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-rw-r--r--drivers/crypto/keembay/ocs-aes.c1489
1 files changed, 1489 insertions, 0 deletions
diff --git a/drivers/crypto/keembay/ocs-aes.c b/drivers/crypto/keembay/ocs-aes.c
new file mode 100644
index 000000000..be9f32fc8
--- /dev/null
+++ b/drivers/crypto/keembay/ocs-aes.c
@@ -0,0 +1,1489 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Intel Keem Bay OCS AES Crypto Driver.
+ *
+ * Copyright (C) 2018-2020 Intel Corporation
+ */
+
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/swab.h>
+
+#include <asm/byteorder.h>
+#include <asm/errno.h>
+
+#include <crypto/aes.h>
+#include <crypto/gcm.h>
+
+#include "ocs-aes.h"
+
+#define AES_COMMAND_OFFSET 0x0000
+#define AES_KEY_0_OFFSET 0x0004
+#define AES_KEY_1_OFFSET 0x0008
+#define AES_KEY_2_OFFSET 0x000C
+#define AES_KEY_3_OFFSET 0x0010
+#define AES_KEY_4_OFFSET 0x0014
+#define AES_KEY_5_OFFSET 0x0018
+#define AES_KEY_6_OFFSET 0x001C
+#define AES_KEY_7_OFFSET 0x0020
+#define AES_IV_0_OFFSET 0x0024
+#define AES_IV_1_OFFSET 0x0028
+#define AES_IV_2_OFFSET 0x002C
+#define AES_IV_3_OFFSET 0x0030
+#define AES_ACTIVE_OFFSET 0x0034
+#define AES_STATUS_OFFSET 0x0038
+#define AES_KEY_SIZE_OFFSET 0x0044
+#define AES_IER_OFFSET 0x0048
+#define AES_ISR_OFFSET 0x005C
+#define AES_MULTIPURPOSE1_0_OFFSET 0x0200
+#define AES_MULTIPURPOSE1_1_OFFSET 0x0204
+#define AES_MULTIPURPOSE1_2_OFFSET 0x0208
+#define AES_MULTIPURPOSE1_3_OFFSET 0x020C
+#define AES_MULTIPURPOSE2_0_OFFSET 0x0220
+#define AES_MULTIPURPOSE2_1_OFFSET 0x0224
+#define AES_MULTIPURPOSE2_2_OFFSET 0x0228
+#define AES_MULTIPURPOSE2_3_OFFSET 0x022C
+#define AES_BYTE_ORDER_CFG_OFFSET 0x02C0
+#define AES_TLEN_OFFSET 0x0300
+#define AES_T_MAC_0_OFFSET 0x0304
+#define AES_T_MAC_1_OFFSET 0x0308
+#define AES_T_MAC_2_OFFSET 0x030C
+#define AES_T_MAC_3_OFFSET 0x0310
+#define AES_PLEN_OFFSET 0x0314
+#define AES_A_DMA_SRC_ADDR_OFFSET 0x0400
+#define AES_A_DMA_DST_ADDR_OFFSET 0x0404
+#define AES_A_DMA_SRC_SIZE_OFFSET 0x0408
+#define AES_A_DMA_DST_SIZE_OFFSET 0x040C
+#define AES_A_DMA_DMA_MODE_OFFSET 0x0410
+#define AES_A_DMA_NEXT_SRC_DESCR_OFFSET 0x0418
+#define AES_A_DMA_NEXT_DST_DESCR_OFFSET 0x041C
+#define AES_A_DMA_WHILE_ACTIVE_MODE_OFFSET 0x0420
+#define AES_A_DMA_LOG_OFFSET 0x0424
+#define AES_A_DMA_STATUS_OFFSET 0x0428
+#define AES_A_DMA_PERF_CNTR_OFFSET 0x042C
+#define AES_A_DMA_MSI_ISR_OFFSET 0x0480
+#define AES_A_DMA_MSI_IER_OFFSET 0x0484
+#define AES_A_DMA_MSI_MASK_OFFSET 0x0488
+#define AES_A_DMA_INBUFFER_WRITE_FIFO_OFFSET 0x0600
+#define AES_A_DMA_OUTBUFFER_READ_FIFO_OFFSET 0x0700
+
+/*
+ * AES_A_DMA_DMA_MODE register.
+ * Default: 0x00000000.
+ * bit[31] ACTIVE
+ * This bit activates the DMA. When the DMA finishes, it resets
+ * this bit to zero.
+ * bit[30:26] Unused by this driver.
+ * bit[25] SRC_LINK_LIST_EN
+ * Source link list enable bit. When the linked list is terminated
+ * this bit is reset by the DMA.
+ * bit[24] DST_LINK_LIST_EN
+ * Destination link list enable bit. When the linked list is
+ * terminated this bit is reset by the DMA.
+ * bit[23:0] Unused by this driver.
