// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright (C) 2019 BayLibre, SAS
 * Author: Maxime Jourdan <mjourdan@baylibre.com>
 */

#include <media/v4l2-mem2mem.h>
#include <media/videobuf2-dma-contig.h>

#include "vdec_helpers.h"
#include "dos_regs.h"
#include "codec_h264.h"

#define SIZE_EXT_FW	(20 * SZ_1K)
#define SIZE_WORKSPACE	0x1ee000
#define SIZE_SEI	(8 * SZ_1K)

/*
 * Offset added by the firmware which must be substracted
 * from the workspace phyaddr
 */
#define WORKSPACE_BUF_OFFSET	0x1000000

/* ISR status */
#define CMD_MASK		GENMASK(7, 0)
#define CMD_SRC_CHANGE		1
#define CMD_FRAMES_READY	2
#define CMD_FATAL_ERROR		6
#define CMD_BAD_WIDTH		7
#define CMD_BAD_HEIGHT		8

#define SEI_DATA_READY	BIT(15)

/* Picture type */
#define PIC_TOP_BOT	5
#define PIC_BOT_TOP	6

/* Size of Motion Vector per macroblock */
#define MB_MV_SIZE	96

/* Frame status data */
#define PIC_STRUCT_BIT	5
#define PIC_STRUCT_MASK	GENMASK(2, 0)
#define BUF_IDX_MASK	GENMASK(4, 0)
#define ERROR_FLAG	BIT(9)
#define OFFSET_BIT	16
#define OFFSET_MASK	GENMASK(15, 0)

/* Bitstream parsed data */
#define MB_TOTAL_BIT	8
#define MB_TOTAL_MASK	GENMASK(15, 0)
#define MB_WIDTH_MASK	GENMASK(7, 0)
#define MAX_REF_BIT	24
#define MAX_REF_MASK	GENMASK(6, 0)
#define AR_IDC_BIT	16
#define AR_IDC_MASK	GENMASK(7, 0)
#define AR_PRESENT_FLAG	BIT(0)
#define AR_EXTEND	0xff

