diff options
| -rw-r--r-- | arch/arm/cpu/armv7/Makefile | 1 | ||||
| -rw-r--r-- | arch/arm/cpu/armv7/virt-v7.c | 122 | ||||
| -rw-r--r-- | arch/arm/include/asm/armv7.h | 3 |
3 files changed, 126 insertions, 0 deletions
diff --git a/arch/arm/cpu/armv7/Makefile b/arch/arm/cpu/armv7/Makefile index 3466c7a..024c28b 100644 --- a/arch/arm/cpu/armv7/Makefile +++ b/arch/arm/cpu/armv7/Makefile @@ -22,6 +22,7 @@ endif ifneq ($(CONFIG_ARMV7_NONSEC),) SOBJS += nonsec_virt.o +COBJS += virt-v7.o endif SRCS := $(START:.o=.S) $(COBJS:.o=.c) diff --git a/arch/arm/cpu/armv7/virt-v7.c b/arch/arm/cpu/armv7/virt-v7.c new file mode 100644 index 0000000..068ac85 --- /dev/null +++ b/arch/arm/cpu/armv7/virt-v7.c @@ -0,0 +1,122 @@ +/* + * (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; +} diff --git a/arch/arm/include/asm/armv7.h b/arch/arm/include/asm/armv7.h index 3dcfc8f..b352d43 100644 --- a/arch/arm/include/asm/armv7.h +++ b/arch/arm/include/asm/armv7.h @@ -77,6 +77,9 @@ void v7_outer_cache_flush_range(u32 start, u32 end); void v7_outer_cache_inval_range(u32 start, u32 end); #ifdef CONFIG_ARMV7_NONSEC + +int armv7_switch_nonsec(void); + /* defined in assembly file */ unsigned int _nonsec_init(void); #endif /* CONFIG_ARMV7_NONSEC */ |