Now that the driver has the infrastructure to support more
DMA modes, let's add the DMA scatter-gather mode.
In this mode, the device delivers sequential top-bottom
frames. The scatter-gather logic is based on staging's
tw686x-kh driver (by Krzysztof Hałasa).
Tested-by: Tim Harvey <tharvey@xxxxxxxxxxxxx>
Signed-off-by: Ezequiel Garcia <ezequiel@xxxxxxxxxxxxxxxxxxxx>
---
drivers/media/pci/tw686x/Kconfig | 1 +
drivers/media/pci/tw686x/tw686x-core.c | 4 +
drivers/media/pci/tw686x/tw686x-video.c | 188 ++++++++++++++++++++++++++++++++
drivers/media/pci/tw686x/tw686x.h | 14 +++
4 files changed, 207 insertions(+)
diff --git a/drivers/media/pci/tw686x/Kconfig b/drivers/media/pci/tw686x/Kconfig
index ef8ca85522f8..34ff37712313 100644
--- a/drivers/media/pci/tw686x/Kconfig
+++ b/drivers/media/pci/tw686x/Kconfig
@@ -4,6 +4,7 @@ config VIDEO_TW686X
depends on HAS_DMA
select VIDEOBUF2_VMALLOC
select VIDEOBUF2_DMA_CONTIG
+ select VIDEOBUF2_DMA_SG
select SND_PCM
help
Support for Intersil/Techwell TW686x-based frame grabber cards.
diff --git a/drivers/media/pci/tw686x/tw686x-core.c b/drivers/media/pci/tw686x/tw686x-core.c
index 9a7646c0f9f6..586bc6723c93 100644
--- a/drivers/media/pci/tw686x/tw686x-core.c
+++ b/drivers/media/pci/tw686x/tw686x-core.c
@@ -65,6 +65,8 @@ static const char *dma_mode_name(unsigned int mode)
return "memcpy";
case TW686X_DMA_MODE_CONTIG:
return "contig";
+ case TW686X_DMA_MODE_SG:
+ return "sg";
default:
return "unknown";
}
@@ -81,6 +83,8 @@ static int tw686x_dma_mode_set(const char *val, struct kernel_param *kp)
dma_mode = TW686X_DMA_MODE_MEMCPY;
else if (!strcasecmp(val, dma_mode_name(TW686X_DMA_MODE_CONTIG)))
dma_mode = TW686X_DMA_MODE_CONTIG;
+ else if (!strcasecmp(val, dma_mode_name(TW686X_DMA_MODE_SG)))
+ dma_mode = TW686X_DMA_MODE_SG;
else
return -EINVAL;
return 0;
diff --git a/drivers/media/pci/tw686x/tw686x-video.c b/drivers/media/pci/tw686x/tw686x-video.c
index b5cb385e4cb1..0e839f617e03 100644
--- a/drivers/media/pci/tw686x/tw686x-video.c
+++ b/drivers/media/pci/tw686x/tw686x-video.c
@@ -20,6 +20,7 @@
#include <media/v4l2-common.h>
#include <media/v4l2-event.h>
#include <media/videobuf2-dma-contig.h>
+#include <media/videobuf2-dma-sg.h>
#include <media/videobuf2-vmalloc.h>
#include "tw686x.h"
#include "tw686x-regs.h"
@@ -28,6 +29,10 @@
#define TW686X_VIDEO_WIDTH 720
#define TW686X_VIDEO_HEIGHT(id) ((id & V4L2_STD_525_60) ? 480 : 576)
+#define TW686X_MAX_SG_ENTRY_SIZE 4096
+#define TW686X_MAX_SG_DESC_COUNT 256 /* PAL 720x576 needs 203 4-KB pages */
+#define TW686X_SG_TABLE_SIZE (TW686X_MAX_SG_DESC_COUNT * sizeof(struct tw686x_sg_desc))
+
static const struct tw686x_format formats[] = {
{
.fourcc = V4L2_PIX_FMT_UYVY,
@@ -196,6 +201,174 @@ const struct tw686x_dma_ops contig_dma_ops = {
.field = V4L2_FIELD_INTERLACED,
};
+static int tw686x_sg_desc_fill(struct tw686x_sg_desc *descs,
+ struct tw686x_v4l2_buf *buf,
+ unsigned int buf_len)
+{
+ struct sg_table *vbuf = vb2_dma_sg_plane_desc(&buf->vb.vb2_buf, 0);
+ unsigned int len, entry_len;
