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path: root/drivers/crypto/mv_cesa.c
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Diffstat (limited to 'drivers/crypto/mv_cesa.c')
-rw-r--r--drivers/crypto/mv_cesa.c606
1 files changed, 606 insertions, 0 deletions
diff --git a/drivers/crypto/mv_cesa.c b/drivers/crypto/mv_cesa.c
new file mode 100644
index 000000000000..b21ef635f352
--- /dev/null
+++ b/drivers/crypto/mv_cesa.c
@@ -0,0 +1,606 @@
+/*
+ * Support for Marvell's crypto engine which can be found on some Orion5X
+ * boards.
+ *
+ * Author: Sebastian Andrzej Siewior < sebastian at breakpoint dot cc >
+ * License: GPLv2
+ *
+ */
+#include <crypto/aes.h>
+#include <crypto/algapi.h>
+#include <linux/crypto.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kthread.h>
+#include <linux/platform_device.h>
+#include <linux/scatterlist.h>
+
+#include "mv_cesa.h"
+/*
+ * STM:
+ * /---------------------------------------\
+ * | | request complete
+ * \./ |
+ * IDLE -> new request -> BUSY -> done -> DEQUEUE
+ * /°\ |
+ * | | more scatter entries
+ * \________________/
+ */
+enum engine_status {
+ ENGINE_IDLE,
+ ENGINE_BUSY,
+ ENGINE_W_DEQUEUE,
+};
+
+/**
+ * struct req_progress - used for every crypt request
+ * @src_sg_it: sg iterator for src
+ * @dst_sg_it: sg iterator for dst
+ * @sg_src_left: bytes left in src to process (scatter list)
+ * @src_start: offset to add to src start position (scatter list)
+ * @crypt_len: length of current crypt process
+ * @sg_dst_left: bytes left dst to process in this scatter list
+ * @dst_start: offset to add to dst start position (scatter list)
+ * @total_req_bytes: total number of bytes processed (request).
+ *
+ * sg helper are used to iterate over the scatterlist. Since the size of the
+ * SRAM may be less than the scatter size, this struct struct is used to keep
+ * track of progress within current scatterlist.
+ */
+struct req_progress {
+ struct sg_mapping_iter src_sg_it;
+ struct sg_mapping_iter dst_sg_it;
+
+ /* src mostly */
+ int sg_src_left;
+ int src_start;
+ int crypt_len;
+ /* dst mostly */
+ int sg_dst_left;
+ int dst_start;
+ int total_req_bytes;
+};
+
+struct crypto_priv {
+ void __iomem *reg;
+ void __iomem *sram;
+ int irq;
+ struct task_struct *queue_th;
+
+ /* the lock protects queue and eng_st */
+ spinlock_t lock;
+ struct crypto_queue queue;
+ enum engine_status eng_st;
+ struct ablkcipher_request *cur_req;
+ struct req_progress p;
+ int max_req_size;
+ int sram_size;
+};
+
+static struct crypto_priv *cpg;
+
+struct mv_ctx {
+ u8 aes_enc_key[AES_KEY_LEN];
+ u32 aes_dec_key[8];
+ int key_len;
+ u32 need_calc_aes_dkey;
+};
+
+enum crypto_op {
+ COP_AES_ECB,
+ COP_AES_CBC,
+};
+
+struct mv_req_ctx {
+ enum crypto_op op;
+ int decrypt;
+};
+
+static void compute_aes_dec_key(struct mv_ctx *ctx)
+{
+ struct crypto_aes_ctx gen_aes_key;
+ int key_pos;
+
+ if (!ctx->need_calc_aes_dkey)
+ return;
+
