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+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1994, 1995 Waldorf Electronics
+ * Written by Ralf Baechle and Andreas Busse
+ * Copyright (C) 1994, 95, 96, 97, 98, 99, 2003 Ralf Baechle
+ * Copyright (C) 1996 Paul M. Antoine
+ * Modified for DECStation and hence R3000 support by Paul M. Antoine
+ * Further modifications by David S. Miller and Harald Koerfgen
+ * Copyright (C) 1999 Silicon Graphics, Inc.
+ * Kevin Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
+ * Copyright (C) 2000 MIPS Technologies, Inc. All rights reserved.
+ */
+#include <linux/config.h>
+#include <linux/init.h>
+#include <linux/threads.h>
+
+#include <asm/asm.h>
+#include <asm/regdef.h>
+#include <asm/page.h>
+#include <asm/mipsregs.h>
+#include <asm/stackframe.h>
+#ifdef CONFIG_SGI_IP27
+#include <asm/sn/addrs.h>
+#include <asm/sn/sn0/hubni.h>
+#include <asm/sn/klkernvars.h>
+#endif
+
+ .macro ARC64_TWIDDLE_PC
+#if defined(CONFIG_ARC64) || defined(CONFIG_MAPPED_KERNEL)
+ /* We get launched at a XKPHYS address but the kernel is linked to
+ run at a KSEG0 address, so jump there. */
+ PTR_LA t0, \@f
+ jr t0
+\@:
+#endif
+ .endm
+
+#ifdef CONFIG_SGI_IP27
+ /*
+ * outputs the local nasid into res. IP27 stuff.
+ */
+ .macro GET_NASID_ASM res
+ dli \res, LOCAL_HUB_ADDR(NI_STATUS_REV_ID)
+ ld \res, (\res)
+ and \res, NSRI_NODEID_MASK
+ dsrl \res, NSRI_NODEID_SHFT
+ .endm
+#endif /* CONFIG_SGI_IP27 */
+
+ /*
+ * inputs are the text nasid in t1, data nasid in t2.
+ */
+ .macro MAPPED_KERNEL_SETUP_TLB
+#ifdef CONFIG_MAPPED_KERNEL
+ /*
+ * This needs to read the nasid - assume 0 for now.
+ * Drop in 0xffffffffc0000000 in tlbhi, 0+VG in tlblo_0,
+ * 0+DVG in tlblo_1.
+ */
+ dli t0, 0xffffffffc0000000
+ dmtc0 t0, CP0_ENTRYHI
+ li t0, 0x1c000 # Offset of text into node memory
+ dsll t1, NASID_SHFT # Shift text nasid into place
+ dsll t2, NASID_SHFT # Same for data nasid
+ or t1, t1, t0 # Physical load address of kernel text
+ or t2, t2, t0 # Physical load address of kernel data
+ dsrl t1, 12 # 4K pfn
+ dsrl t2, 12 # 4K pfn
+ dsll t1, 6 # Get pfn into place
+ dsll t2, 6 # Get pfn into place
+ li t0, ((_PAGE_GLOBAL|_PAGE_VALID| _CACHE_CACHABLE_COW) >> 6)
+ or t0, t0, t1
+ mtc0 t0, CP0_ENTRYLO0 # physaddr, VG, cach exlwr
+ li t0, ((_PAGE_GLOBAL|_PAGE_VALID| _PAGE_DIRTY|_CACHE_CACHABLE_COW) >> 6)
+ or t0, t0, t2
+ mtc0 t0, CP0_ENTRYLO1 # physaddr, DVG, cach exlwr
+ li t0, 0x1ffe000 # MAPPED_KERN_TLBMASK, TLBPGMASK_16M
+ mtc0 t0, CP0_PAGEMASK
+ li t0, 0 # KMAP_INX
+ mtc0 t0, CP0_INDEX
+ li t0, 1
+ mtc0 t0, CP0_WIRED
+ tlbwi
+#else
+ mtc0 zero, CP0_WIRED
+#endif
+ .endm
+
+ /*
+ * For the moment disable interrupts, mark the kernel mode and
+ * set ST0_KX so that the CPU does not spit fire when using
+ * 64-bit addresses. A full initialization of the CPU's status
+ * register is done later in per_cpu_trap_init().
