[PATCH v10 12/17] media: platform: Add mali-c55 3a stats devnode

Daniel Scally
2025-06-24T10:21:56Z

Add a new code file to govern the 3a statistics capture node.

On ISP_START, fill the stats buffer by reading out the metering space
in the ISP's memory. This is done for the non-active config just as
the dma transfer of the registers is. To acheive that, move the
checking of the current config outside of mali_c55_swap_next_config()
so we can use it for both functions.

Acked-by: Nayden Kanchev <nayden.kanchev@arm.com>
Co-developed-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Signed-off-by: Daniel Scally <dan.scally@ideasonboard.com>
---
Changes in v10:

- Account for v2 of media jobs framework

Changes in v9:

- Squashed the originally separate patch that filled the stats buffer on
the ISP start interrupt into this patch.
- A couple of differences accounting for the different way of operating
in inline and memory input mode
- Infrastructure for the media jobs framework.
- Include this video device in the synchronised start/stop across the
pipeline

Changes in v8:

- None

Changes in v7:

- Set width and height of MEDIA_BUS_FMT_METADATA_FIXED to 0.
- Added cpu fallback to stats in the event of no DMA channel acquired
- Terminate ISP streaming in the statistics vb2 stop streaming function

Changes in v6:

- Fixed mising includes
- Minor renames and formatting
- Reworked mali_c55_stats_metering_complete() so it could only return
buffers when both halves of the DMA read were done
- Terminate dma transfers on streamoff

Changes in v5:

- New patch
---
drivers/media/platform/arm/mali-c55/Makefile | 1 +
.../media/platform/arm/mali-c55/mali-c55-common.h | 30 ++
.../media/platform/arm/mali-c55/mali-c55-core.c | 45 +-
drivers/media/platform/arm/mali-c55/mali-c55-isp.c | 11 +
.../platform/arm/mali-c55/mali-c55-registers.h | 3 +
.../media/platform/arm/mali-c55/mali-c55-stats.c | 528 +++++++++++++++++++++
6 files changed, 609 insertions(+), 9 deletions(-)

diff --git a/drivers/media/platform/arm/mali-c55/Makefile b/drivers/media/platform/arm/mali-c55/Makefile
index 9178ac35e50efdc42289f5ed5e3ef5af55e8ac32..b5a22d414479dd1eb6435f474cb95aaa14879aa8 100644
--- a/drivers/media/platform/arm/mali-c55/Makefile
+++ b/drivers/media/platform/arm/mali-c55/Makefile
@@ -4,6 +4,7 @@ mali-c55-y := mali-c55-capture.o \
mali-c55-core.o \
mali-c55-isp.o \
mali-c55-resizer.o \
+ mali-c55-stats.o \
mali-c55-tpg.o

obj-$(CONFIG_VIDEO_MALI_C55) += mali-c55.o
diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-common.h b/drivers/media/platform/arm/mali-c55/mali-c55-common.h
index 979fb448e56801d47775ac282a651a6c913e58a8..51291ba8d0031918ba472c34b0720f1d5129089e 100644
--- a/drivers/media/platform/arm/mali-c55/mali-c55-common.h
+++ b/drivers/media/platform/arm/mali-c55/mali-c55-common.h
@@ -54,6 +54,7 @@ enum mali_c55_isp_pads {
MALI_C55_ISP_PAD_SINK_VIDEO,
MALI_C55_ISP_PAD_SOURCE_VIDEO,
MALI_C55_ISP_PAD_SOURCE_BYPASS,
+ MALI_C55_ISP_PAD_SOURCE_STATS,
MALI_C55_ISP_NUM_PADS,
};

@@ -164,6 +165,30 @@ struct mali_c55_cap_dev {
} buffers;
};

