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-rw-r--r--arch/mips/cavium-octeon/crypto/octeon-crypto.c66
1 files changed, 66 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 0000000..7c82ff4
--- /dev/null
+++ b/arch/mips/cavium-octeon/crypto/octeon-crypto.c
@@ -0,0 +1,66 @@
+/*
+ * 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/module.h>
+#include <linux/interrupt.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.
+ * Preemption must be disabled to prevent context switches.
+ *
+ * @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;
+
+ 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);
+}
+EXPORT_SYMBOL_GPL(octeon_crypto_disable);

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