patch-2.1.30 linux/arch/sparc64/kernel/head.S

• Lines: 271
• Date: Thu Mar 20 16:43:32 1997
• Orig file: v2.1.29/linux/arch/sparc64/kernel/head.S
• Orig date: Mon Mar 17 14:54:23 1997

diff -u --recursive --new-file v2.1.29/linux/arch/sparc64/kernel/head.S linux/arch/sparc64/kernel/head.S
@@ -1,8 +1,10 @@
-/* $Id: head.S,v 1.9 1997/02/26 11:09:25 jj Exp $
+/* $Id: head.S,v 1.17 1997/03/18 17:59:37 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) 1996 David Sitsky (David.Sitsky@anu.edu.au)
  * Copyright (C) 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
+ * Copyright (C) 1997 Miguel de Icaza (miguel@nuclecu.unam.mx)
  */
 
 #include <linux/version.h>
@@ -12,12 +14,14 @@
 #include <asm/page.h>
 #include <asm/pgtable.h>
 #include <asm/errno.h>
-
+#include <asm/lsu.h>
+	
 /* 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. */
+ * 0xffff.f800.0000.4000 to 0xffff.f800.0000.8000 and will be sharing space
+ * with bootup_user_stack, which is from 0xffff.f800.0000.4000 to
+ * 0xffff.f800.0000.6000 and bootup_kernel_stack, which is from
+ * 0xffff.f800.0000.6000 to 0xffff.f800.0000.8000. 
+ */
 
 	.text
 	.globl	start, _start
@@ -26,12 +30,15 @@
 bootup_user_stack:
 ! 0xfffff80000004000
 	b	sparc64_boot
-	 rdpr	%ver, %g1			/* Get VERSION register.	*/
+	 flushw					/* Flush register file.      */
 
 /* 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.
  */
+        .global root_flags, ram_flags, root_dev
+        .global ramdisk_image, ramdisk_size
+
         .ascii  "HdrS"
         .word   LINUX_VERSION_CODE
         .half   0x0201          /* HdrS version */
@@ -47,59 +54,80 @@
         .word   0
         .word   reboot_command
 
-sparc64_boot:
 	/* 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,
 	 * remap if necessary, jump onto kernel trap table, then kernel
 	 * stack, or else we die.
+	 *
+	 * PROM entry point is on %o4
 	 */
-	flushw					/* Flush register file.      */
+sparc64_boot:
+	mov	(LSU_CONTROL_IC|LSU_CONTROL_DC|LSU_CONTROL_IM|LSU_CONTROL_DM), %g1
+	stxa	%g1, [%g0] ASI_LSU_CONTROL
+
+	/*
+	 * Make sure we are in privileged mode, have address masking,
+         * using the ordinary globals and have enabled floating
+         * point.
+         */                                                                                
+
 	wrpr	%g0, 0xf, %pil			/* Interrupts off.           */
+	wrpr    %g0, (PSTATE_PRIV|PSTATE_PEF), %pstate
 
-	/* Remap ourselves to upper 64-bit addresses if necessary.
+	/* Check if we are mapped where we expect to be in virtual
+	 * memory.  The Solaris /boot elf format bootloader
+	 * will peek into our elf header and load us where
+	 * we want to be, otherwise we have to re-map.
 	 */
-	sethi	%uhi(PAGE_OFFSET), %g4
 current_pc:
-	rd	%pc, %g2
+	rd	%pc, %g3
+	sethi	%uhi(KERNBASE), %g4
 	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. */
-	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
+	/* Check the run time program counter. */
 
-	/* Be real fucking anal... */
-	stxa	%g0, [%g4] ASI_IMMU_DEMAP
-	stxa	%g0, [%g4] ASI_DMMU_DEMAP
-	membar	#Sync
-	flush	%g4
+	set	current_pc, %g5
+	add	%g5, %g4, %g5
+	cmp	%g3, %g5
+	be	%xcc,sun4u_init
+	 nop
 
-	mov	TLB_TAG_ACCESS, %g6
-	stxa	%g4, [%g6] ASI_IMMU
-	stxa	%g5, [%g0] ASI_ITLB_DATA_IN
-	membar	#Sync
-	flush	%g4
+create_mappings:
+	/* %g5 holds the tlb data */
+        sethi   %uhi(_PAGE_VALID | _PAGE_SZ4MB), %g5
+        sllx    %g5, 32, %g5
+        or      %g5, (_PAGE_CP | _PAGE_CV | _PAGE_P | _PAGE_L | _PAGE_W | _PAGE_G), %g5
+
+	/* We aren't mapped in at KERNBASE, so we need to create
+	 * an I and D tlb entry to map KERNBASE to 0.  Both entries
+	 * are 4 Megs mappings and are locked in.
+	 */
+	set	TLB_TAG_ACCESS, %g3           /* 0x30 */
 
