common/feat_detect.c - filogic/atf - Gitiles

 /*
  * Copyright (c) 2022-2023, Arm Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */

 #include <arch_features.h>
 #include <common/debug.h>
 #include <common/feat_detect.h>

 static bool tainted;

 /*******************************************************************************
  * This section lists the wrapper modules for each feature to evaluate the
  * feature states (FEAT_STATE_ALWAYS and FEAT_STATE_CHECK) and perform
  * necessary action as below:
  *
  * It verifies whether the FEAT_XXX (eg: FEAT_SB) is supported by the PE or not.
  * Without this check an exception would occur during context save/restore
  * routines, if the feature is enabled but not supported by PE.
  ******************************************************************************/

 #define feat_detect_panic(a, b)		((a) ? (void)0 : feature_panic(b))

 /*******************************************************************************
  * Function : feature_panic
  * Customised panic function with error logging mechanism to list the feature
  * not supported by the PE.
  ******************************************************************************/
 static inline void feature_panic(char *feat_name)
 {
 	ERROR("FEAT_%s not supported by the PE\n", feat_name);
 	panic();
 }

 /*******************************************************************************
  * Function : check_feature
  * Check for a valid combination of build time flags (ENABLE_FEAT_xxx) and
  * feature availability on the hardware. <min> is the smallest feature
  * ID field value that is required for that feature.
  * Triggers a panic later if a feature is forcefully enabled, but not
  * available on the PE. Also will panic if the hardware feature ID field
  * is larger than the maximum known and supported number, specified by <max>.
  *
  * We force inlining here to let the compiler optimise away the whole check
  * if the feature is disabled at build time (FEAT_STATE_DISABLED).
  ******************************************************************************/
 static inline void __attribute((__always_inline__))
 check_feature(int state, unsigned long field, const char *feat_name,
 	      unsigned int min, unsigned int max)
 {
 	if (state == FEAT_STATE_ALWAYS && field < min) {
 		ERROR("FEAT_%s not supported by the PE\n", feat_name);
 		tainted = true;
 	}
 	if (state >= FEAT_STATE_ALWAYS && field > max) {
 		ERROR("FEAT_%s is version %ld, but is only known up to version %d\n",
 		      feat_name, field, max);
 		tainted = true;
 	}
 }

 /************************************************
  * Feature : FEAT_PAUTH (Pointer Authentication)
  ***********************************************/
 static void read_feat_pauth(void)
 {
 #if (ENABLE_PAUTH == FEAT_STATE_ALWAYS) || (CTX_INCLUDE_PAUTH_REGS == FEAT_STATE_ALWAYS)
 	feat_detect_panic(is_armv8_3_pauth_present(), "PAUTH");
 #endif
 }

 /************************************************
  * Feature : FEAT_MTE (Memory Tagging Extension)
  ***********************************************/
 static void read_feat_mte(void)
 {
 #if (CTX_INCLUDE_MTE_REGS == FEAT_STATE_ALWAYS)
 	unsigned int mte = get_armv8_5_mte_support();

 	feat_detect_panic((mte != MTE_UNIMPLEMENTED), "MTE");
 #endif
 }

 /****************************************************
  * Feature : FEAT_BTI (Branch Target Identification)
  ***************************************************/
 static void read_feat_bti(void)
 {
 #if (ENABLE_BTI == FEAT_STATE_ALWAYS)
 	feat_detect_panic(is_armv8_5_bti_present(), "BTI");
 #endif
 }

 /**************************************************
  * Feature : FEAT_RME (Realm Management Extension)
  *************************************************/
 static void read_feat_rme(void)
 {
 #if (ENABLE_RME == FEAT_STATE_ALWAYS)
 	feat_detect_panic((get_armv9_2_feat_rme_support() !=
 			ID_AA64PFR0_FEAT_RME_NOT_SUPPORTED), "RME");
 #endif
 }

