1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2007 Google, Inc. 4 * Copyright (C) 2012 Intel, Inc. 5 */ 6 7 #include <linux/module.h> 8 #include <linux/kernel.h> 9 #include <linux/dma-mapping.h> 10 #include <linux/errno.h> 11 #include <linux/string.h> 12 #include <linux/slab.h> 13 #include <linux/delay.h> 14 #include <linux/mm.h> 15 #include <linux/fb.h> 16 #include <linux/init.h> 17 #include <linux/interrupt.h> 18 #include <linux/ioport.h> 19 #include <linux/platform_device.h> 20 #include <linux/acpi.h> 21 22 enum { 23 FB_GET_WIDTH = 0x00, 24 FB_GET_HEIGHT = 0x04, 25 FB_INT_STATUS = 0x08, 26 FB_INT_ENABLE = 0x0c, 27 FB_SET_BASE = 0x10, 28 FB_SET_ROTATION = 0x14, 29 FB_SET_BLANK = 0x18, 30 FB_GET_PHYS_WIDTH = 0x1c, 31 FB_GET_PHYS_HEIGHT = 0x20, 32 33 FB_INT_VSYNC = 1U << 0, 34 FB_INT_BASE_UPDATE_DONE = 1U << 1 35 }; 36 37 struct goldfish_fb { 38 void __iomem *reg_base; 39 int irq; 40 spinlock_t lock; 41 wait_queue_head_t wait; 42 int base_update_count; 43 int rotation; 44 struct fb_info fb; 45 u32 cmap[16]; 46 }; 47 48 static irqreturn_t goldfish_fb_interrupt(int irq, void *dev_id) 49 { 50 unsigned long irq_flags; 51 struct goldfish_fb *fb = dev_id; 52 u32 status; 53 54 spin_lock_irqsave(&fb->lock, irq_flags); 55 status = readl(fb->reg_base + FB_INT_STATUS); 56 if (status & FB_INT_BASE_UPDATE_DONE) { 57 fb->base_update_count++; 58 wake_up(&fb->wait); 59 } 60 spin_unlock_irqrestore(&fb->lock, irq_flags); 61 return status ? IRQ_HANDLED : IRQ_NONE; 62 } 63 64 static inline u32 convert_bitfield(int val, struct fb_bitfield *bf) 65 { 66 unsigned int mask = (1 << bf->length) - 1; 67 68 return (val >> (16 - bf->length) & mask) << bf->offset; 69 } 70 71 static int 72 goldfish_fb_setcolreg(unsigned int regno, unsigned int red, unsigned int green, 73 unsigned int blue, unsigned int transp, struct fb_info *info) 74 { 75 struct goldfish_fb *fb = container_of(info, struct goldfish_fb, fb); 76 77 if (regno < 16) { 78 fb->cmap[regno] = convert_bitfield(transp, &fb->fb.var.transp) | 79 convert_bitfield(blue, &fb->fb.var.blue) | 80 convert_bitfield(green, &fb->fb.var.green) | 81 convert_bitfield(red, &fb->fb.var.red); 82 return 0; 83 } else { 84 return 1; 85 } 86 } 87 88 static int goldfish_fb_check_var(struct fb_var_screeninfo *var, 89 struct fb_info *info) 90 { 91 if ((var->rotate & 1) != (info->var.rotate & 1)) { 92 if ((var->xres != info->var.yres) || 93 (var->yres != info->var.xres) || 94 (var->xres_virtual != info->var.yres) || 95 (var->yres_virtual > info->var.xres * 2) || 96 (var->yres_virtual < info->var.xres)) { 97 return -EINVAL; 98 } 99 } else { 100 if ((var->xres != info->var.xres) || 101 (var->yres != info->var.yres) || 102 (var->xres_virtual != info->var.xres) || 103 (var->yres_virtual > info->var.yres * 2) || 104 (var->yres_virtual < info->var.yres)) { 105 return -EINVAL; 106 } 107 } 108 if ((var->xoffset != info->var.xoffset) || 109 (var->bits_per_pixel != info->var.bits_per_pixel) || 110 (var->grayscale != info->var.grayscale)) { 111 return -EINVAL; 112 } 113 return 