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