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-rw-r--r--qemu/roms/vgabios/biossums.c282
1 files changed, 282 insertions, 0 deletions
diff --git a/qemu/roms/vgabios/biossums.c b/qemu/roms/vgabios/biossums.c
new file mode 100644
index 000000000..d5816f420
--- /dev/null
+++ b/qemu/roms/vgabios/biossums.c
@@ -0,0 +1,282 @@
+/* biossums.c --- written by Eike W. for the Bochs BIOS */
+/* adapted for the LGPL'd VGABIOS by vruppert */
+
+/* This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+typedef unsigned char byte;
+
+void check( int value, char* message );
+
+#define MAX_BIOS_DATA 0x10000
+
+long chksum_bios_get_offset( byte* data, long offset );
+byte chksum_bios_calc_value( byte* data, long offset );
+byte chksum_bios_get_value( byte* data, long offset );
+void chksum_bios_set_value( byte* data, long offset, byte value );
+
+#define PMID_LEN 20
+#define PMID_CHKSUM 19
+
+long chksum_pmid_get_offset( byte* data, long offset );
+byte chksum_pmid_calc_value( byte* data, long offset );
+byte chksum_pmid_get_value( byte* data, long offset );
+void chksum_pmid_set_value( byte* data, long offset, byte value );
+
+#define PCIR_LEN 24
+
+long chksum_pcir_get_offset( byte* data, long offset );
+
+
+byte bios_data[MAX_BIOS_DATA];
+long bios_len;
+
+
+int main(int argc, char* argv[])
+{
+ FILE* stream;
+ long offset, tmp_offset, pcir_offset;
+ byte bios_len_byte, cur_val = 0, new_val = 0;
+ int hits, modified;
+
+ if (argc != 2) {
+ printf( "Error. Need a file-name as an argument.\n" );
+ exit( EXIT_FAILURE );
+ }
+
+ if ((stream = fopen(argv[1], "rb")) == NULL) {
+ printf("Error opening %s for reading.\n", argv[1]);
+ exit(EXIT_FAILURE);
+ }
+ memset(bios_data, 0, MAX_BIOS_DATA);
+ bios_len = fread(bios_data, 1, MAX_BIOS_DATA, stream);
+ if (bios_len > MAX_BIOS_DATA) {
+ printf("Error reading max. 65536 Bytes from %s.\n", argv[1]);
+ fclose(stream);
+ exit(EXIT_FAILURE);
+ }
+ fclose(stream);
+ modified = 0;
+ if (bios_len < 0x8000) {
+ bios_len = 0x8000;
+ modified = 1;
+ } else if ((bios_len & 0x1FF) != 0) {
+ bios_len = (bios_len + 0x200) & ~0x1FF;
+ modified = 1;
+ }
+ bios_len_byte = (byte)(bios_len / 512);
+ if (bios_len_byte != bios_data[2]) {
+ if (modified == 0) {
+ bios_len += 0x200;
+ }
+ bios_data[2] = (byte)(bios_len / 512);
+ modified = 1;
+ }
+
+ hits = 0;
+ offset = 0L;
+ while( (tmp_offset = chksum_pmid_get_offset( bios_data, offset )) != -1L ) {
+ offset = tmp_offset;
+ cur_val = chksum_pmid_get_value( bios_data, offset );
+ new_val = chksum_pmid_calc_value( bios_data, offset );
+ printf( "\nPMID entry at: 0x%4lX\n", offset );
+ printf( "Current checksum: 0x%02X\n", cur_val );
+ printf( "Calculated checksum: 0x%02X ", new_val );
+ hits++;
+ }
+ if ((hits == 1) && (cur_val != new_val)) {
+ printf("Setting checksum.");
+ chksum_pmid_set_value( bios_data, offset, new_val );
+ if (modified == 0) {
+ bios_len += 0x200;
+ bios_data[2]++;
+ }
+ modified = 1;
+ }
+ if (hits >= 2) {
+ printf( "Multiple PMID entries! No checksum set." );
+ }
+ if (hits) {
+ printf("\n");
+ }
+
+ offset = 0L;
+ pcir_offset = chksum_pcir_get_offset( bios_data, offset );
+ if (pcir_offset != -1L) {
+ if (bios_data[pcir_offset + 16] != bios_data[2]) {
+ bios_data[pcir_offset + 16] = bios_data[2];
+ if (modified == 0) {
+ bios_len += 0x200;
+ bios_data[2]++;
