The core Marvell camera driver can now do scatter/gather DMA on controllers
which support that functionality.
Signed-off-by: Jonathan Corbet <corbet@xxxxxxx>
---
drivers/media/video/marvell-ccic/Kconfig | 3 +
drivers/media/video/marvell-ccic/mcam-core.c | 289 ++++++++++++++++++++++----
drivers/media/video/marvell-ccic/mcam-core.h | 16 ++-
3 files changed, 266 insertions(+), 42 deletions(-)
diff --git a/drivers/media/video/marvell-ccic/Kconfig b/drivers/media/video/marvell-ccic/Kconfig
index 22314a0..5be66e2 100644
--- a/drivers/media/video/marvell-ccic/Kconfig
+++ b/drivers/media/video/marvell-ccic/Kconfig
@@ -3,6 +3,8 @@ config VIDEO_CAFE_CCIC
depends on PCI && I2C && VIDEO_V4L2
select VIDEO_OV7670
select VIDEOBUF2_VMALLOC
+ select VIDEOBUF2_DMA_CONTIG
+ select VIDEOBUF2_DMA_SG
---help---
This is a video4linux2 driver for the Marvell 88ALP01 integrated
CMOS camera controller. This is the controller found on first-
@@ -15,6 +17,7 @@ config VIDEO_MMP_CAMERA
select I2C_GPIO
select VIDEOBUF2_VMALLOC
select VIDEOBUF2_DMA_CONTIG
+ select VIDEOBUF2_DMA_SG
---help---
This is a Video4Linux2 driver for the integrated camera
controller found on Marvell Armada 610 application
diff --git a/drivers/media/video/marvell-ccic/mcam-core.c b/drivers/media/video/marvell-ccic/mcam-core.c
index 419b4e5..af5faa6 100644
--- a/drivers/media/video/marvell-ccic/mcam-core.c
+++ b/drivers/media/video/marvell-ccic/mcam-core.c
@@ -26,6 +26,7 @@
#include <media/ov7670.h>
#include <media/videobuf2-vmalloc.h>
#include <media/videobuf2-dma-contig.h>
+#include <media/videobuf2-dma-sg.h>
#include "mcam-core.h"
@@ -106,6 +107,7 @@ MODULE_PARM_DESC(buffer_mode,
#define CF_DMA_ACTIVE 3 /* A frame is incoming */
#define CF_CONFIG_NEEDED 4 /* Must configure hardware */
#define CF_SINGLE_BUFFER 5 /* Running with a single buffer */
+#define CF_SG_RESTART 6 /* SG restart needed */
#define sensor_call(cam, o, f, args...) \
v4l2_subdev_call(cam->sensor, o, f, ##args)
@@ -180,6 +182,17 @@ static void mcam_set_config_needed(struct mcam_camera *cam, int needed)
}
/*
+ * The two-word DMA descriptor format used by the Armada 610 and like. There
+ * Is a three-word format as well (set C1_DESC_3WORD) where the third
+ * word is a pointer to the next descriptor, but we don't use it. Two-word
+ * descriptors have to be contiguous in memory.
+ */
+struct mcam_dma_desc {
+ u32 dma_addr;
+ u32 segment_len;
+};
+
+/*
* Our buffer type for working with videobuf2. Note that the vb2
* developers have decreed that struct vb2_buffer must be at the
* beginning of this structure.
@@ -187,6 +200,9 @@ static void mcam_set_config_needed(struct mcam_camera *cam, int needed)
struct mcam_vb_buffer {
struct vb2_buffer vb_buf;
struct list_head queue;
+ struct mcam_dma_desc *dma_desc; /* Descriptor virtual address */
+ dma_addr_t dma_desc_pa; /* Descriptor physical address */
+ int dma_desc_nent; /* Number of mapped descriptors */
};
static inline struct mcam_vb_buffer *vb_to_mvb(struct vb2_buffer *vb)
@@ -268,6 +284,9 @@ static void mcam_set_contig_buffer(struct mcam_camera *cam, int frame)
clear_bit(CF_SINGLE_BUFFER, &cam->flags);
}
+/*
+ * Initial B_DMA_contig setup.
