| /* |
| 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-streams.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; |
| |
| dma->SGlist[map_offset].length = len; |
| dma->SGlist[map_offset].offset = 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], KM_BOUNCE_READ) + offset; |
| memcpy(page_address(dma->bouncemap[map_offset]) + offset, src, len); |
| kunmap_atomic(src, KM_BOUNCE_READ); |
| local_irq_restore(flags); |
| dma->SGlist[map_offset].page = dma->bouncemap[map_offset]; |
| } |
| else { |
| dma->SGlist[map_offset].page = dma->map[map_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->dev, 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); |
| return -EINVAL; |
| } |
| |
| 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->dev, 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->dev, 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->dev, itv->udma.SG_handle, |
| sizeof(itv->udma.SGarray), PCI_DMA_TODEVICE); |
| } |
| |
| /* Unmap Scatterlist */ |
| if (itv->udma.SG_length) { |
| pci_unmap_sg(itv->dev, 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); |
| } |
| |
| 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); |
| } |