diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-alpha/fpu.h |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'include/asm-alpha/fpu.h')
-rw-r--r-- | include/asm-alpha/fpu.h | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/include/asm-alpha/fpu.h b/include/asm-alpha/fpu.h new file mode 100644 index 000000000000..c203fc2fa5cd --- /dev/null +++ b/include/asm-alpha/fpu.h | |||
@@ -0,0 +1,193 @@ | |||
1 | #ifndef __ASM_ALPHA_FPU_H | ||
2 | #define __ASM_ALPHA_FPU_H | ||
3 | |||
4 | /* | ||
5 | * Alpha floating-point control register defines: | ||
6 | */ | ||
7 | #define FPCR_DNOD (1UL<<47) /* denorm INV trap disable */ | ||
8 | #define FPCR_DNZ (1UL<<48) /* denorms to zero */ | ||
9 | #define FPCR_INVD (1UL<<49) /* invalid op disable (opt.) */ | ||
10 | #define FPCR_DZED (1UL<<50) /* division by zero disable (opt.) */ | ||
11 | #define FPCR_OVFD (1UL<<51) /* overflow disable (optional) */ | ||
12 | #define FPCR_INV (1UL<<52) /* invalid operation */ | ||
13 | #define FPCR_DZE (1UL<<53) /* division by zero */ | ||
14 | #define FPCR_OVF (1UL<<54) /* overflow */ | ||
15 | #define FPCR_UNF (1UL<<55) /* underflow */ | ||
16 | #define FPCR_INE (1UL<<56) /* inexact */ | ||
17 | #define FPCR_IOV (1UL<<57) /* integer overflow */ | ||
18 | #define FPCR_UNDZ (1UL<<60) /* underflow to zero (opt.) */ | ||
19 | #define FPCR_UNFD (1UL<<61) /* underflow disable (opt.) */ | ||
20 | #define FPCR_INED (1UL<<62) /* inexact disable (opt.) */ | ||
21 | #define FPCR_SUM (1UL<<63) /* summary bit */ | ||
22 | |||
23 | #define FPCR_DYN_SHIFT 58 /* first dynamic rounding mode bit */ | ||
24 | #define FPCR_DYN_CHOPPED (0x0UL << FPCR_DYN_SHIFT) /* towards 0 */ | ||
25 | #define FPCR_DYN_MINUS (0x1UL << FPCR_DYN_SHIFT) /* towards -INF */ | ||
26 | #define FPCR_DYN_NORMAL (0x2UL << FPCR_DYN_SHIFT) /* towards nearest */ | ||
27 | #define FPCR_DYN_PLUS (0x3UL << FPCR_DYN_SHIFT) /* towards +INF */ | ||
28 | #define FPCR_DYN_MASK (0x3UL << FPCR_DYN_SHIFT) | ||
29 | |||
30 | #define FPCR_MASK 0xffff800000000000L | ||
31 | |||
32 | /* | ||
33 | * IEEE trap enables are implemented in software. These per-thread | ||
34 | * bits are stored in the "ieee_state" field of "struct thread_info". | ||
35 | * Thus, the bits are defined so as not to conflict with the | ||
36 | * floating-point enable bit (which is architected). On top of that, | ||
37 | * we want to make these bits compatible with OSF/1 so | ||
38 | * ieee_set_fp_control() etc. can be implemented easily and | ||
39 | * compatibly. The corresponding definitions are in | ||
40 | * /usr/include/machine/fpu.h under OSF/1. | ||
41 | */ | ||
42 | #define IEEE_TRAP_ENABLE_INV (1UL<<1) /* invalid op */ | ||
43 | #define IEEE_TRAP_ENABLE_DZE (1UL<<2) /* division by zero */ | ||
44 | #define IEEE_TRAP_ENABLE_OVF (1UL<<3) /* overflow */ | ||
