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1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * FPU support code, moved here from head.S so that it can be used
4 * by chips which use other head-whatever.S files.
5 *
6 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
7 * Copyright (C) 1996 Cort Dougan <cort@cs.nmt.edu>
8 * Copyright (C) 1996 Paul Mackerras.
9 * Copyright (C) 1997 Dan Malek (dmalek@jlc.net).
10 */
11
12#include <asm/reg.h>
13#include <asm/page.h>
14#include <asm/mmu.h>
15#include <asm/cputable.h>
16#include <asm/cache.h>
17#include <asm/thread_info.h>
18#include <asm/ppc_asm.h>
19#include <asm/asm-offsets.h>
20#include <asm/ptrace.h>
21#include <asm/export.h>
22#include <asm/asm-compat.h>
23#include <asm/feature-fixups.h>
24
25#ifdef CONFIG_VSX
26#define __REST_32FPVSRS(n,c,base) \
27BEGIN_FTR_SECTION \
28 b 2f; \
29END_FTR_SECTION_IFSET(CPU_FTR_VSX); \
30 REST_32FPRS(n,base); \
31 b 3f; \
322: REST_32VSRS(n,c,base); \
333:
34
35#define __SAVE_32FPVSRS(n,c,base) \
36BEGIN_FTR_SECTION \
37 b 2f; \
38END_FTR_SECTION_IFSET(CPU_FTR_VSX); \
39 SAVE_32FPRS(n,base); \
40 b 3f; \
412: SAVE_32VSRS(n,c,base); \
423:
43#else
44#define __REST_32FPVSRS(n,b,base) REST_32FPRS(n, base)
45#define __SAVE_32FPVSRS(n,b,base) SAVE_32FPRS(n, base)
46#endif
47#define REST_32FPVSRS(n,c,base) __REST_32FPVSRS(n,__REG_##c,__REG_##base)
48#define SAVE_32FPVSRS(n,c,base) __SAVE_32FPVSRS(n,__REG_##c,__REG_##base)
49
50/*
51 * Load state from memory into FP registers including FPSCR.
52 * Assumes the caller has enabled FP in the MSR.
53 */
54_GLOBAL(load_fp_state)
55 lfd fr0,FPSTATE_FPSCR(r3)
56 MTFSF_L(fr0)
57 REST_32FPVSRS(0, R4, R3)
58 blr
59EXPORT_SYMBOL(load_fp_state)
60_ASM_NOKPROBE_SYMBOL(load_fp_state); /* used by restore_math */
61
62/*
63 * Store FP state into memory, including FPSCR
64 * Assumes the caller has enabled FP in the MSR.
65 */
66_GLOBAL(store_fp_state)
67 SAVE_32FPVSRS(0, R4, R3)
68 mffs fr0
69 stfd fr0,FPSTATE_FPSCR(r3)
70 blr
71EXPORT_SYMBOL(store_fp_state)
72
73/*
74 * This task wants to use the FPU now.
75 * On UP, disable FP for the task which had the FPU previously,
76 * and save its floating-point registers in its thread_struct.
77 * Load up this task's FP registers from its thread_struct,
78 * enable the FPU for the current task and return to the task.
79 * Note that on 32-bit this can only use registers that will be
80 * restored by fast_exception_return, i.e. r3 - r6, r10 and r11.