+ */
+#define AES_A_DMA_DMA_MODE_ACTIVE BIT(31)
+#define AES_A_DMA_DMA_MODE_SRC_LINK_LIST_EN BIT(25)
+#define AES_A_DMA_DMA_MODE_DST_LINK_LIST_EN BIT(24)
+
+/*
+ * AES_ACTIVE register
+ * default 0x00000000
+ * bit[31:10] Reserved
+ * bit[9] LAST_ADATA
+ * bit[8] LAST_GCX
+ * bit[7:2] Reserved
+ * bit[1] TERMINATION
+ * bit[0] TRIGGER
+ */
+#define AES_ACTIVE_LAST_ADATA BIT(9)
+#define AES_ACTIVE_LAST_CCM_GCM BIT(8)
+#define AES_ACTIVE_TERMINATION BIT(1)
+#define AES_ACTIVE_TRIGGER BIT(0)
+
+#define AES_DISABLE_INT 0x00000000
+#define AES_DMA_CPD_ERR_INT BIT(8)
+#define AES_DMA_OUTBUF_RD_ERR_INT BIT(7)
+#define AES_DMA_OUTBUF_WR_ERR_INT BIT(6)
+#define AES_DMA_INBUF_RD_ERR_INT BIT(5)
+#define AES_DMA_INBUF_WR_ERR_INT BIT(4)
+#define AES_DMA_BAD_COMP_INT BIT(3)
+#define AES_DMA_SAI_INT BIT(2)
+#define AES_DMA_SRC_DONE_INT BIT(0)
+#define AES_COMPLETE_INT BIT(1)
+
+#define AES_DMA_MSI_MASK_CLEAR BIT(0)
+
+#define AES_128_BIT_KEY 0x00000000
+#define AES_256_BIT_KEY BIT(0)
+
+#define AES_DEACTIVATE_PERF_CNTR 0x00000000
+#define AES_ACTIVATE_PERF_CNTR BIT(0)
+
+#define AES_MAX_TAG_SIZE_U32 4
+
+#define OCS_LL_DMA_FLAG_TERMINATE BIT(31)
+
+/*
+ * There is an inconsistency in the documentation. This is documented as a
+ * 11-bit value, but it is actually 10-bits.
+ */
+#define AES_DMA_STATUS_INPUT_BUFFER_OCCUPANCY_MASK 0x3FF
+
+/*
+ * During CCM decrypt, the OCS block needs to finish processing the ciphertext
+ * before the tag is written. For 128-bit mode this required delay is 28 OCS
+ * clock cycles. For 256-bit mode it is 36 OCS clock cycles.
+ */
+#define CCM_DECRYPT_DELAY_TAG_CLK_COUNT 36UL
+
+/*
+ * During CCM decrypt there must be a delay of at least 42 OCS clock cycles
+ * between setting the TRIGGER bit in AES_ACTIVE and setting the LAST_CCM_GCM
+ * bit in the same register (as stated in the OCS databook)
+ */
+#define CCM_DECRYPT_DELAY_LAST_GCX_CLK_COUNT 42UL
+
+/* See RFC3610 section 2.2 */
+#define L_PRIME_MIN (1)
+#define L_PRIME_MAX (7)
+/*
+ * CCM IV format from RFC 3610 section 2.3
+ *
+ * Octet Number Contents
+ * ------------ ---------
+ * 0 Flags
+ * 1 ... 15-L Nonce N
+ * 16-L ... 15 Counter i
+ *
+ * Flags = L' = L - 1
+ */
+#define L_PRIME_IDX 0
+#define COUNTER_START(lprime) (16 - ((lprime) + 1))
+#define COUNTER_LEN(lprime) ((lprime) + 1)
+
+enum aes_counter_mode {
+ AES_CTR_M_NO_INC = 0,
+ AES_CTR_M_32_INC = 1,
+ AES_CTR_M_64_INC = 2,
+ AES_CTR_M_128_INC = 3,
+};
+
+/**
+ * struct ocs_dma_linked_list - OCS DMA linked list entry.
+ * @src_addr: Source address of the data.
+ * @src_len: Length of data to be fetched.
+ * @next: Next dma_list to fetch.
+ * @ll_flags: Flags (Freeze @ terminate) for the DMA engine.
+ */
+struct ocs_dma_linked_list {
+ u32 src_addr;
+ u32 src_len;
+ u32 next;
+ u32 ll_flags;
+} __packed;
+
+/*
+ * Set endianness of inputs and outputs
+ * AES_BYTE_ORDER_CFG
+ * default 0x00000000
+ * bit [10] - KEY_HI_LO_SWAP
+ * bit [9] - KEY_HI_SWAP_DWORDS_IN_OCTWORD
+ * bit [8] - KEY_HI_SWAP_BYTES_IN_DWORD
+ * bit [7] - KEY_LO_SWAP_DWORDS_IN_OCTWORD
+ * bit [6] - KEY_LO_SWAP_BYTES_IN_DWORD
+ * bit [5] - IV_SWAP_DWORDS_IN_OCTWORD
+ * bit [4] - IV_SWAP_BYTES_IN_DWORD
+ * bit [3] - DOUT_SWAP_DWORDS_IN_OCTWORD
+ * bit [2] - DOUT_SWAP_BYTES_IN_DWORD
+ * bit [1] - DOUT_SWAP_DWORDS_IN_OCTWORD
+ * bit [0] - DOUT_SWAP_BYTES_IN_DWORD
+ */
+static inline void aes_a_set_endianness(const struct ocs_aes_dev *aes_dev)
+{
+ iowrite32(0x7FF, aes_dev->base_reg + AES_BYTE_ORDER_CFG_OFFSET);
+}
+
+/* Trigger AES process start. */
+static inline void aes_a_op_trigger(const struct ocs_aes_dev *aes_dev)
+{
+ iowrite32(AES_ACTIVE_TRIGGER, aes_dev->base_reg + AES_ACTIVE_OFFSET);
+}
+
+/* Indicate last bulk of data. */
+static inline void aes_a_op_termination(const struct ocs_aes_dev *aes_dev)
+{
+ iowrite32(AES_ACTIVE_TERMINATION,
+ aes_dev->base_reg + AES_ACTIVE_OFFSET);
+}
+
+/*
+ * Set LAST_CCM_GCM in AES_ACTIVE register and clear all other bits.
