xref: /rk3399_ARM-atf/plat/nvidia/tegra/common/tegra_fiq_glue.c (revision 0b32628eddfef95b51909816f625e6f37cd21cb8)
1 /*
2  * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions are met:
6  *
7  * Redistributions of source code must retain the above copyright notice, this
8  * list of conditions and the following disclaimer.
9  *
10  * Redistributions in binary form must reproduce the above copyright notice,
11  * this list of conditions and the following disclaimer in the documentation
12  * and/or other materials provided with the distribution.
13  *
14  * Neither the name of ARM nor the names of its contributors may be used
15  * to endorse or promote products derived from this software without specific
16  * prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
22  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28  * POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #include <arch_helpers.h>
32 #include <assert.h>
33 #include <bakery_lock.h>
34 #include <bl_common.h>
35 #include <context.h>
36 #include <context_mgmt.h>
37 #include <debug.h>
38 #include <denver.h>
39 #include <gic_v2.h>
40 #include <interrupt_mgmt.h>
41 #include <platform.h>
42 #include <tegra_def.h>
43 #include <tegra_private.h>
44 
45 DEFINE_BAKERY_LOCK(tegra_fiq_lock);
46 
47 /*******************************************************************************
48  * Static variables
49  ******************************************************************************/
50 static uint64_t ns_fiq_handler_addr;
51 static unsigned int fiq_handler_active;
52 static pcpu_fiq_state_t fiq_state[PLATFORM_CORE_COUNT];
53 
54 /*******************************************************************************
55  * Handler for FIQ interrupts
56  ******************************************************************************/
57 static uint64_t tegra_fiq_interrupt_handler(uint32_t id,
58 					  uint32_t flags,
59 					  void *handle,
60 					  void *cookie)
61 {
62 	cpu_context_t *ctx = cm_get_context(NON_SECURE);
63 	el3_state_t *el3state_ctx = get_el3state_ctx(ctx);
64 	int cpu = plat_my_core_pos();
65 	uint32_t irq;
66 
67 	bakery_lock_get(&tegra_fiq_lock);
68 
69 	/*
70 	 * The FIQ was generated when the execution was in the non-secure
71 	 * world. Save the context registers to start with.
72 	 */
73 	cm_el1_sysregs_context_save(NON_SECURE);
74 
75 	/*
76 	 * Save elr_el3 and spsr_el3 from the saved context, and overwrite
77 	 * the context with the NS fiq_handler_addr and SPSR value.
78 	 */
79 	fiq_state[cpu].elr_el3 = read_ctx_reg(el3state_ctx, CTX_ELR_EL3);
80 	fiq_state[cpu].spsr_el3 = read_ctx_reg(el3state_ctx, CTX_SPSR_EL3);
81 
82 	/*
83 	 * Set the new ELR to continue execution in the NS world using the
84 	 * FIQ handler registered earlier.
85 	 */
86 	assert(ns_fiq_handler_addr);
87 	write_ctx_reg(el3state_ctx, CTX_ELR_EL3, ns_fiq_handler_addr);
88 
89 	/*
90 	 * Mark this interrupt as complete to avoid a FIQ storm.
91 	 */
92 	irq = plat_ic_acknowledge_interrupt();
93 	if (irq < 1022)
94 		plat_ic_end_of_interrupt(irq);
95 
96 	bakery_lock_release(&tegra_fiq_lock);
97 
98 	return 0;
99 }
100 
101 /*******************************************************************************
102  * Setup handler for FIQ interrupts
103  ******************************************************************************/
104 void tegra_fiq_handler_setup(void)
105 {
106 	uint64_t flags;
107 	int rc;
108 
109 	/* return if already registered */
110 	if (fiq_handler_active)
111 		return;
112 
113 	/*
114 	 * Register an interrupt handler for FIQ interrupts generated for
115 	 * NS interrupt sources
116 	 */
117 	flags = 0;
118 	set_interrupt_rm_flag(flags, NON_SECURE);
119 	rc = register_interrupt_type_handler(INTR_TYPE_EL3,
120 				tegra_fiq_interrupt_handler,
121 				flags);
122 	if (rc)
123 		panic();
124 
125 	/* handler is now active */
126 	fiq_handler_active = 1;
127 }
128 
129 /*******************************************************************************
130  * Validate and store NS world's entrypoint for FIQ interrupts
131  ******************************************************************************/
132 void tegra_fiq_set_ns_entrypoint(uint64_t entrypoint)
133 {
134 	ns_fiq_handler_addr = entrypoint;
135 }
136 
137 /*******************************************************************************
138  * Handler to return the NS EL1/EL0 CPU context
139  ******************************************************************************/
140 int tegra_fiq_get_intr_context(void)
141 {
142 	cpu_context_t *ctx = cm_get_context(NON_SECURE);
143 	gp_regs_t *gpregs_ctx = get_gpregs_ctx(ctx);
144 	el1_sys_regs_t *el1state_ctx = get_sysregs_ctx(ctx);
145 	int cpu = plat_my_core_pos();
146 	uint64_t val;
147 
148 	/*
149 	 * We store the ELR_EL3, SPSR_EL3, SP_EL0 and SP_EL1 registers so
150 	 * that el3_exit() sends these values back to the NS world.
151 	 */
152 	write_ctx_reg(gpregs_ctx, CTX_GPREG_X0, fiq_state[cpu].elr_el3);
153 	write_ctx_reg(gpregs_ctx, CTX_GPREG_X1, fiq_state[cpu].spsr_el3);
154 
155 	val = read_ctx_reg(gpregs_ctx, CTX_GPREG_SP_EL0);
156 	write_ctx_reg(gpregs_ctx, CTX_GPREG_X2, val);
157 
158 	val = read_ctx_reg(el1state_ctx, CTX_SP_EL1);
159 	write_ctx_reg(gpregs_ctx, CTX_GPREG_X3, val);
160 
161 	return 0;
162 }
163