drm/mcde: Add new driver for ST-Ericsson MCDE

This adds a new DRM driver for the ST-Ericsson Multi Channel
Display Engine, MCDE display controller.

This hardware has three independent DSI hosts and can composit
and display several memory buffers onto an LCD display. It
was developed for several years inside of ST-Ericsson and
shipped with a few million mobile phones from Sony and Samsung,
as well as with the Snowball community development board.

The driver is currently pretty rudimentary but supports a
simple framebuffer so we can get penguins and graphics when
using these SoCs.

Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190524092019.19355-1-linus.walleij@linaro.org

1 files changed, 572 insertions, 0 deletions

diff --git a/drivers/gpu/drm/mcde/mcde_drv.c b/drivers/gpu/drm/mcde/mcde_drv.c
new file mode 100644
index 000000000000..baf63fb6850a
--- /dev/null
+++ b/drivers/gpu/drm/mcde/mcde_drv.c
@@ -0,0 +1,572 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018 Linus Walleij <linus.walleij@linaro.org>
+ * Parts of this file were based on the MCDE driver by Marcus Lorentzon
+ * (C) ST-Ericsson SA 2013
+ */
+
+/**
+ * DOC: ST-Ericsson MCDE Driver
+ *
+ * The MCDE (short for multi-channel display engine) is a graphics
+ * controller found in the Ux500 chipsets, such as NovaThor U8500.
+ * It was initially conceptualized by ST Microelectronics for the
+ * successor of the Nomadik line, STn8500 but productified in the
+ * ST-Ericsson U8500 where is was used for mass-market deployments
+ * in Android phones from Samsung and Sony Ericsson.
+ *
+ * It can do 1080p30 on SDTV CCIR656, DPI-2, DBI-2 or DSI for
+ * panels with or without frame buffering and can convert most
+ * input formats including most variants of RGB and YUV.
+ *
+ * The hardware has four display pipes, and the layout is a little
+ * bit like this:
+ *
+ * Memory     -> Overlay -> Channel -> FIFO -> 5 formatters -> DSI/DPI
+ * External      0..5       0..3       A,B,    3 x DSI         bridge
+ * source 0..9                         C0,C1   2 x DPI
+ *
+ * FIFOs A and B are for LCD and HDMI while FIFO CO/C1 are for
+ * panels with embedded buffer.
+ * 3 of the formatters are for DSI.
+ * 2 of the formatters are for DPI.
+ *
+ * Behind the formatters are the DSI or DPI ports that route to
+ * the external pins of the chip. As there are 3 DSI ports and one
+ * DPI port, it is possible to configure up to 4 display pipelines
+ * (effectively using channels 0..3) for concurrent use.
+ *
+ * In the current DRM/KMS setup, we use one external source, one overlay,
+ * one FIFO and one formatter which we connect to the simple CMA framebuffer
+ * helpers. We then provide a bridge to the DSI port, and on the DSI port
+ * bridge we connect hang a panel bridge or other bridge. This may be subject
+ * to change as we exploit more of the hardware capabilities.
+ *
+ * TODO:
+ * - Enabled damaged rectangles using drm_plane_enable_fb_damage_clips()
+ *   so we can selectively just transmit the damaged area to a
+ *   command-only display.
+ * - Enable mixing of more planes, possibly at the cost of moving away
+ *   from using the simple framebuffer pipeline.
+ * - Enable output to bridges such as the AV8100 HDMI encoder from
+ *   the DSI bridge.