+struct mali_c55_stats_buf {
+ struct vb2_v4l2_buffer vb;
+ unsigned int segments_remaining;
+ struct list_head queue;
+ bool failed;
+};
+
+struct mali_c55_stats {
+ struct mali_c55 *mali_c55;
+ struct video_device vdev;
+ struct dma_chan *channel;
+ struct vb2_queue queue;
+ struct media_pad pad;
+ /* Mutex to provide to vb2 */
+ struct mutex lock;
+
+ struct {
+ /* Spinlock to guard buffer queue */
+ spinlock_t lock;
+ struct list_head queue;
+ struct list_head pending;
+ } buffers;
+};
+
enum mali_c55_config_spaces {
MALI_C55_CONFIG_PING,
MALI_C55_CONFIG_PONG,
@@ -209,6 +234,7 @@ struct mali_c55 {
struct mali_c55_isp isp;
struct mali_c55_resizer resizers[MALI_C55_NUM_RSZS];
struct mali_c55_cap_dev cap_devs[MALI_C55_NUM_CAP_DEVS];
+ struct mali_c55_stats stats;

struct mali_c55_context context;
u32 next_config;
@@ -237,6 +263,8 @@ int mali_c55_register_resizers(struct mali_c55 *mali_c55);
void mali_c55_unregister_resizers(struct mali_c55 *mali_c55);
int mali_c55_register_capture_devs(struct mali_c55 *mali_c55);
void mali_c55_unregister_capture_devs(struct mali_c55 *mali_c55);
+int mali_c55_register_stats(struct mali_c55 *mali_c55);
+void mali_c55_unregister_stats(struct mali_c55 *mali_c55);
struct mali_c55_context *mali_c55_get_active_context(struct mali_c55 *mali_c55);
void mali_c55_set_plane_done(struct mali_c55_cap_dev *cap_dev,
enum mali_c55_planes plane);
@@ -254,5 +282,7 @@ mali_c55_isp_get_mbus_config_by_shifted_code(u32 code);
const struct mali_c55_isp_format_info *
mali_c55_isp_get_mbus_config_by_index(u32 index);
bool mali_c55_pipeline_ready(struct media_pipeline *pipe);
+void mali_c55_stats_fill_buffer(struct mali_c55 *mali_c55,
+ enum mali_c55_config_spaces cfg_space);

#endif /* _MALI_C55_COMMON_H */
diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-core.c b/drivers/media/platform/arm/mali-c55/mali-c55-core.c
index 1e0554d659abfd96ec6e9c05cc530d7289c992b7..e3550cb936a78c3d34d59a9b1882c062d4f2c2f6 100644
--- a/drivers/media/platform/arm/mali-c55/mali-c55-core.c
+++ b/drivers/media/platform/arm/mali-c55/mali-c55-core.c
@@ -378,6 +378,16 @@ static int mali_c55_create_links(struct mali_c55 *mali_c55)
}
}

+ ret = media_create_pad_link(&mali_c55->isp.sd.entity,
+ MALI_C55_ISP_PAD_SOURCE_STATS,
+ &mali_c55->stats.vdev.entity, 0,
+ MEDIA_LNK_FL_ENABLED);
+ if (ret) {
+ dev_err(mali_c55->dev,
+ "failed to link ISP and 3a stats node\n");
+ goto err_remove_links;
+ }
+
return 0;

err_remove_links:
@@ -392,19 +402,13 @@ static void mali_c55_unregister_entities(struct mali_c55 *mali_c55)
mali_c55_unregister_isp(mali_c55);
mali_c55_unregister_resizers(mali_c55);
mali_c55_unregister_capture_devs(mali_c55);
+ mali_c55_unregister_stats(mali_c55);
}

static void mali_c55_swap_next_config(struct mali_c55 *mali_c55)
{
struct mali_c55_context *ctx = mali_c55_get_active_context(mali_c55);

- u32 curr_config;
-
- curr_config = mali_c55_read(mali_c55, MALI_C55_REG_PING_PONG_READ);
- curr_config = (curr_config & MALI_C55_REG_PING_PONG_READ_MASK)
- >> (ffs(MALI_C55_REG_PING_PONG_READ_MASK) - 1);
- mali_c55->next_config = curr_config ^ 1;
-
mali_c55_config_write(ctx, mali_c55->next_config ?
MALI_C55_CONFIG_PING : MALI_C55_CONFIG_PONG,
false);
@@ -436,7 +440,7 @@ static int mali_c55_populate_media_job(struct media_job *job, void *data)
* the others with the same flag.
*/
return media_jobs_add_job_step(job, mali_c55_core_run_step, mali_c55,
- MEDIA_JOBS_FL_STEP_ANYWHERE, 0);
+ MEDIA_JOBS_FL_STEP_ANYWHERE, 1);
}

static struct media_job_contributor_ops mali_c55_core_media_job_ops = {
@@ -481,6 +485,10 @@ static int mali_c55_register_entities(struct mali_c55 *mali_c55)
if (ret)
goto err_unregister_entities;

