[v8,02/11] drm: sti: add VTG driver

diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
index f512004..31894c8 100644
--- a/drivers/gpu/drm/Kconfig
+++ b/drivers/gpu/drm/Kconfig
@@ -201,3 +201,5 @@  source "drivers/gpu/drm/msm/Kconfig"
 source "drivers/gpu/drm/tegra/Kconfig"
 
 source "drivers/gpu/drm/panel/Kconfig"
+
+source "drivers/gpu/drm/sti/Kconfig"
diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
index 61d9e9c..60eb5d4 100644
--- a/drivers/gpu/drm/Makefile
+++ b/drivers/gpu/drm/Makefile
@@ -64,6 +64,7 @@  obj-$(CONFIG_DRM_QXL) += qxl/
 obj-$(CONFIG_DRM_BOCHS) += bochs/
 obj-$(CONFIG_DRM_MSM) += msm/
 obj-$(CONFIG_DRM_TEGRA) += tegra/
+obj-$(CONFIG_DRM_STI) += sti/
 obj-y			+= i2c/
 obj-y			+= panel/
 obj-y			+= bridge/
diff --git a/drivers/gpu/drm/sti/Kconfig b/drivers/gpu/drm/sti/Kconfig
new file mode 100644
index 0000000..a18df02
--- /dev/null
+++ b/drivers/gpu/drm/sti/Kconfig
@@ -0,0 +1,5 @@ 
+config DRM_STI
+	tristate "DRM Support for STMicroelectronics SoC stiH41x Series"
+	depends on DRM && (SOC_STIH415 || SOC_STIH416 || ARCH_MULTIPLATFORM)
+	help
+	  Choose this option to enable DRM on STM stiH41x chipset
diff --git a/drivers/gpu/drm/sti/Makefile b/drivers/gpu/drm/sti/Makefile
new file mode 100644
index 0000000..1759c20
--- /dev/null
+++ b/drivers/gpu/drm/sti/Makefile
@@ -0,0 +1,2 @@ 
+obj-$(CONFIG_DRM_STI) = \
+	sti_vtg.o
diff --git a/drivers/gpu/drm/sti/sti_vtg.c b/drivers/gpu/drm/sti/sti_vtg.c
new file mode 100644
index 0000000..740d6e3
--- /dev/null
+++ b/drivers/gpu/drm/sti/sti_vtg.c
@@ -0,0 +1,366 @@ 
+/*
+ * Copyright (C) STMicroelectronics SA 2014
+ * Authors: Benjamin Gaignard <benjamin.gaignard@st.com>
+ *          Fabien Dessenne <fabien.dessenne@st.com>
+ *          Vincent Abriou <vincent.abriou@st.com>
+ *          for STMicroelectronics.
+ * License terms:  GNU General Public License (GPL), version 2
+ */
+
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/platform_device.h>
+
+#include <drm/drmP.h>
+
+#include "sti_vtg.h"
+
+#define VTG_TYPE_MASTER         0
+#define VTG_TYPE_SLAVE_BY_EXT0  1
+
+/* registers offset */
+#define VTG_MODE            0x0000
+#define VTG_CLKLN           0x0008
+#define VTG_HLFLN           0x000C
+#define VTG_DRST_AUTOC      0x0010
+#define VTG_VID_TFO         0x0040
+#define VTG_VID_TFS         0x0044
+#define VTG_VID_BFO         0x0048
+#define VTG_VID_BFS         0x004C
+
+#define VTG_HOST_ITS        0x0078
+#define VTG_HOST_ITS_BCLR   0x007C
+#define VTG_HOST_ITM_BCLR   0x0088
+#define VTG_HOST_ITM_BSET   0x008C
+
+#define VTG_H_HD_1          0x00C0
+#define VTG_TOP_V_VD_1      0x00C4
+#define VTG_BOT_V_VD_1      0x00C8
+#define VTG_TOP_V_HD_1      0x00CC
+#define VTG_BOT_V_HD_1      0x00D0
+
+#define VTG_H_HD_2          0x00E0
+#define VTG_TOP_V_VD_2      0x00E4
+#define VTG_BOT_V_VD_2      0x00E8
+#define VTG_TOP_V_HD_2      0x00EC
+#define VTG_BOT_V_HD_2      0x00F0
+
+#define VTG_H_HD_3          0x0100
