drivers/gpu/ipu-v3/ipu-prg.c - linux - Git at Google

 /*
  * Copyright (c) 2016-2017 Lucas Stach, Pengutronix
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
  * version 2, as published by the Free Software Foundation.
  *
  * This program is distributed in the hope it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  * more details.
  */

 #include <drm/drm_fourcc.h>
 #include <linux/clk.h>
 #include <linux/err.h>
 #include <linux/iopoll.h>
 #include <linux/mfd/syscon.h>
 #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/regmap.h>
 #include <video/imx-ipu-v3.h>

 #include "ipu-prv.h"

 #define IPU_PRG_CTL				0x00
 #define  IPU_PRG_CTL_BYPASS(i)			(1 << (0 + i))
 #define  IPU_PRG_CTL_SOFT_ARID_MASK		0x3
 #define  IPU_PRG_CTL_SOFT_ARID_SHIFT(i)		(8 + i * 2)
 #define  IPU_PRG_CTL_SOFT_ARID(i, v)		((v & 0x3) << (8 + 2 * i))
 #define  IPU_PRG_CTL_SO(i)			(1 << (16 + i))
 #define  IPU_PRG_CTL_VFLIP(i)			(1 << (19 + i))
 #define  IPU_PRG_CTL_BLOCK_MODE(i)		(1 << (22 + i))
 #define  IPU_PRG_CTL_CNT_LOAD_EN(i)		(1 << (25 + i))
 #define  IPU_PRG_CTL_SOFTRST			(1 << 30)
 #define  IPU_PRG_CTL_SHADOW_EN			(1 << 31)

 #define IPU_PRG_STATUS				0x04
 #define  IPU_PRG_STATUS_BUFFER0_READY(i)	(1 << (0 + i * 2))
 #define  IPU_PRG_STATUS_BUFFER1_READY(i)	(1 << (1 + i * 2))

 #define IPU_PRG_QOS				0x08
 #define  IPU_PRG_QOS_ARID_MASK			0xf
 #define  IPU_PRG_QOS_ARID_SHIFT(i)		(0 + i * 4)

 #define IPU_PRG_REG_UPDATE			0x0c
 #define  IPU_PRG_REG_UPDATE_REG_UPDATE		(1 << 0)

 #define IPU_PRG_STRIDE(i)			(0x10 + i * 0x4)
 #define  IPU_PRG_STRIDE_STRIDE_MASK		0x3fff

 #define IPU_PRG_CROP_LINE			0x1c

 #define IPU_PRG_THD				0x20

 #define IPU_PRG_BADDR(i)			(0x24 + i * 0x4)

 #define IPU_PRG_OFFSET(i)			(0x30 + i * 0x4)

 #define IPU_PRG_ILO(i)				(0x3c + i * 0x4)

 #define IPU_PRG_HEIGHT(i)			(0x48 + i * 0x4)
 #define  IPU_PRG_HEIGHT_PRE_HEIGHT_MASK		0xfff
 #define  IPU_PRG_HEIGHT_PRE_HEIGHT_SHIFT	0
 #define  IPU_PRG_HEIGHT_IPU_HEIGHT_MASK		0xfff
 #define  IPU_PRG_HEIGHT_IPU_HEIGHT_SHIFT	16

 struct ipu_prg_channel {
 	bool			enabled;
 	int			used_pre;
 };

 struct ipu_prg {
 	struct list_head	list;
 	struct device		*dev;
 	int			id;

 	void __iomem		*regs;
 	struct clk		*clk_ipg, *clk_axi;
 	struct regmap		*iomuxc_gpr;
 	struct ipu_pre		*pres[3];

 	struct ipu_prg_channel	chan[3];
 };

 static DEFINE_MUTEX(ipu_prg_list_mutex);
 static LIST_HEAD(ipu_prg_list);

 struct ipu_prg *
 ipu_prg_lookup_by_phandle(struct device *dev, const char *name, int ipu_id)
 {
 	struct device_node *prg_node = of_parse_phandle(dev->of_node,
 							name, 0);
 	struct ipu_prg *prg;

