xref: /rk3399_ARM-atf/plat/nvidia/tegra/common/tegra_fiq_glue.c (revision c948f77136c42a92d0bb660543a3600c36dcf7f1)
1 /*
2  * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <assert.h>
8 
9 #include <arch_helpers.h>
10 #include <bl31/interrupt_mgmt.h>
11 #include <common/bl_common.h>
12 #include <common/debug.h>
13 #include <context.h>
14 #include <denver.h>
15 #include <lib/bakery_lock.h>
16 #include <lib/el3_runtime/context_mgmt.h>
17 #include <plat/common/platform.h>
18 
19 #include <tegra_def.h>
20 #include <tegra_private.h>
21 
22 static DEFINE_BAKERY_LOCK(tegra_fiq_lock);
23 
24 /*******************************************************************************
25  * Static variables
26  ******************************************************************************/
27 static uint64_t ns_fiq_handler_addr;
28 static uint32_t fiq_handler_active;
29 static pcpu_fiq_state_t fiq_state[PLATFORM_CORE_COUNT];
30 
31 /*******************************************************************************
32  * Handler for FIQ interrupts
33  ******************************************************************************/
34 static uint64_t tegra_fiq_interrupt_handler(uint32_t id,
35 					  uint32_t flags,
36 					  void *handle,
37 					  void *cookie)
38 {
39 	cpu_context_t *ctx = cm_get_context(NON_SECURE);
40 	el3_state_t *el3state_ctx = get_el3state_ctx(ctx);
41 	uint32_t cpu = plat_my_core_pos();
42 	uint32_t irq;
43 
44 	(void)id;
45 	(void)flags;
46 	(void)handle;
47 	(void)cookie;
48 
49 	bakery_lock_get(&tegra_fiq_lock);
50 
51 	/*
52 	 * The FIQ was generated when the execution was in the non-secure
53 	 * world. Save the context registers to start with.
54 	 */
55 	cm_el1_sysregs_context_save(NON_SECURE);
56 
57 	/*
58 	 * Save elr_el3 and spsr_el3 from the saved context, and overwrite
59 	 * the context with the NS fiq_handler_addr and SPSR value.
60 	 */
61 	fiq_state[cpu].elr_el3 = read_ctx_reg((el3state_ctx), (uint32_t)(CTX_ELR_EL3));
62 	fiq_state[cpu].spsr_el3 = read_ctx_reg((el3state_ctx), (uint32_t)(CTX_SPSR_EL3));
63 
64 	/*
65 	 * Set the new ELR to continue execution in the NS world using the
66 	 * FIQ handler registered earlier.
67 	 */
68 	assert(ns_fiq_handler_addr);
69 	write_ctx_reg((el3state_ctx), (uint32_t)(CTX_ELR_EL3), (ns_fiq_handler_addr));
70 
71 	/*
72 	 * Mark this interrupt as complete to avoid a FIQ storm.
73 	 */
74 	irq = plat_ic_acknowledge_interrupt();
75 	if (irq < 1022U) {
76 		plat_ic_end_of_interrupt(irq);
77 	}
78 
79 	bakery_lock_release(&tegra_fiq_lock);
80 
81 	return 0;
82 }
83 
84 /*******************************************************************************
85  * Setup handler for FIQ interrupts
86  ******************************************************************************/
87 void tegra_fiq_handler_setup(void)
88 {
89 	uint32_t flags;
90 	int32_t rc;
91 
92 	/* return if already registered */
93 	if (fiq_handler_active == 0U) {
94 		/*
95 		 * Register an interrupt handler for FIQ interrupts generated for
96 		 * NS interrupt sources
97 		 */
98 		flags = 0U;
99 		set_interrupt_rm_flag((flags), (NON_SECURE));
100 		rc = register_interrupt_type_handler(INTR_TYPE_EL3,
101 					tegra_fiq_interrupt_handler,
102 					flags);
103 		if (rc != 0) {
104 			panic();
105 		}
106 
107 		/* handler is now active */
108 		fiq_handler_active = 1;
109 	}
110 }
111 
112 /*******************************************************************************
113  * Validate and store NS world's entrypoint for FIQ interrupts
114  ******************************************************************************/
115 void tegra_fiq_set_ns_entrypoint(uint64_t entrypoint)
116 {
117 	ns_fiq_handler_addr = entrypoint;
118 }
119 
120 /*******************************************************************************
121  * Handler to return the NS EL1/EL0 CPU context
122  ******************************************************************************/
123 int32_t tegra_fiq_get_intr_context(void)
124 {
125 	cpu_context_t *ctx = cm_get_context(NON_SECURE);
126 	gp_regs_t *gpregs_ctx = get_gpregs_ctx(ctx);
127 	const el1_sys_regs_t *el1state_ctx = get_sysregs_ctx(ctx);
128 	uint32_t cpu = plat_my_core_pos();
129 	uint64_t val;
130 
131 	/*
132 	 * We store the ELR_EL3, SPSR_EL3, SP_EL0 and SP_EL1 registers so
133 	 * that el3_exit() sends these values back to the NS world.
134 	 */
135 	write_ctx_reg((gpregs_ctx), (uint32_t)(CTX_GPREG_X0), (fiq_state[cpu].elr_el3));
136 	write_ctx_reg((gpregs_ctx), (uint32_t)(CTX_GPREG_X1), (fiq_state[cpu].spsr_el3));
137 
138 	val = read_ctx_reg((gpregs_ctx), (uint32_t)(CTX_GPREG_SP_EL0));
139 	write_ctx_reg((gpregs_ctx), (uint32_t)(CTX_GPREG_X2), (val));
140 
141 	val = read_ctx_reg((el1state_ctx), (uint32_t)(CTX_SP_EL1));
142 	write_ctx_reg((gpregs_ctx), (uint32_t)(CTX_GPREG_X3), (val));
143 
144 	return 0;
145 }
146