/*
 * drivers/gpu/ion/omap_tiler_heap.c
 *
 * Copyright (C) 2011 Google, Inc.
 *
 * This software is licensed under the terms of the GNU General Public
 * License version 2, as published by the Free Software Foundation, and
 * may be copied, distributed, and modified under those terms.
 *
 * 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.
 *
 */
#include <linux/spinlock.h>

#include <linux/err.h>
#include <linux/genalloc.h>
#include <linux/io.h>
#include <linux/ion.h>
#include <linux/mm.h>
#include <linux/omap_ion.h>
#include <linux/scatterlist.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <mach/tiler.h>
#include <asm/cacheflush.h>
#include <asm/mach/map.h>
#include <asm/page.h>
#include <plat/common.h>

#include "../ion_priv.h"

bool use_dynamic_pages;
#define TILER_ENABLE_NON_PAGE_ALIGNED_ALLOCATIONS  1

struct omap_ion_heap {
	struct ion_heap heap;
	struct gen_pool *pool;
	ion_phys_addr_t base;
};

struct omap_tiler_info {
	tiler_blk_handle tiler_handle;  /* handle of the allocation intiler */
	bool lump;                      /* true for a single lump allocation */
	u32 n_phys_pages;               /* number of physical pages */
	u32 *phys_addrs;                /* array addrs of pages */
	u32 n_tiler_pages;              /* number of tiler pages */
	u32 *tiler_addrs;               /* array of addrs of tiler pages */
	int fmt;                        /* tiler buffer format */
	u32 tiler_start;                /* start addr in tiler -- if not page
					   aligned this may not equal the
					   first entry onf tiler_addrs */
};

static int omap_tiler_heap_allocate(struct ion_heap *heap,
				    struct ion_buffer *buffer,
				    unsigned long size, unsigned long align,
				    unsigned long flags)
{
	if (size == 0)
		return 0;

	pr_err("%s: This should never be called directly -- use the "
	       "OMAP_ION_TILER_ALLOC flag to the ION_IOC_CUSTOM "
	       "instead\n", __func__);
	return -EINVAL;
}

static int omap_tiler_alloc_carveout(struct ion_heap *heap,
				     struct omap_tiler_info *info)
{
	struct omap_ion_heap *omap_heap = (struct omap_ion_heap *)heap;
	int i;
	int ret;
	ion_phys_addr_t addr;

	addr = gen_pool_alloc(omap_heap->pool, info->n_phys_pages * PAGE_SIZE);
	if (addr) {
		info->lump = true;
		for (i = 0; i < info->n_phys_pages; i++)
			info->phys_addrs[i] = addr + i * PAGE_SIZE;
		return 0;
	}

	for (i = 0; i < info->n_phys_pages; i++) {
		addr = gen_pool_alloc(omap_heap->pool, PAGE_SIZE);

		if (addr == 0) {
			ret = -ENOMEM;
			pr_err("%s: failed to allocate pages to back "
			       "tiler address space\n", __func__);
			goto err;
		}
		info->phys_addrs[i] = addr;
	}
	return 0;

err:
	for (i -= 1; i >= 0; i--)
		gen_pool_free(omap_heap->pool, info->phys_addrs[i], PAGE_SIZE);
	return ret;
}

static void omap_tiler_free_carveout(struct ion_heap *heap,
				     struct omap_tiler_info *info)
{
	struct omap_ion_heap *omap_heap = (struct omap_ion_heap *)heap;
	int i;

	if (info->lump) {
		gen_pool_free(omap_heap->pool,
				info->phys_addrs[0],
				info->n_phys_pages * PAGE_SIZE);
		return;
	}

	for (i = 0; i < info->n_phys_pages; i++)
		gen_pool_free(omap_heap->pool, info->phys_addrs[i], PAGE_SIZE);
}

static int omap_tiler_alloc_dynamicpages(struct omap_tiler_info *info)
{
	int i;
	int ret;
	struct page *pg;