 	mutex_lock(&ipu_prg_list_mutex);
 	list_for_each_entry(prg, &ipu_prg_list, list) {
 		if (prg_node == prg->dev->of_node) {
 			mutex_unlock(&ipu_prg_list_mutex);
 			device_link_add(dev, prg->dev,
 					DL_FLAG_AUTOREMOVE_CONSUMER);
 			prg->id = ipu_id;
 			of_node_put(prg_node);
 			return prg;
 		}
 	}
 	mutex_unlock(&ipu_prg_list_mutex);

 	of_node_put(prg_node);

 	return NULL;
 }

 int ipu_prg_max_active_channels(void)
 {
 	return ipu_pre_get_available_count();
 }
 EXPORT_SYMBOL_GPL(ipu_prg_max_active_channels);

 bool ipu_prg_present(struct ipu_soc *ipu)
 {
 	if (ipu->prg_priv)
 		return true;

 	return false;
 }
 EXPORT_SYMBOL_GPL(ipu_prg_present);

 bool ipu_prg_format_supported(struct ipu_soc *ipu, uint32_t format,
 			      uint64_t modifier)
 {
 	const struct drm_format_info *info = drm_format_info(format);

 	if (info->num_planes != 1)
 		return false;

 	switch (modifier) {
 	case DRM_FORMAT_MOD_LINEAR:
 	case DRM_FORMAT_MOD_VIVANTE_TILED:
 	case DRM_FORMAT_MOD_VIVANTE_SUPER_TILED:
 		return true;
 	default:
 		return false;
 	}
 }
 EXPORT_SYMBOL_GPL(ipu_prg_format_supported);

 int ipu_prg_enable(struct ipu_soc *ipu)
 {
 	struct ipu_prg *prg = ipu->prg_priv;

 	if (!prg)
 		return 0;

 	return pm_runtime_get_sync(prg->dev);
 }
 EXPORT_SYMBOL_GPL(ipu_prg_enable);

 void ipu_prg_disable(struct ipu_soc *ipu)
 {
 	struct ipu_prg *prg = ipu->prg_priv;

 	if (!prg)
 		return;

 	pm_runtime_put(prg->dev);
 }
 EXPORT_SYMBOL_GPL(ipu_prg_disable);

 /*
  * The channel configuartion functions below are not thread safe, as they
  * must be only called from the atomic commit path in the DRM driver, which
  * is properly serialized.
  */
 static int ipu_prg_ipu_to_prg_chan(int ipu_chan)
 {
 	/*
 	 * This isn't clearly documented in the RM, but IPU to PRG channel
 	 * assignment is fixed, as only with this mapping the control signals
 	 * match up.
 	 */
 	switch (ipu_chan) {
 	case IPUV3_CHANNEL_MEM_BG_SYNC:
 		return 0;
 	case IPUV3_CHANNEL_MEM_FG_SYNC:
 		return 1;
 	case IPUV3_CHANNEL_MEM_DC_SYNC:
 		return 2;
 	default:
 		return -EINVAL;
 	}
 }

 static int ipu_prg_get_pre(struct ipu_prg *prg, int prg_chan)
 {
 	int i, ret;

 	/* channel 0 is special as it is hardwired to one of the PREs */
 	if (prg_chan == 0) {
 		ret = ipu_pre_get(prg->pres[0]);
 		if (ret)
 			goto fail;
 		prg->chan[prg_chan].used_pre = 0;
 		return 0;
 	}

 	for (i = 1; i < 3; i++) {
 		ret = ipu_pre_get(prg->pres[i]);
 		if (!ret) {
 			u32 val, mux;
 			int shift;

 			prg->chan[prg_chan].used_pre = i;

 			/* configure the PRE to PRG channel mux */
 			shift = (i == 1) ? 12 : 14;
 			mux = (prg->id << 1) | (prg_chan - 1);
 			regmap_update_bits(prg->iomuxc_gpr, IOMUXC_GPR5,
 					   0x3 << shift, mux << shift);

