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1// SPDX-License-Identifier: GPL-2.02 3#include <linux/export.h>4#include <linux/ioport.h>5#include <linux/screen_info.h>6#include <linux/string.h>7 8static void resource_init_named(struct resource *r,9 resource_size_t start, resource_size_t size,10 const char *name, unsigned int flags)11{12 memset(r, 0, sizeof(*r));13 14 r->start = start;15 r->end = start + size - 1;16 r->name = name;17 r->flags = flags;18}19 20static void resource_init_io_named(struct resource *r,21 resource_size_t start, resource_size_t size,22 const char *name)23{24 resource_init_named(r, start, size, name, IORESOURCE_IO);25}26 27static void resource_init_mem_named(struct resource *r,28 resource_size_t start, resource_size_t size,29 const char *name)30{31 resource_init_named(r, start, size, name, IORESOURCE_MEM);32}33 34static inline bool __screen_info_has_ega_gfx(unsigned int mode)35{36 switch (mode) {37 case 0x0d: /* 320x200-4 */38 case 0x0e: /* 640x200-4 */39 case 0x0f: /* 640x350-1 */40 case 0x10: /* 640x350-4 */41 return true;42 default:43 return false;44 }45}46 47static inline bool __screen_info_has_vga_gfx(unsigned int mode)48{49 switch (mode) {50 case 0x10: /* 640x480-1 */51 case 0x12: /* 640x480-4 */52 case 0x13: /* 320-200-8 */53 case 0x6a: /* 800x600-4 (VESA) */54 return true;55 default:56 return __screen_info_has_ega_gfx(mode);57 }58}59 60/**61 * screen_info_resources() - Get resources from screen_info structure62 * @si: the screen_info63 * @r: pointer to an array of resource structures64 * @num: number of elements in @r:65 *66 * Returns:67 * The number of resources stored in @r on success, or a negative errno code otherwise.68 *69 * A call to screen_info_resources() returns the resources consumed by the70 * screen_info's device or framebuffer. The result is stored in the caller-supplied71 * array @r with up to @num elements. The function returns the number of72 * initialized elements.73 */74ssize_t screen_info_resources(const struct screen_info *si, struct resource *r, size_t num)75{76 struct resource *pos = r;77 unsigned int type = screen_info_video_type(si);78 u64 base, size;79 80 switch (type) {81 case VIDEO_TYPE_MDA:82 if (num > 0)83 resource_init_io_named(pos++, 0x3b0, 12, "mda");84 if (num > 1)85 resource_init_io_named(pos++, 0x3bf, 0x01, "mda");86 if (num > 2)87 resource_init_mem_named(pos++, 0xb0000, 0x2000, "mda");88 break;89 case VIDEO_TYPE_CGA:90 if (num > 0)91 resource_init_io_named(pos++, 0x3d4, 0x02, "cga");92 if (num > 1)93 resource_init_mem_named(pos++, 0xb8000, 0x2000, "cga");94 break;95 case VIDEO_TYPE_EGAM:96 if (num > 0)97 resource_init_io_named(pos++, 0x3bf, 0x10, "ega");98 if (num > 1)99 resource_init_mem_named(pos++, 0xb0000, 0x8000, "ega");100 break;101 case VIDEO_TYPE_EGAC:102 if (num > 0)103 resource_init_io_named(pos++, 0x3c0, 0x20, "ega");104 if (num > 1) {105 if (__screen_info_has_ega_gfx(si->orig_video_mode))106 resource_init_mem_named(pos++, 0xa0000, 0x10000, "ega");107 else108 resource_init_mem_named(pos++, 0xb8000, 0x8000, "ega");109 }110 break;111 case VIDEO_TYPE_VGAC:112 if (num > 0)113 resource_init_io_named(pos++, 0x3c0, 0x20, "vga+");114 if (num > 1) {115 if (__screen_info_has_vga_gfx(si->orig_video_mode))116 resource_init_mem_named(pos++, 0xa0000, 0x10000, "vga+");117 else118 resource_init_mem_named(pos++, 0xb8000, 0x8000, "vga+");119 }120 break;121 case VIDEO_TYPE_VLFB:122 case VIDEO_TYPE_EFI:123 base = __screen_info_lfb_base(si);124 if (!base)125 break;126 size = __screen_info_lfb_size(si, type);127 if (!size)128 break;129 if (num > 0)130 resource_init_mem_named(pos++, base, size, "lfb");131 break;132 case VIDEO_TYPE_PICA_S3:133 case VIDEO_TYPE_MIPS_G364:134 case VIDEO_TYPE_SGI:135 case VIDEO_TYPE_TGAC:136 case VIDEO_TYPE_SUN:137 case VIDEO_TYPE_SUNPCI:138 case VIDEO_TYPE_PMAC:139 default:140 /* not supported */141 return -EINVAL;142 }143 144 return pos - r;145}146EXPORT_SYMBOL(screen_info_resources);147