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-rw-r--r--drivers/crypto/sahara.c1070
1 files changed, 1070 insertions, 0 deletions
diff --git a/drivers/crypto/sahara.c b/drivers/crypto/sahara.c
new file mode 100644
index 0000000..a97bb6c
--- /dev/null
+++ b/drivers/crypto/sahara.c
@@ -0,0 +1,1070 @@
+/*
+ * Cryptographic API.
+ *
+ * Support for SAHARA cryptographic accelerator.
+ *
+ * Copyright (c) 2013 Vista Silicon S.L.
+ * Author: Javier Martin <javier.martin@vista-silicon.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ *
+ * Based on omap-aes.c and tegra-aes.c
+ */
+
+#include <crypto/algapi.h>
+#include <crypto/aes.h>
+
+#include <linux/clk.h>
+#include <linux/crypto.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
+#define SAHARA_NAME "sahara"
+#define SAHARA_VERSION_3 3
+#define SAHARA_TIMEOUT_MS 1000
+#define SAHARA_MAX_HW_DESC 2
+#define SAHARA_MAX_HW_LINK 20
+
+#define FLAGS_MODE_MASK 0x000f
+#define FLAGS_ENCRYPT BIT(0)
+#define FLAGS_CBC BIT(1)
+#define FLAGS_NEW_KEY BIT(3)
+#define FLAGS_BUSY 4
+
+#define SAHARA_HDR_BASE 0x00800000
+#define SAHARA_HDR_SKHA_ALG_AES 0
+#define SAHARA_HDR_SKHA_OP_ENC (1 << 2)
+#define SAHARA_HDR_SKHA_MODE_ECB (0 << 3)
+#define SAHARA_HDR_SKHA_MODE_CBC (1 << 3)
+#define SAHARA_HDR_FORM_DATA (5 << 16)
+#define SAHARA_HDR_FORM_KEY (8 << 16)
+#define SAHARA_HDR_LLO (1 << 24)
+#define SAHARA_HDR_CHA_SKHA (1 << 28)
+#define SAHARA_HDR_CHA_MDHA (2 << 28)
+#define SAHARA_HDR_PARITY_BIT (1 << 31)
+
+/* SAHARA can only process one request at a time */
+#define SAHARA_QUEUE_LENGTH 1
+
+#define SAHARA_REG_VERSION 0x00
+#define SAHARA_REG_DAR 0x04
+#define SAHARA_REG_CONTROL 0x08
+#define SAHARA_CONTROL_SET_THROTTLE(x) (((x) & 0xff) << 24)
+#define SAHARA_CONTROL_SET_MAXBURST(x) (((x) & 0xff) << 16)
+#define SAHARA_CONTROL_RNG_AUTORSD (1 << 7)
+#define SAHARA_CONTROL_ENABLE_INT (1 << 4)
+#define SAHARA_REG_CMD 0x0C
+#define SAHARA_CMD_RESET (1 << 0)
+#define SAHARA_CMD_CLEAR_INT (1 << 8)
+#define SAHARA_CMD_CLEAR_ERR (1 << 9)
+#define SAHARA_CMD_SINGLE_STEP (1 << 10)
+#define SAHARA_CMD_MODE_BATCH (1 << 16)
+#define SAHARA_CMD_MODE_DEBUG (1 << 18)
+#define SAHARA_REG_STATUS 0x10
+#define SAHARA_STATUS_GET_STATE(x) ((x) & 0x7)
+#define SAHARA_STATE_IDLE 0
+#define SAHARA_STATE_BUSY 1
+#define SAHARA_STATE_ERR 2
+#define SAHARA_STATE_FAULT 3
+#define SAHARA_STATE_COMPLETE 4
+#define SAHARA_STATE_COMP_FLAG (1 << 2)
+#define SAHARA_STATUS_DAR_FULL (1 << 3)
+#define SAHARA_STATUS_ERROR (1 << 4)
+#define SAHARA_STATUS_SECURE (1 << 5)
+#define SAHARA_STATUS_FAIL (1 << 6)
+#define SAHARA_STATUS_INIT (1 << 7)
+#define SAHARA_STATUS_RNG_RESEED (1 << 8)
+#define SAHARA_STATUS_ACTIVE_RNG (1 << 9)
+#define SAHARA_STATUS_ACTIVE_MDHA (1 << 10)
+#define SAHARA_STATUS_ACTIVE_SKHA (1 << 11)
+#define SAHARA_STATUS_MODE_BATCH (1 << 16)
+#define SAHARA_STATUS_MODE_DEDICATED (1 << 17)
+#define SAHARA_STATUS_MODE_DEBUG (1 << 18)
+#define SAHARA_STATUS_GET_ISTATE(x) (((x) >> 24) & 0xff)
+#define SAHARA_REG_ERRSTATUS 0x14
+#define SAHARA_ERRSTATUS_GET_SOURCE(x) ((x) & 0xf)
+#define SAHARA_ERRSOURCE_CHA 14
+#define SAHARA_ERRSOURCE_DMA 15
+#define SAHARA_ERRSTATUS_DMA_DIR (1 << 8)
+#define SAHARA_ERRSTATUS_GET_DMASZ(x)(((x) >> 9) & 0x3)
+#define SAHARA_ERRSTATUS_GET_DMASRC(x) (((x) >> 13) & 0x7)
+#define SAHARA_ERRSTATUS_GET_CHASRC(x) (((x) >> 16) & 0xfff)
+#define SAHARA_ERRSTATUS_GET_CHAERR(x) (((x) >> 28) & 0x3)
+#define SAHARA_REG_FADDR 0x18
+#define SAHARA_REG_CDAR 0x1C
+#define SAHARA_REG_IDAR 0x20
+
+struct sahara_hw_desc {
+ u32 hdr;
+ u32 len1;
+ dma_addr_t p1;
+ u32 len2;
+ dma_addr_t p2;
+ dma_addr_t next;
+};
+
+struct sahara_hw_link {
