1 /* SPDX-License-Identifier: GPL-2.0 */ 2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. 3 4 #ifndef __ASM_CSKY_PROCESSOR_H 5 #define __ASM_CSKY_PROCESSOR_H 6 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 #include <abi/switch_context.h> 15 #ifdef CONFIG_CPU_HAS_FPU 16 #include <abi/fpu.h> 17 #endif 18 19 struct cpuinfo_csky { 20 unsigned long asid_cache; 21 } __aligned(SMP_CACHE_BYTES); 22 23 extern struct cpuinfo_csky cpu_data[]; 24 25 /* 26 * User space process size: 2GB. This is hardcoded into a few places, 27 * so don't change it unless you know what you are doing. TASK_SIZE 28 * for a 64 bit kernel expandable to 8192EB, of which the current CSKY 29 * implementations will "only" be able to use 1TB ... 30 */ 31 #define TASK_SIZE 0x7fff8000UL 32 33 #ifdef __KERNEL__ 34 #define STACK_TOP TASK_SIZE 35 #define STACK_TOP_MAX STACK_TOP 36 #endif 37 38 /* This decides where the kernel will search for a free chunk of vm 39 * space during mmap's. 40 */ 41 #define TASK_UNMAPPED_BASE (TASK_SIZE / 3) 42 43 struct thread_struct { 44 unsigned long sp; /* kernel stack pointer */ 45 unsigned long trap_no; /* saved status register */ 46 47 /* FPU regs */ 48 struct user_fp __aligned(16) user_fp; 49 }; 50 51 #define INIT_THREAD { \ 52 .sp = sizeof(init_stack) + (unsigned long) &init_stack, \ 53 } 54 55 /* 56 * Do necessary setup to start up a newly executed thread. 57 * 58 * pass the data segment into user programs if it exists, 59 * it can't hurt anything as far as I can tell 60 */ 61 #define start_thread(_regs, _pc, _usp) \ 62 do { \ 63 set_fs(USER_DS); /* reads from user space */ \ 64 (_regs)->pc = (_pc); \ 65 (_regs)->regs[1] = 0; /* ABIV1 is R7, uClibc_main rtdl arg */ \ 66 (_regs)->regs[2] = 0; \ 67 (_regs)->regs[3] = 0; /* ABIV2 is R7, use it? */ \ 68 (_regs)->sr &= ~PS_S; \ 69 (_regs)->usp = (_usp); \ 70 } while (0) 71 72 /* Forward declaration, a strange C thing */ 73 struct task_struct; 74 75 /* Free all resources held by a thread. */ 76 static inline void release_thread(struct task_struct *dead_task) 77 { 78 } 79 80 /* Prepare to copy thread state - unlazy all lazy status */ 81 #define prepare_to_copy(tsk) do { } while (0) 82 83 extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); 84 85 #define copy_segments(tsk, mm) do { } while (0) 86 #define release_segments(mm) do { } while (0) 87 #define forget_segments() do { } while (0) 88 89 extern unsigned long thread_saved_pc(struct task_struct *tsk); 90 91 unsigned long get_wchan(struct task_struct *p); 92 93 #define KSTK_EIP(tsk) (task_pt_regs(tsk)->pc) 94 #define KSTK_ESP(tsk) (task_pt_regs(tsk)->usp) 95 96 #define task_pt_regs(p) \ 97 ((struct pt_regs *)(THREAD_SIZE + task_stack_page(p)) - 1) 98 99 #define cpu_relax() barrier() 100 101 #endif /* __ASM_CSKY_PROCESSOR_H */ 102