+ ret = mali_c55_register_stats(mali_c55);
+ if (ret)
+ goto err_unregister_entities;
+
ret = mali_c55_create_links(mali_c55);
if (ret)
goto err_unregister_entities;
@@ -699,6 +707,7 @@ static irqreturn_t mali_c55_isr(int irq, void *context)
struct device *dev = context;
struct mali_c55 *mali_c55 = dev_get_drvdata(dev);
u32 interrupt_status;
+ u32 curr_config;
unsigned int i;

interrupt_status = mali_c55_read(mali_c55,
@@ -721,8 +730,26 @@ static irqreturn_t mali_c55_isr(int irq, void *context)

__mali_c55_set_next_buffer(mali_c55);

- if (mali_c55->inline_mode)
+ /*
+ * When the ISP starts a frame we have some work to do:
+ *
+ * 1. Copy over the config for the **next** frame
+ * 2. Read out the metering stats for the **last** frame
+ */
+
+ curr_config = mali_c55_read(mali_c55,
+ MALI_C55_REG_PING_PONG_READ);
+ curr_config &= MALI_C55_REG_PING_PONG_READ_MASK;
+ curr_config >>= ffs(MALI_C55_REG_PING_PONG_READ_MASK) - 1;
+ mali_c55->next_config = curr_config ^ 1;
+
+ if (mali_c55->inline_mode) {
+ mali_c55_stats_fill_buffer(mali_c55,
+ mali_c55->next_config ?
+ MALI_C55_CONFIG_PING :
+ MALI_C55_CONFIG_PONG);
mali_c55_swap_next_config(mali_c55);
+ }

break;
case MALI_C55_IRQ_ISP_DONE:
diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-isp.c b/drivers/media/platform/arm/mali-c55/mali-c55-isp.c
index 20d4d16c75fbf0d5519ecadb5ed1d080bdae05de..b9b2806a5eb302c62ca7c20539551e422293ff36 100644
--- a/drivers/media/platform/arm/mali-c55/mali-c55-isp.c
+++ b/drivers/media/platform/arm/mali-c55/mali-c55-isp.c
@@ -5,6 +5,8 @@
* Copyright (C) 2024 Ideas on Board Oy
*/

+#include <linux/media/arm/mali-c55-config.h>
+
#include <linux/delay.h>
#include <linux/iopoll.h>
#include <linux/property.h>
@@ -512,6 +514,14 @@ static int mali_c55_isp_init_state(struct v4l2_subdev *sd,
in_crop->width = MALI_C55_DEFAULT_WIDTH;
in_crop->height = MALI_C55_DEFAULT_HEIGHT;

+ src_fmt = v4l2_subdev_state_get_format(state,
+ MALI_C55_ISP_PAD_SOURCE_STATS);
+
+ src_fmt->width = 0;
+ src_fmt->height = 0;
+ src_fmt->field = V4L2_FIELD_NONE;
+ src_fmt->code = MEDIA_BUS_FMT_METADATA_FIXED;
+
return 0;
}

@@ -609,6 +619,7 @@ int mali_c55_register_isp(struct mali_c55 *mali_c55)
MEDIA_PAD_FL_MUST_CONNECT;
isp->pads[MALI_C55_ISP_PAD_SOURCE_VIDEO].flags = MEDIA_PAD_FL_SOURCE;
isp->pads[MALI_C55_ISP_PAD_SOURCE_BYPASS].flags = MEDIA_PAD_FL_SOURCE;
+ isp->pads[MALI_C55_ISP_PAD_SOURCE_STATS].flags = MEDIA_PAD_FL_SOURCE;

ret = media_entity_pads_init(&sd->entity, MALI_C55_ISP_NUM_PADS,
isp->pads);
diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-registers.h b/drivers/media/platform/arm/mali-c55/mali-c55-registers.h
index 36a81be0191a15da91809dd2da5d279716f6d725..58dd6ce556a096ede4d3a21e472fdb9ed1cf5de3 100644
--- a/drivers/media/platform/arm/mali-c55/mali-c55-registers.h
+++ b/drivers/media/platform/arm/mali-c55/mali-c55-registers.h
@@ -103,6 +103,9 @@ enum mali_c55_interrupts {
#define MALI_C55_VC_START(v) ((v) & 0xffff)
#define MALI_C55_VC_SIZE(v) (((v) & 0xffff) << 16)

