Re: [RFC,v3 7/9] media: platform: Add Mediatek ISP P1 device driver

Tomasz Figa
2019-07-10T09:56:46Z

Hi Jungo,

On Tue, Jun 11, 2019 at 11:53:42AM +0800, Jungo Lin wrote:
> This patch adds the Mediatek ISP P1 HW control device driver.
> It handles the ISP HW configuration, provides interrupt handling and
> initializes the V4L2 device nodes and other functions.
>
> (The current metadata interface used in meta input and partial
> meta nodes is only a temporary solution to kick off the driver
> development and is not ready to be reviewed yet.)
>
> Signed-off-by: Jungo Lin <jungo.lin@mediatek.com>
> ---
> .../platform/mtk-isp/isp_50/cam/Makefile | 1 +
> .../mtk-isp/isp_50/cam/mtk_cam-regs.h | 126 ++
> .../platform/mtk-isp/isp_50/cam/mtk_cam.c | 1087 +++++++++++++++++
> .../platform/mtk-isp/isp_50/cam/mtk_cam.h | 243 ++++
> 4 files changed, 1457 insertions(+)
> create mode 100644 drivers/media/platform/mtk-isp/isp_50/cam/mtk_cam-regs.h
> create mode 100644 drivers/media/platform/mtk-isp/isp_50/cam/mtk_cam.c
> create mode 100644 drivers/media/platform/mtk-isp/isp_50/cam/mtk_cam.h
>

Thanks for the patch! Please see my comments inline.

[snip]

> diff --git a/drivers/media/platform/mtk-isp/isp_50/cam/mtk_cam-regs.h b/drivers/media/platform/mtk-isp/isp_50/cam/mtk_cam-regs.h
> new file mode 100644
> index 000000000000..9e59a6bfc6b7
> --- /dev/null
> +++ b/drivers/media/platform/mtk-isp/isp_50/cam/mtk_cam-regs.h
> @@ -0,0 +1,126 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (c) 2018 MediaTek Inc.
> + */
> +
> +#ifndef _CAM_REGS_H
> +#define _CAM_REGS_H
> +
> +/* TG Bit Mask */
> +#define VFDATA_EN_BIT BIT(0)
> +#define CMOS_EN_BIT BIT(0)
> +
> +/* normal signal bit */
> +#define VS_INT_ST BIT(0)
> +#define HW_PASS1_DON_ST BIT(11)
> +#define SOF_INT_ST BIT(12)
> +#define SW_PASS1_DON_ST BIT(30)
> +
> +/* err status bit */
> +#define TG_ERR_ST BIT(4)
> +#define TG_GBERR_ST BIT(5)
> +#define CQ_CODE_ERR_ST BIT(6)
> +#define CQ_APB_ERR_ST BIT(7)
> +#define CQ_VS_ERR_ST BIT(8)
> +#define AMX_ERR_ST BIT(15)
> +#define RMX_ERR_ST BIT(16)
> +#define BMX_ERR_ST BIT(17)
> +#define RRZO_ERR_ST BIT(18)
> +#define AFO_ERR_ST BIT(19)
> +#define IMGO_ERR_ST BIT(20)
> +#define AAO_ERR_ST BIT(21)
> +#define PSO_ERR_ST BIT(22)
> +#define LCSO_ERR_ST BIT(23)
> +#define BNR_ERR_ST BIT(24)
> +#define LSCI_ERR_ST BIT(25)
> +#define DMA_ERR_ST BIT(29)
> +
> +/* CAM DMA done status */
> +#define FLKO_DONE_ST BIT(4)
> +#define AFO_DONE_ST BIT(5)
> +#define AAO_DONE_ST BIT(7)
> +#define PSO_DONE_ST BIT(14)
> +
> +/* IRQ signal mask */
> +#define INT_ST_MASK_CAM ( \
> + VS_INT_ST |\
> + SOF_INT_ST |\
> + HW_PASS1_DON_ST |\
> + SW_PASS1_DON_ST)
> +
> +/* IRQ Error Mask */
> +#define INT_ST_MASK_CAM_ERR ( \
> + TG_ERR_ST |\
> + TG_GBERR_ST |\
> + CQ_CODE_ERR_ST |\
> + CQ_APB_ERR_ST |\
> + CQ_VS_ERR_ST |\
> + BNR_ERR_ST |\
> + RMX_ERR_ST |\
> + BMX_ERR_ST |\
> + BNR_ERR_ST |\
> + LSCI_ERR_ST |\
> + DMA_ERR_ST)
> +
> +/* IRQ Signal Log Mask */
> +#define INT_ST_LOG_MASK_CAM ( \
> + SOF_INT_ST |\
> + SW_PASS1_DON_ST |\
> + HW_PASS1_DON_ST |\
> + VS_INT_ST |\
> + TG_ERR_ST |\
> + TG_GBERR_ST |\
> + RRZO_ERR_ST |\
> + AFO_ERR_ST |\
> + IMGO_ERR_ST |\
> + AAO_ERR_ST |\
> + DMA_ERR_ST)
> +
> +/* DMA Event Notification Mask */
> +#define DMA_ST_MASK_CAM ( \
> + AAO_DONE_ST |\
> + AFO_DONE_ST)

Could we define the values next to the addresses of registers they apply to?
Also without the _BIT suffix and with the values prefixed with register
names. For example:

#define REG_TG_SEN_MODE 0x0230
#define TG_SEN_MODE_CMOS_EN BIT(0)

#define REG_TG_VF_CON 0x0234
#define TG_VF_CON_VFDATA_EN BIT(0)

> +
> +/* Status check */
> +#define REG_CTL_EN 0x0004
> +#define REG_CTL_DMA_EN 0x0008
> +#define REG_CTL_FMT_SEL 0x0010
> +#define REG_CTL_EN2 0x0018
> +#define REG_CTL_RAW_INT_EN 0x0020
> +#define REG_CTL_RAW_INT_STAT 0x0024
> +#define REG_CTL_RAW_INT2_STAT 0x0034
> +
> +#define REG_TG_SEN_MODE 0x0230
> +#define REG_TG_VF_CON 0x0234
> +
> +#define REG_IMGO_BASE_ADDR 0x1020
> +#define REG_RRZO_BASE_ADDR 0x1050
> +
> +/* Error status log */
> +#define REG_IMGO_ERR_STAT 0x1360
> +#define REG_RRZO_ERR_STAT 0x1364
> +#define REG_AAO_ERR_STAT 0x1368
> +#define REG_AFO_ERR_STAT 0x136c
> +#define REG_LCSO_ERR_STAT 0x1370
> +#define REG_UFEO_ERR_STAT 0x1374
> +#define REG_PDO_ERR_STAT 0x1378
> +#define REG_BPCI_ERR_STAT 0x137c
> +#define REG_LSCI_ERR_STAT 0x1384
> +#define REG_PDI_ERR_STAT 0x138c
> +#define REG_LMVO_ERR_STAT 0x1390
> +#define REG_FLKO_ERR_STAT 0x1394
> +#define REG_PSO_ERR_STAT 0x13a0
> +
> +/* ISP command */
> +#define REG_CQ_THR0_BASEADDR 0x0198
> +#define REG_HW_FRAME_NUM 0x13b8
> +
> +/* META */
> +#define REG_META0_VB2_INDEX 0x14dc
> +#define REG_META1_VB2_INDEX 0x151c

I don't believe these registers are really for VB2 indexes.

> +
> +/* FBC */
> +#define REG_AAO_FBC_STATUS 0x013c
> +#define REG_AFO_FBC_STATUS 0x0134
> +
> +#endif /* _CAM_REGS_H */
> diff --git a/drivers/media/platform/mtk-isp/isp_50/cam/mtk_cam.c b/drivers/media/platform/mtk-isp/isp_50/cam/mtk_cam.c
> new file mode 100644
> index 000000000000..c5a3babed69d
> --- /dev/null
> +++ b/drivers/media/platform/mtk-isp/isp_50/cam/mtk_cam.c
> @@ -0,0 +1,1087 @@
> +// SPDX-License-Identifier: GPL-2.0
> +//
> +// Copyright (c) 2018 MediaTek Inc.
> +
> +#include <linux/atomic.h>
> +#include <linux/cdev.h>
> +#include <linux/compat.h>
> +#include <linux/fs.h>
> +#include <linux/interrupt.h>
> +#include <linux/jiffies.h>
> +#include <linux/kernel.h>
> +#include <linux/ktime.h>
> +#include <linux/module.h>
> +#include <linux/of_platform.h>
> +#include <linux/of_irq.h>
> +#include <linux/of_address.h>
> +#include <linux/platform_device.h>
> +#include <linux/platform_data/mtk_scp.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/remoteproc.h>
> +#include <linux/sched/clock.h>
> +#include <linux/spinlock.h>
> +#include <linux/types.h>
> +#include <linux/videodev2.h>
> +#include <linux/vmalloc.h>
> +#include <media/v4l2-event.h>
> +
> +#include "mtk_cam.h"
> +#include "mtk_cam-regs.h"
> +#include "mtk_cam-smem.h"
> +
> +static const struct of_device_id mtk_isp_of_ids[] = {
> + {.compatible = "mediatek,mt8183-camisp",},
> + {}
> +};
> +MODULE_DEVICE_TABLE(of, mtk_isp_of_ids);

Please move below. Just above the platform_driver struct where it's used.

