xref: /linux/arch/powerpc/kernel/ptrace/ptrace-fpu.c (revision 908fc4c2)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 
3 #include <linux/regset.h>
4 
5 #include <asm/switch_to.h>
6 
7 #include "ptrace-decl.h"
8 
9 int ptrace_get_fpr(struct task_struct *child, int index, unsigned long *data)
10 {
11 #ifdef CONFIG_PPC_FPU_REGS
12 	unsigned int fpidx = index - PT_FPR0;
13 #endif
14 
15 	if (index > PT_FPSCR)
16 		return -EIO;
17 
18 #ifdef CONFIG_PPC_FPU_REGS
19 	flush_fp_to_thread(child);
20 	if (fpidx < (PT_FPSCR - PT_FPR0)) {
21 		if (IS_ENABLED(CONFIG_PPC32))
22 			// On 32-bit the index we are passed refers to 32-bit words
23 			*data = ((u32 *)child->thread.fp_state.fpr)[fpidx];
24 		else
25 			memcpy(data, &child->thread.TS_FPR(fpidx), sizeof(long));
26 	} else
27 		*data = child->thread.fp_state.fpscr;
28 #else
29 	*data = 0;
30 #endif
31 
32 	return 0;
33 }
34 
35 int ptrace_put_fpr(struct task_struct *child, int index, unsigned long data)
36 {
37 #ifdef CONFIG_PPC_FPU_REGS
38 	unsigned int fpidx = index - PT_FPR0;
39 #endif
40 
41 	if (index > PT_FPSCR)
42 		return -EIO;
43 
44 #ifdef CONFIG_PPC_FPU_REGS
45 	flush_fp_to_thread(child);
46 	if (fpidx < (PT_FPSCR - PT_FPR0)) {
47 		if (IS_ENABLED(CONFIG_PPC32))
48 			// On 32-bit the index we are passed refers to 32-bit words
49 			((u32 *)child->thread.fp_state.fpr)[fpidx] = data;
50 		else
51 			memcpy(&child->thread.TS_FPR(fpidx), &data, sizeof(long));
52 	} else
53 		child->thread.fp_state.fpscr = data;
54 #endif
55 
56 	return 0;
57 }
58 
59