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1// SPDX-License-Identifier: GPL-2.0+2// Copyright 2018 IBM Corporation3 4#include <linux/clk.h>5#include <linux/dma-mapping.h>6#include <linux/irq.h>7#include <linux/mfd/syscon.h>8#include <linux/module.h>9#include <linux/mod_devicetable.h>10#include <linux/of_reserved_mem.h>11#include <linux/platform_device.h>12#include <linux/property.h>13#include <linux/regmap.h>14#include <linux/reset.h>15 16#include <drm/drm_atomic_helper.h>17#include <drm/drm_device.h>18#include <drm/drm_fbdev_dma.h>19#include <drm/drm_gem_dma_helper.h>20#include <drm/drm_gem_framebuffer_helper.h>21#include <drm/drm_module.h>22#include <drm/drm_probe_helper.h>23#include <drm/drm_simple_kms_helper.h>24#include <drm/drm_vblank.h>25#include <drm/drm_drv.h>26 27#include "aspeed_gfx.h"28 29/**30 * DOC: ASPEED GFX Driver31 *32 * This driver is for the ASPEED BMC SoC's 'GFX' display hardware, also called33 * the 'SOC Display Controller' in the datasheet. This driver runs on the ARM34 * based BMC systems, unlike the ast driver which runs on a host CPU and is for35 * a PCIe graphics device.36 *37 * The AST2500 supports a total of 3 output paths:38 *39 * 1. VGA output, the output target can choose either or both to the DAC40 * or DVO interface.41 *42 * 2. Graphics CRT output, the output target can choose either or both to43 * the DAC or DVO interface.44 *45 * 3. Video input from DVO, the video input can be used for video engine46 * capture or DAC display output.47 *48 * Output options are selected in SCU2C.49 *50 * The "VGA mode" device is the PCI attached controller. The "Graphics CRT"51 * is the ARM's internal display controller.52 *53 * The driver only supports a simple configuration consisting of a 40MHz54 * pixel clock, fixed by hardware limitations, and the VGA output path.55 *56 * The driver was written with the 'AST2500 Software Programming Guide' v17,57 * which is available under NDA from ASPEED.58 */59 60struct aspeed_gfx_config {61 u32 dac_reg; /* DAC register in SCU */62 u32 int_clear_reg; /* Interrupt clear register */63 u32 vga_scratch_reg; /* VGA scratch register in SCU */64 u32 throd_val; /* Default Threshold Seting */65 u32 scan_line_max; /* Max memory size of one scan line */66};67 68static const struct aspeed_gfx_config ast2400_config = {69 .dac_reg = 0x2c,70 .int_clear_reg = 0x60,71 .vga_scratch_reg = 0x50,72 .throd_val = CRT_THROD_LOW(0x1e) | CRT_THROD_HIGH(0x12),73 .scan_line_max = 64,74};75 76static const struct aspeed_gfx_config ast2500_config = {77 .dac_reg = 0x2c,78 .int_clear_reg = 0x60,79 .vga_scratch_reg = 0x50,80 .throd_val = CRT_THROD_LOW(0x24) | CRT_THROD_HIGH(0x3c),81 .scan_line_max = 128,82};83 84static const struct aspeed_gfx_config ast2600_config = {85 .dac_reg = 0xc0,86 .int_clear_reg = 0x68,87 .vga_scratch_reg = 0x50,88 .throd_val = CRT_THROD_LOW(0x50) | CRT_THROD_HIGH(0x70),89 .scan_line_max = 128,90};91 92static const struct of_device_id aspeed_gfx_match[] = {93 { .compatible = "aspeed,ast2400-gfx", .data = &ast2400_config },94 { .compatible = "aspeed,ast2500-gfx", .data = &ast2500_config },95 { .compatible = "aspeed,ast2600-gfx", .data = &ast2600_config },96 { },97};98MODULE_DEVICE_TABLE(of, aspeed_gfx_match);99 100static const struct drm_mode_config_funcs aspeed_gfx_mode_config_funcs = {101 .fb_create = drm_gem_fb_create,102 .atomic_check = drm_atomic_helper_check,103 .atomic_commit = drm_atomic_helper_commit,104};105 106static int