45 | #define IEEE_TRAP_ENABLE_UNF (1UL<<4) /* underflow */ | ||
46 | #define IEEE_TRAP_ENABLE_INE (1UL<<5) /* inexact */ | ||
47 | #define IEEE_TRAP_ENABLE_DNO (1UL<<6) /* denorm */ | ||
48 | #define IEEE_TRAP_ENABLE_MASK (IEEE_TRAP_ENABLE_INV | IEEE_TRAP_ENABLE_DZE |\ | ||
49 | IEEE_TRAP_ENABLE_OVF | IEEE_TRAP_ENABLE_UNF |\ | ||
50 | IEEE_TRAP_ENABLE_INE | IEEE_TRAP_ENABLE_DNO) | ||
51 | |||
52 | /* Denorm and Underflow flushing */ | ||
53 | #define IEEE_MAP_DMZ (1UL<<12) /* Map denorm inputs to zero */ | ||
54 | #define IEEE_MAP_UMZ (1UL<<13) /* Map underflowed outputs to zero */ | ||
55 | |||
56 | #define IEEE_MAP_MASK (IEEE_MAP_DMZ | IEEE_MAP_UMZ) | ||
57 | |||
58 | /* status bits coming from fpcr: */ | ||
59 | #define IEEE_STATUS_INV (1UL<<17) | ||
60 | #define IEEE_STATUS_DZE (1UL<<18) | ||
61 | #define IEEE_STATUS_OVF (1UL<<19) | ||
62 | #define IEEE_STATUS_UNF (1UL<<20) | ||
63 | #define IEEE_STATUS_INE (1UL<<21) | ||
64 | #define IEEE_STATUS_DNO (1UL<<22) | ||
65 | |||
66 | #define IEEE_STATUS_MASK (IEEE_STATUS_INV | IEEE_STATUS_DZE | \ | ||
67 | IEEE_STATUS_OVF | IEEE_STATUS_UNF | \ | ||
68 | IEEE_STATUS_INE | IEEE_STATUS_DNO) | ||
69 | |||
70 | #define IEEE_SW_MASK (IEEE_TRAP_ENABLE_MASK | \ | ||
71 | IEEE_STATUS_MASK | IEEE_MAP_MASK) | ||
72 | |||
73 | #define IEEE_CURRENT_RM_SHIFT 32 | ||
74 | #define IEEE_CURRENT_RM_MASK (3UL<<IEEE_CURRENT_RM_SHIFT) | ||
75 | |||
76 | #define IEEE_STATUS_TO_EXCSUM_SHIFT 16 | ||
77 | |||
78 | #define IEEE_INHERIT (1UL<<63) /* inherit on thread create? */ | ||
79 | |||
80 | /* | ||
81 | * Convert the software IEEE trap enable and status bits into the | ||
82 | * hardware fpcr format. | ||
83 | * | ||
84 | * Digital Unix engineers receive my thanks for not defining the | ||
85 | * software bits identical to the hardware bits. The chip designers | ||
86 | * receive my thanks for making all the not-implemented fpcr bits | ||
87 | * RAZ forcing us to use system calls to read/write this value. | ||
88 | */ | ||
89 | |||
90 | static inline unsigned long | ||
91 | ieee_swcr_to_fpcr(unsigned long sw) | ||
92 | { | ||
93 | unsigned long fp; | ||
94 | fp = (sw & IEEE_STATUS_MASK) << 35; | ||
95 | fp |= (sw & IEEE_MAP_DMZ) << 36; | ||
96 | fp |= (sw & IEEE_STATUS_MASK ? FPCR_SUM : 0); | ||
97 | fp |= (~sw & (IEEE_TRAP_ENABLE_INV | ||
98 | | IEEE_TRAP_ENABLE_DZE | ||
99 | | IEEE_TRAP_ENABLE_OVF)) << 48; | ||
100 | fp |= (~sw & (IEEE_TRAP_ENABLE_UNF | IEEE_TRAP_ENABLE_INE)) << 57; | ||
101 | fp |= (sw & IEEE_MAP_UMZ ? FPCR_UNDZ | FPCR_UNFD : 0); | ||
102 | fp |= (~sw & IEEE_TRAP_ENABLE_DNO) << 41; | ||
103 | return fp; | ||
104 | } | ||
105 | |||
106 | static inline unsigned long | ||
107 | ieee_fpcr_to_swcr(unsigned long fp) | ||
108 | { | ||
109 | unsigned long sw; | ||
110 | sw = (fp >> 35) & IEEE_STATUS_MASK; | ||
