// SPDX-License-Identifier: GPL-2.0-or-later
/*
* TW5864 driver - core functions
*
* Copyright (C) 2016 Bluecherry, LLC <[email protected]>
*/
#include <linux/init.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/kmod.h>
#include <linux/sound.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/pm.h>
#include <linux/pci_ids.h>
#include <linux/jiffies.h>
#include <asm/dma.h>
#include <media/v4l2-dev.h>
#include "tw5864.h"
#include "tw5864-reg.h"
MODULE_DESCRIPTION("V4L2 driver module for tw5864-based multimedia capture & encoding devices");
MODULE_AUTHOR("Bluecherry Maintainers <[email protected]>");
MODULE_AUTHOR("Andrey Utkin <[email protected]>");
MODULE_LICENSE("GPL");
/*
* BEWARE OF KNOWN ISSUES WITH VIDEO QUALITY
*
* This driver was developed by Bluecherry LLC by deducing behaviour of
* original manufacturer's driver, from both source code and execution traces.
* It is known that there are some artifacts on output video with this driver:
* - on all known hardware samples: random pixels of wrong color (mostly
* white, red or blue) appearing and disappearing on sequences of P-frames;
* - on some hardware samples (known with H.264 core version e006:2800):
* total madness on P-frames: blocks of wrong luminance; blocks of wrong
* colors "creeping" across the picture.
* There is a workaround for both issues: avoid P-frames by setting GOP size
* to 1. To do that, run this command on device files created by this driver:
*
* v4l2-ctl --device /dev/videoX --set-ctrl=video_gop_size=1
*
* These issues are not decoding errors; all produced H.264 streams are decoded
* properly. Streams without P-frames don't have these artifacts so it's not
* analog-to-digital conversion issues nor internal memory errors; we conclude
* it's internal H.264 encoder issues.
* We cannot even check the original driver's behaviour because it has never
* worked properly at all in our development environment. So these issues may
* be actually related to firmware or hardware. However it may be that there's
* just some more register settings missing in the driver which would please
* the hardware.
* Manufacturer didn't help much on our inquiries, but feel free to disturb
* again the support of Intersil (owner of former Techwell).
*/
/* take first free /dev/videoX indexes by default */
static unsigned int video_nr[] = {[0 ... (TW5864_INPUTS - 1)] = -1 };
module_param_array(video_nr, int, NULL, 0444);
MODULE_PARM_DESC(video_nr, "video devices numbers array");
/*
* Please add any new PCI IDs to: https://pci-ids.ucw.cz. This keeps
* the PCI ID database up to date. Note that the entries must be
* added under vendor 0x1797 (Techwell Inc.) as subsystem IDs.
*/
static const struct pci_device_id tw5864_pci_tbl[] = {
{PCI_DEVICE(PCI_VENDOR_ID_TECHWELL, PCI_DEVICE_ID_TECHWELL_5864)},
{0,}
};
void tw5864_irqmask_apply(struct tw5864_dev *dev)
{
tw_writel(TW5864_INTR_ENABLE_L, dev->irqmask & 0xffff);
tw_writel(TW5864_INTR_ENABLE_H, (dev->irqmask >> 16));
}
static void tw5864_interrupts_disable(struct tw5864_dev *dev)
{
unsigned long flags;
spin_lock_irqsave(&dev->slock, flags);