81 */
82_GLOBAL(load_up_fpu)
83 mfmsr r5
84#ifdef CONFIG_PPC_BOOK3S_64
85 /* interrupt doesn't set MSR[RI] and HPT can fault on current access */
86 ori r5,r5,MSR_FP|MSR_RI
87#else
88 ori r5,r5,MSR_FP
89#endif
90#ifdef CONFIG_VSX
91BEGIN_FTR_SECTION
92 oris r5,r5,MSR_VSX@h
93END_FTR_SECTION_IFSET(CPU_FTR_VSX)
94#endif
95 MTMSRD(r5) /* enable use of fpu now */
96 isync
97 /* enable use of FP after return */
98#ifdef CONFIG_PPC32
99 addi r5,r2,THREAD
100 lwz r4,THREAD_FPEXC_MODE(r5)
101 ori r9,r9,MSR_FP /* enable FP for current */
102 or r9,r9,r4
103#else
104 ld r4,PACACURRENT(r13)
105 addi r5,r4,THREAD /* Get THREAD */
106 lwz r4,THREAD_FPEXC_MODE(r5)
107 ori r12,r12,MSR_FP
108 or r12,r12,r4
109 std r12,_MSR(r1)
110#ifdef CONFIG_PPC_BOOK3S_64
111 li r4,0
112 stb r4,PACASRR_VALID(r13)
113#endif
114#endif
115 li r4,1
116 stb r4,THREAD_LOAD_FP(r5)
117 addi r10,r5,THREAD_FPSTATE
118 lfd fr0,FPSTATE_FPSCR(r10)
119 MTFSF_L(fr0)
120 REST_32FPVSRS(0, R4, R10)
121 /* restore registers and return */
122 /* we haven't used ctr or xer or lr */
123 blr
124_ASM_NOKPROBE_SYMBOL(load_up_fpu)
125
126/*
127 * save_fpu(tsk)
128 * Save the floating-point registers in its thread_struct.
129 * Enables the FPU for use in the kernel on return.
130 */
131_GLOBAL(save_fpu)
132 addi r3,r3,THREAD /* want THREAD of task */
133 PPC_LL r6,THREAD_FPSAVEAREA(r3)
134 PPC_LL r5,PT_REGS(r3)
135 PPC_LCMPI 0,r6,0
136 bne 2f
137 addi r6,r3,THREAD_FPSTATE
1382: SAVE_32FPVSRS(0, R4, R6)
139 mffs fr0
140 stfd fr0,FPSTATE_FPSCR(r6)
141 blr
1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * FPU support code, moved here from head.S so that it can be used
4 * by chips which use other head-whatever.S files.
5 *
6 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
7 * Copyright (C) 1996 Cort Dougan <cort@cs.nmt.edu>
8 * Copyright (C) 1996 Paul Mackerras.
9 * Copyright (C) 1997 Dan Malek (dmalek@jlc.net).
10 */
11
12#include <asm/reg.h>
13#include <asm/page.h>
14#include <asm/mmu.h>
15#include <asm/pgtable.h>
16#include <asm/cputable.h>
17#include <asm/cache.h>
18#include <asm/thread_info.h>
19#include <asm/ppc_asm.h>
20#include <asm/asm-offsets.h>
21#include <asm/ptrace.h>
22#include <asm/export.h>
23#include <asm/asm-compat.h>
24#include <asm/feature-fixups.h>
25
26#ifdef CONFIG_VSX
27#define __REST_32FPVSRS(n,c,base) \
28BEGIN_FTR_SECTION \
29 b 2f; \
30END_FTR_SECTION_IFSET(CPU_FTR_VSX); \
31 REST_32FPRS(n,base); \
32 b 3f; \
332: REST_32VSRS(n,c,base); \
343:
35
36#define __SAVE_32FPVSRS(n,c,base) \
37BEGIN_FTR_SECTION \
38 b 2f; \
39END_FTR_SECTION_IFSET(CPU_FTR_VSX); \
40 SAVE_32FPRS(n,base); \
41 b 3f; \
422: SAVE_32VSRS(n,c,base); \
433:
44#else
45#define __REST_32FPVSRS(n,b,base) REST_32FPRS(n, base)
46#define __SAVE_32FPVSRS(n,b,base) SAVE_32FPRS(n, base)
47#endif
48#define REST_32FPVSRS(n,c,base) __REST_32FPVSRS(n,__REG_##c,__REG_##base)
49#define SAVE_32FPVSRS(n,c,base) __SAVE_32FPVSRS(n,__REG_##c,__REG_##base)
50
51/*
52 * Load state from memory into FP registers including FPSCR.
