--- /dev/null
+/*
+ * Copyright (C) 2015 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 (at your option) 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.
+ *
+ * You can also choose to distribute this program under the terms of
+ * the Unmodified Binary Distribution Licence (as given in the file
+ * COPYING.UBDL), provided that you have satisfied its requirements.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
+
+#include <stdint.h>
+#include <string.h>
+#include <errno.h>
+#include <ipxe/console.h>
+#include <ipxe/init.h>
+#include <realmode.h>
+#include <int13.h>
+#include <config/console.h>
+
+/** @file
+ *
+ * INT13 disk log console
+ *
+ */
+
+/* Set default console usage if applicable */
+#if ! ( defined ( CONSOLE_INT13 ) && CONSOLE_EXPLICIT ( CONSOLE_INT13 ) )
+#undef CONSOLE_INT13
+#define CONSOLE_INT13 ( CONSOLE_USAGE_ALL & ~CONSOLE_USAGE_LOG )
+#endif
+
+/** Disk drive number */
+#define INT13CON_DRIVE 0x80
+
+/** Log partition type */
+#define INT13CON_PARTITION_TYPE 0xe0
+
+/** Maximum number of outstanding unwritten characters */
+#define INT13CON_MAX_UNWRITTEN 64
+
+/** Log partition header */
+struct int13con_header {
+ /** Magic signature */
+ char magic[10];
+} __attribute__ (( packed ));
+
+/** Log partition magic signature */
+#define INT13CON_MAGIC "iPXE LOG\n\n"
+
+/** Sector buffer */
+static uint8_t __bss16_array ( int13con_buffer, [INT13_BLKSIZE] );
+#define int13con_buffer __use_data16 ( int13con_buffer )
+
+/** Disk address packet */
+static struct int13_disk_address __bss16 ( int13con_address );
+#define int13con_address __use_data16 ( int13con_address )
+
+/** Current LBA */
+static uint64_t int13con_lba;
+
+/** Maximum LBA */
+static uint64_t int13con_max_lba;
+
+/** Current offset within sector */
+static size_t int13con_offset;
+
+/** Number of unwritten characters */
+static size_t int13con_unwritten;
+
+struct console_driver int13con __console_driver;
+
+/**
+ * Read/write disk sector
+ *
+ * @v op Operation
+ * @v lba Logical block address
+ * @ret rc Return status code
+ */
+static int int13con_rw ( unsigned int op, uint64_t lba ) {
+ uint8_t error;
+
+ /* Construct disk address packet */
+ int13con_address.bufsize = sizeof ( int13con_address );
+ int13con_address.count = 1;
+ int13con_address.buffer.segment = rm_ds;
+ int13con_address.buffer.offset = __from_data16 ( int13con_buffer );
+ int13con_address.lba = lba;
+
+ /* Issue INT13 */
+ __asm__ ( REAL_CODE ( "int $0x13\n\t" )
+ : "=a" ( error )
+ : "0" ( op << 8 ), "d" ( INT13CON_DRIVE ),
+ "S" ( __from_data16 ( &int13con_address ) ) );
+ if ( error ) {
+ DBG ( "INT13CON operation %04x failed: %02x\n",
+ op, error );
+ return -EIO;
+ }
+
+ return 0;
+}
+
+/**
+ * Write character to console
+ *
+ * @v character Character
+ */
+static void int13con_putchar ( int character ) {
+ static int busy;
+ int rc;
+
+ /* Ignore if we are already mid-logging */
+ if ( busy )
+ return;
+ busy = 1;
+
+ /* Write character to buffer */
+ int13con_buffer[int13con_offset++] = character;
+ int13con_unwritten++;
+
+ /* Write sector to disk, if applicable */
+ if ( ( int13con_offset == INT13_BLKSIZE ) ||
+ ( int13con_unwritten == INT13CON_MAX_UNWRITTEN ) ||
+ ( character == '\n' ) ) {
+
+ /* Write sector to disk */
+ if ( ( rc = int13con_rw ( INT13_EXTENDED_WRITE,
+ int13con_lba ) ) != 0 ) {
+ DBG ( "INT13CON could not write log\n" );
+ /* Ignore and continue; there's nothing we can do */
+ }
+
