1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _SCREEN_INFO_H 3 #define _SCREEN_INFO_H 4 5 #include <uapi/linux/screen_info.h> 6 7 #include <linux/bits.h> 8 9 /** 10 * SCREEN_INFO_MAX_RESOURCES - maximum number of resources per screen_info 11 */ 12 #define SCREEN_INFO_MAX_RESOURCES 3 13 14 struct pci_dev; 15 struct pixel_format; 16 struct resource; 17 18 static inline bool __screen_info_has_lfb(unsigned int type) 19 { 20 return (type == VIDEO_TYPE_VLFB) || (type == VIDEO_TYPE_EFI); 21 } 22 23 static inline u64 __screen_info_lfb_base(const struct screen_info *si) 24 { 25 u64 lfb_base = si->lfb_base; 26 27 if (si->capabilities & VIDEO_CAPABILITY_64BIT_BASE) 28 lfb_base |= (u64)si->ext_lfb_base << 32; 29 30 return lfb_base; 31 } 32 33 static inline void __screen_info_set_lfb_base(struct screen_info *si, u64 lfb_base) 34 { 35 si->lfb_base = lfb_base & GENMASK_ULL(31, 0); 36 si->ext_lfb_base = (lfb_base & GENMASK_ULL(63, 32)) >> 32; 37 38 if (si->ext_lfb_base) 39 si->capabilities |= VIDEO_CAPABILITY_64BIT_BASE; 40 else 41 si->capabilities &= ~VIDEO_CAPABILITY_64BIT_BASE; 42 } 43 44 static inline u64 __screen_info_lfb_size(const struct screen_info *si, unsigned int type) 45 { 46 u64 lfb_size = si->lfb_size; 47 48 if (type == VIDEO_TYPE_VLFB) 49 lfb_size <<= 16; 50 return lfb_size; 51 } 52 53 static inline bool __screen_info_vbe_mode_nonvga(const struct screen_info *si) 54 { 55 /* 56 * VESA modes typically run on VGA hardware. Set bit 5 signals that this 57 * is not the case. Drivers can then not make use of VGA resources. See 58 * Sec 4.4 of the VBE 2.0 spec. 59 */ 60 return si->vesa_attributes & BIT(5); 61 } 62 63 static inline unsigned int __screen_info_video_type(unsigned int type) 64 { 65 switch (type) { 66 case VIDEO_TYPE_MDA: 67 case VIDEO_TYPE_CGA: 68 case VIDEO_TYPE_EGAM: 69 case VIDEO_TYPE_EGAC: 70 case VIDEO_TYPE_VGAC: 71 case VIDEO_TYPE_VLFB: 72 case VIDEO_TYPE_PICA_S3: 73 case VIDEO_TYPE_MIPS_G364: 74 case VIDEO_TYPE_SGI: 75 case VIDEO_TYPE_TGAC: 76 case VIDEO_TYPE_SUN: 77 case VIDEO_TYPE_SUNPCI: 78 case VIDEO_TYPE_PMAC: 79 case VIDEO_TYPE_EFI: 80 return type; 81 default: 82 return 0; 83 } 84 } 85 86 /** 87 * screen_info_video_type() - Decodes the video type from struct screen_info 88 * @si: an instance of struct screen_info 89 * 90 * Returns: 91 * A VIDEO_TYPE_ constant representing si's type of video display, or 0 otherwise. 92 */ 93 static inline unsigned int screen_info_video_type(const struct screen_info *si) 94 { 95 unsigned int type; 96 97 // check if display output is on 98 if (!si->orig_video_isVGA) 99 return 0; 100 101 // check for a known VIDEO_TYPE_ constant 102 type = __screen_info_video_type(si->orig_video_isVGA); 103 if (type) 104 return si->orig_video_isVGA; 105 106 // check if text mode has been initialized 107 if (!si->orig_video_lines || !si->orig_video_cols) 108 return 0; 109 110 // 80x25 text, mono 111 if (si->orig_video_mode == 0x07) { 112 if ((si->orig_video_ega_bx & 0xff) != 0x10) 113 return VIDEO_TYPE_EGAM; 114 else 115 return VIDEO_TYPE_MDA; 116 } 117 118 // EGA/VGA, 16 colors 119 if ((si->orig_video_ega_bx & 0xff) != 0x10) { 120 if (si->orig_video_isVGA) 121 return VIDEO_TYPE_VGAC; 122 else 123 return VIDEO_TYPE_EGAC; 124 } 125 126 // the rest... 127 return VIDEO_TYPE_CGA; 128 } 129 130 static inline u32 __screen_info_vesapm_info_base(const struct screen_info *si) 131 { 132 if (si->vesapm_seg < 0xc000) 133 return 0; 134 return (si->vesapm_seg << 4) + si->vesapm_off; 135 } 136 137 ssize_t screen_info_resources(const struct screen_info *si, struct resource *r, size_t num); 138 139 u32 __screen_info_lfb_bits_per_pixel(const struct screen_info *si); 140 int screen_info_pixel_format(const struct screen_info *si, struct pixel_format *f); 141 142 #if defined(CONFIG_PCI) 143 void screen_info_apply_fixups(void); 144 struct pci_dev *screen_info_pci_dev(const struct screen_info *si); 145 #else 146 static inline void screen_info_apply_fixups(void) 147 { } 148 static inline struct pci_dev *screen_info_pci_dev(const struct screen_info *si) 149 { 150 return NULL; 151 } 152 #endif 153 154 extern struct screen_info screen_info; 155 156 #endif /* _SCREEN_INFO_H */ 157