53 * Assumes the caller has enabled FP in the MSR.
54 */
55_GLOBAL(load_fp_state)
56 lfd fr0,FPSTATE_FPSCR(r3)
57 MTFSF_L(fr0)
58 REST_32FPVSRS(0, R4, R3)
59 blr
60EXPORT_SYMBOL(load_fp_state)
61_ASM_NOKPROBE_SYMBOL(load_fp_state); /* used by restore_math */
62
63/*
64 * Store FP state into memory, including FPSCR
65 * Assumes the caller has enabled FP in the MSR.
66 */
67_GLOBAL(store_fp_state)
68 SAVE_32FPVSRS(0, R4, R3)
69 mffs fr0
70 stfd fr0,FPSTATE_FPSCR(r3)
71 blr
72EXPORT_SYMBOL(store_fp_state)
73
74/*
75 * This task wants to use the FPU now.
76 * On UP, disable FP for the task which had the FPU previously,
77 * and save its floating-point registers in its thread_struct.
78 * Load up this task's FP registers from its thread_struct,
79 * enable the FPU for the current task and return to the task.
80 * Note that on 32-bit this can only use registers that will be
81 * restored by fast_exception_return, i.e. r3 - r6, r10 and r11.
82 */
83_GLOBAL(load_up_fpu)
84 mfmsr r5
85 ori r5,r5,MSR_FP
86#ifdef CONFIG_VSX
87BEGIN_FTR_SECTION
88 oris r5,r5,MSR_VSX@h
89END_FTR_SECTION_IFSET(CPU_FTR_VSX)
90#endif
91 SYNC
92 MTMSRD(r5) /* enable use of fpu now */
93 isync
94 /* enable use of FP after return */
95#ifdef CONFIG_PPC32
96 mfspr r5,SPRN_SPRG_THREAD /* current task's THREAD (phys) */
97 lwz r4,THREAD_FPEXC_MODE(r5)
98 ori r9,r9,MSR_FP /* enable FP for current */
99 or r9,r9,r4
100#else
101 ld r4,PACACURRENT(r13)
102 addi r5,r4,THREAD /* Get THREAD */
103 lwz r4,THREAD_FPEXC_MODE(r5)
104 ori r12,r12,MSR_FP
105 or r12,r12,r4
106 std r12,_MSR(r1)
107#endif
108 /* Don't care if r4 overflows, this is desired behaviour */
109 lbz r4,THREAD_LOAD_FP(r5)
110 addi r4,r4,1
111 stb r4,THREAD_LOAD_FP(r5)
112 addi r10,r5,THREAD_FPSTATE
113 lfd fr0,FPSTATE_FPSCR(r10)
114 MTFSF_L(fr0)
115 REST_32FPVSRS(0, R4, R10)
116 /* restore registers and return */
117 /* we haven't used ctr or xer or lr */
118 blr
119
120/*
121 * save_fpu(tsk)
122 * Save the floating-point registers in its thread_struct.
123 * Enables the FPU for use in the kernel on return.
124 */
125_GLOBAL(save_fpu)
126 addi r3,r3,THREAD /* want THREAD of task */
127 PPC_LL r6,THREAD_FPSAVEAREA(r3)
128 PPC_LL r5,PT_REGS(r3)
129 PPC_LCMPI 0,r6,0
130 bne 2f
131 addi r6,r3,THREAD_FPSTATE
1322: SAVE_32FPVSRS(0, R4, R6)
133 mffs fr0
134 stfd fr0,FPSTATE_FPSCR(r6)
135 blr
136
137/*
138 * These are used in the alignment trap handler when emulating
139 * single-precision loads and stores.
140 */
141
142_GLOBAL(cvt_fd)
143 lfs 0,0(r3)
144 stfd 0,0(r4)
145 blr
146
147_GLOBAL(cvt_df)
148 lfd 0,0(r3)
149 stfs 0,0(r4)
150 blr