> +
> +/* List of clocks required by isp cam */
> +static const char * const mtk_isp_clks[] = {
> + "camsys_cam_cgpdn", "camsys_camtg_cgpdn"
> +};

Please move inside mtk_isp_probe, as a static const local variable. That
could also let you shorten the name, to clk_names for example.

> +
> +static void isp_dump_dma_status(struct isp_device *isp_dev)
> +{
> + dev_err(isp_dev->dev,
> + "IMGO:0x%x, RRZO:0x%x, AAO=0x%x, AFO=0x%x, LMVO=0x%x\n",
> + readl(isp_dev->regs + REG_IMGO_ERR_STAT),
> + readl(isp_dev->regs + REG_RRZO_ERR_STAT),
> + readl(isp_dev->regs + REG_AAO_ERR_STAT),
> + readl(isp_dev->regs + REG_AFO_ERR_STAT),
> + readl(isp_dev->regs + REG_LMVO_ERR_STAT));
> + dev_err(isp_dev->dev,
> + "LCSO=0x%x, PSO=0x%x, FLKO=0x%x, BPCI:0x%x, LSCI=0x%x\n",
> + readl(isp_dev->regs + REG_LCSO_ERR_STAT),
> + readl(isp_dev->regs + REG_PSO_ERR_STAT),
> + readl(isp_dev->regs + REG_FLKO_ERR_STAT),
> + readl(isp_dev->regs + REG_BPCI_ERR_STAT),
> + readl(isp_dev->regs + REG_LSCI_ERR_STAT));
> +}
> +
> +static void mtk_cam_dev_event_frame_sync(struct mtk_cam_dev *cam_dev,
> + __u32 frame_seq_no)
> +{
> + struct v4l2_event event;
> +
> + memset(&event, 0, sizeof(event));
> + event.type = V4L2_EVENT_FRAME_SYNC;
> + event.u.frame_sync.frame_sequence = frame_seq_no;

nit: You can just initialize the structure in the declaration.

> + v4l2_event_queue(cam_dev->subdev.devnode, &event);
> +}
> +
> +static void mtk_cam_dev_job_finish(struct mtk_isp_p1_ctx *isp_ctx,
> + unsigned int request_fd,
> + unsigned int frame_seq_no,
> + struct list_head *list_buf,
> + enum vb2_buffer_state state)
> +{
> + struct isp_p1_device *p1_dev = p1_ctx_to_dev(isp_ctx);
> + struct mtk_cam_dev *cam_dev = &p1_dev->cam_dev;
> + struct mtk_cam_dev_buffer *buf, *b0;
> + u64 timestamp;

Too many spaces between u64 and timestamp.

> +
> + if (!cam_dev->streaming)
> + return;
> +
> + dev_dbg(&p1_dev->pdev->dev, "%s request fd:%d frame_seq:%d state:%d\n",
> + __func__, request_fd, frame_seq_no, state);
> +
> + /*
> + * Set the buffer's VB2 status so that the user can dequeue
> + * the buffer.
> + */
> + timestamp = ktime_get_ns();
> + list_for_each_entry_safe(buf, b0, list_buf, list) {

nit: s/b0/buf_prev/

> + list_del(&buf->list);
> + buf->vbb.vb2_buf.timestamp = timestamp;
> + buf->vbb.sequence = frame_seq_no;
> + if (buf->vbb.vb2_buf.state == VB2_BUF_STATE_ACTIVE)

Any buffer that is not active shouldn't be on this list. If it is then it's
a bug somewhere else in the driver. Could be possibly related to the request
handling issues I pointed out in another comment.

> + vb2_buffer_done(&buf->vbb.vb2_buf, state);
> + }
> +}
> +
> +static void isp_deque_frame(struct isp_p1_device *p1_dev,

dequeue

> + unsigned int node_id, int vb2_index,
> + int frame_seq_no)
> +{
> + struct mtk_cam_dev *cam_dev = &p1_dev->cam_dev;
> + struct device *dev = &p1_dev->pdev->dev;
> + struct mtk_cam_video_device *node = &cam_dev->vdev_nodes[node_id];
> + struct mtk_cam_dev_buffer *b, *b0;
> + struct vb2_buffer *vb;
> +
> + if (!cam_dev->vdev_nodes[node_id].enabled || !cam_dev->streaming)
> + return;
> +
> + spin_lock(&node->slock);
> + b = list_first_entry(&node->pending_list,
> + struct mtk_cam_dev_buffer,
> + list);
> + list_for_each_entry_safe(b, b0, &node->pending_list, list) {
> + vb = &b->vbb.vb2_buf;
> + if (!vb->vb2_queue->uses_requests &&
> + vb->index == vb2_index &&
> + vb->state == VB2_BUF_STATE_ACTIVE) {
> + dev_dbg(dev, "%s:%d:%d", __func__, node_id, vb2_index);
> + vb->timestamp = ktime_get_ns();
> + b->vbb.sequence = frame_seq_no;
> + vb2_buffer_done(vb, VB2_BUF_STATE_DONE);
> + list_del(&b->list);
> + break;
> + }
> + }
> + spin_unlock(&node->slock);
> +}
> +
> +static void isp_deque_request_frame(struct isp_p1_device *p1_dev,

dequeue

> + int frame_seq_no)
> +{
> + struct mtk_isp_p1_ctx *isp_ctx = &p1_dev->isp_ctx;
> + struct device *dev = &p1_dev->pdev->dev;
> + struct mtk_isp_queue_job *framejob, *tmp;
> + struct isp_queue *p1_enqueue_list = &isp_ctx->p1_enqueue_list;
> +
> + /* Match dequeue work and enqueue frame */
> + spin_lock(&p1_enqueue_list->lock);
> + list_for_each_entry_safe(framejob, tmp, &p1_enqueue_list->queue,
> + list_entry) {
> + dev_dbg(dev,
> + "%s frame_seq_no:%d, target frame_seq_no:%d\n",
> + __func__,
> + framejob->frame_seq_no, frame_seq_no);
> + /* Match by the en-queued request number */
> + if (framejob->frame_seq_no == frame_seq_no) {
> + /* Pass to user space */
> + mtk_cam_dev_job_finish(isp_ctx,
> + framejob->request_fd,
> + framejob->frame_seq_no,
> + &framejob->list_buf,
> + VB2_BUF_STATE_DONE);
> + atomic_dec(&p1_enqueue_list->queue_cnt);
> + dev_dbg(dev,
> + "frame_seq_no:%d is done, queue_cnt:%d\n",
> + framejob->frame_seq_no,
> + atomic_read(&p1_enqueue_list->queue_cnt));
> +
> + /* Remove only when frame ready */
> + list_del(&framejob->list_entry);
> + kfree(framejob);
> + break;
> + } else if (framejob->frame_seq_no < frame_seq_no) {
> + /* Pass to user space for frame drop */
> + mtk_cam_dev_job_finish(isp_ctx,
> + framejob->request_fd,
> + framejob->frame_seq_no,
> + &framejob->list_buf,
> + VB2_BUF_STATE_ERROR);
> + atomic_dec(&p1_enqueue_list->queue_cnt);
> + dev_warn(dev,
> + "frame_seq_no:%d drop, queue_cnt:%d\n",
> + framejob->frame_seq_no,
> + atomic_read(&p1_enqueue_list->queue_cnt));
> +
> + /* Remove only drop frame */
> + list_del(&framejob->list_entry);
> + kfree(framejob);
> + } else {
> + break;
> + }
> + }
> + spin_unlock(&p1_enqueue_list->lock);
> +}
> +
> +static int isp_deque_work(void *data)

