1 // SPDX-License-Identifier: GPL-2.0-or-later
5     Copyright (C) 2003-2004  Kevin Thayer <nufan_wfk at yahoo.com>
6     Copyright (C) 2004  Chris Kennedy <c@groovy.org>
7     Copyright (C) 2005-2007  Hans Verkuil <hverkuil@xs4all.nl>
11 #include "ivtv-driver.h"
12 #include "ivtv-udma.h"
16 	dma_page->uaddr = first & PAGE_MASK;  in ivtv_udma_get_page_info()
17 	dma_page->offset = first & ~PAGE_MASK;  in ivtv_udma_get_page_info()
18 	dma_page->tail = 1 + ((first+size-1) & ~PAGE_MASK);  in ivtv_udma_get_page_info()
19 	dma_page->first = (first & PAGE_MASK) >> PAGE_SHIFT;  in ivtv_udma_get_page_info()
20 	dma_page->last = ((first+size-1) & PAGE_MASK) >> PAGE_SHIFT;  in ivtv_udma_get_page_info()
21 	dma_page->page_count = dma_page->last - dma_page->first + 1;  in ivtv_udma_get_page_info()
22 	if (dma_page->page_count == 1) dma_page->tail -= dma_page->offset;  in ivtv_udma_get_page_info()
33 	offset = dma_page->offset;  in ivtv_udma_fill_sg_list()
36 	for (i = 0; i < dma_page->page_count; i++) {  in ivtv_udma_fill_sg_list()
37 		unsigned int len = (i == dma_page->page_count - 1) ?  in ivtv_udma_fill_sg_list()
38 			dma_page->tail : PAGE_SIZE - offset;  in ivtv_udma_fill_sg_list()
40 		if (PageHighMem(dma->map[map_offset])) {  in ivtv_udma_fill_sg_list()
43 			if (dma->bouncemap[map_offset] == NULL)  in ivtv_udma_fill_sg_list()
44 				dma->bouncemap[map_offset] = alloc_page(GFP_KERNEL);  in ivtv_udma_fill_sg_list()
45 			if (dma->bouncemap[map_offset] == NULL)  in ivtv_udma_fill_sg_list()
46 				return -1;  in ivtv_udma_fill_sg_list()
48 			src = kmap_atomic(dma->map[map_offset]) + offset;  in ivtv_udma_fill_sg_list()
49 			memcpy(page_address(dma->bouncemap[map_offset]) + offset, src, len);  in ivtv_udma_fill_sg_list()
52 			sg_set_page(&dma->SGlist[map_offset], dma->bouncemap[map_offset], len, offset);  in ivtv_udma_fill_sg_list()
55 			sg_set_page(&dma->SGlist[map_offset], dma->map[map_offset], len, offset);  in ivtv_udma_fill_sg_list()
67 	for_each_sg(dma->SGlist, sg, dma->SG_length, i) {  in ivtv_udma_fill_sg_array()
68 		dma->SGarray[i].size = cpu_to_le32(sg_dma_len(sg));  in ivtv_udma_fill_sg_array()
69 		dma->SGarray[i].src = cpu_to_le32(sg_dma_address(sg));  in ivtv_udma_fill_sg_array()
70 		dma->SGarray[i].dst = cpu_to_le32(buffer_offset);  in ivtv_udma_fill_sg_array()
73 		split -= sg_dma_len(sg);  in ivtv_udma_fill_sg_array()
82 	if (itv->udma.SG_handle == 0) {  in ivtv_udma_alloc()
84 		itv->udma.SG_handle = pci_map_single(itv->pdev, itv->udma.SGarray,  in ivtv_udma_alloc()
85 			   sizeof(itv->udma.SGarray), PCI_DMA_TODEVICE);  in ivtv_udma_alloc()
94 	struct ivtv_user_dma *dma = &itv->udma;  in ivtv_udma_setup()
100 	if (dma->SG_length || dma->page_count) {  in ivtv_udma_setup()
102 			   dma->SG_length, dma->page_count);  in ivtv_udma_setup()
103 		return -EBUSY;  in ivtv_udma_setup()
111 		return -EINVAL;  in ivtv_udma_setup()
116 			dma->map, FOLL_FORCE);  in ivtv_udma_setup()
122 			unpin_user_pages(dma->map, err);  in ivtv_udma_setup()
123 			return -EINVAL;  in ivtv_udma_setup()
128 	dma->page_count = user_dma.page_count;  in ivtv_udma_setup()
132 		unpin_user_pages(dma->map, dma->page_count);  in ivtv_udma_setup()
133 		dma->page_count = 0;  in ivtv_udma_setup()
134 		return -ENOMEM;  in ivtv_udma_setup()
138 	dma->SG_length = pci_map_sg(itv->pdev, dma->SGlist, dma->page_count, PCI_DMA_TODEVICE);  in ivtv_udma_setup()
141 	ivtv_udma_fill_sg_array (dma, ivtv_dest_addr, 0, -1);  in ivtv_udma_setup()
144 	dma->SGarray[dma->SG_length - 1].size |= cpu_to_le32(0x80000000);  in ivtv_udma_setup()
147 	return dma->page_count;  in ivtv_udma_setup()
152 	struct ivtv_user_dma *dma = &itv->udma;  in ivtv_udma_unmap()
157 	if (dma->page_count == 0)  in ivtv_udma_unmap()
161 	if (dma->SG_length) {  in ivtv_udma_unmap()
162 		pci_unmap_sg(itv->pdev, dma->SGlist, dma->page_count, PCI_DMA_TODEVICE);  in ivtv_udma_unmap()
163 		dma->SG_length = 0;  in ivtv_udma_unmap()
168 	unpin_user_pages(dma->map, dma->page_count);  in ivtv_udma_unmap()
169 	dma->page_count = 0;  in ivtv_udma_unmap()
177 	if (itv->udma.SG_handle) {  in ivtv_udma_free()
178 		pci_unmap_single(itv->pdev, itv->udma.SG_handle,  in ivtv_udma_free()
179 			 sizeof(itv->udma.SGarray), PCI_DMA_TODEVICE);  in ivtv_udma_free()
183 	if (itv->udma.SG_length) {  in ivtv_udma_free()
184 		pci_unmap_sg(itv->pdev, itv->udma.SGlist, itv->udma.page_count, PCI_DMA_TODEVICE);  in ivtv_udma_free()
188 		if (itv->udma.bouncemap[i])  in ivtv_udma_free()
189 			__free_page(itv->udma.bouncemap[i]);  in ivtv_udma_free()
195 	IVTV_DEBUG_DMA("start UDMA\n");  in ivtv_udma_start()
196 	write_reg(itv->udma.SG_handle, IVTV_REG_DECDMAADDR);  in ivtv_udma_start()
198 	set_bit(IVTV_F_I_DMA, &itv->i_flags);  in ivtv_udma_start()
199 	set_bit(IVTV_F_I_UDMA, &itv->i_flags);  in ivtv_udma_start()
200 	clear_bit(IVTV_F_I_UDMA_PENDING, &itv->i_flags);  in ivtv_udma_start()
207 	spin_lock_irqsave(&itv->dma_reg_lock, flags);  in ivtv_udma_prepare()
208 	if (!test_bit(IVTV_F_I_DMA, &itv->i_flags))  in ivtv_udma_prepare()
211 		set_bit(IVTV_F_I_UDMA_PENDING, &itv->i_flags);  in ivtv_udma_prepare()
212 	spin_unlock_irqrestore(&itv->dma_reg_lock, flags);  in ivtv_udma_prepare()