Remove MBEDTLS_SHA256_ALT

Signed-off-by: Thomas Daubney <thomas.daubney@arm.com>
diff --git a/include/mbedtls/check_config.h b/include/mbedtls/check_config.h
index 178bd39..9f1ca2b 100644
--- a/include/mbedtls/check_config.h
+++ b/include/mbedtls/check_config.h
@@ -750,8 +750,8 @@
 #if !defined(MBEDTLS_SHA256_C)
 #error "MBEDTLS_SHA256_USE_ARMV8_A_CRYPTO_* defined without MBEDTLS_SHA256_C"
 #endif
-#if defined(MBEDTLS_SHA256_ALT) || defined(MBEDTLS_SHA256_PROCESS_ALT)
-#error "MBEDTLS_SHA256_*ALT can't be used with MBEDTLS_SHA256_USE_ARMV8_A_CRYPTO_*"
+#if defined(MBEDTLS_SHA256_PROCESS_ALT)
+#error "MBEDTLS_SHA256_PROCESS_ALT can't be used with MBEDTLS_SHA256_USE_ARMV8_A_CRYPTO_*"
 #endif
 
 #endif
diff --git a/include/mbedtls/mbedtls_config.h b/include/mbedtls/mbedtls_config.h
index 007a22d..5b972a9 100644
--- a/include/mbedtls/mbedtls_config.h
+++ b/include/mbedtls/mbedtls_config.h
@@ -352,7 +352,6 @@
 
 //#define MBEDTLS_CMAC_ALT
 //#define MBEDTLS_MD5_ALT
-//#define MBEDTLS_SHA256_ALT
 //#define MBEDTLS_SHA512_ALT
 
 /**
diff --git a/tests/include/alt-dummy/sha256_alt.h b/tests/include/alt-dummy/sha256_alt.h
deleted file mode 100644
index b1900ad..0000000
--- a/tests/include/alt-dummy/sha256_alt.h
+++ /dev/null
@@ -1,16 +0,0 @@
-/* sha256_alt.h with dummy types for MBEDTLS_SHA256_ALT */
-/*
- *  Copyright The Mbed TLS Contributors
- *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
- */
-
-#ifndef SHA256_ALT_H
-#define SHA256_ALT_H
-
-typedef struct mbedtls_sha256_context {
-    int dummy;
-}
-mbedtls_sha256_context;
-
-
-#endif /* sha256_alt.h */
diff --git a/tf-psa-crypto/drivers/builtin/include/mbedtls/sha256.h b/tf-psa-crypto/drivers/builtin/include/mbedtls/sha256.h
index ca568e2..0253f7d 100644
--- a/tf-psa-crypto/drivers/builtin/include/mbedtls/sha256.h
+++ b/tf-psa-crypto/drivers/builtin/include/mbedtls/sha256.h
@@ -26,10 +26,6 @@
 extern "C" {
 #endif
 
-#if !defined(MBEDTLS_SHA256_ALT)
-// Regular implementation
-//
-
 /**
  * \brief          The SHA-256 context structure.
  *
@@ -48,10 +44,6 @@
 }
 mbedtls_sha256_context;
 
-#else  /* MBEDTLS_SHA256_ALT */
-#include "sha256_alt.h"
-#endif /* MBEDTLS_SHA256_ALT */
-
 /**
  * \brief          This function initializes a SHA-256 context.
  *
diff --git a/tf-psa-crypto/drivers/builtin/src/sha256.c b/tf-psa-crypto/drivers/builtin/src/sha256.c
index 8b2c345..ec1e969 100644
--- a/tf-psa-crypto/drivers/builtin/src/sha256.c
+++ b/tf-psa-crypto/drivers/builtin/src/sha256.c
@@ -216,8 +216,6 @@
 
 #endif  /* MBEDTLS_SHA256_USE_ARMV8_A_CRYPTO_IF_PRESENT */
 
-#if !defined(MBEDTLS_SHA256_ALT)
-
 #define SHA256_BLOCK_SIZE 64
 
 void mbedtls_sha256_init(mbedtls_sha256_context *ctx)
@@ -763,8 +761,6 @@
     return ret;
 }
 
-#endif /* !MBEDTLS_SHA256_ALT */
-
 /*
  * output = SHA-256( input buffer )
  */