+ */
static void mcam_ctlr_dma_contig(struct mcam_camera *cam)
{
mcam_reg_set_bit(cam, REG_CTRL1, C1_TWOBUFS);
@@ -277,14 +296,38 @@ static void mcam_ctlr_dma_contig(struct mcam_camera *cam)
}
-static void mcam_ctlr_dma(struct mcam_camera *cam)
+/*
+ * Set up the next buffer for S/G I/O; caller should be sure that
+ * the controller is stopped and a buffer is available.
+ */
+static void mcam_sg_next_buffer(struct mcam_camera *cam)
{
- if (cam->buffer_mode == B_DMA_contig)
- mcam_ctlr_dma_contig(cam);
- else
- mcam_ctlr_dma_vmalloc(cam);
+ struct mcam_vb_buffer *buf;
+
+ buf = list_first_entry(&cam->buffers, struct mcam_vb_buffer, queue);
+ list_del_init(&buf->queue);
+ mcam_reg_write(cam, REG_DMA_DESC_Y, buf->dma_desc_pa);
+ mcam_reg_write(cam, REG_DESC_LEN_Y,
+ buf->dma_desc_nent*sizeof(struct mcam_dma_desc));
+ mcam_reg_write(cam, REG_DESC_LEN_U, 0);
+ mcam_reg_write(cam, REG_DESC_LEN_V, 0);
+ cam->vb_bufs[0] = buf;
}
+/*
+ * Initial B_DMA_sg setup
+ */
+static void mcam_ctlr_dma_sg(struct mcam_camera *cam)
+{
+ mcam_reg_clear_bit(cam, REG_CTRL1, C1_DESC_3WORD);
+ mcam_sg_next_buffer(cam);
+ mcam_reg_set_bit(cam, REG_CTRL1, C1_DESC_ENA);
+ cam->nbufs = 3;
+}
+
+/*
+ * Image format setup, independent of DMA scheme.
+ */
static void mcam_ctlr_image(struct mcam_camera *cam)
{
int imgsz;
@@ -341,9 +384,20 @@ static int mcam_ctlr_configure(struct mcam_camera *cam)
unsigned long flags;
spin_lock_irqsave(&cam->dev_lock, flags);
- mcam_ctlr_dma(cam);
+ switch (cam->buffer_mode) {
+ case B_vmalloc:
+ mcam_ctlr_dma_vmalloc(cam);
+ break;
+ case B_DMA_contig:
+ mcam_ctlr_dma_contig(cam);
+ break;
+ case B_DMA_sg:
+ mcam_ctlr_dma_sg(cam);
+ break;
+ }
mcam_ctlr_image(cam);
mcam_set_config_needed(cam, 0);
+ clear_bit(CF_SG_RESTART, &cam->flags);
spin_unlock_irqrestore(&cam->dev_lock, flags);
return 0;
}
@@ -379,6 +433,19 @@ static void mcam_ctlr_stop(struct mcam_camera *cam)
mcam_reg_clear_bit(cam, REG_CTRL0, C0_ENABLE);
}
+/*
+ * Scatter/gather mode requires stopping the controller between
+ * frames so we can put in a new DMA descriptor array. If no new
+ * buffer exists at frame completion, the controller is left stopped;
+ * this function is charged with gettig things going again.
+ */
+static void mcam_sg_restart(struct mcam_camera *cam)
+{
+ mcam_ctlr_dma_sg(cam);
+ mcam_ctlr_start(cam);
+ clear_bit(CF_SG_RESTART, &cam->flags);
+}
+
static void mcam_ctlr_init(struct mcam_camera *cam)
{
unsigned long flags;
@@ -416,14 +483,15 @@ static void mcam_ctlr_stop_dma(struct mcam_camera *cam)
* interrupt, then wait until no DMA is active.
