ice: fix issue with losing ICE key configuration during reset

TZ is called to restore key configuration in case of UFS reset

Change-Id: Id434e7f9ec6befdce97f52fd350957b66adcb15f
Signed-off-by: Andrey Markovytch <andreym@codeaurora.org>

drivers/crypto/msm/ice.c

@@ -24,6 +24,7 @@
 #include <linux/pfk.h>
 #include <crypto/ice.h>
 #include <soc/qcom/scm.h>
+#include <soc/qcom/qseecomi.h>
 #include "iceregs.h"
 
 #define TZ_SYSCALL_CREATE_SMC_ID(o, s, f) \
@@ -40,6 +41,13 @@
 #define TZ_OS_KS_RESTORE_KEY_ID_PARAM_ID \
 	TZ_SYSCALL_CREATE_PARAM_ID_0
 
+#define TZ_OS_KS_RESTORE_KEY_CONFIG_ID \
+	TZ_SYSCALL_CREATE_SMC_ID(TZ_OWNER_QSEE_OS, TZ_SVC_KEYSTORE, 0x06)
+
+#define TZ_OS_KS_RESTORE_KEY_CONFIG_ID_PARAM_ID \
+	TZ_SYSCALL_CREATE_PARAM_ID_1(TZ_SYSCALL_PARAM_TYPE_VAL)
+
+
 #define ICE_REV(x, y) (((x) & ICE_CORE_##y##_REV_MASK) >> ICE_CORE_##y##_REV)
 #define QCOM_UFS_ICE_DEV	"iceufs"
 #define QCOM_SDCC_ICE_DEV	"icesdcc"
@@ -830,6 +838,24 @@ static int qcom_ice_restore_config(void)
 	return ret;
 }
 
+static int qcom_ice_restore_key_config(void)
+{
+	struct scm_desc desc = {0};
+	int ret = -1;
+
+	/* For ice 3, key configuration needs to be restored in case of reset */
+
+	desc.arginfo = TZ_OS_KS_RESTORE_KEY_CONFIG_ID_PARAM_ID;
+	desc.args[0] = 10; /* UFS_ICE */
+
+	ret = scm_call2(TZ_OS_KS_RESTORE_KEY_CONFIG_ID, &desc);
+
+	if (ret)
+		pr_err("%s: Error:  0x%x\n", __func__, ret);
+
+	return ret;
+}
+
 static int qcom_ice_init_clocks(struct ice_device *ice)
 {
 	int ret = -EINVAL;
@@ -1103,6 +1129,22 @@ static int qcom_ice_finish_power_collapse(struct ice_device *ice_dev)
 				err = -EFAULT;
 				goto out;
 			}
+
+		/*
+		 * ICE looses its key configuration when UFS is reset,
+		 * restore it
+		 */
+		} else if (ICE_REV(ice_dev->ice_hw_version, MAJOR) > 2) {
+			err = qcom_ice_restore_key_config();
+			if (err)
+				goto out;
+
+			/*
+			 * for PFE case, clear the cached ICE key table,
+			 * this will force keys to be reconfigured
+			 * per each next transaction
+			 */
+			pfk_clear_on_reset();
 		}
 	}
 

include/linux/pfk.h

@@ -1,4 +1,4 @@
-/* Copyright (c) 2015-2016, The Linux Foundation. All rights reserved.
+/* Copyright (c) 2015-2017, The Linux Foundation. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 and
@@ -24,6 +24,7 @@ int pfk_load_key_start(const struct bio *bio,
 int pfk_load_key_end(const struct bio *bio, bool *is_pfe);
 int pfk_remove_key(const unsigned char *key, size_t key_size);
 bool pfk_allow_merge_bio(const struct bio *bio1, const struct bio *bio2);
+void pfk_clear_on_reset(void);
 
 #else
 static inline int pfk_load_key_start(const struct bio *bio,
@@ -48,6 +49,9 @@ static inline bool pfk_allow_merge_bio(const struct bio *bio1,
 	return true;
 }
 
+static inline void pfk_clear_on_reset(void)
+{}
+
 #endif /* CONFIG_PFK */
 
 #endif /* PFK_H */

security/pfe/pfk.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2016, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2015-2017, The Linux Foundation. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 and
@@ -476,6 +476,18 @@ bool pfk_allow_merge_bio(const struct bio *bio1, const struct bio *bio2)
 	return (*(pfk_allow_merge_bio_ftable[which_pfe1]))(bio1, bio2,
 		inode1, inode2);
 }
+/**
+ * Flush key table on storage core reset. During core reset key configuration
+ * is lost in ICE. We need to flash the cache, so that the keys will be
+ * reconfigured again for every subsequent transaction
+ */
+void pfk_clear_on_reset(void)
+{
+	if (!pfk_is_ready())
+		return;
+
+	pfk_kc_clear_on_reset();
+}
 
 module_init(pfk_init);
 module_exit(pfk_exit);

security/pfe/pfk_kc.c

@@ -826,3 +826,27 @@ out:
 
 	return res;
 }
+
+/**
+ * pfk_kc_clear_on_reset() - clear the table and remove all keys from ICE
+ * The assumption is that at this point we don't have any pending transactions
+ * Also, there is no need to clear keys from ICE
+ *
+ * Return 0 on success, error otherwise
+ *
+ */
+void pfk_kc_clear_on_reset(void)
+{
+	struct kc_entry *entry = NULL;
+	int i = 0;
+
+	if (!kc_is_ready())
+		return;
+
+	kc_spin_lock();
+	for (i = 0; i < PFK_KC_TABLE_SIZE; i++) {
+		entry = kc_entry_at_index(i);
+		kc_clear_entry(entry);
+	}
+	kc_spin_unlock();
+}

security/pfe/pfk_kc.h

@@ -1,4 +1,4 @@
-/* Copyright (c) 2015-2016, The Linux Foundation. All rights reserved.
+/* Copyright (c) 2015-2017, The Linux Foundation. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 and
@@ -26,6 +26,7 @@ int pfk_kc_remove_key_with_salt(const unsigned char *key, size_t key_size,
 		const unsigned char *salt, size_t salt_size);
 int pfk_kc_remove_key(const unsigned char *key, size_t key_size);
 int pfk_kc_clear(void);
+void pfk_kc_clear_on_reset(void);