dequeue

> +{
> + struct isp_p1_device *p1_dev = (struct isp_p1_device *)data;
> + struct mtk_isp_p1_ctx *isp_ctx = &p1_dev->isp_ctx;
> + struct mtk_cam_dev_stat_event_data event_data;
> + atomic_t *irq_data_end = &isp_ctx->irq_data_end;
> + atomic_t *irq_data_start = &isp_ctx->irq_data_start;
> + unsigned long flags;
> + int ret, i;
> +
> + while (1) {
> + ret = wait_event_interruptible(isp_ctx->isp_deque_thread.wq,
> + (atomic_read(irq_data_end) !=
> + atomic_read(irq_data_start)) ||
> + kthread_should_stop());
> +
> + if (kthread_should_stop())
> + break;
> +
> + spin_lock_irqsave(&isp_ctx->irq_dequeue_lock, flags);
> + i = atomic_read(&isp_ctx->irq_data_start);
> + memcpy(&event_data, &isp_ctx->irq_event_datas[i],
> + sizeof(event_data));
> + atomic_set(&isp_ctx->irq_data_start, ++i & 0x3);
> + spin_unlock_irqrestore(&isp_ctx->irq_dequeue_lock, flags);
> +
> + if (event_data.irq_status_mask & HW_PASS1_DON_ST &&
> + event_data.dma_status_mask & AAO_DONE_ST) {
> + isp_deque_frame(p1_dev,
> + MTK_CAM_P1_META_OUT_0,
> + event_data.meta0_vb2_index,
> + event_data.frame_seq_no);
> + }
> + if (event_data.dma_status_mask & AFO_DONE_ST) {
> + isp_deque_frame(p1_dev,
> + MTK_CAM_P1_META_OUT_1,
> + event_data.meta1_vb2_index,
> + event_data.frame_seq_no);
> + }
> + if (event_data.irq_status_mask & SW_PASS1_DON_ST) {
> + isp_deque_frame(p1_dev,
> + MTK_CAM_P1_META_OUT_0,
> + event_data.meta0_vb2_index,
> + event_data.frame_seq_no);
> + isp_deque_frame(p1_dev,
> + MTK_CAM_P1_META_OUT_1,
> + event_data.meta1_vb2_index,
> + event_data.frame_seq_no);
> + isp_deque_request_frame(p1_dev,
> + event_data.frame_seq_no);
> + }
> + }
> +
> + return 0;
> +}
> +
> +static int irq_handle_sof(struct isp_device *isp_dev,
> + dma_addr_t base_addr,
> + unsigned int frame_num)
> +{
> + unsigned int addr_offset;
> + struct isp_p1_device *p1_dev = get_p1_device(isp_dev->dev);
> + int cq_num = atomic_read(&p1_dev->isp_ctx.composed_frame_id);
> +
> + isp_dev->sof_count += 1;
> +
> + if (cq_num <= frame_num) {
> + dev_dbg(isp_dev->dev,
> + "SOF_INT_ST, wait next, cq_num:%d, frame_num:%d",
> + cq_num, frame_num);
> + atomic_set(&p1_dev->isp_ctx.composing_frame, 0);
> + return cq_num;
> + }
> + atomic_set(&p1_dev->isp_ctx.composing_frame, cq_num - frame_num);
> +
> + addr_offset = CQ_ADDRESS_OFFSET * (frame_num % CQ_BUFFER_COUNT);
> + writel(base_addr + addr_offset, isp_dev->regs + REG_CQ_THR0_BASEADDR);
> + dev_dbg(isp_dev->dev,
> + "SOF_INT_ST, update next, cq_num:%d, frame_num:%d cq_addr:0x%x",
> + cq_num, frame_num, addr_offset);
> +
> + return cq_num;
> +}
> +
> +static void irq_handle_notify_event(struct isp_device *isp_dev,
> + unsigned int irq_status,
> + unsigned int dma_status,
> + bool sof_only)
> +{
> + struct isp_p1_device *p1_dev = get_p1_device(isp_dev->dev);
> + struct mtk_isp_p1_ctx *isp_ctx = &p1_dev->isp_ctx;
> + struct device *dev = isp_dev->dev;
> + unsigned long flags;
> + int i;
> +
> + if (irq_status & VS_INT_ST) {
> + /* Notify specific HW events to user space */
> + mtk_cam_dev_event_frame_sync(&p1_dev->cam_dev,
> + isp_dev->current_frame);

Shouldn't we call this at SOF_INT_ST and not VS? At least according to the
definition of the V4L2_EVENT_FRAME_SYNC event at
https://www.kernel.org/doc/html/latest/media/uapi/v4l/vidioc-dqevent.html

> + dev_dbg(dev,
> + "frame sync is sent:%d:%d\n",
> + isp_dev->sof_count,
> + isp_dev->current_frame);
> + if (sof_only)
> + return;

If this function can be called only to perform this block, perhaps it should
be split into two functions?

Also, what happens if we get sof_only, but we don't get VS_INT_ST set in
irq_status? Is it expected that in such case the other part of the function
is executed?

> + }
> +
> + if (irq_status & SW_PASS1_DON_ST) {
> + /* Notify TX thread to send if TX frame is blocked */
> + wake_up_interruptible(&isp_ctx->composer_tx_thread.wq);
> + }
> +
> + spin_lock_irqsave(&isp_ctx->irq_dequeue_lock, flags);
> + i = atomic_read(&isp_ctx->irq_data_end);
> + isp_ctx->irq_event_datas[i].frame_seq_no = isp_dev->current_frame;
> + isp_ctx->irq_event_datas[i].meta0_vb2_index = isp_dev->meta0_vb2_index;
> + isp_ctx->irq_event_datas[i].meta1_vb2_index = isp_dev->meta1_vb2_index;
> + isp_ctx->irq_event_datas[i].irq_status_mask =
> + (irq_status & INT_ST_MASK_CAM);
> + isp_ctx->irq_event_datas[i].dma_status_mask =
> + (dma_status & DMA_ST_MASK_CAM);
> + atomic_set(&isp_ctx->irq_data_end, ++i & 0x3);
> + spin_unlock_irqrestore(&isp_ctx->irq_dequeue_lock, flags);
> +
> + wake_up_interruptible(&isp_ctx->isp_deque_thread.wq);

I can see that all isp_deque_work() does is returning buffers to vb2. I
don't think we need this intricate system to do that, as we could just do
it inside the interrupt handler, in isp_irq_cam() directly.

> +
> + dev_dbg(dev,
> + "%s IRQ:0x%x DMA:0x%x seq:%d idx0:%d idx1:%d\n",
> + __func__,
> + (irq_status & INT_ST_MASK_CAM),
> + (dma_status & DMA_ST_MASK_CAM),
> + isp_dev->current_frame,
> + isp_dev->meta0_vb2_index,
> + isp_dev->meta1_vb2_index);
> +}
> +
> +irqreturn_t isp_irq_cam(int irq, void *data)
> +{
> + struct isp_device *isp_dev = (struct isp_device *)data;
> + struct isp_p1_device *p1_dev = get_p1_device(isp_dev->dev);
> + struct mtk_isp_p1_ctx *isp_ctx = &p1_dev->isp_ctx;
> + struct device *dev = isp_dev->dev;
> + unsigned int cam_idx, cq_num, hw_frame_num;
> + unsigned int meta0_vb2_index, meta1_vb2_index;
> + unsigned int irq_status, err_status, dma_status;
> + unsigned int aao_fbc, afo_fbc;
> + unsigned long flags;
> +
> + /* Check the streaming is off or not */
> + if (!p1_dev->cam_dev.streaming)
> + return IRQ_HANDLED;

This shouldn't be needed. The driver needs to unmask the interrupts in
hardware registers when it starts streaming and mask them when it stops.
Note that I mean the P1 hardware registers, not disable_irq(), which
shouldn't be used.

> +
> + cam_idx = isp_dev->isp_hw_module - ISP_CAM_A_IDX;
> + cq_num = 0;
> +
> + spin_lock_irqsave(&isp_dev->spinlock_irq, flags);
> + irq_status = readl(isp_dev->regs + REG_CTL_RAW_INT_STAT);
> + dma_status = readl(isp_dev->regs + REG_CTL_RAW_INT2_STAT);
> + hw_frame_num = readl(isp_dev->regs + REG_HW_FRAME_NUM);
> + meta0_vb2_index = readl(isp_dev->regs + REG_META0_VB2_INDEX);
> + meta1_vb2_index = readl(isp_dev->regs + REG_META1_VB2_INDEX);

Hmm, reading vb2 buffer index from hardware registers? Was this hardware
designed exclusively for V4L2? ;)

Jokes aside, how does the hardware know V4L2 buffer indexes?

> + aao_fbc = readl(isp_dev->regs + REG_AAO_FBC_STATUS);
> + afo_fbc = readl(isp_dev->regs + REG_AFO_FBC_STATUS);
> + spin_unlock_irqrestore(&isp_dev->spinlock_irq, flags);
> +
> + /* Ignore unnecessary IRQ */
> + if (!irq_status && (!(dma_status & DMA_ST_MASK_CAM)))
> + return IRQ_HANDLED;

Unnecessary IRQs should be masked in the hardware IRQ mask registers. If we
get an interrupt without any unmasked hardware IRQs active in the status,
that's an error somewhere and we should return IRQ_NONE.

> +
> + err_status = irq_status & INT_ST_MASK_CAM_ERR;
> +
> + /* Sof, done order check */
> + if ((irq_status & SOF_INT_ST) && (irq_status & HW_PASS1_DON_ST)) {
> + dev_dbg(dev, "sof_done block cnt:%d\n", isp_dev->sof_count);
> +
> + /* Notify IRQ event and enqueue frame */
> + irq_handle_notify_event(isp_dev, irq_status, dma_status, 0);
> + isp_dev->current_frame = hw_frame_num;

What exactly is hw_frame_num? Shouldn't we assign it before notifying the
event?

> + isp_dev->meta0_vb2_index = meta0_vb2_index;
> + isp_dev->meta1_vb2_index = meta1_vb2_index;
> + } else {
> + if (irq_status & SOF_INT_ST) {
> + isp_dev->current_frame = hw_frame_num;
> + isp_dev->meta0_vb2_index = meta0_vb2_index;
> + isp_dev->meta1_vb2_index = meta1_vb2_index;
> + }
> + irq_handle_notify_event(isp_dev, irq_status, dma_status, 1);
> + }

The if and else blocks do almost the same things just in different order. Is
it really expected?