+ /* Reset count of unwritten characters */
+ int13con_unwritten = 0;
+ }
+
+ /* Move to next sector, if applicable */
+ if ( int13con_offset == INT13_BLKSIZE ) {
+
+ /* Disable console if we have run out of space */
+ if ( int13con_lba >= int13con_max_lba )
+ int13con.disabled = 1;
+
+ /* Clear log buffer */
+ memset ( int13con_buffer, 0, sizeof ( int13con_buffer ) );
+ int13con_offset = 0;
+
+ /* Move to next sector */
+ int13con_lba++;
+ }
+
+ /* Clear busy flag */
+ busy = 0;
+}
+
+/**
+ * Find log partition
+ *
+ * @ret rc Return status code
+ */
+static int int13con_find ( void ) {
+ struct master_boot_record *mbr =
+ ( ( struct master_boot_record * ) int13con_buffer );
+ struct int13con_header *hdr =
+ ( ( struct int13con_header * ) int13con_buffer );
+ struct partition_table_entry part[4];
+ unsigned int i;
+ int rc;
+
+ /* Read MBR */
+ if ( ( rc = int13con_rw ( INT13_EXTENDED_READ, 0 ) ) != 0 ) {
+ DBG ( "INT13CON could not read MBR: %s\n", strerror ( rc ) );
+ return rc;
+ }
+
+ /* Check MBR magic */
+ if ( mbr->magic != INT13_MBR_MAGIC ) {
+ DBG ( "INT13CON incorrect MBR magic\n" );
+ DBG2_HDA ( 0, mbr, sizeof ( *mbr ) );
+ return -EINVAL;
+ }
+
+ /* Look for magic partition */
+ memcpy ( part, mbr->partitions, sizeof ( part ) );
+ for ( i = 0 ; i < ( sizeof ( part ) / sizeof ( part[0] ) ) ; i++ ) {
+
+ /* Skip partitions of the wrong type */
+ if ( part[i].type != INT13CON_PARTITION_TYPE )
+ continue;
+
+ /* Read partition header */
+ if ( ( rc = int13con_rw ( INT13_EXTENDED_READ,
+ part[i].start ) ) != 0 ) {
+ DBG ( "INT13CON partition %d could not read header: "
+ "%s\n", ( i + 1 ), strerror ( rc ) );
+ continue;
+ }
+
+ /* Check partition header */
+ if ( memcmp ( hdr->magic, INT13CON_MAGIC,
+ sizeof ( hdr->magic ) ) != 0 ) {
+ DBG ( "INT13CON partition %d bad magic\n", ( i + 1 ) );
+ DBG2_HDA ( 0, hdr, sizeof ( *hdr ) );
+ continue;
+ }
+
+ /* Found log partition */
+ DBG ( "INT13CON partition %d at [%08x,%08x)\n", ( i + 1 ),
+ part[i].start, ( part[i].start + part[i].length ) );
+ int13con_lba = part[i].start;
+ int13con_max_lba = ( part[i].start + part[i].length - 1 );
+
+ /* Initialise log buffer */
+ memset ( &int13con_buffer[ sizeof ( *hdr ) ], 0,
+ ( sizeof ( int13con_buffer ) - sizeof ( *hdr ) ) );
+ int13con_offset = sizeof ( hdr->magic );
+
+ return 0;
+ }
+
+ DBG ( "INT13CON found no log partition\n" );
+ return -ENOENT;
+}
+
+/**
+ * Initialise INT13 console
+ *
+ */
+static void int13con_init ( void ) {
+ uint8_t error;
+ uint16_t check;
+ unsigned int discard_c;
+ unsigned int discard_d;
+ int rc;
+
+ /* Check for INT13 extensions */
+ __asm__ __volatile__ ( REAL_CODE ( "int $0x13\n\t"
+ "setc %%al\n\t" )
+ : "=a" ( error ), "=b" ( check ),
+ "=c" ( discard_c ), "=d" ( discard_d )
+ : "0" ( INT13_EXTENSION_CHECK << 8 ),
+ "1" ( 0x55aa ), "3" ( INT13CON_DRIVE ) );
+ if ( error || ( check != 0xaa55 ) ) {
+ DBG ( "INT13CON missing extensions (%02x,%04x)\n",
+ error, check );
+ return;
+ }
+
+ /* Locate log partition */
+ if ( ( rc = int13con_find() ) != 0)
+ return;
+
+ /* Enable console */
+ int13con.disabled = 0;
+}
+
+/**
+ * INT13 console initialisation function
+ */
+struct init_fn int13con_init_fn __init_fn ( INIT_CONSOLE ) = {
+ .initialise = int13con_init,
+};
+
+/** INT13 console driver */
+struct console_driver int13con __console_driver = {
+ .putchar = int13con_putchar,
+ .disabled = CONSOLE_DISABLED,
+ .usage = CONSOLE_INT13,
+};
Code Review / kvmfornfv.git / blobdiff