+ */
+ .macro setup_c0_status set clr
+ .set push
+ mfc0 t0, CP0_STATUS
+ or t0, ST0_CU0|\set|0x1f|\clr
+ xor t0, 0x1f|\clr
+ mtc0 t0, CP0_STATUS
+ .set noreorder
+ sll zero,3 # ehb
+ .set pop
+ .endm
+
+ .macro setup_c0_status_pri
+#ifdef CONFIG_MIPS64
+ setup_c0_status ST0_KX 0
+#else
+ setup_c0_status 0 0
+#endif
+ .endm
+
+ .macro setup_c0_status_sec
+#ifdef CONFIG_MIPS64
+ setup_c0_status ST0_KX ST0_BEV
+#else
+ setup_c0_status 0 ST0_BEV
+#endif
+ .endm
+
+ /*
+ * Reserved space for exception handlers.
+ * Necessary for machines which link their kernels at KSEG0.
+ */
+ .fill 0x400
+
+EXPORT(stext) # used for profiling
+EXPORT(_stext)
+
+ __INIT
+
+NESTED(kernel_entry, 16, sp) # kernel entry point
+ setup_c0_status_pri
+
+#ifdef CONFIG_SGI_IP27
+ GET_NASID_ASM t1
+ move t2, t1 # text and data are here
+ MAPPED_KERNEL_SETUP_TLB
+#endif /* IP27 */
+
+ ARC64_TWIDDLE_PC
+
+ PTR_LA t0, __bss_start # clear .bss
+ LONG_S zero, (t0)
+ PTR_LA t1, __bss_stop - LONGSIZE
+1:
+ PTR_ADDIU t0, LONGSIZE
+ LONG_S zero, (t0)
+ bne t0, t1, 1b
+
+ LONG_S a0, fw_arg0 # firmware arguments
+ LONG_S a1, fw_arg1
+ LONG_S a2, fw_arg2
+ LONG_S a3, fw_arg3
+
+ PTR_LA $28, init_thread_union
+ PTR_ADDIU sp, $28, _THREAD_SIZE - 32
+ set_saved_sp sp, t0, t1
+ PTR_SUBU sp, 4 * SZREG # init stack pointer
+
+ j start_kernel
+ END(kernel_entry)
+
+#ifdef CONFIG_SMP
+/*
+ * SMP slave cpus entry point. Board specific code for bootstrap calls this
+ * function after setting up the stack and gp registers.
+ */
+NESTED(smp_bootstrap, 16, sp)
+ setup_c0_status_sec
+
+#ifdef CONFIG_SGI_IP27
+ GET_NASID_ASM t1
+ dli t0, KLDIR_OFFSET + (KLI_KERN_VARS * KLDIR_ENT_SIZE) + \
+ KLDIR_OFF_POINTER + CAC_BASE
+ dsll t1, NASID_SHFT
+ or t0, t0, t1
+ ld t0, 0(t0) # t0 points to kern_vars struct
+ lh t1, KV_RO_NASID_OFFSET(t0)
+ lh t2, KV_RW_NASID_OFFSET(t0)
+ MAPPED_KERNEL_SETUP_TLB
+ ARC64_TWIDDLE_PC
+#endif /* CONFIG_SGI_IP27 */
+
+ j start_secondary
+ END(smp_bootstrap)
+#endif /* CONFIG_SMP */
+
+ __FINIT
+
+ .comm kernelsp, NR_CPUS * 8, 8
+ .comm pgd_current, NR_CPUS * 8, 8
+
+ .comm fw_arg0, SZREG, SZREG # firmware arguments
+ .comm fw_arg1, SZREG, SZREG
+ .comm fw_arg2, SZREG, SZREG
+ .comm fw_arg3, SZREG, SZREG
+
+ .macro page name, order=0
+ .globl \name
+\name: .size \name, (_PAGE_SIZE << \order)
+ .org . + (_PAGE_SIZE << \order)
+ .type \name, @object
+ .endm
+
+ .data
+ .align PAGE_SHIFT
+
+ /*
+ * ... but on 64-bit we've got three-level pagetables with a
+ * slightly different layout ...
+ */
+ page swapper_pg_dir, _PGD_ORDER
+#ifdef CONFIG_MIPS64
+ page invalid_pmd_table, _PMD_ORDER
+#endif
+ page invalid_pte_table, _PTE_ORDER
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