+ */
+
+#include <linux/clk.h>
+#include <linux/component.h>
+#include <linux/dma-buf.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_bridge.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_fb_cma_helper.h>
+#include <drm/drm_fb_helper.h>
+#include <drm/drm_gem.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_gem_framebuffer_helper.h>
+#include <drm/drm_of.h>
+#include <drm/drm_probe_helper.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_vblank.h>
+
+#include "mcde_drm.h"
+
+#define DRIVER_DESC	"DRM module for MCDE"
+
+#define MCDE_CR 0x00000000
+#define MCDE_CR_IFIFOEMPTYLINECOUNT_V422_SHIFT 0
+#define MCDE_CR_IFIFOEMPTYLINECOUNT_V422_MASK 0x0000003F
+#define MCDE_CR_IFIFOCTRLEN BIT(15)
+#define MCDE_CR_UFRECOVERY_MODE_V422 BIT(16)
+#define MCDE_CR_WRAP_MODE_V422_SHIFT BIT(17)
+#define MCDE_CR_AUTOCLKG_EN BIT(30)
+#define MCDE_CR_MCDEEN BIT(31)
+
+#define MCDE_CONF0 0x00000004
+#define MCDE_CONF0_SYNCMUX0 BIT(0)
+#define MCDE_CONF0_SYNCMUX1 BIT(1)
+#define MCDE_CONF0_SYNCMUX2 BIT(2)
+#define MCDE_CONF0_SYNCMUX3 BIT(3)
+#define MCDE_CONF0_SYNCMUX4 BIT(4)
+#define MCDE_CONF0_SYNCMUX5 BIT(5)
+#define MCDE_CONF0_SYNCMUX6 BIT(6)
+#define MCDE_CONF0_SYNCMUX7 BIT(7)
+#define MCDE_CONF0_IFIFOCTRLWTRMRKLVL_SHIFT 12
+#define MCDE_CONF0_IFIFOCTRLWTRMRKLVL_MASK 0x00007000
+#define MCDE_CONF0_OUTMUX0_SHIFT 16
+#define MCDE_CONF0_OUTMUX0_MASK 0x00070000
+#define MCDE_CONF0_OUTMUX1_SHIFT 19
+#define MCDE_CONF0_OUTMUX1_MASK 0x00380000
+#define MCDE_CONF0_OUTMUX2_SHIFT 22
+#define MCDE_CONF0_OUTMUX2_MASK 0x01C00000
+#define MCDE_CONF0_OUTMUX3_SHIFT 25
+#define MCDE_CONF0_OUTMUX3_MASK 0x0E000000
+#define MCDE_CONF0_OUTMUX4_SHIFT 28
+#define MCDE_CONF0_OUTMUX4_MASK 0x70000000
+
+#define MCDE_SSP 0x00000008
+#define MCDE_AIS 0x00000100
+#define MCDE_IMSCERR 0x00000110
+#define MCDE_RISERR 0x00000120
+#define MCDE_MISERR 0x00000130
+#define MCDE_SISERR 0x00000140
+
+#define MCDE_PID 0x000001FC
+#define MCDE_PID_METALFIX_VERSION_SHIFT 0
+#define MCDE_PID_METALFIX_VERSION_MASK 0x000000FF
+#define MCDE_PID_DEVELOPMENT_VERSION_SHIFT 8
+#define MCDE_PID_DEVELOPMENT_VERSION_MASK 0x0000FF00
+#define MCDE_PID_MINOR_VERSION_SHIFT 16
+#define MCDE_PID_MINOR_VERSION_MASK 0x00FF0000
+#define MCDE_PID_MAJOR_VERSION_SHIFT 24
+#define MCDE_PID_MAJOR_VERSION_MASK 0xFF000000
+
+static const struct drm_mode_config_funcs mcde_mode_config_funcs = {
+	.fb_create = drm_gem_fb_create_with_dirty,
+	.atomic_check = drm_atomic_helper_check,
+	.atomic_commit = drm_atomic_helper_commit,
+};
+
+static const struct drm_mode_config_helper_funcs mcde_mode_config_helpers = {
+	/*
+	 * Using this function is necessary to commit atomic updates
+	 * that need the CRTC to be enabled before a commit, as is
+	 * the case with e.g. DSI displays.