/*
 * Buffer to send to the ESPARSER to signal End Of Stream for H.264.
 * This is a 16x16 encoded picture that will trigger drain firmware-side.
 * There is no known alternative.
 */
static const u8 eos_sequence[SZ_4K] = {
	0x00, 0x00, 0x00, 0x01, 0x06, 0x05, 0xff, 0xe4, 0xdc, 0x45, 0xe9, 0xbd,
	0xe6, 0xd9, 0x48, 0xb7,	0x96, 0x2c, 0xd8, 0x20, 0xd9, 0x23, 0xee, 0xef,
	0x78, 0x32, 0x36, 0x34, 0x20, 0x2d, 0x20, 0x63,	0x6f, 0x72, 0x65, 0x20,
	0x36, 0x37, 0x20, 0x72, 0x31, 0x31, 0x33, 0x30, 0x20, 0x38, 0x34, 0x37,
	0x35, 0x39, 0x37, 0x37, 0x20, 0x2d, 0x20, 0x48, 0x2e, 0x32, 0x36, 0x34,
	0x2f, 0x4d, 0x50, 0x45,	0x47, 0x2d, 0x34, 0x20, 0x41, 0x56, 0x43, 0x20,
	0x63, 0x6f, 0x64, 0x65, 0x63, 0x20, 0x2d, 0x20,	0x43, 0x6f, 0x70, 0x79,
	0x6c, 0x65, 0x66, 0x74, 0x20, 0x32, 0x30, 0x30, 0x33, 0x2d, 0x32, 0x30,
	0x30, 0x39, 0x20, 0x2d, 0x20, 0x68, 0x74, 0x74, 0x70, 0x3a, 0x2f, 0x2f,
	0x77, 0x77, 0x77, 0x2e,	0x76, 0x69, 0x64, 0x65, 0x6f, 0x6c, 0x61, 0x6e,
	0x2e, 0x6f, 0x72, 0x67, 0x2f, 0x78, 0x32, 0x36,	0x34, 0x2e, 0x68, 0x74,
	0x6d, 0x6c, 0x20, 0x2d, 0x20, 0x6f, 0x70, 0x74, 0x69, 0x6f, 0x6e, 0x73,
	0x3a, 0x20, 0x63, 0x61, 0x62, 0x61, 0x63, 0x3d, 0x31, 0x20, 0x72, 0x65,
	0x66, 0x3d, 0x31, 0x20,	0x64, 0x65, 0x62, 0x6c, 0x6f, 0x63, 0x6b, 0x3d,
	0x31, 0x3a, 0x30, 0x3a, 0x30, 0x20, 0x61, 0x6e,	0x61, 0x6c, 0x79, 0x73,
	0x65, 0x3d, 0x30, 0x78, 0x31, 0x3a, 0x30, 0x78, 0x31, 0x31, 0x31, 0x20,
	0x6d, 0x65, 0x3d, 0x68, 0x65, 0x78, 0x20, 0x73, 0x75, 0x62, 0x6d, 0x65,
	0x3d, 0x36, 0x20, 0x70,	0x73, 0x79, 0x5f, 0x72, 0x64, 0x3d, 0x31, 0x2e,
	0x30, 0x3a, 0x30, 0x2e, 0x30, 0x20, 0x6d, 0x69,	0x78, 0x65, 0x64, 0x5f,
	0x72, 0x65, 0x66, 0x3d, 0x30, 0x20, 0x6d, 0x65, 0x5f, 0x72, 0x61, 0x6e,
	0x67, 0x65, 0x3d, 0x31, 0x36, 0x20, 0x63, 0x68, 0x72, 0x6f, 0x6d, 0x61,
	0x5f, 0x6d, 0x65, 0x3d,	0x31, 0x20, 0x74, 0x72, 0x65, 0x6c, 0x6c, 0x69,
	0x73, 0x3d, 0x30, 0x20, 0x38, 0x78, 0x38, 0x64,	0x63, 0x74, 0x3d, 0x30,
	0x20, 0x63, 0x71, 0x6d, 0x3d, 0x30, 0x20, 0x64, 0x65, 0x61, 0x64, 0x7a,
	0x6f, 0x6e, 0x65, 0x3d, 0x32, 0x31, 0x2c, 0x31, 0x31, 0x20, 0x63, 0x68,
	0x72, 0x6f, 0x6d, 0x61,	0x5f, 0x71, 0x70, 0x5f, 0x6f, 0x66, 0x66, 0x73,
	0x65, 0x74, 0x3d, 0x2d, 0x32, 0x20, 0x74, 0x68,	0x72, 0x65, 0x61, 0x64,
	0x73, 0x3d, 0x31, 0x20, 0x6e, 0x72, 0x3d, 0x30, 0x20, 0x64, 0x65, 0x63,
	0x69, 0x6d, 0x61, 0x74, 0x65, 0x3d, 0x31, 0x20, 0x6d, 0x62, 0x61, 0x66,
	0x66, 0x3d, 0x30, 0x20,	0x62, 0x66, 0x72, 0x61, 0x6d, 0x65, 0x73, 0x3d,
	0x30, 0x20, 0x6b, 0x65, 0x79, 0x69, 0x6e, 0x74,	0x3d, 0x32, 0x35, 0x30,
	0x20, 0x6b, 0x65, 0x79, 0x69, 0x6e, 0x74, 0x5f, 0x6d, 0x69, 0x6e, 0x3d,
	0x32, 0x35, 0x20, 0x73, 0x63, 0x65, 0x6e, 0x65, 0x63, 0x75, 0x74, 0x3d,
	0x34, 0x30, 0x20, 0x72,	0x63, 0x3d, 0x61, 0x62, 0x72, 0x20, 0x62, 0x69,
	0x74, 0x72, 0x61, 0x74, 0x65, 0x3d, 0x31, 0x30,	0x20, 0x72, 0x61, 0x74,
	0x65, 0x74, 0x6f, 0x6c, 0x3d, 0x31, 0x2e, 0x30, 0x20, 0x71, 0x63, 0x6f,
	0x6d, 0x70, 0x3d, 0x30, 0x2e, 0x36, 0x30, 0x20, 0x71, 0x70, 0x6d, 0x69,
	0x6e, 0x3d, 0x31, 0x30,	0x20, 0x71, 0x70, 0x6d, 0x61, 0x78, 0x3d, 0x35,
	0x31, 0x20, 0x71, 0x70, 0x73, 0x74, 0x65, 0x70,	0x3d, 0x34, 0x20, 0x69,
	0x70, 0x5f, 0x72, 0x61, 0x74, 0x69, 0x6f, 0x3d, 0x31, 0x2e, 0x34, 0x30,
	0x20, 0x61, 0x71, 0x3d, 0x31, 0x3a, 0x31, 0x2e, 0x30, 0x30, 0x00, 0x80,
	0x00, 0x00, 0x00, 0x01,	0x67, 0x4d, 0x40, 0x0a, 0x9a, 0x74, 0xf4, 0x20,
	0x00, 0x00, 0x03, 0x00, 0x20, 0x00, 0x00, 0x06,	0x51, 0xe2, 0x44, 0xd4,
	0x00, 0x00, 0x00, 0x01, 0x68, 0xee, 0x32, 0xc8, 0x00, 0x00, 0x00, 0x01,
	0x65, 0x88, 0x80, 0x20, 0x00, 0x08, 0x7f, 0xea, 0x6a, 0xe2, 0x99, 0xb6,
	0x57, 0xae, 0x49, 0x30,	0xf5, 0xfe, 0x5e, 0x46, 0x0b, 0x72, 0x44, 0xc4,
	0xe1, 0xfc, 0x62, 0xda, 0xf1, 0xfb, 0xa2, 0xdb,	0xd6, 0xbe, 0x5c, 0xd7,
	0x24, 0xa3, 0xf5, 0xb9, 0x2f, 0x57, 0x16, 0x49, 0x75, 0x47, 0x77, 0x09,
	0x5c, 0xa1, 0xb4, 0xc3, 0x4f, 0x60, 0x2b, 0xb0, 0x0c, 0xc8, 0xd6, 0x66,
	0xba, 0x9b, 0x82, 0x29,	0x33, 0x92, 0x26, 0x99, 0x31, 0x1c, 0x7f, 0x9b,
	0x00, 0x00, 0x01, 0x0ff,
};

