Re: [PATCH v3 5/7] media: aspeed: Support aspeed mode to reduce compressed data

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Dear Hans,

On 2021/11/9 下午 06:17, Hans Verkuil wrote:
On 11/9/21 2:56 AM, Jammy Huang wrote:
Dear Hans,

Thanks for your review.

On 2021/11/8 下午 05:09, Hans Verkuil wrote:
On 22/10/2021 08:55, Jammy Huang wrote:
aspeed supports differential jpeg format which only compress the parts
which are changed. In this way, it reduces both the amount of data to be
transferred by network and those to be decoded on the client side.

4 new ctrls are added:
* Aspeed JPEG Format: to control aspeed's partial jpeg on/off
    0: standard jpeg, 1: aspeed jpeg
What exactly is 'aspeed jpeg'?
'aspeed jpeg' is aspeed proprietary compression format. It will compare
the new frame
with previous one to decide which macroblock's data is changed, and only
the changed
macroblock will be compressed. In this way, the amount of compressed data is
significantly reduced. This is similar to the concept of I/P-frames of
video compression.
Right, but that makes this a new vendor-specific pixelformat, not a control.
OK, I will add a new vendor-specific pixelformat for this.

For example, the video is static in first 3 frames and then a object in
the video moved in
4th frame.

          Frame Content      |    Standard    |    Aspeed
-----------------------------------------------------------------------
1th                                 |    Full             | Full
2th    identical with 1st   |    Full             |   none (only about
12 Bytes for header data)
3th    identical with 1st   |    Full             |   none
4th    a object moved     |    Full             |   Only the Macroblocks
that have data changed are compressed

I have implemented a javascript aspeed decoder in novnc to support this
format, but
the performance isn't good enough. I am working on a web-assembly to
improve it.
Is this format documented in a datasheet or something similar, ideally freely
available?
This format is documented in ast2400/2500/2600's datasheet, but it's not freely available.

* Aspeed Compression Mode: to control aspeed's compression mode
    0: DCT Only, 1: DCT VQ mix 2-color, 2: DCT VQ mix 4-color
    This is AST2400 only. It will adapt JPEG or VQ encoding method according
    to the context automatically.
What exactly does this do?

Is this very aspeed-specific, or could this be a standard JPEG control?
Yes, this is aspeed-specific. Its compression algorithm is a modified
JPEG algorithm.
Is this specific to the aspeed jpeg format, or also to the 'regular' jpeg format?

It's specific to the aspeed jpeg format. Regular jpeg is based on DCT and doesn't support VQ
compression


Regards,

	Hans

* Aspeed HQ Mode: to control aspeed's HQ mode on/off
    0: disabled, 1: enabled
* Aspeed HQ Quality: to control the quality of aspeed's HQ mode
    only useful if Aspeed HQ mode is enabled
Can these two controls be replaced by the existing V4L2_CID_JPEG_COMPRESSION_QUALITY
control? I.e.: range 1..12 is non-HQ, 13-24 is HQ. Note that the spec recommends
that value 0 is not used in the V4L2_CID_JPEG_COMPRESSION_QUALITY range:

https://hverkuil.home.xs4all.nl/spec/userspace-api/v4l/ext-ctrls-jpeg.html
HQ mode is aspeed-specific and not related to stanard jpeg's compression
quality. These two
quality attribute can be controlled independently. So, I think it is not
proper to integrate them
together.

Noted, I will modified the min value of these 2 quality control.

Aspeed JPEG Format requires an additional buffer, called bcd, to store
the information about which macro block in the new frame is different
from the previous one.

To have bcd correctly working, we need to swap the buffers for src0/1 to
make src1 refer to previous frame and src0 to the coming new frame.