+#define MALI_C55_REG_1024BIN_HIST 0x054a8
+#define MALI_C55_1024BIN_HIST_SIZE 4096
+
/* Ping/Pong Configuration Space */
#define MALI_C55_REG_BASE_ADDR 0x18e88
#define MALI_C55_REG_BYPASS_0 0x18eac
diff --git a/drivers/media/platform/arm/mali-c55/mali-c55-stats.c b/drivers/media/platform/arm/mali-c55/mali-c55-stats.c
new file mode 100644
index 0000000000000000000000000000000000000000..4bda386f3afa2e3b05a66f019f6d57b9cf2904fb
--- /dev/null
+++ b/drivers/media/platform/arm/mali-c55/mali-c55-stats.c
@@ -0,0 +1,528 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ARM Mali-C55 ISP Driver - 3A Statistics capture device
+ *
+ * Copyright (C) 2023 Ideas on Board Oy
+ */
+
+#include <linux/container_of.h>
+#include <linux/dev_printk.h>
+#include <linux/dmaengine.h>
+#include <linux/list.h>
+#include <linux/media/arm/mali-c55-config.h>
+#include <linux/mutex.h>
+#include <linux/pm_runtime.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+
+#include <media/media-entity.h>
+#include <media/v4l2-dev.h>
+#include <media/v4l2-event.h>
+#include <media/v4l2-fh.h>
+#include <media/v4l2-ioctl.h>
+#include <media/videobuf2-core.h>
+#include <media/videobuf2-dma-contig.h>
+
+#include "mali-c55-common.h"
+#include "mali-c55-registers.h"
+
+static const unsigned int metering_space_addrs[] = {
+ [MALI_C55_CONFIG_PING] = 0x095ac,
+ [MALI_C55_CONFIG_PONG] = 0x2156c,
+};
+
+static int mali_c55_stats_enum_fmt_meta_cap(struct file *file, void *fh,
+ struct v4l2_fmtdesc *f)
+{
+ if (f->index)
+ return -EINVAL;
+
+ f->pixelformat = V4L2_META_FMT_MALI_C55_STATS;
+
+ return 0;
+}
+
+static int mali_c55_stats_g_fmt_meta_cap(struct file *file, void *fh,
+ struct v4l2_format *f)
+{
+ static const struct v4l2_meta_format mfmt = {
+ .dataformat = V4L2_META_FMT_MALI_C55_STATS,
+ .buffersize = sizeof(struct mali_c55_stats_buffer)
+ };
+
+ f->fmt.meta = mfmt;
+
+ return 0;
+}
+
+static int mali_c55_stats_querycap(struct file *file,
+ void *priv, struct v4l2_capability *cap)
+{
+ strscpy(cap->driver, MALI_C55_DRIVER_NAME, sizeof(cap->driver));
+ strscpy(cap->card, "ARM Mali-C55 ISP", sizeof(cap->card));
+
+ return 0;
+}
+
+static const struct v4l2_ioctl_ops mali_c55_stats_v4l2_ioctl_ops = {
+ .vidioc_reqbufs = vb2_ioctl_reqbufs,
+ .vidioc_querybuf = vb2_ioctl_querybuf,
+ .vidioc_create_bufs = vb2_ioctl_create_bufs,
+ .vidioc_qbuf = vb2_ioctl_qbuf,
+ .vidioc_expbuf = vb2_ioctl_expbuf,
+ .vidioc_dqbuf = vb2_ioctl_dqbuf,
+ .vidioc_prepare_buf = vb2_ioctl_prepare_buf,
+ .vidioc_streamon = vb2_ioctl_streamon,
+ .vidioc_streamoff = vb2_ioctl_streamoff,
+ .vidioc_enum_fmt_meta_cap = mali_c55_stats_enum_fmt_meta_cap,
+ .vidioc_g_fmt_meta_cap = mali_c55_stats_g_fmt_meta_cap,
+ .vidioc_s_fmt_meta_cap = mali_c55_stats_g_fmt_meta_cap,
+ .vidioc_try_fmt_meta_cap = mali_c55_stats_g_fmt_meta_cap,
+ .vidioc_querycap = mali_c55_stats_querycap,
+ .vidioc_subscribe_event = v4l2_ctrl_subscribe_event,
+ .vidioc_unsubscribe_event = v4l2_event_unsubscribe,
+};
+
+static const struct v4l2_file_operations mali_c55_stats_v4l2_fops = {