+ struct scatterlist *sg;
+ int i, count;
+
+ /* Clear the scatter-gather table */
+ memset(descs, 0, TW686X_SG_TABLE_SIZE);
+
+ count = 0;
+ for_each_sg(vbuf->sgl, sg, vbuf->nents, i) {
+ dma_addr_t phys = sg_dma_address(sg);
+ len = sg_dma_len(sg);
+
+ while (len && buf_len) {
+
+ if (count == TW686X_MAX_SG_DESC_COUNT)
+ return -ENOMEM;
+
+ entry_len = min_t(unsigned int, len,
+ TW686X_MAX_SG_ENTRY_SIZE);
+ entry_len = min_t(unsigned int, entry_len, buf_len);
+ descs[count].phys = cpu_to_le32(phys);
+ descs[count++].flags_length =
+ cpu_to_le32(BIT(30) | entry_len);
+ phys += entry_len;
+ len -= entry_len;
+ buf_len -= entry_len;
+ }
+
+ if (!buf_len)
+ return 0;
+ }
+
+ return -ENOMEM;
+}
+
+static void tw686x_sg_buf_refill(struct tw686x_video_channel *vc,
+ unsigned int pb)
+{
+ struct tw686x_dev *dev = vc->dev;
+ struct tw686x_v4l2_buf *buf;
+
+ while (!list_empty(&vc->vidq_queued)) {
+ unsigned int buf_len;
+
+ buf = list_first_entry(&vc->vidq_queued,
+ struct tw686x_v4l2_buf, list);
+ list_del(&buf->list);
+
+ buf_len = (vc->width * vc->height * vc->format->depth) >> 3;
+ if (tw686x_sg_desc_fill(vc->sg_descs[pb], buf, buf_len)) {
+ v4l2_err(&dev->v4l2_dev,
+ "dma%d: unable to fill %s-buffer\n",
+ vc->ch, pb ? "B" : "P");
+ vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
+ continue;
+ }
+
+ buf->vb.vb2_buf.state = VB2_BUF_STATE_ACTIVE;
+ vc->curr_bufs[pb] = buf;
+ return;
+ }
+
+ vc->curr_bufs[pb] = NULL;
+}
+
+static void tw686x_sg_dma_free(struct tw686x_video_channel *vc,
+ unsigned int pb)
+{
+ struct tw686x_dma_desc *desc = &vc->dma_descs[pb];
+ struct tw686x_dev *dev = vc->dev;
+
+ if (desc->size) {
+ pci_free_consistent(dev->pci_dev, desc->size,
+ desc->virt, desc->phys);
+ desc->virt = NULL;
+ }
+
+ vc->sg_descs[pb] = NULL;
+}
+
+static int tw686x_sg_dma_alloc(struct tw686x_video_channel *vc,
+ unsigned int pb)
+{
+ struct tw686x_dma_desc *desc = &vc->dma_descs[pb];
+ struct tw686x_dev *dev = vc->dev;
+ u32 reg = pb ? DMA_PAGE_TABLE1_ADDR[vc->ch] :
+ DMA_PAGE_TABLE0_ADDR[vc->ch];
+ void *virt;
+
+ if (desc->size) {
+
+ virt = pci_alloc_consistent(dev->pci_dev, desc->size,
+ &desc->phys);
+ if (!virt) {
+ v4l2_err(&dev->v4l2_dev,
+ "dma%d: unable to allocate %s-buffer\n",
+ vc->ch, pb ? "B" : "P");
+ return -ENOMEM;
+ }
+ desc->virt = virt;
+ reg_write(dev, reg, desc->phys);
+ } else {
+ virt = dev->video_channels[0].dma_descs[pb].virt +
+ vc->ch * TW686X_SG_TABLE_SIZE;
+ }
+
+ vc->sg_descs[pb] = virt;
+ return 0;
+}
+
+static void tw686x_sg_cleanup(struct tw686x_dev *dev)
+{
+ vb2_dma_sg_cleanup_ctx(dev->alloc_ctx);
+}
+
+static int tw686x_sg_setup(struct tw686x_dev *dev)
+{
+ unsigned int sg_table_size, pb, ch, channels;
+
+ dev->alloc_ctx = vb2_dma_sg_init_ctx(&dev->pci_dev->dev);
+ if (IS_ERR(dev->alloc_ctx)) {
+ dev_err(&dev->pci_dev->dev, "unable to init DMA context\n");
+ return PTR_ERR(dev->alloc_ctx);
+ }
+
+ if (is_second_gen(dev)) {
+ /*
+ * TW6865/TW6869: each channel needs a pair of
+ * P-B descriptor tables.