+ *
+ * Called when DMA is programmed to fetch the last batch of data.
+ * - For AES-CCM it is called for the last batch of Payload data and Ciphertext
+ * data.
+ * - For AES-GCM, it is called for the last batch of Plaintext data and
+ * Ciphertext data.
+ */
+static inline void aes_a_set_last_gcx(const struct ocs_aes_dev *aes_dev)
+{
+ iowrite32(AES_ACTIVE_LAST_CCM_GCM,
+ aes_dev->base_reg + AES_ACTIVE_OFFSET);
+}
+
+/* Wait for LAST_CCM_GCM bit to be unset. */
+static inline void aes_a_wait_last_gcx(const struct ocs_aes_dev *aes_dev)
+{
+ u32 aes_active_reg;
+
+ do {
+ aes_active_reg = ioread32(aes_dev->base_reg +
+ AES_ACTIVE_OFFSET);
+ } while (aes_active_reg & AES_ACTIVE_LAST_CCM_GCM);
+}
+
+/* Wait for 10 bits of input occupancy. */
+static void aes_a_dma_wait_input_buffer_occupancy(const struct ocs_aes_dev *aes_dev)
+{
+ u32 reg;
+
+ do {
+ reg = ioread32(aes_dev->base_reg + AES_A_DMA_STATUS_OFFSET);
+ } while (reg & AES_DMA_STATUS_INPUT_BUFFER_OCCUPANCY_MASK);
+}
+
+ /*
+ * Set LAST_CCM_GCM and LAST_ADATA bits in AES_ACTIVE register (and clear all
+ * other bits).
+ *
+ * Called when DMA is programmed to fetch the last batch of Associated Data
+ * (CCM case) or Additional Authenticated Data (GCM case).
+ */
+static inline void aes_a_set_last_gcx_and_adata(const struct ocs_aes_dev *aes_dev)
+{
+ iowrite32(AES_ACTIVE_LAST_ADATA | AES_ACTIVE_LAST_CCM_GCM,
+ aes_dev->base_reg + AES_ACTIVE_OFFSET);
+}
+
+/* Set DMA src and dst transfer size to 0 */
+static inline void aes_a_dma_set_xfer_size_zero(const struct ocs_aes_dev *aes_dev)
+{
+ iowrite32(0, aes_dev->base_reg + AES_A_DMA_SRC_SIZE_OFFSET);
+ iowrite32(0, aes_dev->base_reg + AES_A_DMA_DST_SIZE_OFFSET);
+}
+
+/* Activate DMA for zero-byte transfer case. */
+static inline void aes_a_dma_active(const struct ocs_aes_dev *aes_dev)
+{
+ iowrite32(AES_A_DMA_DMA_MODE_ACTIVE,
+ aes_dev->base_reg + AES_A_DMA_DMA_MODE_OFFSET);
+}
+
+/* Activate DMA and enable src linked list */
+static inline void aes_a_dma_active_src_ll_en(const struct ocs_aes_dev *aes_dev)
+{
+ iowrite32(AES_A_DMA_DMA_MODE_ACTIVE |
+ AES_A_DMA_DMA_MODE_SRC_LINK_LIST_EN,
+ aes_dev->base_reg + AES_A_DMA_DMA_MODE_OFFSET);
+}
+
+/* Activate DMA and enable dst linked list */
+static inline void aes_a_dma_active_dst_ll_en(const struct ocs_aes_dev *aes_dev)
+{
+ iowrite32(AES_A_DMA_DMA_MODE_ACTIVE |
+ AES_A_DMA_DMA_MODE_DST_LINK_LIST_EN,
+ aes_dev->base_reg + AES_A_DMA_DMA_MODE_OFFSET);
+}
+
+/* Activate DMA and enable src and dst linked lists */
+static inline void aes_a_dma_active_src_dst_ll_en(const struct ocs_aes_dev *aes_dev)
+{
+ iowrite32(AES_A_DMA_DMA_MODE_ACTIVE |
+ AES_A_DMA_DMA_MODE_SRC_LINK_LIST_EN |
+ AES_A_DMA_DMA_MODE_DST_LINK_LIST_EN,
+ aes_dev->base_reg + AES_A_DMA_DMA_MODE_OFFSET);
+}
+
+/* Reset PERF_CNTR to 0 and activate it */
+static inline void aes_a_dma_reset_and_activate_perf_cntr(const struct ocs_aes_dev *aes_dev)
+{
+ iowrite32(0x00000000, aes_dev->base_reg + AES_A_DMA_PERF_CNTR_OFFSET);
+ iowrite32(AES_ACTIVATE_PERF_CNTR,
+ aes_dev->base_reg + AES_A_DMA_WHILE_ACTIVE_MODE_OFFSET);
+}
+
+/* Wait until PERF_CNTR is > delay, then deactivate it */
+static inline void aes_a_dma_wait_and_deactivate_perf_cntr(const struct ocs_aes_dev *aes_dev,
+ int delay)
+{
+ while (ioread32(aes_dev->base_reg + AES_A_DMA_PERF_CNTR_OFFSET) < delay)
+ ;
+ iowrite32(AES_DEACTIVATE_PERF_CNTR,
+ aes_dev->base_reg + AES_A_DMA_WHILE_ACTIVE_MODE_OFFSET);
+}
+
+/* Disable AES and DMA IRQ. */
+static void aes_irq_disable(struct ocs_aes_dev *aes_dev)
+{
+ u32 isr_val = 0;
+
+ /* Disable interrupts */
+ iowrite32(AES_DISABLE_INT,
+ aes_dev->base_reg + AES_A_DMA_MSI_IER_OFFSET);