Signed-off-by: Jammy Huang <jammy_huang@xxxxxxxxxxxxxx>
---
   drivers/media/platform/aspeed-video.c | 222 +++++++++++++++++++++++---
   1 file changed, 203 insertions(+), 19 deletions(-)

diff --git a/drivers/media/platform/aspeed-video.c b/drivers/media/platform/aspeed-video.c
index cafbffe1ef69..94d17dee6f3d 100644
--- a/drivers/media/platform/aspeed-video.c
+++ b/drivers/media/platform/aspeed-video.c
@@ -32,6 +32,12 @@
   #include <media/videobuf2-dma-contig.h>
   #include <linux/videodev2.h>
+#define ASPEED_CID_CUSTOM_BASE (V4L2_CID_USER_BASE | 0xf000)
Driver-specific control ID ranges must be reserved in include/uapi/linux/v4l2-controls.h.
See e.g. V4L2_CID_USER_ALLEGRO_BASE.
OKay, I will update in the next patch.
Regards,

	Hans

+#define V4L2_CID_ASPEED_FORMAT			(ASPEED_CID_CUSTOM_BASE  + 1)
+#define V4L2_CID_ASPEED_COMPRESSION_MODE	(ASPEED_CID_CUSTOM_BASE  + 2)
+#define V4L2_CID_ASPEED_HQ_MODE			(ASPEED_CID_CUSTOM_BASE  + 3)
+#define V4L2_CID_ASPEED_HQ_JPEG_QUALITY		(ASPEED_CID_CUSTOM_BASE  + 4)
+
   #define DEVICE_NAME			"aspeed-video"
#define ASPEED_VIDEO_JPEG_NUM_QUALITIES 12
@@ -55,6 +61,7 @@
#define VE_MAX_SRC_BUFFER_SIZE 0x8ca000 /* 1920 * 1200, 32bpp */
   #define VE_JPEG_HEADER_SIZE		0x006000 /* 512 * 12 * 4 */
+#define VE_BCD_BUFF_SIZE		0x100000
#define VE_PROTECTION_KEY 0x000
   #define  VE_PROTECTION_KEY_UNLOCK	0x1a038aa8
@@ -108,6 +115,13 @@
   #define VE_SCALING_FILTER2		0x020
   #define VE_SCALING_FILTER3		0x024
+#define VE_BCD_CTRL 0x02C
+#define  VE_BCD_CTRL_EN_BCD		BIT(0)
+#define  VE_BCD_CTRL_EN_ABCD		BIT(1)
+#define  VE_BCD_CTRL_EN_CB		BIT(2)
+#define  VE_BCD_CTRL_THR		GENMASK(23, 16)
+#define  VE_BCD_CTRL_ABCD_THR		GENMASK(31, 24)
+
   #define VE_CAP_WINDOW			0x030
   #define VE_COMP_WINDOW			0x034
   #define VE_COMP_PROC_OFFSET		0x038
@@ -116,6 +130,7 @@
   #define VE_SRC0_ADDR			0x044
   #define VE_SRC_SCANLINE_OFFSET		0x048
   #define VE_SRC1_ADDR			0x04c
+#define VE_BCD_ADDR			0x050
   #define VE_COMP_ADDR			0x054
#define VE_STREAM_BUF_SIZE 0x058
@@ -136,6 +151,8 @@
   #define  VE_COMP_CTRL_HQ_DCT_CHR	GENMASK(26, 22)
   #define  VE_COMP_CTRL_HQ_DCT_LUM	GENMASK(31, 27)
+#define VE_CB_ADDR 0x06C
+
   #define VE_OFFSET_COMP_STREAM		0x078
#define VE_JPEG_COMP_SIZE_READ_BACK 0x084
@@ -243,10 +260,15 @@ struct aspeed_video {
   	unsigned int max_compressed_size;
   	struct aspeed_video_addr srcs[2];
   	struct aspeed_video_addr jpeg;
+	struct aspeed_video_addr bcd;
bool yuv420;
+	bool partial_jpeg;
+	bool hq_mode;
   	unsigned int frame_rate;
   	unsigned int jpeg_quality;
+	unsigned int jpeg_hq_quality;
+	unsigned int compression_mode;
unsigned int frame_bottom;
   	unsigned int frame_left;
@@ -258,6 +280,13 @@ struct aspeed_video {
#define to_aspeed_video(x) container_of((x), struct aspeed_video, v4l2_dev) +static bool aspeed_video_alloc_buf(struct aspeed_video *video,
