xref: /rk3399_ARM-atf/plat/nvidia/tegra/common/tegra_fiq_glue.c (revision 09d40e0e08283a249e7dce0e106c07c5141f9b7e)
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 	bakery_lock_get(&tegra_fiq_lock);
45 
46 	/*
47 	 * The FIQ was generated when the execution was in the non-secure
48 	 * world. Save the context registers to start with.
49 	 */
50 	cm_el1_sysregs_context_save(NON_SECURE);
51 
52 	/*
53 	 * Save elr_el3 and spsr_el3 from the saved context, and overwrite
54 	 * the context with the NS fiq_handler_addr and SPSR value.
55 	 */
56 	fiq_state[cpu].elr_el3 = read_ctx_reg((el3state_ctx), (uint32_t)(CTX_ELR_EL3));
57 	fiq_state[cpu].spsr_el3 = read_ctx_reg((el3state_ctx), (uint32_t)(CTX_SPSR_EL3));
58 
59 	/*
60 	 * Set the new ELR to continue execution in the NS world using the
61 	 * FIQ handler registered earlier.
62 	 */
63 	assert(ns_fiq_handler_addr);
64 	write_ctx_reg((el3state_ctx), (uint32_t)(CTX_ELR_EL3), (ns_fiq_handler_addr));
65 
66 	/*
67 	 * Mark this interrupt as complete to avoid a FIQ storm.
68 	 */
69 	irq = plat_ic_acknowledge_interrupt();
70 	if (irq < 1022U) {
71 		plat_ic_end_of_interrupt(irq);
72 	}
73 
74 	bakery_lock_release(&tegra_fiq_lock);
75 
76 	return 0;
77 }
78 
79 /*******************************************************************************
80  * Setup handler for FIQ interrupts
81  ******************************************************************************/
82 void tegra_fiq_handler_setup(void)
83 {
84 	uint32_t flags;
85 	int32_t rc;
86 
87 	/* return if already registered */
88 	if (fiq_handler_active == 0U) {
89 		/*
90 		 * Register an interrupt handler for FIQ interrupts generated for
91 		 * NS interrupt sources
92 		 */
93 		flags = 0U;
94 		set_interrupt_rm_flag((flags), (NON_SECURE));
95 		rc = register_interrupt_type_handler(INTR_TYPE_EL3,
96 					tegra_fiq_interrupt_handler,
97 					flags);
98 		if (rc != 0) {
99 			panic();
100 		}
101 
102 		/* handler is now active */
103 		fiq_handler_active = 1;
104 	}
105 }
106 
107 /*******************************************************************************
108  * Validate and store NS world's entrypoint for FIQ interrupts
109  ******************************************************************************/
110 void tegra_fiq_set_ns_entrypoint(uint64_t entrypoint)
111 {
112 	ns_fiq_handler_addr = entrypoint;
113 }
114 
115 /*******************************************************************************
116  * Handler to return the NS EL1/EL0 CPU context
117  ******************************************************************************/
118 int32_t tegra_fiq_get_intr_context(void)
119 {
120 	cpu_context_t *ctx = cm_get_context(NON_SECURE);
121 	gp_regs_t *gpregs_ctx = get_gpregs_ctx(ctx);
122 	const el1_sys_regs_t *el1state_ctx = get_sysregs_ctx(ctx);
123 	uint32_t cpu = plat_my_core_pos();
124 	uint64_t val;
125 
126 	/*
127 	 * We store the ELR_EL3, SPSR_EL3, SP_EL0 and SP_EL1 registers so
128 	 * that el3_exit() sends these values back to the NS world.
129 	 */
130 	write_ctx_reg((gpregs_ctx), (uint32_t)(CTX_GPREG_X0), (fiq_state[cpu].elr_el3));
131 	write_ctx_reg((gpregs_ctx), (uint32_t)(CTX_GPREG_X1), (fiq_state[cpu].spsr_el3));
132 
133 	val = read_ctx_reg((gpregs_ctx), (uint32_t)(CTX_GPREG_SP_EL0));
134 	write_ctx_reg((gpregs_ctx), (uint32_t)(CTX_GPREG_X2), (val));
135 
136 	val = read_ctx_reg((el1state_ctx), (uint32_t)(CTX_SP_EL1));
137 	write_ctx_reg((gpregs_ctx), (uint32_t)(CTX_GPREG_X3), (val));
138 
139 	return 0;
140 }
141