Changeset babcb148 in mainline for arch/ia32/src/smp/mp.c

Timestamp:

2005-04-27T21:19:42Z (20 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

10a2e22

Parents:

434f700

Message:

ACPI detection code.
MP detection code rewrite.
Minor changes.

File:

• arch/ia32/src/smp/mp.c (modified) (2 diffs)

arch/ia32/src/smp/mp.c

@@ -129 +129 @@
 void mp_init(void)
 {
-        __address addr, frame;
-        int cnt, n;
-        
-
-        /*
-         * EBDA can be undefined. In that case addr would be 0. 
-         */
-        addr = ebda;
-        if (addr) {
-                cnt = 1024;
-                while (addr = __u32_search(addr,cnt,FS_SIGNATURE)) {
-                        if (mp_fs_check((__u8 *) addr))
+        __u8 *addr[2] = { NULL, (__u8 *) 0xf0000 };
+        int i, j, length[2] = { 1024, 64*1024 };
+        
+
+        /*
+         * Find MP Floating Pointer Structure
+         * 1a. search first 1K of EBDA
+         * 1b. if EBDA is undefined, search last 1K of base memory
+         *  2. search 64K starting at 0xf0000
+         */
+
+        addr[0] = (__u8 *) (ebda ? ebda : 639 * 1024);
+        for (i = 0; i < 2; i++) {
+                for (j = 0; j < length[i]; j += 16) {
+                        if (*((__u32 *) &addr[i][j]) == FS_SIGNATURE && mp_fs_check(&addr[i][j])) {
+                                fs = (struct __mpfs *) &addr[i][j];
                                 goto fs_found;
-                        addr++;
-                        cnt--;
-                }
-        }
-        else {
-                /*
-                 * Second place where the MP Floating Pointer Structure may live is the last
-                 * kilobyte of base memory.
-                 */
-                addr = 639*1024;
-                cnt = 1024;
-                while (addr = __u32_search(addr,cnt,FS_SIGNATURE)) {
-                        if (mp_fs_check((__u8 *) addr))
-                                goto fs_found;
-                        addr++;
-                        cnt--;
-                }
-        }
-
-        /*
-         * As the last resort, MP Floating Pointer Structure is searched in the BIOS
-         * ROM.
-         */
-        addr = 0xf0000;
-        cnt = 64*1024;
-        while (addr = __u32_search(addr,cnt,FS_SIGNATURE)) {
-                if (mp_fs_check((__u8 *) addr))
-                        goto fs_found;
-                addr++;
-                cnt--;
+                        }
+                }
         }
 
@@ -177 +153 @@
         
 fs_found:
-        printf("%L: MP Floating Pointer Structure\n", addr);
-
-        fs = (struct __mpfs *) addr;
+        printf("%L: MP Floating Pointer Structure\n", fs);
+
         frame_not_free((__address) fs);
-        
+
         if (fs->config_type == 0 && fs->configuration_table) {
                 if (fs->mpfib2 >> 7) {