aspeed_gfx_setup_mode_config(struct drm_device *drm)107{108 int ret;109 110 ret = drmm_mode_config_init(drm);111 if (ret)112 return ret;113 114 drm->mode_config.min_width = 0;115 drm->mode_config.min_height = 0;116 drm->mode_config.max_width = 800;117 drm->mode_config.max_height = 600;118 drm->mode_config.funcs = &aspeed_gfx_mode_config_funcs;119 120 return ret;121}122 123static irqreturn_t aspeed_gfx_irq_handler(int irq, void *data)124{125 struct drm_device *drm = data;126 struct aspeed_gfx *priv = to_aspeed_gfx(drm);127 u32 reg;128 129 reg = readl(priv->base + CRT_CTRL1);130 131 if (reg & CRT_CTRL_VERTICAL_INTR_STS) {132 drm_crtc_handle_vblank(&priv->pipe.crtc);133 writel(reg, priv->base + priv->int_clr_reg);134 return IRQ_HANDLED;135 }136 137 return IRQ_NONE;138}139 140static int aspeed_gfx_load(struct drm_device *drm)141{142 struct platform_device *pdev = to_platform_device(drm->dev);143 struct aspeed_gfx *priv = to_aspeed_gfx(drm);144 struct device_node *np = pdev->dev.of_node;145 const struct aspeed_gfx_config *config;146 struct resource *res;147 int ret;148 149 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);150 priv->base = devm_ioremap_resource(drm->dev, res);151 if (IS_ERR(priv->base))152 return PTR_ERR(priv->base);153 154 config = device_get_match_data(&pdev->dev);155 if (!config)156 return -EINVAL;157 158 priv->dac_reg = config->dac_reg;159 priv->int_clr_reg = config->int_clear_reg;160 priv->vga_scratch_reg = config->vga_scratch_reg;161 priv->throd_val = config->throd_val;162 priv->scan_line_max = config->scan_line_max;163 164 priv->scu = syscon_regmap_lookup_by_phandle(np, "syscon");165 if (IS_ERR(priv->scu)) {166 priv->scu = syscon_regmap_lookup_by_compatible("aspeed,ast2500-scu");167 if (IS_ERR(priv->scu)) {168 dev_err(&pdev->dev, "failed to find SCU regmap\n");169 return PTR_ERR(priv->scu);170 }171 }172 173 ret = of_reserved_mem_device_init(drm->dev);174 if (ret) {175 dev_err(&pdev->dev,176 "failed to initialize reserved mem: %d\n", ret);177 return ret;178 }179 180 ret = dma_set_mask_and_coherent(drm->dev, DMA_BIT_MASK(32));181 if (ret) {182 dev_err(&pdev->dev, "failed to set DMA mask: %d\n", ret);183 return ret;184 }185 186 priv->rst = devm_reset_control_get_exclusive(&pdev->dev, NULL);187 if (IS_ERR(priv->rst)) {188 dev_err(&pdev->dev,189 "missing or invalid reset controller device tree entry");190 return PTR_ERR(priv->rst);191 }192 reset_control_deassert(priv->rst);193 194 priv->clk = devm_clk_get(drm->dev, NULL);195 if (IS_ERR(priv->clk)) {196 dev_err(&pdev->dev,197 "missing or invalid clk device tree entry");198 return PTR_ERR(priv->clk);199 }200 clk_prepare_enable(priv->clk);201 202 /* Sanitize control registers */203 writel(0, priv->base + CRT_CTRL1);204 writel(0, priv->base + CRT_CTRL2);205 206 ret = aspeed_gfx_setup_mode_config(drm);207 if (ret < 0)208 return ret;209 210 ret = drm_vblank_init(drm, 1);211 if (ret < 0) {212 dev_err(drm->dev, "Failed to initialise vblank\n");213 return ret;214 }215 216 ret = aspeed_gfx_create_output(drm);217 if (ret < 0) {218 dev_err(drm->dev, "Failed to create outputs\n");219 return ret;220 }221 222 ret = aspeed_gfx_create_pipe(drm);223 if (ret < 0) {224 dev_err(drm->dev, "Cannot setup simple display pipe\n");225 return ret;226 }227 228 ret = devm_request_irq(drm->dev, platform_get_irq(pdev, 0),229 aspeed_gfx_irq_handler, 0, "aspeed gfx", drm);230 if (ret < 0) {231 dev_err(drm->dev, "Failed to install IRQ handler\n");232 