1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __ASM_ALPHA_FPU_H
3 #define __ASM_ALPHA_FPU_H
4
5 #include <asm/special_insns.h>
6 #include <uapi/asm/fpu.h>
7
8 /* The following two functions don't need trapb/excb instructions
9 around the mf_fpcr/mt_fpcr instructions because (a) the kernel
10 never generates arithmetic faults and (b) call_pal instructions
11 are implied trap barriers. */
12
13 static inline unsigned long
rdfpcr(void)14 rdfpcr(void)
15 {
16 unsigned long tmp, ret;
17
18 #if defined(CONFIG_ALPHA_EV6) || defined(CONFIG_ALPHA_EV67)
19 __asm__ __volatile__ (
20 "ftoit $f0,%0\n\t"
21 "mf_fpcr $f0\n\t"
22 "ftoit $f0,%1\n\t"
23 "itoft %0,$f0"
24 : "=r"(tmp), "=r"(ret));
25 #else
26 __asm__ __volatile__ (
27 "stt $f0,%0\n\t"
28 "mf_fpcr $f0\n\t"
29 "stt $f0,%1\n\t"
30 "ldt $f0,%0"
31 : "=m"(tmp), "=m"(ret));
32 #endif
33
34 return ret;
35 }
36
37 static inline void
wrfpcr(unsigned long val)38 wrfpcr(unsigned long val)
39 {
40 unsigned long tmp;
41
42 #if defined(CONFIG_ALPHA_EV6) || defined(CONFIG_ALPHA_EV67)
43 __asm__ __volatile__ (
44 "ftoit $f0,%0\n\t"
45 "itoft %1,$f0\n\t"
46 "mt_fpcr $f0\n\t"
47 "itoft %0,$f0"
48 : "=&r"(tmp) : "r"(val));
49 #else
50 __asm__ __volatile__ (
51 "stt $f0,%0\n\t"
52 "ldt $f0,%1\n\t"
53 "mt_fpcr $f0\n\t"
54 "ldt $f0,%0"
55 : "=m"(tmp) : "m"(val));
56 #endif
57 }
58
59 static inline unsigned long
swcr_update_status(unsigned long swcr,unsigned long fpcr)60 swcr_update_status(unsigned long swcr, unsigned long fpcr)
61 {
62 /* EV6 implements most of the bits in hardware. Collect
63 the acrued exception bits from the real fpcr. */
64 if (implver() == IMPLVER_EV6) {
65 swcr &= ~IEEE_STATUS_MASK;
66 swcr |= (fpcr >> 35) & IEEE_STATUS_MASK;
67 }
68 return swcr;
69 }
70
71 extern unsigned long alpha_read_fp_reg (unsigned long reg);
72 extern void alpha_write_fp_reg (unsigned long reg, unsigned long val);
73 extern unsigned long alpha_read_fp_reg_s (unsigned long reg);
74 extern void alpha_write_fp_reg_s (unsigned long reg, unsigned long val);
75
76 #endif /* __ASM_ALPHA_FPU_H */
77