> +
> + if (irq_status & SOF_INT_ST)
> + cq_num = irq_handle_sof(isp_dev, isp_ctx->scp_mem_iova,
> + hw_frame_num);
> +
> + /* Check ISP error status */
> + if (err_status) {
> + dev_err(dev,
> + "raw_int_err:0x%x/0x%x\n",
> + irq_status, err_status);
> + /* Show DMA errors in detail */
> + if (err_status & DMA_ERR_ST)
> + isp_dump_dma_status(isp_dev);
> + }
> +
> + if (irq_status & INT_ST_LOG_MASK_CAM)
> + dev_dbg(dev, IRQ_STAT_STR,

Please just put that string here, otherwise the reader would have no idea
what message is being printed here.

> + 'A' + cam_idx,
> + isp_dev->sof_count,
> + irq_status,
> + dma_status,
> + hw_frame_num,
> + cq_num,
> + aao_fbc,
> + afo_fbc);

nit: No need to put each argument in its own line.

> +
> + return IRQ_HANDLED;
> +}
> +
> +static int isp_setup_scp_rproc(struct isp_p1_device *p1_dev)
> +{
> + phandle rproc_phandle;
> + struct device *dev = &p1_dev->pdev->dev;
> + int ret;
> +
> + p1_dev->scp_pdev = scp_get_pdev(p1_dev->pdev);
> + if (!p1_dev->scp_pdev) {
> + dev_err(dev, "Failed to get scp device\n");
> + return -ENODEV;
> + }
> +
> + ret = of_property_read_u32(dev->of_node, "mediatek,scp",
> + &rproc_phandle);
> + if (ret) {
> + dev_err(dev, "fail to get rproc_phandle:%d\n", ret);
> + return -EINVAL;
> + }
> +
> + p1_dev->rproc_handle = rproc_get_by_phandle(rproc_phandle);
> + dev_dbg(dev, "p1 rproc_phandle: 0x%pK\n\n", p1_dev->rproc_handle);
> + if (!p1_dev->rproc_handle) {
> + dev_err(dev, "fail to get rproc_handle\n");
> + return -EINVAL;
> + }

This look-up should be done once in probe(). Only the rproc_boot() should
happen dynamically.

> +
> + ret = rproc_boot(p1_dev->rproc_handle);
> + if (ret) {
> + /*
> + * Return 0 if downloading firmware successfully,
> + * otherwise it is failed
> + */
> + return -ENODEV;
> + }
> +
> + return 0;
> +}
> +
> +static int isp_init_context(struct isp_p1_device *p1_dev)
> +{
> + struct mtk_isp_p1_ctx *isp_ctx = &p1_dev->isp_ctx;
> + struct device *dev = &p1_dev->pdev->dev;
> + unsigned int i;
> +
> + dev_dbg(dev, "init irq work thread\n");
> + if (!isp_ctx->isp_deque_thread.thread) {
> + init_waitqueue_head(&isp_ctx->isp_deque_thread.wq);
> + isp_ctx->isp_deque_thread.thread =
> + kthread_run(isp_deque_work, (void *)p1_dev,
> + "isp_deque_work");
> + if (IS_ERR(isp_ctx->isp_deque_thread.thread)) {
> + dev_err(dev, "unable to alloc kthread\n");
> + isp_ctx->isp_deque_thread.thread = NULL;
> + return -ENOMEM;
> + }
> + }
> + spin_lock_init(&isp_ctx->irq_dequeue_lock);
> + mutex_init(&isp_ctx->lock);
> +
> + INIT_LIST_HEAD(&isp_ctx->p1_enqueue_list.queue);
> + atomic_set(&isp_ctx->p1_enqueue_list.queue_cnt, 0);
> +
> + for (i = 0; i < ISP_DEV_NODE_NUM; i++)
> + spin_lock_init(&p1_dev->isp_devs[i].spinlock_irq);
> +
> + spin_lock_init(&isp_ctx->p1_enqueue_list.lock);
> + spin_lock_init(&isp_ctx->composer_txlist.lock);
> +
> + atomic_set(&isp_ctx->irq_data_end, 0);
> + atomic_set(&isp_ctx->irq_data_start, 0);
> +
> + return 0;

Everything here looks like something that should be done once in probe. I
also don't see a point of having a separate mtk_isp_p1_ctx struct for the
data above. It could be just located in p1_dev, at least for now.

If we end up implementing support for multiple contexts, we could isolate
per-context data then, once we know what's really per-context. For now,
let's keep it simple.

> +}
> +
> +static int isp_uninit_context(struct device *dev)
> +{
> + struct isp_p1_device *p1_dev = get_p1_device(dev);
> + struct mtk_isp_p1_ctx *isp_ctx = &p1_dev->isp_ctx;
> + struct mtk_isp_queue_job *framejob, *tmp_framejob;
> +
> + spin_lock_irq(&isp_ctx->p1_enqueue_list.lock);
> + list_for_each_entry_safe(framejob, tmp_framejob,
> + &isp_ctx->p1_enqueue_list.queue, list_entry) {
> + list_del(&framejob->list_entry);
> + kfree(framejob);
> + }
> + spin_unlock_irq(&isp_ctx->p1_enqueue_list.lock);
> +
> + if (isp_ctx->isp_deque_thread.thread) {
> + kthread_stop(isp_ctx->isp_deque_thread.thread);
> + wake_up_interruptible(&isp_ctx->isp_deque_thread.wq);
> + isp_ctx->isp_deque_thread.thread = NULL;
> + }
> +
> + mutex_destroy(&isp_ctx->lock);
> +
> + return 0;
> +}
> +
> +static unsigned int get_enabled_dma_ports(struct mtk_cam_dev *cam_dev)
> +{
> + unsigned int enabled_dma_ports, i;
> +
> + /* Get the enabled meta DMA ports */
> + enabled_dma_ports = 0;
> +
> + for (i = 0; i < MTK_CAM_P1_TOTAL_NODES; i++)
> + if (cam_dev->vdev_nodes[i].enabled)
> + enabled_dma_ports |=
> + cam_dev->vdev_nodes[i].desc.dma_port;
> +
> + dev_dbg(&cam_dev->pdev->dev, "%s :0x%x", __func__, enabled_dma_ports);
> +
> + return enabled_dma_ports;
> +}
> +
> +/* Utility functions */
> +static unsigned int get_sensor_pixel_id(unsigned int fmt)
> +{
> + switch (fmt) {
> + case MEDIA_BUS_FMT_SBGGR8_1X8:
> + case MEDIA_BUS_FMT_SBGGR10_1X10:
> + case MEDIA_BUS_FMT_SBGGR12_1X12:
> + case MEDIA_BUS_FMT_SBGGR14_1X14:
> + return RAW_PXL_ID_B;
> + case MEDIA_BUS_FMT_SGBRG8_1X8:
> + case MEDIA_BUS_FMT_SGBRG10_1X10:
> + case MEDIA_BUS_FMT_SGBRG12_1X12:
> + case MEDIA_BUS_FMT_SGBRG14_1X14:
> + return RAW_PXL_ID_GB;
> + case MEDIA_BUS_FMT_SGRBG8_1X8:
> + case MEDIA_BUS_FMT_SGRBG10_1X10:
> + case MEDIA_BUS_FMT_SGRBG12_1X12:
> + case MEDIA_BUS_FMT_SGRBG14_1X14:
> + return RAW_PXL_ID_GR;
> + case MEDIA_BUS_FMT_SRGGB8_1X8:
> + case MEDIA_BUS_FMT_SRGGB10_1X10:
> + case MEDIA_BUS_FMT_SRGGB12_1X12:
> + case MEDIA_BUS_FMT_SRGGB14_1X14:
> + return RAW_PXL_ID_R;
> + default:

Could we fail here instead?

> + return RAW_PXL_ID_B;
> + }
> +}
> +
> +static unsigned int get_sensor_fmt(unsigned int fmt)
> +{
> + switch (fmt) {
> + case MEDIA_BUS_FMT_SBGGR8_1X8:
> + case MEDIA_BUS_FMT_SGBRG8_1X8:
> + case MEDIA_BUS_FMT_SGRBG8_1X8:
> + case MEDIA_BUS_FMT_SRGGB8_1X8:
> + return IMG_FMT_BAYER8;
> + case MEDIA_BUS_FMT_SBGGR10_1X10:
> + case MEDIA_BUS_FMT_SGBRG10_1X10:
> + case MEDIA_BUS_FMT_SGRBG10_1X10:
> + case MEDIA_BUS_FMT_SRGGB10_1X10:
> + return IMG_FMT_BAYER10;
> + case MEDIA_BUS_FMT_SBGGR12_1X12:
> + case MEDIA_BUS_FMT_SGBRG12_1X12:
> + case MEDIA_BUS_FMT_SGRBG12_1X12:
> + case MEDIA_BUS_FMT_SRGGB12_1X12:
> + return IMG_FMT_BAYER12;
> + case MEDIA_BUS_FMT_SBGGR14_1X14:
> + case MEDIA_BUS_FMT_SGBRG14_1X14:
> + case MEDIA_BUS_FMT_SGRBG14_1X14:
> + case MEDIA_BUS_FMT_SRGGB14_1X14:
> + return IMG_FMT_BAYER14;
> + default:
> + return IMG_FMT_UNKNOWN;
> + }
> +}
> +
> +static unsigned int get_img_fmt(unsigned int fourcc)
> +{
> + switch (fourcc) {
> + case V4L2_PIX_FMT_MTISP_B8:
> + return IMG_FMT_BAYER8;
> + case V4L2_PIX_FMT_MTISP_F8:
> + return IMG_FMT_FG_BAYER8;
> + case V4L2_PIX_FMT_MTISP_B10:
> + return IMG_FMT_BAYER10;
> + case V4L2_PIX_FMT_MTISP_F10:
> + return IMG_FMT_FG_BAYER10;
> + case V4L2_PIX_FMT_MTISP_B12:
> + return IMG_FMT_BAYER12;
> + case V4L2_PIX_FMT_MTISP_F12:
> + return IMG_FMT_FG_BAYER12;
> + case V4L2_PIX_FMT_MTISP_B14:
> + return IMG_FMT_BAYER14;
> + case V4L2_PIX_FMT_MTISP_F14:
> + return IMG_FMT_FG_BAYER14;
> + default:
> + return IMG_FMT_UNKNOWN;
> + }
> +}
> +
> +static unsigned int get_pixel_byte(unsigned int fourcc)
> +{
> + switch (fourcc) {
> + case V4L2_PIX_FMT_MTISP_B8:
> + case V4L2_PIX_FMT_MTISP_F8:
> + return 8;
> + case V4L2_PIX_FMT_MTISP_B10:
> + case V4L2_PIX_FMT_MTISP_F10:
> + return 10;
> + case V4L2_PIX_FMT_MTISP_B12:
> + case V4L2_PIX_FMT_MTISP_F12:
> + return 12;
> + case V4L2_PIX_FMT_MTISP_B14:
> + case V4L2_PIX_FMT_MTISP_F14:
> + return 14;
> + default:

Could we fail here instead, so that we don't mask some potential errors?

> + return 10;
> + }
> +}
> +
> +static void config_img_fmt(struct device *dev, struct p1_img_output *out_fmt,
> + const struct v4l2_format *in_fmt,
> + const struct v4l2_subdev_format *sd_format)
> +{
> + out_fmt->img_fmt = get_img_fmt(in_fmt->fmt.pix_mp.pixelformat);
> + out_fmt->pixel_byte = get_pixel_byte(in_fmt->fmt.pix_mp.pixelformat);
> + out_fmt->size.w = in_fmt->fmt.pix_mp.width;
> + out_fmt->size.h = in_fmt->fmt.pix_mp.height;
> +
> + out_fmt->size.stride = in_fmt->fmt.pix_mp.plane_fmt[0].bytesperline;
> + out_fmt->size.xsize = in_fmt->fmt.pix_mp.plane_fmt[0].bytesperline;

Please group operations on the same field together, i.e. remove the blank
line above size.stride and add one blank line above size.w.

> +
> + out_fmt->crop.left = 0x0;
> + out_fmt->crop.top = 0x0;
> +

Remove the blank line.

> + out_fmt->crop.width = sd_format->format.width;
> + out_fmt->crop.height = sd_format->format.height;
> +
> + WARN_ONCE(in_fmt->fmt.pix_mp.width > out_fmt->crop.width ||
> + in_fmt->fmt.pix_mp.height > out_fmt->crop.height,
> + "img out:%d:%d in:%d:%d",
> + in_fmt->fmt.pix_mp.width, in_fmt->fmt.pix_mp.height,
> + out_fmt->crop.width, out_fmt->crop.height);

We should check this earlier and fail the streaming start if there is a
mismatch between sensor and video node configuration.

> +
> + dev_dbg(dev, "pixel_byte:%d img_fmt:0x%x\n",
> + out_fmt->pixel_byte,
> + out_fmt->img_fmt);
> + dev_dbg(dev,
> + "param:size=%0dx%0d, stride:%d, xsize:%d, crop=%0dx%0d\n",
> + out_fmt->size.w, out_fmt->size.h,
> + out_fmt->size.stride, out_fmt->size.xsize,
> + out_fmt->crop.width, out_fmt->crop.height);
> +}
> +
> +/* ISP P1 interface functions */
> +int mtk_isp_power_init(struct mtk_cam_dev *cam_dev)
> +{
> + struct device *dev = &cam_dev->pdev->dev;
> + struct isp_p1_device *p1_dev = get_p1_device(dev);
> + struct mtk_isp_p1_ctx *isp_ctx = &p1_dev->isp_ctx;
> + int ret;
> +
> + ret = isp_setup_scp_rproc(p1_dev);
> + if (ret)
> + return ret;
> +
> + ret = isp_init_context(p1_dev);
> + if (ret)
> + return ret;

The above function doesn't really seem to be related to power management.
Should it be called from subdev stream on?

> +
> + ret = isp_composer_init(dev);
> + if (ret)
> + goto composer_err;

This also doesn't seem to be related to power management.

> +
> + pm_runtime_get_sync(dev);
> +
> + /* ISP HW INIT */
> + isp_ctx->isp_hw_module = ISP_CAM_B_IDX;

There is some amount of code handling various values of isp_hw_module in
this driver. If we're hardcoding ISP_CAM_B_IDX here, it's basically dead
code that can't be tested. Please either add support for all the indexes in
the driver or simplify all the code to just handle CAM_B.

> + /* Use pure RAW as default HW path */
> + isp_ctx->isp_raw_path = ISP_PURE_RAW_PATH;
> + atomic_set(&p1_dev->cam_dev.streamed_node_count, 0);
> +
> + isp_composer_hw_init(dev);
> + /* Check enabled DMAs which is configured by media setup */
> + isp_composer_meta_config(dev, get_enabled_dma_ports(cam_dev));

Hmm, this seems to be also configured by isp_compoer_hw_config(). Are both
necessary?

> +
> + dev_dbg(dev, "%s done\n", __func__);
> +
> + return 0;
> +
> +composer_err:
> + isp_uninit_context(dev);
> +
> + return ret;
> +}
> +
> +int mtk_isp_power_release(struct device *dev)
> +{
> + isp_composer_hw_deinit(dev);
> + isp_uninit_context(dev);

These two don't seem to be related to power either.

Instead, I don't see anything that could undo the rproc_boot() operation
here.

> +
> + dev_dbg(dev, "%s done\n", __func__);
> +
> + return 0;
> +}
> +
> +int mtk_isp_config(struct device *dev)
> +{
> + struct isp_p1_device *p1_dev = get_p1_device(dev);
> + struct mtk_isp_p1_ctx *isp_ctx = &p1_dev->isp_ctx;
> + struct p1_config_param config_param;
> + struct mtk_cam_dev *cam_dev = &p1_dev->cam_dev;
> + struct v4l2_subdev_format sd_fmt;
> + unsigned int enabled_dma_ports;
> + struct v4l2_format *img_fmt;
> + int ret;
> +
> + p1_dev->isp_devs[isp_ctx->isp_hw_module].current_frame = 0;
> + p1_dev->isp_devs[isp_ctx->isp_hw_module].sof_count = 0;
> +
> + isp_ctx->frame_seq_no = 1;
> + atomic_set(&isp_ctx->composed_frame_id, 0);
> +
> + /* Get the enabled DMA ports */
> + enabled_dma_ports = get_enabled_dma_ports(cam_dev);
> + dev_dbg(dev, "%s enable_dma_ports:0x%x", __func__, enabled_dma_ports);
> +
> + /* Sensor config */
> + sd_fmt.which = V4L2_SUBDEV_FORMAT_ACTIVE;
> + ret = v4l2_subdev_call(cam_dev->sensor, pad, get_fmt, NULL, &sd_fmt);
> +

Unnecessary blank line.

> + if (ret) {
> + dev_dbg(dev, "sensor g_fmt on failed:%d\n", ret);
> + return -EPERM;

return ret?

> + }
> +
> + dev_dbg(dev,
> + "get_fmt ret=%d, w=%d, h=%d, code=0x%x, field=%d, color=%d\n",
> + ret, sd_fmt.format.width, sd_fmt.format.height,
> + sd_fmt.format.code, sd_fmt.format.field,
> + sd_fmt.format.colorspace);
> +
> + config_param.cfg_in_param.continuous = 0x1;
> + config_param.cfg_in_param.subsample = 0x0;
> + /* Fix to one pixel mode in default */
> + config_param.cfg_in_param.pixel_mode = 0x1;
> + /* Support normal pattern in default */
> + config_param.cfg_in_param.data_pattern = 0x0;
> +
> + config_param.cfg_in_param.crop.left = 0x0;
> + config_param.cfg_in_param.crop.top = 0x0;

Why hexadecimal numerals? Also, what's the meaning of these values? For
anything boolean, you could just use true and false as a substite of 0 and
1. For anything that has more values, please define the values using macros.

> +
> + config_param.cfg_in_param.raw_pixel_id =
> + get_sensor_pixel_id(sd_fmt.format.code);
> + config_param.cfg_in_param.img_fmt = get_sensor_fmt(sd_fmt.format.code);
> + config_param.cfg_in_param.crop.width = sd_fmt.format.width;
> + config_param.cfg_in_param.crop.height = sd_fmt.format.height;

Move the other crop settings from above to here.

