--- /dev/null
+/*
+ * Copyright (C) 2013 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+/** @file
+ *
+ * VESA frame buffer console
+ *
+ */
+
+#include <stdlib.h>
+#include <errno.h>
+#include <limits.h>
+#include <realmode.h>
+#include <ipxe/console.h>
+#include <ipxe/io.h>
+#include <ipxe/ansicol.h>
+#include <ipxe/fbcon.h>
+#include <ipxe/vesafb.h>
+#include <config/console.h>
+
+/* Avoid dragging in BIOS console if not otherwise used */
+extern struct console_driver bios_console;
+struct console_driver bios_console __attribute__ (( weak ));
+
+/* Disambiguate the various error causes */
+#define EIO_FAILED __einfo_error ( EINFO_EIO_FAILED )
+#define EINFO_EIO_FAILED \
+ __einfo_uniqify ( EINFO_EIO, 0x01, \
+ "Function call failed" )
+#define EIO_HARDWARE __einfo_error ( EINFO_EIO_HARDWARE )
+#define EINFO_EIO_HARDWARE \
+ __einfo_uniqify ( EINFO_EIO, 0x02, \
+ "Not supported in current configuration" )
+#define EIO_MODE __einfo_error ( EINFO_EIO_MODE )
+#define EINFO_EIO_MODE \
+ __einfo_uniqify ( EINFO_EIO, 0x03, \
+ "Invalid in current video mode" )
+#define EIO_VBE( code ) \
+ EUNIQ ( EINFO_EIO, (code), EIO_FAILED, EIO_HARDWARE, EIO_MODE )
+
+/* Set default console usage if applicable */
+#if ! ( defined ( CONSOLE_VESAFB ) && CONSOLE_EXPLICIT ( CONSOLE_VESAFB ) )
+#undef CONSOLE_VESAFB
+#define CONSOLE_VESAFB ( CONSOLE_USAGE_ALL & ~CONSOLE_USAGE_LOG )
+#endif
+
+/** Font corresponding to selected character width and height */
+#define VESAFB_FONT VBE_FONT_8x16
+
+/* Forward declaration */
+struct console_driver vesafb_console __console_driver;
+
+/** A VESA frame buffer */
+struct vesafb {
+ /** Frame buffer console */
+ struct fbcon fbcon;
+ /** Physical start address */
+ physaddr_t start;
+ /** Pixel geometry */
+ struct fbcon_geometry pixel;
+ /** Margin */
+ struct fbcon_margin margin;
+ /** Colour mapping */
+ struct fbcon_colour_map map;
+ /** Font definition */
+ struct fbcon_font font;
+ /** Saved VGA mode */
+ uint8_t saved_mode;
+};
+
+/** The VESA frame buffer */
+static struct vesafb vesafb;
+
+/** Base memory buffer used for VBE calls */
+union vbe_buffer {
+ /** VBE controller information block */
+ struct vbe_controller_info controller;
+ /** VBE mode information block */
+ struct vbe_mode_info mode;
+};
+static union vbe_buffer __bss16 ( vbe_buf );
+#define vbe_buf __use_data16 ( vbe_buf )
+
+/**
+ * Convert VBE status code to iPXE status code
+ *
+ * @v status VBE status code
+ * @ret rc Return status code
+ */
+static int vesafb_rc ( unsigned int status ) {
+ unsigned int code;
+
+ if ( ( status & 0xff ) != 0x4f )
+ return -ENOTSUP;
+ code = ( ( status >> 8 ) & 0xff );
+ return ( code ? -EIO_VBE ( code ) : 0 );
+}
+
+/**
+ * Get font definition
+ *
+ */
+static void vesafb_font ( void ) {
+ struct segoff font;
+
+ /* Get font information
+ *
+ * Working around gcc bugs is icky here. The value we want is
+ * returned in %ebp, but there's no way to specify %ebp in an
+ * output constraint. We can't put %ebp in the clobber list,
+ * because this tends to cause random build failures on some
+ * gcc versions. We can't manually push/pop %ebp and return
+ * the value via a generic register output constraint, because
+ * gcc might choose to use %ebp to satisfy that constraint
+ * (and we have no way to prevent it from so doing).
