1/*
2 * Trusted Foundations support for ARM CPUs
3 *
4 * Copyright (c) 2013, NVIDIA Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
14 * more details.
15 */
16
17#include <linux/kernel.h>
18#include <linux/init.h>
19#include <linux/of.h>
20#include <asm/firmware.h>
21#include <asm/trusted_foundations.h>
22
23#define TF_SET_CPU_BOOT_ADDR_SMC 0xfffff200
24
25#define TF_CPU_PM		0xfffffffc
26#define TF_CPU_PM_S3		0xffffffe3
27#define TF_CPU_PM_S2		0xffffffe6
28#define TF_CPU_PM_S2_NO_MC_CLK	0xffffffe5
29#define TF_CPU_PM_S1		0xffffffe4
30#define TF_CPU_PM_S1_NOFLUSH_L2	0xffffffe7
31
32static unsigned long cpu_boot_addr;
33
34static void __naked tf_generic_smc(u32 type, u32 arg1, u32 arg2)
35{
36	asm volatile(
37		".arch_extension	sec\n\t"
38		"stmfd	sp!, {r4 - r11, lr}\n\t"
39		__asmeq("%0", "r0")
40		__asmeq("%1", "r1")
41		__asmeq("%2", "r2")
42		"mov	r3, #0\n\t"
43		"mov	r4, #0\n\t"
44		"smc	#0\n\t"
45		"ldmfd	sp!, {r4 - r11, pc}"
46		:
47		: "r" (type), "r" (arg1), "r" (arg2)
48		: "memory");
49}
50
51static int tf_set_cpu_boot_addr(int cpu, unsigned long boot_addr)
52{
53	cpu_boot_addr = boot_addr;
54	tf_generic_smc(TF_SET_CPU_BOOT_ADDR_SMC, cpu_boot_addr, 0);
55
56	return 0;
57}
58
59static int tf_prepare_idle(void)
60{
61	tf_generic_smc(TF_CPU_PM, TF_CPU_PM_S1_NOFLUSH_L2, cpu_boot_addr);
62
63	return 0;
64}
65
66static const struct firmware_ops trusted_foundations_ops = {
67	.set_cpu_boot_addr = tf_set_cpu_boot_addr,
68	.prepare_idle = tf_prepare_idle,
69};
70
71void register_trusted_foundations(struct trusted_foundations_platform_data *pd)
72{
73	/*
74	 * we are not using version information for now since currently
75	 * supported SMCs are compatible with all TF releases
76	 */
77	register_firmware_ops(&trusted_foundations_ops);
78}
79
80void of_register_trusted_foundations(void)
81{
82	struct device_node *node;
83	struct trusted_foundations_platform_data pdata;
84	int err;
85
86	node = of_find_compatible_node(NULL, NULL, "tlm,trusted-foundations");
87	if (!node)
88		return;
89
90	err = of_property_read_u32(node, "tlm,version-major",
91				   &pdata.version_major);
92	if (err != 0)
93		panic("Trusted Foundation: missing version-major property\n");
94	err = of_property_read_u32(node, "tlm,version-minor",
95				   &pdata.version_minor);
96	if (err != 0)
97		panic("Trusted Foundation: missing version-minor property\n");
98	register_trusted_foundations(&pdata);
99}
100