 			/* check other mux, must not point to same channel */
 			shift = (i == 1) ? 14 : 12;
 			regmap_read(prg->iomuxc_gpr, IOMUXC_GPR5, &val);
 			if (((val >> shift) & 0x3) == mux) {
 				regmap_update_bits(prg->iomuxc_gpr, IOMUXC_GPR5,
 						   0x3 << shift,
 						   (mux ^ 0x1) << shift);
 			}

 			return 0;
 		}
 	}

 fail:
 	dev_err(prg->dev, "could not get PRE for PRG chan %d", prg_chan);
 	return ret;
 }

 static void ipu_prg_put_pre(struct ipu_prg *prg, int prg_chan)
 {
 	struct ipu_prg_channel *chan = &prg->chan[prg_chan];

 	ipu_pre_put(prg->pres[chan->used_pre]);
 	chan->used_pre = -1;
 }

 void ipu_prg_channel_disable(struct ipuv3_channel *ipu_chan)
 {
 	int prg_chan = ipu_prg_ipu_to_prg_chan(ipu_chan->num);
 	struct ipu_prg *prg = ipu_chan->ipu->prg_priv;
 	struct ipu_prg_channel *chan;
 	u32 val;

 	if (prg_chan < 0)
 		return;

 	chan = &prg->chan[prg_chan];
 	if (!chan->enabled)
 		return;

 	pm_runtime_get_sync(prg->dev);

 	val = readl(prg->regs + IPU_PRG_CTL);
 	val |= IPU_PRG_CTL_BYPASS(prg_chan);
 	writel(val, prg->regs + IPU_PRG_CTL);

 	val = IPU_PRG_REG_UPDATE_REG_UPDATE;
 	writel(val, prg->regs + IPU_PRG_REG_UPDATE);

 	pm_runtime_put(prg->dev);

 	ipu_prg_put_pre(prg, prg_chan);

 	chan->enabled = false;
 }
 EXPORT_SYMBOL_GPL(ipu_prg_channel_disable);

 int ipu_prg_channel_configure(struct ipuv3_channel *ipu_chan,
 			      unsigned int axi_id, unsigned int width,
 			      unsigned int height, unsigned int stride,
 			      u32 format, uint64_t modifier, unsigned long *eba)
 {
 	int prg_chan = ipu_prg_ipu_to_prg_chan(ipu_chan->num);
 	struct ipu_prg *prg = ipu_chan->ipu->prg_priv;
 	struct ipu_prg_channel *chan;
 	u32 val;
 	int ret;

 	if (prg_chan < 0)
 		return prg_chan;

 	chan = &prg->chan[prg_chan];

 	if (chan->enabled) {
 		ipu_pre_update(prg->pres[chan->used_pre], *eba);
 		return 0;
 	}

 	ret = ipu_prg_get_pre(prg, prg_chan);
 	if (ret)
 		return ret;

 	ipu_pre_configure(prg->pres[chan->used_pre],
 			  width, height, stride, format, modifier, *eba);


 	pm_runtime_get_sync(prg->dev);

 	val = (stride - 1) & IPU_PRG_STRIDE_STRIDE_MASK;
 	writel(val, prg->regs + IPU_PRG_STRIDE(prg_chan));

 	val = ((height & IPU_PRG_HEIGHT_PRE_HEIGHT_MASK) <<
 	       IPU_PRG_HEIGHT_PRE_HEIGHT_SHIFT) |
 	      ((height & IPU_PRG_HEIGHT_IPU_HEIGHT_MASK) <<
 	       IPU_PRG_HEIGHT_IPU_HEIGHT_SHIFT);
 	writel(val, prg->regs + IPU_PRG_HEIGHT(prg_chan));

 	val = ipu_pre_get_baddr(prg->pres[chan->used_pre]);
 	*eba = val;
 	writel(val, prg->regs + IPU_PRG_BADDR(prg_chan));

 	val = readl(prg->regs + IPU_PRG_CTL);
 	/* config AXI ID */
 	val &= ~(IPU_PRG_CTL_SOFT_ARID_MASK <<
 		 IPU_PRG_CTL_SOFT_ARID_SHIFT(prg_chan));
 	val |= IPU_PRG_CTL_SOFT_ARID(prg_chan, axi_id);
 	/* enable channel */
 	val &= ~IPU_PRG_CTL_BYPASS(prg_chan);
 	writel(val, prg->regs + IPU_PRG_CTL);

 	val = IPU_PRG_REG_UPDATE_REG_UPDATE;
 	writel(val, prg->regs + IPU_PRG_REG_UPDATE);

