diff options
Diffstat (limited to 'kernel/arch/mips/cavium-octeon/crypto/octeon-crypto.c')
| -rw-r--r-- | kernel/arch/mips/cavium-octeon/crypto/octeon-crypto.c | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/kernel/arch/mips/cavium-octeon/crypto/octeon-crypto.c b/kernel/arch/mips/cavium-octeon/crypto/octeon-crypto.c new file mode 100644 index 000000000..f66bd1adc --- /dev/null +++ b/kernel/arch/mips/cavium-octeon/crypto/octeon-crypto.c @@ -0,0 +1,68 @@ +/* + * 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. + * 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); |