+ iowrite32(AES_DISABLE_INT, aes_dev->base_reg + AES_IER_OFFSET);
+
+ /* Clear any pending interrupt */
+ isr_val = ioread32(aes_dev->base_reg + AES_A_DMA_MSI_ISR_OFFSET);
+ if (isr_val)
+ iowrite32(isr_val,
+ aes_dev->base_reg + AES_A_DMA_MSI_ISR_OFFSET);
+
+ isr_val = ioread32(aes_dev->base_reg + AES_A_DMA_MSI_MASK_OFFSET);
+ if (isr_val)
+ iowrite32(isr_val,
+ aes_dev->base_reg + AES_A_DMA_MSI_MASK_OFFSET);
+
+ isr_val = ioread32(aes_dev->base_reg + AES_ISR_OFFSET);
+ if (isr_val)
+ iowrite32(isr_val, aes_dev->base_reg + AES_ISR_OFFSET);
+}
+
+/* Enable AES or DMA IRQ. IRQ is disabled once fired. */
+static void aes_irq_enable(struct ocs_aes_dev *aes_dev, u8 irq)
+{
+ if (irq == AES_COMPLETE_INT) {
+ /* Ensure DMA error interrupts are enabled */
+ iowrite32(AES_DMA_CPD_ERR_INT |
+ AES_DMA_OUTBUF_RD_ERR_INT |
+ AES_DMA_OUTBUF_WR_ERR_INT |
+ AES_DMA_INBUF_RD_ERR_INT |
+ AES_DMA_INBUF_WR_ERR_INT |
+ AES_DMA_BAD_COMP_INT |
+ AES_DMA_SAI_INT,
+ aes_dev->base_reg + AES_A_DMA_MSI_IER_OFFSET);
+ /*
+ * AES_IER
+ * default 0x00000000
+ * bits [31:3] - reserved
+ * bit [2] - EN_SKS_ERR
+ * bit [1] - EN_AES_COMPLETE
+ * bit [0] - reserved
+ */
+ iowrite32(AES_COMPLETE_INT, aes_dev->base_reg + AES_IER_OFFSET);
+ return;
+ }
+ if (irq == AES_DMA_SRC_DONE_INT) {
+ /* Ensure AES interrupts are disabled */
+ iowrite32(AES_DISABLE_INT, aes_dev->base_reg + AES_IER_OFFSET);
+ /*
+ * DMA_MSI_IER
+ * default 0x00000000
+ * bits [31:9] - reserved
+ * bit [8] - CPD_ERR_INT_EN
+ * bit [7] - OUTBUF_RD_ERR_INT_EN
+ * bit [6] - OUTBUF_WR_ERR_INT_EN
+ * bit [5] - INBUF_RD_ERR_INT_EN
+ * bit [4] - INBUF_WR_ERR_INT_EN
+ * bit [3] - BAD_COMP_INT_EN
+ * bit [2] - SAI_INT_EN
+ * bit [1] - DST_DONE_INT_EN
+ * bit [0] - SRC_DONE_INT_EN
+ */
+ iowrite32(AES_DMA_CPD_ERR_INT |
+ AES_DMA_OUTBUF_RD_ERR_INT |
+ AES_DMA_OUTBUF_WR_ERR_INT |
+ AES_DMA_INBUF_RD_ERR_INT |
+ AES_DMA_INBUF_WR_ERR_INT |
+ AES_DMA_BAD_COMP_INT |
+ AES_DMA_SAI_INT |
+ AES_DMA_SRC_DONE_INT,
+ aes_dev->base_reg + AES_A_DMA_MSI_IER_OFFSET);
+ }
+}
+
+/* Enable and wait for IRQ (either from OCS AES engine or DMA) */
+static int ocs_aes_irq_enable_and_wait(struct ocs_aes_dev *aes_dev, u8 irq)
+{
+ int rc;
+
+ reinit_completion(&aes_dev->irq_completion);
+ aes_irq_enable(aes_dev, irq);
+ rc = wait_for_completion_interruptible(&aes_dev->irq_completion);
+ if (rc)
+ return rc;
+
+ return aes_dev->dma_err_mask ? -EIO : 0;
+}
+
+/* Configure DMA to OCS, linked list mode */
+static inline void dma_to_ocs_aes_ll(struct ocs_aes_dev *aes_dev,
+ dma_addr_t dma_list)
+{
+ iowrite32(0, aes_dev->base_reg + AES_A_DMA_SRC_SIZE_OFFSET);
+ iowrite32(dma_list,
+ aes_dev->base_reg + AES_A_DMA_NEXT_SRC_DESCR_OFFSET);
+}
+
+/* Configure DMA from OCS, linked list mode */
+static inline void dma_from_ocs_aes_ll(struct ocs_aes_dev *aes_dev,
+ dma_addr_t dma_list)
+{
+ iowrite32(0, aes_dev->base_reg + AES_A_DMA_DST_SIZE_OFFSET);
+ iowrite32(dma_list,
+ aes_dev->base_reg + AES_A_DMA_NEXT_DST_DESCR_OFFSET);
+}
+
+irqreturn_t ocs_aes_irq_handler(int irq, void *dev_id)
+{
+ struct ocs_aes_dev *aes_dev = dev_id;
+ u32 aes_dma_isr;
+
+ /* Read DMA ISR status. */
+ aes_dma_isr = ioread32(aes_dev->base_reg + AES_A_DMA_MSI_ISR_OFFSET);
+
+ /* Disable and clear interrupts. */
+ aes_irq_disable(aes_dev);
+
+ /* Save DMA error status. */
+ aes_dev->dma_err_mask = aes_dma_isr &
+ (AES_DMA_CPD_ERR_INT |
+ AES_DMA_OUTBUF_RD_ERR_INT |
+ AES_DMA_OUTBUF_WR_ERR_INT |
+ AES_DMA_INBUF_RD_ERR_INT |
+ AES_DMA_INBUF_WR_ERR_INT |
+ AES_DMA_BAD_COMP_INT |
+ AES_DMA_SAI_INT);
+
+ /* Signal IRQ completion. */
+ complete(&aes_dev->irq_completion);
+
+ return IRQ_HANDLED;
+}
+
+/**
+ * ocs_aes_set_key() - Write key into OCS AES hardware.