> +
> + config_param.cfg_main_param.bypass = 1;
> + img_fmt = &cam_dev->vdev_nodes[MTK_CAM_P1_MAIN_STREAM_OUT].vdev_fmt;
> + if ((enabled_dma_ports & R_IMGO) == R_IMGO) {

No need for the == R_IMGO part.

> + config_param.cfg_main_param.bypass = 0;
> + config_param.cfg_main_param.pure_raw = isp_ctx->isp_raw_path;
> + config_param.cfg_main_param.pure_raw_pack = 1;
> + config_img_fmt(dev, &config_param.cfg_main_param.output,
> + img_fmt, &sd_fmt);
> + }
> +
> + config_param.cfg_resize_param.bypass = 1;
> + img_fmt = &cam_dev->vdev_nodes[MTK_CAM_P1_PACKED_BIN_OUT].vdev_fmt;
> + if ((enabled_dma_ports & R_RRZO) == R_RRZO) {

Ditto.

> + config_param.cfg_resize_param.bypass = 0;
> + config_img_fmt(dev, &config_param.cfg_resize_param.output,
> + img_fmt, &sd_fmt);
> + }
> +
> + /* Configure meta DMAs info. */
> + config_param.cfg_meta_param.enabled_meta_dmas = enabled_dma_ports;

Should image DMAs be masked out of this bitmap?

> +
> + isp_composer_hw_config(dev, &config_param);
> +
> + dev_dbg(dev, "%s done\n", __func__);
> +
> + return 0;
> +}
> +
> +void mtk_isp_enqueue(struct device *dev, unsigned int dma_port,
> + struct mtk_cam_dev_buffer *buffer)
> +{
> + struct mtk_isp_scp_p1_cmd frameparams;
> +
> + memset(&frameparams, 0, sizeof(frameparams));
> + frameparams.cmd_id = ISP_CMD_ENQUEUE_META;
> + frameparams.meta_frame.enabled_dma = dma_port;
> + frameparams.meta_frame.vb_index = buffer->vbb.vb2_buf.index;
> + frameparams.meta_frame.meta_addr.iova = buffer->daddr;
> + frameparams.meta_frame.meta_addr.scp_addr = buffer->scp_addr;
> +
> + isp_composer_enqueue(dev, &frameparams, SCP_ISP_CMD);
> +}
> +
> +void mtk_isp_req_flush_buffers(struct device *dev)
> +{
> + struct isp_p1_device *p1_dev = get_p1_device(dev);
> + struct mtk_isp_queue_job *job, *j0;
> + struct mtk_cam_dev_buffer *buf, *b0;
> + struct isp_queue *p1_list = &p1_dev->isp_ctx.p1_enqueue_list;
> +
> + if (!atomic_read(&p1_list->queue_cnt))
> + return;

Do we need this explicit check? The code below wouldn't do anything if there
isn't anything in the list. IMHO we could even remove queue_cnt completely.

> +
> + spin_lock(&p1_list->lock);
> + list_for_each_entry_safe(job, j0, &p1_list->queue, list_entry) {

nit: s/j0/job_prev/

> + list_for_each_entry_safe(buf, b0, &job->list_buf, list) {

nit: s/b0/buf_pref/

Also, we should be able to replace this with iterating over the generic list
of request objects, rather than this internal list.

> + list_del(&buf->list);
> + if (buf->vbb.vb2_buf.state == VB2_BUF_STATE_ACTIVE)

It shouldn't be possible to happen. If you see this check failing, that
means a problem somewhere else in the driver.

> + vb2_buffer_done(&buf->vbb.vb2_buf,
> + VB2_BUF_STATE_ERROR);
> + }
> + list_del(&job->list_entry);
> + atomic_dec(&p1_list->queue_cnt);
> + kfree(job);
> + }
> + spin_unlock(&p1_list->lock);
> +}
> +
> +void mtk_isp_req_enqueue(struct device *dev, struct media_request *req)
> +{
> + struct isp_p1_device *p1_dev = get_p1_device(dev);

Just pass p1_dev to this function instead of dev.

> + struct mtk_isp_p1_ctx *isp_ctx = &p1_dev->isp_ctx;
> + struct p1_frame_param frameparams;
> + struct mtk_isp_queue_job *framejob;
> + struct media_request_object *obj, *obj_safe;
> + struct vb2_buffer *vb;
> + struct mtk_cam_dev_buffer *buf;
> +
> + framejob = kzalloc(sizeof(*framejob), GFP_ATOMIC);

This allocation shouldn't be needed. The structure should be already a part
of the mtk_cam_dev_request struct that wraps media_request. Actually. I'd
even say that the contents of this struct should be just moved to that one
to avoid overabstracting.

> + memset(framejob, 0, sizeof(*framejob));

Putting the above comment aside, kzalloc() already zeroes the memory.

> + memset(&frameparams, 0, sizeof(frameparams));
> + INIT_LIST_HEAD(&framejob->list_buf);
> +
> + frameparams.frame_seq_no = isp_ctx->frame_seq_no++;
> + frameparams.sof_idx =
> + p1_dev->isp_devs[isp_ctx->isp_hw_module].sof_count;

How is this synchronized with the sof_count increment in irq_handle_sof()?

> + framejob->frame_seq_no = frameparams.frame_seq_no;
> +
> + list_for_each_entry_safe(obj, obj_safe, &req->objects, list) {
> + vb = container_of(obj, struct vb2_buffer, req_obj);

We should check that the object type before assuming it's a vb2_buffer by
calling vb2_request_object_is_buffer().

> + buf = container_of(vb, struct mtk_cam_dev_buffer, vbb.vb2_buf);
> + framejob->request_fd = buf->vbb.request_fd;

We shouldn't use request_fd as the key here. We already have req here, which
is the right key to use.

That said, I can see framejob->request_fd only used for printing a debugging
message in mtk_cam_dev_job_finish(). The request API core should already
print something for us once a request is completed, so perhaps that isn't
needed?

> + frameparams.dma_buffers[buf->node_id].iova = buf->daddr;
> + frameparams.dma_buffers[buf->node_id].scp_addr = buf->scp_addr;
> + list_add_tail(&buf->list, &framejob->list_buf);

Why do we need this private list? We could just call exactly the same
list_for_each() over the request objects.

> + }
> +
> + spin_lock(&isp_ctx->p1_enqueue_list.lock);
> + list_add_tail(&framejob->list_entry, &isp_ctx->p1_enqueue_list.queue);

We already have a list head in mtk_cam_dev_request.

> + atomic_inc(&isp_ctx->p1_enqueue_list.queue_cnt);
> + spin_unlock(&isp_ctx->p1_enqueue_list.lock);
> +
> + isp_composer_enqueue(dev, &frameparams, SCP_ISP_FRAME);
> + dev_dbg(dev, "request fd:%d frame_seq_no:%d is queued cnt:%d\n",
> + framejob->request_fd,
> + frameparams.frame_seq_no,
> + atomic_read(&isp_ctx->p1_enqueue_list.queue_cnt));
> +}
> +
> +static int enable_sys_clock(struct isp_p1_device *p1_dev)
> +{
> + struct device *dev = &p1_dev->pdev->dev;
> + int ret;
> +
> + dev_info(dev, "- %s\n", __func__);

dev_dbg()

> +
> + ret = clk_bulk_prepare_enable(p1_dev->isp_ctx.num_clks,
> + p1_dev->isp_ctx.clk_list);
> + if (ret)
> + goto clk_err;
> +
> + return 0;
> +
> +clk_err:
> + dev_err(dev, "cannot pre-en isp_cam clock:%d\n", ret);
> + clk_bulk_disable_unprepare(p1_dev->isp_ctx.num_clks,
> + p1_dev->isp_ctx.clk_list);

clk_bulk_prepare_enable() returns without any clocks enabled if it fails, so
this would disable the clocks second time.

> + return ret;
> +}
> +
> +static void disable_sys_clock(struct isp_p1_device *p1_dev)
> +{
> + dev_info(&p1_dev->pdev->dev, "- %s\n", __func__);

dev_dbg()

> + clk_bulk_disable_unprepare(p1_dev->isp_ctx.num_clks,
> + p1_dev->isp_ctx.clk_list);
> +}

There is no point in having wrapper functions to just call one function
inside. Please just call clk_bulk_*() directly.

> +
> +static int mtk_isp_suspend(struct device *dev)
> +{
> + struct isp_p1_device *p1_dev = get_p1_device(dev);
> + int module = p1_dev->isp_ctx.isp_hw_module;
> + struct isp_device *isp_dev = &p1_dev->isp_devs[module];
> + unsigned int reg_val;
> +
> + dev_dbg(dev, "- %s\n", __func__);
> +

We need to check if the device isn't already runtime suspended. If it is, we
don't have to do anything here and can just return.

We also need to ensure that no new requests are queued to the hardware at
this point. This could be done by replacing any of the kthreads with
workqueues and making all of the workqueues freezable.

> + isp_dev = &p1_dev->isp_devs[module];
> + reg_val = readl(isp_dev->regs + REG_TG_VF_CON);
> + if (reg_val & VFDATA_EN_BIT) {
> + dev_dbg(dev, "Cam:%d suspend, disable VF\n", module);
> + /* Disable view finder */
> + writel((reg_val & (~VFDATA_EN_BIT)),
> + isp_dev->regs + REG_TG_VF_CON);
> + /*
> + * After VF enable, the TG frame count will be reset to 0;
> + */
> + reg_val = readl(isp_dev->regs + REG_TG_SEN_MODE);
> + writel((reg_val & (~CMOS_EN_BIT)),
> + isp_dev->regs + + REG_TG_SEN_MODE);
> + }

Are you sure this is the right handling? We need to make sure the hardware
finishes processing the current frame and stops.

