2 * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
3 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
10 #ifndef __ASM_ARC_ENTRY_H
11 #define __ASM_ARC_ENTRY_H
13 #include <asm/unistd.h> /* For NR_syscalls defination */
14 #include <asm/arcregs.h>
15 #include <asm/ptrace.h>
16 #include <asm/processor.h> /* For VMALLOC_START */
19 #ifdef CONFIG_ISA_ARCOMPACT
20 #include <asm/entry-compact.h> /* ISA specific bits */
22 #include <asm/entry-arcv2.h>
25 /* Note on the LD/ST addr modes with addr reg wback
29 * LD.a reg1, [reg2, x] => Pre Incr
30 * Eff Addr for load = [reg2 + x]
32 * LD.ab reg1, [reg2, x] => Post Incr
33 * Eff Addr for load = [reg2]
54 /*--------------------------------------------------------------
55 * Helpers to save/restore Scratch Regs:
56 * used by Interrupt/Exception Prologue/Epilogue
57 *-------------------------------------------------------------*/
74 .macro RESTORE_R12_TO_R0
89 #ifdef CONFIG_ARC_CURR_IN_REG
94 /*--------------------------------------------------------------
95 * Helpers to save/restore callee-saved regs:
96 * used by several macros below
97 *-------------------------------------------------------------*/
98 .macro SAVE_R13_TO_R24
113 .macro RESTORE_R24_TO_R13
128 #define OFF_USER_R25_FROM_R24 (SZ_CALLEE_REGS + SZ_PT_REGS - 8)/4
130 /*--------------------------------------------------------------
131 * Collect User Mode callee regs as struct callee_regs - needed by
132 * fork/do_signal/unaligned-access-emulation.
133 * (By default only scratch regs are saved on entry to kernel)
135 * Special handling for r25 if used for caching Task Pointer.
136 * It would have been saved in task->thread.user_r25 already, but to keep
137 * the interface same it is copied into regular r25 placeholder in
138 * struct callee_regs.
139 *-------------------------------------------------------------*/
140 .macro SAVE_CALLEE_SAVED_USER
144 #ifdef CONFIG_ARC_CURR_IN_REG
145 ; Retrieve orig r25
and save it on stack
146 ld
.as r12
, [sp
, OFF_USER_R25_FROM_R24
]
154 /*--------------------------------------------------------------
155 * Save kernel Mode callee regs at the time of Contect Switch.
157 * Special handling for r25 if used for caching Task Pointer.
158 * Kernel simply skips saving it since it will be loaded with
159 * incoming task pointer anyways
160 *-------------------------------------------------------------*/
161 .macro SAVE_CALLEE_SAVED_KERNEL
165 #ifdef CONFIG_ARC_CURR_IN_REG
172 /*--------------------------------------------------------------
173 * Opposite of SAVE_CALLEE_SAVED_KERNEL
174 *-------------------------------------------------------------*/
175 .macro RESTORE_CALLEE_SAVED_KERNEL
177 #ifdef CONFIG_ARC_CURR_IN_REG
178 add sp
, sp
, 4 /* skip usual r25 placeholder */
185 /*--------------------------------------------------------------
186 * Opposite of SAVE_CALLEE_SAVED_USER
188 * ptrace tracer or unaligned-access fixup might have changed a user mode
189 * callee reg which is saved back to usual r25 storage location
190 *-------------------------------------------------------------*/
191 .macro RESTORE_CALLEE_SAVED_USER
193 #ifdef CONFIG_ARC_CURR_IN_REG
195 st
.as r12
, [sp
, OFF_USER_R25_FROM_R24
]
202 /*--------------------------------------------------------------
203 * Super FAST Restore callee saved regs by simply re-adjusting SP
204 *-------------------------------------------------------------*/
205 .macro DISCARD_CALLEE_SAVED_USER
206 add sp
, sp
, SZ_CALLEE_REGS
209 /*-------------------------------------------------------------
210 * given a tsk struct, get to the base of it's kernel mode stack
211 * tsk->thread_info is really a PAGE, whose bottom hoists stack
212 * which grows upwards towards thread_info
213 *------------------------------------------------------------*/
215 .macro GET_TSK_STACK_BASE tsk
, out
217 /* Get task->thread_info (this is essentially start of a PAGE) */
218 ld \out
, [\tsk
, TASK_THREAD_INFO
]
220 /* Go to end of page where stack begins (grows upwards) */
221 add2 \out
, \out
, (THREAD_SIZE
)/4
226 * @reg [OUT] thread_info->flags of "current"
228 .macro GET_CURR_THR_INFO_FLAGS reg
229 GET_CURR_THR_INFO_FROM_SP
\reg
230 ld
\reg
, [\reg
, THREAD_INFO_FLAGS
]
235 /*-------------------------------------------------
236 * Retrieve the current running task on this CPU
237 * 1. Determine curr CPU id.
238 * 2. Use it to index into _current_task[ ]
240 .macro GET_CURR_TASK_ON_CPU reg
242 ld
.as
\reg
, [@_current_task
, \reg
]
245 /*-------------------------------------------------
246 * Save a new task as the "current" task on this CPU
247 * 1. Determine curr CPU id.
248 * 2. Use it to index into _current_task[ ]
250 * Coded differently than GET_CURR_TASK_ON_CPU (which uses LD.AS)
251 * because ST r0, [r1, offset] can ONLY have s9 @offset
252 * while LD can take s9 (4 byte insn) or LIMM (8 byte insn)
255 .macro SET_CURR_TASK_ON_CPU tsk
, tmp
257 add2
\tmp
, @_current_task
, \tmp
259 #ifdef CONFIG_ARC_CURR_IN_REG
266 #else /* Uniprocessor implementation of macros */
268 .macro GET_CURR_TASK_ON_CPU reg
269 ld
\reg
, [@_current_task
]
272 .macro SET_CURR_TASK_ON_CPU tsk
, tmp
273 st
\tsk
, [@_current_task
]
274 #ifdef CONFIG_ARC_CURR_IN_REG
279 #endif /* SMP / UNI */
281 /* ------------------------------------------------------------------
282 * Get the ptr to some field of Current Task at @off in task struct
283 * -Uses r25 for Current task ptr if that is enabled
286 #ifdef CONFIG_ARC_CURR_IN_REG
288 .macro GET_CURR_TASK_FIELD_PTR off
, reg
294 .macro GET_CURR_TASK_FIELD_PTR off
, reg
295 GET_CURR_TASK_ON_CPU
\reg
299 #endif /* CONFIG_ARC_CURR_IN_REG */
301 #endif /* __ASM_ARC_ENTRY_H */