Changeset 32 for trunk/hal/x86_64/hal_boot.S

Timestamp:

Jun 21, 2017, 11:34:09 AM (7 years ago)

Author:

max@…

Message:

Update. Retrieve and parse the multiboot info, and dump the mmap. Some
more sanity checks could probably be added.

File:

• trunk/hal/x86_64/hal_boot.S (modified) (6 diffs)

trunk/hal/x86_64/hal_boot.S

@@ -24 +24 @@
 #define x86_ASM
 #include <hal_boot.h>
+#include <hal_multiboot.h>
 #include <hal_register.h>
 #include <hal_segmentation.h>
@@ -181 +182 @@
         /* Warm boot */
         movw    $0x1234,0x472
+        cld
 
         /* Make sure it is a multiboot-compliant bootloader. */
-//      cmpl    $MULTIBOOT_INFO_MAGIC,%eax
-//      jne     boot_panic
+        cmpl    $MULTIBOOT_INFO_MAGIC,%eax
+        je      1f
+        ret     /* what to do? */
+1:
 
         movl    $RELOC(tmpstk),%esp
@@ -192 +196 @@
         popfl
 
+        /*
+         * Copy the various multiboot structures
+         */
+        movl    %ebx,%esi                       /* src */
+        movl    $RELOC(mb_info),%edi            /* dst */
+        movl    $MULTIBOOT_INFO_SIZE,%ecx       /* len */
+        rep
+        movsb   /* copy esi -> edi */
+
+        testl   $MULTIBOOT_INFO_HAS_LOADER_NAME,MB_MI_FLAGS(%ebx)
+        jz      1f
+        movl    MB_MI_LOADER_NAME(%ebx),%esi    /* src */
+        movl    $RELOC(mb_loader_name),%edi     /* dst */
+copy_loop:
+        cmpb    $0,(%esi)
+        je      copy_end
+        movsb   /* copy esi -> edi */
+        jmp     copy_loop
+copy_end:
+        movsb   /* copy esi -> edi */
+1:
+
+        testl   $MULTIBOOT_INFO_HAS_MMAP,MB_MI_FLAGS(%ebx)
+        jz      1f
+        movl    MB_MI_MMAP_ADDR(%ebx),%esi      /* src */
+        movl    $RELOC(mb_mmap),%edi            /* dst */
+        movl    MB_MI_MMAP_LENGTH(%ebx),%ecx    /* len */
+
+        rep
+        movsb   /* copy esi -> edi */
+1:
+
 /*
  * There are four levels of pages in amd64: PML4 -> PDP -> PD -> PT. They will
@@ -197 +233 @@
  *
  * Virtual address space of the kernel:
- * +---------------+------------+-----------------------------------+---
- * | TEXT + RODATA | DATA + BSS | L4 -> PROC0 STK -> L3 -> L2 -> L1 |
- * +---------------+------------+-----------------------------------+---
- *                             (1)
- *
- * ---+-------------+
- *    | ISA I/O MEM |
- * ---+-------------+
- *   (2)
+ * +---------------+------+-----------------------------------+-------------+
+ * | TEXT + RODATA | DATA | L4 -> PROC0 STK -> L3 -> L2 -> L1 | ISA I/O MEM |
+ * +---------------+------+-----------------------------------+-------------+
+ *                       (1)                                 (2)
  *
  * PROC0 STK is obviously not linked as a page level. It just happens to be
@@ -215 +246 @@
  *
  * Important note: the kernel segments are properly 4k-aligned
- * (see kern.ldscript), so there's no need to enforce alignment.
+ * (see kernel_x86.ld), so there's no need to enforce alignment.
  */
 
@@ -430 +461 @@
         killkpt
 
-        /* Relocate atdevbase. */
+        /* Save the virtual address of ISA I/O MEM. */
         movq    $(TABLESIZE+KERNBASE),%rdx
         addq    %rsi,%rdx