xref: /nrf52832-nimble/rt-thread/libcpu/arm/armv6/context_gcc.S (revision 104654410c56c573564690304ae786df310c91fc)
1*10465441SEvalZero/*
2*10465441SEvalZero * Copyright (c) 2006-2018, RT-Thread Development Team
3*10465441SEvalZero *
4*10465441SEvalZero * SPDX-License-Identifier: Apache-2.0
5*10465441SEvalZero *
6*10465441SEvalZero * Change Logs:
7*10465441SEvalZero * Date           Author       Notes
8*10465441SEvalZero * 2011-01-13     weety    copy from mini2440
9*10465441SEvalZero */
10*10465441SEvalZero
11*10465441SEvalZero/*!
12*10465441SEvalZero * \addtogroup ARMv6
13*10465441SEvalZero */
14*10465441SEvalZero/*@{*/
15*10465441SEvalZero
16*10465441SEvalZero#include <rtconfig.h>
17*10465441SEvalZero
18*10465441SEvalZero#define NOINT          0xc0
19*10465441SEvalZero#define FPEXC_EN       (1 << 30) /* VFP enable bit */
20*10465441SEvalZero
21*10465441SEvalZero/*
22*10465441SEvalZero * rt_base_t rt_hw_interrupt_disable();
23*10465441SEvalZero */
24*10465441SEvalZero.globl rt_hw_interrupt_disable
25*10465441SEvalZerort_hw_interrupt_disable:
26*10465441SEvalZero    mrs r0, cpsr
27*10465441SEvalZero    cpsid if
28*10465441SEvalZero    bx  lr
29*10465441SEvalZero
30*10465441SEvalZero/*
31*10465441SEvalZero * void rt_hw_interrupt_enable(rt_base_t level);
32*10465441SEvalZero */
33*10465441SEvalZero.globl rt_hw_interrupt_enable
34*10465441SEvalZerort_hw_interrupt_enable:
35*10465441SEvalZero    msr cpsr_c, r0
36*10465441SEvalZero    bx  lr
37*10465441SEvalZero
38*10465441SEvalZero/*
39*10465441SEvalZero * void rt_hw_context_switch(rt_uint32 from, rt_uint32 to);
40*10465441SEvalZero * r0 --> from
41*10465441SEvalZero * r1 --> to
42*10465441SEvalZero */
43*10465441SEvalZero.globl rt_hw_context_switch
44*10465441SEvalZerort_hw_context_switch:
45*10465441SEvalZero    stmfd   sp!, {lr}       @ push pc (lr should be pushed in place of PC)
46*10465441SEvalZero    stmfd   sp!, {r0-r12, lr}   @ push lr & register file
47*10465441SEvalZero
48*10465441SEvalZero    mrs r4, cpsr
49*10465441SEvalZero    tst lr, #0x01
50*10465441SEvalZero    orrne r4, r4, #0x20     @ it's thumb code
51*10465441SEvalZero
52*10465441SEvalZero    stmfd sp!, {r4}         @ push cpsr
53*10465441SEvalZero
54*10465441SEvalZero    str sp, [r0]            @ store sp in preempted tasks TCB
55*10465441SEvalZero    ldr sp, [r1]            @ get new task stack pointer
56*10465441SEvalZero
57*10465441SEvalZero    ldmfd sp!, {r4}         @ pop new task cpsr to spsr
58*10465441SEvalZero    msr spsr_cxsf, r4
59*10465441SEvalZero_do_switch:
60*10465441SEvalZero    ldmfd sp!, {r0-r12, lr, pc}^  @ pop new task r0-r12, lr & pc, copy spsr to cpsr
61*10465441SEvalZero
62*10465441SEvalZero/*
63*10465441SEvalZero * void rt_hw_context_switch_to(rt_uint32 to);
64*10465441SEvalZero * r0 --> to
65*10465441SEvalZero */
66*10465441SEvalZero.globl rt_hw_context_switch_to
67*10465441SEvalZerort_hw_context_switch_to:
68*10465441SEvalZero    ldr sp, [r0]            @ get new task stack pointer
69*10465441SEvalZero
70*10465441SEvalZero    ldmfd sp!, {r4}         @ pop new task spsr
71*10465441SEvalZero    msr spsr_cxsf, r4
72*10465441SEvalZero
73*10465441SEvalZero    bic r4, r4, #0x20       @ must be ARM mode
74*10465441SEvalZero    msr cpsr_cxsf, r4
75*10465441SEvalZero    ldmfd sp!, {r0-r12, lr, pc}^   @ pop new task r0-r12, lr & pc
76*10465441SEvalZero
77*10465441SEvalZero/*
78*10465441SEvalZero * void rt_hw_context_switch_interrupt(rt_uint32 from, rt_uint32 to);
79*10465441SEvalZero */
80*10465441SEvalZero.globl rt_thread_switch_interrupt_flag
81*10465441SEvalZero.globl rt_interrupt_from_thread
82*10465441SEvalZero.globl rt_interrupt_to_thread
83*10465441SEvalZero.globl rt_hw_context_switch_interrupt
84*10465441SEvalZerort_hw_context_switch_interrupt:
85*10465441SEvalZero    ldr r2, =rt_thread_switch_interrupt_flag
86*10465441SEvalZero    ldr r3, [r2]
87*10465441SEvalZero    cmp r3, #1
88*10465441SEvalZero    beq _reswitch
89*10465441SEvalZero    mov r3, #1              @ set rt_thread_switch_interrupt_flag to 1
90*10465441SEvalZero    str r3, [r2]
91*10465441SEvalZero    ldr r2, =rt_interrupt_from_thread   @ set rt_interrupt_from_thread
92*10465441SEvalZero    str r0, [r2]
93*10465441SEvalZero_reswitch:
94*10465441SEvalZero    ldr r2, =rt_interrupt_to_thread     @ set rt_interrupt_to_thread
95*10465441SEvalZero    str r1, [r2]
96*10465441SEvalZero    bx  lr
97