--- /dev/null
+// Code for manipulating VGA framebuffers.
+//
+// Copyright (C) 2009-2014 Kevin O'Connor <kevin@koconnor.net>
+// Copyright (C) 2001-2008 the LGPL VGABios developers Team
+//
+// This file may be distributed under the terms of the GNU LGPLv3 license.
+
+#include "biosvar.h" // GET_BDA
+#include "byteorder.h" // cpu_to_be16
+#include "output.h" // dprintf
+#include "stdvga.h" // stdvga_planar4_plane
+#include "string.h" // memset_far
+#include "vgabios.h" // vgafb_scroll
+#include "vgahw.h" // vgahw_get_linelength
+
+static inline void
+memmove_stride(u16 seg, void *dst, void *src, int copylen, int stride, int lines)
+{
+ if (src < dst) {
+ dst += stride * (lines - 1);
+ src += stride * (lines - 1);
+ stride = -stride;
+ }
+ for (; lines; lines--, dst+=stride, src+=stride)
+ memcpy_far(seg, dst, seg, src, copylen);
+}
+
+static inline void
+memset_stride(u16 seg, void *dst, u8 val, int setlen, int stride, int lines)
+{
+ for (; lines; lines--, dst+=stride)
+ memset_far(seg, dst, val, setlen);
+}
+
+static inline void
+memset16_stride(u16 seg, void *dst, u16 val, int setlen, int stride, int lines)
+{
+ for (; lines; lines--, dst+=stride)
+ memset16_far(seg, dst, val, setlen);
+}
+
+
+/****************************************************************
+ * Basic stdvga graphic manipulation
+ ****************************************************************/
+
+static void
+gfx_planar(struct gfx_op *op)
+{
+ if (!CONFIG_VGA_STDVGA_PORTS)
+ return;
+ void *dest_far = (void*)(op->y * op->linelength + op->x / 8);
+ int plane;
+ switch (op->op) {
+ default:
+ case GO_READ8:
+ memset(op->pixels, 0, sizeof(op->pixels));
+ for (plane = 0; plane < 4; plane++) {
+ stdvga_planar4_plane(plane);
+ u8 data = GET_FARVAR(SEG_GRAPH, *(u8*)dest_far);
+ int pixel;
+ for (pixel=0; pixel<8; pixel++)
+ op->pixels[pixel] |= ((data>>(7-pixel)) & 1) << plane;
+ }
+ break;
+ case GO_WRITE8:
+ for (plane = 0; plane<4; plane++) {
+ stdvga_planar4_plane(plane);
+ u8 data = 0;
+ int pixel;
+ for (pixel=0; pixel<8; pixel++)
+ data |= ((op->pixels[pixel]>>plane) & 1) << (7-pixel);
+ SET_FARVAR(SEG_GRAPH, *(u8*)dest_far, data);
+ }
+ break;
+ case GO_MEMSET:
+ for (plane = 0; plane < 4; plane++) {
+ stdvga_planar4_plane(plane);
+ u8 data = (op->pixels[0] & (1<<plane)) ? 0xff : 0x00;
+ memset_stride(SEG_GRAPH, dest_far, data
+ , op->xlen / 8, op->linelength, op->ylen);
+ }
+ break;
+ case GO_MEMMOVE: ;
+ void *src_far = (void*)(op->srcy * op->linelength + op->x / 8);
+ for (plane = 0; plane < 4; plane++) {
+ stdvga_planar4_plane(plane);
+ memmove_stride(SEG_GRAPH, dest_far, src_far
+ , op->xlen / 8, op->linelength, op->ylen);
+ }
+ break;