return ret;233 }234 235 drm_mode_config_reset(drm);236 237 return 0;238}239 240static void aspeed_gfx_unload(struct drm_device *drm)241{242 drm_kms_helper_poll_fini(drm);243}244 245DEFINE_DRM_GEM_DMA_FOPS(fops);246 247static const struct drm_driver aspeed_gfx_driver = {248 .driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,249 DRM_GEM_DMA_DRIVER_OPS,250 .fops = &fops,251 .name = "aspeed-gfx-drm",252 .desc = "ASPEED GFX DRM",253 .date = "20180319",254 .major = 1,255 .minor = 0,256};257 258static ssize_t dac_mux_store(struct device *dev, struct device_attribute *attr,259 const char *buf, size_t count)260{261 struct aspeed_gfx *priv = dev_get_drvdata(dev);262 u32 val;263 int rc;264 265 rc = kstrtou32(buf, 0, &val);266 if (rc)267 return rc;268 269 if (val > 3)270 return -EINVAL;271 272 rc = regmap_update_bits(priv->scu, priv->dac_reg, 0x30000, val << 16);273 if (rc < 0)274 return 0;275 276 return count;277}278 279static ssize_t dac_mux_show(struct device *dev, struct device_attribute *attr, char *buf)280{281 struct aspeed_gfx *priv = dev_get_drvdata(dev);282 u32 reg;283 int rc;284 285 rc = regmap_read(priv->scu, priv->dac_reg, ®);286 if (rc)287 return rc;288 289 return sprintf(buf, "%u\n", (reg >> 16) & 0x3);290}291static DEVICE_ATTR_RW(dac_mux);292 293static ssize_t294vga_pw_show(struct device *dev, struct device_attribute *attr, char *buf)295{296 struct aspeed_gfx *priv = dev_get_drvdata(dev);297 u32 reg;298 int rc;299 300 rc = regmap_read(priv->scu, priv->vga_scratch_reg, ®);301 if (rc)302 return rc;303 304 return sprintf(buf, "%u\n", reg);305}306static DEVICE_ATTR_RO(vga_pw);307 308static struct attribute *aspeed_sysfs_entries[] = {309 &dev_attr_vga_pw.attr,310 &dev_attr_dac_mux.attr,311 NULL,312};313 314static struct attribute_group aspeed_sysfs_attr_group = {315 .attrs = aspeed_sysfs_entries,316};317 318static int aspeed_gfx_probe(struct platform_device *pdev)319{320 struct aspeed_gfx *priv;321 int ret;322 323 priv = devm_drm_dev_alloc(&pdev->dev, &aspeed_gfx_driver,324 struct aspeed_gfx, drm);325 if (IS_ERR(priv))326 return PTR_ERR(priv);327 328 ret = aspeed_gfx_load(&priv->drm);329 if (ret)330 return ret;331 332 platform_set_drvdata(pdev, priv);333 334 ret = sysfs_create_group(&pdev->dev.kobj, &aspeed_sysfs_attr_group);335 if (ret)336 return ret;337 338 ret = drm_dev_register(&priv->drm, 0);339 if (ret)340 goto err_unload;341 342 drm_fbdev_dma_setup(&priv->drm, 32);343 return 0;344 345err_unload:346 sysfs_remove_group(&pdev->dev.kobj, &aspeed_sysfs_attr_group);347 aspeed_gfx_unload(&priv->drm);348 349 return ret;350}351 352static void aspeed_gfx_remove(struct platform_device *pdev)353{354 struct drm_device *drm = platform_get_drvdata(pdev);355 356 sysfs_remove_group(&pdev->dev.kobj, &aspeed_sysfs_attr_group);357 drm_dev_unregister(drm);358 aspeed_gfx_unload(drm);359 drm_atomic_helper_shutdown(drm);360}361 362static void aspeed_gfx_shutdown(struct platform_device *pdev)363{364 drm_atomic_helper_shutdown(platform_get_drvdata(pdev));365}366 367static struct platform_driver aspeed_gfx_platform_driver = {368 .probe = aspeed_gfx_probe,369 .remove_new = aspeed_gfx_remove,370 .shutdown = aspeed_gfx_shutdown,371 .driver = {372 .name = "aspeed_gfx",373 .of_match_table = aspeed_gfx_match,374 },375};376 377drm_module_platform_driver(aspeed_gfx_platform_driver);378 379MODULE_AUTHOR("Joel Stanley <joel@jms.id.au>");380MODULE_DESCRIPTION("ASPEED BMC DRM/KMS driver");381MODULE_LICENSE("GPL");382