*/
spin_lock_irqsave(&cam->dev_lock, flags);
+ clear_bit(CF_SG_RESTART, &cam->flags);
mcam_ctlr_stop(cam);
+ cam->state = S_IDLE;
spin_unlock_irqrestore(&cam->dev_lock, flags);
- msleep(10);
+ msleep(40);
if (test_bit(CF_DMA_ACTIVE, &cam->flags))
cam_err(cam, "Timeout waiting for DMA to end\n");
/* This would be bad news - what now? */
spin_lock_irqsave(&cam->dev_lock, flags);
- cam->state = S_IDLE;
mcam_ctlr_irq_disable(cam);
spin_unlock_irqrestore(&cam->dev_lock, flags);
}
@@ -540,9 +608,8 @@ static int mcam_cam_configure(struct mcam_camera *cam)
* DMA buffer management. These functions need s_mutex held.
*/
-/* FIXME: this is inefficient as hell, since dma_alloc_coherent just
- * does a get_free_pages() call, and we waste a good chunk of an orderN
- * allocation. Should try to allocate the whole set in one chunk.
+/*
+ * Allocate in-kernel DMA buffers for vmalloc mode.
*/
static int mcam_alloc_dma_bufs(struct mcam_camera *cam, int loadtime)
{
@@ -650,24 +717,56 @@ static int mcam_vb_queue_setup(struct vb2_queue *vq, unsigned int *nbufs,
void *alloc_ctxs[])
{
struct mcam_camera *cam = vb2_get_drv_priv(vq);
+ int minbufs = (cam->buffer_mode == B_DMA_contig) ? 3 : 2;
sizes[0] = cam->pix_format.sizeimage;
*num_planes = 1; /* Someday we have to support planar formats... */
- if (*nbufs < 3 || *nbufs > 32)
- *nbufs = 3; /* semi-arbitrary numbers */
+ if (*nbufs < minbufs)
+ *nbufs = minbufs;
if (cam->buffer_mode == B_DMA_contig)
alloc_ctxs[0] = cam->vb_alloc_ctx;
return 0;
}
-static int mcam_vb_buf_init(struct vb2_buffer *vb)
+/* DMA_sg only */
+static int mcam_vb_sg_buf_init(struct vb2_buffer *vb)
+{
+ struct mcam_vb_buffer *mvb = vb_to_mvb(vb);
+ struct mcam_camera *cam = vb2_get_drv_priv(vb->vb2_queue);
+ int ndesc = cam->pix_format.sizeimage/PAGE_SIZE + 1;
+
+ mvb->dma_desc = dma_alloc_coherent(cam->dev,
+ ndesc * sizeof(struct mcam_dma_desc),
+ &mvb->dma_desc_pa, GFP_KERNEL);
+ if (mvb->dma_desc == NULL) {
+ cam_err(cam, "Unable to get DMA descriptor array\n");
+ return -ENOMEM;
+ }
+ return 0;
+}
+
+static int mcam_vb_sg_buf_prepare(struct vb2_buffer *vb)
{
struct mcam_vb_buffer *mvb = vb_to_mvb(vb);
+ struct mcam_camera *cam = vb2_get_drv_priv(vb->vb2_queue);
+ struct vb2_dma_sg_desc *sgd = vb2_dma_sg_plane_desc(vb, 0);
+ struct mcam_dma_desc *desc = mvb->dma_desc;
+ struct scatterlist *sg;
+ int i;
- INIT_LIST_HEAD(&mvb->queue);
+ mvb->dma_desc_nent = dma_map_sg(cam->dev, sgd->sglist, sgd->num_pages,
+ DMA_FROM_DEVICE);
+ if (mvb->dma_desc_nent <= 0)
+ return -EIO; /* Not sure what's right here */
+ for_each_sg(sgd->sglist, sg, mvb->dma_desc_nent, i) {
+ desc->dma_addr = sg_dma_address(sg);
+ desc->segment_len = sg_dma_len(sg);
+ desc++;
+ }
return 0;
}
+
static void mcam_vb_buf_queue(struct vb2_buffer *vb)
{
struct mcam_vb_buffer *mvb = vb_to_mvb(vb);
@@ -678,11 +777,34 @@ static void mcam_vb_buf_queue(struct vb2_buffer *vb)
spin_lock_irqsave(&cam->dev_lock, flags);
start = (cam->state == S_BUFWAIT) && !list_empty(&cam->buffers);
list_add(&mvb->queue, &cam->buffers);
+ if (test_bit(CF_SG_RESTART, &cam->flags))
+ mcam_sg_restart(cam);
spin_unlock_irqrestore(&cam->dev_lock, flags);
if (start)
mcam_read_setup(cam);
}
+
