Dmitry Osipenko 2af6597ac3 ARM: tegra: Don't apply CPU erratas in insecure mode
CPU isn't allowed to touch secure registers while running under secure
monitor. Hence skip applying of CPU erratas in the reset handler if
Trusted Foundations firmware presents.

Partially based on work done by Michał Mirosław [1].

[1] https://www.spinics.net/lists/arm-kernel/msg594768.html

Tested-by: Robert Yang <decatf@gmail.com>
Tested-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
2019-04-09 16:36:24 +02:00

112 lines
2.8 KiB
C

/*
* arch/arm/mach-tegra/reset.c
*
* Copyright (C) 2011,2012 NVIDIA Corporation.
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* 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.
*
*/
#include <linux/bitops.h>
#include <linux/cpumask.h>
#include <linux/init.h>
#include <linux/io.h>
#include <soc/tegra/fuse.h>
#include <asm/cacheflush.h>
#include <asm/firmware.h>
#include <asm/hardware/cache-l2x0.h>
#include <asm/trusted_foundations.h>
#include "iomap.h"
#include "irammap.h"
#include "reset.h"
#include "sleep.h"
#define TEGRA_IRAM_RESET_BASE (TEGRA_IRAM_BASE + \
TEGRA_IRAM_RESET_HANDLER_OFFSET)
static bool is_enabled;
static void __init tegra_cpu_reset_handler_set(const u32 reset_address)
{
void __iomem *evp_cpu_reset =
IO_ADDRESS(TEGRA_EXCEPTION_VECTORS_BASE + 0x100);
void __iomem *sb_ctrl = IO_ADDRESS(TEGRA_SB_BASE);
u32 reg;
/*
* NOTE: This must be the one and only write to the EVP CPU reset
* vector in the entire system.
*/
writel(reset_address, evp_cpu_reset);
wmb();
reg = readl(evp_cpu_reset);
/*
* Prevent further modifications to the physical reset vector.
* NOTE: Has no effect on chips prior to Tegra30.
*/
reg = readl(sb_ctrl);
reg |= 2;
writel(reg, sb_ctrl);
wmb();
}
static void __init tegra_cpu_reset_handler_enable(void)
{
void __iomem *iram_base = IO_ADDRESS(TEGRA_IRAM_RESET_BASE);
const u32 reset_address = TEGRA_IRAM_RESET_BASE +
tegra_cpu_reset_handler_offset;
int err;
BUG_ON(is_enabled);
BUG_ON(tegra_cpu_reset_handler_size > TEGRA_IRAM_RESET_HANDLER_SIZE);
memcpy(iram_base, (void *)__tegra_cpu_reset_handler_start,
tegra_cpu_reset_handler_size);
err = call_firmware_op(set_cpu_boot_addr, 0, reset_address);
switch (err) {
case -ENOSYS:
tegra_cpu_reset_handler_set(reset_address);
/* pass-through */
case 0:
is_enabled = true;
break;
default:
pr_crit("Cannot set CPU reset handler: %d\n", err);
BUG();
}
}
void __init tegra_cpu_reset_handler_init(void)
{
__tegra_cpu_reset_handler_data[TEGRA_RESET_TF_PRESENT] =
trusted_foundations_registered();
#ifdef CONFIG_SMP
__tegra_cpu_reset_handler_data[TEGRA_RESET_MASK_PRESENT] =
*((u32 *)cpu_possible_mask);
__tegra_cpu_reset_handler_data[TEGRA_RESET_STARTUP_SECONDARY] =
__pa_symbol((void *)secondary_startup);
#endif
#ifdef CONFIG_PM_SLEEP
__tegra_cpu_reset_handler_data[TEGRA_RESET_STARTUP_LP1] =
TEGRA_IRAM_LPx_RESUME_AREA;
__tegra_cpu_reset_handler_data[TEGRA_RESET_STARTUP_LP2] =
__pa_symbol((void *)tegra_resume);
#endif
tegra_cpu_reset_handler_enable();
}