vga.c

qemu虚拟机代码

                s->cr[0x18] = 0xff;
                s->cr[0x07] |= 0x10;
                s->cr[0x09] |= 0x40;
                
                if (s->vbe_regs[VBE_DISPI_INDEX_BPP] == 4) {
                    shift_control = 0;
                    s->sr[0x01] &= ~8; /* no double line */
                } else {
                    shift_control = 2;
                    s->sr[4] |= 0x08; /* set chain 4 mode */
                    s->sr[2] |= 0x0f; /* activate all planes */
                }
                s->gr[0x05] = (s->gr[0x05] & ~0x60) | (shift_control << 5);
                s->cr[0x09] &= ~0x9f; /* no double scan */
            } else {
                /* XXX: the bios should do that */
                s->bank_offset = 0;
            }
            s->vbe_regs[s->vbe_index] = val;
            break;
        case VBE_DISPI_INDEX_VIRT_WIDTH:
            {
                int w, h, line_offset;

                if (val < s->vbe_regs[VBE_DISPI_INDEX_XRES])
                    return;
                w = val;
                if (s->vbe_regs[VBE_DISPI_INDEX_BPP] == 4)
                    line_offset = w >> 1;
                else
                    line_offset = w * ((s->vbe_regs[VBE_DISPI_INDEX_BPP] + 7) >> 3);
                h = s->vram_size / line_offset;
                /* XXX: support weird bochs semantics ? */
                if (h < s->vbe_regs[VBE_DISPI_INDEX_YRES])
                    return;
                s->vbe_regs[VBE_DISPI_INDEX_VIRT_WIDTH] = w;
                s->vbe_regs[VBE_DISPI_INDEX_VIRT_HEIGHT] = h;
                s->vbe_line_offset = line_offset;
            }
            break;
        case VBE_DISPI_INDEX_X_OFFSET:
        case VBE_DISPI_INDEX_Y_OFFSET:
            {
                int x;
                s->vbe_regs[s->vbe_index] = val;
                s->vbe_start_addr = s->vbe_line_offset * s->vbe_regs[VBE_DISPI_INDEX_Y_OFFSET];
                x = s->vbe_regs[VBE_DISPI_INDEX_X_OFFSET];
                if (s->vbe_regs[VBE_DISPI_INDEX_BPP] == 4)
                    s->vbe_start_addr += x >> 1;
                else
                    s->vbe_start_addr += x * ((s->vbe_regs[VBE_DISPI_INDEX_BPP] + 7) >> 3);
                s->vbe_start_addr >>= 2;
            }
            break;
        default:
            break;
        }
    }
}
#endif

/* called for accesses between 0xa0000 and 0xc0000 */
uint32_t vga_mem_readb(void *opaque, target_phys_addr_t addr)
{
    VGAState *s = opaque;
    int memory_map_mode, plane;
    uint32_t ret;
    
    /* convert to VGA memory offset */
    memory_map_mode = (s->gr[6] >> 2) & 3;
    addr &= 0x1ffff;
    switch(memory_map_mode) {
    case 0:
        break;
    case 1:
        if (addr >= 0x10000)
            return 0xff;
        addr += s->bank_offset;
        break;
    case 2:
        addr -= 0x10000;
        if (addr >= 0x8000)
            return 0xff;
        break;
    default:
    case 3:
        addr -= 0x18000;
        if (addr >= 0x8000)
            return 0xff;
        break;
    }
    
    if (s->sr[4] & 0x08) {
        /* chain 4 mode : simplest access */
        ret = s->vram_ptr[addr];
    } else if (s->gr[5] & 0x10) {
        /* odd/even mode (aka text mode mapping) */
        plane = (s->gr[4] & 2) | (addr & 1);
        ret = s->vram_ptr[((addr & ~1) << 1) | plane];
    } else {
        /* standard VGA latched access */
        s->latch = ((uint32_t *)s->vram_ptr)[addr];