+ bios_data[pcir_offset + 16]++;
+ }
+ modified = 1;
+ }
+ }
+
+ offset = 0L;
+ do {
+ offset = chksum_bios_get_offset(bios_data, offset);
+ cur_val = chksum_bios_get_value(bios_data, offset);
+ new_val = chksum_bios_calc_value(bios_data, offset);
+ if ((cur_val != new_val) && (modified == 0)) {
+ bios_len += 0x200;
+ bios_data[2]++;
+ if (pcir_offset != -1L) {
+ bios_data[pcir_offset + 16]++;
+ }
+ modified = 1;
+ } else {
+ printf("\nBios checksum at: 0x%4lX\n", offset);
+ printf("Current checksum: 0x%02X\n", cur_val);
+ printf("Calculated checksum: 0x%02X ", new_val);
+ if (cur_val != new_val) {
+ printf("Setting checksum.");
+ chksum_bios_set_value(bios_data, offset, new_val);
+ cur_val = new_val;
+ modified = 1;
+ }
+ printf( "\n" );
+ }
+ } while (cur_val != new_val);
+
+ if (modified == 1) {
+ if ((stream = fopen( argv[1], "wb")) == NULL) {
+ printf("Error opening %s for writing.\n", argv[1]);
+ exit(EXIT_FAILURE);
+ }
+ if (fwrite(bios_data, 1, bios_len, stream) < bios_len) {
+ printf("Error writing %d KBytes to %s.\n", bios_len / 1024, argv[1]);
+ fclose(stream);
+ exit(EXIT_FAILURE);
+ }
+ fclose(stream);
+ }
+
+ return (EXIT_SUCCESS);
+}
+
+
+void check( int okay, char* message ) {
+
+ if( !okay ) {
+ printf( "\n\nError. %s.\n", message );
+ exit( EXIT_FAILURE );
+ }
+}
+
+
+long chksum_bios_get_offset( byte* data, long offset ) {
+
+ return (bios_len - 1);
+}
+
+
+byte chksum_bios_calc_value( byte* data, long offset ) {
+
+ int i;
+ byte sum;
+
+ sum = 0;
+ for( i = 0; i < offset; i++ ) {
+ sum = sum + *( data + i );
+ }
+ sum = -sum; /* iso ensures -s + s == 0 on unsigned types */
+ return( sum );
+}
+
+
+byte chksum_bios_get_value( byte* data, long offset ) {
+
+ return( *( data + offset ) );
+}
+
+
+void chksum_bios_set_value( byte* data, long offset, byte value ) {
+
+ *( data + offset ) = value;
+}
+
+
+byte chksum_pmid_calc_value( byte* data, long offset ) {
+
+ int i;
+ int len;
+ byte sum;
+
+ len = PMID_LEN;
+ check((offset + len) <= (bios_len - 1), "PMID entry length out of bounds" );
+ sum = 0;
+ for( i = 0; i < len; i++ ) {
+ if( i != PMID_CHKSUM ) {
+ sum = sum + *( data + offset + i );
+ }
+ }
+ sum = -sum;
+ return( sum );
+}
+
+
+long chksum_pmid_get_offset( byte* data, long offset ) {
+
+ long result = -1L;
+
+ while ((offset + PMID_LEN) < (bios_len - 1)) {
+ offset = offset + 1;
+ if( *( data + offset + 0 ) == 'P' && \
+ *( data + offset + 1 ) == 'M' && \
+ *( data + offset + 2 ) == 'I' && \
+ *( data + offset + 3 ) == 'D' ) {
+ result = offset;
+ break;
+ }
+ }
+ return( result );
+}
+
+
+byte chksum_pmid_get_value( byte* data, long offset ) {
+
+ check((offset + PMID_CHKSUM) <= (bios_len - 1), "PMID checksum out of bounds" );
+ return( *( data + offset + PMID_CHKSUM ) );
+}
+
+
+void chksum_pmid_set_value( byte* data, long offset, byte value ) {
+
+ check((offset + PMID_CHKSUM) <= (bios_len - 1), "PMID checksum out of bounds" );
+ *( data + offset + PMID_CHKSUM ) = value;
+}
+
+
+long chksum_pcir_get_offset( byte* data, long offset ) {
+
+ long result = -1L;
+
+ while ((offset + PCIR_LEN) < (bios_len - 1)) {
+ offset = offset + 1;
+ if( *( data + offset + 0 ) == 'P' && \
+ *( data + offset + 1 ) == 'C' && \
+ *( data + offset + 2 ) == 'I' && \
+ *( data + offset + 3 ) == 'R' ) {
+ result = offset;
+ break;
+ }
+ }
+ return( result );
+}