xref: /nrf52832-nimble/rt-thread/libcpu/arm/am335x/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 * 2013-07-05     Bernard      the first version
9*10465441SEvalZero */
10*10465441SEvalZero
11*10465441SEvalZero/*
12*10465441SEvalZero * rt_base_t rt_hw_interrupt_disable();
13*10465441SEvalZero */
14*10465441SEvalZero.globl rt_hw_interrupt_disable
15*10465441SEvalZerort_hw_interrupt_disable:
16*10465441SEvalZero    mrs r0, cpsr
17*10465441SEvalZero    cpsid if
18*10465441SEvalZero    bx  lr
19*10465441SEvalZero
20*10465441SEvalZero/*
21*10465441SEvalZero * void rt_hw_interrupt_enable(rt_base_t level);
22*10465441SEvalZero */
23*10465441SEvalZero.globl rt_hw_interrupt_enable
24*10465441SEvalZerort_hw_interrupt_enable:
25*10465441SEvalZero    msr cpsr_c, r0
26*10465441SEvalZero    bx  lr
27*10465441SEvalZero
28*10465441SEvalZero/*
29*10465441SEvalZero * void rt_hw_context_switch(rt_uint32 from, rt_uint32 to);
30*10465441SEvalZero * r0 --> from
31*10465441SEvalZero * r1 --> to
32*10465441SEvalZero */
33*10465441SEvalZero.globl rt_hw_context_switch
34*10465441SEvalZerort_hw_context_switch:
35*10465441SEvalZero    stmfd   sp!, {lr}       @ push pc (lr should be pushed in place of PC)
36*10465441SEvalZero    stmfd   sp!, {r0-r12, lr}   @ push lr & register file
37*10465441SEvalZero
38*10465441SEvalZero    mrs r4, cpsr
39*10465441SEvalZero    tst lr, #0x01
40*10465441SEvalZero    orrne r4, r4, #0x20     @ it's thumb code
41*10465441SEvalZero
42*10465441SEvalZero    stmfd sp!, {r4}         @ push cpsr
43*10465441SEvalZero
44*10465441SEvalZero    str sp, [r0]            @ store sp in preempted tasks TCB
45*10465441SEvalZero    ldr sp, [r1]            @ get new task stack pointer
46*10465441SEvalZero
47*10465441SEvalZero    ldmfd sp!, {r4}         @ pop new task cpsr to spsr
48*10465441SEvalZero    msr spsr_cxsf, r4
49*10465441SEvalZero
50*10465441SEvalZero_do_switch:
51*10465441SEvalZero    ldmfd sp!, {r0-r12, lr, pc}^  @ pop new task r0-r12, lr & pc, copy spsr to cpsr
52*10465441SEvalZero
53*10465441SEvalZero/*
54*10465441SEvalZero * void rt_hw_context_switch_to(rt_uint32 to);
55*10465441SEvalZero * r0 --> to
56*10465441SEvalZero */
57*10465441SEvalZero.globl rt_hw_context_switch_to
58*10465441SEvalZerort_hw_context_switch_to:
59*10465441SEvalZero    ldr sp, [r0]            @ get new task stack pointer
60*10465441SEvalZero
61*10465441SEvalZero    ldmfd sp!, {r4}         @ pop new task spsr
62*10465441SEvalZero    msr spsr_cxsf, r4
63*10465441SEvalZero
64*10465441SEvalZero    bic r4, r4, #0x20       @ must be ARM mode
65*10465441SEvalZero    msr cpsr_cxsf, r4
66*10465441SEvalZero
67*10465441SEvalZero    ldmfd sp!, {r0-r12, lr, pc}^   @ pop new task r0-r12, lr & pc
68*10465441SEvalZero
69*10465441SEvalZero/*
70*10465441SEvalZero * void rt_hw_context_switch_interrupt(rt_uint32 from, rt_uint32 to);
71*10465441SEvalZero */
72*10465441SEvalZero.globl rt_thread_switch_interrupt_flag
73*10465441SEvalZero.globl rt_interrupt_from_thread
74*10465441SEvalZero.globl rt_interrupt_to_thread
75*10465441SEvalZero.globl rt_hw_context_switch_interrupt
76*10465441SEvalZerort_hw_context_switch_interrupt:
77*10465441SEvalZero    ldr r2, =rt_thread_switch_interrupt_flag
78*10465441SEvalZero    ldr r3, [r2]
79*10465441SEvalZero    cmp r3, #1
80*10465441SEvalZero    beq _reswitch
81*10465441SEvalZero    mov r3, #1              @ set rt_thread_switch_interrupt_flag to 1
82*10465441SEvalZero    str r3, [r2]
83*10465441SEvalZero    ldr r2, =rt_interrupt_from_thread   @ set rt_interrupt_from_thread
84*10465441SEvalZero    str r0, [r2]
85*10465441SEvalZero_reswitch:
86*10465441SEvalZero    ldr r2, =rt_interrupt_to_thread     @ set rt_interrupt_to_thread
87*10465441SEvalZero    str r1, [r2]
88*10465441SEvalZero    bx  lr
89