+	 */
+	.atomic_commit_tail = drm_atomic_helper_commit_tail_rpm,
+};
+
+static irqreturn_t mcde_irq(int irq, void *data)
+{
+	struct mcde *mcde = data;
+	u32 val;
+
+	val = readl(mcde->regs + MCDE_MISERR);
+
+	mcde_display_irq(mcde);
+
+	if (val)
+		dev_info(mcde->dev, "some error IRQ\n");
+	writel(val, mcde->regs + MCDE_RISERR);
+
+	return IRQ_HANDLED;
+}
+
+static int mcde_modeset_init(struct drm_device *drm)
+{
+	struct drm_mode_config *mode_config;
+	struct mcde *mcde = drm->dev_private;
+	int ret;
+
+	if (!mcde->bridge) {
+		dev_err(drm->dev, "no display output bridge yet\n");
+		return -EPROBE_DEFER;
+	}
+
+	mode_config = &drm->mode_config;
+	mode_config->funcs = &mcde_mode_config_funcs;
+	mode_config->helper_private = &mcde_mode_config_helpers;
+	/* This hardware can do 1080p */
+	mode_config->min_width = 1;
+	mode_config->max_width = 1920;
+	mode_config->min_height = 1;
+	mode_config->max_height = 1080;
+
+	/*
+	 * Currently we only support vblank handling on the DSI bridge, using
+	 * TE synchronization. If TE sync is not set up, it is still possible
+	 * to push out a single update on demand, but this is hard for DRM to
+	 * exploit.
+	 */
+	if (mcde->te_sync) {
+		ret = drm_vblank_init(drm, 1);
+		if (ret) {
+			dev_err(drm->dev, "failed to init vblank\n");
+			goto out_config;
+		}
+	}
+
+	ret = mcde_display_init(drm);
+	if (ret) {
+		dev_err(drm->dev, "failed to init display\n");
+		goto out_config;
+	}
+
+	/*
+	 * Attach the DSI bridge
+	 *
+	 * TODO: when adding support for the DPI bridge or several DSI bridges,
+	 * we selectively connect the bridge(s) here instead of this simple
+	 * attachment.
+	 */
+	ret = drm_simple_display_pipe_attach_bridge(&mcde->pipe,
+						    mcde->bridge);
+	if (ret) {
+		dev_err(drm->dev, "failed to attach display output bridge\n");
+		goto out_config;
+	}
+
+	drm_mode_config_reset(drm);
+	drm_kms_helper_poll_init(drm);
+	drm_fbdev_generic_setup(drm, 32);
+
+	return 0;
+
+out_config:
+	drm_mode_config_cleanup(drm);
+	return ret;
+}
+
+static void mcde_release(struct drm_device *drm)
+{
+	struct mcde *mcde = drm->dev_private;
+
+	drm_mode_config_cleanup(drm);
+	drm_dev_fini(drm);
+	kfree(mcde);
+}
+
+DEFINE_DRM_GEM_CMA_FOPS(drm_fops);
+
+static struct drm_driver mcde_drm_driver = {
+	.driver_features =
+		DRIVER_MODESET | DRIVER_GEM | DRIVER_PRIME | DRIVER_ATOMIC,
+	.release = mcde_release,
+	.lastclose = drm_fb_helper_lastclose,
+	.ioctls = NULL,
+	.fops = &drm_fops,
+	.name = "mcde",
+	.desc = DRIVER_DESC,
+	.date = "20180529",
+	.major = 1,
+	.minor = 0,
+	.patchlevel = 0,
+	.dumb_create = drm_gem_cma_dumb_create,
+	.gem_free_object_unlocked = drm_gem_cma_free_object,
+	.gem_vm_ops = &drm_gem_cma_vm_ops,
+
+	.prime_handle_to_fd = drm_gem_prime_handle_to_fd,
+	.prime_fd_to_handle = drm_gem_prime_fd_to_handle,