+ *
+ * Work around this hideous mess by using %ecx and %edx as the
+ * output registers, since they get clobbered anyway.
+ */
+ __asm__ __volatile__ ( REAL_CODE ( "pushw %%bp\n\t" /* gcc bug */
+ "int $0x10\n\t"
+ "movw %%es, %%cx\n\t"
+ "movw %%bp, %%dx\n\t"
+ "popw %%bp\n\t" /* gcc bug */ )
+ : "=c" ( font.segment ),
+ "=d" ( font.offset )
+ : "a" ( VBE_GET_FONT ),
+ "b" ( VESAFB_FONT ) );
+ DBGC ( &vbe_buf, "VESAFB has font %04x at %04x:%04x\n",
+ VESAFB_FONT, font.segment, font.offset );
+ vesafb.font.start = real_to_user ( font.segment, font.offset );
+}
+
+/**
+ * Get VBE mode list
+ *
+ * @ret mode_numbers Mode number list (terminated with VBE_MODE_END)
+ * @ret rc Return status code
+ *
+ * The caller is responsible for eventually freeing the mode list.
+ */
+static int vesafb_mode_list ( uint16_t **mode_numbers ) {
+ struct vbe_controller_info *controller = &vbe_buf.controller;
+ userptr_t video_mode_ptr;
+ uint16_t mode_number;
+ uint16_t status;
+ size_t len;
+ int rc;
+
+ /* Avoid returning uninitialised data on error */
+ *mode_numbers = NULL;
+
+ /* Get controller information block */
+ controller->vbe_signature = 0;
+ __asm__ __volatile__ ( REAL_CODE ( "int $0x10" )
+ : "=a" ( status )
+ : "a" ( VBE_CONTROLLER_INFO ),
+ "D" ( __from_data16 ( controller ) )
+ : "memory", "ebx", "edx" );
+ if ( ( rc = vesafb_rc ( status ) ) != 0 ) {
+ DBGC ( &vbe_buf, "VESAFB could not get controller information: "
+ "[%04x] %s\n", status, strerror ( rc ) );
+ return rc;
+ }
+ if ( controller->vbe_signature != VBE_CONTROLLER_SIGNATURE ) {
+ DBGC ( &vbe_buf, "VESAFB invalid controller signature "
+ "\"%c%c%c%c\"\n", ( controller->vbe_signature >> 0 ),
+ ( controller->vbe_signature >> 8 ),
+ ( controller->vbe_signature >> 16 ),
+ ( controller->vbe_signature >> 24 ) );
+ DBGC_HDA ( &vbe_buf, 0, controller, sizeof ( *controller ) );
+ return -EINVAL;
+ }
+ DBGC ( &vbe_buf, "VESAFB found VBE version %d.%d with mode list at "
+ "%04x:%04x\n", controller->vbe_major_version,
+ controller->vbe_minor_version,
+ controller->video_mode_ptr.segment,
+ controller->video_mode_ptr.offset );
+
+ /* Calculate length of mode list */
+ video_mode_ptr = real_to_user ( controller->video_mode_ptr.segment,
+ controller->video_mode_ptr.offset );
+ len = 0;
+ do {
+ copy_from_user ( &mode_number, video_mode_ptr, len,
+ sizeof ( mode_number ) );
+ len += sizeof ( mode_number );
+ } while ( mode_number != VBE_MODE_END );
+
+ /* Allocate and fill mode list */
+ *mode_numbers = malloc ( len );
+ if ( ! *mode_numbers )
+ return -ENOMEM;
+ copy_from_user ( *mode_numbers, video_mode_ptr, 0, len );
+
+ return 0;
+}
+
+/**
+ * Get video mode information
+ *
+ * @v mode_number Mode number
+ * @ret rc Return status code
+ */
+static int vesafb_mode_info ( unsigned int mode_number ) {
+ struct vbe_mode_info *mode = &vbe_buf.mode;
+ uint16_t status;
+ int rc;
+
+ /* Get mode information */
+ __asm__ __volatile__ ( REAL_CODE ( "int $0x10" )
+ : "=a" ( status )
+ : "a" ( VBE_MODE_INFO ),
+ "c" ( mode_number ),
+ "D" ( __from_data16 ( mode ) )
+ : "memory" );
+ if ( ( rc = vesafb_rc ( status ) ) != 0 ) {
+ DBGC ( &vbe_buf, "VESAFB could not get mode %04x information: "
+ "[%04x] %s\n", mode_number, status, strerror ( rc ) );
+ return rc;
+ }
+ DBGC ( &vbe_buf, "VESAFB mode %04x %dx%d %dbpp(%d:%d:%d:%d) model "
+ "%02x [x%d]%s%s%s%s%s\n", mode_number, mode->x_resolution,
+ mode->y_resolution, mode->bits_per_pixel, mode->rsvd_mask_size,
+ mode->red_mask_size, mode->green_mask_size, mode->blue_mask_size,
+ mode->memory_model, ( mode->number_of_image_pages + 1 ),
+ ( ( mode->mode_attributes & VBE_MODE_ATTR_SUPPORTED ) ?