 	/* wait for both double buffers to be filled */
 	readl_poll_timeout(prg->regs + IPU_PRG_STATUS, val,
 			   (val & IPU_PRG_STATUS_BUFFER0_READY(prg_chan)) &&
 			   (val & IPU_PRG_STATUS_BUFFER1_READY(prg_chan)),
 			   5, 1000);

 	pm_runtime_put(prg->dev);

 	chan->enabled = true;
 	return 0;
 }
 EXPORT_SYMBOL_GPL(ipu_prg_channel_configure);

 static int ipu_prg_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct resource *res;
 	struct ipu_prg *prg;
 	u32 val;
 	int i, ret;

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

 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	prg->regs = devm_ioremap_resource(&pdev->dev, res);
 	if (IS_ERR(prg->regs))
 		return PTR_ERR(prg->regs);


 	prg->clk_ipg = devm_clk_get(dev, "ipg");
 	if (IS_ERR(prg->clk_ipg))
 		return PTR_ERR(prg->clk_ipg);

 	prg->clk_axi = devm_clk_get(dev, "axi");
 	if (IS_ERR(prg->clk_axi))
 		return PTR_ERR(prg->clk_axi);

 	prg->iomuxc_gpr =
 		syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr");
 	if (IS_ERR(prg->iomuxc_gpr))
 		return PTR_ERR(prg->iomuxc_gpr);

 	for (i = 0; i < 3; i++) {
 		prg->pres[i] = ipu_pre_lookup_by_phandle(dev, "fsl,pres", i);
 		if (!prg->pres[i])
 			return -EPROBE_DEFER;
 	}

 	ret = clk_prepare_enable(prg->clk_ipg);
 	if (ret)
 		return ret;

 	ret = clk_prepare_enable(prg->clk_axi);
 	if (ret) {
 		clk_disable_unprepare(prg->clk_ipg);
 		return ret;
 	}

 	/* init to free running mode */
 	val = readl(prg->regs + IPU_PRG_CTL);
 	val |= IPU_PRG_CTL_SHADOW_EN;
 	writel(val, prg->regs + IPU_PRG_CTL);

 	/* disable address threshold */
 	writel(0xffffffff, prg->regs + IPU_PRG_THD);

 	pm_runtime_set_active(dev);
 	pm_runtime_enable(dev);

 	prg->dev = dev;
 	platform_set_drvdata(pdev, prg);
 	mutex_lock(&ipu_prg_list_mutex);
 	list_add(&prg->list, &ipu_prg_list);
 	mutex_unlock(&ipu_prg_list_mutex);

 	return 0;
 }

 static int ipu_prg_remove(struct platform_device *pdev)
 {
 	struct ipu_prg *prg = platform_get_drvdata(pdev);

 	mutex_lock(&ipu_prg_list_mutex);
 	list_del(&prg->list);
 	mutex_unlock(&ipu_prg_list_mutex);

 	return 0;
 }

 #ifdef CONFIG_PM
 static int prg_suspend(struct device *dev)
 {
 	struct ipu_prg *prg = dev_get_drvdata(dev);

 	clk_disable_unprepare(prg->clk_axi);
 	clk_disable_unprepare(prg->clk_ipg);

 	return 0;
 }

 static int prg_resume(struct device *dev)
 {
 	struct ipu_prg *prg = dev_get_drvdata(dev);
 	int ret;

 	ret = clk_prepare_enable(prg->clk_ipg);
 	if (ret)
 		return ret;

 	ret = clk_prepare_enable(prg->clk_axi);
 	if (ret) {
 		clk_disable_unprepare(prg->clk_ipg);
 		return ret;
 	}

 	return 0;
 }
 #endif

 static const struct dev_pm_ops prg_pm_ops = {
 	SET_RUNTIME_PM_OPS(prg_suspend, prg_resume, NULL)
 };

 static const struct of_device_id ipu_prg_dt_ids[] = {
 	{ .compatible = "fsl,imx6qp-prg", },
 	{ /* sentinel */ },
 };

 struct platform_driver ipu_prg_drv = {
 	.probe		= ipu_prg_probe,
 	.remove		= ipu_prg_remove,
 	.driver		= {
 		.name	= "imx-ipu-prg",
 		.pm	= &prg_pm_ops,
 		.of_match_table = ipu_prg_dt_ids,
 	},
 };
	/*
	* Copyright (c) 2016-2017 Lucas Stach, Pengutronix
	*
	* This program is free software; you can redistribute it and/or modify it
	* under the terms and conditions of the GNU General Public License,
	* version 2, as published by the Free Software Foundation.
	*
	* This program is distributed in the hope it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	* more details.
	*/