+ * @aes_dev: The OCS AES device to write the key to.
+ * @key_size: The size of the key (in bytes).
+ * @key: The key to write.
+ * @cipher: The cipher the key is for.
+ *
+ * For AES @key_size must be either 16 or 32. For SM4 @key_size must be 16.
+ *
+ * Return: 0 on success, negative error code otherwise.
+ */
+int ocs_aes_set_key(struct ocs_aes_dev *aes_dev, u32 key_size, const u8 *key,
+ enum ocs_cipher cipher)
+{
+ const u32 *key_u32;
+ u32 val;
+ int i;
+
+ /* OCS AES supports 128-bit and 256-bit keys only. */
+ if (cipher == OCS_AES && !(key_size == 32 || key_size == 16)) {
+ dev_err(aes_dev->dev,
+ "%d-bit keys not supported by AES cipher\n",
+ key_size * 8);
+ return -EINVAL;
+ }
+ /* OCS SM4 supports 128-bit keys only. */
+ if (cipher == OCS_SM4 && key_size != 16) {
+ dev_err(aes_dev->dev,
+ "%d-bit keys not supported for SM4 cipher\n",
+ key_size * 8);
+ return -EINVAL;
+ }
+
+ if (!key)
+ return -EINVAL;
+
+ key_u32 = (const u32 *)key;
+
+ /* Write key to AES_KEY[0-7] registers */
+ for (i = 0; i < (key_size / sizeof(u32)); i++) {
+ iowrite32(key_u32[i],
+ aes_dev->base_reg + AES_KEY_0_OFFSET +
+ (i * sizeof(u32)));
+ }
+ /*
+ * Write key size
+ * bits [31:1] - reserved
+ * bit [0] - AES_KEY_SIZE
+ * 0 - 128 bit key
+ * 1 - 256 bit key
+ */
+ val = (key_size == 16) ? AES_128_BIT_KEY : AES_256_BIT_KEY;
+ iowrite32(val, aes_dev->base_reg + AES_KEY_SIZE_OFFSET);
+
+ return 0;
+}
+
+/* Write AES_COMMAND */
+static inline void set_ocs_aes_command(struct ocs_aes_dev *aes_dev,
+ enum ocs_cipher cipher,
+ enum ocs_mode mode,
+ enum ocs_instruction instruction)
+{
+ u32 val;
+
+ /* AES_COMMAND
+ * default 0x000000CC
+ * bit [14] - CIPHER_SELECT
+ * 0 - AES
+ * 1 - SM4
+ * bits [11:8] - OCS_AES_MODE
+ * 0000 - ECB
+ * 0001 - CBC
+ * 0010 - CTR
+ * 0110 - CCM
+ * 0111 - GCM
+ * 1001 - CTS
+ * bits [7:6] - AES_INSTRUCTION
+ * 00 - ENCRYPT
+ * 01 - DECRYPT
+ * 10 - EXPAND
+ * 11 - BYPASS
+ * bits [3:2] - CTR_M_BITS
+ * 00 - No increment
+ * 01 - Least significant 32 bits are incremented
+ * 10 - Least significant 64 bits are incremented
+ * 11 - Full 128 bits are incremented
+ */
+ val = (cipher << 14) | (mode << 8) | (instruction << 6) |
+ (AES_CTR_M_128_INC << 2);
+ iowrite32(val, aes_dev->base_reg + AES_COMMAND_OFFSET);
+}
+
+static void ocs_aes_init(struct ocs_aes_dev *aes_dev,
+ enum ocs_mode mode,
+ enum ocs_cipher cipher,
+ enum ocs_instruction instruction)
+{
+ /* Ensure interrupts are disabled and pending interrupts cleared. */
+ aes_irq_disable(aes_dev);
+
+ /* Set endianness recommended by data-sheet. */
+ aes_a_set_endianness(aes_dev);
+
+ /* Set AES_COMMAND register. */
+ set_ocs_aes_command(aes_dev, cipher, mode, instruction);
+}
+
+/*
+ * Write the byte length of the last AES/SM4 block of Payload data (without
+ * zero padding and without the length of the MAC) in register AES_PLEN.
+ */
+static inline void ocs_aes_write_last_data_blk_len(struct ocs_aes_dev *aes_dev,
+ u32 size)
+{
+ u32 val;
+
+ if (size == 0) {
+ val = 0;
+ goto exit;
+ }
+
+ val = size % AES_BLOCK_SIZE;
+ if (val == 0)
+ val = AES_BLOCK_SIZE;
+
+exit:
+ iowrite32(val, aes_dev->base_reg + AES_PLEN_OFFSET);
+}
+
+/*
+ * Validate inputs according to mode.
+ * If OK return 0; else return -EINVAL.
+ */
+static int ocs_aes_validate_inputs(dma_addr_t src_dma_list, u32 src_size,
+ const u8 *iv, u32 iv_size,
+ dma_addr_t aad_dma_list, u32 aad_size,
+ const u8 *tag, u32 tag_size,
+ enum ocs_cipher cipher, enum ocs_mode mode,
+ enum ocs_instruction instruction,
+ dma_addr_t dst_dma_list)
+{
+ /* Ensure cipher, mode and instruction are valid. */
+ if (!(cipher == OCS_AES || cipher == OCS_SM4))
+ return -EINVAL;
+
+ if (mode != OCS_MODE_ECB && mode != OCS_MODE_CBC &&
+ mode != OCS_MODE_CTR && mode != OCS_MODE_CCM &&
+ mode != OCS_MODE_GCM && mode != OCS_MODE_CTS)
+ return -EINVAL;
+
+ if (instruction != OCS_ENCRYPT && instruction != OCS_DECRYPT &&
+ instruction != OCS_EXPAND && instruction != OCS_BYPASS)
+ return -EINVAL;
+
+ /*
+ * When instruction is OCS_BYPASS, OCS simply copies data from source
+ * to destination using DMA.
+ *
+ * AES mode is irrelevant, but both source and destination DMA
+ * linked-list must be defined.
+ */
+ if (instruction == OCS_BYPASS) {
+ if (src_dma_list == DMA_MAPPING_ERROR ||
+ dst_dma_list == DMA_MAPPING_ERROR)
+ return -EINVAL;
+
+ return 0;
+ }
+
+ /*
+ * For performance reasons switch based on mode to limit unnecessary
+ * conditionals for each mode
+ */
+ switch (mode) {
+ case OCS_MODE_ECB:
+ /* Ensure input length is multiple of block size */
+ if (src_size % AES_BLOCK_SIZE != 0)
+ return -EINVAL;
+
+ /* Ensure source and destination linked lists are created */
+ if (src_dma_list == DMA_MAPPING_ERROR ||
+ dst_dma_list == DMA_MAPPING_ERROR)
+ return -EINVAL;
+
+ return 0;
+
+ case OCS_MODE_CBC:
+ /* Ensure input length is multiple of block size */
+ if (src_size % AES_BLOCK_SIZE != 0)
+ return -EINVAL;
+
+ /* Ensure source and destination linked lists are created */
+ if (src_dma_list == DMA_MAPPING_ERROR ||
+ dst_dma_list == DMA_MAPPING_ERROR)
+ return -EINVAL;
+
+ /* Ensure IV is present and block size in length */
+ if (!iv || iv_size != AES_BLOCK_SIZE)
+ return -EINVAL;
+
+ return 0;
+
+ case OCS_MODE_CTR:
+ /* Ensure input length of 1 byte or greater */
+ if (src_size == 0)
+ return -EINVAL;
+
+ /* Ensure source and destination linked lists are created */
+ if (src_dma_list == DMA_MAPPING_ERROR ||
+ dst_dma_list == DMA_MAPPING_ERROR)
+ return -EINVAL;
+
+ /* Ensure IV is present and block size in length */
+ if (!iv || iv_size != AES_BLOCK_SIZE)
+ return -EINVAL;
+
+ return 0;
+
+ case OCS_MODE_CTS:
+ /* Ensure input length >= block size */
+ if (src_size < AES_BLOCK_SIZE)
+ return -EINVAL;
+
+ /* Ensure source and destination linked lists are created */
+ if (src_dma_list == DMA_MAPPING_ERROR ||
+ dst_dma_list == DMA_MAPPING_ERROR)
+ return -EINVAL;
+
+ /* Ensure IV is present and block size in length */
+ if (!iv || iv_size != AES_BLOCK_SIZE)
+ return -EINVAL;
+
+ return 0;
+
+ case OCS_MODE_GCM:
+ /* Ensure IV is present and GCM_AES_IV_SIZE in length */
+ if (!iv || iv_size != GCM_AES_IV_SIZE)
+ return -EINVAL;
+
+ /*
+ * If input data present ensure source and destination linked
+ * lists are created
+ */
+ if (src_size && (src_dma_list == DMA_MAPPING_ERROR ||
+ dst_dma_list == DMA_MAPPING_ERROR))
+ return -EINVAL;
+
+ /* If aad present ensure aad linked list is created */
+ if (aad_size && aad_dma_list == DMA_MAPPING_ERROR)
