1 files changed, 69 insertions, 0 deletions
diff --git a/arch/mips/cavium-octeon/crypto/octeon-crypto.c b/arch/mips/cavium-octeon/crypto/octeon-crypto.c
new file mode 100644
index 0000000000..cfb4a146cf
--- /dev/null
+++ b/arch/mips/cavium-octeon/crypto/octeon-crypto.c
@@ -0,0 +1,69 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2004-2012 Cavium Networks
+ */
+
+#include <asm/cop2.h>
+#include <linux/export.h>
+#include <linux/interrupt.h>
+#include <linux/sched/task_stack.h>
+
+#include "octeon-crypto.h"
+
+/**
+ * Enable access to Octeon's COP2 crypto hardware for kernel use. Wrap any
+ * crypto operations in calls to octeon_crypto_enable/disable in order to make
+ * sure the state of COP2 isn't corrupted if userspace is also performing
+ * hardware crypto operations. Allocate the state parameter on the stack.
+ * Returns with preemption disabled.
+ *
+ * @state: Pointer to state structure to store current COP2 state in.
+ *
+ * Returns: Flags to be passed to octeon_crypto_disable()
+ */
+unsigned long octeon_crypto_enable(struct octeon_cop2_state *state)
+{
+	int status;
+	unsigned long flags;
+
+	preempt_disable();
+	local_irq_save(flags);
+	status = read_c0_status();
+	write_c0_status(status | ST0_CU2);
+	if (KSTK_STATUS(current) & ST0_CU2) {
+		octeon_cop2_save(&(current->thread.cp2));
+		KSTK_STATUS(current) &= ~ST0_CU2;
+		status &= ~ST0_CU2;
+	} else if (status & ST0_CU2) {
+		octeon_cop2_save(state);
+	}
+	local_irq_restore(flags);
+	return status & ST0_CU2;
+}
+EXPORT_SYMBOL_GPL(octeon_crypto_enable);
+
+/**
+ * Disable access to Octeon's COP2 crypto hardware in the kernel. This must be
+ * called after an octeon_crypto_enable() before any context switch or return to
+ * userspace.
+ *
+ * @state:	Pointer to COP2 state to restore
+ * @flags:	Return value from octeon_crypto_enable()
+ */
+void octeon_crypto_disable(struct octeon_cop2_state *state,
+			   unsigned long crypto_flags)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	if (crypto_flags & ST0_CU2)
+		octeon_cop2_restore(state);
+	else
+		write_c0_status(read_c0_status() & ~ST0_CU2);
+	local_irq_restore(flags);
+	preempt_enable();
+}
+EXPORT_SYMBOL_GPL(octeon_crypto_disable);