+ u32 len;
+ dma_addr_t p;
+ dma_addr_t next;
+};
+
+struct sahara_ctx {
+ struct sahara_dev *dev;
+ unsigned long flags;
+ int keylen;
+ u8 key[AES_KEYSIZE_128];
+ struct crypto_ablkcipher *fallback;
+};
+
+struct sahara_aes_reqctx {
+ unsigned long mode;
+};
+
+struct sahara_dev {
+ struct device *device;
+ void __iomem *regs_base;
+ struct clk *clk_ipg;
+ struct clk *clk_ahb;
+
+ struct sahara_ctx *ctx;
+ spinlock_t lock;
+ struct crypto_queue queue;
+ unsigned long flags;
+
+ struct tasklet_struct done_task;
+ struct tasklet_struct queue_task;
+
+ struct sahara_hw_desc *hw_desc[SAHARA_MAX_HW_DESC];
+ dma_addr_t hw_phys_desc[SAHARA_MAX_HW_DESC];
+
+ u8 *key_base;
+ dma_addr_t key_phys_base;
+
+ u8 *iv_base;
+ dma_addr_t iv_phys_base;
+
+ struct sahara_hw_link *hw_link[SAHARA_MAX_HW_LINK];
+ dma_addr_t hw_phys_link[SAHARA_MAX_HW_LINK];
+
+ struct ablkcipher_request *req;
+ size_t total;
+ struct scatterlist *in_sg;
+ unsigned int nb_in_sg;
+ struct scatterlist *out_sg;
+ unsigned int nb_out_sg;
+
+ u32 error;
+ struct timer_list watchdog;
+};
+
+static struct sahara_dev *dev_ptr;
+
+static inline void sahara_write(struct sahara_dev *dev, u32 data, u32 reg)
+{
+ writel(data, dev->regs_base + reg);
+}
+
+static inline unsigned int sahara_read(struct sahara_dev *dev, u32 reg)
+{
+ return readl(dev->regs_base + reg);
+}
+
+static u32 sahara_aes_key_hdr(struct sahara_dev *dev)
+{
+ u32 hdr = SAHARA_HDR_BASE | SAHARA_HDR_SKHA_ALG_AES |
+ SAHARA_HDR_FORM_KEY | SAHARA_HDR_LLO |
+ SAHARA_HDR_CHA_SKHA | SAHARA_HDR_PARITY_BIT;
+
+ if (dev->flags & FLAGS_CBC) {
+ hdr |= SAHARA_HDR_SKHA_MODE_CBC;
+ hdr ^= SAHARA_HDR_PARITY_BIT;
+ }
+
+ if (dev->flags & FLAGS_ENCRYPT) {
+ hdr |= SAHARA_HDR_SKHA_OP_ENC;
+ hdr ^= SAHARA_HDR_PARITY_BIT;
+ }
+
+ return hdr;
+}
+
+static u32 sahara_aes_data_link_hdr(struct sahara_dev *dev)
+{
+ return SAHARA_HDR_BASE | SAHARA_HDR_FORM_DATA |
+ SAHARA_HDR_CHA_SKHA | SAHARA_HDR_PARITY_BIT;
+}
+
+static int sahara_sg_length(struct scatterlist *sg,
+ unsigned int total)
+{
+ int sg_nb;
+ unsigned int len;
+ struct scatterlist *sg_list;
+
+ sg_nb = 0;
+ sg_list = sg;
+
+ while (total) {
+ len = min(sg_list->length, total);
+
+ sg_nb++;
+ total -= len;
+
+ sg_list = sg_next(sg_list);
+ if (!sg_list)
+ total = 0;
+ }
+
+ return sg_nb;
+}
+
+static char *sahara_err_src[16] = {
+ "No error",
+ "Header error",
+ "Descriptor length error",
+ "Descriptor length or pointer error",
+ "Link length error",
+ "Link pointer error",
+ "Input buffer error",
+ "Output buffer error",
+ "Output buffer starvation",
+ "Internal state fault",
+ "General descriptor problem",
+ "Reserved",
+ "Descriptor address error",
+ "Link address error",
+ "CHA error",
+ "DMA error"
+};
+
+static char *sahara_err_dmasize[4] = {
+ "Byte transfer",
+ "Half-word transfer",
+ "Word transfer",
+ "Reserved"
+};
+
+static char *sahara_err_dmasrc[8] = {
+ "No error",
+ "AHB bus error",
+ "Internal IP bus error",
+ "Parity error",
+ "DMA crosses 256 byte boundary",
+ "DMA is busy",
+ "Reserved",
+ "DMA HW error"
+};
+
+static char *sahara_cha_errsrc[12] = {
+ "Input buffer non-empty",
+ "Illegal address",
+ "Illegal mode",
+ "Illegal data size",
+ "Illegal key size",
+ "Write during processing",
+ "CTX read during processing",
+ "HW error",
+ "Input buffer disabled/underflow",
+ "Output buffer disabled/overflow",
+ "DES key parity error",
+ "Reserved"
+};
+
+static char *sahara_cha_err[4] = { "No error", "SKHA", "MDHA", "RNG" };
+
+static void sahara_decode_error(struct sahara_dev *dev, unsigned int error)
+{
+ u8 source = SAHARA_ERRSTATUS_GET_SOURCE(error);
+ u16 chasrc = ffs(SAHARA_ERRSTATUS_GET_CHASRC(error));
