From: Tomasz Figa <tfiga@xxxxxxxxxxxx>
This patch adds driver to support IPU3-specific
MMU-aware memory alloc/free and sg mapping functions.
Signed-off-by: Tomasz Figa <tfiga@xxxxxxxxxxxx>
Signed-off-by: Yong Zhi <yong.zhi@xxxxxxxxx>
---
drivers/media/pci/intel/ipu3/Kconfig | 7 +
drivers/media/pci/intel/ipu3/Makefile | 2 +-
drivers/media/pci/intel/ipu3/ipu3-dmamap.c | 342 +++++++++++++++++++++++++++++
drivers/media/pci/intel/ipu3/ipu3-dmamap.h | 33 +++
4 files changed, 383 insertions(+), 1 deletion(-)
create mode 100644 drivers/media/pci/intel/ipu3/ipu3-dmamap.c
create mode 100644 drivers/media/pci/intel/ipu3/ipu3-dmamap.h
diff --git a/drivers/media/pci/intel/ipu3/Kconfig b/drivers/media/pci/intel/ipu3/Kconfig
index 46ff138f3e50..d7dab52dc881 100644
--- a/drivers/media/pci/intel/ipu3/Kconfig
+++ b/drivers/media/pci/intel/ipu3/Kconfig
@@ -26,3 +26,10 @@ config INTEL_IPU3_MMU
---help---
For IPU3, this option enables its MMU driver to translate its internal
virtual address to 39 bits wide physical address for 64GBytes space access.
+
+config INTEL_IPU3_DMAMAP
+ tristate
+ default n
+ select IOMMU_IOVA
+ ---help---
+ This is IPU3 IOMMU domain specific DMA driver.
diff --git a/drivers/media/pci/intel/ipu3/Makefile b/drivers/media/pci/intel/ipu3/Makefile
index 91cac9cb7401..651773231496 100644
--- a/drivers/media/pci/intel/ipu3/Makefile
+++ b/drivers/media/pci/intel/ipu3/Makefile
@@ -13,4 +13,4 @@
obj-$(CONFIG_VIDEO_IPU3_CIO2) += ipu3-cio2.o
obj-$(CONFIG_INTEL_IPU3_MMU) += ipu3-mmu.o
-
+obj-$(CONFIG_INTEL_IPU3_DMAMAP) += ipu3-dmamap.o
diff --git a/drivers/media/pci/intel/ipu3/ipu3-dmamap.c b/drivers/media/pci/intel/ipu3/ipu3-dmamap.c
new file mode 100644
index 000000000000..e54bd9dfa302
--- /dev/null
+++ b/drivers/media/pci/intel/ipu3/ipu3-dmamap.c
@@ -0,0 +1,342 @@
+/*
+ * Copyright (c) 2017 Intel Corporation.
+ * Copyright (C) 2017 Google, Inc.
+ *
+ * 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.
+ *
+ * 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/dma-direction.h>
+#include <linux/highmem.h>
+#include <linux/iommu.h>
+#include <linux/iova.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/version.h>
+#include <linux/vmalloc.h>
+
+#include "ipu3-css-pool.h"
+#include "ipu3.h"
+
+/*
+ * Based on arch/arm64/mm/dma-mapping.c, with simplifications possible due
+ * to driver-specific character of this file.
