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path: root/drivers/crypto/ccree/cc_fips.c
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Diffstat (limited to 'drivers/crypto/ccree/cc_fips.c')
-rw-r--r--drivers/crypto/ccree/cc_fips.c154
1 files changed, 154 insertions, 0 deletions
diff --git a/drivers/crypto/ccree/cc_fips.c b/drivers/crypto/ccree/cc_fips.c
new file mode 100644
index 000000000..702aefc21
--- /dev/null
+++ b/drivers/crypto/ccree/cc_fips.c
@@ -0,0 +1,154 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) 2012-2019 ARM Limited (or its affiliates). */
+
+#include <linux/kernel.h>
+#include <linux/fips.h>
+#include <linux/notifier.h>
+
+#include "cc_driver.h"
+#include "cc_fips.h"
+
+static void fips_dsr(unsigned long devarg);
+
+struct cc_fips_handle {
+ struct tasklet_struct tasklet;
+ struct notifier_block nb;
+ struct cc_drvdata *drvdata;
+};
+
+/* The function called once at driver entry point to check
+ * whether TEE FIPS error occurred.
+ */
+static bool cc_get_tee_fips_status(struct cc_drvdata *drvdata)
+{
+ u32 reg;
+
+ reg = cc_ioread(drvdata, CC_REG(GPR_HOST));
+ /* Did the TEE report status? */
+ if (reg & CC_FIPS_SYNC_TEE_STATUS)
+ /* Yes. Is it OK? */
+ return (reg & CC_FIPS_SYNC_MODULE_OK);
+
+ /* No. It's either not in use or will be reported later */
+ return true;
+}
+
+/*
+ * This function should push the FIPS REE library status towards the TEE library
+ * by writing the error state to HOST_GPR0 register.
+ */
+void cc_set_ree_fips_status(struct cc_drvdata *drvdata, bool status)
+{
+ int val = CC_FIPS_SYNC_REE_STATUS;
+
+ if (drvdata->hw_rev < CC_HW_REV_712)
+ return;
+
+ val |= (status ? CC_FIPS_SYNC_MODULE_OK : CC_FIPS_SYNC_MODULE_ERROR);
+
+ cc_iowrite(drvdata, CC_REG(HOST_GPR0), val);
+}
+
+/* Push REE side FIPS test failure to TEE side */
+static int cc_ree_fips_failure(struct notifier_block *nb, unsigned long unused1,
+ void *unused2)
+{
+ struct cc_fips_handle *fips_h =
+ container_of(nb, struct cc_fips_handle, nb);
+ struct cc_drvdata *drvdata = fips_h->drvdata;
+ struct device *dev = drvdata_to_dev(drvdata);
+
+ cc_set_ree_fips_status(drvdata, false);
+ dev_info(dev, "Notifying TEE of FIPS test failure...\n");
+
+ return NOTIFY_OK;
+}
+
+void cc_fips_fini(struct cc_drvdata *drvdata)
+{
+ struct cc_fips_handle *fips_h = drvdata->fips_handle;
+
+ if (drvdata->hw_rev < CC_HW_REV_712 || !fips_h)
+ return;
+
+ atomic_notifier_chain_unregister(&fips_fail_notif_chain, &fips_h->nb);
+
+ /* Kill tasklet */
+ tasklet_kill(&fips_h->tasklet);
+ drvdata->fips_handle = NULL;
+}
+
+void fips_handler(struct cc_drvdata *drvdata)
+{
+ struct cc_fips_handle *fips_handle_ptr = drvdata->fips_handle;
+
+ if (drvdata->hw_rev < CC_HW_REV_712)
+ return;
+
+ tasklet_schedule(&fips_handle_ptr->tasklet);
+}
+
+static inline void tee_fips_error(struct device *dev)
+{
+ if (fips_enabled)
+ panic("ccree: TEE reported cryptographic error in fips mode!\n");
+ else
+ dev_err(dev, "TEE reported error!\n");
+}
+
+/*
+ * This function check if cryptocell tee fips error occurred
+ * and in such case triggers system error
+ */
+void cc_tee_handle_fips_error(struct cc_drvdata *p_drvdata)
+{
+ struct device *dev = drvdata_to_dev(p_drvdata);
+
+ if (!cc_get_tee_fips_status(p_drvdata))
+ tee_fips_error(dev);
+}
+
+/* Deferred service handler, run as interrupt-fired tasklet */
+static void fips_dsr(unsigned long devarg)
+{
+ struct cc_drvdata *drvdata = (struct cc_drvdata *)devarg;
+ u32 irq, val;
+
+ irq = (drvdata->irq & (CC_GPR0_IRQ_MASK));
+
+ if (irq) {
+ cc_tee_handle_fips_error(drvdata);
+ }
+
+ /* after verifying that there is nothing to do,
+ * unmask AXI completion interrupt.
+ */
+ val = (CC_REG(HOST_IMR) & ~irq);
+ cc_iowrite(drvdata, CC_REG(HOST_IMR), val);
+}
+
+/* The function called once at driver entry point .*/
+int cc_fips_init(struct cc_drvdata *p_drvdata)
+{
+ struct cc_fips_handle *fips_h;
+ struct device *dev = drvdata_to_dev(p_drvdata);
+
+ if (p_drvdata->hw_rev < CC_HW_REV_712)
+ return 0;
+
+ fips_h = devm_kzalloc(dev, sizeof(*fips_h), GFP_KERNEL);
+ if (!fips_h)
+ return -ENOMEM;
+
+ p_drvdata->fips_handle = fips_h;
+
+ dev_dbg(dev, "Initializing fips tasklet\n");
+ tasklet_init(&fips_h->tasklet, fips_dsr, (unsigned long)p_drvdata);
+ fips_h->drvdata = p_drvdata;
+ fips_h->nb.notifier_call = cc_ree_fips_failure;
+ atomic_notifier_chain_register(&fips_fail_notif_chain, &fips_h->nb);
+
+ cc_tee_handle_fips_error(p_drvdata);
+
+ return 0;
+}