/* * This file is part of the Palacios Virtual Machine Monitor developed * by the V3VEE Project with funding from the United States National * Science Foundation and the Department of Energy. * * The V3VEE Project is a joint project between Northwestern University * and the University of New Mexico. You can find out more at * http://www.v3vee.org * * Copyright (c) 2009, Robert Deloatch * Copyright (c) 2009, Steven Jaconette * Copyright (c) 2009, The V3VEE Project * All rights reserved. * * Author: Robdert Deloatch * Steven Jaconette * * This is free software. You are permitted to use, * redistribute, and modify it as specified in the file "V3VEE_LICENSE". */ #include #include #include #include #include #ifndef DEBUG_CGA #undef PrintDebug #define PrintDebug(fmt, args...) #endif #define START_ADDR 0xB8000 #define END_ADDR 0xC0000 #define FRAMEBUF_SIZE (END_ADDR - START_ADDR) #define SCREEN_SIZE 4000 #define BASE_CGA_PORT 0x3B0 #define NUM_COLS 80 #define NUM_ROWS 25 #define BYTES_PER_ROW (NUM_COLS * 2) #define BYTES_PER_COL 2 struct video_internal { uint8_t * framebuf; // These store the values for unhandled ports, in case of a read op uint8_t port_store[44]; uint8_t crtc_index_reg; // io port 3D4 uint8_t crtc_data_regs[25]; // io port 3D5 /* IMPORTANT: These are column offsets _NOT_ byte offsets */ uint16_t screen_offset; // relative to the framebuffer uint16_t cursor_offset; // relative to the framebuffer /* ** */ // updating the screen offset is not atomic, // so we need a temp variable to hold the partial update uint16_t tmp_screen_offset; uint8_t passthrough; struct v3_console_ops * ops; void * private_data; }; static void passthrough_in(uint16_t port, void * src, uint_t length) { switch (length) { case 1: *(uint8_t *)src = v3_inb(port); break; case 2: *(uint16_t *)src = v3_inw(port); break; case 4: *(uint32_t *)src = v3_indw(port); break; default: break; } } static void passthrough_out(uint16_t port, void * src, uint_t length) { switch (length) { case 1: v3_outb(port, *(uint8_t *)src); break; case 2: v3_outw(port, *(uint16_t *)src); break; case 4: v3_outdw(port, *(uint32_t *)src); break; default: break; } } static int video_write_mem(addr_t guest_addr, void * dest, uint_t length, void * priv_data) { struct vm_device * dev = (struct vm_device *)priv_data; struct video_internal * state = (struct video_internal *)dev->private_data; uint_t fb_offset = guest_addr - START_ADDR; uint_t screen_byte_offset = state->screen_offset * BYTES_PER_COL; uint_t screen_length; PrintDebug("Guest address: %p length = %d, fb_offset=%d, screen_offset=%d\n", (void *)guest_addr, length, fb_offset, screen_byte_offset); if (state->passthrough) { memcpy(state->framebuf + fb_offset, V3_VAddr((void *)guest_addr), length); } if ((fb_offset >= screen_byte_offset) && (fb_offset < (screen_byte_offset + SCREEN_SIZE))) { uint_t screen_pos = fb_offset - screen_byte_offset; uint_t x = (screen_pos % BYTES_PER_ROW) / BYTES_PER_COL; uint_t y = screen_pos / BYTES_PER_ROW; PrintDebug("Sending Screen update\n"); if (state->ops) { PrintDebug("\tcalling update_screen()\n"); /* avoid updates past end of screen */ screen_length = SCREEN_SIZE - screen_byte_offset; if (screen_length > length) screen_length = length; state->ops->update_screen(x, y, screen_length, state->private_data); } } return length; } static int video_read_port(uint16_t port, void * dest, uint_t length, struct vm_device * dev) { struct video_internal * video_state = (struct video_internal *)dev->private_data; PrintDebug("Video: Read port 0x%x\n", port); if (video_state->passthrough) { passthrough_in(port, dest, length); } return length; } static int video_write_port(uint16_t port, void * src, uint_t length, struct vm_device * dev) { struct video_internal * video_state = (struct video_internal *)dev->private_data; PrintDebug("Video: write port 0x%x...\n", port); if (video_state->passthrough) { passthrough_out(port, src, length); } return length; } static int crtc_data_write(uint16_t port, void * src, uint_t length, struct vm_device * dev) { struct video_internal * video_state = (struct video_internal *)dev->private_data; uint8_t val = *(uint8_t *)src; uint_t index = video_state->crtc_index_reg; if (length != 1) { PrintError("Invalid write length for port 0x%x\n", port); return -1; } PrintDebug("Video: write on port 0x%x... (val=0x%x)\n", port, val); video_state->crtc_data_regs[index] = val; switch (index) { case 0x0c: { // scroll high byte uint16_t tmp_val = val; video_state->tmp_screen_offset = ((tmp_val << 8) & 0xff00); break; } case 0x0d: { // Scroll low byte int diff = 0; video_state->tmp_screen_offset += val; diff = (video_state->tmp_screen_offset - video_state->screen_offset) / NUM_COLS; // Update the true offset value video_state->screen_offset = video_state->tmp_screen_offset; video_state->tmp_screen_offset = 0; PrintDebug("Scroll lines = %d, new screen offset=%d\n", diff, video_state->screen_offset * BYTES_PER_COL); if (video_state->ops) { if (video_state->ops->scroll(diff, video_state->private_data) == -1) { PrintError("Error sending scroll event\n"); return -1; } } break; } case 0x0E: { // Cursor adjustment High byte uint16_t tmp_val = val; video_state->cursor_offset = ((tmp_val << 8) & 0xff00); break; } case 0x0F: { // cursor adjustment low byte uint_t x = 0; uint_t y = 0; video_state->cursor_offset += val; x = video_state->cursor_offset % NUM_COLS; y = (video_state->cursor_offset - video_state->screen_offset) / NUM_COLS; PrintDebug("New Cursor Location; X=%d Y=%d\n", x, y); if (video_state->ops) { if (video_state->ops->update_cursor(x, y, video_state->private_data) == -1) { PrintError("Error updating