+ .owner = THIS_MODULE,
+ .unlocked_ioctl = video_ioctl2,
+ .open = v4l2_fh_open,
+ .release = vb2_fop_release,
+ .poll = vb2_fop_poll,
+ .mmap = vb2_fop_mmap,
+};
+
+static int
+mali_c55_stats_queue_setup(struct vb2_queue *q, unsigned int *num_buffers,
+ unsigned int *num_planes, unsigned int sizes[],
+ struct device *alloc_devs[])
+{
+ struct mali_c55_stats *stats = vb2_get_drv_priv(q);
+
+ if (*num_planes && *num_planes > 1)
+ return -EINVAL;
+
+ if (sizes[0] && sizes[0] < sizeof(struct mali_c55_stats_buffer))
+ return -EINVAL;
+
+ *num_planes = 1;
+
+ if (!sizes[0])
+ sizes[0] = sizeof(struct mali_c55_stats_buffer);
+
+ if (stats->channel)
+ alloc_devs[0] = stats->channel->device->dev;
+
+ return 0;
+}
+
+static void mali_c55_stats_buf_queue(struct vb2_buffer *vb)
+{
+ struct mali_c55_stats *stats = vb2_get_drv_priv(vb->vb2_queue);
+ struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+ struct mali_c55_stats_buf *buf = container_of(vbuf,
+ struct mali_c55_stats_buf, vb);
+ struct mali_c55 *mali_c55 = stats->mali_c55;
+ struct list_head *queue;
+
+ vb2_set_plane_payload(vb, 0, sizeof(struct mali_c55_stats_buffer));
+ buf->segments_remaining = 2;
+ buf->failed = false;
+
+ queue = mali_c55->inline_mode ? &stats->buffers.queue :
+ &stats->buffers.pending;
+
+ spin_lock(&stats->buffers.lock);
+ list_add_tail(&buf->queue, queue);
+ spin_unlock(&stats->buffers.lock);
+
+ media_jobs_try_queue_job(stats->mali_c55->sched,
+ MEDIA_JOB_TYPE_PIPELINE_PULSE);
+}
+
+static void mali_c55_stats_return_buffers(struct mali_c55_stats *stats,
+ enum vb2_buffer_state state)
+{
+ struct mali_c55_stats_buf *buf, *tmp;
+
+ guard(spinlock)(&stats->buffers.lock);
+
+ list_for_each_entry_safe(buf, tmp, &stats->buffers.queue, queue) {
+ list_del(&buf->queue);
+ vb2_buffer_done(&buf->vb.vb2_buf, state);
+ }
+
+ list_for_each_entry_safe(buf, tmp, &stats->buffers.pending, queue) {
+ list_del(&buf->queue);
+ vb2_buffer_done(&buf->vb.vb2_buf, state);
+ }
+}
+
+static int mali_c55_stats_start_streaming(struct vb2_queue *q,
+ unsigned int count)
+{
+ struct mali_c55_stats *stats = vb2_get_drv_priv(q);
+ struct mali_c55 *mali_c55 = stats->mali_c55;
+ struct media_pipeline *pipe;
+ int ret;
+
+ ret = pm_runtime_resume_and_get(mali_c55->dev);
+ if (ret)
+ goto err_return_buffers;
+
+ ret = video_device_pipeline_alloc_start(&stats->vdev);
+ if (ret)
+ goto err_pm_put;
+
+ pipe = video_device_pipeline(&stats->vdev);
+ if (mali_c55_pipeline_ready(pipe)) {
+ ret = media_pipeline_started(pipe);
+ if (ret)
+ goto err_stop_pipeline;
+
+ media_jobs_run_jobs(stats->mali_c55->sched);
+ }
+
+ return 0;
+
+err_stop_pipeline:
+ video_device_pipeline_stop(&stats->vdev);
+err_pm_put:
+ pm_runtime_put(mali_c55->dev);
+err_return_buffers:
+ mali_c55_stats_return_buffers(stats, VB2_BUF_STATE_QUEUED);
+
+ return ret;
+}
+
+static void mali_c55_stats_stop_streaming(struct vb2_queue *q)
+{
+ struct mali_c55_stats *stats = vb2_get_drv_priv(q);
+ struct media_pipeline *pipe;
+
+ if (stats->channel)
+ dmaengine_terminate_sync(stats->channel);
+
