1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
|
/*
* (C) Copyright 2013
* Andre Przywara, Linaro
*
* Routines to transition ARMv7 processors from secure into non-secure state
* needed to enable ARMv7 virtualization for current hypervisors
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <common.h>
#include <asm/armv7.h>
#include <asm/gic.h>
#include <asm/io.h>
unsigned long gic_dist_addr;
static unsigned int read_id_pfr1(void)
{
unsigned int reg;
asm("mrc p15, 0, %0, c0, c1, 1\n" : "=r"(reg));
return reg;
}
static unsigned long get_gicd_base_address(void)
{
#ifdef CONFIG_ARM_GIC_BASE_ADDRESS
return CONFIG_ARM_GIC_BASE_ADDRESS + GIC_DIST_OFFSET;
#else
unsigned midr;
unsigned periphbase;
/* check whether we are an Cortex-A15 or A7.
* The actual HYP switch should work with all CPUs supporting
* the virtualization extension, but we need the GIC address,
* which we know only for sure for those two CPUs.
*/
asm("mrc p15, 0, %0, c0, c0, 0\n" : "=r"(midr));
switch (midr & MIDR_PRIMARY_PART_MASK) {
case MIDR_CORTEX_A9_R0P1:
case MIDR_CORTEX_A15_R0P0:
case MIDR_CORTEX_A7_R0P0:
break;
default:
printf("nonsec: could not determine GIC address.\n");
return -1;
}
/* get the GIC base address from the CBAR register */
asm("mrc p15, 4, %0, c15, c0, 0\n" : "=r" (periphbase));
/* the PERIPHBASE can be mapped above 4 GB (lower 8 bits used to
* encode this). Bail out here since we cannot access this without
* enabling paging.
*/
if ((periphbase & 0xff) != 0) {
printf("nonsec: PERIPHBASE is above 4 GB, no access.\n");
return -1;
}
return (periphbase & CBAR_MASK) + GIC_DIST_OFFSET;
#endif
}
int armv7_switch_nonsec(void)
{
unsigned int reg;
unsigned itlinesnr, i;
/* check whether the CPU supports the security extensions */
reg = read_id_pfr1();
if ((reg & 0xF0) == 0) {
printf("nonsec: Security extensions not implemented.\n");
return -1;
}
/* the SCR register will be set directly in the monitor mode handler,
* according to the spec one should not tinker with it in secure state
* in SVC mode. Do not try to read it once in non-secure state,
* any access to it will trap.
*/
gic_dist_addr = get_gicd_base_address();
if (gic_dist_addr == -1)
return -1;
/* enable the GIC distributor */
writel(readl(gic_dist_addr + GICD_CTLR) | 0x03,
gic_dist_addr + GICD_CTLR);
/* TYPER[4:0] contains an encoded number of available interrupts */
itlinesnr = readl(gic_dist_addr + GICD_TYPER) & 0x1f;
/* set all bits in the GIC group registers to one to allow access
* from non-secure state. The first 32 interrupts are private per
* CPU and will be set later when enabling the GIC for each core
*/
for (i = 1; i <= itlinesnr; i++)
writel((unsigned)-1, gic_dist_addr + GICD_IGROUPRn + 4 * i);
/* call the non-sec switching code on this CPU */
_nonsec_init();
return 0;
}
|