+ }
+ stdvga_planar4_plane(-1);
+}
+
+static void
+gfx_cga(struct gfx_op *op)
+{
+ int bpp = GET_GLOBAL(op->vmode_g->depth);
+ void *dest_far = (void*)(op->y / 2 * op->linelength + op->x / 8 * bpp);
+ switch (op->op) {
+ default:
+ case GO_READ8:
+ if (op->y & 1)
+ dest_far += 0x2000;
+ if (bpp == 1) {
+ u8 data = GET_FARVAR(SEG_CTEXT, *(u8*)dest_far);
+ int pixel;
+ for (pixel=0; pixel<8; pixel++)
+ op->pixels[pixel] = (data >> (7-pixel)) & 1;
+ } else {
+ u16 data = GET_FARVAR(SEG_CTEXT, *(u16*)dest_far);
+ data = be16_to_cpu(data);
+ int pixel;
+ for (pixel=0; pixel<8; pixel++)
+ op->pixels[pixel] = (data >> ((7-pixel)*2)) & 3;
+ }
+ break;
+ case GO_WRITE8:
+ if (op->y & 1)
+ dest_far += 0x2000;
+ if (bpp == 1) {
+ u8 data = 0;
+ int pixel;
+ for (pixel=0; pixel<8; pixel++)
+ data |= (op->pixels[pixel] & 1) << (7-pixel);
+ SET_FARVAR(SEG_CTEXT, *(u8*)dest_far, data);
+ } else {
+ u16 data = 0;
+ int pixel;
+ for (pixel=0; pixel<8; pixel++)
+ data |= (op->pixels[pixel] & 3) << ((7-pixel) * 2);
+ data = cpu_to_be16(data);
+ SET_FARVAR(SEG_CTEXT, *(u16*)dest_far, data);
+ }
+ break;
+ case GO_MEMSET: ;
+ u8 data = op->pixels[0];
+ if (bpp == 1)
+ data = (data&1) | ((data&1)<<1);
+ data &= 3;
+ data |= (data<<2) | (data<<4) | (data<<6);
+ memset_stride(SEG_CTEXT, dest_far, data
+ , op->xlen / 8 * bpp, op->linelength, op->ylen / 2);
+ memset_stride(SEG_CTEXT, dest_far + 0x2000, data
+ , op->xlen / 8 * bpp, op->linelength, op->ylen / 2);
+ break;
+ case GO_MEMMOVE: ;
+ void *src_far = (void*)(op->srcy / 2 * op->linelength + op->x / 8 * bpp);
+ memmove_stride(SEG_CTEXT, dest_far, src_far
+ , op->xlen / 8 * bpp, op->linelength, op->ylen / 2);
+ memmove_stride(SEG_CTEXT, dest_far + 0x2000, src_far + 0x2000
+ , op->xlen / 8 * bpp, op->linelength, op->ylen / 2);
+ break;
+ }
+}
+
+static void
+gfx_packed(struct gfx_op *op)
+{
+ void *dest_far = (void*)(op->y * op->linelength + op->x);
+ switch (op->op) {
+ default:
+ case GO_READ8:
+ memcpy_far(GET_SEG(SS), op->pixels, SEG_GRAPH, dest_far, 8);
+ break;
+ case GO_WRITE8:
+ memcpy_far(SEG_GRAPH, dest_far, GET_SEG(SS), op->pixels, 8);
+ break;
+ case GO_MEMSET:
+ memset_stride(SEG_GRAPH, dest_far, op->pixels[0]
+ , op->xlen, op->linelength, op->ylen);
+ break;
+ case GO_MEMMOVE: ;
+ void *src_far = (void*)(op->srcy * op->linelength + op->x);
+ memmove_stride(SEG_GRAPH, dest_far, src_far
+ , op->xlen, op->linelength, op->ylen);
+ break;
+ }
+}
+
+
+/****************************************************************
+ * Direct framebuffers in high mem
+ ****************************************************************/
+
+// Use int 1587 call to copy memory to/from the framebuffer.