+
+ dev_err(dev->device, "%s: Error Register = 0x%08x\n", __func__, error);
+
+ dev_err(dev->device, " - %s.\n", sahara_err_src[source]);
+
+ if (source == SAHARA_ERRSOURCE_DMA) {
+ if (error & SAHARA_ERRSTATUS_DMA_DIR)
+ dev_err(dev->device, " * DMA read.\n");
+ else
+ dev_err(dev->device, " * DMA write.\n");
+
+ dev_err(dev->device, " * %s.\n",
+ sahara_err_dmasize[SAHARA_ERRSTATUS_GET_DMASZ(error)]);
+ dev_err(dev->device, " * %s.\n",
+ sahara_err_dmasrc[SAHARA_ERRSTATUS_GET_DMASRC(error)]);
+ } else if (source == SAHARA_ERRSOURCE_CHA) {
+ dev_err(dev->device, " * %s.\n",
+ sahara_cha_errsrc[chasrc]);
+ dev_err(dev->device, " * %s.\n",
+ sahara_cha_err[SAHARA_ERRSTATUS_GET_CHAERR(error)]);
+ }
+ dev_err(dev->device, "\n");
+}
+
+static char *sahara_state[4] = { "Idle", "Busy", "Error", "HW Fault" };
+
+static void sahara_decode_status(struct sahara_dev *dev, unsigned int status)
+{
+ u8 state;
+
+ if (!IS_ENABLED(DEBUG))
+ return;
+
+ state = SAHARA_STATUS_GET_STATE(status);
+
+ dev_dbg(dev->device, "%s: Status Register = 0x%08x\n",
+ __func__, status);
+
+ dev_dbg(dev->device, " - State = %d:\n", state);
+ if (state & SAHARA_STATE_COMP_FLAG)
+ dev_dbg(dev->device, " * Descriptor completed. IRQ pending.\n");
+
+ dev_dbg(dev->device, " * %s.\n",
+ sahara_state[state & ~SAHARA_STATE_COMP_FLAG]);
+
+ if (status & SAHARA_STATUS_DAR_FULL)
+ dev_dbg(dev->device, " - DAR Full.\n");
+ if (status & SAHARA_STATUS_ERROR)
+ dev_dbg(dev->device, " - Error.\n");
+ if (status & SAHARA_STATUS_SECURE)
+ dev_dbg(dev->device, " - Secure.\n");
+ if (status & SAHARA_STATUS_FAIL)
+ dev_dbg(dev->device, " - Fail.\n");
+ if (status & SAHARA_STATUS_RNG_RESEED)
+ dev_dbg(dev->device, " - RNG Reseed Request.\n");
+ if (status & SAHARA_STATUS_ACTIVE_RNG)
+ dev_dbg(dev->device, " - RNG Active.\n");
+ if (status & SAHARA_STATUS_ACTIVE_MDHA)
+ dev_dbg(dev->device, " - MDHA Active.\n");
+ if (status & SAHARA_STATUS_ACTIVE_SKHA)
+ dev_dbg(dev->device, " - SKHA Active.\n");
+
+ if (status & SAHARA_STATUS_MODE_BATCH)
+ dev_dbg(dev->device, " - Batch Mode.\n");
+ else if (status & SAHARA_STATUS_MODE_DEDICATED)
+ dev_dbg(dev->device, " - Decidated Mode.\n");
+ else if (status & SAHARA_STATUS_MODE_DEBUG)
+ dev_dbg(dev->device, " - Debug Mode.\n");
+
+ dev_dbg(dev->device, " - Internal state = 0x%02x\n",
+ SAHARA_STATUS_GET_ISTATE(status));
+
+ dev_dbg(dev->device, "Current DAR: 0x%08x\n",
+ sahara_read(dev, SAHARA_REG_CDAR));
+ dev_dbg(dev->device, "Initial DAR: 0x%08x\n\n",
+ sahara_read(dev, SAHARA_REG_IDAR));
+}
+
+static void sahara_dump_descriptors(struct sahara_dev *dev)
+{
+ int i;
+
+ if (!IS_ENABLED(DEBUG))
+ return;
+
+ for (i = 0; i < SAHARA_MAX_HW_DESC; i++) {
+ dev_dbg(dev->device, "Descriptor (%d) (0x%08x):\n",
+ i, dev->hw_phys_desc[i]);
+ dev_dbg(dev->device, "\thdr = 0x%08x\n", dev->hw_desc[i]->hdr);
+ dev_dbg(dev->device, "\tlen1 = %u\n", dev->hw_desc[i]->len1);
+ dev_dbg(dev->device, "\tp1 = 0x%08x\n", dev->hw_desc[i]->p1);
+ dev_dbg(dev->device, "\tlen2 = %u\n", dev->hw_desc[i]->len2);
+ dev_dbg(dev->device, "\tp2 = 0x%08x\n", dev->hw_desc[i]->p2);
+ dev_dbg(dev->device, "\tnext = 0x%08x\n",
+ dev->hw_desc[i]->next);
+ }
+ dev_dbg(dev->device, "\n");
+}
+
+static void sahara_dump_links(struct sahara_dev *dev)
+{
+ int i;
+
+ if (!IS_ENABLED(DEBUG))
+ return;
+
+ for (i = 0; i < SAHARA_MAX_HW_LINK; i++) {
+ dev_dbg(dev->device, "Link (%d) (0x%08x):\n",
+ i, dev->hw_phys_link[i]);
+ dev_dbg(dev->device, "\tlen = %u\n", dev->hw_link[i]->len);
+ dev_dbg(dev->device, "\tp = 0x%08x\n", dev->hw_link[i]->p);
+ dev_dbg(dev->device, "\tnext = 0x%08x\n",
+ dev->hw_link[i]->next);
+ }