cursor\n"); return -1; } } break; } default: break; } if (video_state->passthrough) { passthrough_out(port, src, length); } return length; } static int crtc_index_write(uint16_t port, void * src, uint_t length, struct vm_device * dev) { struct video_internal * video_state = (struct video_internal *)dev->private_data; if (length > 2) { PrintError("Invalid write length for crtc index register port: %d (0x%x)\n", port, port); return -1; } video_state->crtc_index_reg = *(uint8_t *)src; // Only do the passthrough IO for the first byte // the second byte will be done in the data register handler if (video_state->passthrough) { passthrough_out(port, src, 1); } if (length == 2) { if (crtc_data_write(port + 1, src + 1, length - 1, dev) != (length - 1)) { PrintError("could not handle implicit crtc data write\n"); return -1; } } return length; } int v3_cons_get_fb(struct vm_device * frontend_dev, uint8_t * dst, uint_t offset, uint_t length) { struct video_internal * state = (struct video_internal *)frontend_dev->private_data; uint_t screen_byte_offset = state->screen_offset * BYTES_PER_COL; PrintDebug("Getting framebuffer for screen; framebuf=%p, screen_offset=%d, offset=%d, length=%d\n", state->framebuf, screen_byte_offset, offset, length); memcpy(dst, state->framebuf + screen_byte_offset + offset, length); return 0; } static int free_device(struct vm_device * dev) { v3_unhook_mem(dev->vm, START_ADDR); return 0; } static struct v3_device_ops dev_ops = { .free = free_device, .reset = NULL, .start = NULL, .stop = NULL, }; static int cga_init(struct guest_info * vm, v3_cfg_tree_t * cfg) { struct video_internal * video_state = (struct video_internal *)V3_Malloc(sizeof(struct video_internal)); addr_t frame_buf_pa = 0; int enable_passthrough = 0; char * name = v3_cfg_val(cfg, "name"); enable_passthrough = (strcasecmp(v3_cfg_val(cfg, "passthrough"), "enable") == 0) ? 1 : 0; PrintDebug("video: init_device\n"); struct vm_device * dev = v3_allocate_device(name, &dev_ops, video_state); if (v3_attach_device(vm, dev) == -1) { PrintError("Could not attach device %s\n", name); return -1; } frame_buf_pa = (addr_t)V3_AllocPages(FRAMEBUF_SIZE / 4096); video_state->framebuf = V3_VAddr((void *)frame_buf_pa); memset(video_state->framebuf, 0, FRAMEBUF_SIZE); PrintDebug("PA of array: %p\n", (void *)frame_buf_pa); video_state->passthrough = enable_passthrough; video_state->ops = NULL; video_state->private_data = NULL; if (enable_passthrough) { PrintDebug("Enabling CGA Passthrough\n"); if (v3_hook_write_mem(vm, START_ADDR, END_ADDR, START_ADDR, &video_write_mem, dev) == -1) { PrintDebug("\n\nVideo Hook failed.\n\n"); } } else { if (v3_hook_write_mem(vm, START_ADDR, END_ADDR, frame_buf_pa, &video_write_mem, dev) == -1) { PrintDebug("\n\nVideo Hook failed.\n\n"); } } v3_dev_hook_io(dev, 0x3b0, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3b1, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3b2, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3b3, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3b4, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3b5, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3b6, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3b7, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3b8, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3b9, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3ba, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3bb, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3c0, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3c1, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3c2, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3c3, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3c4, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3c5, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3c6, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3c7, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3c8, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3c9, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3ca, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3cb, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3cc, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3cd, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3ce, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3cf, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3d0, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3d1, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3d2, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3d3, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3d4, &video_read_port, &crtc_index_write); v3_dev_hook_io(dev, 0x3d5, &video_read_port, &crtc_data_write); v3_dev_hook_io(dev, 0x3d6, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3d7, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3d8, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3d9, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3da, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3db, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3dc, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3dd, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3de, &video_read_port, &video_write_port); v3_dev_hook_io(dev, 0x3df, &video_read_port, &video_write_port); return 0; } device_register("CGA_VIDEO", cga_init); int v3_console_register_cga(struct vm_device * cga_dev, struct v3_console_ops * ops, void * private_data) { struct video_internal * video_state = (struct video_internal *)cga_dev->private_data; video_state->ops = ops; video_state->private_data = private_data; return 0; }