[media] tw686x: Add support for DMA scatter-gather mode

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 Ha?asa).

Tested-by: Tim Harvey <tharvey@gateworks.com>
Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
This commit is contained in:
Ezequiel Garcia 2016-06-04 20:47:17 -03:00 committed by Mauro Carvalho Chehab
parent 11a1697404
commit 34e2acc8df
4 changed files with 207 additions and 0 deletions

View file

@ -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.

View file

@ -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;

View file

@ -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;

View file

@ -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);