+ dev_dbg(dev->device, "\n");
+}
+
+static void sahara_aes_done_task(unsigned long data)
+{
+ struct sahara_dev *dev = (struct sahara_dev *)data;
+
+ dma_unmap_sg(dev->device, dev->out_sg, dev->nb_out_sg,
+ DMA_TO_DEVICE);
+ dma_unmap_sg(dev->device, dev->in_sg, dev->nb_in_sg,
+ DMA_FROM_DEVICE);
+
+ spin_lock(&dev->lock);
+ clear_bit(FLAGS_BUSY, &dev->flags);
+ spin_unlock(&dev->lock);
+
+ dev->req->base.complete(&dev->req->base, dev->error);
+}
+
+void sahara_watchdog(unsigned long data)
+{
+ struct sahara_dev *dev = (struct sahara_dev *)data;
+ unsigned int err = sahara_read(dev, SAHARA_REG_ERRSTATUS);
+ unsigned int stat = sahara_read(dev, SAHARA_REG_STATUS);
+
+ sahara_decode_status(dev, stat);
+ sahara_decode_error(dev, err);
+ dev->error = -ETIMEDOUT;
+ sahara_aes_done_task(data);
+}
+
+static int sahara_hw_descriptor_create(struct sahara_dev *dev)
+{
+ struct sahara_ctx *ctx = dev->ctx;
+ struct scatterlist *sg;
+ int ret;
+ int i, j;
+
+ /* Copy new key if necessary */
+ if (ctx->flags & FLAGS_NEW_KEY) {
+ memcpy(dev->key_base, ctx->key, ctx->keylen);
+ ctx->flags &= ~FLAGS_NEW_KEY;
+
+ if (dev->flags & FLAGS_CBC) {
+ dev->hw_desc[0]->len1 = AES_BLOCK_SIZE;
+ dev->hw_desc[0]->p1 = dev->iv_phys_base;
+ } else {
+ dev->hw_desc[0]->len1 = 0;
+ dev->hw_desc[0]->p1 = 0;
+ }
+ dev->hw_desc[0]->len2 = ctx->keylen;
+ dev->hw_desc[0]->p2 = dev->key_phys_base;
+ dev->hw_desc[0]->next = dev->hw_phys_desc[1];
+ }
+ dev->hw_desc[0]->hdr = sahara_aes_key_hdr(dev);
+
+ dev->nb_in_sg = sahara_sg_length(dev->in_sg, dev->total);
+ dev->nb_out_sg = sahara_sg_length(dev->out_sg, dev->total);
+ if ((dev->nb_in_sg + dev->nb_out_sg) > SAHARA_MAX_HW_LINK) {
+ dev_err(dev->device, "not enough hw links (%d)\n",
+ dev->nb_in_sg + dev->nb_out_sg);
+ return -EINVAL;
+ }
+
+ ret = dma_map_sg(dev->device, dev->in_sg, dev->nb_in_sg,
+ DMA_TO_DEVICE);
+ if (ret != dev->nb_in_sg) {
+ dev_err(dev->device, "couldn't map in sg\n");
+ goto unmap_in;
+ }
+ ret = dma_map_sg(dev->device, dev->out_sg, dev->nb_out_sg,
+ DMA_FROM_DEVICE);
+ if (ret != dev->nb_out_sg) {
+ dev_err(dev->device, "couldn't map out sg\n");
+ goto unmap_out;
+ }
+
+ /* Create input links */
+ dev->hw_desc[1]->p1 = dev->hw_phys_link[0];
+ sg = dev->in_sg;
+ for (i = 0; i < dev->nb_in_sg; i++) {
+ dev->hw_link[i]->len = sg->length;
+ dev->hw_link[i]->p = sg->dma_address;
+ if (i == (dev->nb_in_sg - 1)) {
+ dev->hw_link[i]->next = 0;
+ } else {
+ dev->hw_link[i]->next = dev->hw_phys_link[i + 1];
+ sg = sg_next(sg);
+ }
+ }
+
+ /* Create output links */
+ dev->hw_desc[1]->p2 = dev->hw_phys_link[i];
+ sg = dev->out_sg;
+ for (j = i; j < dev->nb_out_sg + i; j++) {
+ dev->hw_link[j]->len = sg->length;
+ dev->hw_link[j]->p = sg->dma_address;
+ if (j == (dev->nb_out_sg + i - 1)) {
+ dev->hw_link[j]->next = 0;
+ } else {
+ dev->hw_link[j]->next = dev->hw_phys_link[j + 1];
+ sg = sg_next(sg);
+ }
+ }
+
+ /* Fill remaining fields of hw_desc[1] */
+ dev->hw_desc[1]->hdr = sahara_aes_data_link_hdr(dev);
+ dev->hw_desc[1]->len1 = dev->total;
+ dev->hw_desc[1]->len2 = dev->total;
+ dev->hw_desc[1]->next = 0;
+
+ sahara_dump_descriptors(dev);
+ sahara_dump_links(dev);
+
+ /* Start processing descriptor chain. */
+ mod_timer(&dev->watchdog,
+ jiffies + msecs_to_jiffies(SAHARA_TIMEOUT_MS));
+ sahara_write(dev, dev->hw_phys_desc[0], SAHARA_REG_DAR);
+
+ return 0;
+
+unmap_out:
+ dma_unmap_sg(dev->device, dev->out_sg, dev->nb_out_sg,
+ DMA_TO_DEVICE);
+unmap_in:
+ dma_unmap_sg(dev->device, dev->in_sg, dev->nb_in_sg,
+ DMA_FROM_DEVICE);
+
+ return -EINVAL;
+}
+
+static void sahara_aes_queue_task(unsigned long data)
+{
+ struct sahara_dev *dev = (struct sahara_dev *)data;