        if (!(s->gr[5] & 0x08)) {
            /* read mode 0 */
            plane = s->gr[4];
            ret = GET_PLANE(s->latch, plane);
        } else {
            /* read mode 1 */
            ret = (s->latch ^ mask16[s->gr[2]]) & mask16[s->gr[7]];
            ret |= ret >> 16;
            ret |= ret >> 8;
            ret = (~ret) & 0xff;
        }
    }
    return ret;
}

static uint32_t vga_mem_readw(void *opaque, target_phys_addr_t addr)
{
    uint32_t v;
#ifdef TARGET_WORDS_BIGENDIAN
    v = vga_mem_readb(opaque, addr) << 8;
    v |= vga_mem_readb(opaque, addr + 1);
#else
    v = vga_mem_readb(opaque, addr);
    v |= vga_mem_readb(opaque, addr + 1) << 8;
#endif
    return v;
}

static uint32_t vga_mem_readl(void *opaque, target_phys_addr_t addr)
{
    uint32_t v;
#ifdef TARGET_WORDS_BIGENDIAN
    v = vga_mem_readb(opaque, addr) << 24;
    v |= vga_mem_readb(opaque, addr + 1) << 16;
    v |= vga_mem_readb(opaque, addr + 2) << 8;
    v |= vga_mem_readb(opaque, addr + 3);
#else
    v = vga_mem_readb(opaque, addr);
    v |= vga_mem_readb(opaque, addr + 1) << 8;
    v |= vga_mem_readb(opaque, addr + 2) << 16;
    v |= vga_mem_readb(opaque, addr + 3) << 24;
#endif
    return v;
}

/* called for accesses between 0xa0000 and 0xc0000 */
void vga_mem_writeb(void *opaque, target_phys_addr_t addr, uint32_t val)
{
    VGAState *s = opaque;
    int memory_map_mode, plane, write_mode, b, func_select, mask;
    uint32_t write_mask, bit_mask, set_mask;

#ifdef DEBUG_VGA_MEM
    printf("vga: [0x%x] = 0x%02x\n", addr, val);
#endif
    /* convert to VGA memory offset */
    memory_map_mode = (s->gr[6] >> 2) & 3;
    addr &= 0x1ffff;
    switch(memory_map_mode) {
    case 0:
        break;
    case 1:
        if (addr >= 0x10000)
            return;
        addr += s->bank_offset;
        break;
    case 2:
        addr -= 0x10000;
        if (addr >= 0x8000)
            return;
        break;
    default:
    case 3:
        addr -= 0x18000;
        if (addr >= 0x8000)
            return;
        break;
    }
    
    if (s->sr[4] & 0x08) {
        /* chain 4 mode : simplest access */
        plane = addr & 3;
        mask = (1 << plane);
        if (s->sr[2] & mask) {
            s->vram_ptr[addr] = val;
#ifdef DEBUG_VGA_MEM
            printf("vga: chain4: [0x%x]\n", addr);
#endif
            s->plane_updated |= mask; /* only used to detect font change */
            cpu_physical_memory_set_dirty(s->vram_offset + addr);
        }
    } else if (s->gr[5] & 0x10) {
        /* odd/even mode (aka text mode mapping) */
        plane = (s->gr[4] & 2) | (addr & 1);
        mask = (1 << plane);
        if (s->sr[2] & mask) {
            addr = ((addr & ~1) << 1) | plane;
            s->vram_ptr[addr] = val;
#ifdef DEBUG_VGA_MEM
            printf("vga: odd/even: [0x%x]\n", addr);
#endif
            s->plane_updated |= mask; /* only used to detect font change */
            cpu_physical_memory_set_dirty(s->vram_offset + addr);
        }
    } else {
        /* standard VGA latched access */
        write_mode = s->gr[5] & 3;
        switch(write_mode) {
        default:
        case 0:
            /* rotate */
            b = s->gr[3] & 7;
            val = ((val >> b) | (val << (8 - b))) & 0xff;
            val |= val << 8;
            val |= val << 16;

