V4L/DVB (11320): pxa_camera: Remove YUV planar formats hole
All planes were PAGE aligned (ie. 4096 bytes aligned). This
is not consistent with YUV422 format, which requires Y, U
and V planes glued together. The new implementation forces
the alignement on 8 bytes (DMA requirement), which is almost
always the case (granted by width x height being a multiple
of 8).
The test cases include tests in both YUV422 and RGB565 :
- a picture of size 111 x 111 (cross RAM pages example)
- a picture of size 1023 x 4 in (under 1 RAM page)
- a picture of size 1024 x 4 in (exactly 1 RAM page)
- a picture of size 1025 x 4 in (over 1 RAM page)
- a picture of size 1280 x 1024 (many RAM pages)
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/pxa_camera.c b/drivers/media/video/pxa_camera.c
index 5f57e40..07f792b 100644
--- a/drivers/media/video/pxa_camera.c
+++ b/drivers/media/video/pxa_camera.c
@@ -287,19 +287,63 @@
buf->vb.state = VIDEOBUF_NEEDS_INIT;
}
+static int calculate_dma_sglen(struct scatterlist *sglist, int sglen,
+ int sg_first_ofs, int size)
+{
+ int i, offset, dma_len, xfer_len;
+ struct scatterlist *sg;
+
+ offset = sg_first_ofs;
+ for_each_sg(sglist, sg, sglen, i) {
+ dma_len = sg_dma_len(sg);
+
+ /* PXA27x Developer's Manual 27.4.4.1: round up to 8 bytes */
+ xfer_len = roundup(min(dma_len - offset, size), 8);
+
+ size = max(0, size - xfer_len);
+ offset = 0;
+ if (size == 0)
+ break;
+ }
+
+ BUG_ON(size != 0);
+ return i + 1;
+}
+
+/**
+ * pxa_init_dma_channel - init dma descriptors
+ * @pcdev: pxa camera device
+ * @buf: pxa buffer to find pxa dma channel
+ * @dma: dma video buffer
+ * @channel: dma channel (0 => 'Y', 1 => 'U', 2 => 'V')
+ * @cibr: camera Receive Buffer Register
+ * @size: bytes to transfer
+ * @sg_first: first element of sg_list
+ * @sg_first_ofs: offset in first element of sg_list
+ *
+ * Prepares the pxa dma descriptors to transfer one camera channel.
+ * Beware sg_first and sg_first_ofs are both input and output parameters.
+ *
+ * Returns 0 or -ENOMEM if no coherent memory is available
+ */
static int pxa_init_dma_channel(struct pxa_camera_dev *pcdev,
struct pxa_buffer *buf,
struct videobuf_dmabuf *dma, int channel,
- int sglen, int sg_start, int cibr,
- unsigned int size)
+ int cibr, int size,
+ struct scatterlist **sg_first, int *sg_first_ofs)
{
struct pxa_cam_dma *pxa_dma = &buf->dmas[channel];
- int i;
+ struct scatterlist *sg;
+ int i, offset, sglen;
+ int dma_len = 0, xfer_len = 0;
if (pxa_dma->sg_cpu)
dma_free_coherent(pcdev->dev, pxa_dma->sg_size,
pxa_dma->sg_cpu, pxa_dma->sg_dma);
+ sglen = calculate_dma_sglen(*sg_first, dma->sglen,
+ *sg_first_ofs, size);
+
pxa_dma->sg_size = (sglen + 1) * sizeof(struct pxa_dma_desc);
pxa_dma->sg_cpu = dma_alloc_coherent(pcdev->dev, pxa_dma->sg_size,
&pxa_dma->sg_dma, GFP_KERNEL);
@@ -307,28 +351,54 @@
return -ENOMEM;
pxa_dma->sglen = sglen;
+ offset = *sg_first_ofs;
- for (i = 0; i < sglen; i++) {
- int sg_i = sg_start + i;
- struct scatterlist *sg = dma->sglist;
- unsigned int dma_len = sg_dma_len(&sg[sg_i]), xfer_len;
+ dev_dbg(pcdev->dev, "DMA: sg_first=%p, sglen=%d, ofs=%d, dma.desc=%x\n",
+ *sg_first, sglen, *sg_first_ofs, pxa_dma->sg_dma);
- pxa_dma->sg_cpu[i].dsadr = pcdev->res->start + cibr;
- pxa_dma->sg_cpu[i].dtadr = sg_dma_address(&sg[sg_i]);
+
+ for_each_sg(*sg_first, sg, sglen, i) {
+ dma_len = sg_dma_len(sg);