+ struct crypto_async_request *async_req, *backlog;
+ struct sahara_ctx *ctx;
+ struct sahara_aes_reqctx *rctx;
+ struct ablkcipher_request *req;
+ int ret;
+
+ spin_lock(&dev->lock);
+ backlog = crypto_get_backlog(&dev->queue);
+ async_req = crypto_dequeue_request(&dev->queue);
+ if (!async_req)
+ clear_bit(FLAGS_BUSY, &dev->flags);
+ spin_unlock(&dev->lock);
+
+ if (!async_req)
+ return;
+
+ if (backlog)
+ backlog->complete(backlog, -EINPROGRESS);
+
+ req = ablkcipher_request_cast(async_req);
+
+ /* Request is ready to be dispatched by the device */
+ dev_dbg(dev->device,
+ "dispatch request (nbytes=%d, src=%p, dst=%p)\n",
+ req->nbytes, req->src, req->dst);
+
+ /* assign new request to device */
+ dev->req = req;
+ dev->total = req->nbytes;
+ dev->in_sg = req->src;
+ dev->out_sg = req->dst;
+
+ rctx = ablkcipher_request_ctx(req);
+ ctx = crypto_ablkcipher_ctx(crypto_ablkcipher_reqtfm(req));
+ rctx->mode &= FLAGS_MODE_MASK;
+ dev->flags = (dev->flags & ~FLAGS_MODE_MASK) | rctx->mode;
+
+ if ((dev->flags & FLAGS_CBC) && req->info)
+ memcpy(dev->iv_base, req->info, AES_KEYSIZE_128);
+
+ /* assign new context to device */
+ ctx->dev = dev;
+ dev->ctx = ctx;
+
+ ret = sahara_hw_descriptor_create(dev);
+ if (ret < 0) {
+ spin_lock(&dev->lock);
+ clear_bit(FLAGS_BUSY, &dev->flags);
+ spin_unlock(&dev->lock);
+ dev->req->base.complete(&dev->req->base, ret);
+ }
+}
+
+static int sahara_aes_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
+ unsigned int keylen)
+{
+ struct sahara_ctx *ctx = crypto_ablkcipher_ctx(tfm);
+ int ret;
+
+ ctx->keylen = keylen;
+
+ /* SAHARA only supports 128bit keys */
+ if (keylen == AES_KEYSIZE_128) {
+ memcpy(ctx->key, key, keylen);
+ ctx->flags |= FLAGS_NEW_KEY;
+ return 0;
+ }
+
+ if (keylen != AES_KEYSIZE_128 &&
+ keylen != AES_KEYSIZE_192 && keylen != AES_KEYSIZE_256)
+ return -EINVAL;
+
+ /*
+ * The requested key size is not supported by HW, do a fallback.
+ */
+ ctx->fallback->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK;
+ ctx->fallback->base.crt_flags |=
+ (tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK);
+
+ ret = crypto_ablkcipher_setkey(ctx->fallback, key, keylen);
+ if (ret) {
+ struct crypto_tfm *tfm_aux = crypto_ablkcipher_tfm(tfm);
+
+ tfm_aux->crt_flags &= ~CRYPTO_TFM_RES_MASK;
+ tfm_aux->crt_flags |=
+ (ctx->fallback->base.crt_flags & CRYPTO_TFM_RES_MASK);
+ }
+ return ret;
+}
+
+static int sahara_aes_crypt(struct ablkcipher_request *req, unsigned long mode)
+{
+ struct sahara_ctx *ctx = crypto_ablkcipher_ctx(
+ crypto_ablkcipher_reqtfm(req));
+ struct sahara_aes_reqctx *rctx = ablkcipher_request_ctx(req);
+ struct sahara_dev *dev = dev_ptr;
+ int err = 0;
+ int busy;
+
+ dev_dbg(dev->device, "nbytes: %d, enc: %d, cbc: %d\n",
+ req->nbytes, !!(mode & FLAGS_ENCRYPT), !!(mode & FLAGS_CBC));
+
+ if (!IS_ALIGNED(req->nbytes, AES_BLOCK_SIZE)) {
+ dev_err(dev->device,
+ "request size is not exact amount of AES blocks\n");
+ return -EINVAL;
+ }
+
+ ctx->dev = dev;
+
+ rctx->mode = mode;
+ spin_lock_bh(&dev->lock);
+ err = ablkcipher_enqueue_request(&dev->queue, req);
+ busy = test_and_set_bit(FLAGS_BUSY, &dev->flags);
+ spin_unlock_bh(&dev->lock);
+
+ if (!busy)
+ tasklet_schedule(&dev->queue_task);
+
+ return err;
+}
+
+static int sahara_aes_ecb_encrypt(struct ablkcipher_request *req)
+{
+ struct crypto_tfm *tfm =
+ crypto_ablkcipher_tfm(crypto_ablkcipher_reqtfm(req));
+ struct sahara_ctx *ctx = crypto_ablkcipher_ctx(
+ crypto_ablkcipher_reqtfm(req));
+ int err;
+
+ if (unlikely(ctx->keylen != AES_KEYSIZE_128)) {
+ ablkcipher_request_set_tfm(req, ctx->fallback);
+ err = crypto_ablkcipher_encrypt(req);