+ return -EINVAL;
+
+ /* Ensure tag destination is set */
+ if (!tag)
+ return -EINVAL;
+
+ /* Just ensure that tag_size doesn't cause overflows. */
+ if (tag_size > (AES_MAX_TAG_SIZE_U32 * sizeof(u32)))
+ return -EINVAL;
+
+ return 0;
+
+ case OCS_MODE_CCM:
+ /* Ensure IV is present and block size in length */
+ if (!iv || iv_size != AES_BLOCK_SIZE)
+ return -EINVAL;
+
+ /* 2 <= L <= 8, so 1 <= L' <= 7 */
+ if (iv[L_PRIME_IDX] < L_PRIME_MIN ||
+ iv[L_PRIME_IDX] > L_PRIME_MAX)
+ return -EINVAL;
+
+ /* If aad present ensure aad linked list is created */
+ if (aad_size && aad_dma_list == DMA_MAPPING_ERROR)
+ return -EINVAL;
+
+ /* Just ensure that tag_size doesn't cause overflows. */
+ if (tag_size > (AES_MAX_TAG_SIZE_U32 * sizeof(u32)))
+ return -EINVAL;
+
+ if (instruction == OCS_DECRYPT) {
+ /*
+ * If input data present ensure source and destination
+ * linked lists are created
+ */
+ if (src_size && (src_dma_list == DMA_MAPPING_ERROR ||
+ dst_dma_list == DMA_MAPPING_ERROR))
+ return -EINVAL;
+
+ /* Ensure input tag is present */
+ if (!tag)
+ return -EINVAL;
+
+ return 0;
+ }
+
+ /* Instruction == OCS_ENCRYPT */
+
+ /*
+ * Destination linked list always required (for tag even if no
+ * input data)
+ */
+ if (dst_dma_list == DMA_MAPPING_ERROR)
+ return -EINVAL;
+
+ /* If input data present ensure src linked list is created */
+ if (src_size && src_dma_list == DMA_MAPPING_ERROR)
+ return -EINVAL;
+
+ return 0;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+/**
+ * ocs_aes_op() - Perform AES/SM4 operation.
+ * @aes_dev: The OCS AES device to use.
+ * @mode: The mode to use (ECB, CBC, CTR, or CTS).
+ * @cipher: The cipher to use (AES or SM4).
+ * @instruction: The instruction to perform (encrypt or decrypt).
+ * @dst_dma_list: The OCS DMA list mapping output memory.
+ * @src_dma_list: The OCS DMA list mapping input payload data.
+ * @src_size: The amount of data mapped by @src_dma_list.
+ * @iv: The IV vector.
+ * @iv_size: The size (in bytes) of @iv.
+ *
+ * Return: 0 on success, negative error code otherwise.
+ */
+int ocs_aes_op(struct ocs_aes_dev *aes_dev,
+ enum ocs_mode mode,
+ enum ocs_cipher cipher,
+ enum ocs_instruction instruction,
+ dma_addr_t dst_dma_list,
+ dma_addr_t src_dma_list,
+ u32 src_size,
+ u8 *iv,
+ u32 iv_size)
+{
+ u32 *iv32;
+ int rc;
+
+ rc = ocs_aes_validate_inputs(src_dma_list, src_size, iv, iv_size, 0, 0,
+ NULL, 0, cipher, mode, instruction,
+ dst_dma_list);
+ if (rc)
+ return rc;
+ /*
+ * ocs_aes_validate_inputs() is a generic check, now ensure mode is not
+ * GCM or CCM.
+ */
+ if (mode == OCS_MODE_GCM || mode == OCS_MODE_CCM)
+ return -EINVAL;
+
+ /* Cast IV to u32 array. */
+ iv32 = (u32 *)iv;
+
+ ocs_aes_init(aes_dev, mode, cipher, instruction);
+
+ if (mode == OCS_MODE_CTS) {
+ /* Write the byte length of the last data block to engine. */
+ ocs_aes_write_last_data_blk_len(aes_dev, src_size);
+ }
+
+ /* ECB is the only mode that doesn't use IV. */
+ if (mode != OCS_MODE_ECB) {
+ iowrite32(iv32[0], aes_dev->base_reg + AES_IV_0_OFFSET);
+ iowrite32(iv32[1], aes_dev->base_reg + AES_IV_1_OFFSET);
+ iowrite32(iv32[2], aes_dev->base_reg + AES_IV_2_OFFSET);
+ iowrite32(iv32[3], aes_dev->base_reg + AES_IV_3_OFFSET);
+ }
+
+ /* Set AES_ACTIVE.TRIGGER to start the operation. */
+ aes_a_op_trigger(aes_dev);
+
+ /* Configure and activate input / output DMA. */
+ dma_to_ocs_aes_ll(aes_dev, src_dma_list);
+ dma_from_ocs_aes_ll(aes_dev, dst_dma_list);
+ aes_a_dma_active_src_dst_ll_en(aes_dev);
+
+ if (mode == OCS_MODE_CTS) {
+ /*
+ * For CTS mode, instruct engine to activate ciphertext
+ * stealing if last block of data is incomplete.
