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Documentation: Delete dead OSS-related kernel parameter.
[net-next-2.6.git] / arch / x86 / kernel / cpu / cyrix.c
CommitLineData
1da177e4
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1#include <linux/init.h>
2#include <linux/bitops.h>
3#include <linux/delay.h>
4#include <linux/pci.h>
5#include <asm/dma.h>
6#include <asm/io.h>
f25f64ed 7#include <asm/processor-cyrix.h>
1da177e4 8#include <asm/timer.h>
120fad72 9#include <asm/pci-direct.h>
e8edc6e0 10#include <asm/tsc.h>
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11
12#include "cpu.h"
13
14/*
15 * Read NSC/Cyrix DEVID registers (DIR) to get more detailed info. about the CPU
16 */
5f0f1c16 17static void __cpuinit do_cyrix_devid(unsigned char *dir0, unsigned char *dir1)
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18{
19 unsigned char ccr2, ccr3;
20 unsigned long flags;
21
22 /* we test for DEVID by checking whether CCR3 is writable */
23 local_irq_save(flags);
24 ccr3 = getCx86(CX86_CCR3);
25 setCx86(CX86_CCR3, ccr3 ^ 0x80);
26 getCx86(0xc0); /* dummy to change bus */
27
28 if (getCx86(CX86_CCR3) == ccr3) { /* no DEVID regs. */
29 ccr2 = getCx86(CX86_CCR2);
30 setCx86(CX86_CCR2, ccr2 ^ 0x04);
31 getCx86(0xc0); /* dummy */
32
33 if (getCx86(CX86_CCR2) == ccr2) /* old Cx486SLC/DLC */
34 *dir0 = 0xfd;
35 else { /* Cx486S A step */
36 setCx86(CX86_CCR2, ccr2);
37 *dir0 = 0xfe;
38 }
39 }
40 else {
41 setCx86(CX86_CCR3, ccr3); /* restore CCR3 */
42
43 /* read DIR0 and DIR1 CPU registers */
44 *dir0 = getCx86(CX86_DIR0);
45 *dir1 = getCx86(CX86_DIR1);
46 }
47 local_irq_restore(flags);
48}
49
50/*
51 * Cx86_dir0_msb is a HACK needed by check_cx686_cpuid/slop in bugs.h in
52 * order to identify the Cyrix CPU model after we're out of setup.c
53 *
54 * Actually since bugs.h doesn't even reference this perhaps someone should
55 * fix the documentation ???
56 */
b4af3f7c 57static unsigned char Cx86_dir0_msb __cpuinitdata = 0;
1da177e4 58
b4af3f7c 59static char Cx86_model[][9] __cpuinitdata = {
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60 "Cx486", "Cx486", "5x86 ", "6x86", "MediaGX ", "6x86MX ",
61 "M II ", "Unknown"
62};
b4af3f7c 63static char Cx486_name[][5] __cpuinitdata = {
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64 "SLC", "DLC", "SLC2", "DLC2", "SRx", "DRx",
65 "SRx2", "DRx2"
66};
b4af3f7c 67static char Cx486S_name[][4] __cpuinitdata = {
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68 "S", "S2", "Se", "S2e"
69};
b4af3f7c 70static char Cx486D_name[][4] __cpuinitdata = {
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71 "DX", "DX2", "?", "?", "?", "DX4"
72};
b4af3f7c
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73static char Cx86_cb[] __cpuinitdata = "?.5x Core/Bus Clock";
74static char cyrix_model_mult1[] __cpuinitdata = "12??43";
75static char cyrix_model_mult2[] __cpuinitdata = "12233445";
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76
77/*
78 * Reset the slow-loop (SLOP) bit on the 686(L) which is set by some old
79 * BIOSes for compatibility with DOS games. This makes the udelay loop
80 * work correctly, and improves performance.
81 *
82 * FIXME: our newer udelay uses the tsc. We don't need to frob with SLOP
83 */
84
85extern void calibrate_delay(void) __init;
86
b4af3f7c 87static void __cpuinit check_cx686_slop(struct cpuinfo_x86 *c)
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88{
89 unsigned long flags;
90
91 if (Cx86_dir0_msb == 3) {
92 unsigned char ccr3, ccr5;
93
94 local_irq_save(flags);
95 ccr3 = getCx86(CX86_CCR3);
96 setCx86(CX86_CCR3, (ccr3 & 0x0f) | 0x10); /* enable MAPEN */
97 ccr5 = getCx86(CX86_CCR5);
98 if (ccr5 & 2)
99 setCx86(CX86_CCR5, ccr5 & 0xfd); /* reset SLOP */
100 setCx86(CX86_CCR3, ccr3); /* disable MAPEN */
101 local_irq_restore(flags);
102
103 if (ccr5 & 2) { /* possible wrong calibration done */
104 printk(KERN_INFO "Recalibrating delay loop with SLOP bit reset\n");
105 calibrate_delay();
106 c->loops_per_jiffy = loops_per_jiffy;
107 }
108 }
109}
110
111
b4af3f7c 112static void __cpuinit set_cx86_reorder(void)
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113{
114 u8 ccr3;
115
116 printk(KERN_INFO "Enable Memory access reorder on Cyrix/NSC processor.\n");
117 ccr3 = getCx86(CX86_CCR3);
118