+static void
+memcpy_high(void *dest, void *src, u32 len)
+{
+ u64 gdt[6];
+ gdt[2] = GDT_DATA | GDT_LIMIT(0xfffff) | GDT_BASE((u32)src);
+ gdt[3] = GDT_DATA | GDT_LIMIT(0xfffff) | GDT_BASE((u32)dest);
+
+ // Call int 1587 to copy data.
+ len/=2;
+ u32 flags;
+ u32 eax = 0x8700;
+ u32 si = (u32)&gdt;
+ SET_SEG(ES, GET_SEG(SS));
+ asm volatile(
+ "stc\n"
+ "int $0x15\n"
+ "cli\n"
+ "cld\n"
+ "pushfl\n"
+ "popl %0\n"
+ : "=r" (flags), "+a" (eax), "+S" (si), "+c" (len)
+ : : "cc", "memory");
+}
+
+static void
+memmove_stride_high(void *dst, void *src, int copylen, int stride, int lines)
+{
+ if (src < dst) {
+ dst += stride * (lines - 1);
+ src += stride * (lines - 1);
+ stride = -stride;
+ }
+ for (; lines; lines--, dst+=stride, src+=stride)
+ memcpy_high(dst, src, copylen);
+}
+
+// Map a CGA color to a "direct" mode rgb value.
+static u32
+get_color(int depth, u8 attr)
+{
+ int rbits, gbits, bbits;
+ switch (depth) {
+ case 15: rbits=5; gbits=5; bbits=5; break;
+ case 16: rbits=5; gbits=6; bbits=5; break;
+ default:
+ case 24: rbits=8; gbits=8; bbits=8; break;
+ }
+ int h = (attr&8) ? 1 : 0;
+ int r = (attr&4) ? 2 : 0, g = (attr&2) ? 2 : 0, b = (attr&1) ? 2 : 0;
+ if ((attr & 0xf) == 6)
+ g = 1;
+ int rv = DIV_ROUND_CLOSEST(((1<<rbits) - 1) * (r + h), 3);
+ int gv = DIV_ROUND_CLOSEST(((1<<gbits) - 1) * (g + h), 3);
+ int bv = DIV_ROUND_CLOSEST(((1<<bbits) - 1) * (b + h), 3);
+ return (rv << (gbits+bbits)) + (gv << bbits) + bv;
+}
+
+// Find the closest attribute for a given framebuffer color
+static u8
+reverse_color(int depth, u32 color)
+{
+ int rbits, gbits, bbits;
+ switch (depth) {
+ case 15: rbits=5; gbits=5; bbits=5; break;
+ case 16: rbits=5; gbits=6; bbits=5; break;
+ default:
+ case 24: rbits=8; gbits=8; bbits=8; break;
+ }
+ int rv = (color >> (gbits+bbits)) & ((1<<rbits)-1);
+ int gv = (color >> bbits) & ((1<<gbits)-1);
+ int bv = color & ((1<<bbits)-1);
+ int r = DIV_ROUND_CLOSEST(rv * 3, (1<<rbits) - 1);
+ int g = DIV_ROUND_CLOSEST(gv * 3, (1<<gbits) - 1);
+ int b = DIV_ROUND_CLOSEST(bv * 3, (1<<bbits) - 1);
+ int h = r && g && b && (r != 2 || g != 2 || b != 2);
+ return (h ? 8 : 0) | ((r-h) ? 4 : 0) | ((g-h) ? 2 : 0) | ((b-h) ? 1 : 0);
+}
+
+static void
+gfx_direct(struct gfx_op *op)
+{
+ void *fb = (void*)GET_GLOBAL(VBE_framebuffer);
+ if (!fb)
+ return;
+ int depth = GET_GLOBAL(op->vmode_g->depth);
+ int bypp = DIV_ROUND_UP(depth, 8);
+ void *dest_far = (fb + op->displaystart + op->y * op->linelength
+ + op->x * bypp);
+ switch (op->op) {
+ default:
+ case GO_READ8: {
+ u8 data[64];
+ memcpy_high(MAKE_FLATPTR(GET_SEG(SS), data), dest_far, bypp * 8);
+ int i;
+ for (i=0; i<8; i++)
+ op->pixels[i] = reverse_color(depth, *(u32*)&data[i*bypp]);
+ break;
+ }
+ case GO_WRITE8: {
+ u8 data[64];
+ int i;
+ for (i=0; i<8; i++)
