uboot/u-boot-stm32mp-2020.01/arch/arm/cpu/armv7/virt-v7.c

145 lines
3.7 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2013
* Andre Przywara, Linaro <andre.przywara@linaro.org>
*
* Routines to transition ARMv7 processors from secure into non-secure state
* and from non-secure SVC into HYP mode
* needed to enable ARMv7 virtualization for current hypervisors
*/
#include <common.h>
#include <cpu_func.h>
#include <asm/armv7.h>
#include <asm/gic.h>
#include <asm/io.h>
#include <asm/secure.h>
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 periphbase;
/* 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
}
/* Define a specific version of this function to enable any available
* hardware protections for the reserved region */
void __weak protect_secure_section(void) {}
static void relocate_secure_section(void)
{
#ifdef CONFIG_ARMV7_SECURE_BASE
size_t sz = __secure_end - __secure_start;
unsigned long szflush = ALIGN(sz + 1, CONFIG_SYS_CACHELINE_SIZE);
memcpy((void *)CONFIG_ARMV7_SECURE_BASE, __secure_start, sz);
flush_dcache_range(CONFIG_ARMV7_SECURE_BASE,
CONFIG_ARMV7_SECURE_BASE + szflush);
protect_secure_section();
invalidate_icache_all();
#endif
}
static void kick_secondary_cpus_gic(unsigned long gicdaddr)
{
/* kick all CPUs (except this one) by writing to GICD_SGIR */
writel(1U << 24, gicdaddr + GICD_SGIR);
}
void __weak smp_kick_all_cpus(void)
{
unsigned long gic_dist_addr;
gic_dist_addr = get_gicd_base_address();
if (gic_dist_addr == -1)
return;
kick_secondary_cpus_gic(gic_dist_addr);
}
__weak void psci_board_init(void)
{
}
int armv7_init_nonsec(void)
{
unsigned int reg;
unsigned itlinesnr, i;
unsigned long gic_dist_addr;
/* 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);
psci_board_init();
/*
* Relocate secure section before any cpu runs in secure ram.
* smp_kick_all_cpus may enable other cores and runs into secure
* ram, so need to relocate secure section before enabling other
* cores.
*/
relocate_secure_section();
#ifndef CONFIG_ARMV7_PSCI
smp_set_core_boot_addr((unsigned long)secure_ram_addr(_smp_pen), -1);
smp_kick_all_cpus();
#endif
/* call the non-sec switching code on this CPU also */
secure_ram_addr(_nonsec_init)();
return 0;
}