-	stxa	%g4, [%g6] ASI_DMMU
-	stxa	%g5, [%g0] ASI_DTLB_DATA_IN
-	membar	#Sync
-	flush	%g4
+	stxa	%g4, [%g3] ASI_IMMU           /* 0x50 */
+	stxa	%g5, [%g0] ASI_ITLB_DATA_IN   /* 0x54 */
+	membar  #Sync
+
+	/* Put KERNBASE into the I/D Tag Access Register (TAR) */
+	stxa	%g4, [%g3] ASI_DMMU           /* 0x58 */
+	stxa    %g5, [%g0] ASI_DTLB_DATA_IN
+	membar  #Sync
 
-/* FIXME: Should clean here the page @ phys. 0 and map one page @ */
+	nop
+	nop	
+	membar	#Sync
+	
+	ba,pt	%xcc, go_to_highmem
+	 nop
 
+/* Now do a non-relative jump so that PC is in high-memory */
 go_to_highmem:
-	jmpl	%g3 + (execute_in_high_mem - current_pc), %g0
+	set	sun4u_init, %g1
+	jmpl     %g1 + %g4, %g0
 	 nop
 
-execute_in_high_mem:
-
+sun4u_init:
 	/* 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
@@ -114,29 +142,40 @@
 	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	%g7, %lo(nwindows), %g7
+	nop
+	nop
+	membar	#Sync
+	
+	/* Compute the number of windows in this machine
+	 * store this in nwindows and nwindowsm1
+	 */
+	rdpr	%ver, %g1			/* Get VERSION register.	*/
+	sethi   %hi(nwindows), %g2
+	and     %g1, VERS_MAXWIN, %g5
+	or	%g2,%lo(nwindows),%g2
 	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
+	add	%g2, (nwindows - nwindowsm1), %g3
+	stx     %g6, [%g2 + %g4]
+	stx     %g5, [%g3 + %g4]
+
 	sethi	%hi(init_task), %g6
 	or	%g6, %lo(init_task), %g6
 	add	%g6, %g4, %g6			! g6 usage is fixed as well
+	mov	%sp, %l6
+	mov	%o4, %l7
 
-/* FIXME: Initialize MMU globals??? */
-
+#if 0
+/* This is to dangerous for now... To many traps unfilled yet... */
 	sethi	%hi(sparc64_ttable_tl0), %g5
 	add	%g5, %g4, %g5
 	wrpr	%g5, %tba
+#endif
 
 	sethi	%hi(bootup_kernel_stack + 0x2000 - STACK_BIAS - REGWIN_SZ), %g5
 	or	%g5, %lo(bootup_kernel_stack + 0x2000 - STACK_BIAS - REGWIN_SZ), %g5
@@ -145,9 +184,36 @@
 	wrpr	%g0, PSTATE_PEF | PSTATE_PRIV, %pstate
 	wrpr	%g0, 0, %wstate
 	wrpr	%g0, 0x0, %tl
+	fzero	%f48
+	fzero	%f50
+	fzero	%f52
+	fzero	%f54
+	fzero	%f56
+	fzero	%f58
+	fzero	%f60
+	fzero	%f62
+
+	/* Clear the bss */
+	sethi	%hi(8191), %l2
+	or	%l2, %lo(8191), %l2
+	sethi	%hi(__bss_start), %l0
+	or	%l0, %lo(__bss_start), %l0
+	sethi	%hi(_end), %l1
+	or	%l1, %lo(_end), %l1
+	add	%l1, %l2, %l1
+	andn	%l1, %l2, %l1
+	add	%l2, 1, %l2
+	add	%l0, %g4, %o0
+1:
+	call	bzero_1page
+	 add	%l0, %l2, %l0
+	cmp	%l0, %l1
+	blu,pt	%xcc, 1b
+	 add	%l0, %g4, %o0
 
+	mov	%l6, %o1			! OpenPROM stack
 	call	prom_init
-	 mov	%o4, %o0			! OpenPROM cif handler
+	 mov	%l7, %o0			! OpenPROM cif handler
 
 	/* Off we go.... */
 	call	start_kernel
@@ -165,18 +231,11 @@
 
 #include "ttable.S"
 
-        .global root_flags
-        .global ram_flags
-        .global root_dev
-        .global ramdisk_image
-        .global ramdisk_size
-
 	.data
 	.align	8
 	.globl	nwindows, nwindowsm1 
 nwindows:	.xword	0
 nwindowsm1:	.xword	0
-
 	.section	".fixup",#alloc,#execinstr
 	.globl	__ret_efault
 __ret_efault: