// SPDX-License-Identifier: GPL-2.0
//
// Ingenic JZ47xx IPU driver
//
// Copyright (C) 2020, Paul Cercueil <paul@crapouillou.net>
// Copyright (C) 2020, Daniel Silsby <dansilsby@gmail.com>

#include "ingenic-drm.h"
#include "ingenic-ipu.h"

#include <linux/clk.h>
#include <linux/component.h>
#include <linux/gcd.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/regmap.h>
#include <linux/time.h>

#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_damage_helper.h>
#include <drm/drm_drv.h>
#include <drm/drm_fb_cma_helper.h>
#include <drm/drm_fourcc.h>
#include <drm/drm_gem_atomic_helper.h>
#include <drm/drm_gem_cma_helper.h>
#include <drm/drm_gem_framebuffer_helper.h>
#include <drm/drm_plane.h>
#include <drm/drm_plane_helper.h>
#include <drm/drm_property.h>
#include <drm/drm_vblank.h>

struct ingenic_ipu;

struct soc_info {
        const u32 *formats;
        size_t num_formats;
        bool has_bicubic;
        bool manual_restart;

        void (*set_coefs)(struct ingenic_ipu *ipu, unsigned int reg,
                          unsigned int sharpness, bool downscale,
                          unsigned int weight, unsigned int offset);
};

struct ingenic_ipu {
        struct drm_plane plane;
        struct drm_device *drm;
        struct device *dev, *master;
        struct regmap *map;
        struct clk *clk;
        const struct soc_info *soc_info;
        bool clk_enabled;

        unsigned int num_w, num_h, denom_w, denom_h;

        dma_addr_t addr_y, addr_u, addr_v;

        struct drm_property *sharpness_prop;
        unsigned int sharpness;
};

/* Signed 15.16 fixed-point math (for bicubic scaling coefficients) */
#define I2F(i) ((s32)(i) * 65536)
#define F2I(f) ((f) / 65536)
#define FMUL(fa, fb) ((s32)(((s64)(fa) * (s64)(fb)) / 65536))
#define SHARPNESS_INCR (I2F(-1) / 8)

static inline struct ingenic_ipu *plane_to_ingenic_ipu(struct drm_plane *plane)
{
        return container_of(plane, struct ingenic_ipu, plane);
}

/*
 * Apply conventional cubic convolution kernel. Both parameters
 *  and return value are 15.16 signed fixed-point.
 *
 *  @f_a: Sharpness factor, typically in range [-4.0, -0.25].
 *        A larger magnitude increases perceived sharpness, but going past
 *        -2.0 might cause ringing artifacts to outweigh any improvement.
 *        Nice values on a 320x240 LCD are between -0.75 and -2.0.
 *
 *  @f_x: Absolute distance in pixels from 'pixel 0' sample position
 *        along horizontal (or vertical) source axis. Range is [0, +2.0].
 *
 *  returns: Weight of this pixel within 4-pixel sample group. Range is
 *           [-2.0, +2.0]. For moderate (i.e. > -3.0) sharpness factors,
 *           range is within [-1.0, +1.0].
 */
static inline s32 cubic_conv(s32 f_a, s32 f_x)
{
        const s32 f_1 = I2F(1);
        const s32 f_2 = I2F(2);
        const s32 f_3 = I2F(3);
        const s32 f_4 = I2F(4);
        const s32 f_x2 = FMUL(f_x, f_x);
        const s32 f_x3 = FMUL(f_x, f_x2);

        if (f_x <= f_1)
                return FMUL((f_a + f_2), f_x3) - FMUL((f_a + f_3), f_x2) + f_1;
        else if (f_x <= f_2)
                return FMUL(f_a, (f_x3 - 5 * f_x2 + 8 * f_x - f_4));
        else
                return 0;
}

/*
 * On entry, "weight" is a coefficient suitable for bilinear mode,
 *  which is converted to a set of four suitable for bicubic mode.
 *
 * "weight 512" means all of pixel 0;
 * "weight 256" means half of pixel 0 and half of pixel 1;
 * "weight 0" means all of pixel 1;
 *
 * "offset" is increment to next source pixel sample location.
 */
static void jz4760_set_coefs(struct ingenic_ipu *ipu, unsigned int reg,
                             unsigned int sharpness, bool downscale,
                             unsigned int weight, unsigned int offset)
{
        u32 val;
        s32 w0, w1, w2, w3; /* Pixel weights at X (or Y) offsets -1,0,1,2 */

        weight = clamp_val(weight, 0, 512);

        if (sharpness < 2) {
                /*
                 *  When sharpness setting is 0, emulate nearest-neighbor.
                 *  When sharpness setting is 1, emulate bilinear.
                 */

                if (sharpness == 0)
                        weight = weight >= 256 ? 512 : 0;
                w0 = 0;
                w1 = weight;
                w2 = 512 - weight;
                w3 = 0;
        } else {
                const s32 f_a = SHARPNESS_INCR * sharpness;
                const s32 f_h = I2F(1) / 2; /* Round up 0.5 */

