/* SPDX-License-Identifier: GPL-2.0-or-later */ #include <pc80/vga.h> #include <pc80/vga_io.h> #include <string.h> #include "vga.h" /* * pci io enable should've happened before */ void vga_io_init(void) { vga_enable_mask(0x01, 0x01); /* cr io is at 0x3D4/0x3D5 */ vga_misc_mask(0x01, 0x01); /* clear cr0-7 protection */ vga_cr_mask(0x11, 0x00, 0x80); } /* * */ static void vga_fb_init(void) { vga_sr_write(0x02, 0x03); vga_sr_write(0x03, 0x00); vga_sr_write(0x04, 0x02); /* access all 256kB */ vga_gr_write(0x00, 0x00); vga_gr_write(0x01, 0x00); vga_gr_write(0x02, 0x00); vga_gr_write(0x03, 0x00); vga_gr_write(0x04, 0x00); vga_gr_write(0x05, 0x10); vga_gr_write(0x06, 0x0E); /* map at 0xB8000 */ vga_gr_write(0x07, 0x00); vga_gr_write(0x08, 0xFF); /* o/e enable: RAM enable */ vga_misc_mask(0x22, 0x22); } /* * */ static void vga_fb_clear(void) { memset((void *)VGA_FB, 0x00, 0x8000); } /* * */ static void vga_palette_init(void) { unsigned int i; /* set up attribute registers */ for (i = 0; i < 0x10; i++) vga_ar_write(i, i); vga_ar_write(0x10, 0x0c); vga_ar_write(0x11, 0x00); vga_ar_write(0x12, 0x0F); vga_ar_write(0x13, 0x08); vga_ar_write(0x14, 0x00); vga_palette_disable(); /* load actual palette */ vga_dac_mask_write(0xFF); for (i = 0; i < 0x100; i++) { vga_dac_write_address(i); vga_dac_data_write(default_vga_palette[i].red); vga_dac_data_write(default_vga_palette[i].green); vga_dac_data_write(default_vga_palette[i].blue); } } /* * */ static void vga_mode_set(int hdisplay, int hblankstart, int hsyncstart, int hsyncend, int hblankend, int htotal, int vdisplay, int vblankstart, int vsyncstart, int vsyncend, int vblankend, int vtotal, int stride) { /* htotal: 2080 */ htotal /= 8; htotal -= 5; vga_cr_write(0x00, htotal); /* hdisplay: 2048 */ hdisplay /= 8; hdisplay -= 1; vga_cr_write(0x01, hdisplay); /* hblankstart: 2048 */ hblankstart /= 8; hblankstart -= 1; vga_cr_write(0x02, hblankstart); /* hblankend: hblankstart + 512 */ hblankend /= 8; hblankend -= 1; vga_cr_mask(0x03, hblankend, 0x1F); vga_cr_mask(0x05, hblankend << 2, 0x80); /* hsyncstart: 255 * 8: 2040 */ vga_cr_write(0x04, hsyncstart / 8); /* hsyncend: hsyncstart + 255 */ vga_cr_mask(0x05, hsyncend / 8, 0x1F); /* vtotal: 1025 */ vtotal -= 2; vga_cr_write(0x06, vtotal); vga_cr_mask(0x07, vtotal >> 8, 0x01); vga_cr_mask(0x07, vtotal >> 4, 0x20); /* vdisplay: 1024 */ vdisplay -= 1; vga_cr_write(0x12, vdisplay); vga_cr_mask(0x07, vdisplay >> 7, 0x02); vga_cr_mask(0x07, vdisplay >> 3, 0x40); /* vblankstart: 1024 */ vblankstart -= 1; vga_cr_write(0x15, vblankstart); vga_cr_mask(0x07, vblankstart >> 5, 0x08); vga_cr_mask(0x09, vblankstart >> 4, 0x20); /* vblankend: vblankstart + 256 */ vblankend -= 1; vga_cr_write(0x16, vblankend); /* vsyncstart: 1023 */ vga_cr_write(0x10, vsyncstart); vga_cr_mask(0x07, vsyncstart >> 6, 0x04); vga_cr_mask(0x07, vsyncstart >> 2, 0x80); /* vsyncend: vsyncstart + 16 */ vga_cr_mask(0x11, vsyncend, 0x0F); /* stride */ vga_cr_write(0x13, stride / 8); /* line compare */ vga_cr_write(0x18, 0xFF); vga_cr_mask(0x07, 0x10, 0x10); vga_cr_mask(0x09, 0x40, 0x40); vga_misc_mask(0x44, 0xCC); /* set up clock: 27mhz and h/vsync */ vga_cr_mask(0x09, 0x00, 0x80); /* disable doublescan */ } static void vga_font_8x16_load(void) { unsigned char *p; int i, j; unsigned char sr2, sr4, gr5, gr6; #define height 16 #define count 256 sr2 = vga_sr_read(0x02); sr4 = vga_sr_read(0x04); gr5 = vga_gr_read(0x05); gr6 = vga_gr_read(0x06); /* disable odd/even */ vga_sr_mask(0x04, 0x04, 0x04); vga_gr_mask(0x05, 0x00, 0x10); vga_gr_mask(0x06, 0x00, 0x02); /* plane 2 */ vga_sr_write(0x02, 0x04); p = (unsigned char *) VGA_FB; for (i = 0; i < count; i++) { for (j = 0; j < 32; j++) { if (j < height) *p = vga_font_8x16[i][j]; else *p = 0x00; p++; } } vga_gr_write(0x06, gr6); vga_gr_write(0x05, gr5); vga_sr_write(0x04, sr4); vga_sr_write(0x02, sr2); /* set up font size */ vga_cr_mask(0x09, 16 - 1, 0x1F); } /* * */ void vga_cursor_enable(int enable) { if (enable) vga_cr_mask(0x0A, 0x00, 0x20); else vga_cr_mask(0x0A, 0x20, 0x20); } /* * */ void vga_cursor_reset(void) { vga_cr_write(0x0A, 0x2E); vga_cr_write(0x0B, 0x0E); vga_cr_write(0x0E, 0x00); vga_cr_write(0x0F, 0x00); } /* * */ void vga_cursor_set(unsigned int line, unsigned int character) { unsigned int offset = (80 * line + character) & 0xFFFF; vga_cr_write(0x0A, 0x0E); vga_cr_write(0x0B, 0x0E); vga_cr_write(0x0E, offset >> 8); vga_cr_write(0x0F, offset & 0xFF); } /* * */ void vga_frame_set(unsigned int line, unsigned int character) { unsigned int offset = (80 * line + character) & 0xFFFF; vga_cr_write(0x0C, offset >> 8); vga_cr_write(0x0D, offset & 0xFF); } /* * simply fills a line with the given string. */ void vga_line_write(unsigned int line, const char *string) { unsigned short *p = (unsigned short *) VGA_FB + (80 * line); int i, len = strlen(string); for (i = 0; i < 80; i++) { if (i < len) p[i] = 0x0F00 | string[i]; else p[i] = 0x0F00; } } /* * set up everything to get a basic 80x25 textmode. */ void vga_textmode_init(void) { vga_sr_write(0x00, 0x01); /* clear reset */ vga_sr_write(0x01, 0x00); /* set up cr */ vga_cr_mask(0x03, 0x80, 0xE0); vga_cr_mask(0x05, 0x00, 0x60); vga_cr_write(0x08, 0x00); vga_cr_write(0x14, 0x00); /* */ vga_cr_write(0x17, 0x23); vga_palette_init(); vga_mode_set(640, 648, 680, 776, 792, 800, 400, 407, 412, 414, 442, 449, 320); vga_cursor_reset(); vga_frame_set(0, 0); vga_fb_init(); vga_fb_clear(); vga_font_8x16_load(); vga_sr_mask(0x00, 0x02, 0x02); /* take us out of reset */ vga_cr_mask(0x17, 0x80, 0x80); /* sync! */ }