+				   struct aspeed_video_addr *addr,
+				   unsigned int size);
+
+static void aspeed_video_free_buf(struct aspeed_video *video,
+				  struct aspeed_video_addr *addr);
+
   static const u32 aspeed_video_jpeg_header[ASPEED_VIDEO_JPEG_HEADER_SIZE] = {
   	0xe0ffd8ff, 0x464a1000, 0x01004649, 0x60000101, 0x00006000, 0x0f00feff,
   	0x00002d05, 0x00000000, 0x00000000, 0x00dbff00
@@ -492,6 +521,20 @@ static int aspeed_video_start_frame(struct aspeed_video *video)
   		return -EBUSY;
   	}
+ if (video->partial_jpeg && !video->bcd.size) {
+		if (!aspeed_video_alloc_buf(video, &video->bcd,
+					    VE_BCD_BUFF_SIZE)) {
+			dev_err(video->dev, "Failed to allocate BCD buffer\n");
+			dev_err(video->dev, "don't start frame\n");
+			return -ENOMEM;
+		}
+		aspeed_video_write(video, VE_BCD_ADDR, video->bcd.dma);
+		v4l2_dbg(1, debug, &video->v4l2_dev, "bcd addr(%#x) size(%d)\n",
+			video->bcd.dma, video->bcd.size);
+	} else if (!video->partial_jpeg && video->bcd.size) {
+		aspeed_video_free_buf(video, &video->bcd);
+	}
+
   	spin_lock_irqsave(&video->lock, flags);
   	buf = list_first_entry_or_null(&video->buffers,
   				       struct aspeed_video_buffer, link);
@@ -635,6 +678,7 @@ static irqreturn_t aspeed_video_irq(int irq, void *arg)
if (sts & VE_INTERRUPT_COMP_COMPLETE) {
   		struct aspeed_video_buffer *buf;
+		bool empty = true;
   		u32 frame_size = aspeed_video_read(video,
   						   VE_JPEG_COMP_SIZE_READ_BACK);
@@ -648,13 +692,23 @@ static irqreturn_t aspeed_video_irq(int irq, void *arg)
   		if (buf) {
   			vb2_set_plane_payload(&buf->vb.vb2_buf, 0, frame_size);
- if (!list_is_last(&buf->link, &video->buffers)) {
+			/*
+			 * partial_jpeg requires continuous update.
+			 * On the contrary, standard jpeg can keep last buffer
+			 * to always have the latest result.
+			 */
+			if (!video->partial_jpeg &&
+			    list_is_last(&buf->link, &video->buffers)) {
+				empty = false;
+				v4l2_warn(&video->v4l2_dev, "skip to keep last frame updated\n");
+			} else {
   				buf->vb.vb2_buf.timestamp = ktime_get_ns();
   				buf->vb.sequence = video->sequence++;
   				buf->vb.field = V4L2_FIELD_NONE;
   				vb2_buffer_done(&buf->vb.vb2_buf,
   						VB2_BUF_STATE_DONE);
   				list_del(&buf->link);
+				empty = list_empty(&video->buffers);
   			}
   		}
   		spin_unlock(&video->lock);
@@ -668,7 +722,18 @@ static irqreturn_t aspeed_video_irq(int irq, void *arg)
   		aspeed_video_write(video, VE_INTERRUPT_STATUS,
   				   VE_INTERRUPT_COMP_COMPLETE);
   		sts &= ~VE_INTERRUPT_COMP_COMPLETE;
-		if (test_bit(VIDEO_STREAMING, &video->flags) && buf)
+
+		// swap src buffer if partial_jpeg
+		if (video->partial_jpeg) {
+			u32 src0, src1;
+
+			src0 = aspeed_video_read(video, VE_SRC0_ADDR);
+			src1 = aspeed_video_read(video, VE_SRC1_ADDR);
+			aspeed_video_write(video, VE_SRC0_ADDR, src1);
