blob: 7431322379f64f5f804719e6fcb3a3c223f58fd7 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (C) 2018 Intel Corporation
* Copyright 2018 Google LLC.
*
* Author: Tomasz Figa <tfiga@chromium.org>
* Author: Yong Zhi <yong.zhi@intel.com>
*/
#include <linux/vmalloc.h>
#include "ipu3.h"
#include "ipu3-css-pool.h"
#include "ipu3-mmu.h"
#include "ipu3-dmamap.h"
/*
* Free a buffer allocated by imgu_dmamap_alloc_buffer()
*/
static void imgu_dmamap_free_buffer(struct page **pages,
size_t size)
{
int count = size >> PAGE_SHIFT;
while (count--)
__free_page(pages[count]);
kvfree(pages);
}
/*
* Based on the implementation of __iommu_dma_alloc_pages()
* defined in drivers/iommu/dma-iommu.c
*/
static struct page **imgu_dmamap_alloc_buffer(size_t size, gfp_t gfp)
{
struct page **pages;
unsigned int i = 0, count = size >> PAGE_SHIFT;
unsigned int order_mask = 1;
const gfp_t high_order_gfp = __GFP_NOWARN | __GFP_NORETRY;
/* Allocate mem for array of page ptrs */
pages = kvmalloc_array(count, sizeof(*pages), GFP_KERNEL);
if (!pages)
return NULL;
gfp |= __GFP_HIGHMEM | __GFP_ZERO;
while (count) {
struct page *page = NULL;
unsigned int order_size;
for (order_mask &= (2U << __fls(count)) - 1;
order_mask; order_mask &= ~order_size) {
unsigned int order = __fls(order_mask);
order_size = 1U << order;
page = alloc_pages((order_mask - order_size) ?
gfp | high_order_gfp : gfp, order);
if (!page)
continue;
if (!order)
break;
if (!PageCompound(page)) {
split_page(page, order);
break;
}
__free_pages(page, order);
}
if (!page) {
imgu_dmamap_free_buffer(pages, i << PAGE_SHIFT);
return NULL;
}
count -= order_size;
while (order_size--)
pages[i++] = page++;
}
return pages;
}
/**
* imgu_dmamap_alloc - allocate and map a buffer into KVA
* @imgu: struct device pointer
* @map: struct to store mapping variables
* @len: size required
*
* Returns:
* KVA on success
* %NULL on failure
*/
void *imgu_dmamap_alloc(struct imgu_device *imgu, struct imgu_css_map *map,
size_t len)
{
unsigned long shift = iova_shift(&imgu->iova_domain);
struct device *dev = &imgu->pci_dev->dev;
size_t size = PAGE_ALIGN(len);
struct page **pages;
dma_addr_t iovaddr;
struct iova *iova;
int i, rval;
dev_dbg(dev, "%s: allocating %zu\n", __func__, size);
iova = alloc_iova(&imgu->iova_domain, size >> shift,
imgu->mmu->aperture_end >> shift, 0);
if (!iova)
return NULL;
pages = imgu_dmamap_alloc_buffer(size, GFP_KERNEL);
if (!pages)
goto out_free_iova;
/* Call IOMMU driver to setup pgt */
iovaddr = iova_dma_addr(&imgu->iova_domain, iova);
for (i = 0; i < size / PAGE_SIZE; ++i) {
rval = imgu_mmu_map(imgu->mmu, iovaddr,
page_to_phys(pages[i]), PAGE_SIZE);
if (rval)
goto out_unmap;
iovaddr += PAGE_SIZE;
}
/* Now grab a virtual region */
map->vma = __get_vm_area(size, VM_USERMAP, VMALLOC_START, VMALLOC_END);
if (!map->vma)
goto out_unmap;
map->vma->pages = pages;