/* PXA27x Developer's Manual 27.4.4.1: round up to 8 bytes */
- xfer_len = (min(dma_len, size) + 7) & ~7;
+ xfer_len = roundup(min(dma_len - offset, size), 8);
+ size = max(0, size - xfer_len);
+
+ pxa_dma->sg_cpu[i].dsadr = pcdev->res->start + cibr;
+ pxa_dma->sg_cpu[i].dtadr = sg_dma_address(sg) + offset;
pxa_dma->sg_cpu[i].dcmd =
DCMD_FLOWSRC | DCMD_BURST8 | DCMD_INCTRGADDR | xfer_len;
- size -= dma_len;
pxa_dma->sg_cpu[i].ddadr =
pxa_dma->sg_dma + (i + 1) * sizeof(struct pxa_dma_desc);
+
+ dev_vdbg(pcdev->dev, "DMA: desc.%08x->@phys=0x%08x, len=%d\n",
+ pxa_dma->sg_dma + i * sizeof(struct pxa_dma_desc),
+ sg_dma_address(sg) + offset, xfer_len);
+ offset = 0;
+
+ if (size == 0)
+ break;
}
pxa_dma->sg_cpu[sglen - 1].ddadr = DDADR_STOP;
pxa_dma->sg_cpu[sglen - 1].dcmd |= DCMD_ENDIRQEN;
+ /*
+ * Handle 1 special case :
+ * - in 3 planes (YUV422P format), we might finish with xfer_len equal
+ * to dma_len (end on PAGE boundary). In this case, the sg element
+ * for next plane should be the next after the last used to store the
+ * last scatter gather RAM page
+ */
+ if (xfer_len >= dma_len) {
+ *sg_first_ofs = xfer_len - dma_len;
+ *sg_first = sg_next(sg);
+ } else {
+ *sg_first_ofs = xfer_len;
+ *sg_first = sg;
+ }
+
return 0;
}
@@ -340,7 +410,6 @@
struct pxa_camera_dev *pcdev = ici->priv;
struct pxa_buffer *buf = container_of(vb, struct pxa_buffer, vb);
int ret;
- int sglen_y, sglen_yu = 0, sglen_u = 0, sglen_v = 0;
int size_y, size_u = 0, size_v = 0;
dev_dbg(&icd->dev, "%s (vb=0x%p) 0x%08lx %d\n", __func__,
@@ -379,53 +448,51 @@
}
if (vb->state == VIDEOBUF_NEEDS_INIT) {
- unsigned int size = vb->size;
+ int size = vb->size;
+ int next_ofs = 0;
struct videobuf_dmabuf *dma = videobuf_to_dma(vb);
+ struct scatterlist *sg;
ret = videobuf_iolock(vq, vb, NULL);
if (ret)
goto fail;
if (pcdev->channels == 3) {
- /* FIXME the calculations should be more precise */
- sglen_y = dma->sglen / 2;
- sglen_u = sglen_v = dma->sglen / 4 + 1;
- sglen_yu = sglen_y + sglen_u;
size_y = size / 2;
size_u = size_v = size / 4;
} else {
- sglen_y = dma->sglen;
size_y = size;
}
- /* init DMA for Y channel */
- ret = pxa_init_dma_channel(pcdev, buf, dma, 0, sglen_y,
- 0, 0x28, size_y);
+ sg = dma->sglist;
+ /* init DMA for Y channel */
+ ret = pxa_init_dma_channel(pcdev, buf, dma, 0, CIBR0, size_y,
+ &sg, &next_ofs);
if (ret) {
dev_err(pcdev->dev,
"DMA initialization for Y/RGB failed\n");
goto fail;
}
- if (pcdev->channels == 3) {
- /* init DMA for U channel */
- ret = pxa_init_dma_channel(pcdev, buf, dma, 1, sglen_u,
- sglen_y, 0x30, size_u);
- if (ret) {
- dev_err(pcdev->dev,
- "DMA initialization for U failed\n");
- goto fail_u;
- }
+ /* init DMA for U channel */
+ if (size_u)
+ ret = pxa_init_dma_channel(pcdev, buf, dma, 1, CIBR1,
+ size_u, &sg, &next_ofs);
+ if (ret) {
+ dev_err(pcdev->dev,
+ "DMA initialization for U failed\n");
+ goto fail_u;
+ }
- /* init DMA for V channel */
- ret = pxa_init_dma_channel(pcdev, buf, dma, 2, sglen_v,
- sglen_yu, 0x38, size_v);
- if (ret) {
- dev_err(pcdev->dev,
- "DMA initialization for V failed\n");
- goto fail_v;
- }
+ /* init DMA for V channel */
+ if (size_v)
+ ret = pxa_init_dma_channel(pcdev, buf, dma, 2, CIBR2,
+ size_v, &sg, &next_ofs);
+ if (ret) {
+ dev_err(pcdev->dev,
+ "DMA initialization for V failed\n");
+ goto fail_v;
}
vb->state = VIDEOBUF_PREPARED;