111 | sw |= (fp >> 36) & IEEE_MAP_DMZ; | ||
112 | sw |= (~fp >> 48) & (IEEE_TRAP_ENABLE_INV | ||
113 | | IEEE_TRAP_ENABLE_DZE | ||
114 | | IEEE_TRAP_ENABLE_OVF); | ||
115 | sw |= (~fp >> 57) & (IEEE_TRAP_ENABLE_UNF | IEEE_TRAP_ENABLE_INE); | ||
116 | sw |= (fp >> 47) & IEEE_MAP_UMZ; | ||
117 | sw |= (~fp >> 41) & IEEE_TRAP_ENABLE_DNO; | ||
118 | return sw; | ||
119 | } | ||
120 | |||
121 | #ifdef __KERNEL__ | ||
122 | |||
123 | /* The following two functions don't need trapb/excb instructions | ||
124 | around the mf_fpcr/mt_fpcr instructions because (a) the kernel | ||
125 | never generates arithmetic faults and (b) call_pal instructions | ||
126 | are implied trap barriers. */ | ||
127 | |||
128 | static inline unsigned long | ||
129 | rdfpcr(void) | ||
130 | { | ||
131 | unsigned long tmp, ret; | ||
132 | |||
133 | #if defined(__alpha_cix__) || defined(__alpha_fix__) | ||
134 | __asm__ __volatile__ ( | ||
135 | "ftoit $f0,%0\n\t" | ||
136 | "mf_fpcr $f0\n\t" | ||
137 | "ftoit $f0,%1\n\t" | ||
138 | "itoft %0,$f0" | ||
139 | : "=r"(tmp), "=r"(ret)); | ||
140 | #else | ||
141 | __asm__ __volatile__ ( | ||
142 | "stt $f0,%0\n\t" | ||
143 | "mf_fpcr $f0\n\t" | ||
144 | "stt $f0,%1\n\t" | ||
145 | "ldt $f0,%0" | ||
146 | : "=m"(tmp), "=m"(ret)); | ||
147 | #endif | ||
148 | |||
149 | return ret; | ||
150 | } | ||
151 | |||
152 | static inline void | ||
153 | wrfpcr(unsigned long val) | ||
154 | { | ||
155 | unsigned long tmp; | ||
156 | |||
157 | #if defined(__alpha_cix__) || defined(__alpha_fix__) | ||
158 | __asm__ __volatile__ ( | ||
159 | "ftoit $f0,%0\n\t" | ||
160 | "itoft %1,$f0\n\t" | ||
161 | "mt_fpcr $f0\n\t" | ||
162 | "itoft %0,$f0" | ||
163 | : "=&r"(tmp) : "r"(val)); | ||
164 | #else | ||
165 | __asm__ __volatile__ ( | ||
166 | "stt $f0,%0\n\t" | ||
167 | "ldt $f0,%1\n\t" | ||
168 | "mt_fpcr $f0\n\t" | ||
169 | "ldt $f0,%0" | ||
170 | : "=m"(tmp) : "m"(val)); | ||
171 | #endif | ||
172 | } | ||
173 | |||
174 | static inline unsigned long | ||
175 | swcr_update_status(unsigned long swcr, unsigned long fpcr) | ||
176 | { | ||
177 | /* EV6 implements most of the bits in hardware. Collect | ||
178 | the acrued exception bits from the real fpcr. */ | ||
179 | if (implver() == IMPLVER_EV6) { | ||
180 | swcr &= ~IEEE_STATUS_MASK; | ||
181 | swcr |= (fpcr >> 35) & IEEE_STATUS_MASK; | ||
182 | } | ||
183 | return swcr; | ||
184 | } | ||
185 | |||
186 | extern unsigned long alpha_read_fp_reg (unsigned long reg); | ||
187 | extern void alpha_write_fp_reg (unsigned long reg, unsigned long val); | ||
188 | extern unsigned long alpha_read_fp_reg_s (unsigned long reg); | ||
189 | extern void alpha_write_fp_reg_s (unsigned long reg, unsigned long val); | ||
190 | |||
191 | #endif /* __KERNEL__ */ | ||
192 | |||
193 | #endif /* __ASM_ALPHA_FPU_H */ | ||