+			aspeed_video_write(video, VE_SRC1_ADDR, src0);
+		}
+
+		if (test_bit(VIDEO_STREAMING, &video->flags) && !empty)
   			aspeed_video_start_frame(video);
   	}
@@ -931,10 +996,14 @@ static void aspeed_video_set_resolution(struct aspeed_video *video)
   				   FIELD_PREP(VE_TGS_FIRST, video->frame_top) |
   				   FIELD_PREP(VE_TGS_LAST,
   					      video->frame_bottom + 1));
-		aspeed_video_update(video, VE_CTRL, 0, VE_CTRL_INT_DE);
+		aspeed_video_update(video, VE_CTRL,
+				    VE_CTRL_INT_DE | VE_CTRL_DIRECT_FETCH,
+				    VE_CTRL_INT_DE);
   	} else {
   		v4l2_dbg(1, debug, &video->v4l2_dev, "Capture: Direct Mode\n");
-		aspeed_video_update(video, VE_CTRL, 0, VE_CTRL_DIRECT_FETCH);
+		aspeed_video_update(video, VE_CTRL,
+				    VE_CTRL_INT_DE | VE_CTRL_DIRECT_FETCH,
+				    VE_CTRL_DIRECT_FETCH);
   	}
size *= 4;
@@ -969,35 +1038,70 @@ static void aspeed_video_set_resolution(struct aspeed_video *video)
static void aspeed_video_update_regs(struct aspeed_video *video)
   {
-	u32 comp_ctrl = VE_COMP_CTRL_RSVD |
-		FIELD_PREP(VE_COMP_CTRL_DCT_LUM, video->jpeg_quality) |
-		FIELD_PREP(VE_COMP_CTRL_DCT_CHR, video->jpeg_quality | 0x10);
+	static const char * const compress_mode_str[] = {"DCT Only",
+		"DCT VQ mix 2-color", "DCT VQ mix 4-color"};
+	u32 comp_ctrl =	FIELD_PREP(VE_COMP_CTRL_DCT_LUM, video->jpeg_quality) |
+		FIELD_PREP(VE_COMP_CTRL_DCT_CHR, video->jpeg_quality | 0x10) |
+		FIELD_PREP(VE_COMP_CTRL_EN_HQ, video->hq_mode) |
+		FIELD_PREP(VE_COMP_CTRL_HQ_DCT_LUM, video->jpeg_hq_quality) |
+		FIELD_PREP(VE_COMP_CTRL_HQ_DCT_CHR, video->jpeg_hq_quality |
+			   0x10);
   	u32 ctrl = 0;
-	u32 seq_ctrl = VE_SEQ_CTRL_JPEG_MODE;
+	u32 seq_ctrl = 0;
- v4l2_dbg(1, debug, &video->v4l2_dev, "framerate(%d)\n",
-		 video->frame_rate);
-	v4l2_dbg(1, debug, &video->v4l2_dev, "subsample(%s)\n",
+	v4l2_dbg(1, debug, &video->v4l2_dev, "framerate(%d)\n", video->frame_rate);
+	v4l2_dbg(1, debug, &video->v4l2_dev, "jpeg format(%s) subsample(%s)\n",
+		 video->partial_jpeg ? "partial" : "standard",
   		 video->yuv420 ? "420" : "444");
-	v4l2_dbg(1, debug, &video->v4l2_dev, "compression quality(%d)\n",
-		 video->jpeg_quality);
+	v4l2_dbg(1, debug, &video->v4l2_dev, "compression quality(%d) hq(%s) hq_quality(%d)\n",
+		 video->jpeg_quality, video->hq_mode ? "on" : "off",
+		 video->jpeg_hq_quality);
+	v4l2_dbg(1, debug, &video->v4l2_dev, "compression mode(%s)\n",
+		 compress_mode_str[video->compression_mode]);
+
+	if (video->partial_jpeg)
+		aspeed_video_update(video, VE_BCD_CTRL, 0, VE_BCD_CTRL_EN_BCD);
+	else
+		aspeed_video_update(video, VE_BCD_CTRL, VE_BCD_CTRL_EN_BCD, 0);
if (video->frame_rate)
   		ctrl |= FIELD_PREP(VE_CTRL_FRC, video->frame_rate);
+ if (!video->partial_jpeg) {
+		comp_ctrl &= ~FIELD_PREP(VE_COMP_CTRL_EN_HQ, video->hq_mode);
+		seq_ctrl |= VE_SEQ_CTRL_JPEG_MODE;
+	}
+