 /******************************************************************
  * Feature : FEAT_RNG_TRAP (Trapping support for RNDR/RNDRRS)
  *****************************************************************/
 static void read_feat_rng_trap(void)
 {
 #if (ENABLE_FEAT_RNG_TRAP == FEAT_STATE_ALWAYS)
 	feat_detect_panic(is_feat_rng_trap_present(), "RNG_TRAP");
 #endif
 }

 /***********************************************************************************
  * TF-A supports many Arm architectural features starting from arch version
  * (8.0 till 8.7+). These features are mostly enabled through build flags. This
  * mechanism helps in validating these build flags in the early boot phase
  * either in BL1 or BL31 depending on the platform and assists in identifying
  * and notifying the features which are enabled but not supported by the PE.
  *
  * It reads all the enabled features ID-registers and ensures the features
  * are supported by the PE.
  * In case if they aren't it stops booting at an early phase and logs the error
  * messages, notifying the platforms about the features that are not supported.
  *
  * Further the procedure is implemented with a tri-state approach for each feature:
  * ENABLE_FEAT_xxx = 0 : The feature is disabled statically at compile time
  * ENABLE_FEAT_xxx = 1 : The feature is enabled and must be present in hardware.
  *                       There will be panic if feature is not present at cold boot.
  * ENABLE_FEAT_xxx = 2 : The feature is enabled but dynamically enabled at runtime
  *                       depending on hardware capability.
  *
  * For better readability, state values are defined with macros, namely:
  * { FEAT_STATE_DISABLED, FEAT_STATE_ALWAYS, FEAT_STATE_CHECK }, taking values
  * { 0, 1, 2 }, respectively, as their naming.
  **********************************************************************************/
 void detect_arch_features(void)
 {
 	tainted = false;

 	/* v8.0 features */
 	check_feature(ENABLE_FEAT_SB, read_feat_sb_id_field(), "SB", 1, 1);
 	check_feature(ENABLE_FEAT_CSV2_2, read_feat_csv2_id_field(),
 		      "CSV2_2", 2, 3);

 	/* v8.1 features */
 	check_feature(ENABLE_FEAT_PAN, read_feat_pan_id_field(), "PAN", 1, 3);
 	check_feature(ENABLE_FEAT_VHE, read_feat_vhe_id_field(), "VHE", 1, 1);

 	/* v8.2 features */
 	check_feature(ENABLE_SVE_FOR_NS, read_feat_sve_id_field(),
 		      "SVE", 1, 1);
 	check_feature(ENABLE_FEAT_RAS, read_feat_ras_id_field(), "RAS", 1, 2);

 	/* v8.3 features */
 	read_feat_pauth();

 	/* v8.4 features */
 	check_feature(ENABLE_FEAT_DIT, read_feat_dit_id_field(), "DIT", 1, 1);
 	check_feature(ENABLE_FEAT_AMU, read_feat_amu_id_field(),
 		      "AMUv1", 1, 2);
 	check_feature(ENABLE_MPAM_FOR_LOWER_ELS, read_feat_mpam_version(),
 		      "MPAM", 1, 17);
 	check_feature(CTX_INCLUDE_NEVE_REGS, read_feat_nv_id_field(),
 		      "NV2", 2, 2);
 	check_feature(ENABLE_FEAT_SEL2, read_feat_sel2_id_field(),
 		      "SEL2", 1, 1);
 	check_feature(ENABLE_TRF_FOR_NS, read_feat_trf_id_field(),
 		      "TRF", 1, 1);

 	/* v8.5 features */
 	read_feat_mte();
 	check_feature(ENABLE_FEAT_RNG, read_feat_rng_id_field(), "RNG", 1, 1);
 	read_feat_bti();
 	read_feat_rng_trap();

