[PATCH v3 0/3] soc: amlogic: add meson-canvas

[PATCH v3 0/3] soc: amlogic: add meson-canvas

[Maxime Jourdan]

Amlogic SoCs feature a set of 256 canvas that act as pixel buffer
descriptors. Some IPs like the display and video decoders access those
pixels by using canvas IDs rather than direct phy addresses.

As such, allocating/manipulating canvases can be done concurrently and
there is a need for a standalone, lock-aware canvas provider module.

Currently, canvas code lies in the drm/meson module as it is the sole
user.

This patchset adds such canvas provider module.

Changes since v2: [1]
 - Don't include the drm changes in the serie.
 - Remove the syscon node in the dts and doc
 - Rename meson_canvas_setup to meson_canvas_config

Changes since v1: [0]
 - Convert ops struct to a public API
 - Added comments
 - Hid the of-node probe code behind meson_canvas_get
 - Changed device lock to a spinlock with irqsave

[0]: https://lkml.org/lkml/2018/8/1/1512
[1]: https://lkml.org/lkml/2018/8/7/894

Maxime Jourdan (3):
  dt-bindings: soc: amlogic: add meson-canvas documentation
  soc: amlogic: add meson-canvas driver
  ARM64: dts: meson-gx: add dmcbus and canvas nodes.

 .../bindings/soc/amlogic/amlogic,canvas.txt   |  29 +++
 arch/arm64/boot/dts/amlogic/meson-gx.dtsi     |  13 ++
 drivers/soc/amlogic/Kconfig                   |   7 +
 drivers/soc/amlogic/Makefile                  |   1 +
 drivers/soc/amlogic/meson-canvas.c            | 185 ++++++++++++++++++
 include/linux/soc/amlogic/meson-canvas.h      |  65 ++++++
 6 files changed, 300 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/soc/amlogic/amlogic,canvas.txt
 create mode 100644 drivers/soc/amlogic/meson-canvas.c
 create mode 100644 include/linux/soc/amlogic/meson-canvas.h

-- 
2.18.0

[PATCH v3 1/3] dt-bindings: soc: amlogic: add meson-canvas documentation

[Maxime Jourdan]

DT bindings doc for amlogic,meson-canvas

Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Maxime Jourdan <mjourdan@baylibre.com>
---
 .../bindings/soc/amlogic/amlogic,canvas.txt   | 29 +++++++++++++++++++
 1 file changed, 29 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/soc/amlogic/amlogic,canvas.txt

diff --git a/Documentation/devicetree/bindings/soc/amlogic/amlogic,canvas.txt b/Documentation/devicetree/bindings/soc/amlogic/amlogic,canvas.txt
new file mode 100644
index 000000000000..436d2106e80d
--- /dev/null
+++ b/Documentation/devicetree/bindings/soc/amlogic/amlogic,canvas.txt
@@ -0,0 +1,29 @@
+Amlogic Canvas
+================================
+
+A canvas is a collection of metadata that describes a pixel buffer.
+Those metadata include: width, height, phyaddr, wrapping, block mode
+and endianness.
+
+Many IPs within Amlogic SoCs rely on canvas indexes to read/write pixel data
+rather than use the phy addresses directly. For instance, this is the case for
+the video decoders and the display.
+
+Amlogic SoCs have 256 canvas.
+
+Device Tree Bindings:
+---------------------
+
+Video Lookup Table
+--------------------------
+
+Required properties:
+- compatible: "amlogic,canvas"
+- reg: Base physical address and size of the canvas registers.
+
+Example:
+
+canvas: video-lut@48 {
+	compatible = "amlogic,canvas";
+	reg = <0x0 0x48 0x0 0x14>;
+};
-- 
2.18.0

[PATCH v3 2/3] soc: amlogic: add meson-canvas driver

[Maxime Jourdan]

Amlogic SoCs have a repository of 256 canvas which they use to
describe pixel buffers.