+ *(u32*)&data[i*bypp] = get_color(depth, op->pixels[i]);
+ memcpy_high(dest_far, MAKE_FLATPTR(GET_SEG(SS), data), bypp * 8);
+ break;
+ }
+ case GO_MEMSET: {
+ u32 color = get_color(depth, op->pixels[0]);
+ u8 data[64];
+ int i;
+ for (i=0; i<8; i++)
+ *(u32*)&data[i*bypp] = color;
+ memcpy_high(dest_far, MAKE_FLATPTR(GET_SEG(SS), data), bypp * 8);
+ memcpy_high(dest_far + bypp * 8, dest_far, op->xlen * bypp - bypp * 8);
+ for (i=1; i < op->ylen; i++)
+ memcpy_high(dest_far + op->linelength * i
+ , dest_far, op->xlen * bypp);
+ break;
+ }
+ case GO_MEMMOVE: ;
+ void *src_far = (fb + op->displaystart + op->srcy * op->linelength
+ + op->x * bypp);
+ memmove_stride_high(dest_far, src_far
+ , op->xlen * bypp, op->linelength, op->ylen);
+ break;
+ }
+}
+
+
+/****************************************************************
+ * Gfx interface
+ ****************************************************************/
+
+// Prepare a struct gfx_op for use.
+void
+init_gfx_op(struct gfx_op *op, struct vgamode_s *vmode_g)
+{
+ memset(op, 0, sizeof(*op));
+ op->vmode_g = vmode_g;
+ op->linelength = vgahw_get_linelength(vmode_g);
+ op->displaystart = vgahw_get_displaystart(vmode_g);
+}
+
+// Issue a graphics operation.
+void
+handle_gfx_op(struct gfx_op *op)
+{
+ switch (GET_GLOBAL(op->vmode_g->memmodel)) {
+ case MM_PLANAR:
+ gfx_planar(op);
+ break;
+ case MM_CGA:
+ gfx_cga(op);
+ break;
+ case MM_PACKED:
+ gfx_packed(op);
+ break;
+ case MM_DIRECT:
+ gfx_direct(op);
+ break;
+ default:
+ break;
+ }
+}
+
+// Move characters when in graphics mode.
+static void
+gfx_move_chars(struct vgamode_s *vmode_g, struct cursorpos dest
+ , struct cursorpos src, struct cursorpos movesize)
+{
+ struct gfx_op op;
+ init_gfx_op(&op, vmode_g);
+ op.x = dest.x * 8;
+ op.xlen = movesize.x * 8;
+ int cheight = GET_BDA(char_height);
+ op.y = dest.y * cheight;
+ op.ylen = movesize.y * cheight;
+ op.srcy = src.y * cheight;
+ op.op = GO_MEMMOVE;
+ handle_gfx_op(&op);
+}
+
+// Clear area of screen in graphics mode.
+static void
+gfx_clear_chars(struct vgamode_s *vmode_g, struct cursorpos dest
+ , struct carattr ca, struct cursorpos clearsize)
+{
+ struct gfx_op op;
+ init_gfx_op(&op, vmode_g);
+ op.x = dest.x * 8;
+ op.xlen = clearsize.x * 8;
+ int cheight = GET_BDA(char_height);
+ op.y = dest.y * cheight;
+ op.ylen = clearsize.y * cheight;
+ op.pixels[0] = ca.attr;
+ if (vga_emulate_text())
+ op.pixels[0] = ca.attr >> 4;
+ op.op = GO_MEMSET;
+ handle_gfx_op(&op);
+}
+
+// Return the font for a given character
+struct segoff_s
+get_font_data(u8 c)
+{
+ int char_height = GET_BDA(char_height);
+ struct segoff_s font;
+ if (char_height == 8 && c >= 128) {
+ font = GET_IVT(0x1f);
+ c -= 128;
+ } else {
+ font = GET_IVT(0x43);
+ }
+ font.offset += c * char_height;
+ return font;
+}
+
+// Write a character to the screen in graphics mode.
