1 /* SPDX-License-Identifier: GPL-2.0 */
2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
4 #ifndef __ASM_CSKY_PROCESSOR_H
5 #define __ASM_CSKY_PROCESSOR_H
8 * Default implementation of macro that returns current
9 * instruction pointer ("program counter").
11 #define current_text_addr() ({ __label__ _l; _l: &&_l; })
13 #include <linux/bitops.h>
14 #include <asm/segment.h>
15 #include <asm/ptrace.h>
16 #include <asm/current.h>
17 #include <asm/cache.h>
18 #include <abi/reg_ops.h>
19 #include <abi/regdef.h>
20 #ifdef CONFIG_CPU_HAS_FPU
25 unsigned long udelay_val;
26 unsigned long asid_cache;
28 * Capability and feature descriptor structure for CSKY CPU
30 unsigned long options;
31 unsigned int processor_id[4];
33 } __aligned(SMP_CACHE_BYTES);
35 extern struct cpuinfo_csky cpu_data[];
38 * User space process size: 2GB. This is hardcoded into a few places,
39 * so don't change it unless you know what you are doing. TASK_SIZE
40 * for a 64 bit kernel expandable to 8192EB, of which the current CSKY
41 * implementations will "only" be able to use 1TB ...
43 #define TASK_SIZE 0x7fff8000UL
46 #define STACK_TOP TASK_SIZE
47 #define STACK_TOP_MAX STACK_TOP
50 /* This decides where the kernel will search for a free chunk of vm
51 * space during mmap's.
53 #define TASK_UNMAPPED_BASE (TASK_SIZE / 3)
55 struct thread_struct {
56 unsigned long ksp; /* kernel stack pointer */
57 unsigned long sr; /* saved status register */
58 unsigned long esp0; /* points to SR of stack frame */
62 /* Other stuff associated with the thread. */
63 unsigned long address; /* Last user fault */
64 unsigned long error_code;
67 struct user_fp __aligned(16) user_fp;
70 #define INIT_THREAD { \
71 .ksp = (unsigned long) init_thread_union.stack + THREAD_SIZE, \
72 .sr = DEFAULT_PSR_VALUE, \
76 * Do necessary setup to start up a newly executed thread.
78 * pass the data segment into user programs if it exists,
79 * it can't hurt anything as far as I can tell
81 #define start_thread(_regs, _pc, _usp) \
83 set_fs(USER_DS); /* reads from user space */ \
84 (_regs)->pc = (_pc); \
85 (_regs)->regs[1] = 0; /* ABIV1 is R7, uClibc_main rtdl arg */ \
86 (_regs)->regs[2] = 0; \
87 (_regs)->regs[3] = 0; /* ABIV2 is R7, use it? */ \
88 (_regs)->sr &= ~PS_S; \
89 (_regs)->usp = (_usp); \
92 /* Forward declaration, a strange C thing */
95 /* Free all resources held by a thread. */
96 static inline void release_thread(struct task_struct *dead_task)
100 /* Prepare to copy thread state - unlazy all lazy status */
101 #define prepare_to_copy(tsk) do { } while (0)
103 extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
105 #define copy_segments(tsk, mm) do { } while (0)
106 #define release_segments(mm) do { } while (0)
107 #define forget_segments() do { } while (0)
109 extern unsigned long thread_saved_pc(struct task_struct *tsk);
111 unsigned long get_wchan(struct task_struct *p);
113 #define KSTK_EIP(tsk) (task_pt_regs(tsk)->pc)
114 #define KSTK_ESP(tsk) (task_pt_regs(tsk)->usp)
116 #define task_pt_regs(p) \
117 ((struct pt_regs *)(THREAD_SIZE + p->stack) - 1)
119 #define cpu_relax() barrier()
121 #endif /* __ASM_CSKY_PROCESSOR_H */