> +
> + disable_sys_clock(p1_dev);
> +
> + return 0;
> +}
> +
> +static int mtk_isp_resume(struct device *dev)
> +{
> + struct isp_p1_device *p1_dev = get_p1_device(dev);
> + int module = p1_dev->isp_ctx.isp_hw_module;
> + struct isp_device *isp_dev = &p1_dev->isp_devs[module];
> + unsigned int reg_val;
> +
> + dev_dbg(dev, "- %s\n", __func__);
> +

We need to check runtime PM status here as well, because if the device was
suspended, there is nothing to do here.

> + enable_sys_clock(p1_dev);
> +
> + /* V4L2 stream-on phase & restore HW stream-on status */
> + if (p1_dev->cam_dev.streaming) {
> + dev_dbg(dev, "Cam:%d resume,enable VF\n", module);
> + /* Enable CMOS */
> + reg_val = readl(isp_dev->regs + REG_TG_SEN_MODE);
> + writel((reg_val | CMOS_EN_BIT),
> + isp_dev->regs + REG_TG_SEN_MODE);
> + /* Enable VF */
> + reg_val = readl(isp_dev->regs + REG_TG_VF_CON);
> + writel((reg_val | VFDATA_EN_BIT),
> + isp_dev->regs + REG_TG_VF_CON);
> + }

Does the hardware keep all the state, e.g. queued buffers, during suspend?
Would the code above continue all the capture from the next buffer, as
queued by the userspace before the suspend?

> +
> + return 0;
> +}
> +
> +static int mtk_isp_probe(struct platform_device *pdev)
> +{
> + struct isp_p1_device *p1_dev;
> + struct mtk_isp_p1_ctx *isp_ctx;
> + struct isp_device *isp_dev;
> + struct device *dev = &pdev->dev;
> + struct resource *res;
> + int irq;
> + int ret;
> + unsigned int i;
> +
> + p1_dev = devm_kzalloc(dev, sizeof(*p1_dev), GFP_KERNEL);
> + if (!p1_dev)
> + return -ENOMEM;
> +
> + dev_set_drvdata(dev, p1_dev);
> + isp_ctx = &p1_dev->isp_ctx;
> + p1_dev->pdev = pdev;

Perhaps you want to store &pdev->dev instead of pdev? I'm not sure a
reference to platform_device is very useful later in the code.

> +
> + for (i = ISP_CAMSYS_CONFIG_IDX; i < ISP_DEV_NODE_NUM; i++) {

I think we want to start from 0 here?

> + isp_dev = &p1_dev->isp_devs[i];
> + isp_dev->isp_hw_module = i;
> + isp_dev->dev = dev;

p1_dev already includes a pointer to this.

> + res = platform_get_resource(pdev, IORESOURCE_MEM, i);
> + isp_dev->regs = devm_ioremap_resource(dev, res);
> +
> + dev_dbg(dev, "cam%u, map_addr=0x%lx\n",
> + i, (unsigned long)isp_dev->regs);
> +
> + if (!isp_dev->regs)

devm_ioremap_resource() returns ERR_PTR() not NULL on error.

> + return PTR_ERR(isp_dev->regs);
> +
> + /* Support IRQ from ISP_CAM_A_IDX */
> + if (i >= ISP_CAM_A_IDX) {
> + /* Reg & interrupts index is shifted with 1 */

The reader can already see that it's shifted from the code below. The
comment should say _why_ it is shifted.

> + irq = platform_get_irq(pdev, i - 1);

The bindings have 3 IRQs, but we only seem to request 2 here. Is that
expected?

> + if (irq) {

Please invert this if, so that it bails out on error. Also, this should
check for negative errors codes, not 0.

> + ret = devm_request_irq(dev, irq,
> + isp_irq_cam,
> + IRQF_SHARED,
> + dev_driver_string(dev),

Use dev_name().

> + (void *)isp_dev);

No need to cast to void *.

> + if (ret) {
> + dev_err(dev,
> + "req_irq fail, dev:%s irq=%d\n",
> + dev->of_node->name,
> + irq);
> + return ret;
> + }
> + dev_dbg(dev, "Registered irq=%d, ISR:%s\n",
> + irq, dev_driver_string(dev));
> + }
> + }
> + spin_lock_init(&isp_dev->spinlock_irq);
> + }

We might want to move out the body of this loop to a separate function to
keep this function shorter.

> +
> + p1_dev->isp_ctx.num_clks = ARRAY_SIZE(mtk_isp_clks);
> + p1_dev->isp_ctx.clk_list =

nit: "list" is the term commonly used for the list data structure. There is
also a convention to call the length of array XXX num_XXX, so how about
clks and num_clks?

> + devm_kcalloc(dev,
> + p1_dev->isp_ctx.num_clks,
> + sizeof(*p1_dev->isp_ctx.clk_list),
> + GFP_KERNEL);
> + if (!p1_dev->isp_ctx.clk_list)
> + return -ENOMEM;
> +
> + for (i = 0; i < p1_dev->isp_ctx.num_clks; ++i)
> + p1_dev->isp_ctx.clk_list->id = mtk_isp_clks[i];

Shouldn't this be clk_list[i].id?

> +
> + ret = devm_clk_bulk_get(dev,
> + p1_dev->isp_ctx.num_clks,
> + p1_dev->isp_ctx.clk_list);
> + if (ret) {
> + dev_err(dev, "cannot get isp cam clock:%d\n", ret);
> + return ret;
> + }
> +
> + /* Initialize reserved DMA memory */
> + ret = mtk_cam_reserved_memory_init(p1_dev);
> + if (ret) {
> + dev_err(dev, "failed to configure DMA memory:%d\n", ret);
> + goto err_init;
> + }
> +
> + /* Initialize the v4l2 common part */
> + ret = mtk_cam_dev_init(pdev, &p1_dev->cam_dev);
> + if (ret)
> + goto err_init;
> +
> + spin_lock_init(&isp_ctx->p1_enqueue_list.lock);
> + pm_runtime_enable(dev);
> +
> + return 0;
> +
> +err_init:
> + if (p1_dev->cam_dev.smem_dev)
> + device_unregister(p1_dev->cam_dev.smem_dev);
> +
> + return ret;
> +}
> +
> +static int mtk_isp_remove(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct isp_p1_device *p1_dev = dev_get_drvdata(dev);
> +
> + pm_runtime_disable(dev);
> + mtk_cam_dev_release(pdev, &p1_dev->cam_dev);
> +
> + return 0;
> +}
> +
> +static const struct dev_pm_ops mtk_isp_pm_ops = {
> + SET_SYSTEM_SLEEP_PM_OPS(mtk_isp_suspend, mtk_isp_resume)
> + SET_RUNTIME_PM_OPS(mtk_isp_suspend, mtk_isp_resume, NULL)

For V4L2 drivers system and runtime PM ops would normally be completely
different. Runtime PM ops would be called when the hardware is idle already
or is about to become active. System PM ops would be called at system power
state change and the hardware might be both idle or active. Please also see
my comments to mtk_isp_suspend() and mtk_isp_resume() above.

> +};
> +
> +static struct platform_driver mtk_isp_driver = {
> + .probe = mtk_isp_probe,
> + .remove = mtk_isp_remove,
> + .driver = {
> + .name = "mtk-cam",

Shouldn't this be something like mtk-cam-p1? Please make sure this
reasonably consistent with other drivers.

> + .of_match_table = of_match_ptr(mtk_isp_of_ids),
> + .pm = &mtk_isp_pm_ops,
> + }
> +};
> +
> +module_platform_driver(mtk_isp_driver);
> +
> +MODULE_DESCRIPTION("Camera ISP driver");

Mediatek Camera P1 ISP driver? Please make sure this is reasonably
consistent with other drivers (SenInf, DIP, FD).