	for (i = 0; i < info->n_phys_pages; i++) {
		pg = alloc_page(GFP_KERNEL | GFP_DMA | GFP_HIGHUSER);
		if (!pg) {
			ret = -ENOMEM;
			pr_err("%s: alloc_page failed\n",
				__func__);
			goto err_page_alloc;
		}
		info->phys_addrs[i] = page_to_phys(pg);
		dmac_flush_range((void *)page_address(pg),
			(void *)page_address(pg) + PAGE_SIZE);
		outer_flush_range(info->phys_addrs[i],
			info->phys_addrs[i] + PAGE_SIZE);
	}
	return 0;

err_page_alloc:
	for (i -= 1; i >= 0; i--) {
		pg = phys_to_page(info->phys_addrs[i]);
		__free_page(pg);
	}
	return ret;
}

static void omap_tiler_free_dynamicpages(struct omap_tiler_info *info)
{
	int i;
	struct page *pg;

	for (i = 0; i < info->n_phys_pages; i++) {
		pg = phys_to_page(info->phys_addrs[i]);
		__free_page(pg);
	}
	return;
}

int omap_tiler_alloc(struct ion_heap *heap,
		     struct ion_client *client,
		     struct omap_ion_tiler_alloc_data *data)
{
	struct ion_handle *handle;
	struct ion_buffer *buffer;
	struct omap_tiler_info *info = NULL;
	u32 n_phys_pages;
	u32 n_tiler_pages;
	u32 tiler_start = 0;
	u32 v_size;
	tiler_blk_handle tiler_handle;
	int ret;

	if (data->fmt == TILER_PIXEL_FMT_PAGE && data->h != 1) {
		pr_err("%s: Page mode (1D) allocations must have a height "
		       "of one\n", __func__);
		return -EINVAL;
	}

	ret = tiler_memsize(data->fmt, data->w, data->h,
			    &n_phys_pages,
			    &n_tiler_pages);

	if (ret) {
		pr_err("%s: invalid tiler request w %u h %u fmt %u\n", __func__,
		       data->w, data->h, data->fmt);
		return ret;
	}

	BUG_ON(!n_phys_pages || !n_tiler_pages);

	if( (TILER_ENABLE_NON_PAGE_ALIGNED_ALLOCATIONS)
			&& (data->token != 0) ) {
		tiler_handle = tiler_alloc_block_area_aligned(data->fmt, data->w, data->h,
									    &tiler_start,
									    NULL,
									    data->out_align,
									    data->offset,
									    data->token);
	} else {
		tiler_handle = tiler_alloc_block_area(data->fmt, data->w, data->h,
							    &tiler_start,
							    NULL);
	}

	if (IS_ERR_OR_NULL(tiler_handle)) {
		ret = PTR_ERR(tiler_handle);
		pr_err("%s: failure to allocate address space from tiler\n",
		       __func__);
		goto err_nomem;
	}

	v_size = tiler_block_vsize(tiler_handle);

	if(!v_size)
		goto err_alloc;

	n_tiler_pages = (PAGE_ALIGN(v_size) / PAGE_SIZE);

	info = kzalloc(sizeof(struct omap_tiler_info) +
		       sizeof(u32) * n_phys_pages +
		       sizeof(u32) * n_tiler_pages, GFP_KERNEL);
	if (!info)
		goto err_alloc;

	info->tiler_handle = tiler_handle;
	info->tiler_start = tiler_start;
	info->n_phys_pages = n_phys_pages;
	info->n_tiler_pages = n_tiler_pages;
	info->phys_addrs = (u32 *)(info + 1);
	info->tiler_addrs = info->phys_addrs + n_phys_pages;
	info->fmt = data->fmt;

	if ((heap->id == OMAP_ION_HEAP_TILER) ||
	    (heap->id == OMAP_ION_HEAP_NONSECURE_TILER)) {
		if (use_dynamic_pages)
			ret = omap_tiler_alloc_dynamicpages(info);
		else
			ret = omap_tiler_alloc_carveout(heap, info);

		if (ret)
			goto err_alloc;

		ret = tiler_pin_block(info->tiler_handle, info->phys_addrs,
				      info->n_phys_pages);
		if (ret) {
			pr_err("%s: failure to pin pages to tiler\n",
				__func__);
			goto err_pin;
		}
	}
	data->stride = tiler_block_vstride(info->tiler_handle);