+ pipe = video_device_pipeline(&stats->vdev);
+ if (mali_c55_pipeline_ready(pipe)) {
+ media_pipeline_stopped(pipe);
+ media_jobs_cancel_jobs(stats->mali_c55->sched);
+ }
+
+ video_device_pipeline_stop(&stats->vdev);
+ mali_c55_stats_return_buffers(stats, VB2_BUF_STATE_ERROR);
+}
+
+static const struct vb2_ops mali_c55_stats_vb2_ops = {
+ .queue_setup = mali_c55_stats_queue_setup,
+ .buf_queue = mali_c55_stats_buf_queue,
+ .wait_prepare = vb2_ops_wait_prepare,
+ .wait_finish = vb2_ops_wait_finish,
+ .start_streaming = mali_c55_stats_start_streaming,
+ .stop_streaming = mali_c55_stats_stop_streaming,
+};
+
+static bool mali_c55_stats_job_ready(void *data)
+{
+ struct mali_c55_stats *stats = data;
+ if (IS_ERR_OR_NULL(media_pad_remote_pad_unique(&stats->pad)))
+ return true;
+
+ guard(spinlock)(&stats->buffers.lock);
+
+ if (list_empty(&stats->buffers.pending))
+ return false;
+
+ return true;
+}
+
+static void mali_c55_stats_job_queue(void *data)
+{
+ struct mali_c55_stats *stats = data;
+ struct mali_c55_stats_buf *buf;
+
+ if (IS_ERR_OR_NULL(media_pad_remote_pad_unique(&stats->pad)))
+ return;
+
+ guard(spinlock)(&stats->buffers.lock);
+ buf = list_first_entry(&stats->buffers.pending,
+ struct mali_c55_stats_buf, queue);
+ list_move_tail(&buf->queue, &stats->buffers.queue);
+}
+
+static void mali_c55_stats_job_abort(void *data)
+{
+ struct mali_c55_stats *stats = data;
+ struct mali_c55_stats_buf *buf;
+
+ guard(spinlock)(&stats->buffers.lock);
+ buf = list_first_entry(&stats->buffers.queue,
+ struct mali_c55_stats_buf, queue);
+
+ if (buf)
+ list_move(&buf->queue, &stats->buffers.pending);
+}
+
+static void mali_c55_stats_run_step(void *data)
+{
+ struct mali_c55_stats *stats = data;
+ struct mali_c55 *mali_c55 = stats->mali_c55;
+ enum mali_c55_config_spaces cfg_space;
+
+ cfg_space = mali_c55->next_config ? MALI_C55_CONFIG_PING :
+ MALI_C55_CONFIG_PONG;
+
+ mali_c55_stats_fill_buffer(mali_c55, cfg_space);
+}
+
+static int mali_c55_stats_job_add_steps(struct media_job *job, void *data)
+{
+ return media_jobs_add_job_step(job, mali_c55_stats_run_step, data,
+ MEDIA_JOBS_FL_STEP_FROM_BACK, 0);
+}
+
+static struct media_job_contributor_ops mali_c55_stats_media_job_ops = {
+ .add_steps = mali_c55_stats_job_add_steps,
+ .ready = mali_c55_stats_job_ready,
+ .queue = mali_c55_stats_job_queue,
+ .abort = mali_c55_stats_job_abort
+};
+
+static void
+mali_c55_stats_metering_complete(void *param,
+ const struct dmaengine_result *result)
+{
+ struct mali_c55_stats_buf *buf = param;
+
+ if (result->result != DMA_TRANS_NOERROR)
+ buf->failed = true;
+
+ if (!--buf->segments_remaining)
+ vb2_buffer_done(&buf->vb.vb2_buf, buf->failed ?
+ VB2_BUF_STATE_ERROR : VB2_BUF_STATE_DONE);
+}
+
+static int mali_c55_stats_dma_xfer(struct mali_c55_stats *stats, dma_addr_t src,
+ dma_addr_t dst,
+ struct mali_c55_stats_buf *buf,
+ size_t length)
+{
+ struct dma_async_tx_descriptor *tx;
+ dma_cookie_t cookie;
+
+ tx = dmaengine_prep_dma_memcpy(stats->channel, dst, src, length, 0);
+ if (!tx) {