+ ablkcipher_request_set_tfm(req, __crypto_ablkcipher_cast(tfm));
+ return err;
+ }
+
+ return sahara_aes_crypt(req, FLAGS_ENCRYPT);
+}
+
+static int sahara_aes_ecb_decrypt(struct ablkcipher_request *req)
+{
+ struct crypto_tfm *tfm =
+ crypto_ablkcipher_tfm(crypto_ablkcipher_reqtfm(req));
+ struct sahara_ctx *ctx = crypto_ablkcipher_ctx(
+ crypto_ablkcipher_reqtfm(req));
+ int err;
+
+ if (unlikely(ctx->keylen != AES_KEYSIZE_128)) {
+ ablkcipher_request_set_tfm(req, ctx->fallback);
+ err = crypto_ablkcipher_decrypt(req);
+ ablkcipher_request_set_tfm(req, __crypto_ablkcipher_cast(tfm));
+ return err;
+ }
+
+ return sahara_aes_crypt(req, 0);
+}
+
+static int sahara_aes_cbc_encrypt(struct ablkcipher_request *req)
+{
+ struct crypto_tfm *tfm =
+ crypto_ablkcipher_tfm(crypto_ablkcipher_reqtfm(req));
+ struct sahara_ctx *ctx = crypto_ablkcipher_ctx(
+ crypto_ablkcipher_reqtfm(req));
+ int err;
+
+ if (unlikely(ctx->keylen != AES_KEYSIZE_128)) {
+ ablkcipher_request_set_tfm(req, ctx->fallback);
+ err = crypto_ablkcipher_encrypt(req);
+ ablkcipher_request_set_tfm(req, __crypto_ablkcipher_cast(tfm));
+ return err;
+ }
+
+ return sahara_aes_crypt(req, FLAGS_ENCRYPT | FLAGS_CBC);
+}
+
+static int sahara_aes_cbc_decrypt(struct ablkcipher_request *req)
+{
+ struct crypto_tfm *tfm =
+ crypto_ablkcipher_tfm(crypto_ablkcipher_reqtfm(req));
+ struct sahara_ctx *ctx = crypto_ablkcipher_ctx(
+ crypto_ablkcipher_reqtfm(req));
+ int err;
+
+ if (unlikely(ctx->keylen != AES_KEYSIZE_128)) {
+ ablkcipher_request_set_tfm(req, ctx->fallback);
+ err = crypto_ablkcipher_decrypt(req);
+ ablkcipher_request_set_tfm(req, __crypto_ablkcipher_cast(tfm));
+ return err;
+ }
+
+ return sahara_aes_crypt(req, FLAGS_CBC);
+}
+
+static int sahara_aes_cra_init(struct crypto_tfm *tfm)
+{
+ const char *name = tfm->__crt_alg->cra_name;
+ struct sahara_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ ctx->fallback = crypto_alloc_ablkcipher(name, 0,
+ CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK);
+ if (IS_ERR(ctx->fallback)) {
+ pr_err("Error allocating fallback algo %s\n", name);
+ return PTR_ERR(ctx->fallback);
+ }
+
+ tfm->crt_ablkcipher.reqsize = sizeof(struct sahara_aes_reqctx);
+
+ return 0;
+}
+
+static void sahara_aes_cra_exit(struct crypto_tfm *tfm)
+{
+ struct sahara_ctx *ctx = crypto_tfm_ctx(tfm);
+
+ if (ctx->fallback)
+ crypto_free_ablkcipher(ctx->fallback);
+ ctx->fallback = NULL;
+}
+
+static struct crypto_alg aes_algs[] = {
+{
+ .cra_name = "ecb(aes)",
+ .cra_driver_name = "sahara-ecb-aes",
+ .cra_priority = 300,
+ .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER |
+ CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK,
+ .cra_blocksize = AES_BLOCK_SIZE,
+ .cra_ctxsize = sizeof(struct sahara_ctx),
+ .cra_alignmask = 0x0,
+ .cra_type = &crypto_ablkcipher_type,
+ .cra_module = THIS_MODULE,
+ .cra_init = sahara_aes_cra_init,
+ .cra_exit = sahara_aes_cra_exit,
+ .cra_u.ablkcipher = {
+ .min_keysize = AES_MIN_KEY_SIZE ,
+ .max_keysize = AES_MAX_KEY_SIZE,
+ .setkey = sahara_aes_setkey,
+ .encrypt = sahara_aes_ecb_encrypt,
+ .decrypt = sahara_aes_ecb_decrypt,
+ }
+}, {
+ .cra_name = "cbc(aes)",
+ .cra_driver_name = "sahara-cbc-aes",
+ .cra_priority = 300,
+ .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER |
+ CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK,
+ .cra_blocksize = AES_BLOCK_SIZE,
+ .cra_ctxsize = sizeof(struct sahara_ctx),
+ .cra_alignmask = 0x0,
+ .cra_type = &crypto_ablkcipher_type,
+ .cra_module = THIS_MODULE,
+ .cra_init = sahara_aes_cra_init,
+ .cra_exit = sahara_aes_cra_exit,
+ .cra_u.ablkcipher = {
+ .min_keysize = AES_MIN_KEY_SIZE ,
+ .max_keysize = AES_MAX_KEY_SIZE,
