Changeset 84060e2 in mainline for kernel/arch/sparc64/src/start.S

Timestamp:

2006-10-09T19:29:42Z (18 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

8ce8499

Parents:

e4398200

Message:

sparc64 work:

• hw_map() can now support up to 8M requests
• CPU stacks are now locked in DTLB of the respective processor
• kernel in the boot phase no longer relies on the stack provided by OpenFirmware
• instead of of doing FLUSHW during kernel startup, simply set the window state registers to the wanted state
• NWINDOW → NWINDOWS
• Add/fix some comments and copyrights.

File:

• kernel/arch/sparc64/src/start.S (modified) (5 diffs)

kernel/arch/sparc64/src/start.S

@@ -30 +30 @@
 #include <arch/regdef.h>
 #include <arch/boot/boot.h>
+#include <arch/stack.h>
 
 #include <arch/mm/mmu.h>
@@ -57 +58 @@
  * - TLBs are on
  * - identity mapping for the kernel image
- * - identity mapping for memory stack
  */
 
@@ -68 +68 @@
          */
 
-        flushw                                  ! flush all but the active register window
+        wrpr %g0, NWINDOWS - 2, %cansave                ! set maximum saveable windows
+        wrpr %g0, 0, %canrestore                ! get rid of windows we will never need again
+        wrpr %g0, 0, %otherwin                  ! make sure the window state is consistent
+        wrpr %g0, NWINDOWS - 1, %cleanwin       ! prevent needless clean_window traps for kernel
 
         wrpr %g0, 0, %tl                        ! TL = 0, primary context register is used
@@ -216 +219 @@
         nop
 
+        /*
+         * So far, we have not touched the stack.
+         * It is a good idead to set the kernel stack to a known state now.
+         */
+        sethi %hi(temporary_boot_stack), %sp
+        or %sp, %lo(temporary_boot_stack), %sp
+        sub %sp, STACK_BIAS, %sp
+
         sethi %hi(bootinfo), %o0
         call memcpy                             ! copy bootinfo
@@ -273 +284 @@
         ba 0b
         nop
+
+
+.section K_DATA_START, "aw", @progbits
+
+/*
+ * Create small stack to be used by the bootstrap processor.
+ * It is going to be used only for a very limited period of
+ * time, but we switch to it anyway, just to be sure we are
+ * properly initialized.
+ *
+ * What is important is that this piece of memory is covered
+ * by the 4M DTLB locked entry and therefore there will be
+ * no surprises like deadly combinations of spill trap and
+ * and TLB miss on the stack address.
+ */
+
+#define INITIAL_STACK_SIZE      1024
+
+.align STACK_ALIGNMENT
+.space INITIAL_STACK_SIZE
+.align STACK_ALIGNMENT
+temporary_boot_stack:
+.space STACK_WINDOW_SAVE_AREA_SIZE