1 | /* |
2 | * Setup the right wbflush routine for the different DECstations. |
3 | * |
4 | * Created with information from: |
5 | * DECstation 3100 Desktop Workstation Functional Specification |
6 | * DECstation 5000/200 KN02 System Module Functional Specification |
7 | * mipsel-linux-objdump --disassemble vmunix | grep "wbflush" :-) |
8 | * |
9 | * This file is subject to the terms and conditions of the GNU General Public |
10 | * License. See the file "COPYING" in the main directory of this archive |
11 | * for more details. |
12 | * |
13 | * Copyright (C) 1998 Harald Koerfgen |
14 | * Copyright (C) 2002 Maciej W. Rozycki |
15 | */ |
16 | |
17 | #include <linux/export.h> |
18 | #include <linux/init.h> |
19 | |
20 | #include <asm/bootinfo.h> |
21 | #include <asm/wbflush.h> |
22 | #include <asm/barrier.h> |
23 | |
24 | static void wbflush_kn01(void); |
25 | static void wbflush_kn210(void); |
26 | static void wbflush_mips(void); |
27 | |
28 | void (*__wbflush) (void); |
29 | |
30 | void __init wbflush_setup(void) |
31 | { |
32 | switch (mips_machtype) { |
33 | case MACH_DS23100: |
34 | case MACH_DS5000_200: /* DS5000 3max */ |
35 | __wbflush = wbflush_kn01; |
36 | break; |
37 | case MACH_DS5100: /* DS5100 MIPSMATE */ |
38 | __wbflush = wbflush_kn210; |
39 | break; |
40 | case MACH_DS5000_1XX: /* DS5000/100 3min */ |
41 | case MACH_DS5000_XX: /* Personal DS5000/2x */ |
42 | case MACH_DS5000_2X0: /* DS5000/240 3max+ */ |
43 | case MACH_DS5900: /* DS5900 bigmax */ |
44 | default: |
45 | __wbflush = wbflush_mips; |
46 | break; |
47 | } |
48 | } |
49 | |
50 | /* |
51 | * For the DS3100 and DS5000/200 the R2020/R3220 writeback buffer functions |
52 | * as part of Coprocessor 0. |
53 | */ |
54 | static void wbflush_kn01(void) |
55 | { |
56 | asm(".set\tpush\n\t" |
57 | ".set\tnoreorder\n\t" |
58 | "1:\tbc0f\t1b\n\t" |
59 | "nop\n\t" |
60 | ".set\tpop" ); |
61 | } |
62 | |
63 | /* |
64 | * For the DS5100 the writeback buffer seems to be a part of Coprocessor 3. |
65 | * But CP3 has to enabled first. |
66 | */ |
67 | static void wbflush_kn210(void) |
68 | { |
69 | asm(".set\tpush\n\t" |
70 | ".set\tnoreorder\n\t" |
71 | "mfc0\t$2,$12\n\t" |
72 | "lui\t$3,0x8000\n\t" |
73 | "or\t$3,$2,$3\n\t" |
74 | "mtc0\t$3,$12\n\t" |
75 | "nop\n" |
76 | "1:\tbc3f\t1b\n\t" |
77 | "nop\n\t" |
78 | "mtc0\t$2,$12\n\t" |
79 | "nop\n\t" |
80 | ".set\tpop" |
81 | : : : "$2" , "$3" ); |
82 | } |
83 | |
84 | /* |
85 | * I/O ASIC systems use a standard writeback buffer that gets flushed |
86 | * upon an uncached read. |
87 | */ |
88 | static void wbflush_mips(void) |
89 | { |
90 | __fast_iob(); |
91 | } |
92 | EXPORT_SYMBOL(__wbflush); |
93 | |