From 1a758d4e847f7743ac1b5aa79fde3ba2d8b5132b Mon Sep 17 00:00:00 2001 From: Pawel Osciak Date: Mon, 11 Oct 2010 10:59:36 -0300 Subject: [PATCH] [media] v4l: videobuf2: add DMA coherent allocator Add an implementation of DMA coherent memory allocator and handling routines for videobuf2, implemented on top of dma_alloc_coherent() call. Signed-off-by: Pawel Osciak Signed-off-by: Kyungmin Park Signed-off-by: Marek Szyprowski CC: Pawel Osciak Reviewed-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/Kconfig | 5 + drivers/media/video/Makefile | 1 + drivers/media/video/videobuf2-dma-contig.c | 185 +++++++++++++++++++++ include/media/videobuf2-dma-contig.h | 29 ++++ 4 files changed, 220 insertions(+) create mode 100644 drivers/media/video/videobuf2-dma-contig.c create mode 100644 include/media/videobuf2-dma-contig.h diff --git a/drivers/media/video/Kconfig b/drivers/media/video/Kconfig index b8c21a729b86..b64183e06348 100644 --- a/drivers/media/video/Kconfig +++ b/drivers/media/video/Kconfig @@ -50,6 +50,11 @@ config VIDEOBUF2_CORE config VIDEOBUF2_MEMOPS tristate +config VIDEOBUF2_DMA_CONTIG + select VIDEOBUF2_CORE + select VIDEOBUF2_MEMOPS + tristate + config VIDEOBUF2_VMALLOC select VIDEOBUF2_CORE select VIDEOBUF2_MEMOPS diff --git a/drivers/media/video/Makefile b/drivers/media/video/Makefile index e31c88e9ca76..106d40bbe724 100644 --- a/drivers/media/video/Makefile +++ b/drivers/media/video/Makefile @@ -114,6 +114,7 @@ obj-$(CONFIG_VIDEO_BTCX) += btcx-risc.o obj-$(CONFIG_VIDEOBUF2_CORE) += videobuf2-core.o obj-$(CONFIG_VIDEOBUF2_MEMOPS) += videobuf2-memops.o obj-$(CONFIG_VIDEOBUF2_VMALLOC) += videobuf2-vmalloc.o +obj-$(CONFIG_VIDEOBUF2_DMA_CONTIG) += videobuf2-dma-contig.o obj-$(CONFIG_V4L2_MEM2MEM_DEV) += v4l2-mem2mem.o diff --git a/drivers/media/video/videobuf2-dma-contig.c b/drivers/media/video/videobuf2-dma-contig.c new file mode 100644 index 000000000000..bb6a5602cf94 --- /dev/null +++ b/drivers/media/video/videobuf2-dma-contig.c @@ -0,0 +1,185 @@ +/* + * videobuf2-dma-contig.c - DMA contig memory allocator for videobuf2 + * + * Copyright (C) 2010 Samsung Electronics + * + * Author: Pawel Osciak + * + * 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. + */ + +#include +#include +#include + +#include +#include + +struct vb2_dc_conf { + struct device *dev; +}; + +struct vb2_dc_buf { + struct vb2_dc_conf *conf; + void *vaddr; + dma_addr_t paddr; + unsigned long size; + struct vm_area_struct *vma; + atomic_t refcount; + struct vb2_vmarea_handler handler; +}; + +static void vb2_dma_contig_put(void *buf_priv); + +static void *vb2_dma_contig_alloc(void *alloc_ctx, unsigned long size) +{ + struct vb2_dc_conf *conf = alloc_ctx; + struct vb2_dc_buf *buf; + + buf = kzalloc(sizeof *buf, GFP_KERNEL); + if (!buf) + return ERR_PTR(-ENOMEM); + + buf->vaddr = dma_alloc_coherent(conf->dev, size, &buf->paddr, + GFP_KERNEL); + if (!buf->vaddr) { + dev_err(conf->dev, "dma_alloc_coherent of size %ld failed\n", + buf->size); + kfree(buf); + return ERR_PTR(-ENOMEM); + } + + buf->conf = conf; + buf->size = size; + + buf->handler.refcount = &buf->refcount; + buf->handler.put = vb2_dma_contig_put; + buf->handler.arg = buf; + + atomic_inc(&buf->refcount); + + return buf; +} + +static void vb2_dma_contig_put(void *buf_priv) +{ + struct vb2_dc_buf *buf = buf_priv; + + if (atomic_dec_and_test(&buf->refcount)) { + dma_free_coherent(buf->conf->dev, buf->size, buf->vaddr, + buf->paddr); + kfree(buf); + } +} + +static void *vb2_dma_contig_cookie(void *buf_priv) +{ + struct vb2_dc_buf *buf = buf_priv; + + return (void *)buf->paddr; +} + +static void *vb2_dma_contig_vaddr(void *buf_priv) +{ + struct vb2_dc_buf *buf = buf_priv; + if (!buf) + return 0; + + return buf->vaddr; +} + +static unsigned int vb2_dma_contig_num_users(void *buf_priv) +{ + struct vb2_dc_buf *buf = buf_priv; + + return atomic_read(&buf->refcount); +} + +static int vb2_dma_contig_mmap(void *buf_priv, struct vm_area_struct *vma) +{ + struct vb2_dc_buf *buf = buf_priv; + + if (!buf) { + printk(KERN_ERR "No buffer to map\n"); + return -EINVAL; + } + + return vb2_mmap_pfn_range(vma, buf->paddr, buf->size, + &vb2_common_vm_ops, &buf->handler); +} + +static void *vb2_dma_contig_get_userptr(void *alloc_ctx, unsigned long vaddr, + unsigned long size, int write) +{ + struct vb2_dc_buf *buf; + struct vm_area_struct *vma; + dma_addr_t paddr = 0; + int ret; + + buf = kzalloc(sizeof *buf, GFP_KERNEL); + if (!buf) + return ERR_PTR(-ENOMEM); + + ret = vb2_get_contig_userptr(vaddr, size, &vma, &paddr); + if (ret) { + printk(KERN_ERR "Failed acquiring VMA for vaddr 0x%08lx\n", + vaddr); + kfree(buf); + return ERR_PTR(ret); + } + + buf->size = size; + buf->paddr = paddr; + buf->vma = vma; + + return buf; +} + +static void vb2_dma_contig_put_userptr(void *mem_priv) +{ + struct vb2_dc_buf *buf = mem_priv; + + if (!buf) + return; + + vb2_put_vma(buf->vma); + kfree(buf); +} + +const struct vb2_mem_ops vb2_dma_contig_memops = { + .alloc = vb2_dma_contig_alloc, + .put = vb2_dma_contig_put, + .cookie = vb2_dma_contig_cookie, + .vaddr = vb2_dma_contig_vaddr, + .mmap = vb2_dma_contig_mmap, + .get_userptr = vb2_dma_contig_get_userptr, + .put_userptr = vb2_dma_contig_put_userptr, + .num_users = vb2_dma_contig_num_users, +}; +EXPORT_SYMBOL_GPL(vb2_dma_contig_memops); + +void *vb2_dma_contig_init_ctx(struct device *dev) +{ + struct vb2_dc_conf *conf; + + conf = kzalloc(sizeof *conf, GFP_KERNEL); + if (!conf) + return ERR_PTR(-ENOMEM); + + conf->dev = dev; + + return conf; +} +EXPORT_SYMBOL_GPL(vb2_dma_contig_init_ctx); + +void vb2_dma_contig_cleanup_ctx(void *alloc_ctx) +{ + kfree(alloc_ctx); +} +EXPORT_SYMBOL_GPL(vb2_dma_contig_cleanup_ctx); + +MODULE_DESCRIPTION("DMA-contig memory handling routines for videobuf2"); +MODULE_AUTHOR("Pawel Osciak"); +MODULE_LICENSE("GPL"); diff --git a/include/media/videobuf2-dma-contig.h b/include/media/videobuf2-dma-contig.h new file mode 100644 index 000000000000..fb7ca849d993 --- /dev/null +++ b/include/media/videobuf2-dma-contig.h @@ -0,0 +1,29 @@ +/* + * videobuf2-dma-coherent.h - DMA coherent memory allocator for videobuf2 + * + * Copyright (C) 2010 Samsung Electronics + * + * Author: Pawel Osciak + * + * 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. + */ + +#ifndef _MEDIA_VIDEOBUF2_DMA_COHERENT_H +#define _MEDIA_VIDEOBUF2_DMA_COHERENT_H + +#include + +static inline unsigned long vb2_dma_contig_plane_paddr( + struct vb2_buffer *vb, unsigned int plane_no) +{ + return (unsigned long)vb2_plane_cookie(vb, plane_no); +} + +void *vb2_dma_contig_init_ctx(struct device *dev); +void vb2_dma_contig_cleanup_ctx(void *alloc_ctx); + +extern const struct vb2_mem_ops vb2_dma_contig_memops; + +#endif -- 2.39.5