/* And map it in KVA */
if (map_vm_area(map->vma, PAGE_KERNEL, pages))
goto out_vunmap;
map->size = size;
map->daddr = iova_dma_addr(&imgu->iova_domain, iova);
map->vaddr = map->vma->addr;
dev_dbg(dev, "%s: allocated %zu @ IOVA %pad @ VA %p\n", __func__,
size, &map->daddr, map->vma->addr);
return map->vma->addr;
out_vunmap:
vunmap(map->vma->addr);
out_unmap:
imgu_dmamap_free_buffer(pages, size);
imgu_mmu_unmap(imgu->mmu, iova_dma_addr(&imgu->iova_domain, iova),
i * PAGE_SIZE);
map->vma = NULL;
out_free_iova:
__free_iova(&imgu->iova_domain, iova);
return NULL;
}
void imgu_dmamap_unmap(struct imgu_device *imgu, struct imgu_css_map *map)
{
struct iova *iova;
iova = find_iova(&imgu->iova_domain,
iova_pfn(&imgu->iova_domain, map->daddr));
if (WARN_ON(!iova))
return;
imgu_mmu_unmap(imgu->mmu, iova_dma_addr(&imgu->iova_domain, iova),
iova_size(iova) << iova_shift(&imgu->iova_domain));
__free_iova(&imgu->iova_domain, iova);
}
/*
* Counterpart of imgu_dmamap_alloc
*/
void imgu_dmamap_free(struct imgu_device *imgu, struct imgu_css_map *map)
{
struct vm_struct *area = map->vma;
dev_dbg(&imgu->pci_dev->dev, "%s: freeing %zu @ IOVA %pad @ VA %p\n",
__func__, map->size, &map->daddr, map->vaddr);
if (!map->vaddr)
return;
imgu_dmamap_unmap(imgu, map);
if (WARN_ON(!area) || WARN_ON(!area->pages))
return;
imgu_dmamap_free_buffer(area->pages, map->size);
vunmap(map->vaddr);
map->vaddr = NULL;
}
int imgu_dmamap_map_sg(struct imgu_device *imgu, struct scatterlist *sglist,
int nents, struct imgu_css_map *map)
{
unsigned long shift = iova_shift(&imgu->iova_domain);
struct scatterlist *sg;
struct iova *iova;
size_t size = 0;
int i;
for_each_sg(sglist, sg, nents, i) {
if (sg->offset)
return -EINVAL;
if (i != nents - 1 && !PAGE_ALIGNED(sg->length))
return -EINVAL;
size += sg->length;
}
size = iova_align(&imgu->iova_domain, size);
dev_dbg(&imgu->pci_dev->dev, "dmamap: mapping sg %d entries, %zu pages\n",
nents, size >> shift);
iova = alloc_iova(&imgu->iova_domain, size >> shift,
imgu->mmu->aperture_end >> shift, 0);
if (!iova)
return -ENOMEM;
dev_dbg(&imgu->pci_dev->dev, "dmamap: iova low pfn %lu, high pfn %lu\n",
iova->pfn_lo, iova->pfn_hi);
if (imgu_mmu_map_sg(imgu->mmu, iova_dma_addr(&imgu->iova_domain, iova),
sglist, nents) < size)
goto out_fail;
memset(map, 0, sizeof(*map));
map->daddr = iova_dma_addr(&imgu->iova_domain, iova);
map->size = size;
return 0;
out_fail:
__free_iova(&imgu->iova_domain, iova);
return -EFAULT;
}
int imgu_dmamap_init(struct imgu_device *imgu)
{
unsigned long order, base_pfn;
int ret = iova_cache_get();
if (ret)
return ret;
order = __ffs(IPU3_PAGE_SIZE);
base_pfn = max_t(unsigned long, 1, imgu->mmu->aperture_start >> order);
init_iova_domain(&imgu->iova_domain, 1UL << order, base_pfn);
return 0;
}
void imgu_dmamap_exit(struct imgu_device *imgu)
{
put_iova_domain(&imgu->iova_domain);
iova_cache_put();
}