diff options
Diffstat (limited to 'drivers/gpu/drm/aspeed/aspeed_gfx_drv.c')
-rw-r--r-- | drivers/gpu/drm/aspeed/aspeed_gfx_drv.c | 269 |
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"); |