They contain metadata like width, height, block mode, endianness [..]

Many IPs within those SoCs like vdec/vpu rely on those canvas to read/write
pixels.

Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
Tested-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Maxime Jourdan <mjourdan@baylibre.com>
---
 drivers/soc/amlogic/Kconfig              |   7 +
 drivers/soc/amlogic/Makefile             |   1 +
 drivers/soc/amlogic/meson-canvas.c       | 185 +++++++++++++++++++++++
 include/linux/soc/amlogic/meson-canvas.h |  65 ++++++++
 4 files changed, 258 insertions(+)
 create mode 100644 drivers/soc/amlogic/meson-canvas.c
 create mode 100644 include/linux/soc/amlogic/meson-canvas.h

diff --git a/drivers/soc/amlogic/Kconfig b/drivers/soc/amlogic/Kconfig
index b04f6e4aedbc..2f282b472912 100644
--- a/drivers/soc/amlogic/Kconfig
+++ b/drivers/soc/amlogic/Kconfig
@@ -1,5 +1,12 @@
 menu "Amlogic SoC drivers"
 
+config MESON_CANVAS
+	tristate "Amlogic Meson Canvas driver"
+	depends on ARCH_MESON || COMPILE_TEST
+	default n
+	help
+	  Say yes to support the canvas IP for Amlogic SoCs.
+
 config MESON_GX_SOCINFO
 	bool "Amlogic Meson GX SoC Information driver"
 	depends on ARCH_MESON || COMPILE_TEST
diff --git a/drivers/soc/amlogic/Makefile b/drivers/soc/amlogic/Makefile
index 8fa321893928..0ab16d35ac36 100644
--- a/drivers/soc/amlogic/Makefile
+++ b/drivers/soc/amlogic/Makefile
@@ -1,3 +1,4 @@
+obj-$(CONFIG_MESON_CANVAS) += meson-canvas.o
 obj-$(CONFIG_MESON_GX_SOCINFO) += meson-gx-socinfo.o
 obj-$(CONFIG_MESON_GX_PM_DOMAINS) += meson-gx-pwrc-vpu.o
 obj-$(CONFIG_MESON_MX_SOCINFO) += meson-mx-socinfo.o
diff --git a/drivers/soc/amlogic/meson-canvas.c b/drivers/soc/amlogic/meson-canvas.c
new file mode 100644
index 000000000000..fce33ca76bb6
--- /dev/null
+++ b/drivers/soc/amlogic/meson-canvas.c
@@ -0,0 +1,185 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2018 BayLibre, SAS
+ * Copyright (C) 2015 Amlogic, Inc. All rights reserved.
+ * Copyright (C) 2014 Endless Mobile
+ */
+
+#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/soc/amlogic/meson-canvas.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/io.h>
+
+#define NUM_CANVAS 256
+
+/* DMC Registers */
+#define DMC_CAV_LUT_DATAL	0x00
+	#define CANVAS_WIDTH_LBIT	29
+	#define CANVAS_WIDTH_LWID	3
+#define DMC_CAV_LUT_DATAH	0x04
+	#define CANVAS_WIDTH_HBIT	0
+	#define CANVAS_HEIGHT_BIT	9
+	#define CANVAS_WRAP_BIT		22
+	#define CANVAS_BLKMODE_BIT	24
+	#define CANVAS_ENDIAN_BIT	26
+#define DMC_CAV_LUT_ADDR	0x08
+	#define CANVAS_LUT_WR_EN	BIT(9)
+	#define CANVAS_LUT_RD_EN	BIT(8)
+
+struct meson_canvas {
+	struct device *dev;
+	void __iomem *reg_base;
+	spinlock_t lock; /* canvas device lock */
+	u8 used[NUM_CANVAS];
+};
+
+static void canvas_write(struct meson_canvas *canvas, u32 reg, u32 val)
+{
+	writel_relaxed(val, canvas->reg_base + reg);
+}
+
+static u32 canvas_read(struct meson_canvas *canvas, u32 reg)
+{
+	return readl_relaxed(canvas->reg_base + reg);