+static void
+gfx_write_char(struct vgamode_s *vmode_g
+ , struct cursorpos cp, struct carattr ca)
+{
+ if (cp.x >= GET_BDA(video_cols))
+ return;
+
+ struct segoff_s font = get_font_data(ca.car);
+ struct gfx_op op;
+ init_gfx_op(&op, vmode_g);
+ op.x = cp.x * 8;
+ int cheight = GET_BDA(char_height);
+ op.y = cp.y * cheight;
+ u8 fgattr = ca.attr, bgattr = 0x00;
+ int usexor = 0;
+ if (vga_emulate_text()) {
+ if (ca.use_attr) {
+ bgattr = fgattr >> 4;
+ fgattr = fgattr & 0x0f;
+ } else {
+ // Read bottom right pixel of the cell to guess bg color
+ op.op = GO_READ8;
+ op.y += cheight-1;
+ handle_gfx_op(&op);
+ op.y -= cheight-1;
+ bgattr = op.pixels[7];
+ fgattr = bgattr ^ 0x7;
+ }
+ } else if (fgattr & 0x80 && GET_GLOBAL(vmode_g->depth) < 8) {
+ usexor = 1;
+ fgattr &= 0x7f;
+ }
+ int i;
+ for (i = 0; i < cheight; i++, op.y++) {
+ u8 fontline = GET_FARVAR(font.seg, *(u8*)(font.offset+i));
+ if (usexor) {
+ op.op = GO_READ8;
+ handle_gfx_op(&op);
+ int j;
+ for (j = 0; j < 8; j++)
+ op.pixels[j] ^= (fontline & (0x80>>j)) ? fgattr : 0x00;
+ } else {
+ int j;
+ for (j = 0; j < 8; j++)
+ op.pixels[j] = (fontline & (0x80>>j)) ? fgattr : bgattr;
+ }
+ op.op = GO_WRITE8;
+ handle_gfx_op(&op);
+ }
+}
+
+// Read a character from the screen in graphics mode.
+static struct carattr
+gfx_read_char(struct vgamode_s *vmode_g, struct cursorpos cp)
+{
+ u8 lines[16];
+ int cheight = GET_BDA(char_height);
+ if (cp.x >= GET_BDA(video_cols) || cheight > ARRAY_SIZE(lines))
+ goto fail;
+
+ // Read cell from screen
+ struct gfx_op op;
+ init_gfx_op(&op, vmode_g);
+ op.op = GO_READ8;
+ op.x = cp.x * 8;
+ op.y = cp.y * cheight;
+ int car = 0;
+ u8 fgattr = 0x00, bgattr = 0x00;
+ if (vga_emulate_text()) {
+ // Read bottom right pixel of the cell to guess bg color
+ op.y += cheight-1;
+ handle_gfx_op(&op);
+ op.y -= cheight-1;
+ bgattr = op.pixels[7];
+ fgattr = bgattr ^ 0x7;
+ // Report space character for blank cells (skip null character check)
+ car = 1;
+ }
+ u8 i, j;
+ for (i=0; i<cheight; i++, op.y++) {
+ u8 line = 0;
+ handle_gfx_op(&op);
+ for (j=0; j<8; j++)
+ if (op.pixels[j] != bgattr) {
+ line |= 0x80 >> j;
+ fgattr = op.pixels[j];
+ }
+ lines[i] = line;
+ }
+
+ // Determine font
+ for (; car<256; car++) {
+ struct segoff_s font = get_font_data(car);
+ if (memcmp_far(GET_SEG(SS), lines
+ , font.seg, (void*)(font.offset+0), cheight) == 0)
+ return (struct carattr){car, fgattr | (bgattr << 4), 0};
+ }
+fail:
+ return (struct carattr){0, 0, 0};
+}
+