+	.gem_prime_import = drm_gem_prime_import,
+	.gem_prime_export = drm_gem_prime_export,
+	.gem_prime_get_sg_table	= drm_gem_cma_prime_get_sg_table,
+	.gem_prime_import_sg_table = drm_gem_cma_prime_import_sg_table,
+	.gem_prime_vmap = drm_gem_cma_prime_vmap,
+	.gem_prime_vunmap = drm_gem_cma_prime_vunmap,
+	.gem_prime_mmap = drm_gem_cma_prime_mmap,
+};
+
+static int mcde_drm_bind(struct device *dev)
+{
+	struct drm_device *drm = dev_get_drvdata(dev);
+	int ret;
+
+	drm_mode_config_init(drm);
+
+	ret = component_bind_all(drm->dev, drm);
+	if (ret) {
+		dev_err(dev, "can't bind component devices\n");
+		return ret;
+	}
+
+	ret = mcde_modeset_init(drm);
+	if (ret)
+		goto unbind;
+
+	ret = drm_dev_register(drm, 0);
+	if (ret < 0)
+		goto unbind;
+
+	return 0;
+
+unbind:
+	component_unbind_all(drm->dev, drm);
+	return ret;
+}
+
+static void mcde_drm_unbind(struct device *dev)
+{
+	struct drm_device *drm = dev_get_drvdata(dev);
+
+	drm_dev_unregister(drm);
+	drm_atomic_helper_shutdown(drm);
+	component_unbind_all(drm->dev, drm);
+}
+
+static const struct component_master_ops mcde_drm_comp_ops = {
+	.bind = mcde_drm_bind,
+	.unbind = mcde_drm_unbind,
+};
+
+static struct platform_driver *const mcde_component_drivers[] = {
+	&mcde_dsi_driver,
+};
+
+static int mcde_compare_dev(struct device *dev, void *data)
+{
+	return dev == data;
+}
+
+static int mcde_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct drm_device *drm;
+	struct mcde *mcde;
+	struct component_match *match;
+	struct resource *res;
+	u32 pid;
+	u32 val;
+	int irq;
+	int ret;
+	int i;
+
+	mcde = kzalloc(sizeof(*mcde), GFP_KERNEL);
+	if (!mcde)
+		return -ENOMEM;
+	mcde->dev = dev;
+
+	ret = drm_dev_init(&mcde->drm, &mcde_drm_driver, dev);
+	if (ret) {
+		kfree(mcde);
+		return ret;
+	}
+	drm = &mcde->drm;
+	drm->dev_private = mcde;
+	platform_set_drvdata(pdev, drm);
+
+	/* Enable use of the TE signal and interrupt */
+	mcde->te_sync = true;
+	/* Enable continuous updates: this is what Linux' framebuffer expects */
+	mcde->oneshot_mode = false;
+	drm->dev_private = mcde;
+
+	/* First obtain and turn on the main power */
+	mcde->epod = devm_regulator_get(dev, "epod");
+	if (IS_ERR(mcde->epod)) {
+		ret = PTR_ERR(mcde->epod);
+		dev_err(dev, "can't get EPOD regulator\n");
+		goto dev_unref;
+	}
+	ret = regulator_enable(mcde->epod);
+	if (ret) {
+		dev_err(dev, "can't enable EPOD regulator\n");
+		goto dev_unref;
+	}
+	mcde->vana = devm_regulator_get(dev, "vana");
+	if (IS_ERR(mcde->vana)) {
+		ret = PTR_ERR(mcde->vana);
+		dev_err(dev, "can't get VANA regulator\n");
+		goto regulator_epod_off;
+	}
+	ret = regulator_enable(mcde->vana);
+	if (ret) {
+		dev_err(dev, "can't enable VANA regulator\n");
+		goto regulator_epod_off;
+	}
+	/*
