/* Copyright (C) 2004-2006, Advanced Micro Devices, Inc. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. */ #include <linux/module.h> #include <linux/kernel.h> #include <linux/pci.h> #include <linux/pci_ids.h> #include <linux/crypto.h> #include <linux/spinlock.h> #include <crypto/algapi.h> #include <asm/io.h> #include <asm/delay.h> #include "geode-aes.h" /* Register definitions */ #define AES_CTRLA_REG 0x0000 #define AES_CTRL_START 0x01 #define AES_CTRL_DECRYPT 0x00 #define AES_CTRL_ENCRYPT 0x02 #define AES_CTRL_WRKEY 0x04 #define AES_CTRL_DCA 0x08 #define AES_CTRL_SCA 0x10 #define AES_CTRL_CBC 0x20 #define AES_INTR_REG 0x0008 #define AES_INTRA_PENDING (1 << 16) #define AES_INTRB_PENDING (1 << 17) #define AES_INTR_PENDING (AES_INTRA_PENDING | AES_INTRB_PENDING) #define AES_INTR_MASK 0x07 #define AES_SOURCEA_REG 0x0010 #define AES_DSTA_REG 0x0014 #define AES_LENA_REG 0x0018 #define AES_WRITEKEY0_REG 0x0030 #define AES_WRITEIV0_REG 0x0040 /* A very large counter that is used to gracefully bail out of an * operation in case of trouble */ #define AES_OP_TIMEOUT 0x50000 /* Static structures */ static void __iomem * _iobase; static spinlock_t lock; /* Write a 128 bit field (either a writable key or IV) */ static inline void _writefield(u32 offset, void *value) { int i; for(i = 0; i < 4; i++) iowrite32(((u32 *) value)[i], _iobase + offset + (i * 4)); } /* Read a 128 bit field (either a writable key or IV) */ static inline void _readfield(u32 offset, void *value) { int i; for(i = 0; i < 4; i++) ((u32 *) value)[i] = ioread32(_iobase + offset + (i * 4)); } static int do_crypt(void *src, void *dst, int len, u32 flags) { u32 status; u32 counter = AES_OP_TIMEOUT; iowrite32(virt_to_phys(src), _iobase + AES_SOURCEA_REG); iowrite32(virt_to_phys(dst), _iobase + AES_DSTA_REG); iowrite32(len, _iobase + AES_LENA_REG); /* Start the operation */ iowrite32(AES_CTRL_START | flags, _iobase + AES_CTRLA_REG); do status = ioread32(_iobase + AES_INTR_REG); while(!(status & AES_INTRA_PENDING) && --counter); /* Clear the event */ iowrite32((status & 0xFF) | AES_INTRA_PENDING, _iobase + AES_INTR_REG); return counter ? 0 : 1; } static unsigned int geode_aes_crypt(struct geode_aes_op *op) { u32 flags = 0; int iflags; if (op->len == 0 || op->src == op->dst) return 0; if (op->flags & AES_FLAGS_COHERENT) flags |= (AES_CTRL_DCA | AES_CTRL_SCA); if (op->dir == AES_DIR_ENCRYPT) flags |= AES_CTRL_ENCRYPT; /* Start the critical section */ spin_lock_irqsave(&lock, iflags); if (op->mode == AES_MODE_CBC) { flags |= AES_CTRL_CBC; _writefield(AES_WRITEIV0_REG, op->iv); } if (op->flags & AES_FLAGS_USRKEY) { flags |= AES_CTRL_WRKEY; _writefield(AES_WRITEKEY0_REG, op->key); } do_crypt(op->src, op->dst, op->len, flags); if (op->mode == AES_MODE_CBC) _readfield(AES_WRITEIV0_REG, op->iv); spin_unlock_irqrestore(&lock, iflags); return op->len; } /* CRYPTO-API Functions */ static int geode_setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int len) { struct geode_aes_op *op = crypto_tfm_ctx(tfm); if (len != AES_KEY_LENGTH) { tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN; return -EINVAL; } memcpy(op->key, key, len); return 0; } static void geode_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) { struct geode_aes_op *op = crypto_tfm_ctx(tfm); if ((out == NULL) || (in == NULL)) return; op->src = (void *) in; op->dst = (void *) out; op->mode = AES_MODE_ECB; op->flags = 0; op->len = AES_MIN_BLOCK_SIZE; op->dir = AES_DIR_ENCRYPT; geode_aes_crypt(op); } static void geode_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in) { struct geode_aes_op *op = crypto_tfm_ctx(tfm); if ((out == NULL) || (in == NULL)) return; op->src = (void *) in; op->dst = (void *) out; op->mode = AES_MODE_ECB; op->flags = 0; op->len = AES_MIN_BLOCK_SIZE; op->dir = AES_DIR_DECRYPT; geode_aes_crypt(op); } static struct crypto_alg geode_alg = { .cra_name = "aes", .cra_driver_name = "geode-aes-128", .cra_priority = 300, .cra_alignmask = 15, .cra_flags = CRYPTO_ALG_TYPE_CIPHER, .cra_blocksize = AES_MIN_BLOCK_SIZE, .cra_ctxsize = sizeof(struct geode_aes_op), .cra_module = THIS_MODULE, .cra_list = LIST_HEAD_INIT(geode_alg.cra_list), .cra_u = { .cipher = { .cia_min_keysize = AES_KEY_LENGTH, .cia_max_keysize = AES_KEY_LENGTH, .cia_setkey = geode_setkey, .cia_encrypt = geode_encrypt, .cia_decrypt = geode_decrypt } } }; static int geode_cbc_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { struct geode_aes_op *op = crypto_blkcipher_ctx(desc->tfm); struct blkcipher_walk walk; int err, ret; blkcipher_walk_init(&walk, dst, src, nbytes); err = blkcipher_walk_virt(desc, &walk); while((nbytes = walk.nbytes)) { op->src = walk.src.virt.addr, op->dst = walk.dst.virt.addr; op->mode = AES_MODE_CBC; op->len = nbytes - (nbytes % AES_MIN_BLOCK_SIZE); op->dir = AES_DIR_DECRYPT; memcpy(op->iv, walk.iv, AES_IV_LENGTH); ret = geode_aes_crypt(op); memcpy(walk.iv, op->iv, AES_IV_LENGTH); nbytes -= ret; err = blkcipher_walk_done(desc, &walk, nbytes); } return err; } static int geode_cbc_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { struct geode_aes_op *op = crypto_blkcipher_ctx(desc->tfm); struct blkcipher_walk walk; int err, ret; blkcipher_walk_init(&walk, dst, src, nbytes); err = blkcipher_walk_virt(desc, &walk); while((nbytes = walk.nbytes)) { op->src = walk.src.virt.addr, op->dst = walk.dst.virt.addr; op->mode = AES_MODE_CBC; op->len = nbytes - (nbytes % AES_MIN_BLOCK_SIZE); op->dir = AES_DIR_ENCRYPT; memcpy(op->iv, walk.iv, AES_IV_LENGTH); ret = geode_aes_crypt(op); nbytes -= ret; err = blkcipher_walk_done(desc, &walk, nbytes); } return err; } static struct crypto_alg geode_cbc_alg = { .cra_name = "cbc(aes)", .cra_driver_name = "cbc-aes-geode-128", .cra_priority = 400, .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER, .cra_blocksize = AES_MIN_BLOCK_SIZE, .cra_ctxsize = sizeof(struct geode_aes_op), .cra_alignmask = 15, .cra_type = &crypto_blkcipher_type, .cra_module = THIS_MODULE, .cra_list = LIST_HEAD_INIT(geode_cbc_alg.cra_list), .cra_u = { .blkcipher = { .min_keysize = AES_KEY_LENGTH, .max_keysize = AES_KEY_LENGTH, .setkey = geode_setkey, .encrypt = geode_cbc_encrypt, .decrypt = geode_cbc_decrypt, } } }; static int geode_ecb_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { struct geode_aes_op *op = crypto_blkcipher_ctx(desc->tfm); struct blkcipher_walk walk; int err, ret; blkcipher_walk_init(&walk, dst, src, nbytes); err = blkcipher_walk_virt(desc, &walk); while((nbytes = walk.nbytes)) { op->src = walk.src.virt.addr, op->dst = walk.dst.virt.addr; op->mode = AES_MODE_ECB; op->len = nbytes - (nbytes % AES_MIN_BLOCK_SIZE); op->dir = AES_DIR_DECRYPT; ret = geode_aes_crypt(op); nbytes -= ret; err = blkcipher_walk_done(desc, &walk, nbytes); } return err; } static int geode_ecb_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { struct geode_aes_op *op = crypto_blkcipher_ctx(desc->tfm); struct blkcipher_walk walk; int err, ret; blkcipher_walk_init(&walk, dst, src, nbytes); err = blkcipher_walk_virt(desc, &walk); while((nbytes = walk.nbytes)) { op->src = walk.src.virt.addr, op->dst = walk.dst.virt.addr; op->mode = AES_MODE_ECB; op->len = nbytes - (nbytes % AES_MIN_BLOCK_SIZE); op->dir = AES_DIR_ENCRYPT; ret = geode_aes_crypt(op); nbytes -= ret; ret = blkcipher_walk_done(desc, &walk, nbytes); } return err; } static struct crypto_alg geode_ecb_alg = { .cra_name = "ecb(aes)", .cra_driver_name = "ecb-aes-geode-128", .cra_priority = 400, .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER, .cra_blocksize = AES_MIN_BLOCK_SIZE, .cra_ctxsize = sizeof(struct geode_aes_op), .cra_alignmask = 15, .cra_type = &crypto_blkcipher_type, .cra_module = THIS_MODULE, .cra_list = LIST_HEAD_INIT(geode_ecb_alg.cra_list), .cra_u = { .blkcipher = { .min_keysize = AES_KEY_LENGTH, .max_keysize = AES_KEY_LENGTH, .setkey = geode_setkey, .encrypt = geode_ecb_encrypt, .decrypt = geode_ecb_decrypt, } } }; static void geode_aes_remove(struct pci_dev *dev) { crypto_unregister_alg(&geode_alg); crypto_unregister_alg(&geode_ecb_alg); crypto_unregister_alg(&geode_cbc_alg); pci_iounmap(dev, _iobase); _iobase = NULL; pci_release_regions(dev); pci_disable_device(dev); } static int geode_aes_probe(struct pci_dev *dev, const struct pci_device_id *id) { int ret; if ((ret = pci_enable_device(dev))) return ret; if ((ret = pci_request_regions(dev, "geode-aes-128"))) goto eenable; _iobase = pci_iomap(dev, 0, 0); if (_iobase == NULL) { ret = -ENOMEM; goto erequest; } spin_lock_init(&lock); /* Clear any pending activity */ iowrite32(AES_INTR_PENDING | AES_INTR_MASK, _iobase + AES_INTR_REG); if ((ret = crypto_register_alg(&geode_alg))) goto eiomap; if ((ret = crypto_register_alg(&geode_ecb_alg))) goto ealg; if ((ret = crypto_register_alg(&geode_cbc_alg))) goto eecb; printk(KERN_NOTICE "geode-aes: GEODE AES engine enabled.\n"); return 0; eecb: crypto_unregister_alg(&geode_ecb_alg); ealg: crypto_unregister_alg(&geode_alg); eiomap: pci_iounmap(dev, _iobase); erequest: pci_release_regions(dev); eenable: pci_disable_device(dev); printk(KERN_ERR "geode-aes: GEODE AES initialization failed.\n"); return ret; } static struct pci_device_id geode_aes_tbl[] = { { PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_LX_AES, PCI_ANY_ID, PCI_ANY_ID} , { 0, } }; MODULE_DEVICE_TABLE(pci, geode_aes_tbl); static struct pci_driver geode_aes_driver = { .name = "Geode LX AES", .id_table = geode_aes_tbl, .probe = geode_aes_probe, .remove = __devexit_p(geode_aes_remove) }; static int __init geode_aes_init(void) { return pci_register_driver(&geode_aes_driver); } static void __exit geode_aes_exit(void) { pci_unregister_driver(&geode_aes_driver); } MODULE_AUTHOR("Advanced Micro Devices, Inc."); MODULE_DESCRIPTION("Geode LX Hardware AES driver"); MODULE_LICENSE("GPL"); module_init(geode_aes_init); module_exit(geode_aes_exit);