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/sn0/hubni.h>
14 #include <asm/sn/klkernvars.h>
15 
16 /*
17  * Returns the local nasid into res.
18  */
19 	.macro GET_NASID_ASM res
20 	dli	\res, LOCAL_HUB_ADDR(NI_STATUS_REV_ID)
21 	ld	\res, (\res)
22 	and	\res, NSRI_NODEID_MASK
23 	dsrl	\res, NSRI_NODEID_SHFT
24 	.endm
25 
26 /*
27  * TLB bits
28  */
29 #define PAGE_GLOBAL		(1 << 6)
30 #define PAGE_VALID		(1 << 7)
31 #define PAGE_DIRTY		(1 << 8)
32 #define CACHE_CACHABLE_COW	(5 << 9)
33 
34 	/*
35 	 * inputs are the text nasid in t1, data nasid in t2.
36 	 */
37 	.macro MAPPED_KERNEL_SETUP_TLB
38 #ifdef CONFIG_MAPPED_KERNEL
39 	/*
40 	 * This needs to read the nasid - assume 0 for now.
41 	 * Drop in 0xffffffffc0000000 in tlbhi, 0+VG in tlblo_0,
42 	 * 0+DVG in tlblo_1.
43 	 */
44 	dli	t0, 0xffffffffc0000000
45 	dmtc0	t0, CP0_ENTRYHI
46 	li	t0, 0x1c000		# Offset of text into node memory
47 	dsll	t1, NASID_SHFT		# Shift text nasid into place
48 	dsll	t2, NASID_SHFT		# Same for data nasid
49 	or	t1, t1, t0		# Physical load address of kernel text
50 	or	t2, t2, t0		# Physical load address of kernel data
51 	dsrl	t1, 12			# 4K pfn
52 	dsrl	t2, 12			# 4K pfn
53 	dsll	t1, 6			# Get pfn into place
54 	dsll	t2, 6			# Get pfn into place
55 	li	t0, ((PAGE_GLOBAL | PAGE_VALID | CACHE_CACHABLE_COW) >> 6)
56 	or	t0, t0, t1
57 	mtc0	t0, CP0_ENTRYLO0	# physaddr, VG, cach exlwr
58 	li	t0, ((PAGE_GLOBAL | PAGE_VALID |  PAGE_DIRTY | CACHE_CACHABLE_COW) >> 6)
59 	or	t0, t0, t2
60 	mtc0	t0, CP0_ENTRYLO1	# physaddr, DVG, cach exlwr
61 	li	t0, 0x1ffe000		# MAPPED_KERN_TLBMASK, TLBPGMASK_16M
62 	mtc0	t0, CP0_PAGEMASK
63 	li	t0, 0			# KMAP_INX
64 	mtc0	t0, CP0_INDEX
65 	li	t0, 1
66 	mtc0	t0, CP0_WIRED
67 	tlbwi
68 #else
69 	mtc0	zero, CP0_WIRED
70 #endif
71 	.endm
72 
73 /*
74  * Intentionally empty macro, used in head.S. Override in
75  * arch/mips/mach-xxx/kernel-entry-init.h when necessary.
76  */
77 	.macro	kernel_entry_setup
78 	GET_NASID_ASM	t1
79 	move		t2, t1			# text and data are here
80 	MAPPED_KERNEL_SETUP_TLB
81 	.endm
82 
83 /*
84  * Do SMP slave processor setup necessary before we can savely execute C code.
85  */
86 	.macro	smp_slave_setup
87 	GET_NASID_ASM	t1
88 	dli	t0, KLDIR_OFFSET + (KLI_KERN_VARS * KLDIR_ENT_SIZE) + \
89 		    KLDIR_OFF_POINTER + CAC_BASE
90 	dsll	t1, NASID_SHFT
91 	or	t0, t0, t1
92 	ld	t0, 0(t0)			# t0 points to kern_vars struct
93 	lh	t1, KV_RO_NASID_OFFSET(t0)
94 	lh	t2, KV_RW_NASID_OFFSET(t0)
95 	MAPPED_KERNEL_SETUP_TLB
96 
97 	/*
98 	 * We might not get launched at the address the kernel is linked to,
99 	 * so we jump there.
100 	 */
101 	PTR_LA	t0, 0f
102 	jr	t0
103 0:
104 	.endm
105 
106 #endif /* __ASM_MACH_IP27_KERNEL_ENTRY_H */
107