                /*
                 * Note that always rounding towards +infinity here is intended.
                 * The resulting coefficients match a round-to-nearest-int
                 * double floating-point implementation.
                 */

                weight = 512 - weight;
                w0 = F2I(f_h + 512 * cubic_conv(f_a, I2F(512  + weight) / 512));
                w1 = F2I(f_h + 512 * cubic_conv(f_a, I2F(0    + weight) / 512));
                w2 = F2I(f_h + 512 * cubic_conv(f_a, I2F(512  - weight) / 512));
                w3 = F2I(f_h + 512 * cubic_conv(f_a, I2F(1024 - weight) / 512));
                w0 = clamp_val(w0, -1024, 1023);
                w1 = clamp_val(w1, -1024, 1023);
                w2 = clamp_val(w2, -1024, 1023);
                w3 = clamp_val(w3, -1024, 1023);
        }

        val = ((w1 & JZ4760_IPU_RSZ_COEF_MASK) << JZ4760_IPU_RSZ_COEF31_LSB) |
                ((w0 & JZ4760_IPU_RSZ_COEF_MASK) << JZ4760_IPU_RSZ_COEF20_LSB);
        regmap_write(ipu->map, reg, val);

        val = ((w3 & JZ4760_IPU_RSZ_COEF_MASK) << JZ4760_IPU_RSZ_COEF31_LSB) |
                ((w2 & JZ4760_IPU_RSZ_COEF_MASK) << JZ4760_IPU_RSZ_COEF20_LSB) |
                ((offset & JZ4760_IPU_RSZ_OFFSET_MASK) << JZ4760_IPU_RSZ_OFFSET_LSB);
        regmap_write(ipu->map, reg, val);
}

static void jz4725b_set_coefs(struct ingenic_ipu *ipu, unsigned int reg,
                              unsigned int sharpness, bool downscale,
                              unsigned int weight, unsigned int offset)
{
        u32 val = JZ4725B_IPU_RSZ_LUT_OUT_EN;
        unsigned int i;

        weight = clamp_val(weight, 0, 512);

        if (sharpness == 0)
                weight = weight >= 256 ? 512 : 0;

        val |= (weight & JZ4725B_IPU_RSZ_LUT_COEF_MASK) << JZ4725B_IPU_RSZ_LUT_COEF_LSB;
        if (downscale || !!offset)
                val |= JZ4725B_IPU_RSZ_LUT_IN_EN;

        regmap_write(ipu->map, reg, val);

        if (downscale) {
                for (i = 1; i < offset; i++)
                        regmap_write(ipu->map, reg, JZ4725B_IPU_RSZ_LUT_IN_EN);
        }
}

static void ingenic_ipu_set_downscale_coefs(struct ingenic_ipu *ipu,
                                            unsigned int reg,
                                            unsigned int num,
                                            unsigned int denom)
{
        unsigned int i, offset, weight, weight_num = denom;

        for (i = 0; i < num; i++) {
                weight_num = num + (weight_num - num) % (num * 2);
                weight = 512 - 512 * (weight_num - num) / (num * 2);
                weight_num += denom * 2;
                offset = (weight_num - num) / (num * 2);

                ipu->soc_info->set_coefs(ipu, reg, ipu->sharpness,
                                         true, weight, offset);
        }
}

static void ingenic_ipu_set_integer_upscale_coefs(struct ingenic_ipu *ipu,
                                                  unsigned int reg,
                                                  unsigned int num)
{
        /*
         * Force nearest-neighbor scaling and use simple math when upscaling
         * by an integer ratio. It looks better, and fixes a few problem cases.
         */
        unsigned int i;

        for (i = 0; i < num; i++)
                ipu->soc_info->set_coefs(ipu, reg, 0, false, 512, i == num - 1);
}

static void ingenic_ipu_set_upscale_coefs(struct ingenic_ipu *ipu,
                                          unsigned int reg,
                                          unsigned int num,
                                          unsigned int denom)
{
        unsigned int i, offset, weight, weight_num = 0;

        for (i = 0; i < num; i++) {
                weight = 512 - 512 * weight_num / num;
                weight_num += denom;
                offset = weight_num >= num;

                if (offset)
                        weight_num -= num;

                ipu->soc_info->set_coefs(ipu, reg, ipu->sharpness,
                                         false, weight, offset);
        }
}

static void ingenic_ipu_set_coefs(struct ingenic_ipu *ipu, unsigned int reg,
                                  unsigned int num, unsigned int denom)
{
        /* Begin programming the LUT */
        regmap_write(ipu->map, reg, -1);

        if (denom > num)
                ingenic_ipu_set_downscale_coefs(ipu, reg, num, denom);
        else if (denom == 1)
                ingenic_ipu_set_integer_upscale_coefs(ipu, reg, num);
        else
                ingenic_ipu_set_upscale_coefs(ipu, reg, num, denom);
}

static int reduce_fraction(unsigned int *num, unsigned int *denom)
{
        unsigned long d = gcd(*num, *denom);

        /* The scaling table has only 31 entries */
        if (*num > 31 * d)
                return -EINVAL;

        *num /= d;
        *denom /= d;
        return 0;
}

static inline bool osd_changed(struct drm_plane_state *state,
                               struct drm_plane_state *oldstate)
{
        return state->src_x != oldstate->src_x ||
                state->src_y != oldstate->src_y ||
                state->src_w != oldstate->src_w ||
                state->src_h != oldstate->src_h ||
                state->crtc_x != oldstate->crtc_x ||
                state->crtc_y != oldstate->crtc_y ||
                state->crtc_w != oldstate->crtc_w ||
                state->crtc_h != oldstate->crtc_h;
}

static void ingenic_ipu_plane_atomic_update(struct drm_plane *plane,
                                            struct drm_atomic_state *state)
{
        struct ingenic_ipu *ipu = plane_to_ingenic_ipu(plane);
        struct drm_plane_state *newstate = drm_atomic_get_new_plane_state(state, plane);
        struct drm_plane_state *oldstate = drm_atomic_get_old_plane_state(state, plane);
        const struct drm_format_info *finfo;
        u32 ctrl, stride = 0, coef_index = 0, format = 0;
        bool needs_modeset, upscaling_w, upscaling_h;
        int err;

        if (!newstate || !newstate->fb)
                return;

        finfo = drm_format_info(newstate->fb->format->format);

        if (!ipu->clk_enabled) {
                err = clk_enable(ipu->clk);
                if (err) {
                        dev_err(ipu->dev, "Unable to enable clock: %d\n", err);
                        return;
                }

                ipu->clk_enabled = true;
        }

        /* Reset all the registers if needed */
        needs_modeset = drm_atomic_crtc_needs_modeset(newstate->crtc->state);
        if (needs_modeset) {
                regmap_set_bits(ipu->map, JZ_REG_IPU_CTRL, JZ_IPU_CTRL_RST);

                /* Enable the chip */
                regmap_set_bits(ipu->map, JZ_REG_IPU_CTRL,
                                JZ_IPU_CTRL_CHIP_EN | JZ_IPU_CTRL_LCDC_SEL);
        }

        if (ingenic_drm_map_noncoherent(ipu->master))
                drm_fb_cma_sync_non_coherent(ipu->drm, oldstate, newstate);

        /* New addresses will be committed in vblank handler... */
        ipu->addr_y = drm_fb_cma_get_gem_addr(newstate->fb, newstate, 0);
        if (finfo->num_planes > 1)
                ipu->addr_u = drm_fb_cma_get_gem_addr(newstate->fb, newstate,
                                                      1);
        if (finfo->num_planes > 2)
                ipu->addr_v = drm_fb_cma_get_gem_addr(newstate->fb, newstate,
                                                      2);

        if (!needs_modeset)
                return;

        /* Or right here if we're doing a full modeset. */
        regmap_write(ipu->map, JZ_REG_IPU_Y_ADDR, ipu->addr_y);
        regmap_write(ipu->map, JZ_REG_IPU_U_ADDR, ipu->addr_u);
        regmap_write(ipu->map, JZ_REG_IPU_V_ADDR, ipu->addr_v);

        if (finfo->num_planes == 1)
                regmap_set_bits(ipu->map, JZ_REG_IPU_CTRL, JZ_IPU_CTRL_SPKG_SEL);

        ingenic_drm_plane_config(ipu->master, plane, DRM_FORMAT_XRGB8888);

        /* Set the input height/width/strides */
        if (finfo->num_planes > 2)
                stride = ((newstate->src_w >> 16) * finfo->cpp[2] / finfo->hsub)
                        << JZ_IPU_UV_STRIDE_V_LSB;

        if (finfo->num_planes > 1)
                stride |= ((newstate->src_w >> 16) * finfo->cpp[1] / finfo->hsub)
                        << JZ_IPU_UV_STRIDE_U_LSB;

        regmap_write(ipu->map, JZ_REG_IPU_UV_STRIDE, stride);

        stride = ((newstate->src_w >> 16) * finfo->cpp[0]) << JZ_IPU_Y_STRIDE_Y_LSB;
        regmap_write(ipu->map, JZ_REG_IPU_Y_STRIDE, stride);

        regmap_write(ipu->map, JZ_REG_IPU_IN_GS,
                     (stride << JZ_IPU_IN_GS_W_LSB) |
                     ((newstate->src_h >> 16) << JZ_IPU_IN_GS_H_LSB));

        switch (finfo->format) {
        case DRM_FORMAT_XRGB1555:
                format = JZ_IPU_D_FMT_IN_FMT_RGB555 |
                        JZ_IPU_D_FMT_RGB_OUT_OFT_RGB;
                break;
        case DRM_FORMAT_XBGR1555:
                format = JZ_IPU_D_FMT_IN_FMT_RGB555 |
                        JZ_IPU_D_FMT_RGB_OUT_OFT_BGR;
                break;
        case DRM_FORMAT_RGB565:
                format = JZ_IPU_D_FMT_IN_FMT_RGB565 |
                        JZ_IPU_D_FMT_RGB_OUT_OFT_RGB;
                break;
        case DRM_FORMAT_BGR565:
                format = JZ_IPU_D_FMT_IN_FMT_RGB565 |
                        JZ_IPU_D_FMT_RGB_OUT_OFT_BGR;
                break;
        case DRM_FORMAT_XRGB8888:
        case DRM_FORMAT_XYUV8888:
                format = JZ_IPU_D_FMT_IN_FMT_RGB888 |
                        JZ_IPU_D_FMT_RGB_OUT_OFT_RGB;
                break;
        case DRM_FORMAT_XBGR8888:
                format = JZ_IPU_D_FMT_IN_FMT_RGB888 |
                        JZ_IPU_D_FMT_RGB_OUT_OFT_BGR;
                break;
        case DRM_FORMAT_YUYV:
                format = JZ_IPU_D_FMT_IN_FMT_YUV422 |
                        JZ_IPU_D_FMT_YUV_VY1UY0;
                break;
        case DRM_FORMAT_YVYU:
                format = JZ_IPU_D_FMT_IN_FMT_YUV422 |
                        JZ_IPU_D_FMT_YUV_UY1VY0;
                break;
        case DRM_FORMAT_UYVY:
                format = JZ_IPU_D_FMT_IN_FMT_YUV422 |
                        JZ_IPU_D_FMT_YUV_Y1VY0U;
                break;
        case DRM_FORMAT_VYUY:
                format = JZ_IPU_D_FMT_IN_FMT_YUV422 |
                        JZ_IPU_D_FMT_YUV_Y1UY0V;
                break;
        case DRM_FORMAT_YUV411:
                format = JZ_IPU_D_FMT_IN_FMT_YUV411;
                break;
        case DRM_FORMAT_YUV420:
                format = JZ_IPU_D_FMT_IN_FMT_YUV420;
                break;
        case DRM_FORMAT_YUV422:
                format = JZ_IPU_D_FMT_IN_FMT_YUV422;
                break;
        case DRM_FORMAT_YUV444:
                format = JZ_IPU_D_FMT_IN_FMT_YUV444;
                break;
        default:
                WARN_ONCE(1, "Unsupported format");
                break;
        }

        /* Fix output to RGB888 */
        format |= JZ_IPU_D_FMT_OUT_FMT_RGB888;

        /* Set pixel format */
        regmap_write(ipu->map, JZ_REG_IPU_D_FMT, format);

        /* Set the output height/width/stride */
        regmap_write(ipu->map, JZ_REG_IPU_OUT_GS,
                     ((newstate->crtc_w * 4) << JZ_IPU_OUT_GS_W_LSB)
                     | newstate->crtc_h << JZ_IPU_OUT_GS_H_LSB);
        regmap_write(ipu->map, JZ_REG_IPU_OUT_STRIDE, newstate->crtc_w * 4);

        if (finfo->is_yuv) {
                regmap_set_bits(ipu->map, JZ_REG_IPU_CTRL, JZ_IPU_CTRL_CSC_EN);

                /*
                 * Offsets for Chroma/Luma.
                 * y = source Y - LUMA,
                 * u = source Cb - CHROMA,
                 * v = source Cr - CHROMA
                 */
                regmap_write(ipu->map, JZ_REG_IPU_CSC_OFFSET,
                             128 << JZ_IPU_CSC_OFFSET_CHROMA_LSB |
                             0 << JZ_IPU_CSC_OFFSET_LUMA_LSB);

                /*
                 * YUV422 to RGB conversion table.
                 * R = C0 / 0x400 * y + C1 / 0x400 * v
                 * G = C0 / 0x400 * y - C2 / 0x400 * u - C3 / 0x400 * v
                 * B = C0 / 0x400 * y + C4 / 0x400 * u
                 */
                regmap_write(ipu->map, JZ_REG_IPU_CSC_C0_COEF, 0x4a8);
                regmap_write(ipu->map, JZ_REG_IPU_CSC_C1_COEF, 0x662);
                regmap_write(ipu->map, JZ_REG_IPU_CSC_C2_COEF, 0x191);
                regmap_write(ipu->map, JZ_REG_IPU_CSC_C3_COEF, 0x341);
                regmap_write(ipu->map, JZ_REG_IPU_CSC_C4_COEF, 0x811);
        }

        ctrl = 0;

        /*
         * Must set ZOOM_SEL before programming bicubic LUTs.
         * If the IPU supports bicubic, we enable it unconditionally, since it
         * can do anything bilinear can and more.
         */
        if (ipu->soc_info->has_bicubic)
                ctrl |= JZ_IPU_CTRL_ZOOM_SEL;

        upscaling_w = ipu->num_w > ipu->denom_w;
        if (upscaling_w)
                ctrl |= JZ_IPU_CTRL_HSCALE;

        if (ipu->num_w != 1 || ipu->denom_w != 1) {
                if (!ipu->soc_info->has_bicubic && !upscaling_w)
                        coef_index |= (ipu->denom_w - 1) << 16;
                else
                        coef_index |= (ipu->num_w - 1) << 16;
                ctrl |= JZ_IPU_CTRL_HRSZ_EN;
        }

        upscaling_h = ipu->num_h > ipu->denom_h;
        if (upscaling_h)
                ctrl |= JZ_IPU_CTRL_VSCALE;

        if (ipu->num_h != 1 || ipu->denom_h != 1) {
                if (!ipu->soc_info->has_bicubic && !upscaling_h)
                        coef_index |= ipu->denom_h - 1;
                else
                        coef_index |= ipu->num_h - 1;
                ctrl |= JZ_IPU_CTRL_VRSZ_EN;
        }

        regmap_update_bits(ipu->map, JZ_REG_IPU_CTRL, JZ_IPU_CTRL_ZOOM_SEL |
                           JZ_IPU_CTRL_HRSZ_EN | JZ_IPU_CTRL_VRSZ_EN |
                           JZ_IPU_CTRL_HSCALE | JZ_IPU_CTRL_VSCALE, ctrl);

        /* Set the LUT index register */
        regmap_write(ipu->map, JZ_REG_IPU_RSZ_COEF_INDEX, coef_index);

        if (ipu->num_w != 1 || ipu->denom_w != 1)
                ingenic_ipu_set_coefs(ipu, JZ_REG_IPU_HRSZ_COEF_LUT,
                                      ipu->num_w, ipu->denom_w);

        if (ipu->num_h != 1 || ipu->denom_h != 1)
                ingenic_ipu_set_coefs(ipu, JZ_REG_IPU_VRSZ_COEF_LUT,
                                      ipu->num_h, ipu->denom_h);

        /* Clear STATUS register */
        regmap_write(ipu->map, JZ_REG_IPU_STATUS, 0);

        /* Start IPU */
        regmap_set_bits(ipu->map, JZ_REG_IPU_CTRL,
                        JZ_IPU_CTRL_RUN | JZ_IPU_CTRL_FM_IRQ_EN);

        dev_dbg(ipu->dev, "Scaling %ux%u to %ux%u (%u:%u horiz, %u:%u vert)\n",
                newstate->src_w >> 16, newstate->src_h >> 16,
                newstate->crtc_w, newstate->crtc_h,
                ipu->num_w, ipu->denom_w, ipu->num_h, ipu->denom_h);
}

static int ingenic_ipu_plane_atomic_check(struct drm_plane *plane,
                                          struct drm_atomic_state *state)
{
        struct drm_plane_state *old_plane_state = drm_atomic_get_old_plane_state(state,
                                                                                 plane);
        struct drm_plane_state *new_plane_state = drm_atomic_get_new_plane_state(state,
                                                                                 plane);
        unsigned int num_w, denom_w, num_h, denom_h, xres, yres, max_w, max_h;
        struct ingenic_ipu *ipu = plane_to_ingenic_ipu(plane);
        struct drm_crtc *crtc = new_plane_state->crtc ?: old_plane_state->crtc;
        struct drm_crtc_state *crtc_state;

        if (!crtc)
                return 0;

        crtc_state = drm_atomic_get_existing_crtc_state(state, crtc);
        if (WARN_ON(!crtc_state))
                return -EINVAL;