 	/* v8.6 features */
 	check_feature(ENABLE_FEAT_AMUv1p1, read_feat_amu_id_field(),
 		      "AMUv1p1", 2, 2);
 	check_feature(ENABLE_FEAT_FGT, read_feat_fgt_id_field(), "FGT", 1, 1);
 	check_feature(ENABLE_FEAT_ECV, read_feat_ecv_id_field(), "ECV", 1, 2);
 	check_feature(ENABLE_FEAT_TWED, read_feat_twed_id_field(),
 		      "TWED", 1, 1);

 	/* v8.7 features */
 	check_feature(ENABLE_FEAT_HCX, read_feat_hcx_id_field(), "HCX", 1, 1);

 	/* v8.9 features */
 	check_feature(ENABLE_FEAT_TCR2, read_feat_tcrx_id_field(),
 		      "TCR2", 1, 1);
 	check_feature(ENABLE_FEAT_S2PIE, read_feat_s2pie_id_field(),
 		      "S2PIE", 1, 1);
 	check_feature(ENABLE_FEAT_S1PIE, read_feat_s1pie_id_field(),
 		      "S1PIE", 1, 1);
 	check_feature(ENABLE_FEAT_S2POE, read_feat_s2poe_id_field(),
 		      "S2POE", 1, 1);
 	check_feature(ENABLE_FEAT_S1POE, read_feat_s1poe_id_field(),
 		      "S1POE", 1, 1);

 	/* v9.0 features */
 	check_feature(ENABLE_BRBE_FOR_NS, read_feat_brbe_id_field(),
 		      "BRBE", 1, 2);
 	check_feature(ENABLE_TRBE_FOR_NS, read_feat_trbe_id_field(),
 		      "TRBE", 1, 1);

 	/* v9.2 features */
 	check_feature(ENABLE_SME_FOR_NS, read_feat_sme_id_field(),
 		      "SME", 1, 2);
 	check_feature(ENABLE_SME2_FOR_NS, read_feat_sme_id_field(),
 		      "SME2", 2, 2);

 	/* v9.4 features */
 	check_feature(ENABLE_FEAT_GCS, read_feat_gcs_id_field(), "GCS", 1, 1);

 	read_feat_rme();

 	if (tainted) {
 		panic();
 	}
 }
	/*
	* Copyright (c) 2022-2023, Arm Limited and Contributors. All rights reserved.
	*
	* SPDX-License-Identifier: BSD-3-Clause
	*/

	#include <arch_features.h>
	#include <common/debug.h>
	#include <common/feat_detect.h>

	static bool tainted;

	/*******************************************************************************
	* This section lists the wrapper modules for each feature to evaluate the
	* feature states (FEAT_STATE_ALWAYS and FEAT_STATE_CHECK) and perform
	* necessary action as below:
	*
	* It verifies whether the FEAT_XXX (eg: FEAT_SB) is supported by the PE or not.
	* Without this check an exception would occur during context save/restore
	* routines, if the feature is enabled but not supported by PE.
	******************************************************************************/

	#define feat_detect_panic(a, b) ((a) ? (void)0 : feature_panic(b))

	/*******************************************************************************
	* Function : feature_panic
	* Customised panic function with error logging mechanism to list the feature
	* not supported by the PE.
	******************************************************************************/
	static inline void feature_panic(char *feat_name)
	{
	ERROR("FEAT_%s not supported by the PE\n", feat_name);
	panic();
	}

	/*******************************************************************************
	* Function : check_feature
	* Check for a valid combination of build time flags (ENABLE_FEAT_xxx) and
	* feature availability on the hardware. <min> is the smallest feature
	* ID field value that is required for that feature.
	* Triggers a panic later if a feature is forcefully enabled, but not
	* available on the PE. Also will panic if the hardware feature ID field
	* is larger than the maximum known and supported number, specified by <max>.
	*
	* We force inlining here to let the compiler optimise away the whole check
	* if the feature is disabled at build time (FEAT_STATE_DISABLED).
	******************************************************************************/
	static inline void __attribute((__always_inline__))
	check_feature(int state, unsigned long field, const char *feat_name,
	unsigned int min, unsigned int max)
	{
	if (state == FEAT_STATE_ALWAYS && field < min) {
	ERROR("FEAT_%s not supported by the PE\n", feat_name);
	tainted = true;
	}
	if (state >= FEAT_STATE_ALWAYS && field > max) {
	ERROR("FEAT_%s is version %ld, but is only known up to version %d\n",
	feat_name, field, max);
	tainted = true;
	}
	}