+#define VTG_TOP_V_VD_3      0x0104
+#define VTG_BOT_V_VD_3      0x0108
+#define VTG_TOP_V_HD_3      0x010C
+#define VTG_BOT_V_HD_3      0x0110
+
+#define VTG_IRQ_BOTTOM      BIT(0)
+#define VTG_IRQ_TOP         BIT(1)
+#define VTG_IRQ_MASK        (VTG_IRQ_TOP | VTG_IRQ_BOTTOM)
+
+/* delay introduced by the Arbitrary Waveform Generator in nb of pixels */
+#define AWG_DELAY_HD        (-9)
+#define AWG_DELAY_ED        (-8)
+#define AWG_DELAY_SD        (-7)
+
+LIST_HEAD(vtg_lookup);
+
+/**
+ * STI VTG structure
+ *
+ * @dev: pointer to device driver
+ * @data: data associated to the device
+ * @irq: VTG irq
+ * @type: VTG type (main or aux)
+ * @notifier_list: notifier callback
+ * @crtc_id: the crtc id for vblank event
+ * @slave: slave vtg
+ * @link: List node to link the structure in lookup list
+ */
+struct sti_vtg {
+	struct device *dev;
+	struct device_node *np;
+	void __iomem *regs;
+	int irq;
+	u32 irq_status;
+	struct raw_notifier_head notifier_list;
+	int crtc_id;
+	struct sti_vtg *slave;
+	struct list_head link;
+};
+
+static void vtg_register(struct sti_vtg *vtg)
+{
+	list_add_tail(&vtg->link, &vtg_lookup);
+}
+
+struct sti_vtg *of_vtg_find(struct device_node *np)
+{
+	struct sti_vtg *vtg;
+
+	list_for_each_entry(vtg, &vtg_lookup, link) {
+		if (vtg->np == np)
+			return vtg;
+	}
+	return NULL;
+}
+EXPORT_SYMBOL(of_vtg_find);
+
+static void vtg_reset(struct sti_vtg *vtg)
+{
+	/* reset slave and then master */
+	if (vtg->slave)
+		vtg_reset(vtg->slave);
+
+	writel(1, vtg->regs + VTG_DRST_AUTOC);
+}
+
+static void vtg_set_mode(struct sti_vtg *vtg,
+			 int type, const struct drm_display_mode *mode)
+{
+	u32 tmp;
+
+	if (vtg->slave)
+		vtg_set_mode(vtg->slave, VTG_TYPE_SLAVE_BY_EXT0, mode);
+
+	writel(mode->htotal, vtg->regs + VTG_CLKLN);
+	writel(mode->vtotal * 2, vtg->regs + VTG_HLFLN);
+
+	tmp = (mode->vtotal - mode->vsync_start + 1) << 16;
+	tmp |= mode->htotal - mode->hsync_start;
+	writel(tmp, vtg->regs + VTG_VID_TFO);
+	writel(tmp, vtg->regs + VTG_VID_BFO);
+
+	tmp = (mode->vdisplay + mode->vtotal - mode->vsync_start + 1) << 16;
+	tmp |= mode->hdisplay + mode->htotal - mode->hsync_start;
+	writel(tmp, vtg->regs + VTG_VID_TFS);
+	writel(tmp, vtg->regs + VTG_VID_BFS);
+
+	/* prepare VTG set 1 and 2 for HDMI and VTG set 3 for HD DAC */
+	tmp = (mode->hsync_end - mode->hsync_start) << 16;
+	writel(tmp, vtg->regs + VTG_H_HD_1);
+	writel(tmp, vtg->regs + VTG_H_HD_2);
+
+	tmp = (mode->vsync_end - mode->vsync_start + 1) << 16;
+	tmp |= 1;
+	writel(tmp, vtg->regs + VTG_TOP_V_VD_1);
+	writel(tmp, vtg->regs + VTG_BOT_V_VD_1);
+	writel(0, vtg->regs + VTG_TOP_V_HD_1);
+	writel(0, vtg->regs + VTG_BOT_V_HD_1);
+
+	/* prepare VTG set 2 for for HD DCS */
+	writel(tmp, vtg->regs + VTG_TOP_V_VD_2);
+	writel(tmp, vtg->regs + VTG_BOT_V_VD_2);
+	writel(0, vtg->regs + VTG_TOP_V_HD_2);
+	writel(0, vtg->regs + VTG_BOT_V_HD_2);
+
+	/* prepare VTG set 3 for HD Analog in HD mode */
