
		pr_debug("%s:%d: ps3_dma_map failed (%d)\n",
			__func__, __LINE__, result);
	}

	return bus_addr;
}

static void ps3_unmap_single(struct device *_dev, dma_addr_t dma_addr,
	size_t size, enum dma_data_direction direction)
{
	struct ps3_system_bus_device *dev = to_ps3_system_bus_device(_dev);
	int result;

	result = ps3_dma_unmap(dev->d_region, dma_addr, size);

	if (result) {
		pr_debug("%s:%d: ps3_dma_unmap failed (%d)\n",
			__func__, __LINE__, result);
	}
}

static int ps3_map_sg(struct device *_dev, struct scatterlist *sg, int nents,
	enum dma_data_direction direction)
{
#if defined(CONFIG_PS3_DYNAMIC_DMA)
	BUG_ON("do");
#endif
	return 0;
}

static void ps3_unmap_sg(struct device *_dev, struct scatterlist *sg,
	int nents, enum dma_data_direction direction)
{
#if defined(CONFIG_PS3_DYNAMIC_DMA)
	BUG_ON("do");
#endif
}

static int ps3_dma_supported(struct device *_dev, u64 mask)
{
	return 1;
}

static struct dma_mapping_ops ps3_dma_ops = {
	.alloc_coherent = ps3_alloc_coherent,
	.free_coherent = ps3_free_coherent,
	.map_single = ps3_map_single,
	.unmap_single = ps3_unmap_single,
	.map_sg = ps3_map_sg,
	.unmap_sg = ps3_unmap_sg,
	.dma_supported = ps3_dma_supported
};

/**
 * ps3_system_bus_release_device - remove a device from the system bus
 */

static void ps3_system_bus_release_device(struct device *_dev)
{
	struct ps3_system_bus_device *dev = to_ps3_system_bus_device(_dev);
	kfree(dev);
}

/**
 * ps3_system_bus_device_register - add a device to the system bus
 *
 * ps3_system_bus_device_register() expects the dev object to be allocated
 * dynamically by the caller.  The system bus takes ownership of the dev
 * object and frees the object in ps3_system_bus_release_device().
 */

int ps3_system_bus_device_register(struct ps3_system_bus_device *dev)
{
	int result;
	static unsigned int dev_count = 1;

	dev->core.parent = NULL;
	dev->core.bus = &ps3_system_bus_type;
	dev->core.release = ps3_system_bus_release_device;

	dev->core.archdata.of_node = NULL;
	dev->core.archdata.dma_ops = &ps3_dma_ops;
	dev->core.archdata.numa_node = 0;

	snprintf(dev->core.bus_id, sizeof(dev->core.bus_id), "sb_%02x",
		dev_count++);

	pr_debug("%s:%d add %s\n", __func__, __LINE__, dev->core.bus_id);

	result = device_register(&dev->core);
	return result;
}

EXPORT_SYMBOL_GPL(ps3_system_bus_device_register);

int ps3_system_bus_driver_register(struct ps3_system_bus_driver *drv)
{
	int result;

	drv->core.bus = &ps3_system_bus_type;

	result = driver_register(&drv->core);
	return result;
}

EXPORT_SYMBOL_GPL(ps3_system_bus_driver_register);

void ps3_system_bus_driver_unregister(struct ps3_system_bus_driver *drv)
{
	driver_unregister(&drv->core);
}

EXPORT_SYMBOL_GPL(ps3_system_bus_driver_unregister);