   	if (video->yuv420)
   		seq_ctrl |= VE_SEQ_CTRL_YUV420;
if (video->jpeg.virt)
   		aspeed_video_update_jpeg_table(video->jpeg.virt, video->yuv420);
+#ifdef CONFIG_MACH_ASPEED_G4
+	switch (video->compression_mode) {
+	case 0:	//DCT only
+		comp_ctrl |= VE_COMP_CTRL_VQ_DCT_ONLY;
+		break;
+	case 1:	//DCT VQ mix 2-color
+		comp_ctrl &= ~(VE_COMP_CTRL_VQ_4COLOR | VE_COMP_CTRL_VQ_DCT_ONLY);
+		break;
+	case 2:	//DCT VQ mix 4-color
+		comp_ctrl |= VE_COMP_CTRL_VQ_4COLOR;
+		break;
+	}
+#endif
+
   	/* Set control registers */
   	aspeed_video_update(video, VE_SEQ_CTRL,
   			    VE_SEQ_CTRL_JPEG_MODE | VE_SEQ_CTRL_YUV420,
   			    seq_ctrl);
   	aspeed_video_update(video, VE_CTRL, VE_CTRL_FRC, ctrl);
   	aspeed_video_update(video, VE_COMP_CTRL,
-			    VE_COMP_CTRL_DCT_LUM | VE_COMP_CTRL_DCT_CHR,
+			    VE_COMP_CTRL_DCT_LUM | VE_COMP_CTRL_DCT_CHR |
+			    VE_COMP_CTRL_EN_HQ | VE_COMP_CTRL_HQ_DCT_LUM |
+			    VE_COMP_CTRL_HQ_DCT_CHR | VE_COMP_CTRL_VQ_4COLOR |
+			    VE_COMP_CTRL_VQ_DCT_ONLY,
   			    comp_ctrl);
   }
@@ -1029,6 +1133,8 @@ static void aspeed_video_init_regs(struct aspeed_video *video) /* Set mode detection defaults */
   	aspeed_video_write(video, VE_MODE_DETECT, 0x22666500);
+
+	aspeed_video_write(video, VE_BCD_CTRL, 0);
   }
static void aspeed_video_start(struct aspeed_video *video)
@@ -1062,6 +1168,9 @@ static void aspeed_video_stop(struct aspeed_video *video)
   	if (video->srcs[1].size)
   		aspeed_video_free_buf(video, &video->srcs[1]);
+ if (video->bcd.size)
+		aspeed_video_free_buf(video, &video->bcd);
+
   	video->v4l2_input_status = V4L2_IN_ST_NO_SIGNAL;
   	video->flags = 0;
   }
@@ -1364,6 +1473,28 @@ static int aspeed_video_set_ctrl(struct v4l2_ctrl *ctrl)
   		if (test_bit(VIDEO_STREAMING, &video->flags))
   			aspeed_video_update_regs(video);
   		break;
+	case V4L2_CID_ASPEED_FORMAT:
+		video->partial_jpeg = ctrl->val;
+		if (test_bit(VIDEO_STREAMING, &video->flags))
+			aspeed_video_update_regs(video);
+		break;
+#ifdef CONFIG_MACH_ASPEED_G4
+	case V4L2_CID_ASPEED_COMPRESSION_MODE:
+		video->compression_mode = ctrl->val;
+		if (test_bit(VIDEO_STREAMING, &video->flags))
+			aspeed_video_update_regs(video);
+		break;
+#endif
+	case V4L2_CID_ASPEED_HQ_MODE:
+		video->hq_mode = ctrl->val;
+		if (test_bit(VIDEO_STREAMING, &video->flags))
+			aspeed_video_update_regs(video);
+		break;
+	case V4L2_CID_ASPEED_HQ_JPEG_QUALITY:
+		video->jpeg_hq_quality = ctrl->val;
+		if (test_bit(VIDEO_STREAMING, &video->flags))
+			aspeed_video_update_regs(video);
+		break;
   	default:
   		return -EINVAL;
   	}
@@ -1375,6 +1506,52 @@ static const struct v4l2_ctrl_ops aspeed_video_ctrl_ops = {
   	.s_ctrl = aspeed_video_set_ctrl,
   };
+static const struct v4l2_ctrl_config aspeed_ctrl_format = {
+	.ops = &aspeed_video_ctrl_ops,
+	.id = V4L2_CID_ASPEED_FORMAT,
+	.name = "Aspeed JPEG Format",