static const u8 *codec_h264_eos_sequence(u32 *len)
{
	*len = ARRAY_SIZE(eos_sequence);
	return eos_sequence;
}

struct codec_h264 {
	/* H.264 decoder requires an extended firmware */
	void      *ext_fw_vaddr;
	dma_addr_t ext_fw_paddr;

	/* Buffer for the H.264 Workspace */
	void      *workspace_vaddr;
	dma_addr_t workspace_paddr;

	/* Buffer for the H.264 references MV */
	void      *ref_vaddr;
	dma_addr_t ref_paddr;
	u32	   ref_size;

	/* Buffer for parsed SEI data */
	void      *sei_vaddr;
	dma_addr_t sei_paddr;

	u32 mb_width;
	u32 mb_height;
	u32 max_refs;
};

static int codec_h264_can_recycle(struct amvdec_core *core)
{
	return !amvdec_read_dos(core, AV_SCRATCH_7) ||
	       !amvdec_read_dos(core, AV_SCRATCH_8);
}

static void codec_h264_recycle(struct amvdec_core *core, u32 buf_idx)
{
	/*
	 * Tell the firmware it can recycle this buffer.
	 * AV_SCRATCH_8 serves the same purpose.
	 */
	if (!amvdec_read_dos(core, AV_SCRATCH_7))
		amvdec_write_dos(core, AV_SCRATCH_7, buf_idx + 1);
	else
		amvdec_write_dos(core, AV_SCRATCH_8, buf_idx + 1);
}

static int codec_h264_start(struct amvdec_session *sess)
{
	u32 workspace_offset;
	struct amvdec_core *core = sess->core;
	struct codec_h264 *h264 = sess->priv;

