xref: /rk3399_ARM-atf/plat/imx/common/imx9_sm_sema.c (revision 480e8dd9df291cc0e31695983fa6ff235e1671cd)
1*f7e7ea1fSRanjani Vaidyanathan /*
2*f7e7ea1fSRanjani Vaidyanathan  * Copyright 2023-2025 NXP
3*f7e7ea1fSRanjani Vaidyanathan  *
4*f7e7ea1fSRanjani Vaidyanathan  * SPDX-License-Identifier: BSD-3-Clause
5*f7e7ea1fSRanjani Vaidyanathan  */
6*f7e7ea1fSRanjani Vaidyanathan 
7*f7e7ea1fSRanjani Vaidyanathan #include <assert.h>
8*f7e7ea1fSRanjani Vaidyanathan #include <stdint.h>
9*f7e7ea1fSRanjani Vaidyanathan 
10*f7e7ea1fSRanjani Vaidyanathan #include <platform_def.h>
11*f7e7ea1fSRanjani Vaidyanathan 
12*f7e7ea1fSRanjani Vaidyanathan typedef struct {
13*f7e7ea1fSRanjani Vaidyanathan 	uint8_t flag_sm;
14*f7e7ea1fSRanjani Vaidyanathan 	uint8_t flag_ap;
15*f7e7ea1fSRanjani Vaidyanathan 	uint8_t flag_unused1;
16*f7e7ea1fSRanjani Vaidyanathan 	uint8_t flag_unused2;
17*f7e7ea1fSRanjani Vaidyanathan 	uint32_t turn;
18*f7e7ea1fSRanjani Vaidyanathan } sm_ap_semaphore_t;
19*f7e7ea1fSRanjani Vaidyanathan 
20*f7e7ea1fSRanjani Vaidyanathan /* Used for GIC_WAKER sync between AP and SM. */
request_sm_ap_sema(void)21*f7e7ea1fSRanjani Vaidyanathan void request_sm_ap_sema(void)
22*f7e7ea1fSRanjani Vaidyanathan {
23*f7e7ea1fSRanjani Vaidyanathan 	volatile sm_ap_semaphore_t *sm_ap_sema = (sm_ap_semaphore_t *)SM_AP_SEMA_ADDR;
24*f7e7ea1fSRanjani Vaidyanathan 
25*f7e7ea1fSRanjani Vaidyanathan 	sm_ap_sema->flag_ap = 1U;
26*f7e7ea1fSRanjani Vaidyanathan 	sm_ap_sema->turn = 0U;
27*f7e7ea1fSRanjani Vaidyanathan 
28*f7e7ea1fSRanjani Vaidyanathan 	while (sm_ap_sema->flag_sm && sm_ap_sema->turn == 0U) {
29*f7e7ea1fSRanjani Vaidyanathan 		/* Wait for SM to be done in the critical section. */
30*f7e7ea1fSRanjani Vaidyanathan 		;
31*f7e7ea1fSRanjani Vaidyanathan 	}
32*f7e7ea1fSRanjani Vaidyanathan }
33*f7e7ea1fSRanjani Vaidyanathan 
34*f7e7ea1fSRanjani Vaidyanathan /* Used for GIC_WAKER sync between AP and SM. */
release_sm_ap_sema(void)35*f7e7ea1fSRanjani Vaidyanathan void release_sm_ap_sema(void)
36*f7e7ea1fSRanjani Vaidyanathan {
37*f7e7ea1fSRanjani Vaidyanathan 	sm_ap_semaphore_t *sm_ap_sema = (sm_ap_semaphore_t *)SM_AP_SEMA_ADDR;
38*f7e7ea1fSRanjani Vaidyanathan 
39*f7e7ea1fSRanjani Vaidyanathan 	sm_ap_sema->flag_ap = 0U;
40*f7e7ea1fSRanjani Vaidyanathan }
41*f7e7ea1fSRanjani Vaidyanathan 
42