+ crypto_aes_expand_key(&gen_aes_key, ctx->aes_enc_key, ctx->key_len);
+
+ key_pos = ctx->key_len + 24;
+ memcpy(ctx->aes_dec_key, &gen_aes_key.key_enc[key_pos], 4 * 4);
+ switch (ctx->key_len) {
+ case AES_KEYSIZE_256:
+ key_pos -= 2;
+ /* fall */
+ case AES_KEYSIZE_192:
+ key_pos -= 2;
+ memcpy(&ctx->aes_dec_key[4], &gen_aes_key.key_enc[key_pos],
+ 4 * 4);
+ break;
+ }
+ ctx->need_calc_aes_dkey = 0;
+}
+
+static int mv_setkey_aes(struct crypto_ablkcipher *cipher, const u8 *key,
+ unsigned int len)
+{
+ struct crypto_tfm *tfm = crypto_ablkcipher_tfm(cipher);
+ struct mv_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ switch (len) {
+ case AES_KEYSIZE_128:
+ case AES_KEYSIZE_192:
+ case AES_KEYSIZE_256:
+ break;
+ default:
+ crypto_ablkcipher_set_flags(cipher, CRYPTO_TFM_RES_BAD_KEY_LEN);
+ return -EINVAL;
+ }
+ ctx->key_len = len;
+ ctx->need_calc_aes_dkey = 1;
+
+ memcpy(ctx->aes_enc_key, key, AES_KEY_LEN);
+ return 0;
+}
+
+static void setup_data_in(struct ablkcipher_request *req)
+{
+ int ret;
+ void *buf;
+
+ if (!cpg->p.sg_src_left) {
+ ret = sg_miter_next(&cpg->p.src_sg_it);
+ BUG_ON(!ret);
+ cpg->p.sg_src_left = cpg->p.src_sg_it.length;
+ cpg->p.src_start = 0;
+ }
+
+ cpg->p.crypt_len = min(cpg->p.sg_src_left, cpg->max_req_size);
+
+ buf = cpg->p.src_sg_it.addr;
+ buf += cpg->p.src_start;
+
+ memcpy(cpg->sram + SRAM_DATA_IN_START, buf, cpg->p.crypt_len);
+
+ cpg->p.sg_src_left -= cpg->p.crypt_len;
+ cpg->p.src_start += cpg->p.crypt_len;
+}
+
+static void mv_process_current_q(int first_block)
+{
+ struct ablkcipher_request *req = cpg->cur_req;
+ struct mv_ctx *ctx = crypto_tfm_ctx(req->base.tfm);
+ struct mv_req_ctx *req_ctx = ablkcipher_request_ctx(req);
+ struct sec_accel_config op;
+
+ switch (req_ctx->op) {
+ case COP_AES_ECB:
+ op.config = CFG_OP_CRYPT_ONLY | CFG_ENCM_AES | CFG_ENC_MODE_ECB;
+ break;
+ case COP_AES_CBC:
+ op.config = CFG_OP_CRYPT_ONLY | CFG_ENCM_AES | CFG_ENC_MODE_CBC;
+ op.enc_iv = ENC_IV_POINT(SRAM_DATA_IV) |
+ ENC_IV_BUF_POINT(SRAM_DATA_IV_BUF);
+ if (first_block)
+ memcpy(cpg->sram + SRAM_DATA_IV, req->info, 16);
+ break;
+ }
+ if (req_ctx->decrypt) {
+ op.config |= CFG_DIR_DEC;
+ memcpy(cpg->sram + SRAM_DATA_KEY_P, ctx->aes_dec_key,
+ AES_KEY_LEN);
+ } else {
+ op.config |= CFG_DIR_ENC;
+ memcpy(cpg->sram + SRAM_DATA_KEY_P, ctx->aes_enc_key,
+ AES_KEY_LEN);
+ }
+
+ switch (ctx->key_len) {
+ case AES_KEYSIZE_128:
+ op.config |= CFG_AES_LEN_128;
+ break;
+ case AES_KEYSIZE_192:
+ op.config |= CFG_AES_LEN_192;
+ break;
+ case AES_KEYSIZE_256:
+ op.config |= CFG_AES_LEN_256;
+ break;
+ }
+ op.enc_p = ENC_P_SRC(SRAM_DATA_IN_START) |
+ ENC_P_DST(SRAM_DATA_OUT_START);
+ op.enc_key_p = SRAM_DATA_KEY_P;
+
+ setup_data_in(req);
+ op.enc_len = cpg->p.crypt_len;
+ memcpy(cpg->sram + SRAM_CONFIG, &op,
+ sizeof(struct sec_accel_config));
+
+ writel(SRAM_CONFIG, cpg->reg + SEC_ACCEL_DESC_P0);
+ /* GO */
+ writel(SEC_CMD_EN_SEC_ACCL0, cpg->reg + SEC_ACCEL_CMD);
+
+ /*