+ "" : " [unsupported]" ),
+ ( ( mode->mode_attributes & VBE_MODE_ATTR_TTY ) ?
+ " [tty]" : "" ),
+ ( ( mode->mode_attributes & VBE_MODE_ATTR_GRAPHICS ) ?
+ "" : " [text]" ),
+ ( ( mode->mode_attributes & VBE_MODE_ATTR_LINEAR ) ?
+ "" : " [nonlinear]" ),
+ ( ( mode->mode_attributes & VBE_MODE_ATTR_TRIPLE_BUF ) ?
+ " [buf]" : "" ) );
+
+ return 0;
+}
+
+/**
+ * Set video mode
+ *
+ * @v mode_number Mode number
+ * @ret rc Return status code
+ */
+static int vesafb_set_mode ( unsigned int mode_number ) {
+ struct vbe_mode_info *mode = &vbe_buf.mode;
+ uint16_t status;
+ int rc;
+
+ /* Get mode information */
+ if ( ( rc = vesafb_mode_info ( mode_number ) ) != 0 )
+ return rc;
+
+ /* Record mode parameters */
+ vesafb.start = mode->phys_base_ptr;
+ vesafb.pixel.width = mode->x_resolution;
+ vesafb.pixel.height = mode->y_resolution;
+ vesafb.pixel.len = ( ( mode->bits_per_pixel + 7 ) / 8 );
+ vesafb.pixel.stride = mode->bytes_per_scan_line;
+ DBGC ( &vbe_buf, "VESAFB mode %04x has frame buffer at %08x\n",
+ mode_number, mode->phys_base_ptr );
+
+ /* Initialise font colours */
+ vesafb.map.red_scale = ( 8 - mode->red_mask_size );
+ vesafb.map.green_scale = ( 8 - mode->green_mask_size );
+ vesafb.map.blue_scale = ( 8 - mode->blue_mask_size );
+ vesafb.map.red_lsb = mode->red_field_position;
+ vesafb.map.green_lsb = mode->green_field_position;
+ vesafb.map.blue_lsb = mode->blue_field_position;
+
+ /* Select this mode */
+ __asm__ __volatile__ ( REAL_CODE ( "int $0x10" )
+ : "=a" ( status )
+ : "a" ( VBE_SET_MODE ),
+ "b" ( mode_number ) );
+ if ( ( rc = vesafb_rc ( status ) ) != 0 ) {
+ DBGC ( &vbe_buf, "VESAFB could not set mode %04x: [%04x] %s\n",
+ mode_number, status, strerror ( rc ) );
+ return rc;
+ }
+
+ return 0;
+}
+
+/**
+ * Select video mode
+ *
+ * @v mode_numbers Mode number list (terminated with VBE_MODE_END)
+ * @v min_width Minimum required width (in pixels)
+ * @v min_height Minimum required height (in pixels)
+ * @v min_bpp Minimum required colour depth (in bits per pixel)
+ * @ret mode_number Mode number, or negative error
+ */
+static int vesafb_select_mode ( const uint16_t *mode_numbers,
+ unsigned int min_width, unsigned int min_height,
+ unsigned int min_bpp ) {
+ struct vbe_mode_info *mode = &vbe_buf.mode;
+ int best_mode_number = -ENOENT;
+ unsigned int best_score = INT_MAX;
+ unsigned int score;
+ uint16_t mode_number;
+ int rc;
+
+ /* Find the first suitable mode */
+ while ( ( mode_number = *(mode_numbers++) ) != VBE_MODE_END ) {
+
+ /* Force linear mode variant */
+ mode_number |= VBE_MODE_LINEAR;
+
+ /* Get mode information */
+ if ( ( rc = vesafb_mode_info ( mode_number ) ) != 0 )
+ continue;
+
+ /* Skip unusable modes */