dev->irqmask = 0;
tw5864_irqmask_apply(dev);
spin_unlock_irqrestore(&dev->slock, flags);
}
static void tw5864_timer_isr(struct tw5864_dev *dev);
static void tw5864_h264_isr(struct tw5864_dev *dev);
static irqreturn_t tw5864_isr(int irq, void *dev_id)
{
struct tw5864_dev *dev = dev_id;
u32 status;
status = tw_readl(TW5864_INTR_STATUS_L) |
tw_readl(TW5864_INTR_STATUS_H) << 16;
if (!status)
return IRQ_NONE;
tw_writel(TW5864_INTR_CLR_L, 0xffff);
tw_writel(TW5864_INTR_CLR_H, 0xffff);
if (status & TW5864_INTR_VLC_DONE)
tw5864_h264_isr(dev);
if (status & TW5864_INTR_TIMER)
tw5864_timer_isr(dev);
if (!(status & (TW5864_INTR_TIMER | TW5864_INTR_VLC_DONE))) {
dev_dbg(&dev->pci->dev, "Unknown interrupt, status 0x%08X\n",
status);
}
return IRQ_HANDLED;
}
static void tw5864_h264_isr(struct tw5864_dev *dev)
{
int channel = tw_readl(TW5864_DSP) & TW5864_DSP_ENC_CHN;
struct tw5864_input *input = &dev->inputs[channel];
int cur_frame_index, next_frame_index;
struct tw5864_h264_frame *cur_frame, *next_frame;
unsigned long flags;
spin_lock_irqsave(&dev->slock, flags);
cur_frame_index = dev->h264_buf_w_index;
next_frame_index = (cur_frame_index + 1) % H264_BUF_CNT;
cur_frame = &dev->h264_buf[cur_frame_index];
next_frame = &dev->h264_buf[next_frame_index];
if (next_frame_index != dev->h264_buf_r_index) {
cur_frame->vlc_len = tw_readl(TW5864_VLC_LENGTH) << 2;
cur_frame->checksum = tw_readl(TW5864_VLC_CRC_REG);
cur_frame->input = input;
cur_frame->timestamp = ktime_get_ns();
cur_frame->seqno = input->frame_seqno;
cur_frame->gop_seqno = input->frame_gop_seqno;
dev->h264_buf_w_index = next_frame_index;
queue_work(system_bh_wq, &dev->bh_work);
cur_frame = next_frame;
spin_lock(&input->slock);
input->frame_seqno++;
input->frame_gop_seqno++;
if (input->frame_gop_seqno >= input->gop)
input->frame_gop_seqno = 0;
spin_unlock(&input->slock);
} else {
dev_err(&dev->pci->dev,
"Skipped frame on input %d because all buffers busy\n",
channel);
}
dev->encoder_busy = 0;
spin_unlock_irqrestore(&dev->slock, flags);
tw_writel(TW5864_VLC_STREAM_BASE_ADDR, cur_frame->vlc.dma_addr);
tw_writel(TW5864_MV_STREAM_BASE_ADDR, cur_frame->mv.dma_addr);
/* Additional ack for this interrupt */
tw_writel(TW5864_VLC_DSP_INTR, 0x00000001);
tw_writel(TW5864_PCI_INTR_STATUS, TW5864_VLC_DONE_INTR);
}
static void tw5864_input_deadline_update(struct tw5864_input *input)
{
input->new_frame_deadline = jiffies + msecs_to_jiffies(1000);
}
static void tw5864_timer_isr(struct tw5864_dev *dev)
{
unsigned long flags;
int i;
int encoder_busy;
/* Additional ack for this interrupt */
tw_writel(TW5864_PCI_INTR_STATUS, TW5864_TIMER_INTR);
spin_lock_irqsave(&dev->slock, flags);
encoder_busy = dev->encoder_busy;
spin_unlock_irqrestore(&dev->slock, flags);
if (encoder_busy)
return;
/*
* Traversing inputs in round-robin fashion, starting from next to the
* last processed one
*/
for (i = 0; i < TW5864_INPUTS; i++) {
int next_input = (i + dev->next_input) % TW5864_INPUTS;
struct tw5864_input *input = &dev->inputs[next_input];
int raw_buf_id; /* id of internal buf with last raw frame */
spin_lock_irqsave(&input->slock, flags);