+ * XXX: add timer if the interrupt does not occur for some mystery
+ * reason
+ */
+}
+
+static void mv_crypto_algo_completion(void)
+{
+ struct ablkcipher_request *req = cpg->cur_req;
+ struct mv_req_ctx *req_ctx = ablkcipher_request_ctx(req);
+
+ if (req_ctx->op != COP_AES_CBC)
+ return ;
+
+ memcpy(req->info, cpg->sram + SRAM_DATA_IV_BUF, 16);
+}
+
+static void dequeue_complete_req(void)
+{
+ struct ablkcipher_request *req = cpg->cur_req;
+ void *buf;
+ int ret;
+
+ cpg->p.total_req_bytes += cpg->p.crypt_len;
+ do {
+ int dst_copy;
+
+ if (!cpg->p.sg_dst_left) {
+ ret = sg_miter_next(&cpg->p.dst_sg_it);
+ BUG_ON(!ret);
+ cpg->p.sg_dst_left = cpg->p.dst_sg_it.length;
+ cpg->p.dst_start = 0;
+ }
+
+ buf = cpg->p.dst_sg_it.addr;
+ buf += cpg->p.dst_start;
+
+ dst_copy = min(cpg->p.crypt_len, cpg->p.sg_dst_left);
+
+ memcpy(buf, cpg->sram + SRAM_DATA_OUT_START, dst_copy);
+
+ cpg->p.sg_dst_left -= dst_copy;
+ cpg->p.crypt_len -= dst_copy;
+ cpg->p.dst_start += dst_copy;
+ } while (cpg->p.crypt_len > 0);
+
+ BUG_ON(cpg->eng_st != ENGINE_W_DEQUEUE);
+ if (cpg->p.total_req_bytes < req->nbytes) {
+ /* process next scatter list entry */
+ cpg->eng_st = ENGINE_BUSY;
+ mv_process_current_q(0);
+ } else {
+ sg_miter_stop(&cpg->p.src_sg_it);
+ sg_miter_stop(&cpg->p.dst_sg_it);
+ mv_crypto_algo_completion();
+ cpg->eng_st = ENGINE_IDLE;
+ req->base.complete(&req->base, 0);
+ }
+}
+
+static int count_sgs(struct scatterlist *sl, unsigned int total_bytes)
+{
+ int i = 0;
+
+ do {
+ total_bytes -= sl[i].length;
+ i++;
+
+ } while (total_bytes > 0);
+
+ return i;
+}
+
+static void mv_enqueue_new_req(struct ablkcipher_request *req)
+{
+ int num_sgs;
+
+ cpg->cur_req = req;
+ memset(&cpg->p, 0, sizeof(struct req_progress));
+
+ num_sgs = count_sgs(req->src, req->nbytes);
+ sg_miter_start(&cpg->p.src_sg_it, req->src, num_sgs, SG_MITER_FROM_SG);
+
+ num_sgs = count_sgs(req->dst, req->nbytes);
+ sg_miter_start(&cpg->p.dst_sg_it, req->dst, num_sgs, SG_MITER_TO_SG);
+ mv_process_current_q(1);
+}
+
+static int queue_manag(void *data)
+{
+ cpg->eng_st = ENGINE_IDLE;
+ do {
+ struct ablkcipher_request *req;
+ struct crypto_async_request *async_req = NULL;
+ struct crypto_async_request *backlog;
+
+ __set_current_state(TASK_INTERRUPTIBLE);
+
+ if (cpg->eng_st == ENGINE_W_DEQUEUE)
+ dequeue_complete_req();
+
+ spin_lock_irq(&cpg->lock);
+ if (cpg->eng_st == ENGINE_IDLE) {
+ backlog = crypto_get_backlog(&cpg->queue);
+ async_req = crypto_dequeue_request(&cpg->queue);
+ if (async_req) {
+ BUG_ON(cpg->eng_st != ENGINE_IDLE);
+ cpg->eng_st = ENGINE_BUSY;
+ }
+ }
+ spin_unlock_irq(&cpg->lock);
+
+ if (backlog) {
+ backlog->complete(backlog, -EINPROGRESS);
+ backlog = NULL;
+ }
+
+ if (async_req) {
+ req = container_of(async_req,
+ struct ablkcipher_request, base);
+ mv_enqueue_new_req(req);
+ async_req = NULL;
+ }
+
+ schedule();
+
+ } while (!kthread_should_stop());
+ return 0;
+}
+