0; 114 } 115 116 static int goldfish_fb_set_par(struct fb_info *info) 117 { 118 struct goldfish_fb *fb = container_of(info, struct goldfish_fb, fb); 119 120 if (fb->rotation != fb->fb.var.rotate) { 121 info->fix.line_length = info->var.xres * 2; 122 fb->rotation = fb->fb.var.rotate; 123 writel(fb->rotation, fb->reg_base + FB_SET_ROTATION); 124 } 125 return 0; 126 } 127 128 129 static int goldfish_fb_pan_display(struct fb_var_screeninfo *var, 130 struct fb_info *info) 131 { 132 unsigned long irq_flags; 133 int base_update_count; 134 struct goldfish_fb *fb = container_of(info, struct goldfish_fb, fb); 135 136 spin_lock_irqsave(&fb->lock, irq_flags); 137 base_update_count = fb->base_update_count; 138 writel(fb->fb.fix.smem_start + fb->fb.var.xres * 2 * var->yoffset, 139 fb->reg_base + FB_SET_BASE); 140 spin_unlock_irqrestore(&fb->lock, irq_flags); 141 wait_event_timeout(fb->wait, 142 fb->base_update_count != base_update_count, HZ / 15); 143 if (fb->base_update_count == base_update_count) 144 pr_err("%s: timeout waiting for base update\n", __func__); 145 return 0; 146 } 147 148 static int goldfish_fb_blank(int blank, struct fb_info *info) 149 { 150 struct goldfish_fb *fb = container_of(info, struct goldfish_fb, fb); 151 152 switch (blank) { 153 case FB_BLANK_NORMAL: 154 writel(1, fb->reg_base + FB_SET_BLANK); 155 break; 156 case FB_BLANK_UNBLANK: 157 writel(0, fb->reg_base + FB_SET_BLANK); 158 break; 159 } 160 return 0; 161 } 162 163 static const struct fb_ops goldfish_fb_ops = { 164 .owner = THIS_MODULE, 165 FB_DEFAULT_IOMEM_OPS, 166 .fb_check_var = goldfish_fb_check_var, 167 .fb_set_par = goldfish_fb_set_par, 168 .fb_setcolreg = goldfish_fb_setcolreg, 169 .fb_pan_display = goldfish_fb_pan_display, 170 .fb_blank = goldfish_fb_blank, 171 }; 172 173 174 static int goldfish_fb_probe(struct platform_device *pdev) 175 { 176 int ret; 177 struct resource *r; 178 struct goldfish_fb *fb; 179 size_t framesize; 180 u32 width, height; 181 dma_addr_t fbpaddr; 182 183 fb = kzalloc(sizeof(*fb), GFP_KERNEL); 184 if (fb == NULL) { 185 ret = -ENOMEM; 186 goto err_fb_alloc_failed; 187 } 188 spin_lock_init(&fb->lock); 189 init_waitqueue_head(&fb->wait); 190 platform_set_drvdata(pdev, fb); 191 192 r = platform_get_resource(pdev, IORESOURCE_MEM, 0); 193 if (r == NULL) { 194 ret = -ENODEV; 195 goto err_no_io_base; 196 } 197 fb->reg_base = ioremap(r->start, PAGE_SIZE); 198 if (fb->reg_base == NULL) { 199 ret = -ENOMEM; 200 goto err_no_io_base; 201 } 202 203 fb->irq = platform_get_irq(pdev, 0); 204 if (fb->irq < 0) { 205 ret = fb->irq; 206 goto err_no_irq; 207 } 208 209 width = readl(fb->reg_base + FB_GET_WIDTH); 210 height = readl(fb->reg_base + FB_GET_HEIGHT); 211 212 fb->fb.fbops = &goldfish_fb_ops; 213 fb->fb.pseudo_palette = fb->cmap; 214 fb->fb.fix.type = FB_TYPE_PACKED_PIXELS; 215 fb->fb.fix.visual = FB_VISUAL_TRUECOLOR; 216 fb->fb.fix.line_length = width * 2; 217 fb->fb.fix.accel = FB_ACCEL_NONE; 218 fb->fb.fix.ypanstep = 1; 219 220 fb->fb.var.xres = width; 221 fb->fb.var.yres = height; 222 