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path: root/drivers/gpu/drm/aspeed/aspeed_gfx_drv.c
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Diffstat (limited to 'drivers/gpu/drm/aspeed/aspeed_gfx_drv.c')
-rw-r--r--drivers/gpu/drm/aspeed/aspeed_gfx_drv.c269
1 files changed, 269 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 000000000000..eeb22eccd1fc
--- /dev/null
+++ b/drivers/gpu/drm/aspeed/aspeed_gfx_drv.c
@@ -0,0 +1,269 @@
+// 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_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_crtc_helper.h>
+#include <drm/drm_device.h>
+#include <drm/drm_fb_cma_helper.h>
+#include <drm/drm_fb_helper.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_gem_framebuffer_helper.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.
+ */
+
+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 void aspeed_gfx_setup_mode_config(struct drm_device *drm)
+{
+ drm_mode_config_init(drm);
+
+ 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;
+}
+
+static irqreturn_t aspeed_gfx_irq_handler(int irq, void *data)
+{
+ struct drm_device *drm = data;
+ struct aspeed_gfx *priv = drm->dev_private;
+ 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 + CRT_CTRL1);
+ 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;
+ struct resource *res;
+ int ret;
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+ drm->dev_private = priv;
+
+ 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);
+
+ 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);
+
+ aspeed_gfx_setup_mode_config(drm);
+
+ 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);
+
+ drm_fbdev_generic_setup(drm, 32);
+
+ return 0;
+}
+
+static void aspeed_gfx_unload(struct drm_device *drm)
+{
+ drm_kms_helper_poll_fini(drm);
+ drm_mode_config_cleanup(drm);
+
+ drm->dev_private = NULL;
+}
+
+DEFINE_DRM_GEM_CMA_FOPS(fops);
+
+static struct drm_driver aspeed_gfx_driver = {
+ .driver_features = DRIVER_GEM | DRIVER_MODESET |
+ DRIVER_PRIME | DRIVER_ATOMIC,
+ .gem_create_object = drm_cma_gem_create_object_default_funcs,
+ .dumb_create = drm_gem_cma_dumb_create,
+ .prime_handle_to_fd = drm_gem_prime_handle_to_fd,
+ .prime_fd_to_handle = drm_gem_prime_fd_to_handle,
+ .gem_prime_import_sg_table = drm_gem_cma_prime_import_sg_table,
+ .gem_prime_mmap = drm_gem_prime_mmap,
+ .fops = &fops,
+ .name = "aspeed-gfx-drm",
+ .desc = "ASPEED GFX DRM",
+ .date = "20180319",
+ .major = 1,
+ .minor = 0,
+};
+
+static const struct of_device_id aspeed_gfx_match[] = {
+ { .compatible = "aspeed,ast2500-gfx" },
+ { }
+};
+
+static int aspeed_gfx_probe(struct platform_device *pdev)
+{
+ struct drm_device *drm;
+ int ret;
+
+ drm = drm_dev_alloc(&aspeed_gfx_driver, &pdev->dev);
+ if (IS_ERR(drm))
+ return PTR_ERR(drm);
+
+ ret = aspeed_gfx_load(drm);
+ if (ret)
+ goto err_free;
+
+ ret = drm_dev_register(drm, 0);
+ if (ret)
+ goto err_unload;
+
+ return 0;
+
+err_unload:
+ aspeed_gfx_unload(drm);
+err_free:
+ drm_dev_put(drm);
+
+ return ret;
+}
+
+static int aspeed_gfx_remove(struct platform_device *pdev)
+{
+ struct drm_device *drm = platform_get_drvdata(pdev);
+
+ drm_dev_unregister(drm);
+ aspeed_gfx_unload(drm);
+ drm_dev_put(drm);
+
+ return 0;
+}
+
+static struct platform_driver aspeed_gfx_platform_driver = {
+ .probe = aspeed_gfx_probe,
+ .remove = aspeed_gfx_remove,
+ .driver = {
+ .name = "aspeed_gfx",
+ .of_match_table = aspeed_gfx_match,
+ },
+};
+
+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");