+static int mv_handle_req(struct ablkcipher_request *req)
+{
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&cpg->lock, flags);
+ ret = ablkcipher_enqueue_request(&cpg->queue, req);
+ spin_unlock_irqrestore(&cpg->lock, flags);
+ wake_up_process(cpg->queue_th);
+ return ret;
+}
+
+static int mv_enc_aes_ecb(struct ablkcipher_request *req)
+{
+ struct mv_req_ctx *req_ctx = ablkcipher_request_ctx(req);
+
+ req_ctx->op = COP_AES_ECB;
+ req_ctx->decrypt = 0;
+
+ return mv_handle_req(req);
+}
+
+static int mv_dec_aes_ecb(struct ablkcipher_request *req)
+{
+ struct mv_ctx *ctx = crypto_tfm_ctx(req->base.tfm);
+ struct mv_req_ctx *req_ctx = ablkcipher_request_ctx(req);
+
+ req_ctx->op = COP_AES_ECB;
+ req_ctx->decrypt = 1;
+
+ compute_aes_dec_key(ctx);
+ return mv_handle_req(req);
+}
+
+static int mv_enc_aes_cbc(struct ablkcipher_request *req)
+{
+ struct mv_req_ctx *req_ctx = ablkcipher_request_ctx(req);
+
+ req_ctx->op = COP_AES_CBC;
+ req_ctx->decrypt = 0;
+
+ return mv_handle_req(req);
+}
+
+static int mv_dec_aes_cbc(struct ablkcipher_request *req)
+{
+ struct mv_ctx *ctx = crypto_tfm_ctx(req->base.tfm);
+ struct mv_req_ctx *req_ctx = ablkcipher_request_ctx(req);
+
+ req_ctx->op = COP_AES_CBC;
+ req_ctx->decrypt = 1;
+
+ compute_aes_dec_key(ctx);
+ return mv_handle_req(req);
+}
+
+static int mv_cra_init(struct crypto_tfm *tfm)
+{
+ tfm->crt_ablkcipher.reqsize = sizeof(struct mv_req_ctx);
+ return 0;
+}
+
+irqreturn_t crypto_int(int irq, void *priv)
+{
+ u32 val;
+
+ val = readl(cpg->reg + SEC_ACCEL_INT_STATUS);
+ if (!(val & SEC_INT_ACCEL0_DONE))
+ return IRQ_NONE;
+
+ val &= ~SEC_INT_ACCEL0_DONE;
+ writel(val, cpg->reg + FPGA_INT_STATUS);
+ writel(val, cpg->reg + SEC_ACCEL_INT_STATUS);
+ BUG_ON(cpg->eng_st != ENGINE_BUSY);
+ cpg->eng_st = ENGINE_W_DEQUEUE;
+ wake_up_process(cpg->queue_th);
+ return IRQ_HANDLED;
+}
+
+struct crypto_alg mv_aes_alg_ecb = {
+ .cra_name = "ecb(aes)",
+ .cra_driver_name = "mv-ecb-aes",
+ .cra_priority = 300,
+ .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
+ .cra_blocksize = 16,
+ .cra_ctxsize = sizeof(struct mv_ctx),
+ .cra_alignmask = 0,
+ .cra_type = &crypto_ablkcipher_type,
+ .cra_module = THIS_MODULE,
+ .cra_init = mv_cra_init,
+ .cra_u = {
+ .ablkcipher = {
+ .min_keysize = AES_MIN_KEY_SIZE,
+ .max_keysize = AES_MAX_KEY_SIZE,
+ .setkey = mv_setkey_aes,
+ .encrypt = mv_enc_aes_ecb,
+ .decrypt = mv_dec_aes_ecb,
+ },
+ },
+};
+
+struct crypto_alg mv_aes_alg_cbc = {
+ .cra_name = "cbc(aes)",
+ .cra_driver_name = "mv-cbc-aes",
+ .cra_priority = 300,
+ .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
+ .cra_blocksize = AES_BLOCK_SIZE,
+ .cra_ctxsize = sizeof(struct mv_ctx),
+ .cra_alignmask = 0,
+ .cra_type = &crypto_ablkcipher_type,
+ .cra_module = THIS_MODULE,
+ .cra_init = mv_cra_init,
+ .cra_u = {
+ .ablkcipher = {
+ .ivsize = AES_BLOCK_SIZE,
+ .min_keysize = AES_MIN_KEY_SIZE,
+ .max_keysize = AES_MAX_KEY_SIZE,
+ .setkey = mv_setkey_aes,
