xref: /linux/arch/mips/include/asm/mach-ip27/kernel-entry-init.h (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2000 Silicon Graphics, Inc.
7  * Copyright (C) 2005 Ralf Baechle <ralf@linux-mips.org>
8  */
9 #ifndef __ASM_MACH_IP27_KERNEL_ENTRY_H
10 #define __ASM_MACH_IP27_KERNEL_ENTRY_H
11 
12 #include <asm/sn/addrs.h>
13 #include <asm/sn/agent.h>
14 #include <asm/sn/klkernvars.h>
15 
16 /*
17  * TLB bits
18  */
19 #define PAGE_GLOBAL		(1 << 6)
20 #define PAGE_VALID		(1 << 7)
21 #define PAGE_DIRTY		(1 << 8)
22 #define CACHE_CACHABLE_COW	(5 << 9)
23 
24 	/*
25 	 * inputs are the text nasid in t1, data nasid in t2.
26 	 */
27 	.macro MAPPED_KERNEL_SETUP_TLB
28 #ifdef CONFIG_MAPPED_KERNEL
29 	/*
30 	 * This needs to read the nasid - assume 0 for now.
31 	 * Drop in 0xffffffffc0000000 in tlbhi, 0+VG in tlblo_0,
32 	 * 0+DVG in tlblo_1.
33 	 */
34 	dli	t0, 0xffffffffc0000000
35 	dmtc0	t0, CP0_ENTRYHI
36 	li	t0, 0x1c000		# Offset of text into node memory
37 	dsll	t1, NASID_SHFT		# Shift text nasid into place
38 	dsll	t2, NASID_SHFT		# Same for data nasid
39 	or	t1, t1, t0		# Physical load address of kernel text
40 	or	t2, t2, t0		# Physical load address of kernel data
41 	dsrl	t1, 12			# 4K pfn
42 	dsrl	t2, 12			# 4K pfn
43 	dsll	t1, 6			# Get pfn into place
44 	dsll	t2, 6			# Get pfn into place
45 	li	t0, ((PAGE_GLOBAL | PAGE_VALID | CACHE_CACHABLE_COW) >> 6)
46 	or	t0, t0, t1
47 	mtc0	t0, CP0_ENTRYLO0	# physaddr, VG, cach exlwr
48 	li	t0, ((PAGE_GLOBAL | PAGE_VALID |  PAGE_DIRTY | CACHE_CACHABLE_COW) >> 6)
49 	or	t0, t0, t2
50 	mtc0	t0, CP0_ENTRYLO1	# physaddr, DVG, cach exlwr
51 	li	t0, 0x1ffe000		# MAPPED_KERN_TLBMASK, TLBPGMASK_16M
52 	mtc0	t0, CP0_PAGEMASK
53 	li	t0, 0			# KMAP_INX
54 	mtc0	t0, CP0_INDEX
55 	li	t0, 1
56 	mtc0	t0, CP0_WIRED
57 	tlbwi
58 #else
59 	mtc0	zero, CP0_WIRED
60 #endif
61 	.endm
62 
63 /*
64  * Intentionally empty macro, used in head.S. Override in
65  * arch/mips/mach-xxx/kernel-entry-init.h when necessary.
66  */
67 	.macro	kernel_entry_setup
68 	GET_NASID_ASM	t1
69 	move		t2, t1			# text and data are here
70 	MAPPED_KERNEL_SETUP_TLB
71 	.endm
72 
73 /*
74  * Do SMP slave processor setup necessary before we can safely execute C code.
75  */
76 	.macro	smp_slave_setup
77 	GET_NASID_ASM	t1
78 	dli	t0, KLDIR_OFFSET + (KLI_KERN_VARS * KLDIR_ENT_SIZE) + \
79 		    KLDIR_OFF_POINTER + CAC_BASE
80 	dsll	t1, NASID_SHFT
81 	or	t0, t0, t1
82 	ld	t0, 0(t0)			# t0 points to kern_vars struct
83 	lh	t1, KV_RO_NASID_OFFSET(t0)
84 	lh	t2, KV_RW_NASID_OFFSET(t0)
85 	MAPPED_KERNEL_SETUP_TLB
86 
87 	/*
88 	 * We might not get launched at the address the kernel is linked to,
89 	 * so we jump there.
90 	 */
91 	PTR_LA	t0, 0f
92 	jr	t0
93 0:
94 	.endm
95 
96 #endif /* __ASM_MACH_IP27_KERNEL_ENTRY_H */
97