+ if ( ( mode->mode_attributes & ( VBE_MODE_ATTR_SUPPORTED |
+ VBE_MODE_ATTR_GRAPHICS |
+ VBE_MODE_ATTR_LINEAR ) ) !=
+ ( VBE_MODE_ATTR_SUPPORTED | VBE_MODE_ATTR_GRAPHICS |
+ VBE_MODE_ATTR_LINEAR ) ) {
+ continue;
+ }
+ if ( mode->memory_model != VBE_MODE_MODEL_DIRECT_COLOUR )
+ continue;
+
+ /* Skip modes not meeting the requirements */
+ if ( ( mode->x_resolution < min_width ) ||
+ ( mode->y_resolution < min_height ) ||
+ ( mode->bits_per_pixel < min_bpp ) ) {
+ continue;
+ }
+
+ /* Select this mode if it has the best (i.e. lowest)
+ * score. We choose the scoring system to favour
+ * modes close to the specified width and height;
+ * within modes of the same width and height we prefer
+ * a higher colour depth.
+ */
+ score = ( ( mode->x_resolution * mode->y_resolution ) -
+ mode->bits_per_pixel );
+ if ( score < best_score ) {
+ best_mode_number = mode_number;
+ best_score = score;
+ }
+ }
+
+ if ( best_mode_number >= 0 ) {
+ DBGC ( &vbe_buf, "VESAFB selected mode %04x\n",
+ best_mode_number );
+ } else {
+ DBGC ( &vbe_buf, "VESAFB found no suitable mode\n" );
+ }
+
+ return best_mode_number;
+}
+
+/**
+ * Restore video mode
+ *
+ */
+static void vesafb_restore ( void ) {
+ uint32_t discard_a;
+
+ /* Restore saved VGA mode */
+ __asm__ __volatile__ ( REAL_CODE ( "int $0x10" )
+ : "=a" ( discard_a )
+ : "a" ( VBE_SET_VGA_MODE | vesafb.saved_mode ) );
+ DBGC ( &vbe_buf, "VESAFB restored VGA mode %#02x\n",
+ vesafb.saved_mode );
+}
+
+/**
+ * Initialise VESA frame buffer
+ *
+ * @v config Console configuration, or NULL to reset
+ * @ret rc Return status code
+ */
+static int vesafb_init ( struct console_configuration *config ) {
+ uint32_t discard_b;
+ uint16_t *mode_numbers;
+ unsigned int xgap;
+ unsigned int ygap;
+ unsigned int left;
+ unsigned int right;
+ unsigned int top;
+ unsigned int bottom;
+ int mode_number;
+ int rc;
+
+ /* Record current VGA mode */
+ __asm__ __volatile__ ( REAL_CODE ( "int $0x10" )
+ : "=a" ( vesafb.saved_mode ), "=b" ( discard_b )
+ : "a" ( VBE_GET_VGA_MODE ) );
+ DBGC ( &vbe_buf, "VESAFB saved VGA mode %#02x\n", vesafb.saved_mode );
+
+ /* Get VESA mode list */
+ if ( ( rc = vesafb_mode_list ( &mode_numbers ) ) != 0 )
+ goto err_mode_list;
+
+ /* Select mode */
+ if ( ( mode_number = vesafb_select_mode ( mode_numbers, config->width,
+ config->height,
+ config->depth ) ) < 0 ) {
+ rc = mode_number;
+ goto err_select_mode;
+ }
+
+ /* Set mode */
+ if ( ( rc = vesafb_set_mode ( mode_number ) ) != 0 )
+ goto err_set_mode;
+
+ /* Calculate margin. If the actual screen size is larger than
+ * the requested screen size, then update the margins so that
+ * the margin remains relative to the requested screen size.