+ dev_err(stats->mali_c55->dev, "failed to prep stats DMA\n");
+ return -EIO;
+ }
+
+ tx->callback_result = mali_c55_stats_metering_complete;
+ tx->callback_param = buf;
+
+ cookie = dmaengine_submit(tx);
+ if (dma_submit_error(cookie)) {
+ dev_err(stats->mali_c55->dev, "failed to submit stats DMA\n");
+ return -EIO;
+ }
+
+ dma_async_issue_pending(stats->channel);
+ return 0;
+}
+
+static int mali_c55_stats_dma_read(struct mali_c55_stats *stats,
+ struct mali_c55_stats_buf *buf,
+ enum mali_c55_config_spaces cfg_space)
+{
+ struct mali_c55 *mali_c55 = stats->mali_c55;
+ struct mali_c55_context *ctx = mali_c55_get_active_context(mali_c55);
+ dma_addr_t src, dst;
+ size_t length;
+ int ret;
+
+ /*
+ * There are in fact two noncontiguous sections of the ISP's
+ * memory space that hold statistics for 3a algorithms to use: A
+ * section in each config space and a global section holding
+ * histograms which is double buffered and so holds data for the
+ * last frame. We need to read both.
+ */
+ src = ctx->base + MALI_C55_REG_1024BIN_HIST;
+ dst = vb2_dma_contig_plane_dma_addr(&buf->vb.vb2_buf, 0);
+
+ ret = mali_c55_stats_dma_xfer(stats, src, dst, buf,
+ MALI_C55_1024BIN_HIST_SIZE);
+ if (ret)
+ return ret;
+
+ src = ctx->base + metering_space_addrs[cfg_space];
+ dst += MALI_C55_1024BIN_HIST_SIZE;
+
+ length = sizeof(struct mali_c55_stats_buffer) - MALI_C55_1024BIN_HIST_SIZE;
+ ret = mali_c55_stats_dma_xfer(stats, src, dst, buf, length);
+ if (ret) {
+ dmaengine_terminate_sync(stats->channel);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void mali_c55_stats_cpu_read(struct mali_c55_stats *stats,
+ struct mali_c55_stats_buf *buf,
+ enum mali_c55_config_spaces cfg_space)
+{
+ struct mali_c55 *mali_c55 = stats->mali_c55;
+ size_t length;
+ void *src;
+ void *dst;
+
+ src = mali_c55->base + MALI_C55_REG_1024BIN_HIST;
+ dst = vb2_plane_vaddr(&buf->vb.vb2_buf, 0);
+ memcpy_fromio(dst, src, MALI_C55_1024BIN_HIST_SIZE);
+
+ src = mali_c55->base + metering_space_addrs[cfg_space];
+ dst += MALI_C55_1024BIN_HIST_SIZE;
+ length = sizeof(struct mali_c55_stats_buffer) - MALI_C55_1024BIN_HIST_SIZE;
+ memcpy_fromio(dst, src, length);
+}
+
+void mali_c55_stats_fill_buffer(struct mali_c55 *mali_c55,
+ enum mali_c55_config_spaces cfg_space)
+{
+ struct mali_c55_stats *stats = &mali_c55->stats;
+ struct mali_c55_stats_buf *buf = NULL;
+ int ret;
+
+ spin_lock(&stats->buffers.lock);
+ if (!list_empty(&stats->buffers.queue)) {
+ buf = list_first_entry(&stats->buffers.queue,
+ struct mali_c55_stats_buf, queue);
+ list_del(&buf->queue);
+ }
+ spin_unlock(&stats->buffers.lock);
+
+ if (!buf)
+ return;
+
+ buf->vb.sequence = mali_c55->isp.frame_sequence;
+ buf->vb.vb2_buf.timestamp = ktime_get_boottime_ns();
+
+ if (stats->channel) {
+ ret = mali_c55_stats_dma_read(stats, buf, cfg_space);
+ if (ret)
+ vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
+ } else {
+ mali_c55_stats_cpu_read(stats, buf, cfg_space);
+ vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_DONE);
+ }
+}
+
+void mali_c55_unregister_stats(struct mali_c55 *mali_c55)