+ .encrypt = mv_enc_aes_cbc,
+ .decrypt = mv_dec_aes_cbc,
+ },
+ },
+};
+
+static int mv_probe(struct platform_device *pdev)
+{
+ struct crypto_priv *cp;
+ struct resource *res;
+ int irq;
+ int ret;
+
+ if (cpg) {
+ printk(KERN_ERR "Second crypto dev?\n");
+ return -EEXIST;
+ }
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "regs");
+ if (!res)
+ return -ENXIO;
+
+ cp = kzalloc(sizeof(*cp), GFP_KERNEL);
+ if (!cp)
+ return -ENOMEM;
+
+ spin_lock_init(&cp->lock);
+ crypto_init_queue(&cp->queue, 50);
+ cp->reg = ioremap(res->start, res->end - res->start + 1);
+ if (!cp->reg) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "sram");
+ if (!res) {
+ ret = -ENXIO;
+ goto err_unmap_reg;
+ }
+ cp->sram_size = res->end - res->start + 1;
+ cp->max_req_size = cp->sram_size - SRAM_CFG_SPACE;
+ cp->sram = ioremap(res->start, cp->sram_size);
+ if (!cp->sram) {
+ ret = -ENOMEM;
+ goto err_unmap_reg;
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0 || irq == NO_IRQ) {
+ ret = irq;
+ goto err_unmap_sram;
+ }
+ cp->irq = irq;
+
+ platform_set_drvdata(pdev, cp);
+ cpg = cp;
+
+ cp->queue_th = kthread_run(queue_manag, cp, "mv_crypto");
+ if (IS_ERR(cp->queue_th)) {
+ ret = PTR_ERR(cp->queue_th);
+ goto err_thread;
+ }
+
+ ret = request_irq(irq, crypto_int, IRQF_DISABLED, dev_name(&pdev->dev),
+ cp);
+ if (ret)
+ goto err_unmap_sram;
+
+ writel(SEC_INT_ACCEL0_DONE, cpg->reg + SEC_ACCEL_INT_MASK);
+ writel(SEC_CFG_STOP_DIG_ERR, cpg->reg + SEC_ACCEL_CFG);
+
+ ret = crypto_register_alg(&mv_aes_alg_ecb);
+ if (ret)
+ goto err_reg;
+
+ ret = crypto_register_alg(&mv_aes_alg_cbc);
+ if (ret)
+ goto err_unreg_ecb;
+ return 0;
+err_unreg_ecb:
+ crypto_unregister_alg(&mv_aes_alg_ecb);
+err_thread:
+ free_irq(irq, cp);
+err_reg:
+ kthread_stop(cp->queue_th);
+err_unmap_sram:
+ iounmap(cp->sram);
+err_unmap_reg:
+ iounmap(cp->reg);
+err:
+ kfree(cp);
+ cpg = NULL;
+ platform_set_drvdata(pdev, NULL);
+ return ret;
+}
+
+static int mv_remove(struct platform_device *pdev)
+{
+ struct crypto_priv *cp = platform_get_drvdata(pdev);
+
+ crypto_unregister_alg(&mv_aes_alg_ecb);
+ crypto_unregister_alg(&mv_aes_alg_cbc);
+ kthread_stop(cp->queue_th);
+ free_irq(cp->irq, cp);
+ memset(cp->sram, 0, cp->sram_size);
+ iounmap(cp->sram);
+ iounmap(cp->reg);
+ kfree(cp);
+ cpg = NULL;
+ return 0;
+}
+
+static struct platform_driver marvell_crypto = {
+ .probe = mv_probe,
+ .remove = mv_remove,
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "mv_crypto",
+ },
+};
+MODULE_ALIAS("platform:mv_crypto");
+
+static int __init mv_crypto_init(void)
+{
+ return platform_driver_register(&marvell_crypto);
+}
+module_init(mv_crypto_init);
+
+static void __exit mv_crypto_exit(void)
+{
+ platform_driver_unregister(&marvell_crypto);
+}
+module_exit(mv_crypto_exit);
+
+MODULE_AUTHOR("Sebastian Andrzej Siewior <sebastian@breakpoint.cc>");
+MODULE_DESCRIPTION("Support for Marvell's cryptographic engine");
+MODULE_LICENSE("GPL");