> +MODULE_LICENSE("GPL");

GPL v2

diff --git a/drivers/media/platform/mtk-isp/isp_50/cam/mtk_cam.h b/drivers/media/platform/mtk-isp/isp_50/cam/mtk_cam.h
new file mode 100644
index 000000000000..6af3f569664c
> --- /dev/null
> +++ b/drivers/media/platform/mtk-isp/isp_50/cam/mtk_cam.h
@@ -0,0 +1,243 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (c) 2018 MediaTek Inc.
> + */
> +
> +#ifndef __CAMERA_ISP_H
> +#define __CAMERA_ISP_H
> +
> +#include <linux/cdev.h>
> +#include <linux/clk.h>
> +#include <linux/interrupt.h>
> +#include <linux/ioctl.h>
> +#include <linux/irqreturn.h>
> +#include <linux/miscdevice.h>
> +#include <linux/pm_qos.h>
> +#include <linux/scatterlist.h>
> +
> +#include "mtk_cam-scp.h"
> +#include "mtk_cam-v4l2-util.h"
> +
> +#define CAM_A_MAX_WIDTH 3328
> +#define CAM_A_MAX_HEIGHT 2496
> +#define CAM_B_MAX_WIDTH 5376
> +#define CAM_B_MAX_HEIGHT 4032
> +
> +#define CAM_MIN_WIDTH 80
> +#define CAM_MIN_HEIGHT 60
> +
> +#define IMG_MAX_WIDTH CAM_B_MAX_WIDTH
> +#define IMG_MAX_HEIGHT CAM_B_MAX_HEIGHT
> +#define IMG_MIN_WIDTH CAM_MIN_WIDTH
> +#define IMG_MIN_HEIGHT CAM_MIN_HEIGHT
> +
> +#define RRZ_MAX_WIDTH CAM_B_MAX_WIDTH
> +#define RRZ_MAX_HEIGHT CAM_B_MAX_HEIGHT
> +#define RRZ_MIN_WIDTH CAM_MIN_WIDTH
> +#define RRZ_MIN_HEIGHT CAM_MIN_HEIGHT
> +
> +#define R_IMGO BIT(0)
> +#define R_RRZO BIT(1)
> +#define R_AAO BIT(3)
> +#define R_AFO BIT(4)
> +#define R_LCSO BIT(5)
> +#define R_PDO BIT(6)
> +#define R_LMVO BIT(7)
> +#define R_FLKO BIT(8)
> +#define R_RSSO BIT(9)
> +#define R_PSO BIT(10)
> +
> +#define CQ_BUFFER_COUNT 3
> +#define IRQ_DATA_BUF_SIZE 4
> +#define CQ_ADDRESS_OFFSET 0x640
> +
> +#define ISP_COMPOSING_MAX_NUM 4
> +#define ISP_FRAME_COMPOSING_MAX_NUM 3
> +
> +#define IRQ_STAT_STR "cam%c, SOF_%d irq(0x%x), " \
> + "dma(0x%x), frame_num(%d)/cq_num(%d), " \
> + "fbc1(0x%x), fbc2(0x%x)\n"
> +
> +/*
> + * In order with the sequence of device nodes defined in dtsi rule,
> + * one hardware module should be mapping to one node.
> + */
> +enum isp_dev_node_enum {
> + ISP_CAMSYS_CONFIG_IDX = 0,
> + ISP_CAM_UNI_IDX,
> + ISP_CAM_A_IDX,
> + ISP_CAM_B_IDX,
> + ISP_DEV_NODE_NUM
> +};
> +
> +/* Image RAW path for ISP P1 module. */
> +enum isp_raw_path_enum {
> + ISP_PROCESS_RAW_PATH = 0,
> + ISP_PURE_RAW_PATH
> +};
> +
> +/* State for struct mtk_isp_p1_ctx: composer_state */
> +enum {
> + SCP_ON = 0,
> + SCP_OFF
> +};

Hmm, looks like bool.

> +
> +enum {
> + IMG_FMT_UNKNOWN = 0x0000,
> + IMG_FMT_RAW_START = 0x2200,
> + IMG_FMT_BAYER8 = IMG_FMT_RAW_START,
> + IMG_FMT_BAYER10,
> + IMG_FMT_BAYER12,
> + IMG_FMT_BAYER14,
> + IMG_FMT_FG_BAYER8,
> + IMG_FMT_FG_BAYER10,
> + IMG_FMT_FG_BAYER12,
> + IMG_FMT_FG_BAYER14,
> +};
> +
> +enum {
> + RAW_PXL_ID_B = 0,
> + RAW_PXL_ID_GB,
> + RAW_PXL_ID_GR,
> + RAW_PXL_ID_R
> +};

Please use macros with explicitly assigned values for hardware/firmware ABI
definitions.

> +
> +struct isp_queue {
> + struct list_head queue;
> + atomic_t queue_cnt;
> + spinlock_t lock; /* queue attributes protection */
> +};
> +
> +struct isp_thread {
> + struct task_struct *thread;
> + wait_queue_head_t wq;
> +};
> +
> +struct mtk_isp_queue_work {
> + union {
> + struct mtk_isp_scp_p1_cmd cmd;
> + struct p1_frame_param frameparams;
> + };
> + struct list_head list_entry;
> + enum mtk_isp_scp_type type;
> +};
> +
> +struct mtk_cam_dev_stat_event_data {
> + __u32 frame_seq_no;
> + __u32 meta0_vb2_index;
> + __u32 meta1_vb2_index;
> + __u32 irq_status_mask;
> + __u32 dma_status_mask;
> +};
> +
> +struct mtk_isp_queue_job {
> + struct list_head list_entry;
> + struct list_head list_buf;
> + unsigned int request_fd;
> + unsigned int frame_seq_no;
> +};

Please document the structs above using kerneldoc.

> +
> +/*
> + * struct isp_device - the ISP device information
> + *
> + * @dev: Pointer to struct device
> + * @regs: Camera ISP base register address
> + * @spinlock_irq: Used to protect register read/write data
> + * @current_frame: Current frame sequence number, set when SOF
> + * @meta0_vb2_index: Meta0 vb2 buffer index, set when SOF
> + * @meta1_vb2_index: Meta1 vb2 buffer index, set when SOF
> + * @sof_count: The accumulated SOF counter
> + * @isp_hw_module: Identity camera A or B
> + *
> + */
> +struct isp_device {

mtk_isp_device?

> + struct device *dev;
> + void __iomem *regs;
> + spinlock_t spinlock_irq; /* ISP reg setting integrity */
> + unsigned int current_frame;
> + unsigned int meta0_vb2_index;
> + unsigned int meta1_vb2_index;
> + u8 sof_count;
> + u8 isp_hw_module;
> +};
> +
> +/*
> + * struct mtk_isp_p1_ctx - the ISP device information
> + *
> + * @composer_txlist: Queue for SCP TX data including SCP_ISP_CMD & SCP_ISP_FRAME
> + * @composer_tx_thread: TX Thread for SCP data tranmission
> + * @cmd_queued: The number of SCP_ISP_CMD commands will be sent
> + * @ipi_occupied: The total number of SCP TX data has beent sent
> + * @scp_state: The state of SCP control
> + * @composing_frame: The total number of SCP_ISP_FRAME has beent sent
> + * @composed_frame_id: The ack. frame sequence by SCP
> + * @composer_deinit_thread: The de-initialized thread
> + * @p1_enqueue_list: Queue for ISP frame buffers
> + * @isp_deque_thread: Thread for handling ISP frame buffers dequeue
> + * @irq_event_datas: Ring buffer for struct mtk_cam_dev_stat_event_data data
> + * @irq_data_start: Start index of irq_event_datas ring buffer
> + * @irq_data_end: End index of irq_event_datas ring buffer
> + * @irq_dequeue_lock: Lock to protect irq_event_datas ring buffer
> + * @scp_mem_pa: DMA address for SCP device
> + * @scp_mem_iova: DMA address for ISP HW DMA devices
> + * @frame_seq_no: Sequence number for ISP frame buffer
> + * @isp_hw_module: Active camera HW module
> + * @num_clks: The number of driver's clock
> + * @clk_list: The list of clock data
> + * @lock: Lock to protect context operations
> + *
> + */
> +struct mtk_isp_p1_ctx {
> + struct isp_queue composer_txlist;
> + struct isp_thread composer_tx_thread;
> + atomic_t cmd_queued;
> + atomic_t ipi_occupied;
> + atomic_t scp_state;
> + atomic_t composing_frame;
> + atomic_t composed_frame_id;
> + struct isp_thread composer_deinit_thread;
> + struct isp_queue p1_enqueue_list;
> + struct isp_thread isp_deque_thread;
> + struct mtk_cam_dev_stat_event_data irq_event_datas[IRQ_DATA_BUF_SIZE];
> + atomic_t irq_data_start;
> + atomic_t irq_data_end;
> + spinlock_t irq_dequeue_lock; /* ISP frame dequeuq protection */

Already documented in kerneldoc.

> + dma_addr_t scp_mem_pa;
> + dma_addr_t scp_mem_iova;
> + int frame_seq_no;
> + unsigned int isp_hw_module;
> + unsigned int isp_raw_path;

Not documented above.

> + unsigned int num_clks;
> + struct clk_bulk_data *clk_list;
> + struct mutex lock; /* Protect context operations */

Already documented in kerneldoc.

> +};
> +
> +struct isp_p1_device {
> + struct platform_device *pdev;
> + struct platform_device *scp_pdev;
> + struct rproc *rproc_handle;
> + struct mtk_isp_p1_ctx isp_ctx;
> + struct mtk_cam_dev cam_dev;
> + struct isp_device isp_devs[ISP_DEV_NODE_NUM];
> +};

Please document in a kerneldoc comment.

> +
> +static inline struct isp_p1_device *
> +p1_ctx_to_dev(const struct mtk_isp_p1_ctx *__p1_ctx)
> +{
> + return container_of(__p1_ctx, struct isp_p1_device, isp_ctx);
> +}
> +
> +static inline struct isp_p1_device *get_p1_device(struct device *dev)
> +{
> + return ((struct isp_p1_device *)dev_get_drvdata(dev));

No need to cast. And, I don't think we need a function for this, just call
dev_get_drvdata() directly.

Best regards,
Tomasz