	/************************************************
	* Feature : FEAT_PAUTH (Pointer Authentication)
	***********************************************/
	static void read_feat_pauth(void)
	{
	#if (ENABLE_PAUTH == FEAT_STATE_ALWAYS) \|\| (CTX_INCLUDE_PAUTH_REGS == FEAT_STATE_ALWAYS)
	feat_detect_panic(is_armv8_3_pauth_present(), "PAUTH");
	#endif
	}

	/************************************************
	* Feature : FEAT_MTE (Memory Tagging Extension)
	***********************************************/
	static void read_feat_mte(void)
	{
	#if (CTX_INCLUDE_MTE_REGS == FEAT_STATE_ALWAYS)
	unsigned int mte = get_armv8_5_mte_support();

	feat_detect_panic((mte != MTE_UNIMPLEMENTED), "MTE");
	#endif
	}

	/****************************************************
	* Feature : FEAT_BTI (Branch Target Identification)
	***************************************************/
	static void read_feat_bti(void)
	{
	#if (ENABLE_BTI == FEAT_STATE_ALWAYS)
	feat_detect_panic(is_armv8_5_bti_present(), "BTI");
	#endif
	}

	/**************************************************
	* Feature : FEAT_RME (Realm Management Extension)
	*************************************************/
	static void read_feat_rme(void)
	{
	#if (ENABLE_RME == FEAT_STATE_ALWAYS)
	feat_detect_panic((get_armv9_2_feat_rme_support() !=
	ID_AA64PFR0_FEAT_RME_NOT_SUPPORTED), "RME");
	#endif
	}

	/******************************************************************
	* Feature : FEAT_RNG_TRAP (Trapping support for RNDR/RNDRRS)
	*****************************************************************/
	static void read_feat_rng_trap(void)
	{
	#if (ENABLE_FEAT_RNG_TRAP == FEAT_STATE_ALWAYS)
	feat_detect_panic(is_feat_rng_trap_present(), "RNG_TRAP");
	#endif
	}

	/***********************************************************************************
	* TF-A supports many Arm architectural features starting from arch version
	* (8.0 till 8.7+). These features are mostly enabled through build flags. This
	* mechanism helps in validating these build flags in the early boot phase
	* either in BL1 or BL31 depending on the platform and assists in identifying
	* and notifying the features which are enabled but not supported by the PE.
	*
	* It reads all the enabled features ID-registers and ensures the features
	* are supported by the PE.
	* In case if they aren't it stops booting at an early phase and logs the error
	* messages, notifying the platforms about the features that are not supported.
	*
	* Further the procedure is implemented with a tri-state approach for each feature:
	* ENABLE_FEAT_xxx = 0 : The feature is disabled statically at compile time
	* ENABLE_FEAT_xxx = 1 : The feature is enabled and must be present in hardware.
	* There will be panic if feature is not present at cold boot.
	* ENABLE_FEAT_xxx = 2 : The feature is enabled but dynamically enabled at runtime
	* depending on hardware capability.
	*
	* For better readability, state values are defined with macros, namely:
	* { FEAT_STATE_DISABLED, FEAT_STATE_ALWAYS, FEAT_STATE_CHECK }, taking values
	* { 0, 1, 2 }, respectively, as their naming.
	**********************************************************************************/
	void detect_arch_features(void)
	{
	tainted = false;

