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
7 #include <linux/bitops.h>
8 #include <asm/segment.h>
9 #include <asm/ptrace.h>
10 #include <asm/current.h>
11 #include <asm/cache.h>
12 #include <abi/reg_ops.h>
13 #include <abi/regdef.h>
14 #ifdef CONFIG_CPU_HAS_FPU
19 unsigned long udelay_val;
20 unsigned long asid_cache;
22 * Capability and feature descriptor structure for CSKY CPU
24 unsigned long options;
25 unsigned int processor_id[4];
27 } __aligned(SMP_CACHE_BYTES);
29 extern struct cpuinfo_csky cpu_data[];
32 * User space process size: 2GB. This is hardcoded into a few places,
33 * so don't change it unless you know what you are doing. TASK_SIZE
34 * for a 64 bit kernel expandable to 8192EB, of which the current CSKY
35 * implementations will "only" be able to use 1TB ...
37 #define TASK_SIZE 0x7fff8000UL
40 #define STACK_TOP TASK_SIZE
41 #define STACK_TOP_MAX STACK_TOP
44 /* This decides where the kernel will search for a free chunk of vm
45 * space during mmap's.
47 #define TASK_UNMAPPED_BASE (TASK_SIZE / 3)
49 struct thread_struct {
50 unsigned long ksp; /* kernel stack pointer */
51 unsigned long sr; /* saved status register */
52 unsigned long esp0; /* points to SR of stack frame */
56 /* Other stuff associated with the thread. */
57 unsigned long address; /* Last user fault */
58 unsigned long error_code;
61 struct user_fp __aligned(16) user_fp;
64 #define INIT_THREAD { \
65 .ksp = (unsigned long) init_thread_union.stack + THREAD_SIZE, \
66 .sr = DEFAULT_PSR_VALUE, \
70 * Do necessary setup to start up a newly executed thread.
72 * pass the data segment into user programs if it exists,
73 * it can't hurt anything as far as I can tell
75 #define start_thread(_regs, _pc, _usp) \
77 set_fs(USER_DS); /* reads from user space */ \
78 (_regs)->pc = (_pc); \
79 (_regs)->regs[1] = 0; /* ABIV1 is R7, uClibc_main rtdl arg */ \
80 (_regs)->regs[2] = 0; \
81 (_regs)->regs[3] = 0; /* ABIV2 is R7, use it? */ \
82 (_regs)->sr &= ~PS_S; \
83 (_regs)->usp = (_usp); \
86 /* Forward declaration, a strange C thing */
89 /* Free all resources held by a thread. */
90 static inline void release_thread(struct task_struct *dead_task)
94 /* Prepare to copy thread state - unlazy all lazy status */
95 #define prepare_to_copy(tsk) do { } while (0)
97 extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags);
99 #define copy_segments(tsk, mm) do { } while (0)
100 #define release_segments(mm) do { } while (0)
101 #define forget_segments() do { } while (0)
103 extern unsigned long thread_saved_pc(struct task_struct *tsk);
105 unsigned long get_wchan(struct task_struct *p);
107 #define KSTK_EIP(tsk) (task_pt_regs(tsk)->pc)
108 #define KSTK_ESP(tsk) (task_pt_regs(tsk)->usp)
110 #define task_pt_regs(p) \
111 ((struct pt_regs *)(THREAD_SIZE + p->stack) - 1)
113 #define cpu_relax() barrier()
115 #endif /* __ASM_CSKY_PROCESSOR_H */