linux/arch/arm/mach-at91/sam_secure.c
Clément Léger 0c9fd82117 ARM: at91: add code to handle secure calls
Since OP-TEE now has a more complete support for sama5d2, add necessary
code to perform SMC calls. The detection of OP-TEE is based on a
specific device-tree node path (/firmware/optee) such has done by some
other SoC. A check is added to avoid doing SMC calls without having
OP-TEE.

Signed-off-by: Clément Léger <clement.leger@bootlin.com>
Signed-off-by: Claudiu Beznea <claudiu.beznea@microchip.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
2022-05-12 14:50:20 +03:00

47 lines
1.0 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2022, Microchip
*/
#include <linux/arm-smccc.h>
#include <linux/of.h>
#include "sam_secure.h"
static bool optee_available;
#define SAM_SIP_SMC_STD_CALL_VAL(func_num) \
ARM_SMCCC_CALL_VAL(ARM_SMCCC_STD_CALL, ARM_SMCCC_SMC_32, \
ARM_SMCCC_OWNER_SIP, (func_num))
struct arm_smccc_res sam_smccc_call(u32 fn, u32 arg0, u32 arg1)
{
struct arm_smccc_res res = {.a0 = -1};
if (WARN_ON(!optee_available))
return res;
arm_smccc_smc(SAM_SIP_SMC_STD_CALL_VAL(fn), arg0, arg1, 0, 0, 0, 0, 0,
&res);
return res;
}
void __init sam_secure_init(void)
{
struct device_node *np;
/*
* We only check that the OP-TEE node is present and available. The
* OP-TEE kernel driver is not needed for the type of interaction made
* with OP-TEE here so the driver's status is not checked.
*/
np = of_find_node_by_path("/firmware/optee");
if (np && of_device_is_available(np))
optee_available = true;
of_node_put(np);
if (optee_available)
pr_info("Running under OP-TEE firmware\n");
}