	/* v8.0 features */
	check_feature(ENABLE_FEAT_SB, read_feat_sb_id_field(), "SB", 1, 1);
	check_feature(ENABLE_FEAT_CSV2_2, read_feat_csv2_id_field(),
	"CSV2_2", 2, 3);

	/* v8.1 features */
	check_feature(ENABLE_FEAT_PAN, read_feat_pan_id_field(), "PAN", 1, 3);
	check_feature(ENABLE_FEAT_VHE, read_feat_vhe_id_field(), "VHE", 1, 1);

	/* v8.2 features */
	check_feature(ENABLE_SVE_FOR_NS, read_feat_sve_id_field(),
	"SVE", 1, 1);
	check_feature(ENABLE_FEAT_RAS, read_feat_ras_id_field(), "RAS", 1, 2);

	/* v8.3 features */
	read_feat_pauth();

	/* v8.4 features */
	check_feature(ENABLE_FEAT_DIT, read_feat_dit_id_field(), "DIT", 1, 1);
	check_feature(ENABLE_FEAT_AMU, read_feat_amu_id_field(),
	"AMUv1", 1, 2);
	check_feature(ENABLE_MPAM_FOR_LOWER_ELS, read_feat_mpam_version(),
	"MPAM", 1, 17);
	check_feature(CTX_INCLUDE_NEVE_REGS, read_feat_nv_id_field(),
	"NV2", 2, 2);
	check_feature(ENABLE_FEAT_SEL2, read_feat_sel2_id_field(),
	"SEL2", 1, 1);
	check_feature(ENABLE_TRF_FOR_NS, read_feat_trf_id_field(),
	"TRF", 1, 1);

	/* v8.5 features */
	read_feat_mte();
	check_feature(ENABLE_FEAT_RNG, read_feat_rng_id_field(), "RNG", 1, 1);
	read_feat_bti();
	read_feat_rng_trap();

	/* v8.6 features */
	check_feature(ENABLE_FEAT_AMUv1p1, read_feat_amu_id_field(),
	"AMUv1p1", 2, 2);
	check_feature(ENABLE_FEAT_FGT, read_feat_fgt_id_field(), "FGT", 1, 1);
	check_feature(ENABLE_FEAT_ECV, read_feat_ecv_id_field(), "ECV", 1, 2);
	check_feature(ENABLE_FEAT_TWED, read_feat_twed_id_field(),
	"TWED", 1, 1);

	/* v8.7 features */
	check_feature(ENABLE_FEAT_HCX, read_feat_hcx_id_field(), "HCX", 1, 1);

	/* v8.9 features */
	check_feature(ENABLE_FEAT_TCR2, read_feat_tcrx_id_field(),
	"TCR2", 1, 1);
	check_feature(ENABLE_FEAT_S2PIE, read_feat_s2pie_id_field(),
	"S2PIE", 1, 1);
	check_feature(ENABLE_FEAT_S1PIE, read_feat_s1pie_id_field(),
	"S1PIE", 1, 1);
	check_feature(ENABLE_FEAT_S2POE, read_feat_s2poe_id_field(),
	"S2POE", 1, 1);
	check_feature(ENABLE_FEAT_S1POE, read_feat_s1poe_id_field(),
	"S1POE", 1, 1);

	/* v9.0 features */
	check_feature(ENABLE_BRBE_FOR_NS, read_feat_brbe_id_field(),
	"BRBE", 1, 2);
	check_feature(ENABLE_TRBE_FOR_NS, read_feat_trbe_id_field(),
	"TRBE", 1, 1);

	/* v9.2 features */
	check_feature(ENABLE_SME_FOR_NS, read_feat_sme_id_field(),
	"SME", 1, 2);
	check_feature(ENABLE_SME2_FOR_NS, read_feat_sme_id_field(),
	"SME2", 2, 2);

	/* v9.4 features */
	check_feature(ENABLE_FEAT_GCS, read_feat_gcs_id_field(), "GCS", 1, 1);

	read_feat_rme();

	if (tainted) {
	panic();
	}
	}