+}
+
+struct meson_canvas *meson_canvas_get(struct device *dev)
+{
+	struct device_node *canvas_node;
+	struct platform_device *canvas_pdev;
+
+	canvas_node = of_parse_phandle(dev->of_node, "amlogic,canvas", 0);
+	if (!canvas_node)
+		return ERR_PTR(-ENODEV);
+
+	canvas_pdev = of_find_device_by_node(canvas_node);
+	if (!canvas_pdev)
+		return ERR_PTR(-EPROBE_DEFER);
+
+	return dev_get_drvdata(&canvas_pdev->dev);
+}
+EXPORT_SYMBOL_GPL(meson_canvas_get);
+
+int meson_canvas_config(struct meson_canvas *canvas, u8 canvas_index,
+			u32 addr, u32 stride, u32 height,
+			unsigned int wrap,
+			unsigned int blkmode,
+			unsigned int endian)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&canvas->lock, flags);
+	if (!canvas->used[canvas_index]) {
+		dev_err(canvas->dev,
+			"Trying to setup non allocated canvas %u\n",
+			canvas_index);
+		spin_unlock_irqrestore(&canvas->lock, flags);
+		return -EINVAL;
+	}
+
+	canvas_write(canvas, DMC_CAV_LUT_DATAL,
+		     ((addr + 7) >> 3) |
+		     (((stride + 7) >> 3) << CANVAS_WIDTH_LBIT));
+
+	canvas_write(canvas, DMC_CAV_LUT_DATAH,
+		     ((((stride + 7) >> 3) >> CANVAS_WIDTH_LWID) <<
+						CANVAS_WIDTH_HBIT) |
+		     (height << CANVAS_HEIGHT_BIT) |
+		     (wrap << CANVAS_WRAP_BIT) |
+		     (blkmode << CANVAS_BLKMODE_BIT) |
+		     (endian << CANVAS_ENDIAN_BIT));
+
+	canvas_write(canvas, DMC_CAV_LUT_ADDR,
+		     CANVAS_LUT_WR_EN | canvas_index);
+
+	/* Force a read-back to make sure everything is flushed. */
+	canvas_read(canvas, DMC_CAV_LUT_DATAH);
+	spin_unlock_irqrestore(&canvas->lock, flags);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(meson_canvas_config);
+
+int meson_canvas_alloc(struct meson_canvas *canvas, u8 *canvas_index)
+{
+	int i;
+	unsigned long flags;
+
+	spin_lock_irqsave(&canvas->lock, flags);
+	for (i = 0; i < NUM_CANVAS; ++i) {
+		if (!canvas->used[i]) {
+			canvas->used[i] = 1;
+			spin_unlock_irqrestore(&canvas->lock, flags);
+			*canvas_index = i;
+			return 0;
+		}
+	}
+	spin_unlock_irqrestore(&canvas->lock, flags);
+
+	dev_err(canvas->dev, "No more canvas available\n");
+	return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(meson_canvas_alloc);
+
+int meson_canvas_free(struct meson_canvas *canvas, u8 canvas_index)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&canvas->lock, flags);
+	if (!canvas->used[canvas_index]) {
+		dev_err(canvas->dev,
+			"Trying to free unused canvas %u\n", canvas_index);
+		spin_unlock_irqrestore(&canvas->lock, flags);
+		return -EINVAL;
+	}
+	canvas->used[canvas_index] = 0;
+	spin_unlock_irqrestore(&canvas->lock, flags);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(meson_canvas_free);
+
+static int meson_canvas_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct meson_canvas *canvas;
+	struct device *dev = &pdev->dev;
+
+	canvas = devm_kzalloc(dev, sizeof(*canvas), GFP_KERNEL);
