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