+{
+ struct mali_c55_stats *stats = &mali_c55->stats;
+
+ if (!video_is_registered(&stats->vdev))
+ return;
+
+ vb2_video_unregister_device(&stats->vdev);
+ media_entity_cleanup(&stats->vdev.entity);
+
+ if (stats->channel)
+ dma_release_channel(stats->channel);
+
+ mutex_destroy(&stats->lock);
+}
+
+int mali_c55_register_stats(struct mali_c55 *mali_c55)
+{
+ struct mali_c55_stats *stats = &mali_c55->stats;
+ struct video_device *vdev = &stats->vdev;
+ struct vb2_queue *vb2q = &stats->queue;
+ dma_cap_mask_t mask;
+ int ret;
+
+ mutex_init(&stats->lock);
+ INIT_LIST_HEAD(&stats->buffers.queue);
+ INIT_LIST_HEAD(&stats->buffers.pending);
+ spin_lock_init(&stats->buffers.lock);
+
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_MEMCPY, mask);
+
+ /*
+ * No failure here, because we will just fallback on memcpy if there is
+ * no usable DMA channel on the system.
+ */
+ stats->channel = dma_request_channel(mask, 0, NULL);
+ if (!stats->channel)
+ dev_dbg(mali_c55->dev,
+ "No DMA channel for stats, falling back to memcpy\n");
+
+ stats->pad.flags = MEDIA_PAD_FL_SINK;
+ ret = media_entity_pads_init(&stats->vdev.entity, 1, &stats->pad);
+ if (ret)
+ goto err_release_dma_channel;
+
+ vb2q->type = V4L2_BUF_TYPE_META_CAPTURE;
+ vb2q->io_modes = VB2_MMAP | VB2_DMABUF;
+ vb2q->drv_priv = stats;
+ vb2q->mem_ops = &vb2_dma_contig_memops;
+ vb2q->ops = &mali_c55_stats_vb2_ops;
+ vb2q->buf_struct_size = sizeof(struct mali_c55_stats_buf);
+ vb2q->min_queued_buffers = 1;
+ vb2q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
+ vb2q->lock = &stats->lock;
+ vb2q->dev = stats->channel ? stats->channel->device->dev : mali_c55->dev;
+
+ ret = vb2_queue_init(vb2q);
+ if (ret) {
+ dev_err(mali_c55->dev, "stats vb2 queue init failed\n");
+ goto err_cleanup_entity;
+ }
+
+ strscpy(stats->vdev.name, "mali-c55 3a stats", sizeof(stats->vdev.name));
+ vdev->release = video_device_release_empty;
+ vdev->fops = &mali_c55_stats_v4l2_fops;
+ vdev->ioctl_ops = &mali_c55_stats_v4l2_ioctl_ops;
+ vdev->lock = &stats->lock;
+ vdev->v4l2_dev = &mali_c55->v4l2_dev;
+ vdev->queue = &stats->queue;
+ vdev->device_caps = V4L2_CAP_META_CAPTURE | V4L2_CAP_STREAMING;
+ vdev->vfl_dir = VFL_DIR_RX;
+ video_set_drvdata(vdev, stats);
+
+ ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1);
+ if (ret) {
+ dev_err(mali_c55->dev,
+ "failed to register stats video device\n");
+ goto err_release_vb2q;
+ }
+
+
+ ret = media_jobs_register_job_contributor(mali_c55->sched,
+ &mali_c55_stats_media_job_ops,
+ stats,
+ MEDIA_JOB_TYPE_PIPELINE_PULSE);
+ if (ret) {
+ dev_err(mali_c55->dev, "Failed to add media job setup func\n");
+ goto err_unregister_video_device;
+ }
+
+ stats->mali_c55 = mali_c55;
+
+ return 0;
+
+err_unregister_video_device:
+ video_unregister_device(vdev);
+err_release_vb2q:
+ vb2_queue_release(vb2q);
+err_cleanup_entity:
+ media_entity_cleanup(&stats->vdev.entity);
+err_release_dma_channel:
+ if (stats->channel)
+ dma_release_channel(stats->channel);
+
+ mutex_destroy(&stats->lock);
+
+ return ret;
+}

--
2.34.1