	#include <drm/drm_fourcc.h>
	#include <linux/clk.h>
	#include <linux/err.h>
	#include <linux/iopoll.h>
	#include <linux/mfd/syscon.h>
	#include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
	#include <linux/module.h>
	#include <linux/of.h>
	#include <linux/platform_device.h>
	#include <linux/pm_runtime.h>
	#include <linux/regmap.h>
	#include <video/imx-ipu-v3.h>

	#include "ipu-prv.h"

	#define IPU_PRG_CTL 0x00
	#define IPU_PRG_CTL_BYPASS(i) (1 << (0 + i))
	#define IPU_PRG_CTL_SOFT_ARID_MASK 0x3
	#define IPU_PRG_CTL_SOFT_ARID_SHIFT(i) (8 + i * 2)
	#define IPU_PRG_CTL_SOFT_ARID(i, v) ((v & 0x3) << (8 + 2 * i))
	#define IPU_PRG_CTL_SO(i) (1 << (16 + i))
	#define IPU_PRG_CTL_VFLIP(i) (1 << (19 + i))
	#define IPU_PRG_CTL_BLOCK_MODE(i) (1 << (22 + i))
	#define IPU_PRG_CTL_CNT_LOAD_EN(i) (1 << (25 + i))
	#define IPU_PRG_CTL_SOFTRST (1 << 30)
	#define IPU_PRG_CTL_SHADOW_EN (1 << 31)

	#define IPU_PRG_STATUS 0x04
	#define IPU_PRG_STATUS_BUFFER0_READY(i) (1 << (0 + i * 2))
	#define IPU_PRG_STATUS_BUFFER1_READY(i) (1 << (1 + i * 2))

	#define IPU_PRG_QOS 0x08
	#define IPU_PRG_QOS_ARID_MASK 0xf
	#define IPU_PRG_QOS_ARID_SHIFT(i) (0 + i * 4)

	#define IPU_PRG_REG_UPDATE 0x0c
	#define IPU_PRG_REG_UPDATE_REG_UPDATE (1 << 0)

	#define IPU_PRG_STRIDE(i) (0x10 + i * 0x4)
	#define IPU_PRG_STRIDE_STRIDE_MASK 0x3fff

	#define IPU_PRG_CROP_LINE 0x1c

	#define IPU_PRG_THD 0x20

	#define IPU_PRG_BADDR(i) (0x24 + i * 0x4)

	#define IPU_PRG_OFFSET(i) (0x30 + i * 0x4)

	#define IPU_PRG_ILO(i) (0x3c + i * 0x4)

	#define IPU_PRG_HEIGHT(i) (0x48 + i * 0x4)
	#define IPU_PRG_HEIGHT_PRE_HEIGHT_MASK 0xfff
	#define IPU_PRG_HEIGHT_PRE_HEIGHT_SHIFT 0
	#define IPU_PRG_HEIGHT_IPU_HEIGHT_MASK 0xfff
	#define IPU_PRG_HEIGHT_IPU_HEIGHT_SHIFT 16

	struct ipu_prg_channel {
	bool enabled;
	int used_pre;
	};

	struct ipu_prg {
	struct list_head list;
	struct device *dev;
	int id;

	void __iomem *regs;
	struct clk clk_ipg, clk_axi;
	struct regmap *iomuxc_gpr;
	struct ipu_pre *pres[3];

	struct ipu_prg_channel chan[3];
	};

	static DEFINE_MUTEX(ipu_prg_list_mutex);
	static LIST_HEAD(ipu_prg_list);