	/* Allocate some memory for the H.264 decoder's state */
	h264->workspace_vaddr =
		dma_alloc_coherent(core->dev, SIZE_WORKSPACE,
				   &h264->workspace_paddr, GFP_KERNEL);
	if (!h264->workspace_vaddr)
		return -ENOMEM;

	/* Allocate some memory for the H.264 SEI dump */
	h264->sei_vaddr = dma_alloc_coherent(core->dev, SIZE_SEI,
					     &h264->sei_paddr, GFP_KERNEL);
	if (!h264->sei_vaddr)
		return -ENOMEM;

	amvdec_write_dos_bits(core, POWER_CTL_VLD, BIT(9) | BIT(6));

	workspace_offset = h264->workspace_paddr - WORKSPACE_BUF_OFFSET;
	amvdec_write_dos(core, AV_SCRATCH_1, workspace_offset);
	amvdec_write_dos(core, AV_SCRATCH_G, h264->ext_fw_paddr);
	amvdec_write_dos(core, AV_SCRATCH_I, h264->sei_paddr -
					     workspace_offset);

	/* Enable "error correction" */
	amvdec_write_dos(core, AV_SCRATCH_F,
			 (amvdec_read_dos(core, AV_SCRATCH_F) & 0xffffffc3) |
			 BIT(4) | BIT(7));

	amvdec_write_dos(core, MDEC_PIC_DC_THRESH, 0x404038aa);

	return 0;
}

static int codec_h264_stop(struct amvdec_session *sess)
{
	struct codec_h264 *h264 = sess->priv;
	struct amvdec_core *core = sess->core;

	if (h264->ext_fw_vaddr)
		dma_free_coherent(core->dev, SIZE_EXT_FW,
				  h264->ext_fw_vaddr, h264->ext_fw_paddr);

	if (h264->workspace_vaddr)
		dma_free_coherent(core->dev, SIZE_WORKSPACE,
				  h264->workspace_vaddr, h264->workspace_paddr);

	if (h264->ref_vaddr)
		dma_free_coherent(core->dev, h264->ref_size,
				  h264->ref_vaddr, h264->ref_paddr);

	if (h264->sei_vaddr)
		dma_free_coherent(core->dev, SIZE_SEI,
				  h264->sei_vaddr, h264->sei_paddr);

	return 0;
}

static int codec_h264_load_extended_firmware(struct amvdec_session *sess,
					     const u8 *data, u32 len)
{
	struct codec_h264 *h264;
	struct amvdec_core *core = sess->core;

	if (len < SIZE_EXT_FW)
		return -EINVAL;

	h264 = kzalloc(sizeof(*h264), GFP_KERNEL);
	if (!h264)
		return -ENOMEM;

	h264->ext_fw_vaddr = dma_alloc_coherent(core->dev, SIZE_EXT_FW,
						&h264->ext_fw_paddr,
						GFP_KERNEL);
	if (!h264->ext_fw_vaddr) {
		kfree(h264);
		return -ENOMEM;
	}

	memcpy(h264->ext_fw_vaddr, data, SIZE_EXT_FW);
	sess->priv = h264;

	return 0;
}

static const struct v4l2_fract par_table[] = {
	{ 1, 1 },   { 1, 1 },    { 12, 11 }, { 10, 11 },
	{ 16, 11 }, { 40, 33 },  { 24, 11 }, { 20, 11 },
	{ 32, 11 }, { 80, 33 },  { 18, 11 }, { 15, 11 },
	{ 64, 33 }, { 160, 99 }, { 4, 3 },   { 3, 2 },
	{ 2, 1 }
};

static void codec_h264_set_par(struct amvdec_session *sess)
{
	struct amvdec_core *core = sess->core;
	u32 seq_info = amvdec_read_dos(core, AV_SCRATCH_2);
	u32 ar_idc = (seq_info >> AR_IDC_BIT) & AR_IDC_MASK;

	if (!(seq_info & AR_PRESENT_FLAG))
		return;

	if (ar_idc == AR_EXTEND) {
		u32 ar_info = amvdec_read_dos(core, AV_SCRATCH_3);