+// Draw/undraw a cursor on the framebuffer by xor'ing the cursor cell
+void
+gfx_set_swcursor(struct vgamode_s *vmode_g, int enable, struct cursorpos cp)
+{
+ u16 cursor_type = get_cursor_shape();
+ u8 start = cursor_type >> 8, end = cursor_type & 0xff;
+ struct gfx_op op;
+ init_gfx_op(&op, vmode_g);
+ op.x = cp.x * 8;
+ int cheight = GET_BDA(char_height);
+ op.y = cp.y * cheight + start;
+
+ int i;
+ for (i = start; i < cheight && i <= end; i++, op.y++) {
+ op.op = GO_READ8;
+ handle_gfx_op(&op);
+ int j;
+ for (j = 0; j < 8; j++)
+ op.pixels[j] ^= 0x07;
+ op.op = GO_WRITE8;
+ handle_gfx_op(&op);
+ }
+}
+
+// Set the pixel at the given position.
+void
+vgafb_write_pixel(u8 color, u16 x, u16 y)
+{
+ struct vgamode_s *vmode_g = get_current_mode();
+ if (!vmode_g)
+ return;
+ vgafb_set_swcursor(0);
+
+ struct gfx_op op;
+ init_gfx_op(&op, vmode_g);
+ op.x = ALIGN_DOWN(x, 8);
+ op.y = y;
+ op.op = GO_READ8;
+ handle_gfx_op(&op);
+
+ int usexor = color & 0x80 && GET_GLOBAL(vmode_g->depth) < 8;
+ if (usexor)
+ op.pixels[x & 0x07] ^= color & 0x7f;
+ else
+ op.pixels[x & 0x07] = color;
+ op.op = GO_WRITE8;
+ handle_gfx_op(&op);
+}
+
+// Return the pixel at the given position.
+u8
+vgafb_read_pixel(u16 x, u16 y)
+{
+ struct vgamode_s *vmode_g = get_current_mode();
+ if (!vmode_g)
+ return 0;
+ vgafb_set_swcursor(0);
+
+ struct gfx_op op;
+ init_gfx_op(&op, vmode_g);
+ op.x = ALIGN_DOWN(x, 8);
+ op.y = y;
+ op.op = GO_READ8;
+ handle_gfx_op(&op);
+
+ return op.pixels[x & 0x07];
+}
+
+
+/****************************************************************
+ * Text ops
+ ****************************************************************/
+
+// Return the fb offset for the given character address when in text mode.
+void *
+text_address(struct cursorpos cp)
+{
+ int stride = GET_BDA(video_cols) * 2;
+ u32 pageoffset = GET_BDA(video_pagesize) * cp.page;
+ return (void*)pageoffset + cp.y * stride + cp.x * 2;
+}
+
+// Move characters on screen.
+void
+vgafb_move_chars(struct cursorpos dest
+ , struct cursorpos src, struct cursorpos movesize)
+{
+ struct vgamode_s *vmode_g = get_current_mode();
+ if (!vmode_g)
+ return;
+ vgafb_set_swcursor(0);
+
+ if (GET_GLOBAL(vmode_g->memmodel) != MM_TEXT) {
+ gfx_move_chars(vmode_g, dest, src, movesize);
+ return;
+ }
+
+ int stride = GET_BDA(video_cols) * 2;
+ memmove_stride(GET_GLOBAL(vmode_g->sstart)
+ , text_address(dest), text_address(src)
+ , movesize.x * 2, stride, movesize.y);
+}
+
+// Clear area of screen.
