1 // SPDX-License-Identifier: GPL-2.0 2 /* Copyright (C) 2012-2019 ARM Limited (or its affiliates). */ 3 4 #include <linux/kernel.h> 5 #include <linux/fips.h> 6 7 #include "cc_driver.h" 8 #include "cc_fips.h" 9 10 static void fips_dsr(unsigned long devarg); 11 12 struct cc_fips_handle { 13 struct tasklet_struct tasklet; 14 }; 15 16 /* The function called once at driver entry point to check 17 * whether TEE FIPS error occurred. 18 */ 19 static bool cc_get_tee_fips_status(struct cc_drvdata *drvdata) 20 { 21 u32 reg; 22 23 reg = cc_ioread(drvdata, CC_REG(GPR_HOST)); 24 return (reg == (CC_FIPS_SYNC_TEE_STATUS | CC_FIPS_SYNC_MODULE_OK)); 25 } 26 27 /* 28 * This function should push the FIPS REE library status towards the TEE library 29 * by writing the error state to HOST_GPR0 register. 30 */ 31 void cc_set_ree_fips_status(struct cc_drvdata *drvdata, bool status) 32 { 33 int val = CC_FIPS_SYNC_REE_STATUS; 34 35 if (drvdata->hw_rev < CC_HW_REV_712) 36 return; 37 38 val |= (status ? CC_FIPS_SYNC_MODULE_OK : CC_FIPS_SYNC_MODULE_ERROR); 39 40 cc_iowrite(drvdata, CC_REG(HOST_GPR0), val); 41 } 42 43 void cc_fips_fini(struct cc_drvdata *drvdata) 44 { 45 struct cc_fips_handle *fips_h = drvdata->fips_handle; 46 47 if (drvdata->hw_rev < CC_HW_REV_712 || !fips_h) 48 return; 49 50 /* Kill tasklet */ 51 tasklet_kill(&fips_h->tasklet); 52 drvdata->fips_handle = NULL; 53 } 54 55 void fips_handler(struct cc_drvdata *drvdata) 56 { 57 struct cc_fips_handle *fips_handle_ptr = drvdata->fips_handle; 58 59 if (drvdata->hw_rev < CC_HW_REV_712) 60 return; 61 62 tasklet_schedule(&fips_handle_ptr->tasklet); 63 } 64 65 static inline void tee_fips_error(struct device *dev) 66 { 67 if (fips_enabled) 68 panic("ccree: TEE reported cryptographic error in fips mode!\n"); 69 else 70 dev_err(dev, "TEE reported error!\n"); 71 } 72 73 /* 74 * This function check if cryptocell tee fips error occurred 75 * and in such case triggers system error 76 */ 77 void cc_tee_handle_fips_error(struct cc_drvdata *p_drvdata) 78 { 79 struct device *dev = drvdata_to_dev(p_drvdata); 80 81 if (!cc_get_tee_fips_status(p_drvdata)) 82 tee_fips_error(dev); 83 } 84 85 /* Deferred service handler, run as interrupt-fired tasklet */ 86 static void fips_dsr(unsigned long devarg) 87 { 88 struct cc_drvdata *drvdata = (struct cc_drvdata *)devarg; 89 u32 irq, val; 90 91 irq = (drvdata->irq & (CC_GPR0_IRQ_MASK)); 92 93 if (irq) { 94 cc_tee_handle_fips_error(drvdata); 95 } 96 97 /* after verifing that there is nothing to do, 98 * unmask AXI completion interrupt. 99 */ 100 val = (CC_REG(HOST_IMR) & ~irq); 101 cc_iowrite(drvdata, CC_REG(HOST_IMR), val); 102 } 103 104 /* The function called once at driver entry point .*/ 105 int cc_fips_init(struct cc_drvdata *p_drvdata) 106 { 107 struct cc_fips_handle *fips_h; 108 struct device *dev = drvdata_to_dev(p_drvdata); 109 110 if (p_drvdata->hw_rev < CC_HW_REV_712) 111 return 0; 112 113 fips_h = devm_kzalloc(dev, sizeof(*fips_h), GFP_KERNEL); 114 if (!fips_h) 115 return -ENOMEM; 116 117 p_drvdata->fips_handle = fips_h; 118 119 dev_dbg(dev, "Initializing fips tasklet\n"); 120 tasklet_init(&fips_h->tasklet, fips_dsr, (unsigned long)p_drvdata); 121 122 cc_tee_handle_fips_error(p_drvdata); 123 124 return 0; 125 } 126