+	if (!canvas)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	canvas->reg_base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(canvas->reg_base))
+		return PTR_ERR(canvas->reg_base);
+
+	canvas->dev = dev;
+	spin_lock_init(&canvas->lock);
+	dev_set_drvdata(dev, canvas);
+
+	return 0;
+}
+
+static const struct of_device_id canvas_dt_match[] = {
+	{ .compatible = "amlogic,canvas" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, canvas_dt_match);
+
+static struct platform_driver meson_canvas_driver = {
+	.probe = meson_canvas_probe,
+	.driver = {
+		.name = "amlogic-canvas",
+		.of_match_table = canvas_dt_match,
+	},
+};
+module_platform_driver(meson_canvas_driver);
+
+MODULE_DESCRIPTION("Amlogic Canvas driver");
+MODULE_AUTHOR("Maxime Jourdan <mjourdan@baylibre.com>");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/soc/amlogic/meson-canvas.h b/include/linux/soc/amlogic/meson-canvas.h
new file mode 100644
index 000000000000..3dcfdabbef74
--- /dev/null
+++ b/include/linux/soc/amlogic/meson-canvas.h
@@ -0,0 +1,65 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2018 BayLibre, SAS
+ */
+#ifndef __SOC_MESON_CANVAS_H
+#define __SOC_MESON_CANVAS_H
+
+#include <linux/kernel.h>
+
+#define MESON_CANVAS_WRAP_NONE	0x00
+#define MESON_CANVAS_WRAP_X	0x01
+#define MESON_CANVAS_WRAP_Y	0x02
+
+#define MESON_CANVAS_BLKMODE_LINEAR	0x00
+#define MESON_CANVAS_BLKMODE_32x32	0x01
+#define MESON_CANVAS_BLKMODE_64x64	0x02
+
+#define MESON_CANVAS_ENDIAN_SWAP16	0x1
+#define MESON_CANVAS_ENDIAN_SWAP32	0x3
+#define MESON_CANVAS_ENDIAN_SWAP64	0x7
+#define MESON_CANVAS_ENDIAN_SWAP128	0xf
+
+struct meson_canvas;
+
+/**
+ * meson_canvas_get() - get a canvas provider instance
+ *
+ * @dev: consumer device pointer
+ */
+struct meson_canvas *meson_canvas_get(struct device *dev);
+
+/**
+ * meson_canvas_alloc() - take ownership of a canvas
+ *
+ * @canvas: canvas provider instance retrieved from meson_canvas_get()
+ * @canvas_index: will be filled with the canvas ID
+ */
+int meson_canvas_alloc(struct meson_canvas *canvas, u8 *canvas_index);
+
+/**
+ * meson_canvas_free() - remove ownership from a canvas
+ *
+ * @canvas: canvas provider instance retrieved from meson_canvas_get()
+ * @canvas_index: canvas ID that was obtained via meson_canvas_alloc()
+ */
+int meson_canvas_free(struct meson_canvas *canvas, u8 canvas_index);
+
+/**
+ * meson_canvas_config() - configure a canvas
+ *
+ * @canvas: canvas provider instance retrieved from meson_canvas_get()
+ * @canvas_index: canvas ID that was obtained via meson_canvas_alloc()
+ * @addr: physical address to the pixel buffer
+ * @stride: width of the buffer
+ * @height: height of the buffer
+ * @wrap: undocumented
+ * @blkmode: block mode (linear, 32x32, 64x64)
+ * @endian: byte swapping (swap16, swap32, swap64, swap128)
+ */
+int meson_canvas_config(struct meson_canvas *canvas, u8 canvas_index,
+			u32 addr, u32 stride, u32 height,
+			unsigned int wrap, unsigned int blkmode,
+			unsigned int endian);
+
+#endif
-- 
2.18.0

