1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2016 Linaro
4  * Jon Medhurst <tixy@linaro.org>
5  *
6  * TC2 specific code for Versatile Express.
7  */
8 
9 #include <asm/armv7.h>
10 #include <asm/io.h>
11 #include <asm/u-boot.h>
12 #include <common.h>
13 #include <linux/libfdt.h>
14 
15 #define SCC_BASE	0x7fff0000
16 
17 bool armv7_boot_nonsec_default(void)
18 {
19 #ifdef CONFIG_ARMV7_BOOT_SEC_DEFAULT
20 	return false;
21 #else
22 	/*
23 	 * The Serial Configuration Controller (SCC) register at address 0x700
24 	 * contains flags for configuring the behaviour of the Boot Monitor
25 	 * (which CPUs execute from reset). Two of these bits are of interest:
26 	 *
27 	 * bit 12 = Use per-cpu mailboxes for power management
28 	 * bit 13 = Power down the non-boot cluster
29 	 *
30 	 * It is only when both of these are false that U-Boot's current
31 	 * implementation of 'nonsec' mode can work as expected because we
32 	 * rely on getting all CPUs to execute _nonsec_init, so let's check that.
33 	 */
34 	return (readl((u32 *)(SCC_BASE + 0x700)) & ((1 << 12) | (1 << 13))) == 0;
35 #endif
36 }
37 
38 #ifdef CONFIG_OF_BOARD_SETUP
39 int ft_board_setup(void *fdt, bd_t *bd)
40 {
41 	int offset, tmp, len;
42 	const struct fdt_property *prop;
43 	const char *cci_compatible = "arm,cci-400-ctrl-if";
44 
45 #ifdef CONFIG_ARMV7_NONSEC
46 	if (!armv7_boot_nonsec())
47 		return 0;
48 #else
49 	return 0;
50 #endif
51 	/* Booting in nonsec mode, disable CCI access */
52 	offset = fdt_path_offset(fdt, "/cpus");
53 	if (offset < 0) {
54 		printf("couldn't find /cpus\n");
55 		return offset;
56 	}
57 
58 	/* delete cci-control-port in each cpu node */
59 	for (tmp = fdt_first_subnode(fdt, offset); tmp >= 0;
60 	     tmp = fdt_next_subnode(fdt, tmp))
61 		fdt_delprop(fdt, tmp, "cci-control-port");
62 
63 	/* disable all ace cci slave ports */
64 	offset = fdt_node_offset_by_prop_value(fdt, offset, "compatible",
65 					       cci_compatible, 20);
66 	while (offset > 0) {
67 		prop = fdt_get_property(fdt, offset, "interface-type",
68 					&len);
69 		if (!prop)
70 			continue;
71 		if (len < 4)
72 			continue;
73 		if (strcmp(prop->data, "ace"))
74 			continue;
75 
76 		fdt_setprop_string(fdt, offset, "status", "disabled");
77 
78 		offset = fdt_node_offset_by_prop_value(fdt, offset, "compatible",
79 						       cci_compatible, 20);
80 	}
81 
82 	return 0;
83 }
84 #endif /* CONFIG_OF_BOARD_SETUP */
85