        /* Request a full modeset if we are enabling or disabling the IPU. */
        if (!old_plane_state->crtc ^ !new_plane_state->crtc)
                crtc_state->mode_changed = true;

        if (!new_plane_state->crtc ||
            !crtc_state->mode.hdisplay || !crtc_state->mode.vdisplay)
                goto out_check_damage;

        /* Plane must be fully visible */
        if (new_plane_state->crtc_x < 0 || new_plane_state->crtc_y < 0 ||
            new_plane_state->crtc_x + new_plane_state->crtc_w > crtc_state->mode.hdisplay ||
            new_plane_state->crtc_y + new_plane_state->crtc_h > crtc_state->mode.vdisplay)
                return -EINVAL;

        /* Minimum size is 4x4 */
        if ((new_plane_state->src_w >> 16) < 4 || (new_plane_state->src_h >> 16) < 4)
                return -EINVAL;

        /* Input and output lines must have an even number of pixels. */
        if (((new_plane_state->src_w >> 16) & 1) || (new_plane_state->crtc_w & 1))
                return -EINVAL;

        if (!osd_changed(new_plane_state, old_plane_state))
                goto out_check_damage;

        crtc_state->mode_changed = true;

        xres = new_plane_state->src_w >> 16;
        yres = new_plane_state->src_h >> 16;

        /*
         * Increase the scaled image's theorical width/height until we find a
         * configuration that has valid scaling coefficients, up to 102% of the
         * screen's resolution. This makes sure that we can scale from almost
         * every resolution possible at the cost of a very small distorsion.
         * The CRTC_W / CRTC_H are not modified.
         */
        max_w = crtc_state->mode.hdisplay * 102 / 100;
        max_h = crtc_state->mode.vdisplay * 102 / 100;

        for (denom_w = xres, num_w = new_plane_state->crtc_w; num_w <= max_w; num_w++)
                if (!reduce_fraction(&num_w, &denom_w))
                        break;
        if (num_w > max_w)
                return -EINVAL;

        for (denom_h = yres, num_h = new_plane_state->crtc_h; num_h <= max_h; num_h++)
                if (!reduce_fraction(&num_h, &denom_h))
                        break;
        if (num_h > max_h)
                return -EINVAL;

        ipu->num_w = num_w;
        ipu->num_h = num_h;
        ipu->denom_w = denom_w;
        ipu->denom_h = denom_h;

out_check_damage:
        if (ingenic_drm_map_noncoherent(ipu->master))
                drm_atomic_helper_check_plane_damage(state, new_plane_state);

        return 0;
}

static void ingenic_ipu_plane_atomic_disable(struct drm_plane *plane,
                                             struct drm_atomic_state *state)
{
        struct ingenic_ipu *ipu = plane_to_ingenic_ipu(plane);

        regmap_set_bits(ipu->map, JZ_REG_IPU_CTRL, JZ_IPU_CTRL_STOP);
        regmap_clear_bits(ipu->map, JZ_REG_IPU_CTRL, JZ_IPU_CTRL_CHIP_EN);

        ingenic_drm_plane_disable(ipu->master, plane);

        if (ipu->clk_enabled) {
                clk_disable(ipu->clk);
                ipu->clk_enabled = false;
        }
}

static const struct drm_plane_helper_funcs ingenic_ipu_plane_helper_funcs = {
        .atomic_update          = ingenic_ipu_plane_atomic_update,
        .atomic_check           = ingenic_ipu_plane_atomic_check,
        .atomic_disable         = ingenic_ipu_plane_atomic_disable,
};

static int
ingenic_ipu_plane_atomic_get_property(struct drm_plane *plane,
                                      const struct drm_plane_state *state,
                                      struct drm_property *property, u64 *val)
{
        struct ingenic_ipu *ipu = plane_to_ingenic_ipu(plane);

        if (property != ipu->sharpness_prop)
                return -EINVAL;