+ */
+ channels = max_channels(dev);
+ sg_table_size = TW686X_SG_TABLE_SIZE;
+ } else {
+ /*
+ * TW6864/TW6868: we need to allocate a pair of
+ * P-B descriptor tables, common for all channels.
+ * Each table will be bigger than 4 KB.
+ */
+ channels = 1;
+ sg_table_size = max_channels(dev) * TW686X_SG_TABLE_SIZE;
+ }
+
+ for (ch = 0; ch < channels; ch++) {
+ struct tw686x_video_channel *vc = &dev->video_channels[ch];
+
+ for (pb = 0; pb < 2; pb++)
+ vc->dma_descs[pb].size = sg_table_size;
+ }
+
+ return 0;
+}
+
+const struct tw686x_dma_ops sg_dma_ops = {
+ .setup = tw686x_sg_setup,
+ .cleanup = tw686x_sg_cleanup,
+ .alloc = tw686x_sg_dma_alloc,
+ .free = tw686x_sg_dma_free,
+ .buf_refill = tw686x_sg_buf_refill,
+ .mem_ops = &vb2_dma_sg_memops,
+ .hw_dma_mode = TW686X_SG_MODE,
+ .field = V4L2_FIELD_SEQ_TB,
+};
+
static unsigned int tw686x_fields_map(v4l2_std_id std, unsigned int fps)
{
static const unsigned int map[15] = {
@@ -554,6 +727,19 @@ static int tw686x_s_fmt_vid_cap(struct file *file, void *priv,
else
val &= ~BIT(24);
+ val &= ~0x7ffff;
+
+ /* Program the DMA scatter-gather */
+ if (dev->dma_mode == TW686X_DMA_MODE_SG) {
+ u32 start_idx, end_idx;
+
+ start_idx = is_second_gen(dev) ?
+ 0 : vc->ch * TW686X_MAX_SG_DESC_COUNT;
+ end_idx = start_idx + TW686X_MAX_SG_DESC_COUNT - 1;
+
+ val |= (end_idx << 10) | start_idx;
+ }
+
val &= ~(0x7 << 20);
val |= vc->format->mode << 20;
reg_write(vc->dev, VDMA_CHANNEL_CONFIG[vc->ch], val);
@@ -891,6 +1077,8 @@ int tw686x_video_init(struct tw686x_dev *dev)
dev->dma_ops = &memcpy_dma_ops;
else if (dev->dma_mode == TW686X_DMA_MODE_CONTIG)
dev->dma_ops = &contig_dma_ops;
+ else if (dev->dma_mode == TW686X_DMA_MODE_SG)
+ dev->dma_ops = &sg_dma_ops;
else
return -EINVAL;
diff --git a/drivers/media/pci/tw686x/tw686x.h b/drivers/media/pci/tw686x/tw686x.h
index 5f4c2131ddac..25e3c84331aa 100644
--- a/drivers/media/pci/tw686x/tw686x.h
+++ b/drivers/media/pci/tw686x/tw686x.h
@@ -34,6 +34,7 @@
#define TW686X_DMA_MODE_MEMCPY 0
#define TW686X_DMA_MODE_CONTIG 1
+#define TW686X_DMA_MODE_SG 2
struct tw686x_format {
char *name;
@@ -48,6 +49,12 @@ struct tw686x_dma_desc {
unsigned int size;
};
+struct tw686x_sg_desc {
+ /* 3 MSBits for flags, 13 LSBits for length */
+ __le32 flags_length;
+ __le32 phys;
+};
+
struct tw686x_audio_buf {
dma_addr_t dma;
void *virt;
@@ -80,6 +87,7 @@ struct tw686x_video_channel {
struct video_device *device;
struct tw686x_v4l2_buf *curr_bufs[2];
struct tw686x_dma_desc dma_descs[2];
+ struct tw686x_sg_desc *sg_descs[2];
struct v4l2_ctrl_handler ctrl_handler;
const struct tw686x_format *format;
@@ -154,6 +162,12 @@ static inline unsigned int max_channels(struct tw686x_dev *dev)
return dev->type & TYPE_MAX_CHANNELS; /* 4 or 8 channels */
}
+static inline unsigned is_second_gen(struct tw686x_dev *dev)
+{
+ /* each channel has its own DMA SG table */
+ return dev->type & TYPE_SECOND_GEN;
+}
+
void tw686x_enable_channel(struct tw686x_dev *dev, unsigned int channel);
void tw686x_disable_channel(struct tw686x_dev *dev, unsigned int channel);
--
2.7.0
--
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