1 files changed, 383 insertions, 0 deletions
diff --git a/drivers/gpu/drm/aspeed/aspeed_gfx_drv.c b/drivers/gpu/drm/aspeed/aspeed_gfx_drv.c
new file mode 100644
index 000000000..78122b35a
--- /dev/null
+++ b/drivers/gpu/drm/aspeed/aspeed_gfx_drv.c
@@ -0,0 +1,383 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Copyright 2018 IBM Corporation
+
+#include <linux/clk.h>
+#include <linux/dma-mapping.h>
+#include <linux/irq.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_reserved_mem.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_device.h>
+#include <drm/drm_fbdev_dma.h>
+#include <drm/drm_gem_dma_helper.h>
+#include <drm/drm_gem_framebuffer_helper.h>
+#include <drm/drm_module.h>
+#include <drm/drm_probe_helper.h>
+#include <drm/drm_simple_kms_helper.h>
+#include <drm/drm_vblank.h>
+#include <drm/drm_drv.h>
+
+#include "aspeed_gfx.h"
+
+/**
+ * DOC: ASPEED GFX Driver
+ *
+ * This driver is for the ASPEED BMC SoC's 'GFX' display hardware, also called
+ * the 'SOC Display Controller' in the datasheet. This driver runs on the ARM
+ * based BMC systems, unlike the ast driver which runs on a host CPU and is for
+ * a PCIe graphics device.
+ *
+ * The AST2500 supports a total of 3 output paths:
+ *
+ *   1. VGA output, the output target can choose either or both to the DAC
+ *   or DVO interface.
+ *
+ *   2. Graphics CRT output, the output target can choose either or both to
+ *   the DAC or DVO interface.
+ *
+ *   3. Video input from DVO, the video input can be used for video engine
+ *   capture or DAC display output.
+ *
+ * Output options are selected in SCU2C.
+ *
+ * The "VGA mode" device is the PCI attached controller. The "Graphics CRT"
+ * is the ARM's internal display controller.
+ *
+ * The driver only supports a simple configuration consisting of a 40MHz
+ * pixel clock, fixed by hardware limitations, and the VGA output path.
+ *
+ * The driver was written with the 'AST2500 Software Programming Guide' v17,
+ * which is available under NDA from ASPEED.
+ */
+
+struct aspeed_gfx_config {
+	u32 dac_reg;		/* DAC register in SCU */
+	u32 int_clear_reg;	/* Interrupt clear register */
+	u32 vga_scratch_reg;	/* VGA scratch register in SCU */
+	u32 throd_val;		/* Default Threshold Seting */
+	u32 scan_line_max;	/* Max memory size of one scan line */
+};
+
+static const struct aspeed_gfx_config ast2400_config = {
+	.dac_reg = 0x2c,
+	.int_clear_reg = 0x60,
+	.vga_scratch_reg = 0x50,
+	.throd_val = CRT_THROD_LOW(0x1e) | CRT_THROD_HIGH(0x12),
+	.scan_line_max = 64,
+};
+
+static const struct aspeed_gfx_config ast2500_config = {
+	.dac_reg = 0x2c,
+	.int_clear_reg = 0x60,
+	.vga_scratch_reg = 0x50,
+	.throd_val = CRT_THROD_LOW(0x24) | CRT_THROD_HIGH(0x3c),
+	.scan_line_max = 128,
+};
+
+static const struct aspeed_gfx_config ast2600_config = {
+	.dac_reg = 0xc0,
+	.int_clear_reg = 0x68,
+	.vga_scratch_reg = 0x50,
+	.throd_val = CRT_THROD_LOW(0x50) | CRT_THROD_HIGH(0x70),
+	.scan_line_max = 128,
+};
+
+static const struct of_device_id aspeed_gfx_match[] = {
+	{ .compatible = "aspeed,ast2400-gfx", .data = &ast2400_config },
+	{ .compatible = "aspeed,ast2500-gfx", .data = &ast2500_config },
+	{ .compatible = "aspeed,ast2600-gfx", .data = &ast2600_config },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, aspeed_gfx_match);
+
+static const struct drm_mode_config_funcs aspeed_gfx_mode_config_funcs = {
+	.fb_create		= drm_gem_fb_create,