        *val = ipu->sharpness;

        return 0;
}

static int
ingenic_ipu_plane_atomic_set_property(struct drm_plane *plane,
                                      struct drm_plane_state *state,
                                      struct drm_property *property, u64 val)
{
        struct ingenic_ipu *ipu = plane_to_ingenic_ipu(plane);
        struct drm_crtc_state *crtc_state;

        if (property != ipu->sharpness_prop)
                return -EINVAL;

        ipu->sharpness = val;

        if (state->crtc) {
                crtc_state = drm_atomic_get_existing_crtc_state(state->state, state->crtc);
                if (WARN_ON(!crtc_state))
                        return -EINVAL;

                crtc_state->mode_changed = true;
        }

        return 0;
}

static const struct drm_plane_funcs ingenic_ipu_plane_funcs = {
        .update_plane           = drm_atomic_helper_update_plane,
        .disable_plane          = drm_atomic_helper_disable_plane,
        .reset                  = drm_atomic_helper_plane_reset,
        .destroy                = drm_plane_cleanup,

        .atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
        .atomic_destroy_state   = drm_atomic_helper_plane_destroy_state,

        .atomic_get_property    = ingenic_ipu_plane_atomic_get_property,
        .atomic_set_property    = ingenic_ipu_plane_atomic_set_property,
};

static irqreturn_t ingenic_ipu_irq_handler(int irq, void *arg)
{
        struct ingenic_ipu *ipu = arg;
        struct drm_crtc *crtc = drm_crtc_from_index(ipu->drm, 0);
        unsigned int dummy;

        /* dummy read allows CPU to reconfigure IPU */
        if (ipu->soc_info->manual_restart)
                regmap_read(ipu->map, JZ_REG_IPU_STATUS, &dummy);

        /* ACK interrupt */
        regmap_write(ipu->map, JZ_REG_IPU_STATUS, 0);

        /* Set previously cached addresses */
        regmap_write(ipu->map, JZ_REG_IPU_Y_ADDR, ipu->addr_y);
        regmap_write(ipu->map, JZ_REG_IPU_U_ADDR, ipu->addr_u);
        regmap_write(ipu->map, JZ_REG_IPU_V_ADDR, ipu->addr_v);

        /* Run IPU for the new frame */
        if (ipu->soc_info->manual_restart)
                regmap_set_bits(ipu->map, JZ_REG_IPU_CTRL, JZ_IPU_CTRL_RUN);

        drm_crtc_handle_vblank(crtc);

        return IRQ_HANDLED;
}

static const struct regmap_config ingenic_ipu_regmap_config = {
        .reg_bits = 32,
        .val_bits = 32,
        .reg_stride = 4,

        .max_register = JZ_REG_IPU_OUT_PHY_T_ADDR,
};

static int ingenic_ipu_bind(struct device *dev, struct device *master, void *d)
{
        struct platform_device *pdev = to_platform_device(dev);
        const struct soc_info *soc_info;
        struct drm_device *drm = d;
        struct drm_plane *plane;
        struct ingenic_ipu *ipu;
        void __iomem *base;
        unsigned int sharpness_max;
        int err, irq;

        ipu = devm_kzalloc(dev, sizeof(*ipu), GFP_KERNEL);
        if (!ipu)
                return -ENOMEM;

        soc_info = of_device_get_match_data(dev);
        if (!soc_info) {
                dev_err(dev, "Missing platform data\n");
                return -EINVAL;
        }

        ipu->dev = dev;
        ipu->drm = drm;
        ipu->master = master;
        ipu->soc_info = soc_info;

        base = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(base)) {
                dev_err(dev, "Failed to get memory resource\n");
                return PTR_ERR(base);
        }

        ipu->map = devm_regmap_init_mmio(dev, base, &ingenic_ipu_regmap_config);
        if (IS_ERR(ipu->map)) {
                dev_err(dev, "Failed to create regmap\n");
                return PTR_ERR(ipu->map);
        }

        irq = platform_get_irq(pdev, 0);
        if (irq < 0)
                return irq;

        ipu->clk = devm_clk_get(dev, "ipu");
        if (IS_ERR(ipu->clk)) {
                dev_err(dev, "Failed to get pixel clock\n");
                return PTR_ERR(ipu->clk);
        }

        err = devm_request_irq(dev, irq, ingenic_ipu_irq_handler, 0,
                               dev_name(dev), ipu);
        if (err) {
                dev_err(dev, "Unable to request IRQ\n");
                return err;
        }

        plane = &ipu->plane;
        dev_set_drvdata(dev, plane);

        drm_plane_helper_add(plane, &ingenic_ipu_plane_helper_funcs);

        err = drm_universal_plane_init(drm, plane, 1, &ingenic_ipu_plane_funcs,
                                       soc_info->formats, soc_info->num_formats,
                                       NULL, DRM_PLANE_TYPE_OVERLAY, NULL);
        if (err) {
                dev_err(dev, "Failed to init plane: %i\n", err);
                return err;
        }

        if (ingenic_drm_map_noncoherent(master))
                drm_plane_enable_fb_damage_clips(plane);