+static int mcam_vb_sg_buf_finish(struct vb2_buffer *vb)
+{
+ struct mcam_camera *cam = vb2_get_drv_priv(vb->vb2_queue);
+ struct vb2_dma_sg_desc *sgd = vb2_dma_sg_plane_desc(vb, 0);
+
+ dma_unmap_sg(cam->dev, sgd->sglist, sgd->num_pages, DMA_FROM_DEVICE);
+ return 0;
+}
+
+static void mcam_vb_sg_buf_cleanup(struct vb2_buffer *vb)
+{
+ struct mcam_camera *cam = vb2_get_drv_priv(vb->vb2_queue);
+ struct mcam_vb_buffer *mvb = vb_to_mvb(vb);
+ int ndesc = cam->pix_format.sizeimage/PAGE_SIZE + 1;
+
+ dma_free_coherent(cam->dev, ndesc * sizeof(struct mcam_dma_desc),
+ mvb->dma_desc, mvb->dma_desc_pa);
+}
+
+
/*
* vb2 uses these to release the mutex when waiting in dqbuf. I'm
* not actually sure we need to do this (I'm not sure that vb2_dqbuf() needs
@@ -752,7 +874,6 @@ static int mcam_vb_stop_streaming(struct vb2_queue *vq)
static const struct vb2_ops mcam_vb2_ops = {
.queue_setup = mcam_vb_queue_setup,
- .buf_init = mcam_vb_buf_init,
.buf_queue = mcam_vb_buf_queue,
.start_streaming = mcam_vb_start_streaming,
.stop_streaming = mcam_vb_stop_streaming,
@@ -760,22 +881,49 @@ static const struct vb2_ops mcam_vb2_ops = {
.wait_finish = mcam_vb_wait_finish,
};
+/*
+ * Scatter/gather mode complicates things somewhat.
+ */
+static const struct vb2_ops mcam_vb2_sg_ops = {
+ .queue_setup = mcam_vb_queue_setup,
+ .buf_init = mcam_vb_sg_buf_init,
+ .buf_prepare = mcam_vb_sg_buf_prepare,
+ .buf_queue = mcam_vb_buf_queue,
+ .buf_finish = mcam_vb_sg_buf_finish,
+ .buf_cleanup = mcam_vb_sg_buf_cleanup,
+ .start_streaming = mcam_vb_start_streaming,
+ .stop_streaming = mcam_vb_stop_streaming,
+ .wait_prepare = mcam_vb_wait_prepare,
+ .wait_finish = mcam_vb_wait_finish,
+};
+
static int mcam_setup_vb2(struct mcam_camera *cam)
{
struct vb2_queue *vq = &cam->vb_queue;
memset(vq, 0, sizeof(*vq));
vq->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
- vq->io_modes = VB2_MMAP; /* Add userptr */
vq->drv_priv = cam;
- vq->ops = &mcam_vb2_ops;
- if (cam->buffer_mode == B_DMA_contig) {
+ INIT_LIST_HEAD(&cam->buffers);
+ switch (cam->buffer_mode) {
+ case B_DMA_contig:
+ vq->ops = &mcam_vb2_ops;
vq->mem_ops = &vb2_dma_contig_memops;
cam->vb_alloc_ctx = vb2_dma_contig_init_ctx(cam->dev);
- } else
+ vq->io_modes = VB2_MMAP | VB2_USERPTR;
+ break;
+ case B_DMA_sg:
+ vq->ops = &mcam_vb2_sg_ops;
+ vq->mem_ops = &vb2_dma_sg_memops;
+ vq->io_modes = VB2_MMAP | VB2_USERPTR;
+ break;
+ case B_vmalloc:
+ vq->ops = &mcam_vb2_ops;
vq->mem_ops = &vb2_vmalloc_memops;
- vq->buf_struct_size = sizeof(struct mcam_vb_buffer);
-
+ vq->buf_struct_size = sizeof(struct mcam_vb_buffer);
+ vq->io_modes = VB2_MMAP;
+ break;
+ }
return vb2_queue_init(vq);
}
@@ -1313,8 +1461,6 @@ static void mcam_buffer_done(struct mcam_camera *cam, int frame,
{
vbuf->v4l2_buf.bytesused = cam->pix_format.sizeimage;
vbuf->v4l2_buf.sequence = cam->buf_seq[frame];
- vbuf->v4l2_buf.flags &= ~V4L2_BUF_FLAG_QUEUED;
- vbuf->v4l2_buf.flags |= V4L2_BUF_FLAG_DONE;
vb2_set_plane_payload(vbuf, 0, cam->pix_format.sizeimage);
vb2_buffer_done(vbuf, VB2_BUF_STATE_DONE);
}
@@ -1363,7 +1509,7 @@ static void mcam_frame_tasklet(unsigned long data)
/*
* For direct DMA, mark the buffer ready and set up another one.