+	tmp = (mode->hsync_end - mode->hsync_start + AWG_DELAY_HD) << 16;
+	tmp |= mode->htotal + AWG_DELAY_HD;
+	writel(tmp, vtg->regs + VTG_H_HD_3);
+
+	tmp = (mode->vsync_end - mode->vsync_start) << 16;
+	tmp |= mode->vtotal;
+	writel(tmp, vtg->regs + VTG_TOP_V_VD_3);
+	writel(tmp, vtg->regs + VTG_BOT_V_VD_3);
+
+	tmp = (mode->htotal + AWG_DELAY_HD) << 16;
+	tmp |= mode->htotal + AWG_DELAY_HD;
+	writel(tmp, vtg->regs + VTG_TOP_V_HD_3);
+	writel(tmp, vtg->regs + VTG_BOT_V_HD_3);
+
+	/* mode */
+	writel(type, vtg->regs + VTG_MODE);
+}
+
+static void vtg_enable_irq(struct sti_vtg *vtg)
+{
+	/* clear interrupt status and mask */
+	writel(0xFFFF, vtg->regs + VTG_HOST_ITS_BCLR);
+	writel(0xFFFF, vtg->regs + VTG_HOST_ITM_BCLR);
+	writel(VTG_IRQ_MASK, vtg->regs + VTG_HOST_ITM_BSET);
+}
+
+void sti_vtg_set_config(struct sti_vtg *vtg,
+		const struct drm_display_mode *mode)
+{
+	/* write configuration */
+	vtg_set_mode(vtg, VTG_TYPE_MASTER, mode);
+
+	vtg_reset(vtg);
+
+	/* enable irq for the vtg vblank synchro */
+	if (vtg->slave)
+		vtg_enable_irq(vtg->slave);
+	else
+		vtg_enable_irq(vtg);
+}
+EXPORT_SYMBOL(sti_vtg_set_config);
+
+/**
+ * sti_vtg_get_line_number
+ *
+ * @mode: display mode to be used
+ * @y:    line
+ *
+ * Return the line number according to the display mode taking
+ * into account the Sync and Back Porch information.
+ * Video frame line numbers start at 1, y starts at 0.
+ * In interlaced modes the start line is the field line number of the odd
+ * field, but y is still defined as a progressive frame.
+ */
+u32 sti_vtg_get_line_number(struct drm_display_mode mode, int y)
+{
+	u32 start_line = mode.vtotal - mode.vsync_start + 1;
+
+	if (mode.flags & DRM_MODE_FLAG_INTERLACE)
+		start_line *= 2;
+
+	return start_line + y;
+}
+EXPORT_SYMBOL(sti_vtg_get_line_number);
+
+/**
+ * sti_vtg_get_pixel_number
+ *
+ * @mode: display mode to be used
+ * @x:    row
+ *
+ * Return the pixel number according to the display mode taking
+ * into account the Sync and Back Porch information.
+ * Pixels are counted from 0.
+ */
+u32 sti_vtg_get_pixel_number(struct drm_display_mode mode, int x)
+{
+	return mode.htotal - mode.hsync_start + x;
+}
+EXPORT_SYMBOL(sti_vtg_get_pixel_number);
+
+int sti_vtg_register_client(struct sti_vtg *vtg,
+		struct notifier_block *nb, int crtc_id)
+{
+	if (vtg->slave)
+		return sti_vtg_register_client(vtg->slave, nb, crtc_id);
+
+	vtg->crtc_id = crtc_id;
+	return raw_notifier_chain_register(&vtg->notifier_list, nb);
+}
+EXPORT_SYMBOL(sti_vtg_register_client);
+
+int sti_vtg_unregister_client(struct sti_vtg *vtg, struct notifier_block *nb)
+{
+	if (vtg->slave)
+		return sti_vtg_unregister_client(vtg->slave, nb);
+
+	return raw_notifier_chain_unregister(&vtg->notifier_list, nb);
+}
+EXPORT_SYMBOL(sti_vtg_unregister_client);
+
+static irqreturn_t vtg_irq_thread(int irq, void *arg)
+{
+	struct sti_vtg *vtg = arg;
+	u32 event;
+
+	event = (vtg->irq_status & VTG_IRQ_TOP) ?