+ * (As an exception, if a zero margin was specified then treat
+ * this as meaning "expand to edge of actual screen".)
+ */
+ xgap = ( vesafb.pixel.width - config->width );
+ ygap = ( vesafb.pixel.height - config->height );
+ left = ( xgap / 2 );
+ right = ( xgap - left );
+ top = ( ygap / 2 );
+ bottom = ( ygap - top );
+ vesafb.margin.left = ( config->left + ( config->left ? left : 0 ) );
+ vesafb.margin.right = ( config->right + ( config->right ? right : 0 ) );
+ vesafb.margin.top = ( config->top + ( config->top ? top : 0 ) );
+ vesafb.margin.bottom =
+ ( config->bottom + ( config->bottom ? bottom : 0 ) );
+
+ /* Get font data */
+ vesafb_font();
+
+ /* Initialise frame buffer console */
+ if ( ( rc = fbcon_init ( &vesafb.fbcon, phys_to_user ( vesafb.start ),
+ &vesafb.pixel, &vesafb.margin, &vesafb.map,
+ &vesafb.font, config->pixbuf ) ) != 0 )
+ goto err_fbcon_init;
+
+ free ( mode_numbers );
+ return 0;
+
+ fbcon_fini ( &vesafb.fbcon );
+ err_fbcon_init:
+ err_set_mode:
+ vesafb_restore();
+ err_select_mode:
+ free ( mode_numbers );
+ err_mode_list:
+ return rc;
+}
+
+/**
+ * Finalise VESA frame buffer
+ *
+ */
+static void vesafb_fini ( void ) {
+
+ /* Finalise frame buffer console */
+ fbcon_fini ( &vesafb.fbcon );
+
+ /* Restore saved VGA mode */
+ vesafb_restore();
+}
+
+/**
+ * Print a character to current cursor position
+ *
+ * @v character Character
+ */
+static void vesafb_putchar ( int character ) {
+
+ fbcon_putchar ( &vesafb.fbcon, character );
+}
+
+/**
+ * Configure console
+ *
+ * @v config Console configuration, or NULL to reset
+ * @ret rc Return status code
+ */
+static int vesafb_configure ( struct console_configuration *config ) {
+ int rc;
+
+ /* Reset console, if applicable */
+ if ( ! vesafb_console.disabled ) {
+ vesafb_fini();
+ bios_console.disabled &= ~CONSOLE_DISABLED_OUTPUT;
+ ansicol_reset_magic();
+ }
+ vesafb_console.disabled = CONSOLE_DISABLED;
+
+ /* Do nothing more unless we have a usable configuration */
+ if ( ( config == NULL ) ||
+ ( config->width == 0 ) || ( config->height == 0 ) ) {
+ return 0;
+ }
+
+ /* Initialise VESA frame buffer */
+ if ( ( rc = vesafb_init ( config ) ) != 0 )
+ return rc;
+
+ /* Mark console as enabled */
+ vesafb_console.disabled = 0;
+ bios_console.disabled |= CONSOLE_DISABLED_OUTPUT;
+
+ /* Set magic colour to transparent if we have a background picture */
+ if ( config->pixbuf )
+ ansicol_set_magic_transparent();
+
+ return 0;
+}
+
+/** VESA frame buffer console driver */
+struct console_driver vesafb_console __console_driver = {
+ .usage = CONSOLE_VESAFB,
+ .putchar = vesafb_putchar,
+ .configure = vesafb_configure,
+ .disabled = CONSOLE_DISABLED,
+};
Code Review / kvmfornfv.git / blobdiff