*/
-static void mcam_dma_complete(struct mcam_camera *cam, int frame)
+static void mcam_dma_contig_done(struct mcam_camera *cam, int frame)
{
struct mcam_vb_buffer *buf = cam->vb_bufs[frame];
@@ -1374,6 +1520,52 @@ static void mcam_dma_complete(struct mcam_camera *cam, int frame)
mcam_set_contig_buffer(cam, frame);
}
+/*
+ * Frame completion with S/G is trickier. We can't muck with
+ * a descriptor chain on the fly, since the controller buffers it
+ * internally. So we have to actually stop and restart; Marvell
+ * says this is the way to do it.
+ *
+ * Of course, stopping is easier said than done; experience shows
+ * that the controller can start a frame *after* C0_ENABLE has been
+ * cleared. So when running in S/G mode, the controller is "stopped"
+ * on receipt of the start-of-frame interrupt. That means we can
+ * safely change the DMA descriptor array here and restart things
+ * (assuming there's another buffer waiting to go).
+ */
+static void mcam_dma_sg_done(struct mcam_camera *cam, int frame)
+{
+ struct mcam_vb_buffer *buf = cam->vb_bufs[0];
+
+ /*
+ * Very Bad Not Good Things happen if you don't clear
+ * C1_DESC_ENA before making any descriptor changes.
+ */
+ mcam_reg_clear_bit(cam, REG_CTRL1, C1_DESC_ENA);
+ /*
+ * If we have another buffer available, put it in and
+ * restart the engine.
+ */
+ if (!list_empty(&cam->buffers)) {
+ mcam_sg_next_buffer(cam);
+ mcam_reg_set_bit(cam, REG_CTRL1, C1_DESC_ENA);
+ mcam_ctlr_start(cam);
+ /*
+ * Otherwise set CF_SG_RESTART and the controller will
+ * be restarted once another buffer shows up.
+ */
+ } else {
+ set_bit(CF_SG_RESTART, &cam->flags);
+ singles++;
+ }
+ /*
+ * Now we can give the completed frame back to user space.
+ */
+ delivered++;
+ mcam_buffer_done(cam, frame, &buf->vb_buf);
+}
+
+
static void mcam_frame_complete(struct mcam_camera *cam, int frame)
{
@@ -1385,22 +1577,25 @@ static void mcam_frame_complete(struct mcam_camera *cam, int frame)
cam->next_buf = frame;
cam->buf_seq[frame] = ++(cam->sequence);
cam->last_delivered = frame;
-
frames++;
- switch (cam->state) {
/*
- * We're streaming and have a ready frame, hand it back
+ * "This should never happen"
*/
- case S_STREAMING:
- if (cam->buffer_mode == B_vmalloc)
- tasklet_schedule(&cam->s_tasklet);
- else
- mcam_dma_complete(cam, frame);
- break;
-
- default:
- cam_err(cam, "Frame interrupt in non-operational state\n");
- break;
+ if (cam->state != S_STREAMING)
+ return;
+ /*
+ * Process the frame and set up the next one.
