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1// SPDX-License-Identifier: GPL-2.0-only2/*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 22enum {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 << 135};36 37struct 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 48static 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 64static 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 71static int72goldfish_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 88static 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 116static 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 129static 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 148static 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 163static 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 174static 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 267err_register_framebuffer_failed:268 free_irq(fb->irq, fb);269err_request_irq_failed:270err_fb_set_var_failed:271 dma_free_coherent(&pdev->dev, framesize,272 (void *)fb->fb.screen_base,273 fb->fb.fix.smem_start);274err_alloc_screen_base_failed:275err_no_irq:276 iounmap(fb->reg_base);277err_no_io_base:278 kfree(fb);279err_fb_alloc_failed:280 return ret;281}282 283static 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 298static const struct of_device_id goldfish_fb_of_match[] = {299 { .compatible = "google,goldfish-fb", },300 {},301};302MODULE_DEVICE_TABLE(of, goldfish_fb_of_match);303 304#ifdef CONFIG_ACPI305static const struct acpi_device_id goldfish_fb_acpi_match[] = {306 { "GFSH0004", 0 },307 { },308};309MODULE_DEVICE_TABLE(acpi, goldfish_fb_acpi_match);310#endif311 312static struct platform_driver goldfish_fb_driver = {313 .probe = goldfish_fb_probe,314 .remove = 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 322module_platform_driver(goldfish_fb_driver);323 324MODULE_DESCRIPTION("Goldfish Virtual Platform Framebuffer driver");325MODULE_LICENSE("GPL v2");326