	/* create an ion handle  for the allocation */
	handle = ion_alloc(client, 0, 0, 1 << heap->id);
	if (IS_ERR_OR_NULL(handle)) {
		ret = PTR_ERR(handle);
		pr_err("%s: failure to allocate handle to manage tiler"
		       " allocation\n", __func__);
		goto err;
	}

	buffer = ion_handle_buffer(handle);
	buffer->heap = heap;	/* clarify tiler heap */
	buffer->size = v_size;
	buffer->priv_virt = info;
	data->handle = handle;
	data->offset = (size_t)(info->tiler_start & ~PAGE_MASK);

	if(tiler_fill_virt_array(tiler_handle, info->tiler_addrs,
			&n_tiler_pages) < 0) {
		pr_err("%s: failure filling tiler's virtual array %d\n",
				__func__, n_tiler_pages);
	}

	return 0;

err:
	tiler_unpin_block(info->tiler_handle);
err_pin:
	if ((heap->id == OMAP_ION_HEAP_TILER) ||
	    (heap->id == OMAP_ION_HEAP_NONSECURE_TILER)) {
		if (use_dynamic_pages)
			omap_tiler_free_dynamicpages(info);
		else
			omap_tiler_free_carveout(heap, info);
	}
err_alloc:
	tiler_free_block_area(tiler_handle);
err_nomem:
	kfree(info);
	return ret;
}

void omap_tiler_heap_free(struct ion_buffer *buffer)
{
	struct omap_tiler_info *info = buffer->priv_virt;

	tiler_unpin_block(info->tiler_handle);
	tiler_free_block_area(info->tiler_handle);

	if ((buffer->heap->id == OMAP_ION_HEAP_TILER) ||
	    (buffer->heap->id == OMAP_ION_HEAP_NONSECURE_TILER)) {
		if (use_dynamic_pages)
			omap_tiler_free_dynamicpages(info);
		else
			omap_tiler_free_carveout(buffer->heap, info);
	}

	kfree(info);
}

static int omap_tiler_phys(struct ion_heap *heap,
			   struct ion_buffer *buffer,
			   ion_phys_addr_t *addr, size_t *len)
{
	struct omap_tiler_info *info = buffer->priv_virt;

	*addr = info->tiler_start;
	*len = buffer->size;
	return 0;
}

int omap_tiler_pages(struct ion_client *client, struct ion_handle *handle,
		     int *n, u32 **tiler_addrs)
{
	ion_phys_addr_t addr;
	size_t len;
	int ret;
	struct omap_tiler_info *info = ion_handle_buffer(handle)->priv_virt;

	/* validate that the handle exists in this client */
	ret = ion_phys(client, handle, &addr, &len);
	if (ret)
		return ret;

	*n = info->n_tiler_pages;
	*tiler_addrs = info->tiler_addrs;
	return 0;
}
EXPORT_SYMBOL(omap_tiler_pages);

int omap_tiler_vinfo(struct ion_client *client, struct ion_handle *handle,
			unsigned int *vstride, unsigned int *vsize)
{
	struct omap_tiler_info *info = ion_handle_buffer(handle)->priv_virt;

	*vstride = tiler_block_vstride(info->tiler_handle);
	*vsize = tiler_block_vsize(info->tiler_handle);

	return 0;
}

int omap_tiler_heap_map_user(struct ion_heap *heap, struct ion_buffer *buffer,
			     struct vm_area_struct *vma)
{
	struct omap_tiler_info *info = buffer->priv_virt;
	unsigned long addr = vma->vm_start;
	u32 vma_pages = (vma->vm_end - vma->vm_start) / PAGE_SIZE;
	int n_pages = min(vma_pages, info->n_tiler_pages);
	int i, ret = 0;

	if (TILER_PIXEL_FMT_PAGE == info->fmt) {
		/* Since 1D buffer is linear, map whole buffer in one shot */
		ret = remap_pfn_range(vma, addr,
				 __phys_to_pfn(info->tiler_addrs[0]),
				(vma->vm_end - vma->vm_start),
				(buffer->cached ?
				(vma->vm_page_prot)
				: pgprot_writecombine(vma->vm_page_prot)));
	} else {
		for (i = vma->vm_pgoff; i < n_pages; i++, addr += PAGE_SIZE) {
			ret = remap_pfn_range(vma, addr,
				 __phys_to_pfn(info->tiler_addrs[i]),
				PAGE_SIZE,
				pgprot_writecombine(vma->vm_page_prot));
			if (ret)
				return ret;
		}
	}
	return ret;
}

