From ea9c260514c15f14d43a4c099646c44238dccf1e Mon Sep 17 00:00:00 2001
From: Lucas Stach <l.stach@pengutronix.de>
Date: Wed, 8 Mar 2017 12:13:16 +0100
Subject: [PATCH] gpu: ipu-v3: add driver for Prefetch Resolve Gasket

This adds support for the i.MX6 QUadPlus PRG unit. It glues together the
IPU and the PRE units.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
---
v4: add missing ipu_soc->prg_priv
---
 drivers/gpu/ipu-v3/Makefile     |   2 +-
 drivers/gpu/ipu-v3/ipu-common.c |   1 +
 drivers/gpu/ipu-v3/ipu-prg.c    | 424 ++++++++++++++++++++++++++++++++
 drivers/gpu/ipu-v3/ipu-prv.h    |   6 +
 include/video/imx-ipu-v3.h      |  15 ++
 5 files changed, 447 insertions(+), 1 deletion(-)
 create mode 100644 drivers/gpu/ipu-v3/ipu-prg.c

diff --git a/drivers/gpu/ipu-v3/Makefile b/drivers/gpu/ipu-v3/Makefile
index 8ae90de46b4d..1ab9bceee755 100644
--- a/drivers/gpu/ipu-v3/Makefile
+++ b/drivers/gpu/ipu-v3/Makefile
@@ -2,4 +2,4 @@ obj-$(CONFIG_IMX_IPUV3_CORE) += imx-ipu-v3.o
 
 imx-ipu-v3-objs := ipu-common.o ipu-cpmem.o ipu-csi.o ipu-dc.o ipu-di.o \
 		ipu-dp.o ipu-dmfc.o ipu-ic.o ipu-image-convert.o \
-		ipu-pre.o ipu-smfc.o ipu-vdi.o
+		ipu-pre.o ipu-prg.o ipu-smfc.o ipu-vdi.o
diff --git a/drivers/gpu/ipu-v3/ipu-common.c b/drivers/gpu/ipu-v3/ipu-common.c
index 7ae1b9739a7f..4c8453989746 100644
--- a/drivers/gpu/ipu-v3/ipu-common.c
+++ b/drivers/gpu/ipu-v3/ipu-common.c
@@ -1530,6 +1530,7 @@ static struct platform_driver imx_ipu_driver = {
 
 static struct platform_driver * const drivers[] = {
 	&ipu_pre_drv,
+	&ipu_prg_drv,
 	&imx_ipu_driver,
 };
 
diff --git a/drivers/gpu/ipu-v3/ipu-prg.c b/drivers/gpu/ipu-v3/ipu-prg.c
new file mode 100644
index 000000000000..caca57febbd6
--- /dev/null
+++ b/drivers/gpu/ipu-v3/ipu-prg.c
@@ -0,0 +1,424 @@
+/*
+ * 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/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/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);
+			prg->id = ipu_id;
+			return prg;
+		}
+	}
+	mutex_unlock(&ipu_prg_list_mutex);
+
+	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;
+
+	return true;
+}
+EXPORT_SYMBOL_GPL(ipu_prg_format_supported);
+
+int ipu_prg_enable(struct ipu_soc *ipu)
+{
+	struct ipu_prg *prg = ipu->prg_priv;
+	int ret;
+
+	if (!prg)
+		return 0;
+
+	ret = clk_prepare_enable(prg->clk_axi);
+	if (ret)
+		goto fail_disable_ipg;
+
+	return 0;
+
+fail_disable_ipg:
+	clk_disable_unprepare(prg->clk_ipg);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(ipu_prg_enable);
+
+void ipu_prg_disable(struct ipu_soc *ipu)
+{
+	struct ipu_prg *prg = ipu->prg_priv;
+
+	if (!prg)
+		return;
+
+	clk_disable_unprepare(prg->clk_axi);
+}
+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 = &prg->chan[prg_chan];
+	u32 val;
+
+	if (!chan->enabled || prg_chan < 0)
+		return;
+
+	clk_prepare_enable(prg->clk_ipg);
+
+	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);
+
+	clk_disable_unprepare(prg->clk_ipg);
+
+	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, 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 = &prg->chan[prg_chan];
+	u32 val;
+	int ret;
+
+	if (prg_chan < 0)
+		return 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, *eba);
+
+
+	ret = clk_prepare_enable(prg->clk_ipg);
+	if (ret) {
+		ipu_prg_put_pre(prg, prg_chan);
+		return ret;
+	}
+
+	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);
+	/* counter load enable */
+	val |= IPU_PRG_CTL_CNT_LOAD_EN(prg_chan);
+	/* 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);
+
+	clk_disable_unprepare(prg->clk_ipg);
+
+	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;
+
+	/* 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);
+
+	clk_disable_unprepare(prg->clk_ipg);
+
+	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;
+}
+
+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",
+		.of_match_table = ipu_prg_dt_ids,
+	},
+};
diff --git a/drivers/gpu/ipu-v3/ipu-prv.h b/drivers/gpu/ipu-v3/ipu-prv.h
index 262efdff1dba..ca2a223a0d1e 100644
--- a/drivers/gpu/ipu-v3/ipu-prv.h
+++ b/drivers/gpu/ipu-v3/ipu-prv.h
@@ -174,6 +174,7 @@ struct ipu_vdi;
 struct ipu_image_convert_priv;
 struct ipu_smfc_priv;
 struct ipu_pre;
+struct ipu_prg;
 
 struct ipu_devtype;
 
@@ -208,6 +209,7 @@ struct ipu_soc {
 	struct ipu_vdi          *vdi_priv;
 	struct ipu_image_convert_priv *image_convert_priv;
 	struct ipu_smfc_priv	*smfc_priv;
+	struct ipu_prg		*prg_priv;
 };
 
 static inline u32 ipu_idmac_read(struct ipu_soc *ipu, unsigned offset)
@@ -276,6 +278,10 @@ void ipu_pre_configure(struct ipu_pre *pre, unsigned int width,
 		       unsigned int stride, u32 format, unsigned int bufaddr);
 void ipu_pre_update(struct ipu_pre *pre, unsigned int bufaddr);
 
+struct ipu_prg *ipu_prg_lookup_by_phandle(struct device *dev, const char *name,
+					  int ipu_id);
+
 extern struct platform_driver ipu_pre_drv;
+extern struct platform_driver ipu_prg_drv;
 
 #endif				/* __IPU_PRV_H__ */
diff --git a/include/video/imx-ipu-v3.h b/include/video/imx-ipu-v3.h
index 6af74f0cf161..8cb07680fb41 100644
--- a/include/video/imx-ipu-v3.h
+++ b/include/video/imx-ipu-v3.h
@@ -330,6 +330,21 @@ int ipu_dp_set_window_pos(struct ipu_dp *, u16 x_pos, u16 y_pos);
 int ipu_dp_set_global_alpha(struct ipu_dp *dp, bool enable, u8 alpha,
 		bool bg_chan);
 
+/*
+ * IPU Prefetch Resolve Gasket (prg) functions
+ */
+int ipu_prg_max_active_channels(void);
+bool ipu_prg_present(struct ipu_soc *ipu);
+bool ipu_prg_format_supported(struct ipu_soc *ipu, uint32_t format,
+			      uint64_t modifier);
+int ipu_prg_enable(struct ipu_soc *ipu);
+void ipu_prg_disable(struct ipu_soc *ipu);
+void ipu_prg_channel_disable(struct ipuv3_channel *ipu_chan);
+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, unsigned long *eba);
+
 /*
  * IPU CMOS Sensor Interface (csi) functions
  */
-- 
2.20.1