1/*
2 *  Port on Texas Instruments TMS320C6x architecture
3 *
4 *  Copyright (C) 2004, 2009, 2010, 2011 Texas Instruments Incorporated
5 *  Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com)
6 *
7 *  Updated for 2.6.34: Mark Salter <msalter@redhat.com>
8 *
9 *  This program is free software; you can redistribute it and/or modify
10 *  it under the terms of the GNU General Public License version 2 as
11 *  published by the Free Software Foundation.
12 */
13#ifndef _ASM_C6X_PROCESSOR_H
14#define _ASM_C6X_PROCESSOR_H
15
16#include <asm/ptrace.h>
17#include <asm/page.h>
18#include <asm/current.h>
19
20/*
21 * Default implementation of macro that returns current
22 * instruction pointer ("program counter").
23 */
24#define current_text_addr()			\
25({						\
26	void *__pc;				\
27	asm("mvc .S2 pce1,%0\n" : "=b"(__pc));	\
28	__pc;					\
29})
30
31/*
32 * User space process size. This is mostly meaningless for NOMMU
33 * but some C6X processors may have RAM addresses up to 0xFFFFFFFF.
34 * Since calls like mmap() can return an address or an error, we
35 * have to allow room for error returns when code does something
36 * like:
37 *
38 *       addr = do_mmap(...)
39 *       if ((unsigned long)addr >= TASK_SIZE)
40 *            ... its an error code, not an address ...
41 *
42 * Here, we allow for 4096 error codes which means we really can't
43 * use the last 4K page on systems with RAM extending all the way
44 * to the end of the 32-bit address space.
45 */
46#define TASK_SIZE	0xFFFFF000
47
48/*
49 * This decides where the kernel will search for a free chunk of vm
50 * space during mmap's. We won't be using it
51 */
52#define TASK_UNMAPPED_BASE	0
53
54struct thread_struct {
55	unsigned long long b15_14;
56	unsigned long long a15_14;
57	unsigned long long b13_12;
58	unsigned long long a13_12;
59	unsigned long long b11_10;
60	unsigned long long a11_10;
61	unsigned long long ricl_icl;
62	unsigned long  usp;		/* user stack pointer */
63	unsigned long  pc;		/* kernel pc */
64	unsigned long  wchan;
65};
66
67#define INIT_THREAD					\
68{							\
69	.usp = 0,					\
70	.wchan = 0,					\
71}
72
73#define INIT_MMAP { \
74	&init_mm, 0, 0, NULL, PAGE_SHARED, VM_READ | VM_WRITE | VM_EXEC, 1, \
75	NULL, NULL }
76
77#define task_pt_regs(task) \
78	((struct pt_regs *)(THREAD_START_SP + task_stack_page(task)) - 1)
79
80#define alloc_kernel_stack()	__get_free_page(GFP_KERNEL)
81#define free_kernel_stack(page) free_page((page))
82
83
84/* Forward declaration, a strange C thing */
85struct task_struct;
86
87extern void start_thread(struct pt_regs *regs, unsigned int pc,
88			 unsigned long usp);
89
90/* Free all resources held by a thread. */
91static inline void release_thread(struct task_struct *dead_task)
92{
93}
94
95#define copy_segments(tsk, mm)		do { } while (0)
96#define release_segments(mm)		do { } while (0)
97
98/*
99 * saved PC of a blocked thread.
100 */
101#define thread_saved_pc(tsk) (task_pt_regs(tsk)->pc)
102
103/*
104 * saved kernel SP and DP of a blocked thread.
105 */
106#ifdef _BIG_ENDIAN
107#define thread_saved_ksp(tsk) \
108	(*(unsigned long *)&(tsk)->thread.b15_14)
109#define thread_saved_dp(tsk) \
110	(*(((unsigned long *)&(tsk)->thread.b15_14) + 1))
111#else
112#define thread_saved_ksp(tsk) \
113	(*(((unsigned long *)&(tsk)->thread.b15_14) + 1))
114#define thread_saved_dp(tsk) \
115	(*(unsigned long *)&(tsk)->thread.b15_14)
116#endif
117
118extern unsigned long get_wchan(struct task_struct *p);
119
120#define KSTK_EIP(task)	(task_pt_regs(task)->pc)
121#define KSTK_ESP(task)	(task_pt_regs(task)->sp)
122
123#define cpu_relax()		do { } while (0)
124#define cpu_relax_lowlatency()        cpu_relax()
125
126extern const struct seq_operations cpuinfo_op;
127
128/* Reset the board */
129#define HARD_RESET_NOW()
130
131extern unsigned int c6x_core_freq;
132
133
134extern void (*c6x_restart)(void);
135extern void (*c6x_halt)(void);
136
137#endif /* ASM_C6X_PROCESSOR_H */
138