if (!input->enabled)
goto next;
/* Check if new raw frame is available */
raw_buf_id = tw_mask_shift_readl(TW5864_SENIF_ORG_FRM_PTR1, 0x3,
2 * input->nr);
if (input->buf_id != raw_buf_id) {
input->buf_id = raw_buf_id;
tw5864_input_deadline_update(input);
spin_unlock_irqrestore(&input->slock, flags);
spin_lock_irqsave(&dev->slock, flags);
dev->encoder_busy = 1;
dev->next_input = (next_input + 1) % TW5864_INPUTS;
spin_unlock_irqrestore(&dev->slock, flags);
tw5864_request_encoded_frame(input);
break;
}
/* No new raw frame; check if channel is stuck */
if (time_is_after_jiffies(input->new_frame_deadline)) {
/* If stuck, request new raw frames again */
tw_mask_shift_writel(TW5864_ENC_BUF_PTR_REC1, 0x3,
2 * input->nr, input->buf_id + 3);
tw5864_input_deadline_update(input);
}
next:
spin_unlock_irqrestore(&input->slock, flags);
}
}
static int tw5864_initdev(struct pci_dev *pci_dev,
const struct pci_device_id *pci_id)
{
struct tw5864_dev *dev;
int err;
dev = devm_kzalloc(&pci_dev->dev, sizeof(*dev), GFP_KERNEL);
if (!dev)
return -ENOMEM;
snprintf(dev->name, sizeof(dev->name), "tw5864:%s", pci_name(pci_dev));
err = v4l2_device_register(&pci_dev->dev, &dev->v4l2_dev);
if (err)
return err;
/* pci init */
dev->pci = pci_dev;
err = pcim_enable_device(pci_dev);
if (err) {
dev_err(&dev->pci->dev, "pcim_enable_device() failed\n");
goto unreg_v4l2;
}
pci_set_master(pci_dev);
err = dma_set_mask(&pci_dev->dev, DMA_BIT_MASK(32));
if (err) {
dev_err(&dev->pci->dev, "32 bit PCI DMA is not supported\n");
goto unreg_v4l2;
}
/* get mmio */
err = pcim_iomap_regions(pci_dev, BIT(0), dev->name);
if (err) {
dev_err(&dev->pci->dev, "Cannot request regions for MMIO\n");
goto unreg_v4l2;
}
dev->mmio = pcim_iomap_table(pci_dev)[0];
spin_lock_init(&dev->slock);
dev_info(&pci_dev->dev, "TW5864 hardware version: %04x\n",
tw_readl(TW5864_HW_VERSION));
dev_info(&pci_dev->dev, "TW5864 H.264 core version: %04x:%04x\n",
tw_readl(TW5864_H264REV),
tw_readl(TW5864_UNDECLARED_H264REV_PART2));
err = tw5864_video_init(dev, video_nr);
if (err)
goto unreg_v4l2;
/* get irq */
err = devm_request_irq(&pci_dev->dev, pci_dev->irq, tw5864_isr,
IRQF_SHARED, "tw5864", dev);
if (err < 0) {
dev_err(&dev->pci->dev, "can't get IRQ %d\n", pci_dev->irq);
goto fini_video;
}
dev_info(&pci_dev->dev, "Note: there are known video quality issues. For details\n");
dev_info(&pci_dev->dev, "see the comment in drivers/media/pci/tw5864/tw5864-core.c.\n");
return 0;
fini_video:
tw5864_video_fini(dev);
unreg_v4l2:
v4l2_device_unregister(&dev->v4l2_dev);
return err;
}
static void tw5864_finidev(struct pci_dev *pci_dev)
{
struct v4l2_device *v4l2_dev = pci_get_drvdata(pci_dev);
struct tw5864_dev *dev =
container_of(v4l2_dev, struct tw5864_dev, v4l2_dev);
/* shutdown subsystems */
tw5864_interrupts_disable(dev);
/* unregister */
tw5864_video_fini(dev);
v4l2_device_unregister(&dev->v4l2_dev);
}
static struct pci_driver tw5864_pci_driver = {
.name = "tw5864",
.id_table = tw5864_pci_tbl,
.probe = tw5864_initdev,
.remove = tw5864_finidev,
};
module_pci_driver(tw5864_pci_driver);
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