	struct ipu_prg *
	ipu_prg_lookup_by_phandle(struct device dev, const char name, int ipu_id)
	{
	struct device_node *prg_node = of_parse_phandle(dev->of_node,
	name, 0);
	struct ipu_prg *prg;

	mutex_lock(&ipu_prg_list_mutex);
	list_for_each_entry(prg, &ipu_prg_list, list) {
	if (prg_node == prg->dev->of_node) {
	mutex_unlock(&ipu_prg_list_mutex);
	device_link_add(dev, prg->dev,
	DL_FLAG_AUTOREMOVE_CONSUMER);
	prg->id = ipu_id;
	of_node_put(prg_node);
	return prg;
	}
	}
	mutex_unlock(&ipu_prg_list_mutex);

	of_node_put(prg_node);

	return NULL;
	}

	int ipu_prg_max_active_channels(void)
	{
	return ipu_pre_get_available_count();
	}
	EXPORT_SYMBOL_GPL(ipu_prg_max_active_channels);

	bool ipu_prg_present(struct ipu_soc *ipu)
	{
	if (ipu->prg_priv)
	return true;

	return false;
	}
	EXPORT_SYMBOL_GPL(ipu_prg_present);

	bool ipu_prg_format_supported(struct ipu_soc *ipu, uint32_t format,
	uint64_t modifier)
	{
	const struct drm_format_info *info = drm_format_info(format);

	if (info->num_planes != 1)
	return false;

	switch (modifier) {
	case DRM_FORMAT_MOD_LINEAR:
	case DRM_FORMAT_MOD_VIVANTE_TILED:
	case DRM_FORMAT_MOD_VIVANTE_SUPER_TILED:
	return true;
	default:
	return false;
	}
	}
	EXPORT_SYMBOL_GPL(ipu_prg_format_supported);

	int ipu_prg_enable(struct ipu_soc *ipu)
	{
	struct ipu_prg *prg = ipu->prg_priv;

	if (!prg)
	return 0;

	return pm_runtime_get_sync(prg->dev);
	}
	EXPORT_SYMBOL_GPL(ipu_prg_enable);

	void ipu_prg_disable(struct ipu_soc *ipu)
	{
	struct ipu_prg *prg = ipu->prg_priv;

	if (!prg)
	return;

	pm_runtime_put(prg->dev);
	}
	EXPORT_SYMBOL_GPL(ipu_prg_disable);

	/*
	* The channel configuartion functions below are not thread safe, as they
	* must be only called from the atomic commit path in the DRM driver, which
	* is properly serialized.
	*/
	static int ipu_prg_ipu_to_prg_chan(int ipu_chan)
	{
	/*
	* This isn't clearly documented in the RM, but IPU to PRG channel
	* assignment is fixed, as only with this mapping the control signals
	* match up.
	*/
	switch (ipu_chan) {
	case IPUV3_CHANNEL_MEM_BG_SYNC:
	return 0;
	case IPUV3_CHANNEL_MEM_FG_SYNC:
	return 1;
	case IPUV3_CHANNEL_MEM_DC_SYNC:
	return 2;
	default:
	return -EINVAL;
	}
	}

	static int ipu_prg_get_pre(struct ipu_prg *prg, int prg_chan)
	{
	int i, ret;

	/* channel 0 is special as it is hardwired to one of the PREs */
	if (prg_chan == 0) {
	ret = ipu_pre_get(prg->pres[0]);
	if (ret)
	goto fail;
	prg->chan[prg_chan].used_pre = 0;
	return 0;
	}

	for (i = 1; i < 3; i++) {
	ret = ipu_pre_get(prg->pres[i]);
	if (!ret) {
	u32 val, mux;
	int shift;

	prg->chan[prg_chan].used_pre = i;

	/* configure the PRE to PRG channel mux */
	shift = (i == 1) ? 12 : 14;
	mux = (prg->id << 1) \| (prg_chan - 1);
	regmap_update_bits(prg->iomuxc_gpr, IOMUXC_GPR5,
	0x3 << shift, mux << shift);