+	 * The vendor code uses ESRAM (onchip RAM) and need to activate
+	 * the v-esram34 regulator, but we don't use that yet
+	 */
+
+	/* Clock the silicon so we can access the registers */
+	mcde->mcde_clk = devm_clk_get(dev, "mcde");
+	if (IS_ERR(mcde->mcde_clk)) {
+		dev_err(dev, "unable to get MCDE main clock\n");
+		ret = PTR_ERR(mcde->mcde_clk);
+		goto regulator_off;
+	}
+	ret = clk_prepare_enable(mcde->mcde_clk);
+	if (ret) {
+		dev_err(dev, "failed to enable MCDE main clock\n");
+		goto regulator_off;
+	}
+	dev_info(dev, "MCDE clk rate %lu Hz\n", clk_get_rate(mcde->mcde_clk));
+
+	mcde->lcd_clk = devm_clk_get(dev, "lcd");
+	if (IS_ERR(mcde->lcd_clk)) {
+		dev_err(dev, "unable to get LCD clock\n");
+		ret = PTR_ERR(mcde->lcd_clk);
+		goto clk_disable;
+	}
+	mcde->hdmi_clk = devm_clk_get(dev, "hdmi");
+	if (IS_ERR(mcde->hdmi_clk)) {
+		dev_err(dev, "unable to get HDMI clock\n");
+		ret = PTR_ERR(mcde->hdmi_clk);
+		goto clk_disable;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	mcde->regs = devm_ioremap_resource(dev, res);
+	if (IS_ERR(mcde->regs)) {
+		dev_err(dev, "no MCDE regs\n");
+		ret = -EINVAL;
+		goto clk_disable;
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	if (!irq) {
+		ret = -EINVAL;
+		goto clk_disable;
+	}
+
+	ret = devm_request_irq(dev, irq, mcde_irq, 0, "mcde", mcde);
+	if (ret) {
+		dev_err(dev, "failed to request irq %d\n", ret);
+		goto clk_disable;
+	}
+
+	/*
+	 * Check hardware revision, we only support U8500v2 version
+	 * as this was the only version used for mass market deployment,
+	 * but surely you can add more versions if you have them and
+	 * need them.
+	 */
+	pid = readl(mcde->regs + MCDE_PID);
+	dev_info(dev, "found MCDE HW revision %d.%d (dev %d, metal fix %d)\n",
+		 (pid & MCDE_PID_MAJOR_VERSION_MASK)
+		 >> MCDE_PID_MAJOR_VERSION_SHIFT,
+		 (pid & MCDE_PID_MINOR_VERSION_MASK)
+		 >> MCDE_PID_MINOR_VERSION_SHIFT,
+		 (pid & MCDE_PID_DEVELOPMENT_VERSION_MASK)
+		 >> MCDE_PID_DEVELOPMENT_VERSION_SHIFT,
+		 (pid & MCDE_PID_METALFIX_VERSION_MASK)
+		 >> MCDE_PID_METALFIX_VERSION_SHIFT);
+	if (pid != 0x03000800) {
+		dev_err(dev, "unsupported hardware revision\n");
+		ret = -ENODEV;
+		goto clk_disable;
+	}
+
+	/* Set up the main control, watermark level at 7 */
+	val = 7 << MCDE_CONF0_IFIFOCTRLWTRMRKLVL_SHIFT;
+	/* 24 bits DPI: connect LSB Ch B to D[0:7] */
+	val |= 3 << MCDE_CONF0_OUTMUX0_SHIFT;
+	/* TV out: connect LSB Ch B to D[8:15] */
+	val |= 3 << MCDE_CONF0_OUTMUX1_SHIFT;
+	/* Don't care about this muxing */
+	val |= 0 << MCDE_CONF0_OUTMUX2_SHIFT;
+	/* 24 bits DPI: connect MID Ch B to D[24:31] */
+	val |= 4 << MCDE_CONF0_OUTMUX3_SHIFT;
+	/* 5: 24 bits DPI: connect MSB Ch B to D[32:39] */
+	val |= 5 << MCDE_CONF0_OUTMUX4_SHIFT;
+	/* Syncmux bits zero: DPI channel A and B on output pins A and B resp */