+	.atomic_check		= drm_atomic_helper_check,
+	.atomic_commit		= drm_atomic_helper_commit,
+};
+
+static int aspeed_gfx_setup_mode_config(struct drm_device *drm)
+{
+	int ret;
+
+	ret = drmm_mode_config_init(drm);
+	if (ret)
+		return ret;
+
+	drm->mode_config.min_width = 0;
+	drm->mode_config.min_height = 0;
+	drm->mode_config.max_width = 800;
+	drm->mode_config.max_height = 600;
+	drm->mode_config.funcs = &aspeed_gfx_mode_config_funcs;
+
+	return ret;
+}
+
+static irqreturn_t aspeed_gfx_irq_handler(int irq, void *data)
+{
+	struct drm_device *drm = data;
+	struct aspeed_gfx *priv = to_aspeed_gfx(drm);
+	u32 reg;
+
+	reg = readl(priv->base + CRT_CTRL1);
+
+	if (reg & CRT_CTRL_VERTICAL_INTR_STS) {
+		drm_crtc_handle_vblank(&priv->pipe.crtc);
+		writel(reg, priv->base + priv->int_clr_reg);
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_NONE;
+}
+
+static int aspeed_gfx_load(struct drm_device *drm)
+{
+	struct platform_device *pdev = to_platform_device(drm->dev);
+	struct aspeed_gfx *priv = to_aspeed_gfx(drm);
+	struct device_node *np = pdev->dev.of_node;
+	const struct aspeed_gfx_config *config;
+	const struct of_device_id *match;
+	struct resource *res;
+	int ret;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	priv->base = devm_ioremap_resource(drm->dev, res);
+	if (IS_ERR(priv->base))
+		return PTR_ERR(priv->base);
+
+	match = of_match_device(aspeed_gfx_match, &pdev->dev);
+	if (!match)
+		return -EINVAL;
+	config = match->data;
+
+	priv->dac_reg = config->dac_reg;
+	priv->int_clr_reg = config->int_clear_reg;
+	priv->vga_scratch_reg = config->vga_scratch_reg;
+	priv->throd_val = config->throd_val;
+	priv->scan_line_max = config->scan_line_max;
+
+	priv->scu = syscon_regmap_lookup_by_phandle(np, "syscon");
+	if (IS_ERR(priv->scu)) {
+		priv->scu = syscon_regmap_lookup_by_compatible("aspeed,ast2500-scu");
+		if (IS_ERR(priv->scu)) {
+			dev_err(&pdev->dev, "failed to find SCU regmap\n");
+			return PTR_ERR(priv->scu);
+		}
+	}
+
+	ret = of_reserved_mem_device_init(drm->dev);
+	if (ret) {
+		dev_err(&pdev->dev,
+			"failed to initialize reserved mem: %d\n", ret);
+		return ret;
+	}
+
+	ret = dma_set_mask_and_coherent(drm->dev, DMA_BIT_MASK(32));
+	if (ret) {
+		dev_err(&pdev->dev, "failed to set DMA mask: %d\n", ret);
+		return ret;
+	}
+
+	priv->rst = devm_reset_control_get_exclusive(&pdev->dev, NULL);
+	if (IS_ERR(priv->rst)) {
+		dev_err(&pdev->dev,
+			"missing or invalid reset controller device tree entry");
+		return PTR_ERR(priv->rst);
+	}
+	reset_control_deassert(priv->rst);
+
+	priv->clk = devm_clk_get(drm->dev, NULL);
+	if (IS_ERR(priv->clk)) {
+		dev_err(&pdev->dev,
+			"missing or invalid clk device tree entry");
+		return PTR_ERR(priv->clk);
+	}
+	clk_prepare_enable(priv->clk);
+
+	/* Sanitize control registers */
+	writel(0, priv->base + CRT_CTRL1);
+	writel(0, priv->base + CRT_CTRL2);
+
+	ret = aspeed_gfx_setup_mode_config(drm);
+	if (ret < 0)
+		return ret;
+
+	ret = drm_vblank_init(drm, 1);
+	if (ret < 0) {
+		dev_err(drm->dev, "Failed to initialise vblank\n");
+		return ret;
+	}
+
+	ret = aspeed_gfx_create_output(drm);
+	if (ret < 0) {
+		dev_err(drm->dev, "Failed to create outputs\n");
+		return ret;
+	}
+
+	ret = aspeed_gfx_create_pipe(drm);
+	if (ret < 0) {
+		dev_err(drm->dev, "Cannot setup simple display pipe\n");
+		return ret;
+	}
+
+	ret = devm_request_irq(drm->dev, platform_get_irq(pdev, 0),