	/* check other mux, must not point to same channel */
	shift = (i == 1) ? 14 : 12;
	regmap_read(prg->iomuxc_gpr, IOMUXC_GPR5, &val);
	if (((val >> shift) & 0x3) == mux) {
	regmap_update_bits(prg->iomuxc_gpr, IOMUXC_GPR5,
	0x3 << shift,
	(mux ^ 0x1) << shift);
	}

	return 0;
	}
	}

	fail:
	dev_err(prg->dev, "could not get PRE for PRG chan %d", prg_chan);
	return ret;
	}

	static void ipu_prg_put_pre(struct ipu_prg *prg, int prg_chan)
	{
	struct ipu_prg_channel *chan = &prg->chan[prg_chan];

	ipu_pre_put(prg->pres[chan->used_pre]);
	chan->used_pre = -1;
	}

	void ipu_prg_channel_disable(struct ipuv3_channel *ipu_chan)
	{
	int prg_chan = ipu_prg_ipu_to_prg_chan(ipu_chan->num);
	struct ipu_prg *prg = ipu_chan->ipu->prg_priv;
	struct ipu_prg_channel *chan;
	u32 val;

	if (prg_chan < 0)
	return;

	chan = &prg->chan[prg_chan];
	if (!chan->enabled)
	return;

	pm_runtime_get_sync(prg->dev);

	val = readl(prg->regs + IPU_PRG_CTL);
	val \|= IPU_PRG_CTL_BYPASS(prg_chan);
	writel(val, prg->regs + IPU_PRG_CTL);

	val = IPU_PRG_REG_UPDATE_REG_UPDATE;
	writel(val, prg->regs + IPU_PRG_REG_UPDATE);

	pm_runtime_put(prg->dev);

	ipu_prg_put_pre(prg, prg_chan);

	chan->enabled = false;
	}
	EXPORT_SYMBOL_GPL(ipu_prg_channel_disable);

	int ipu_prg_channel_configure(struct ipuv3_channel *ipu_chan,
	unsigned int axi_id, unsigned int width,
	unsigned int height, unsigned int stride,
	u32 format, uint64_t modifier, unsigned long *eba)
	{
	int prg_chan = ipu_prg_ipu_to_prg_chan(ipu_chan->num);
	struct ipu_prg *prg = ipu_chan->ipu->prg_priv;
	struct ipu_prg_channel *chan;
	u32 val;
	int ret;

	if (prg_chan < 0)
	return prg_chan;

	chan = &prg->chan[prg_chan];

	if (chan->enabled) {
	ipu_pre_update(prg->pres[chan->used_pre], *eba);
	return 0;
	}

	ret = ipu_prg_get_pre(prg, prg_chan);
	if (ret)
	return ret;

	ipu_pre_configure(prg->pres[chan->used_pre],
	width, height, stride, format, modifier, *eba);


	pm_runtime_get_sync(prg->dev);

	val = (stride - 1) & IPU_PRG_STRIDE_STRIDE_MASK;
	writel(val, prg->regs + IPU_PRG_STRIDE(prg_chan));

	val = ((height & IPU_PRG_HEIGHT_PRE_HEIGHT_MASK) <<
	IPU_PRG_HEIGHT_PRE_HEIGHT_SHIFT) \|
	((height & IPU_PRG_HEIGHT_IPU_HEIGHT_MASK) <<
	IPU_PRG_HEIGHT_IPU_HEIGHT_SHIFT);
	writel(val, prg->regs + IPU_PRG_HEIGHT(prg_chan));

	val = ipu_pre_get_baddr(prg->pres[chan->used_pre]);
	*eba = val;
	writel(val, prg->regs + IPU_PRG_BADDR(prg_chan));

	val = readl(prg->regs + IPU_PRG_CTL);
	/* config AXI ID */
	val &= ~(IPU_PRG_CTL_SOFT_ARID_MASK <<
	IPU_PRG_CTL_SOFT_ARID_SHIFT(prg_chan));
	val \|= IPU_PRG_CTL_SOFT_ARID(prg_chan, axi_id);
	/* enable channel */
	val &= ~IPU_PRG_CTL_BYPASS(prg_chan);
	writel(val, prg->regs + IPU_PRG_CTL);

	val = IPU_PRG_REG_UPDATE_REG_UPDATE;
	writel(val, prg->regs + IPU_PRG_REG_UPDATE);