+	writel(val, mcde->regs + MCDE_CONF0);
+
+	/* Enable automatic clock gating */
+	val = readl(mcde->regs + MCDE_CR);
+	val |= MCDE_CR_MCDEEN | MCDE_CR_AUTOCLKG_EN;
+	writel(val, mcde->regs + MCDE_CR);
+
+	/* Clear any pending interrupts */
+	mcde_display_disable_irqs(mcde);
+	writel(0, mcde->regs + MCDE_IMSCERR);
+	writel(0xFFFFFFFF, mcde->regs + MCDE_RISERR);
+
+	/* Spawn child devices for the DSI ports */
+	devm_of_platform_populate(dev);
+
+	/* Create something that will match the subdrivers when we bind */
+	for (i = 0; i < ARRAY_SIZE(mcde_component_drivers); i++) {
+		struct device_driver *drv = &mcde_component_drivers[i]->driver;
+		struct device *p = NULL, *d;
+
+		while ((d = bus_find_device(&platform_bus_type, p, drv,
+					    (void *)platform_bus_type.match))) {
+			put_device(p);
+			component_match_add(dev, &match, mcde_compare_dev, d);
+			p = d;
+		}
+		put_device(p);
+	}
+	if (IS_ERR(match)) {
+		dev_err(dev, "could not create component match\n");
+		ret = PTR_ERR(match);
+		goto clk_disable;
+	}
+	ret = component_master_add_with_match(&pdev->dev, &mcde_drm_comp_ops,
+					      match);
+	if (ret) {
+		dev_err(dev, "failed to add component master\n");
+		goto clk_disable;
+	}
+	return 0;
+
+clk_disable:
+	clk_disable_unprepare(mcde->mcde_clk);
+regulator_off:
+	regulator_disable(mcde->vana);
+regulator_epod_off:
+	regulator_disable(mcde->epod);
+dev_unref:
+	drm_dev_put(drm);
+	return ret;
+
+}
+
+static int mcde_remove(struct platform_device *pdev)
+{
+	struct drm_device *drm = platform_get_drvdata(pdev);
+	struct mcde *mcde = drm->dev_private;
+
+	component_master_del(&pdev->dev, &mcde_drm_comp_ops);
+	clk_disable_unprepare(mcde->mcde_clk);
+	regulator_disable(mcde->vana);
+	regulator_disable(mcde->epod);
+	drm_dev_put(drm);
+
+	return 0;
+}
+
+static const struct of_device_id mcde_of_match[] = {
+	{
+		.compatible = "ste,mcde",
+	},
+	{},
+};
+
+static struct platform_driver mcde_driver = {
+	.driver = {
+		.name           = "mcde",
+		.of_match_table = of_match_ptr(mcde_of_match),
+	},
+	.probe = mcde_probe,
+	.remove = mcde_remove,
+};
+
+static struct platform_driver *const component_drivers[] = {
+	&mcde_dsi_driver,
+};
+
+static int __init mcde_drm_register(void)
+{
+	int ret;
+
+	ret = platform_register_drivers(component_drivers,
+					ARRAY_SIZE(component_drivers));
+	if (ret)
+		return ret;
+
+	return platform_driver_register(&mcde_driver);
+}
+
+static void __exit mcde_drm_unregister(void)
+{
+	platform_unregister_drivers(component_drivers,
+				    ARRAY_SIZE(component_drivers));
+	platform_driver_unregister(&mcde_driver);
+}
+
+module_init(mcde_drm_register);
+module_exit(mcde_drm_unregister);
+
+MODULE_ALIAS("platform:mcde-drm");
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
+MODULE_LICENSE("GPL");