+ .ivsize = AES_BLOCK_SIZE,
+ .setkey = sahara_aes_setkey,
+ .encrypt = sahara_aes_cbc_encrypt,
+ .decrypt = sahara_aes_cbc_decrypt,
+ }
+}
+};
+
+static irqreturn_t sahara_irq_handler(int irq, void *data)
+{
+ struct sahara_dev *dev = (struct sahara_dev *)data;
+ unsigned int stat = sahara_read(dev, SAHARA_REG_STATUS);
+ unsigned int err = sahara_read(dev, SAHARA_REG_ERRSTATUS);
+
+ del_timer(&dev->watchdog);
+
+ sahara_write(dev, SAHARA_CMD_CLEAR_INT | SAHARA_CMD_CLEAR_ERR,
+ SAHARA_REG_CMD);
+
+ sahara_decode_status(dev, stat);
+
+ if (SAHARA_STATUS_GET_STATE(stat) == SAHARA_STATE_BUSY) {
+ return IRQ_NONE;
+ } else if (SAHARA_STATUS_GET_STATE(stat) == SAHARA_STATE_COMPLETE) {
+ dev->error = 0;
+ } else {
+ sahara_decode_error(dev, err);
+ dev->error = -EINVAL;
+ }
+
+ tasklet_schedule(&dev->done_task);
+
+ return IRQ_HANDLED;
+}
+
+
+static int sahara_register_algs(struct sahara_dev *dev)
+{
+ int err, i, j;
+
+ for (i = 0; i < ARRAY_SIZE(aes_algs); i++) {
+ INIT_LIST_HEAD(&aes_algs[i].cra_list);
+ err = crypto_register_alg(&aes_algs[i]);
+ if (err)
+ goto err_aes_algs;
+ }
+
+ return 0;
+
+err_aes_algs:
+ for (j = 0; j < i; j++)
+ crypto_unregister_alg(&aes_algs[j]);
+
+ return err;
+}
+
+static void sahara_unregister_algs(struct sahara_dev *dev)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(aes_algs); i++)
+ crypto_unregister_alg(&aes_algs[i]);
+}
+
+static struct platform_device_id sahara_platform_ids[] = {
+ { .name = "sahara-imx27" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(platform, sahara_platform_ids);
+
+static struct of_device_id sahara_dt_ids[] = {
+ { .compatible = "fsl,imx27-sahara" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(platform, sahara_dt_ids);
+
+static int sahara_probe(struct platform_device *pdev)
+{
+ struct sahara_dev *dev;
+ struct resource *res;
+ u32 version;
+ int irq;
+ int err;
+ int i;
+
+ dev = devm_kzalloc(&pdev->dev, sizeof(struct sahara_dev), GFP_KERNEL);
+ if (dev == NULL) {
+ dev_err(&pdev->dev, "unable to alloc data struct.\n");
+ return -ENOMEM;
+ }
+
+ dev->device = &pdev->dev;
+ platform_set_drvdata(pdev, dev);
+
+ /* Get the base address */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "failed to get memory region resource\n");
+ return -ENODEV;
+ }
+
+ if (devm_request_mem_region(&pdev->dev, res->start,
+ resource_size(res), SAHARA_NAME) == NULL) {
+ dev_err(&pdev->dev, "failed to request memory region\n");
+ return -ENOENT;
+ }
+ dev->regs_base = devm_ioremap(&pdev->dev, res->start,
+ resource_size(res));
+ if (!dev->regs_base) {
+ dev_err(&pdev->dev, "failed to ioremap address region\n");
+ return -ENOENT;
+ }
+
+ /* Get the IRQ */
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "failed to get irq resource\n");
+ return irq;
+ }
+
+ if (devm_request_irq(&pdev->dev, irq, sahara_irq_handler,
+ 0, SAHARA_NAME, dev) < 0) {
+ dev_err(&pdev->dev, "failed to request irq\n");
+ return -ENOENT;
+ }
+
+ /* clocks */
+ dev->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
+ if (IS_ERR(dev->clk_ipg)) {
+ dev_err(&pdev->dev, "Could not get ipg clock\n");
+ return PTR_ERR(dev->clk_ipg);
+ }
+
+ dev->clk_ahb = devm_clk_get(&pdev->dev, "ahb");
+ if (IS_ERR(dev->clk_ahb)) {
+ dev_err(&pdev->dev, "Could not get ahb clock\n");
+ return PTR_ERR(dev->clk_ahb);
+ }
+
+ /* Allocate HW descriptors */
+ dev->hw_desc[0] = dma_alloc_coherent(&pdev->dev,
+ SAHARA_MAX_HW_DESC * sizeof(struct sahara_hw_desc),
+ &dev->hw_phys_desc[0], GFP_KERNEL);
+ if (!dev->hw_desc[0]) {
+ dev_err(&pdev->dev, "Could not allocate hw descriptors\n");
+ return -ENOMEM;
+ }
+ dev->hw_desc[1] = dev->hw_desc[0] + 1;