		sess->pixelaspect.numerator = ar_info & 0xffff;
		sess->pixelaspect.denominator = (ar_info >> 16) & 0xffff;
		return;
	}

	if (ar_idc >= ARRAY_SIZE(par_table))
		return;

	sess->pixelaspect = par_table[ar_idc];
}

static void codec_h264_resume(struct amvdec_session *sess)
{
	struct amvdec_core *core = sess->core;
	struct codec_h264 *h264 = sess->priv;
	u32 mb_width, mb_height, mb_total;

	amvdec_set_canvases(sess,
			    (u32[]){ ANC0_CANVAS_ADDR, 0 },
			    (u32[]){ 24, 0 });

	dev_dbg(core->dev, "max_refs = %u; actual_dpb_size = %u\n",
		h264->max_refs, sess->num_dst_bufs);

	/* Align to a multiple of 4 macroblocks */
	mb_width = ALIGN(h264->mb_width, 4);
	mb_height = ALIGN(h264->mb_height, 4);
	mb_total = mb_width * mb_height;

	h264->ref_size = mb_total * MB_MV_SIZE * h264->max_refs;
	h264->ref_vaddr = dma_alloc_coherent(core->dev, h264->ref_size,
					     &h264->ref_paddr, GFP_KERNEL);
	if (!h264->ref_vaddr) {
		amvdec_abort(sess);
		return;
	}

	/* Address to store the references' MVs */
	amvdec_write_dos(core, AV_SCRATCH_1, h264->ref_paddr);
	/* End of ref MV */
	amvdec_write_dos(core, AV_SCRATCH_4, h264->ref_paddr + h264->ref_size);

	amvdec_write_dos(core, AV_SCRATCH_0, (h264->max_refs << 24) |
					     (sess->num_dst_bufs << 16) |
					     ((h264->max_refs - 1) << 8));
}

/*
 * Configure the H.264 decoder when the parser detected a parameter set change
 */
static void codec_h264_src_change(struct amvdec_session *sess)
{
	struct amvdec_core *core = sess->core;
	struct codec_h264 *h264 = sess->priv;
	u32 parsed_info, mb_total;
	u32 crop_infor, crop_bottom, crop_right;
	u32 frame_width, frame_height;

	sess->keyframe_found = 1;

	parsed_info = amvdec_read_dos(core, AV_SCRATCH_1);

	/* Total number of 16x16 macroblocks */
	mb_total = (parsed_info >> MB_TOTAL_BIT) & MB_TOTAL_MASK;
	/* Number of macroblocks per line */
	h264->mb_width = parsed_info & MB_WIDTH_MASK;
	/* Number of macroblock lines */
	h264->mb_height = mb_total / h264->mb_width;

	h264->max_refs = ((parsed_info >> MAX_REF_BIT) & MAX_REF_MASK) + 1;

	crop_infor = amvdec_read_dos(core, AV_SCRATCH_6);
	crop_bottom = (crop_infor & 0xff);
	crop_right = (crop_infor >> 16) & 0xff;

	frame_width = h264->mb_width * 16 - crop_right;
	frame_height = h264->mb_height * 16 - crop_bottom;

	dev_dbg(core->dev, "frame: %ux%u; crop: %u %u\n",
		frame_width, frame_height, crop_right, crop_bottom);

	codec_h264_set_par(sess);
	amvdec_src_change(sess, frame_width, frame_height, h264->max_refs + 5);
}

/*
 * The bitstream offset is split in half in 2 different registers.
 * Fetch its MSB here, which location depends on the frame number.
 */
static u32 get_offset_msb(struct amvdec_core *core, int frame_num)
{
	int take_msb = frame_num % 2;
	int reg_offset = (frame_num / 2) * 4;
	u32 offset_msb = amvdec_read_dos(core, AV_SCRATCH_A + reg_offset);

	if (take_msb)
		return offset_msb & 0xffff0000;

	return (offset_msb & 0x0000ffff) << 16;
}

static void codec_h264_frames_ready(struct amvdec_session *sess, u32 status)
{
	struct amvdec_core *core = sess->core;
	int error_count;
	int num_frames;
	int i;