+ */
+
+static int dma_direction_to_prot(enum dma_data_direction dir, bool coherent)
+{
+ int prot = coherent ? IOMMU_CACHE : 0;
+
+ switch (dir) {
+ case DMA_BIDIRECTIONAL:
+ return prot | IOMMU_READ | IOMMU_WRITE;
+ case DMA_TO_DEVICE:
+ return prot | IOMMU_READ;
+ case DMA_FROM_DEVICE:
+ return prot | IOMMU_WRITE;
+ default:
+ return 0;
+ }
+}
+
+/*
+ * Free a buffer allocated by ipu3_dmamap_alloc_buffer()
+ */
+static void ipu3_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 **ipu3_dmamap_alloc_buffer(size_t size,
+ unsigned long order_mask,
+ gfp_t gfp)
+{
+ struct page **pages;
+ unsigned int i = 0, count = size >> PAGE_SHIFT;
+ const gfp_t high_order_gfp = __GFP_NOWARN | __GFP_NORETRY;
+
+ /* Allocate mem for array of page ptrs */
+ pages = kvmalloc_array(count, sizeof(struct page *), GFP_KERNEL);
+
+ if (!pages)
+ return NULL;
+
+ order_mask &= (2U << MAX_ORDER) - 1;
+ if (!order_mask)
+ return NULL;
+
+ gfp |= __GFP_NOWARN | __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) {
+ ipu3_dmamap_free_buffer(pages, i << PAGE_SHIFT);
+ return NULL;
+ }
+ count -= order_size;
+ while (order_size--)
+ pages[i++] = page++;
+ }
+
+ return pages;
+}
+
+/**
+ * ipu3_dmamap_alloc - allocate and map a buffer into KVA
+ * @dev: struct device pointer
+ * @map: struct to store mapping variables
+ * @len: size required
+ *
+ * Return KVA on success or NULL on failure
+ */
+void *ipu3_dmamap_alloc(struct imgu_device *imgu, struct ipu3_css_map *map,
+ size_t len)
+{
+ unsigned long shift = iova_shift(&imgu->iova_domain);
+ unsigned int alloc_sizes = imgu->domain->pgsize_bitmap;
+ size_t size = PAGE_ALIGN(len);
+ struct page **pages;
+ dma_addr_t iovaddr;
+ struct iova *iova;
+ int i, rval;
+
+ if (WARN(!(&imgu->pci_dev->dev),
+ "cannot create IOMMU mapping for unknown device\n"))
+ return NULL;
+
+ dev_dbg(&imgu->pci_dev->dev, "%s: allocating %zu\n", __func__, size);
+
+ iova = alloc_iova(&imgu->iova_domain, size >> shift,
+ imgu->domain->geometry.aperture_end >> shift, 0);
+ if (!iova)
+ return NULL;
+
+ pages = ipu3_dmamap_alloc_buffer(size, alloc_sizes >> PAGE_SHIFT,
+ 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 = iommu_map(imgu->domain, iovaddr,
+ page_to_phys(pages[i]), PAGE_SIZE, 0);
+ 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(&imgu->pci_dev->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:
+ ipu3_dmamap_free_buffer(pages, size);
+ iommu_unmap(imgu->domain, iova_dma_addr(&imgu->iova_domain, iova),
+ i * PAGE_SIZE);
+ map->vma = NULL;
+
+out_free_iova:
+ __free_iova(&imgu->iova_domain, iova);
+
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(ipu3_dmamap_alloc);
+
+void ipu3_dmamap_unmap(struct imgu_device *imgu, struct ipu3_css_map *map)
+{
+ struct iova *iova;
+
+ iova = find_iova(&imgu->iova_domain,
+ iova_pfn(&imgu->iova_domain, map->daddr));
+ if (WARN_ON(!iova))
+ return;
+
+ iommu_unmap(imgu->domain, iova_dma_addr(&imgu->iova_domain, iova),
+ iova_size(iova) << iova_shift(&imgu->iova_domain));
+
+ __free_iova(&imgu->iova_domain, iova);
+}
+EXPORT_SYMBOL_GPL(ipu3_dmamap_unmap);
+
+/*
+ * Counterpart of ipu3_dmamap_alloc
+ */
+void ipu3_dmamap_free(struct imgu_device *imgu, struct ipu3_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;
+
+ ipu3_dmamap_unmap(imgu, map);
+
+ if (WARN_ON(!area) || WARN_ON(!area->pages))
+ return;
+
+ ipu3_dmamap_free_buffer(area->pages, map->size);
+ vunmap(map->vaddr);