	/* wait for both double buffers to be filled */
	readl_poll_timeout(prg->regs + IPU_PRG_STATUS, val,
	(val & IPU_PRG_STATUS_BUFFER0_READY(prg_chan)) &&
	(val & IPU_PRG_STATUS_BUFFER1_READY(prg_chan)),
	5, 1000);

	pm_runtime_put(prg->dev);

	chan->enabled = true;
	return 0;
	}
	EXPORT_SYMBOL_GPL(ipu_prg_channel_configure);

	static int ipu_prg_probe(struct platform_device *pdev)
	{
	struct device *dev = &pdev->dev;
	struct resource *res;
	struct ipu_prg *prg;
	u32 val;
	int i, ret;

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

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	prg->regs = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(prg->regs))
	return PTR_ERR(prg->regs);


	prg->clk_ipg = devm_clk_get(dev, "ipg");
	if (IS_ERR(prg->clk_ipg))
	return PTR_ERR(prg->clk_ipg);

	prg->clk_axi = devm_clk_get(dev, "axi");
	if (IS_ERR(prg->clk_axi))
	return PTR_ERR(prg->clk_axi);

	prg->iomuxc_gpr =
	syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr");
	if (IS_ERR(prg->iomuxc_gpr))
	return PTR_ERR(prg->iomuxc_gpr);

	for (i = 0; i < 3; i++) {
	prg->pres[i] = ipu_pre_lookup_by_phandle(dev, "fsl,pres", i);
	if (!prg->pres[i])
	return -EPROBE_DEFER;
	}

	ret = clk_prepare_enable(prg->clk_ipg);
	if (ret)
	return ret;

	ret = clk_prepare_enable(prg->clk_axi);
	if (ret) {
	clk_disable_unprepare(prg->clk_ipg);
	return ret;
	}

	/* init to free running mode */
	val = readl(prg->regs + IPU_PRG_CTL);
	val \|= IPU_PRG_CTL_SHADOW_EN;
	writel(val, prg->regs + IPU_PRG_CTL);

	/* disable address threshold */
	writel(0xffffffff, prg->regs + IPU_PRG_THD);

	pm_runtime_set_active(dev);
	pm_runtime_enable(dev);

	prg->dev = dev;
	platform_set_drvdata(pdev, prg);
	mutex_lock(&ipu_prg_list_mutex);
	list_add(&prg->list, &ipu_prg_list);
	mutex_unlock(&ipu_prg_list_mutex);

	return 0;
	}

	static int ipu_prg_remove(struct platform_device *pdev)
	{
	struct ipu_prg *prg = platform_get_drvdata(pdev);

	mutex_lock(&ipu_prg_list_mutex);
	list_del(&prg->list);
	mutex_unlock(&ipu_prg_list_mutex);

	return 0;
	}

	#ifdef CONFIG_PM
	static int prg_suspend(struct device *dev)
	{
	struct ipu_prg *prg = dev_get_drvdata(dev);

	clk_disable_unprepare(prg->clk_axi);
	clk_disable_unprepare(prg->clk_ipg);

	return 0;
	}

	static int prg_resume(struct device *dev)
	{
	struct ipu_prg *prg = dev_get_drvdata(dev);
	int ret;

	ret = clk_prepare_enable(prg->clk_ipg);
	if (ret)
	return ret;

	ret = clk_prepare_enable(prg->clk_axi);
	if (ret) {
	clk_disable_unprepare(prg->clk_ipg);
	return ret;
	}

	return 0;
	}
	#endif

	static const struct dev_pm_ops prg_pm_ops = {
	SET_RUNTIME_PM_OPS(prg_suspend, prg_resume, NULL)
	};

	static const struct of_device_id ipu_prg_dt_ids[] = {
	{ .compatible = "fsl,imx6qp-prg", },
	{ /* sentinel */ },
	};

	struct platform_driver ipu_prg_drv = {
	.probe = ipu_prg_probe,
	.remove = ipu_prg_remove,
	.driver = {
	.name = "imx-ipu-prg",
	.pm = &prg_pm_ops,
	.of_match_table = ipu_prg_dt_ids,
	},
	};