/* * 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);