linux/drivers/gpu/drm/aspeed/aspeed_gfx_drv.c

266 lines
6.5 KiB
C

// 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 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 + 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 = to_aspeed_gfx(drm);
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);
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_CMA_FOPS(fops);
static struct drm_driver aspeed_gfx_driver = {
.driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
.gem_create_object = drm_gem_cma_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 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;
ret = drm_dev_register(&priv->drm, 0);
if (ret)
goto err_unload;
drm_fbdev_generic_setup(&priv->drm, 32);
return 0;
err_unload:
aspeed_gfx_unload(&priv->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);
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");