            /* apply set/reset mask */
            set_mask = mask16[s->gr[1]];
            val = (val & ~set_mask) | (mask16[s->gr[0]] & set_mask);
            bit_mask = s->gr[8];
            break;
        case 1:
            val = s->latch;
            goto do_write;
        case 2:
            val = mask16[val & 0x0f];
            bit_mask = s->gr[8];
            break;
        case 3:
            /* rotate */
            b = s->gr[3] & 7;
            val = (val >> b) | (val << (8 - b));

            bit_mask = s->gr[8] & val;
            val = mask16[s->gr[0]];
            break;
        }

        /* apply logical operation */
        func_select = s->gr[3] >> 3;
        switch(func_select) {
        case 0:
        default:
            /* nothing to do */
            break;
        case 1:
            /* and */
            val &= s->latch;
            break;
        case 2:
            /* or */
            val |= s->latch;
            break;
        case 3:
            /* xor */
            val ^= s->latch;
            break;
        }

        /* apply bit mask */
        bit_mask |= bit_mask << 8;
        bit_mask |= bit_mask << 16;
        val = (val & bit_mask) | (s->latch & ~bit_mask);

    do_write:
        /* mask data according to sr[2] */
        mask = s->sr[2];
        s->plane_updated |= mask; /* only used to detect font change */
        write_mask = mask16[mask];
        ((uint32_t *)s->vram_ptr)[addr] = 
            (((uint32_t *)s->vram_ptr)[addr] & ~write_mask) | 
            (val & write_mask);
#ifdef DEBUG_VGA_MEM
            printf("vga: latch: [0x%x] mask=0x%08x val=0x%08x\n", 
                   addr * 4, write_mask, val);
#endif
            cpu_physical_memory_set_dirty(s->vram_offset + (addr << 2));
    }
}

static void vga_mem_writew(void *opaque, target_phys_addr_t addr, uint32_t val)
{
#ifdef TARGET_WORDS_BIGENDIAN
    vga_mem_writeb(opaque, addr, (val >> 8) & 0xff);
    vga_mem_writeb(opaque, addr + 1, val & 0xff);
#else
    vga_mem_writeb(opaque, addr, val & 0xff);
    vga_mem_writeb(opaque, addr + 1, (val >> 8) & 0xff);
#endif
}

static void vga_mem_writel(void *opaque, target_phys_addr_t addr, uint32_t val)
{
#ifdef TARGET_WORDS_BIGENDIAN
    vga_mem_writeb(opaque, addr, (val >> 24) & 0xff);
    vga_mem_writeb(opaque, addr + 1, (val >> 16) & 0xff);
    vga_mem_writeb(opaque, addr + 2, (val >> 8) & 0xff);
    vga_mem_writeb(opaque, addr + 3, val & 0xff);
#else
    vga_mem_writeb(opaque, addr, val & 0xff);
    vga_mem_writeb(opaque, addr + 1, (val >> 8) & 0xff);
    vga_mem_writeb(opaque, addr + 2, (val >> 16) & 0xff);
    vga_mem_writeb(opaque, addr + 3, (val >> 24) & 0xff);
#endif
}

typedef void vga_draw_glyph8_func(uint8_t *d, int linesize,
                             const uint8_t *font_ptr, int h,
                             uint32_t fgcol, uint32_t bgcol);
typedef void vga_draw_glyph9_func(uint8_t *d, int linesize,
                                  const uint8_t *font_ptr, int h, 
                                  uint32_t fgcol, uint32_t bgcol, int dup9);
typedef void vga_draw_line_func(VGAState *s1, uint8_t *d, 
                                const uint8_t *s, int width);

static inline unsigned int rgb_to_pixel8(unsigned int r, unsigned int g, unsigned b)
{
    return ((r >> 5) << 5) | ((g >> 5) << 2) | (b >> 6);
}

static inline unsigned int rgb_to_pixel15(unsigned int r, unsigned int g, unsigned b)
{
    return ((r >> 3) << 10) | ((g >> 3) << 5) | (b >> 3);
}

static inline unsigned int rgb_to_pixel16(unsigned int r, unsigned int g, unsigned b)
{
    return ((r >> 3) << 11) | ((g >> 2) << 5) | (b >> 3);
}

static inline unsigned int rgb_to_pixel32(unsigned int r, unsigned int g, unsigned b)
{
    return (r << 16) | (g << 8) | b;
}

#define DEPTH 8
#include "vga_template.h"

#define DEPTH 15
#include "vga_template.h"

#define DEPTH 16
#include "vga_template.h"

#define DEPTH 32
#include "vga_template.h"

static unsigned int rgb_to_pixel8_dup(unsigned int r, unsigned int g, unsigned b)
{
    unsigned int col;
    col = rgb_to_pixel8(r, g, b);
    col |= col << 8;
    col |= col << 16;
    return col;
}

static unsigned int rgb_to_pixel15_dup(unsigned int r, unsigned int g, unsigned b)
{
    unsigned int col;
    col = rgb_to_pixel15(r, g, b);
    col |= col << 16;
    return col;
}

static unsigned int rgb_to_pixel16_dup(unsigned int r, unsigned int g, unsigned b)
{
    unsigned int col;
    col = rgb_to_pixel16(r, g, b);
    col |= col << 16;
    return col;
}

static unsigned int rgb_to_pixel32_dup(unsigned int r, unsigned int g, unsigned b)
{
    unsigned int col;
    col = rgb_to_pixel32(r, g, b);
    return col;
}

/* return true if the palette was modified */
static int update_palette16(VGAState *s)
{
    int full_update, i;
    uint32_t v, col, *palette;

    full_update = 0;
    palette = s->last_palette;
    for(i = 0; i < 16; i++) {
        v = s->ar[i];
        if (s->ar[0x10] & 0x80)
            v = ((s->ar[0x14] & 0xf) << 4) | (v & 0xf);
        else
            v = ((s->ar[0x14] & 0xc) << 4) | (v & 0x3f);
        v = v * 3;
        col = s->rgb_to_pixel(c6_to_8(s->palette[v]), 
                              c6_to_8(s->palette[v + 1]), 
                              c6_to_8(s->palette[v + 2]));
        if (col != palette[i]) {
            full_update = 1;
            palette[i] = col;
        }
    }
    return full_update;
}

/* return true if the palette was modified */
static int update_palette256(VGAState *s)
{
    int full_update, i;
    uint32_t v, col, *palette;

    full_update = 0;
    palette = s->last_palette;
    v = 0;
    for(i = 0; i < 256; i++) {
        col = s->rgb_to_pixel(c6_to_8(s->palette[v]), 
                              c6_to_8(s->palette[v + 1]), 
                              c6_to_8(s->palette[v + 2]));
        if (col != palette[i]) {
            full_update = 1;
            palette[i] = col;
        }
        v += 3;
    }
    return full_update;
}

static void vga_get_offsets(VGAState *s, 
                            uint32_t *pline_offset, 
                            uint32_t *pstart_addr)
{
    uint32_t start_addr, line_offset;
#ifdef CONFIG_BOCHS_VBE
    if (s->vbe_regs[VBE_DISPI_INDEX_ENABLE] & VBE_DISPI_ENABLED) {
        line_offset = s->vbe_line_offset;
        start_addr = s->vbe_start_addr;
    } else
#endif
    {  
        /* compute line_offset in bytes */
        line_offset = s->cr[0x13];
        line_offset <<= 3;

        /* starting address */
        start_addr = s->cr[0x0d] | (s->cr[0x0c] << 8);
    }
    *pline_offset = line_offset;
    *pstart_addr = start_addr;
}

/* update start_addr and line_offset. Return TRUE if modified */
static int update_basic_params(VGAState *s)
{
    int full_update;
    uint32_t start_addr, line_offset, line_compare;
    
    full_update = 0;

    s->get_offsets(s, &line_offset, &start_addr);
    /* line compare */
    line_compare = s->cr[0x18] | 
        ((s->cr[0x07] & 0x10) << 4) |
        ((s->cr[0x09] & 0x40) << 3);

    if (line_offset != s->line_offset ||
        start_addr != s->start_addr ||
        line_compare != s->line_compare) {
        s->line_offset = line_offset;
        s->start_addr = start_addr;