diff options
Diffstat (limited to 'drivers/media/pci/ivtv/ivtv-udma.c')
-rw-r--r-- | drivers/media/pci/ivtv/ivtv-udma.c | 234 |
1 files changed, 234 insertions, 0 deletions
diff --git a/drivers/media/pci/ivtv/ivtv-udma.c b/drivers/media/pci/ivtv/ivtv-udma.c new file mode 100644 index 000000000000..7338cb2d0a38 --- /dev/null +++ b/drivers/media/pci/ivtv/ivtv-udma.c @@ -0,0 +1,234 @@ +/* + User DMA + + Copyright (C) 2003-2004 Kevin Thayer <nufan_wfk at yahoo.com> + Copyright (C) 2004 Chris Kennedy <c@groovy.org> + Copyright (C) 2005-2007 Hans Verkuil <hverkuil@xs4all.nl> + + 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; either version 2 of the License, or + (at your option) any later version. + + 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 "ivtv-driver.h" +#include "ivtv-udma.h" + +void ivtv_udma_get_page_info(struct ivtv_dma_page_info *dma_page, unsigned long first, unsigned long size) +{ + dma_page->uaddr = first & PAGE_MASK; + dma_page->offset = first & ~PAGE_MASK; + dma_page->tail = 1 + ((first+size-1) & ~PAGE_MASK); + dma_page->first = (first & PAGE_MASK) >> PAGE_SHIFT; + dma_page->last = ((first+size-1) & PAGE_MASK) >> PAGE_SHIFT; + dma_page->page_count = dma_page->last - dma_page->first + 1; + if (dma_page->page_count == 1) dma_page->tail -= dma_page->offset; +} + +int ivtv_udma_fill_sg_list (struct ivtv_user_dma *dma, struct ivtv_dma_page_info *dma_page, int map_offset) +{ + int i, offset; + unsigned long flags; + + if (map_offset < 0) + return map_offset; + + offset = dma_page->offset; + + /* Fill SG Array with new values */ + for (i = 0; i < dma_page->page_count; i++) { + unsigned int len = (i == dma_page->page_count - 1) ? + dma_page->tail : PAGE_SIZE - offset; + + if (PageHighMem(dma->map[map_offset])) { + void *src; + + if (dma->bouncemap[map_offset] == NULL) + dma->bouncemap[map_offset] = alloc_page(GFP_KERNEL); + if (dma->bouncemap[map_offset] == NULL) + return -1; + local_irq_save(flags); + src = kmap_atomic(dma->map[map_offset]) + offset; + memcpy(page_address(dma->bouncemap[map_offset]) + offset, src, len); + kunmap_atomic(src); + local_irq_restore(flags); + sg_set_page(&dma->SGlist[map_offset], dma->bouncemap[map_offset], len, offset); + } + else { + sg_set_page(&dma->SGlist[map_offset], dma->map[map_offset], len, offset); + } + offset = 0; + map_offset++; + } + return map_offset; +} + +void ivtv_udma_fill_sg_array (struct ivtv_user_dma *dma, u32 buffer_offset, u32 buffer_offset_2, u32 split) { + int i; + struct scatterlist *sg; + + for (i = 0, sg = dma->SGlist; i < dma->SG_length; i++, sg++) { + dma->SGarray[i].size = cpu_to_le32(sg_dma_len(sg)); + dma->SGarray[i].src = cpu_to_le32(sg_dma_address(sg)); + dma->SGarray[i].dst = cpu_to_le32(buffer_offset); + buffer_offset += sg_dma_len(sg); + + split -= sg_dma_len(sg); + if (split == 0) + buffer_offset = buffer_offset_2; + } +} + +/* User DMA Buffers */ +void ivtv_udma_alloc(struct ivtv *itv) +{ + if (itv->udma.SG_handle == 0) { + /* Map DMA Page Array Buffer */ + itv->udma.SG_handle = pci_map_single(itv->pdev, itv->udma.SGarray, + sizeof(itv->udma.SGarray), PCI_DMA_TODEVICE); + ivtv_udma_sync_for_cpu(itv); + } +} + +int ivtv_udma_setup(struct ivtv *itv, unsigned long ivtv_dest_addr, + void __user *userbuf, int size_in_bytes) +{ + struct ivtv_dma_page_info user_dma; + struct ivtv_user_dma *dma = &itv->udma; + int i, err; + + IVTV_DEBUG_DMA("ivtv_udma_setup, dst: 0x%08x\n", (unsigned int)ivtv_dest_addr); + + /* Still in USE */ + if (dma->SG_length || dma->page_count) { + IVTV_DEBUG_WARN("ivtv_udma_setup: SG_length %d page_count %d still full?