fb->fb.var.xres_virtual = width; 223 fb->fb.var.yres_virtual = height * 2; 224 fb->fb.var.bits_per_pixel = 16; 225 fb->fb.var.activate = FB_ACTIVATE_NOW; 226 fb->fb.var.height = readl(fb->reg_base + FB_GET_PHYS_HEIGHT); 227 fb->fb.var.width = readl(fb->reg_base + FB_GET_PHYS_WIDTH); 228 fb->fb.var.pixclock = 0; 229 230 fb->fb.var.red.offset = 11; 231 fb->fb.var.red.length = 5; 232 fb->fb.var.green.offset = 5; 233 fb->fb.var.green.length = 6; 234 fb->fb.var.blue.offset = 0; 235 fb->fb.var.blue.length = 5; 236 237 framesize = width * height * 2 * 2; 238 fb->fb.screen_base = (char __force __iomem *)dma_alloc_coherent( 239 &pdev->dev, framesize, 240 &fbpaddr, GFP_KERNEL); 241 pr_debug("allocating frame buffer %d * %d, got %p\n", 242 width, height, fb->fb.screen_base); 243 if (fb->fb.screen_base == NULL) { 244 ret = -ENOMEM; 245 goto err_alloc_screen_base_failed; 246 } 247 fb->fb.fix.smem_start = fbpaddr; 248 fb->fb.fix.smem_len = framesize; 249 250 ret = fb_set_var(&fb->fb, &fb->fb.var); 251 if (ret) 252 goto err_fb_set_var_failed; 253 254 ret = request_irq(fb->irq, goldfish_fb_interrupt, IRQF_SHARED, 255 pdev->name, fb); 256 if (ret) 257 goto err_request_irq_failed; 258 259 writel(FB_INT_BASE_UPDATE_DONE, fb->reg_base + FB_INT_ENABLE); 260 goldfish_fb_pan_display(&fb->fb.var, &fb->fb); /* updates base */ 261 262 ret = register_framebuffer(&fb->fb); 263 if (ret) 264 goto err_register_framebuffer_failed; 265 return 0; 266 267 err_register_framebuffer_failed: 268 free_irq(fb->irq, fb); 269 err_request_irq_failed: 270 err_fb_set_var_failed: 271 dma_free_coherent(&pdev->dev, framesize, 272 (void *)fb->fb.screen_base, 273 fb->fb.fix.smem_start); 274 err_alloc_screen_base_failed: 275 err_no_irq: 276 iounmap(fb->reg_base); 277 err_no_io_base: 278 kfree(fb); 279 err_fb_alloc_failed: 280 return ret; 281 } 282 283 static void goldfish_fb_remove(struct platform_device *pdev) 284 { 285 size_t framesize; 286 struct goldfish_fb *fb = platform_get_drvdata(pdev); 287 288 framesize = fb->fb.var.xres_virtual * fb->fb.var.yres_virtual * 2; 289 unregister_framebuffer(&fb->fb); 290 free_irq(fb->irq, fb); 291 292 dma_free_coherent(&pdev->dev, framesize, (void *)fb->fb.screen_base, 293 fb->fb.fix.smem_start); 294 iounmap(fb->reg_base); 295 kfree(fb); 296 } 297 298 static const struct of_device_id goldfish_fb_of_match[] = { 299 { .compatible = "google,goldfish-fb", }, 300 {}, 301 }; 302 MODULE_DEVICE_TABLE(of, goldfish_fb_of_match); 303 304 #ifdef CONFIG_ACPI 305 static const struct acpi_device_id goldfish_fb_acpi_match[] = { 306 { "GFSH0004", 0 }, 307 { }, 308 }; 309 MODULE_DEVICE_TABLE(acpi, goldfish_fb_acpi_match); 310 #endif 311 312 static struct platform_driver goldfish_fb_driver = { 313 .probe = goldfish_fb_probe, 314 .remove_new = goldfish_fb_remove, 315 .driver = { 316 .name = "goldfish_fb", 317 .of_match_table = goldfish_fb_of_match, 318 .acpi_match_table = ACPI_PTR(goldfish_fb_acpi_match), 319 } 320 }; 321 322 module_platform_driver(goldfish_fb_driver); 323 324 MODULE_LICENSE("GPL v2"); 325