static void per_cpu_cache_flush_arm(void *arg)
{
	   flush_cache_all();
}

int omap_tiler_cache_operation(struct ion_buffer *buffer, size_t len,
			unsigned long vaddr, enum cache_operation cacheop)
{
	struct omap_tiler_info *info;
	int n_pages;

	if (!buffer) {
		pr_err("%s(): buffer is NULL\n", __func__);
		return -EINVAL;
	}
	if (!buffer->cached) {
		pr_err("%s(): buffer not mapped as cacheable\n", __func__);
		return -EINVAL;
	}

	info = buffer->priv_virt;
	if (!info) {
		pr_err("%s(): tiler info of buffer is NULL\n", __func__);
		return -EINVAL;
	}

	n_pages = info->n_tiler_pages;
	if (len > (n_pages * PAGE_SIZE)) {
		pr_err("%s(): size to flush is greater than allocated size\n",
			__func__);
		return -EINVAL;
	}

	if (TILER_PIXEL_FMT_PAGE != info->fmt) {
		pr_err("%s(): only TILER 1D buffers can be cached\n",
			__func__);
		return -EINVAL;
	}

	if (len > FULL_CACHE_FLUSH_THRESHOLD) {
		on_each_cpu(per_cpu_cache_flush_arm, NULL, 1);
		outer_flush_all();
		return 0;
	}

	flush_cache_user_range(vaddr, vaddr + len);

	if (cacheop == CACHE_FLUSH)
		outer_flush_range(info->tiler_addrs[0],
			info->tiler_addrs[0] + len);
	else
		outer_inv_range(info->tiler_addrs[0],
			info->tiler_addrs[0] + len);
	return 0;
}

int omap_tiler_heap_flush_user(struct ion_buffer *buffer, size_t len,
			unsigned long vaddr)
{
	return omap_tiler_cache_operation(buffer, len, vaddr, CACHE_FLUSH);
}

int omap_tiler_heap_inval_user(struct ion_buffer *buffer, size_t len,
			unsigned long vaddr)
{
	return omap_tiler_cache_operation(buffer, len, vaddr, CACHE_INVALIDATE);
}

static struct ion_heap_ops omap_tiler_ops = {
	.allocate = omap_tiler_heap_allocate,
	.free = omap_tiler_heap_free,
	.phys = omap_tiler_phys,
	.map_user = omap_tiler_heap_map_user,
	.flush_user = omap_tiler_heap_flush_user,
	.inval_user = omap_tiler_heap_inval_user,
};

struct ion_heap *omap_tiler_heap_create(struct ion_platform_heap *data)
{
	struct omap_ion_heap *heap;

	heap = kzalloc(sizeof(struct omap_ion_heap), GFP_KERNEL);
	if (!heap)
		return ERR_PTR(-ENOMEM);

	if ((data->id == OMAP_ION_HEAP_TILER) ||
	    (data->id == OMAP_ION_HEAP_NONSECURE_TILER)) {
		heap->pool = gen_pool_create(12, -1);
		if (!heap->pool) {
			kfree(heap);
			return ERR_PTR(-ENOMEM);
		}
		heap->base = data->base;
		gen_pool_add(heap->pool, heap->base, data->size, -1);
	}
	heap->heap.ops = &omap_tiler_ops;
	heap->heap.type = OMAP_ION_HEAP_TYPE_TILER;
	heap->heap.name = data->name;
	heap->heap.id = data->id;

#ifdef CONFIG_ION_OMAP_TILER_DYNAMIC_ALLOC
	use_dynamic_pages = true;
#else
	if (omap_total_ram_size() <= SZ_512M)
		use_dynamic_pages = true;
	else
		use_dynamic_pages = false;
#endif

	return &heap->heap;
}

void omap_tiler_heap_destroy(struct ion_heap *heap)
{
	struct omap_ion_heap *omap_ion_heap = (struct omap_ion_heap *)heap;
	if (omap_ion_heap->pool)
		gen_pool_destroy(omap_ion_heap->pool);
	kfree(heap);
}