\n", + dma->SG_length, dma->page_count); + return -EBUSY; + } + + ivtv_udma_get_page_info(&user_dma, (unsigned long)userbuf, size_in_bytes); + + if (user_dma.page_count <= 0) { + IVTV_DEBUG_WARN("ivtv_udma_setup: Error %d page_count from %d bytes %d offset\n", + user_dma.page_count, size_in_bytes, user_dma.offset); + return -EINVAL; + } + + /* Get user pages for DMA Xfer */ + down_read(¤t->mm->mmap_sem); + err = get_user_pages(current, current->mm, + user_dma.uaddr, user_dma.page_count, 0, 1, dma->map, NULL); + up_read(¤t->mm->mmap_sem); + + if (user_dma.page_count != err) { + IVTV_DEBUG_WARN("failed to map user pages, returned %d instead of %d\n", + err, user_dma.page_count); + if (err >= 0) { + for (i = 0; i < err; i++) + put_page(dma->map[i]); + return -EINVAL; + } + return err; + } + + dma->page_count = user_dma.page_count; + + /* Fill SG List with new values */ + if (ivtv_udma_fill_sg_list(dma, &user_dma, 0) < 0) { + for (i = 0; i < dma->page_count; i++) { + put_page(dma->map[i]); + } + dma->page_count = 0; + return -ENOMEM; + } + + /* Map SG List */ + dma->SG_length = pci_map_sg(itv->pdev, dma->SGlist, dma->page_count, PCI_DMA_TODEVICE); + + /* Fill SG Array with new values */ + ivtv_udma_fill_sg_array (dma, ivtv_dest_addr, 0, -1); + + /* Tag SG Array with Interrupt Bit */ + dma->SGarray[dma->SG_length - 1].size |= cpu_to_le32(0x80000000); + + ivtv_udma_sync_for_device(itv); + return dma->page_count; +} + +void ivtv_udma_unmap(struct ivtv *itv) +{ + struct ivtv_user_dma *dma = &itv->udma; + int i; + + IVTV_DEBUG_INFO("ivtv_unmap_user_dma\n"); + + /* Nothing to free */ + if (dma->page_count == 0) + return; + + /* Unmap Scatterlist */ + if (dma->SG_length) { + pci_unmap_sg(itv->pdev, dma->SGlist, dma->page_count, PCI_DMA_TODEVICE); + dma->SG_length = 0; + } + /* sync DMA */ + ivtv_udma_sync_for_cpu(itv); + + /* Release User Pages */ + for (i = 0; i < dma->page_count; i++) { + put_page(dma->map[i]); + } + dma->page_count = 0; +} + +void ivtv_udma_free(struct ivtv *itv) +{ + int i; + + /* Unmap SG Array */ + if (itv->udma.SG_handle) { + pci_unmap_single(itv->pdev, itv->udma.SG_handle, + sizeof(itv->udma.SGarray), PCI_DMA_TODEVICE); + } + + /* Unmap Scatterlist */ + if (itv->udma.SG_length) { + pci_unmap_sg(itv->pdev, itv->udma.SGlist, itv->udma.page_count, PCI_DMA_TODEVICE); + } + + for (i = 0; i < IVTV_DMA_SG_OSD_ENT; i++) { + if (itv->udma.bouncemap[i]) + __free_page(itv->udma.bouncemap[i]); + } +} + +void ivtv_udma_start(struct ivtv *itv) +{ + IVTV_DEBUG_DMA("start UDMA\n"); + write_reg(itv->udma.SG_handle, IVTV_REG_DECDMAADDR); + write_reg_sync(read_reg(IVTV_REG_DMAXFER) | 0x01, IVTV_REG_DMAXFER); + set_bit(IVTV_F_I_DMA, &itv->i_flags); + set_bit(IVTV_F_I_UDMA, &itv->i_flags); + clear_bit(IVTV_F_I_UDMA_PENDING, &itv->i_flags); +} + +void ivtv_udma_prepare(struct ivtv *itv) +{ + unsigned long flags; + + spin_lock_irqsave(&itv->dma_reg_lock, flags); + if (!test_bit(IVTV_F_I_DMA, &itv->i_flags)) + ivtv_udma_start(itv); + else + set_bit(IVTV_F_I_UDMA_PENDING, &itv->i_flags); + spin_unlock_irqrestore(&itv->dma_reg_lock, flags); +} |