+ map->vaddr = NULL;
+}
+EXPORT_SYMBOL_GPL(ipu3_dmamap_free);
+
+int ipu3_dmamap_map_sg(struct imgu_device *imgu, struct scatterlist *sglist,
+ int nents, enum dma_data_direction dir,
+ struct ipu3_css_map *map)
+{
+ unsigned long shift = iova_shift(&imgu->iova_domain);
+ struct scatterlist *sg;
+ struct iova *iova;
+ size_t size = 0;
+ size_t size_aligned;
+ 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_aligned = PAGE_ALIGN(size);
+
+ dev_dbg(&imgu->pci_dev->dev, "dmamap: mapping sg %d entries, %zu pages\n",
+ nents, size_aligned >> shift);
+
+ iova = alloc_iova(&imgu->iova_domain, size_aligned >> shift,
+ imgu->domain->geometry.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 (iommu_map_sg(imgu->domain,
+ iova_dma_addr(&imgu->iova_domain, iova),
+ sglist, nents, dma_direction_to_prot(dir, true))
+ < size)
+ goto out_fail;
+
+ memset(map, 0, sizeof(*map));
+ map->daddr = iova_dma_addr(&imgu->iova_domain, iova);
+ map->size = size_aligned;
+
+ return 0;
+
+out_fail:
+ __free_iova(&imgu->iova_domain, iova);
+
+ return -EFAULT;
+}
+EXPORT_SYMBOL_GPL(ipu3_dmamap_map_sg);
+
+int ipu3_dmamap_init(struct imgu_device *imgu)
+{
+ unsigned long order, base_pfn, end_pfn;
+ int ret;
+
+ imgu->domain = iommu_domain_alloc(imgu->mmu->bus);
+ if (!imgu->domain)
+ return -ENOMEM;
+
+ ret = iova_cache_get();
+ if (ret)
+ goto out_domain;
+
+ order = __ffs(imgu->domain->pgsize_bitmap);
+ base_pfn = max_t(unsigned long, 1,
+ imgu->domain->geometry.aperture_start >> order);
+ end_pfn = imgu->domain->geometry.aperture_end >> order;
+
+ init_iova_domain(&imgu->iova_domain, 1UL << order, base_pfn, end_pfn);
+
+ ret = iommu_attach_device(imgu->domain, imgu->mmu);
+ if (ret)
+ goto out_iova_cache;
+
+ return 0;
+
+out_iova_cache:
+ iova_cache_put();
+ put_iova_domain(&imgu->iova_domain);
+out_domain:
+ iommu_domain_free(imgu->domain);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(ipu3_dmamap_init);
+
+void ipu3_dmamap_exit(struct imgu_device *imgu)
+{
+ put_iova_domain(&imgu->iova_domain);
+ iova_cache_put();
+ iommu_detach_device(imgu->domain, imgu->mmu);
+ iommu_domain_free(imgu->domain);
+ imgu->domain = NULL;
+}
+EXPORT_SYMBOL_GPL(ipu3_dmamap_exit);
+
+MODULE_AUTHOR("Tomasz Figa <tfiga@xxxxxxxxxxxx>");
+MODULE_AUTHOR("Yong Zhi <yong.zhi@xxxxxxxxx>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("IPU3 DMA mapping support");
diff --git a/drivers/media/pci/intel/ipu3/ipu3-dmamap.h b/drivers/media/pci/intel/ipu3/ipu3-dmamap.h
new file mode 100644
index 000000000000..9b442a40ee06
--- /dev/null
+++ b/drivers/media/pci/intel/ipu3/ipu3-dmamap.h
@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2017 Intel Corporation.
+ * Copyright (C) 2017 Google, Inc.
+ *
+ * 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.
+ *
+ * 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.
+ *
+ */
+
+#ifndef __IPU3_DMAMAP_H
+#define __IPU3_DMAMAP_H
+
+struct imgu_device;
+
+void *ipu3_dmamap_alloc(struct imgu_device *imgu, struct ipu3_css_map *map,
+ size_t len);
+void ipu3_dmamap_free(struct imgu_device *imgu, struct ipu3_css_map *map);
+
+int ipu3_dmamap_map_sg(struct imgu_device *imgu, struct scatterlist *sglist,
+ int nents, enum dma_data_direction dir,
+ struct ipu3_css_map *map);
+void ipu3_dmamap_unmap(struct imgu_device *imgu, struct ipu3_css_map *map);
+
+int ipu3_dmamap_init(struct imgu_device *imgu);
+void ipu3_dmamap_exit(struct imgu_device *imgu);
+
+#endif
--
2.7.4