+		VTG_TOP_FIELD_EVENT : VTG_BOTTOM_FIELD_EVENT;
+
+	raw_notifier_call_chain(&vtg->notifier_list, event, &vtg->crtc_id);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t vtg_irq(int irq, void *arg)
+{
+	struct sti_vtg *vtg = arg;
+
+	vtg->irq_status = readl(vtg->regs + VTG_HOST_ITS);
+
+	writel(vtg->irq_status, vtg->regs + VTG_HOST_ITS_BCLR);
+
+	/* force sync bus write */
+	readl(vtg->regs + VTG_HOST_ITS);
+
+	return IRQ_WAKE_THREAD;
+}
+
+static int vtg_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np;
+	struct sti_vtg *vtg;
+	struct resource *res;
+	char irq_name[32];
+	int ret;
+
+	vtg = devm_kzalloc(dev, sizeof(*vtg), GFP_KERNEL);
+	if (!vtg)
+		return -ENOMEM;
+
+	vtg->dev = dev;
+	vtg->np = pdev->dev.of_node;
+
+	/* Get Memory ressources */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		DRM_ERROR("Get memory resource failed\n");
+		return -ENOMEM;
+	}
+	vtg->regs = devm_ioremap_nocache(dev, res->start, resource_size(res));
+
+	np = of_parse_phandle(pdev->dev.of_node, "st,slave", 0);
+	if (np) {
+		vtg->slave = of_vtg_find(np);
+
+		if (!vtg->slave)
+			return -EPROBE_DEFER;
+	} else {
+		vtg->irq = platform_get_irq(pdev, 0);
+		if (IS_ERR_VALUE(vtg->irq)) {
+			DRM_ERROR("Failed to get VTG interrupt\n");
+			return vtg->irq;
+		}
+
+		snprintf(irq_name, sizeof(irq_name), "vsync-%s",
+				dev_name(vtg->dev));
+
+		RAW_INIT_NOTIFIER_HEAD(&vtg->notifier_list);
+
+		ret = devm_request_threaded_irq(dev, vtg->irq, vtg_irq,
+				vtg_irq_thread, IRQF_ONESHOT, irq_name, vtg);
+		if (IS_ERR_VALUE(ret)) {
+			DRM_ERROR("Failed to register VTG interrupt\n");
+			return ret;
+		}
+	}
+
+	vtg_register(vtg);
+	platform_set_drvdata(pdev, vtg);
+
+	DRM_INFO("%s %s\n", __func__, dev_name(vtg->dev));
+
+	return 0;
+}
+
+static int vtg_remove(struct platform_device *pdev)
+{
+	return 0;
+}
+
+static const struct of_device_id vtg_of_match[] = {
+	{ .compatible = "st,vtg", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, vtg_of_match);
+
+struct platform_driver sti_vtg_driver = {
+	.driver = {
+		.name = "sti-vtg",
+		.owner = THIS_MODULE,
+		.of_match_table = vtg_of_match,
+	},
+	.probe	= vtg_probe,
+	.remove = vtg_remove,
+};
+
+module_platform_driver(sti_vtg_driver);
+
+MODULE_AUTHOR("Benjamin Gaignard <benjamin.gaignard@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics SoC DRM driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/gpu/drm/sti/sti_vtg.h b/drivers/gpu/drm/sti/sti_vtg.h
new file mode 100644
index 0000000..e84d23f
--- /dev/null
+++ b/drivers/gpu/drm/sti/sti_vtg.h
@@ -0,0 +1,28 @@ 
+/*
+ * Copyright (C) STMicroelectronics SA 2014
+ * Author: Benjamin Gaignard <benjamin.gaignard@st.com> for STMicroelectronics.
+ * License terms:  GNU General Public License (GPL), version 2
+ */
+
+#ifndef _STI_VTG_H_
+#define _STI_VTG_H_
+
+#define VTG_TOP_FIELD_EVENT     1
+#define VTG_BOTTOM_FIELD_EVENT  2
+
+struct sti_vtg;
+struct drm_display_mode;
+struct notifier_block;
+
+struct sti_vtg *of_vtg_find(struct device_node *np);
+void sti_vtg_set_config(struct sti_vtg *vtg,
+		const struct drm_display_mode *mode);
+int sti_vtg_register_client(struct sti_vtg *vtg,
+		struct notifier_block *nb, int crtc_id);
+int sti_vtg_unregister_client(struct sti_vtg *vtg,
+		struct notifier_block *nb);
+
+u32 sti_vtg_get_line_number(struct drm_display_mode mode, int y);
+u32 sti_vtg_get_pixel_number(struct drm_display_mode mode, int x);
+
+#endif