+	.type = V4L2_CTRL_TYPE_BOOLEAN,
+	.min = false,
+	.max = true,
+	.step = 1,
+	.def = false,
+};
+
+#ifdef CONFIG_MACH_ASPEED_G4
+static const struct v4l2_ctrl_config aspeed_ctrl_compression_mode = {
+	.ops = &aspeed_video_ctrl_ops,
+	.id = V4L2_CID_ASPEED_COMPRESSION_MODE,
+	.name = "Aspeed Compression Mode",
+	.type = V4L2_CTRL_TYPE_INTEGER,
+	.min = 0,
+	.max = 2,
+	.step = 1,
+	.def = 0,
+};
+#endif
+
+static const struct v4l2_ctrl_config aspeed_ctrl_HQ_mode = {
+	.ops = &aspeed_video_ctrl_ops,
+	.id = V4L2_CID_ASPEED_HQ_MODE,
+	.name = "Aspeed HQ Mode",
+	.type = V4L2_CTRL_TYPE_BOOLEAN,
+	.min = false,
+	.max = true,
+	.step = 1,
+	.def = false,
+};
+
+static const struct v4l2_ctrl_config aspeed_ctrl_HQ_jpeg_quality = {
+	.ops = &aspeed_video_ctrl_ops,
+	.id = V4L2_CID_ASPEED_HQ_JPEG_QUALITY,
+	.name = "Aspeed HQ Quality",
+	.type = V4L2_CTRL_TYPE_INTEGER,
+	.min = 0,
+	.max = ASPEED_VIDEO_JPEG_NUM_QUALITIES - 1,
+	.step = 1,
+	.def = 0,
+};
+
   static void aspeed_video_resolution_work(struct work_struct *work)
   {
   	struct delayed_work *dwork = to_delayed_work(work);
@@ -1644,6 +1821,7 @@ static int aspeed_video_setup_video(struct aspeed_video *video)
   	struct v4l2_device *v4l2_dev = &video->v4l2_dev;
   	struct vb2_queue *vbq = &video->queue;
   	struct video_device *vdev = &video->vdev;
+	struct v4l2_ctrl_handler *hdl = &video->ctrl_handler;
   	int rc;
video->pix_fmt.pixelformat = V4L2_PIX_FMT_JPEG;
@@ -1658,22 +1836,28 @@ static int aspeed_video_setup_video(struct aspeed_video *video)
   		return rc;
   	}
- v4l2_ctrl_handler_init(&video->ctrl_handler, 2);
-	v4l2_ctrl_new_std(&video->ctrl_handler, &aspeed_video_ctrl_ops,
+	v4l2_ctrl_handler_init(hdl, 6);
+	v4l2_ctrl_new_std(hdl, &aspeed_video_ctrl_ops,
   			  V4L2_CID_JPEG_COMPRESSION_QUALITY, 0,
   			  ASPEED_VIDEO_JPEG_NUM_QUALITIES - 1, 1, 0);
-	v4l2_ctrl_new_std_menu(&video->ctrl_handler, &aspeed_video_ctrl_ops,
+	v4l2_ctrl_new_std_menu(hdl, &aspeed_video_ctrl_ops,
   			       V4L2_CID_JPEG_CHROMA_SUBSAMPLING,
   			       V4L2_JPEG_CHROMA_SUBSAMPLING_420, mask,
   			       V4L2_JPEG_CHROMA_SUBSAMPLING_444);
+	v4l2_ctrl_new_custom(hdl, &aspeed_ctrl_format, NULL);
+#ifdef CONFIG_MACH_ASPEED_G4
+	v4l2_ctrl_new_custom(hdl, &aspeed_ctrl_compression_mode, NULL);
+#endif
+	v4l2_ctrl_new_custom(hdl, &aspeed_ctrl_HQ_mode, NULL);
+	v4l2_ctrl_new_custom(hdl, &aspeed_ctrl_HQ_jpeg_quality, NULL);
- rc = video->ctrl_handler.error;
+	rc = hdl->error;
   	if (rc) {
   		dev_err(video->dev, "Failed to init controls: %d\n", rc);
   		goto err_ctrl_init;
   	}
- v4l2_dev->ctrl_handler = &video->ctrl_handler;
+	v4l2_dev->ctrl_handler = hdl;
vbq->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
   	vbq->io_modes = VB2_MMAP | VB2_READ | VB2_DMABUF;

--
Best Regards
Jammy




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