+			       aspeed_gfx_irq_handler, 0, "aspeed gfx", drm);
+	if (ret < 0) {
+		dev_err(drm->dev, "Failed to install IRQ handler\n");
+		return ret;
+	}
+
+	drm_mode_config_reset(drm);
+
+	return 0;
+}
+
+static void aspeed_gfx_unload(struct drm_device *drm)
+{
+	drm_kms_helper_poll_fini(drm);
+}
+
+DEFINE_DRM_GEM_DMA_FOPS(fops);
+
+static const struct drm_driver aspeed_gfx_driver = {
+	.driver_features        = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
+	DRM_GEM_DMA_DRIVER_OPS,
+	.fops = &fops,
+	.name = "aspeed-gfx-drm",
+	.desc = "ASPEED GFX DRM",
+	.date = "20180319",
+	.major = 1,
+	.minor = 0,
+};
+
+static ssize_t dac_mux_store(struct device *dev, struct device_attribute *attr,
+			     const char *buf, size_t count)
+{
+	struct aspeed_gfx *priv = dev_get_drvdata(dev);
+	u32 val;
+	int rc;
+
+	rc = kstrtou32(buf, 0, &val);
+	if (rc)
+		return rc;
+
+	if (val > 3)
+		return -EINVAL;
+
+	rc = regmap_update_bits(priv->scu, priv->dac_reg, 0x30000, val << 16);
+	if (rc < 0)
+		return 0;
+
+	return count;
+}
+
+static ssize_t dac_mux_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct aspeed_gfx *priv = dev_get_drvdata(dev);
+	u32 reg;
+	int rc;
+
+	rc = regmap_read(priv->scu, priv->dac_reg, &reg);
+	if (rc)
+		return rc;
+
+	return sprintf(buf, "%u\n", (reg >> 16) & 0x3);
+}
+static DEVICE_ATTR_RW(dac_mux);
+
+static ssize_t
+vga_pw_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct aspeed_gfx *priv = dev_get_drvdata(dev);
+	u32 reg;
+	int rc;
+
+	rc = regmap_read(priv->scu, priv->vga_scratch_reg, &reg);
+	if (rc)
+		return rc;
+
+	return sprintf(buf, "%u\n", reg);
+}
+static DEVICE_ATTR_RO(vga_pw);
+
+static struct attribute *aspeed_sysfs_entries[] = {
+	&dev_attr_vga_pw.attr,
+	&dev_attr_dac_mux.attr,
+	NULL,
+};
+
+static struct attribute_group aspeed_sysfs_attr_group = {
+	.attrs = aspeed_sysfs_entries,
+};
+
+static int aspeed_gfx_probe(struct platform_device *pdev)
+{
+	struct aspeed_gfx *priv;
+	int ret;
+
+	priv = devm_drm_dev_alloc(&pdev->dev, &aspeed_gfx_driver,
+				  struct aspeed_gfx, drm);
+	if (IS_ERR(priv))
+		return PTR_ERR(priv);
+
+	ret = aspeed_gfx_load(&priv->drm);
+	if (ret)
+		return ret;
+
+	platform_set_drvdata(pdev, priv);
+
+	ret = sysfs_create_group(&pdev->dev.kobj, &aspeed_sysfs_attr_group);
+	if (ret)
+		return ret;
+
+	ret = drm_dev_register(&priv->drm, 0);
+	if (ret)
+		goto err_unload;
+
+	drm_fbdev_dma_setup(&priv->drm, 32);
+	return 0;
+
+err_unload:
+	sysfs_remove_group(&pdev->dev.kobj, &aspeed_sysfs_attr_group);
+	aspeed_gfx_unload(&priv->drm);
+
+	return ret;
+}
+
+static void aspeed_gfx_remove(struct platform_device *pdev)
+{
+	struct drm_device *drm = platform_get_drvdata(pdev);
+
+	sysfs_remove_group(&pdev->dev.kobj, &aspeed_sysfs_attr_group);
+	drm_dev_unregister(drm);
+	aspeed_gfx_unload(drm);
+	drm_atomic_helper_shutdown(drm);
+}
+
+static void aspeed_gfx_shutdown(struct platform_device *pdev)
+{
+	drm_atomic_helper_shutdown(platform_get_drvdata(pdev));
+}
+
+static struct platform_driver aspeed_gfx_platform_driver = {
+	.probe		= aspeed_gfx_probe,
+	.remove_new	= aspeed_gfx_remove,
+	.shutdown	= aspeed_gfx_shutdown,
+	.driver = {
+		.name = "aspeed_gfx",
+		.of_match_table = aspeed_gfx_match,
+	},
+};
+
+drm_module_platform_driver(aspeed_gfx_platform_driver);
+
+MODULE_AUTHOR("Joel Stanley <joel@jms.id.au>");
+MODULE_DESCRIPTION("ASPEED BMC DRM/KMS driver");
+MODULE_LICENSE("GPL");