+void
+vgafb_clear_chars(struct cursorpos dest
+ , struct carattr ca, struct cursorpos clearsize)
+{
+ struct vgamode_s *vmode_g = get_current_mode();
+ if (!vmode_g)
+ return;
+ vgafb_set_swcursor(0);
+
+ if (GET_GLOBAL(vmode_g->memmodel) != MM_TEXT) {
+ gfx_clear_chars(vmode_g, dest, ca, clearsize);
+ return;
+ }
+
+ int stride = GET_BDA(video_cols) * 2;
+ u16 attr = ((ca.use_attr ? ca.attr : 0x07) << 8) | ca.car;
+ memset16_stride(GET_GLOBAL(vmode_g->sstart), text_address(dest), attr
+ , clearsize.x * 2, stride, clearsize.y);
+}
+
+// Write a character to the screen.
+void
+vgafb_write_char(struct cursorpos cp, struct carattr ca)
+{
+ struct vgamode_s *vmode_g = get_current_mode();
+ if (!vmode_g)
+ return;
+ vgafb_set_swcursor(0);
+
+ if (GET_GLOBAL(vmode_g->memmodel) != MM_TEXT) {
+ gfx_write_char(vmode_g, cp, ca);
+ return;
+ }
+
+ void *dest_far = text_address(cp);
+ if (ca.use_attr) {
+ u16 dummy = (ca.attr << 8) | ca.car;
+ SET_FARVAR(GET_GLOBAL(vmode_g->sstart), *(u16*)dest_far, dummy);
+ } else {
+ SET_FARVAR(GET_GLOBAL(vmode_g->sstart), *(u8*)dest_far, ca.car);
+ }
+}
+
+// Return the character at the given position on the screen.
+struct carattr
+vgafb_read_char(struct cursorpos cp)
+{
+ struct vgamode_s *vmode_g = get_current_mode();
+ if (!vmode_g)
+ return (struct carattr){0, 0, 0};
+ vgafb_set_swcursor(0);
+
+ if (GET_GLOBAL(vmode_g->memmodel) != MM_TEXT)
+ return gfx_read_char(vmode_g, cp);
+
+ u16 *dest_far = text_address(cp);
+ u16 v = GET_FARVAR(GET_GLOBAL(vmode_g->sstart), *dest_far);
+ return (struct carattr){v, v>>8, 0};
+}
+
+// Draw/undraw a cursor on the screen
+void
+vgafb_set_swcursor(int enable)
+{
+ if (!vga_emulate_text())
+ return;
+ u8 flags = GET_BDA_EXT(flags);
+ if (!!(flags & BF_SWCURSOR) == enable)
+ // Already in requested mode.
+ return;
+ struct vgamode_s *vmode_g = get_current_mode();
+ if (!vmode_g)
+ return;
+ struct cursorpos cp = get_cursor_pos(0xff);
+ if (cp.x >= GET_BDA(video_cols) || cp.y > GET_BDA(video_rows)
+ || GET_BDA(cursor_type) >= 0x2000)
+ // Cursor not visible
+ return;
+
+ SET_BDA_EXT(flags, (flags & ~BF_SWCURSOR) | (enable ? BF_SWCURSOR : 0));
+
+ if (GET_GLOBAL(vmode_g->memmodel) != MM_TEXT) {
+ gfx_set_swcursor(vmode_g, enable, cp);
+ return;
+ }
+
+ // In text mode, swap foreground and background attributes for cursor
+ void *dest_far = text_address(cp) + 1;
+ u8 attr = GET_FARVAR(GET_GLOBAL(vmode_g->sstart), *(u8*)dest_far);
+ attr = (attr >> 4) | (attr << 4);
+ SET_FARVAR(GET_GLOBAL(vmode_g->sstart), *(u8*)dest_far, attr);
+}
Code Review / kvmfornfv.git / blobdiff