xref: /rk3399_ARM-atf/bl32/tsp/tsp_interrupt.c (revision 404dba53ef9be643f80babdd4ab81501bdbaba16)
1 /*
2  * Copyright (c) 2014-2015, 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 <debug.h>
34 #include <gic_v2.h>
35 #include <platform.h>
36 #include <platform_def.h>
37 #include <tsp.h>
38 #include "tsp_private.h"
39 
40 /*******************************************************************************
41  * This function updates the TSP statistics for FIQs handled synchronously i.e
42  * the ones that have been handed over by the TSPD. It also keeps count of the
43  * number of times control was passed back to the TSPD after handling an FIQ.
44  * In the future it will be possible that the TSPD hands over an FIQ to the TSP
45  * but does not expect it to return execution. This statistic will be useful to
46  * distinguish between these two models of synchronous FIQ handling.
47  * The 'elr_el3' parameter contains the address of the instruction in normal
48  * world where this FIQ was generated.
49  ******************************************************************************/
50 void tsp_update_sync_fiq_stats(uint32_t type, uint64_t elr_el3)
51 {
52 	uint32_t linear_id = plat_my_core_pos();
53 
54 	tsp_stats[linear_id].sync_fiq_count++;
55 	if (type == TSP_HANDLE_FIQ_AND_RETURN)
56 		tsp_stats[linear_id].sync_fiq_ret_count++;
57 
58 #if LOG_LEVEL >= LOG_LEVEL_VERBOSE
59 	spin_lock(&console_lock);
60 	VERBOSE("TSP: cpu 0x%lx sync fiq request from 0x%lx\n",
61 		read_mpidr(), elr_el3);
62 	VERBOSE("TSP: cpu 0x%lx: %d sync fiq requests, %d sync fiq returns\n",
63 		read_mpidr(),
64 		tsp_stats[linear_id].sync_fiq_count,
65 		tsp_stats[linear_id].sync_fiq_ret_count);
66 	spin_unlock(&console_lock);
67 #endif
68 }
69 
70 /******************************************************************************
71  * This function is invoked when a non S-EL1 interrupt is received and causes
72  * the preemption of TSP. This function returns TSP_PREEMPTED and results
73  * in the control being handed over to EL3 for handling the interrupt.
74  *****************************************************************************/
75 int32_t tsp_handle_preemption(void)
76 {
77 	uint32_t linear_id = plat_my_core_pos();
78 
79 	tsp_stats[linear_id].preempt_intr_count++;
80 #if LOG_LEVEL >= LOG_LEVEL_VERBOSE
81 	spin_lock(&console_lock);
82 	VERBOSE("TSP: cpu 0x%lx: %d preempt interrupt requests\n",
83 		read_mpidr(), tsp_stats[linear_id].preempt_intr_count);
84 	spin_unlock(&console_lock);
85 #endif
86 	return TSP_PREEMPTED;
87 }
88 
89 /*******************************************************************************
90  * TSP FIQ handler called as a part of both synchronous and asynchronous
91  * handling of FIQ interrupts. It returns 0 upon successfully handling a S-EL1
92  * FIQ and treats all other FIQs as EL3 interrupts. It assumes that the GIC
93  * architecture version in v2.0 and the secure physical timer interrupt is the
94  * only S-EL1 interrupt that it needs to handle.
95  ******************************************************************************/
96 int32_t tsp_fiq_handler(void)
97 {
98 	uint32_t linear_id = plat_my_core_pos(), id;
99 
100 	/*
101 	 * Get the highest priority pending interrupt id and see if it is the
102 	 * secure physical generic timer interrupt in which case, handle it.
103 	 * Otherwise throw this interrupt at the EL3 firmware.
104 	 *
105 	 * There is a small time window between reading the highest priority
106 	 * pending interrupt and acknowledging it during which another
107 	 * interrupt of higher priority could become the highest pending
108 	 * interrupt. This is not expected to happen currently for TSP.
109 	 */
110 	id = plat_ic_get_pending_interrupt_id();
111 
112 	/* TSP can only handle the secure physical timer interrupt */
113 	if (id != TSP_IRQ_SEC_PHY_TIMER)
114 		return tsp_handle_preemption();
115 
116 	/*
117 	 * Acknowledge and handle the secure timer interrupt. Also sanity check
118 	 * if it has been preempted by another interrupt through an assertion.
119 	 */
120 	id = plat_ic_acknowledge_interrupt();
121 	assert(id == TSP_IRQ_SEC_PHY_TIMER);
122 	tsp_generic_timer_handler();
123 	plat_ic_end_of_interrupt(id);
124 
125 	/* Update the statistics and print some messages */
126 	tsp_stats[linear_id].fiq_count++;
127 #if LOG_LEVEL >= LOG_LEVEL_VERBOSE
128 	spin_lock(&console_lock);
129 	VERBOSE("TSP: cpu 0x%lx handled fiq %d\n",
130 	       read_mpidr(), id);
131 	VERBOSE("TSP: cpu 0x%lx: %d fiq requests\n",
132 	     read_mpidr(), tsp_stats[linear_id].fiq_count);
133 	spin_unlock(&console_lock);
134 #endif
135 	return 0;
136 }
137