[PATCH v3 3/3] ARM64: dts: meson-gx: add dmcbus and canvas nodes.

[Maxime Jourdan]

DMC is a small memory region with various registers,
including the ones needed for the canvas module.

Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
Signed-off-by: Maxime Jourdan <mjourdan@baylibre.com>
---
 arch/arm64/boot/dts/amlogic/meson-gx.dtsi | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/arch/arm64/boot/dts/amlogic/meson-gx.dtsi b/arch/arm64/boot/dts/amlogic/meson-gx.dtsi
index b8dc4dbb391b..5dd63ecf8b05 100644
--- a/arch/arm64/boot/dts/amlogic/meson-gx.dtsi
+++ b/arch/arm64/boot/dts/amlogic/meson-gx.dtsi
@@ -423,6 +423,19 @@
 			};
 		};
 
+		dmcbus: bus@c8838000 {
+			compatible = "simple-bus";
+			reg = <0x0 0xc8838000 0x0 0x400>;
+			#address-cells = <2>;
+			#size-cells = <2>;
+			ranges = <0x0 0x0 0x0 0xc8838000 0x0 0x400>;
+
+			canvas: video-lut@48 {
+				compatible = "amlogic,canvas";
+				reg = <0x0 0x48 0x0 0x14>;
+			};
+		};
+
 		hiubus: bus@c883c000 {
 			compatible = "simple-bus";
 			reg = <0x0 0xc883c000 0x0 0x2000>;
-- 
2.18.0

Re: [PATCH v3 1/3] dt-bindings: soc: amlogic: add meson-canvas documentation

[Rob Herring]

On Thu, 23 Aug 2018 13:49:52 +0200, Maxime Jourdan wrote:
> DT bindings doc for amlogic,meson-canvas
> 
> Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
> Signed-off-by: Maxime Jourdan <mjourdan@baylibre.com>
> ---
>  .../bindings/soc/amlogic/amlogic,canvas.txt   | 29 +++++++++++++++++++
>  1 file changed, 29 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/soc/amlogic/amlogic,canvas.txt
> 

Reviewed-by: Rob Herring <robh@kernel.org>

Re: [PATCH v3 3/3] ARM64: dts: meson-gx: add dmcbus and canvas nodes.

[Maxime Jourdan]

Hi Kevin,

If you don't mind, please change the title from "ARM64" to "arm64" if
this gets merged.

Thanks!

Maxime

Re: [PATCH v3 2/3] soc: amlogic: add meson-canvas driver

[Maxime Jourdan]

Hi Kevin,

Please create an immutable tag for this patch, as this is a hard
dependency for the video decoder patches. This will make it easier for
Mauro.

Thanks,
Maxime

Re: [PATCH v3 3/3] ARM64: dts: meson-gx: add dmcbus and canvas nodes.

[Kevin Hilman]

Maxime Jourdan <mjourdan@baylibre.com> writes:

> DMC is a small memory region with various registers,
> including the ones needed for the canvas module.
>
> Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
> Signed-off-by: Maxime Jourdan <mjourdan@baylibre.com>

Applied to v4.20/dt64 with s/ARM64/arm64/ as requested.

Thanks,

Kevin

Re: [PATCH v3 2/3] soc: amlogic: add meson-canvas driver

[Kevin Hilman]

Maxime Jourdan <mjourdan@baylibre.com> writes:

> Amlogic SoCs have a repository of 256 canvas which they use to
> describe pixel buffers.
>
> They contain metadata like width, height, block mode, endianness [..]
>
> Many IPs within those SoCs like vdec/vpu rely on those canvas to read/write
> pixels.
>
> Reviewed-by: Jerome Brunet <jbrunet@baylibre.com>
> Tested-by: Neil Armstrong <narmstrong@baylibre.com>
> Signed-off-by: Maxime Jourdan <mjourdan@baylibre.com>

Applied patches 1,2 to v4.20/drivers and added an
"amlogic-drivers-canvas" tag as requested.

Kevin