+ */
+ switch (cam->buffer_mode) {
+ case B_vmalloc:
+ tasklet_schedule(&cam->s_tasklet);
+ break;
+ case B_DMA_contig:
+ mcam_dma_contig_done(cam, frame);
+ break;
+ case B_DMA_sg:
+ mcam_dma_sg_done(cam, frame);
+ break;
}
}
@@ -1416,6 +1611,11 @@ int mccic_irq(struct mcam_camera *cam, unsigned int irqs)
* Handle any frame completions. There really should
* not be more than one of these, or we have fallen
* far behind.
+ *
+ * When running in S/G mode, the frame number lacks any
+ * real meaning - there's only one descriptor array - but
+ * the controller still picks a different one to signal
+ * each time.
*/
for (frame = 0; frame < cam->nbufs; frame++)
if (irqs & (IRQ_EOF0 << frame)) {
@@ -1430,6 +1630,8 @@ int mccic_irq(struct mcam_camera *cam, unsigned int irqs)
if (irqs & (IRQ_SOF0 | IRQ_SOF1 | IRQ_SOF2)) {
set_bit(CF_DMA_ACTIVE, &cam->flags);
handled = 1;
+ if (cam->buffer_mode == B_DMA_sg)
+ mcam_ctlr_stop(cam);
}
return handled;
}
@@ -1480,8 +1682,15 @@ int mccic_register(struct mcam_camera *cam)
cam->buffer_mode = B_vmalloc;
else if (buffer_mode == 1)
cam->buffer_mode = B_DMA_contig;
- else if (buffer_mode != -1)
- printk(KERN_ERR "marvel-cam: "
+ else if (buffer_mode == 2) {
+ if (cam->chip_id == V4L2_IDENT_ARMADA610)
+ cam->buffer_mode = B_DMA_sg;
+ else {
+ printk(KERN_ERR "marvell-cam: Cafe can't do S/G I/O\n");
+ cam->buffer_mode = B_vmalloc;
+ }
+ } else if (buffer_mode != -1)
+ printk(KERN_ERR "marvell-cam: "
"Strange module buffer mode %d - ignoring\n",
buffer_mode);
mcam_ctlr_init(cam);
diff --git a/drivers/media/video/marvell-ccic/mcam-core.h b/drivers/media/video/marvell-ccic/mcam-core.h
index 2e667a0..55fd078 100644
--- a/drivers/media/video/marvell-ccic/mcam-core.h
+++ b/drivers/media/video/marvell-ccic/mcam-core.h
@@ -38,7 +38,8 @@ enum mcam_state {
*/
enum mcam_buffer_mode {
B_vmalloc = 0,
- B_DMA_contig
+ B_DMA_contig,
+ B_DMA_sg
};
/*
@@ -250,8 +251,11 @@ int mccic_resume(struct mcam_camera *cam);
#define C0_SIF_HVSYNC 0x00000000 /* Use H/VSYNC */
#define CO_SOF_NOSYNC 0x40000000 /* Use inband active signaling */
-
+/* Bits below C1_444ALPHA are not present in Cafe */
#define REG_CTRL1 0x40 /* Control 1 */
+#define C1_CLKGATE 0x00000001 /* Sensor clock gate */
+#define C1_DESC_ENA 0x00000100 /* DMA descriptor enable */
+#define C1_DESC_3WORD 0x00000200 /* Three-word descriptors used */
#define C1_444ALPHA 0x00f00000 /* Alpha field in RGB444 */
#define C1_ALPHA_SHFT 20
#define C1_DMAB32 0x00000000 /* 32-byte DMA burst */
@@ -267,6 +271,14 @@ int mccic_resume(struct mcam_camera *cam);
/* This appears to be a Cafe-only register */
#define REG_UBAR 0xc4 /* Upper base address register */
+/* Armada 610 DMA descriptor registers */
+#define REG_DMA_DESC_Y 0x200
+#define REG_DMA_DESC_U 0x204
+#define REG_DMA_DESC_V 0x208
+#define REG_DESC_LEN_Y 0x20c /* Lengths are in bytes */
+#define REG_DESC_LEN_U 0x210
+#define REG_DESC_LEN_V 0x214
+
/*
* Useful stuff that probably belongs somewhere global.
*/
--
1.7.5.4
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