1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * include/asm-sh/processor.h
4 *
5 * Copyright (C) 1999, 2000 Niibe Yutaka
6 * Copyright (C) 2002, 2003 Paul Mundt
7 */
8
9 #ifndef __ASM_SH_PROCESSOR_32_H
10 #define __ASM_SH_PROCESSOR_32_H
11 #ifdef __KERNEL__
12
13 #include <linux/compiler.h>
14 #include <linux/linkage.h>
15 #include <asm/page.h>
16 #include <asm/types.h>
17 #include <asm/hw_breakpoint.h>
18
19 /* Core Processor Version Register */
20 #define CCN_PVR 0xff000030
21 #define CCN_CVR 0xff000040
22 #define CCN_PRR 0xff000044
23
24 /*
25 * User space process size: 2GB.
26 *
27 * Since SH7709 and SH7750 have "area 7", we can't use 0x7c000000--0x7fffffff
28 */
29 #define TASK_SIZE 0x7c000000UL
30
31 #define STACK_TOP TASK_SIZE
32 #define STACK_TOP_MAX STACK_TOP
33
34 /* This decides where the kernel will search for a free chunk of vm
35 * space during mmap's.
36 */
37 #define TASK_UNMAPPED_BASE PAGE_ALIGN(TASK_SIZE / 3)
38
39 /*
40 * Bit of SR register
41 *
42 * FD-bit:
43 * When it's set, it means the processor doesn't have right to use FPU,
44 * and it results exception when the floating operation is executed.
45 *
46 * IMASK-bit:
47 * Interrupt level mask
48 */
49 #define SR_DSP 0x00001000
50 #define SR_IMASK 0x000000f0
51 #define SR_FD 0x00008000
52 #define SR_MD 0x40000000
53
54 /*
55 * DSP structure and data
56 */
57 struct sh_dsp_struct {
58 unsigned long dsp_regs[14];
59 long status;
60 };
61
62 /*
63 * FPU structure and data
64 */
65
66 struct sh_fpu_hard_struct {
67 unsigned long fp_regs[16];
68 unsigned long xfp_regs[16];
69 unsigned long fpscr;
70 unsigned long fpul;
71
72 long status; /* software status information */
73 };
74
75 /* Dummy fpu emulator */
76 struct sh_fpu_soft_struct {
77 unsigned long fp_regs[16];
78 unsigned long xfp_regs[16];
79 unsigned long fpscr;
80 unsigned long fpul;
81
82 unsigned char lookahead;
83 unsigned long entry_pc;
84 };
85
86 union thread_xstate {
87 struct sh_fpu_hard_struct hardfpu;
88 struct sh_fpu_soft_struct softfpu;
89 };
90
91 struct thread_struct {
92 /* Saved registers when thread is descheduled */
93 unsigned long sp;
94 unsigned long pc;
95
96 /* Various thread flags, see SH_THREAD_xxx */
97 unsigned long flags;
98
99 /* Save middle states of ptrace breakpoints */
100 struct perf_event *ptrace_bps[HBP_NUM];
101
102 #ifdef CONFIG_SH_DSP
103 /* Dsp status information */
104 struct sh_dsp_struct dsp_status;
105 #endif
106
107 /* Extended processor state */
108 union thread_xstate *xstate;
109
110 /*
111 * fpu_counter contains the number of consecutive context switches
112 * that the FPU is used. If this is over a threshold, the lazy fpu
113 * saving becomes unlazy to save the trap. This is an unsigned char
114 * so that after 256 times the counter wraps and the behavior turns
115 * lazy again; this to deal with bursty apps that only use FPU for
116 * a short time
117 */
118 unsigned char fpu_counter;
119 };
120
121 #define INIT_THREAD { \
122 .sp = sizeof(init_stack) + (long) &init_stack, \
123 .flags = 0, \
124 }
125
126 /* Forward declaration, a strange C thing */
127 struct task_struct;
128
129 extern void start_thread(struct pt_regs *regs, unsigned long new_pc, unsigned long new_sp);
130
131 /* Free all resources held by a thread. */
132 extern void release_thread(struct task_struct *);
133
134 /*
135 * FPU lazy state save handling.
136 */
137
disable_fpu(void)138 static __inline__ void disable_fpu(void)
139 {
140 unsigned long __dummy;
141
142 /* Set FD flag in SR */
143 __asm__ __volatile__("stc sr, %0\n\t"
144 "or %1, %0\n\t"
145 "ldc %0, sr"
146 : "=&r" (__dummy)
147 : "r" (SR_FD));
148 }
149
enable_fpu(void)150 static __inline__ void enable_fpu(void)
151 {
152 unsigned long __dummy;
153
154 /* Clear out FD flag in SR */
155 __asm__ __volatile__("stc sr, %0\n\t"
156 "and %1, %0\n\t"
157 "ldc %0, sr"
158 : "=&r" (__dummy)
159 : "r" (~SR_FD));
160 }
161
162 /* Double presision, NANS as NANS, rounding to nearest, no exceptions */
163 #define FPSCR_INIT 0x00080000
164
165 #define FPSCR_CAUSE_MASK 0x0001f000 /* Cause bits */
166 #define FPSCR_FLAG_MASK 0x0000007c /* Flag bits */
167
168 /*
169 * Return saved PC of a blocked thread.
170 */
171 #define thread_saved_pc(tsk) (tsk->thread.pc)
172
173 void show_trace(struct task_struct *tsk, unsigned long *sp,
174 struct pt_regs *regs);
175
176 #ifdef CONFIG_DUMP_CODE
177 void show_code(struct pt_regs *regs);
178 #else
show_code(struct pt_regs * regs)179 static inline void show_code(struct pt_regs *regs)
180 {
181 }
182 #endif
183
184 extern unsigned long get_wchan(struct task_struct *p);
185
186 #define KSTK_EIP(tsk) (task_pt_regs(tsk)->pc)
187 #define KSTK_ESP(tsk) (task_pt_regs(tsk)->regs[15])
188
189 #if defined(CONFIG_CPU_SH2A) || defined(CONFIG_CPU_SH4)
190
191 #define PREFETCH_STRIDE L1_CACHE_BYTES
192 #define ARCH_HAS_PREFETCH
193 #define ARCH_HAS_PREFETCHW
194
prefetch(const void * x)195 static inline void prefetch(const void *x)
196 {
197 __builtin_prefetch(x, 0, 3);
198 }
199
prefetchw(const void * x)200 static inline void prefetchw(const void *x)
201 {
202 __builtin_prefetch(x, 1, 3);
203 }
204 #endif
205
206 #endif /* __KERNEL__ */
207 #endif /* __ASM_SH_PROCESSOR_32_H */
208