+ dev->hw_phys_desc[1] = dev->hw_phys_desc[0] +
+ sizeof(struct sahara_hw_desc);
+
+ /* Allocate space for iv and key */
+ dev->key_base = dma_alloc_coherent(&pdev->dev, 2 * AES_KEYSIZE_128,
+ &dev->key_phys_base, GFP_KERNEL);
+ if (!dev->key_base) {
+ dev_err(&pdev->dev, "Could not allocate memory for key\n");
+ err = -ENOMEM;
+ goto err_key;
+ }
+ dev->iv_base = dev->key_base + AES_KEYSIZE_128;
+ dev->iv_phys_base = dev->key_phys_base + AES_KEYSIZE_128;
+
+ /* Allocate space for HW links */
+ dev->hw_link[0] = dma_alloc_coherent(&pdev->dev,
+ SAHARA_MAX_HW_LINK * sizeof(struct sahara_hw_link),
+ &dev->hw_phys_link[0], GFP_KERNEL);
+ if (!dev->hw_link) {
+ dev_err(&pdev->dev, "Could not allocate hw links\n");
+ err = -ENOMEM;
+ goto err_link;
+ }
+ for (i = 1; i < SAHARA_MAX_HW_LINK; i++) {
+ dev->hw_phys_link[i] = dev->hw_phys_link[i - 1] +
+ sizeof(struct sahara_hw_link);
+ dev->hw_link[i] = dev->hw_link[i - 1] + 1;
+ }
+
+ crypto_init_queue(&dev->queue, SAHARA_QUEUE_LENGTH);
+
+ dev_ptr = dev;
+
+ tasklet_init(&dev->queue_task, sahara_aes_queue_task,
+ (unsigned long)dev);
+ tasklet_init(&dev->done_task, sahara_aes_done_task,
+ (unsigned long)dev);
+
+ init_timer(&dev->watchdog);
+ dev->watchdog.function = &sahara_watchdog;
+ dev->watchdog.data = (unsigned long)dev;
+
+ clk_prepare_enable(dev->clk_ipg);
+ clk_prepare_enable(dev->clk_ahb);
+
+ version = sahara_read(dev, SAHARA_REG_VERSION);
+ if (version != SAHARA_VERSION_3) {
+ dev_err(&pdev->dev, "SAHARA version %d not supported\n",
+ version);
+ err = -ENODEV;
+ goto err_algs;
+ }
+
+ sahara_write(dev, SAHARA_CMD_RESET | SAHARA_CMD_MODE_BATCH,
+ SAHARA_REG_CMD);
+ sahara_write(dev, SAHARA_CONTROL_SET_THROTTLE(0) |
+ SAHARA_CONTROL_SET_MAXBURST(8) |
+ SAHARA_CONTROL_RNG_AUTORSD |
+ SAHARA_CONTROL_ENABLE_INT,
+ SAHARA_REG_CONTROL);
+
+ err = sahara_register_algs(dev);
+ if (err)
+ goto err_algs;
+
+ dev_info(&pdev->dev, "SAHARA version %d initialized\n", version);
+
+ return 0;
+
+err_algs:
+ dma_free_coherent(&pdev->dev,
+ SAHARA_MAX_HW_LINK * sizeof(struct sahara_hw_link),
+ dev->hw_link[0], dev->hw_phys_link[0]);
+ clk_disable_unprepare(dev->clk_ipg);
+ clk_disable_unprepare(dev->clk_ahb);
+ dev_ptr = NULL;
+err_link:
+ dma_free_coherent(&pdev->dev,
+ 2 * AES_KEYSIZE_128,
+ dev->key_base, dev->key_phys_base);
+err_key:
+ dma_free_coherent(&pdev->dev,
+ SAHARA_MAX_HW_DESC * sizeof(struct sahara_hw_desc),
+ dev->hw_desc[0], dev->hw_phys_desc[0]);
+
+ return err;
+}
+
+static int sahara_remove(struct platform_device *pdev)
+{
+ struct sahara_dev *dev = platform_get_drvdata(pdev);
+
+ dma_free_coherent(&pdev->dev,
+ SAHARA_MAX_HW_LINK * sizeof(struct sahara_hw_link),
+ dev->hw_link[0], dev->hw_phys_link[0]);
+ dma_free_coherent(&pdev->dev,
+ 2 * AES_KEYSIZE_128,
+ dev->key_base, dev->key_phys_base);
+ dma_free_coherent(&pdev->dev,
+ SAHARA_MAX_HW_DESC * sizeof(struct sahara_hw_desc),
+ dev->hw_desc[0], dev->hw_phys_desc[0]);
+
+ tasklet_kill(&dev->done_task);
+ tasklet_kill(&dev->queue_task);
+
+ sahara_unregister_algs(dev);
+
+ clk_disable_unprepare(dev->clk_ipg);
+ clk_disable_unprepare(dev->clk_ahb);
+
+ dev_ptr = NULL;
+
+ return 0;
+}
+
+static struct platform_driver sahara_driver = {
+ .probe = sahara_probe,
+ .remove = sahara_remove,
+ .driver = {
+ .name = SAHARA_NAME,
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(sahara_dt_ids),
+ },
+ .id_table = sahara_platform_ids,
+};
+
+module_platform_driver(sahara_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Javier Martin <javier.martin@vista-silicon.com>");
+MODULE_DESCRIPTION("SAHARA2 HW crypto accelerator");
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