	error_count = amvdec_read_dos(core, AV_SCRATCH_D);
	num_frames = (status >> 8) & 0xff;
	if (error_count) {
		dev_warn(core->dev,
			 "decoder error(s) happened, count %d\n", error_count);
		amvdec_write_dos(core, AV_SCRATCH_D, 0);
	}

	for (i = 0; i < num_frames; i++) {
		u32 frame_status = amvdec_read_dos(core, AV_SCRATCH_1 + i * 4);
		u32 buffer_index = frame_status & BUF_IDX_MASK;
		u32 pic_struct = (frame_status >> PIC_STRUCT_BIT) &
				 PIC_STRUCT_MASK;
		u32 offset = (frame_status >> OFFSET_BIT) & OFFSET_MASK;
		u32 field = V4L2_FIELD_NONE;

		/*
		 * A buffer decode error means it was decoded,
		 * but part of the picture will have artifacts.
		 * Typical reason is a temporarily corrupted bitstream
		 */
		if (frame_status & ERROR_FLAG)
			dev_dbg(core->dev, "Buffer %d decode error\n",
				buffer_index);

		if (pic_struct == PIC_TOP_BOT)
			field = V4L2_FIELD_INTERLACED_TB;
		else if (pic_struct == PIC_BOT_TOP)
			field = V4L2_FIELD_INTERLACED_BT;

		offset |= get_offset_msb(core, i);
		amvdec_dst_buf_done_idx(sess, buffer_index, offset, field);
	}
}

static irqreturn_t codec_h264_threaded_isr(struct amvdec_session *sess)
{
	struct amvdec_core *core = sess->core;
	u32 status;
	u32 size;
	u8 cmd;

	status = amvdec_read_dos(core, AV_SCRATCH_0);
	cmd = status & CMD_MASK;

	switch (cmd) {
	case CMD_SRC_CHANGE:
		codec_h264_src_change(sess);
		break;
	case CMD_FRAMES_READY:
		codec_h264_frames_ready(sess, status);
		break;
	case CMD_FATAL_ERROR:
		dev_err(core->dev, "H.264 decoder fatal error\n");
		goto abort;
	case CMD_BAD_WIDTH:
		size = (amvdec_read_dos(core, AV_SCRATCH_1) + 1) * 16;
		dev_err(core->dev, "Unsupported video width: %u\n", size);
		goto abort;
	case CMD_BAD_HEIGHT:
		size = (amvdec_read_dos(core, AV_SCRATCH_1) + 1) * 16;
		dev_err(core->dev, "Unsupported video height: %u\n", size);
		goto abort;
	case 0: /* Unused but not worth printing for */
	case 9:
		break;
	default:
		dev_info(core->dev, "Unexpected H264 ISR: %08X\n", cmd);
		break;
	}

	if (cmd && cmd != CMD_SRC_CHANGE)
		amvdec_write_dos(core, AV_SCRATCH_0, 0);

	/* Decoder has some SEI data for us ; ignore */
	if (amvdec_read_dos(core, AV_SCRATCH_J) & SEI_DATA_READY)
		amvdec_write_dos(core, AV_SCRATCH_J, 0);

	return IRQ_HANDLED;
abort:
	amvdec_abort(sess);
	return IRQ_HANDLED;
}

static irqreturn_t codec_h264_isr(struct amvdec_session *sess)
{
	struct amvdec_core *core = sess->core;

	amvdec_write_dos(core, ASSIST_MBOX1_CLR_REG, 1);

	return IRQ_WAKE_THREAD;
}

struct amvdec_codec_ops codec_h264_ops = {
	.start = codec_h264_start,
	.stop = codec_h264_stop,
	.load_extended_firmware = codec_h264_load_extended_firmware,
	.isr = codec_h264_isr,
	.threaded_isr = codec_h264_threaded_isr,
	.can_recycle = codec_h264_can_recycle,
	.recycle = codec_h264_recycle,
	.eos_sequence = codec_h264_eos_sequence,
	.resume = codec_h264_resume,
}