patch-2.1.29 linux/arch/sparc64/kernel/head.S

• Lines: 192
• Date: Wed Mar 5 17:04:31 1997
• Orig file: v2.1.28/linux/arch/sparc64/kernel/head.S
• Orig date: Sun Jan 26 02:07:09 1997

diff -u --recursive --new-file v2.1.28/linux/arch/sparc64/kernel/head.S linux/arch/sparc64/kernel/head.S
@@ -1,21 +1,53 @@
-/* $Id: head.S,v 1.6 1997/01/06 20:32:44 jj Exp $
+/* $Id: head.S,v 1.9 1997/02/26 11:09:25 jj Exp $
  * head.S: Initial boot code for the Sparc64 port of Linux.
  *
  * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
+ * Copyright (C) 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
  */
 
+#include <linux/version.h>
 #include <asm/pstate.h>
+#include <asm/ptrace.h>
 #include <asm/spitfire.h>
+#include <asm/page.h>
 #include <asm/pgtable.h>
 #include <asm/errno.h>
 
-	.text
+/* This section from from _start to sparc64_boot_end should fit into
+   0xfffff80000004000 to 0xfffff80000008000 and will be sharing space
+   with bootup_user_stack, which is from 0xfffff80000004000 to
+   0xfffff80000006000 and bootup_kernel_stack, which is from
+   0xfffff80000006000 to 0xfffff80000008000. */
 
-#include "ttable.S"
+	.text
+	.globl	start, _start
+_start:
+start:
+bootup_user_stack:
+! 0xfffff80000004000
+	b	sparc64_boot
+	 rdpr	%ver, %g1			/* Get VERSION register.	*/
+
+/* This stuff has to be in sync with SILO and other potential boot loaders
+ * Fields should be kept upward compatible and whenever any change is made,
+ * HdrS version should be incremented.
+ */
+        .ascii  "HdrS"
+        .word   LINUX_VERSION_CODE
+        .half   0x0201          /* HdrS version */
+root_flags:
+        .half   1
+root_dev:
+        .half   0
+ram_flags:
+        .half   0
+ramdisk_image:
+        .word   0
+ramdisk_size:
+        .word   0
+        .word   reboot_command
 
 sparc64_boot:
-	rdpr	%ver, %g1			/* Get VERSION register.	*/
-
 	/* We must be careful, 32-bit OpenBOOT will get confused if it
 	 * tries to save away a register window to a 64-bit kernel
 	 * stack address.  Flush all windows, disable interrupts,
@@ -26,22 +58,19 @@
 	wrpr	%g0, 0xf, %pil			/* Interrupts off.           */
 
 	/* Remap ourselves to upper 64-bit addresses if necessary.
-	 * SILO64 will have loaded us to the right location already.
 	 */
-	mov	%o7, %g4
+	sethi	%uhi(PAGE_OFFSET), %g4
 current_pc:
-	call	1f
-	 mov	%o7, %g3
-1:
-	mov	%g4, %o7
-
-	set	current_pc, %g7
-	cmp	%g3, %g7
+	rd	%pc, %g2
+	sllx	%g4, 32, %g4
+	sethi	%hi(current_pc), %g3
+	or	%g3, %lo(current_pc), %g3
+	add	%g4, %g3, %g3
+	cmp	%g3, %g2
 	be	go_to_highmem
 	 nop
 
 	/* Remap ourselves into high addresses. */
-	set	PAGE_OFFSET, %g4
 	sethi	%uhi(_PAGE_VALID | _PAGE_SZ4MB), %g5
 	sllx	%g5, 32, %g5
 	or	%g5, (_PAGE_CP | _PAGE_CV | _PAGE_P | _PAGE_W | _PAGE_G | _PAGE_L), %g5
@@ -63,44 +92,84 @@
 	membar	#Sync
 	flush	%g4
 
+/* FIXME: Should clean here the page @ phys. 0 and map one page @ */
+
 go_to_highmem:
-	set	execute_in_high_mem, %g7
-	jmpl	%g7, %g0
+	jmpl	%g3 + (execute_in_high_mem - current_pc), %g0
 	 nop
 
 execute_in_high_mem:
 
-	set	nwindows, %g7
+	/* Remap our prom interface code */
+	sethi	%hi(__p1275_loc), %g7
+	or	%g7, (_PAGE_CP | _PAGE_CV | _PAGE_P | _PAGE_W | _PAGE_G | _PAGE_L), %g7
+	/* The lock bit has to be removed from this page later on, 
+	   but before firing up init we will use PROM a lot, so we
+	   lock it there now... */
+	sethi	%uhi(_PAGE_VALID), %g5
+	sethi	%hi(0x8000), %g3
+	sllx	%g5, 32, %g5
+	mov	TLB_TAG_ACCESS, %g6
+	or	%g5, %g7, %g5
+	stxa	%g3, [%g6] ASI_IMMU
+	stxa	%g5, [%g0] ASI_ITLB_DATA_IN
+	membar	#Sync
+	flush	%g3
+	stxa	%g3, [%g6] ASI_DMMU
+	stxa	%g5, [%g0] ASI_DTLB_DATA_IN
+	membar	#Sync
+	flush	%g3
+
+	sethi	%hi(nwindows), %g7
 	and	%g1, VERS_MAXWIN, %g5
-	add	%g5, 1, %g4
-	stx	%g4, [%g7]
-	set	nwindowsm1, %g6
-	stx	%g5, [%g6]
+	add	%g7, %lo(nwindows), %g7
+	add	%g5, 1, %g6
+	add	%g7, (nwindows - nwindowsm1), %g3
+	stx	%g6, [%g7 + %g4]
+	stx	%g5, [%g3 + %g4]
 	mov	%sp, %o1			! second argument to prom_init
-	set	swapper_pg_dir, %g6
-	set	PAGE_OFFSET, %g4		! this stays here for a long time
-	sub	%g6, %g4, %g5
-	set	init_task, %g6			! g6 usage is fixed as well
+	sethi	%hi(init_task), %g6
+	or	%g6, %lo(init_task), %g6
+	add	%g6, %g4, %g6			! g6 usage is fixed as well
 
-	set	sparc64_ttable_tl0, %g5
+/* FIXME: Initialize MMU globals??? */
+
+	sethi	%hi(sparc64_ttable_tl0), %g5
+	add	%g5, %g4, %g5
 	wrpr	%g5, %tba
 
-	set	bootup_kernel_stack, %sp
+	sethi	%hi(bootup_kernel_stack + 0x2000 - STACK_BIAS - REGWIN_SZ), %g5
+	or	%g5, %lo(bootup_kernel_stack + 0x2000 - STACK_BIAS - REGWIN_SZ), %g5
+	add	%g5, %g4, %sp
 	mov	0, %fp
-	wrpr	%g0, PSTATE_KERNEL, %pstate
-	wrpr	%g0, WSTATE_KERNEL, %wstate
+	wrpr	%g0, PSTATE_PEF | PSTATE_PRIV, %pstate
+	wrpr	%g0, 0, %wstate
 	wrpr	%g0, 0x0, %tl
 
-	/* XXX Map in PROM 32-bit trampoline code. */
-	
 	call	prom_init
 	 mov	%o4, %o0			! OpenPROM cif handler
 
 	/* Off we go.... */
 	call	start_kernel
 	 nop
-
 	/* Not reached... */
+
+sparc64_boot_end:
+	.skip	0x2000 + _start - sparc64_boot_end
+bootup_user_stack_end:
+
+bootup_kernel_stack:
+	.skip	0x2000
+
+! 0xfffff80000008000
+
+#include "ttable.S"
+
+        .global root_flags
+        .global ram_flags
+        .global root_dev
+        .global ramdisk_image
+        .global ramdisk_size
 
 	.data
 	.align	8