        /*
         * Sharpness settings range is [0,32]
         * 0       : nearest-neighbor
         * 1       : bilinear
         * 2 .. 32 : bicubic (translated to sharpness factor -0.25 .. -4.0)
         */
        sharpness_max = soc_info->has_bicubic ? 32 : 1;
        ipu->sharpness_prop = drm_property_create_range(drm, 0, "sharpness",
                                                        0, sharpness_max);
        if (!ipu->sharpness_prop) {
                dev_err(dev, "Unable to create sharpness property\n");
                return -ENOMEM;
        }

        /* Default sharpness factor: -0.125 * 8 = -1.0 */
        ipu->sharpness = soc_info->has_bicubic ? 8 : 1;
        drm_object_attach_property(&plane->base, ipu->sharpness_prop,
                                   ipu->sharpness);

        err = clk_prepare(ipu->clk);
        if (err) {
                dev_err(dev, "Unable to prepare clock\n");
                return err;
        }

        return 0;
}

static void ingenic_ipu_unbind(struct device *dev,
                               struct device *master, void *d)
{
        struct ingenic_ipu *ipu = dev_get_drvdata(dev);

        clk_unprepare(ipu->clk);
}

static const struct component_ops ingenic_ipu_ops = {
        .bind = ingenic_ipu_bind,
        .unbind = ingenic_ipu_unbind,
};

static int ingenic_ipu_probe(struct platform_device *pdev)
{
        return component_add(&pdev->dev, &ingenic_ipu_ops);
}

static int ingenic_ipu_remove(struct platform_device *pdev)
{
        component_del(&pdev->dev, &ingenic_ipu_ops);
        return 0;
}

static const u32 jz4725b_ipu_formats[] = {
        /*
         * While officially supported, packed YUV 4:2:2 formats can cause
         * random hardware crashes on JZ4725B under certain circumstances.
         * It seems to happen with some specific resize ratios.
         * Until a proper workaround or fix is found, disable these formats.
        DRM_FORMAT_YUYV,
        DRM_FORMAT_YVYU,
        DRM_FORMAT_UYVY,
        DRM_FORMAT_VYUY,
        */
        DRM_FORMAT_YUV411,
        DRM_FORMAT_YUV420,
        DRM_FORMAT_YUV422,
        DRM_FORMAT_YUV444,
};

static const struct soc_info jz4725b_soc_info = {
        .formats        = jz4725b_ipu_formats,
        .num_formats    = ARRAY_SIZE(jz4725b_ipu_formats),
        .has_bicubic    = false,
        .manual_restart = true,
        .set_coefs      = jz4725b_set_coefs,
};

static const u32 jz4760_ipu_formats[] = {
        DRM_FORMAT_XRGB1555,
        DRM_FORMAT_XBGR1555,
        DRM_FORMAT_RGB565,
        DRM_FORMAT_BGR565,
        DRM_FORMAT_XRGB8888,
        DRM_FORMAT_XBGR8888,
        DRM_FORMAT_YUYV,
        DRM_FORMAT_YVYU,
        DRM_FORMAT_UYVY,
        DRM_FORMAT_VYUY,
        DRM_FORMAT_YUV411,
        DRM_FORMAT_YUV420,
        DRM_FORMAT_YUV422,
        DRM_FORMAT_YUV444,
        DRM_FORMAT_XYUV8888,
};

static const struct soc_info jz4760_soc_info = {
        .formats        = jz4760_ipu_formats,
        .num_formats    = ARRAY_SIZE(jz4760_ipu_formats),
        .has_bicubic    = true,
        .manual_restart = false,
        .set_coefs      = jz4760_set_coefs,
};

static const struct of_device_id ingenic_ipu_of_match[] = {
        { .compatible = "ingenic,jz4725b-ipu", .data = &jz4725b_soc_info },
        { .compatible = "ingenic,jz4760-ipu", .data = &jz4760_soc_info },
        { /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, ingenic_ipu_of_match);

static struct platform_driver ingenic_ipu_driver = {
        .driver = {
                .name = "ingenic-ipu",
                .of_match_table = ingenic_ipu_of_match,
        },
        .probe = ingenic_ipu_probe,
        .remove = ingenic_ipu_remove,
};

struct platform_driver *ingenic_ipu_driver_ptr = &ingenic_ipu_driver;