1*4882a593Smuzhiyun /* 2*4882a593Smuzhiyun * This file is subject to the terms and conditions of the GNU General Public 3*4882a593Smuzhiyun * License. See the file "COPYING" in the main directory of this archive 4*4882a593Smuzhiyun * for more details. 5*4882a593Smuzhiyun * 6*4882a593Smuzhiyun * Copyright (C) 2004-2012 Cavium Networks 7*4882a593Smuzhiyun */ 8*4882a593Smuzhiyun 9*4882a593Smuzhiyun #include <asm/cop2.h> 10*4882a593Smuzhiyun #include <linux/export.h> 11*4882a593Smuzhiyun #include <linux/interrupt.h> 12*4882a593Smuzhiyun #include <linux/sched/task_stack.h> 13*4882a593Smuzhiyun 14*4882a593Smuzhiyun #include "octeon-crypto.h" 15*4882a593Smuzhiyun 16*4882a593Smuzhiyun /** 17*4882a593Smuzhiyun * Enable access to Octeon's COP2 crypto hardware for kernel use. Wrap any 18*4882a593Smuzhiyun * crypto operations in calls to octeon_crypto_enable/disable in order to make 19*4882a593Smuzhiyun * sure the state of COP2 isn't corrupted if userspace is also performing 20*4882a593Smuzhiyun * hardware crypto operations. Allocate the state parameter on the stack. 21*4882a593Smuzhiyun * Returns with preemption disabled. 22*4882a593Smuzhiyun * 23*4882a593Smuzhiyun * @state: Pointer to state structure to store current COP2 state in. 24*4882a593Smuzhiyun * 25*4882a593Smuzhiyun * Returns: Flags to be passed to octeon_crypto_disable() 26*4882a593Smuzhiyun */ octeon_crypto_enable(struct octeon_cop2_state * state)27*4882a593Smuzhiyununsigned long octeon_crypto_enable(struct octeon_cop2_state *state) 28*4882a593Smuzhiyun { 29*4882a593Smuzhiyun int status; 30*4882a593Smuzhiyun unsigned long flags; 31*4882a593Smuzhiyun 32*4882a593Smuzhiyun preempt_disable(); 33*4882a593Smuzhiyun local_irq_save(flags); 34*4882a593Smuzhiyun status = read_c0_status(); 35*4882a593Smuzhiyun write_c0_status(status | ST0_CU2); 36*4882a593Smuzhiyun if (KSTK_STATUS(current) & ST0_CU2) { 37*4882a593Smuzhiyun octeon_cop2_save(&(current->thread.cp2)); 38*4882a593Smuzhiyun KSTK_STATUS(current) &= ~ST0_CU2; 39*4882a593Smuzhiyun status &= ~ST0_CU2; 40*4882a593Smuzhiyun } else if (status & ST0_CU2) { 41*4882a593Smuzhiyun octeon_cop2_save(state); 42*4882a593Smuzhiyun } 43*4882a593Smuzhiyun local_irq_restore(flags); 44*4882a593Smuzhiyun return status & ST0_CU2; 45*4882a593Smuzhiyun } 46*4882a593Smuzhiyun EXPORT_SYMBOL_GPL(octeon_crypto_enable); 47*4882a593Smuzhiyun 48*4882a593Smuzhiyun /** 49*4882a593Smuzhiyun * Disable access to Octeon's COP2 crypto hardware in the kernel. This must be 50*4882a593Smuzhiyun * called after an octeon_crypto_enable() before any context switch or return to 51*4882a593Smuzhiyun * userspace. 52*4882a593Smuzhiyun * 53*4882a593Smuzhiyun * @state: Pointer to COP2 state to restore 54*4882a593Smuzhiyun * @flags: Return value from octeon_crypto_enable() 55*4882a593Smuzhiyun */ octeon_crypto_disable(struct octeon_cop2_state * state,unsigned long crypto_flags)56*4882a593Smuzhiyunvoid octeon_crypto_disable(struct octeon_cop2_state *state, 57*4882a593Smuzhiyun unsigned long crypto_flags) 58*4882a593Smuzhiyun { 59*4882a593Smuzhiyun unsigned long flags; 60*4882a593Smuzhiyun 61*4882a593Smuzhiyun local_irq_save(flags); 62*4882a593Smuzhiyun if (crypto_flags & ST0_CU2) 63*4882a593Smuzhiyun octeon_cop2_restore(state); 64*4882a593Smuzhiyun else 65*4882a593Smuzhiyun write_c0_status(read_c0_status() & ~ST0_CU2); 66*4882a593Smuzhiyun local_irq_restore(flags); 67*4882a593Smuzhiyun preempt_enable(); 68*4882a593Smuzhiyun } 69*4882a593Smuzhiyun EXPORT_SYMBOL_GPL(octeon_crypto_disable); 70