+ */
+ aes_a_set_last_gcx(aes_dev);
+ } else {
+ /* For all other modes, just write the 'termination' bit. */
+ aes_a_op_termination(aes_dev);
+ }
+
+ /* Wait for engine to complete processing. */
+ rc = ocs_aes_irq_enable_and_wait(aes_dev, AES_COMPLETE_INT);
+ if (rc)
+ return rc;
+
+ if (mode == OCS_MODE_CTR) {
+ /* Read back IV for streaming mode */
+ iv32[0] = ioread32(aes_dev->base_reg + AES_IV_0_OFFSET);
+ iv32[1] = ioread32(aes_dev->base_reg + AES_IV_1_OFFSET);
+ iv32[2] = ioread32(aes_dev->base_reg + AES_IV_2_OFFSET);
+ iv32[3] = ioread32(aes_dev->base_reg + AES_IV_3_OFFSET);
+ }
+
+ return 0;
+}
+
+/* Compute and write J0 to engine registers. */
+static void ocs_aes_gcm_write_j0(const struct ocs_aes_dev *aes_dev,
+ const u8 *iv)
+{
+ const u32 *j0 = (u32 *)iv;
+
+ /*
+ * IV must be 12 bytes; Other sizes not supported as Linux crypto API
+ * does only expects/allows 12 byte IV for GCM
+ */
+ iowrite32(0x00000001, aes_dev->base_reg + AES_IV_0_OFFSET);
+ iowrite32(__swab32(j0[2]), aes_dev->base_reg + AES_IV_1_OFFSET);
+ iowrite32(__swab32(j0[1]), aes_dev->base_reg + AES_IV_2_OFFSET);
+ iowrite32(__swab32(j0[0]), aes_dev->base_reg + AES_IV_3_OFFSET);
+}
+
+/* Read GCM tag from engine registers. */
+static inline void ocs_aes_gcm_read_tag(struct ocs_aes_dev *aes_dev,
+ u8 *tag, u32 tag_size)
+{
+ u32 tag_u32[AES_MAX_TAG_SIZE_U32];
+
+ /*
+ * The Authentication Tag T is stored in Little Endian order in the
+ * registers with the most significant bytes stored from AES_T_MAC[3]
+ * downward.
+ */
+ tag_u32[0] = __swab32(ioread32(aes_dev->base_reg + AES_T_MAC_3_OFFSET));
+ tag_u32[1] = __swab32(ioread32(aes_dev->base_reg + AES_T_MAC_2_OFFSET));
+ tag_u32[2] = __swab32(ioread32(aes_dev->base_reg + AES_T_MAC_1_OFFSET));
+ tag_u32[3] = __swab32(ioread32(aes_dev->base_reg + AES_T_MAC_0_OFFSET));
+
+ memcpy(tag, tag_u32, tag_size);
+}
+
+/**
+ * ocs_aes_gcm_op() - Perform GCM operation.
+ * @aes_dev: The OCS AES device to use.
+ * @cipher: The Cipher to use (AES or SM4).
+ * @instruction: The instruction to perform (encrypt or decrypt).
+ * @dst_dma_list: The OCS DMA list mapping output memory.
+ * @src_dma_list: The OCS DMA list mapping input payload data.
+ * @src_size: The amount of data mapped by @src_dma_list.
+ * @iv: The input IV vector.
+ * @aad_dma_list: The OCS DMA list mapping input AAD data.
+ * @aad_size: The amount of data mapped by @aad_dma_list.
+ * @out_tag: Where to store computed tag.
+ * @tag_size: The size (in bytes) of @out_tag.
+ *
+ * Return: 0 on success, negative error code otherwise.
+ */
+int ocs_aes_gcm_op(struct ocs_aes_dev *aes_dev,
+ enum ocs_cipher cipher,
+ enum ocs_instruction instruction,
+ dma_addr_t dst_dma_list,
+ dma_addr_t src_dma_list,
+ u32 src_size,
+ const u8 *iv,
+ dma_addr_t aad_dma_list,
+ u32 aad_size,
+ u8 *out_tag,
+ u32 tag_size)
+{
+ u64 bit_len;
+ u32 val;
+ int rc;
+
+ rc = ocs_aes_validate_inputs(src_dma_list, src_size, iv,
+ GCM_AES_IV_SIZE, aad_dma_list,
+ aad_size, out_tag, tag_size, cipher,
+ OCS_MODE_GCM, instruction,
+ dst_dma_list);
+ if (rc)
+ return rc;
+
+ ocs_aes_init(aes_dev, OCS_MODE_GCM, cipher, instruction);
+
+ /* Compute and write J0 to OCS HW. */
+ ocs_aes_gcm_write_j0(aes_dev, iv);
+
+ /* Write out_tag byte length */
+ iowrite32(tag_size, aes_dev->base_reg + AES_TLEN_OFFSET);
+
+ /* Write the byte length of the last plaintext / ciphertext block. */
+ ocs_aes_write_last_data_blk_len(aes_dev, src_size);
+
+ /* Write ciphertext bit length */
+ bit_len = (u64)src_size * 8;
+ val = bit_len & 0xFFFFFFFF;
+ iowrite32(val, aes_dev->base_reg + AES_MULTIPURPOSE2_0_OFFSET);
+ val = bit_len >> 32;
+ iowrite32(val, aes_dev->base_reg + AES_MULTIPURPOSE2_1_OFFSET);
+
+ /* Write aad bit length */
+ bit_len = (u64)aad_size * 8;
+ val = bit_len & 0xFFFFFFFF;
+ iowrite32(val, aes_dev->base_reg + AES_MULTIPURPOSE2_2_OFFSET);
+ val = bit_len >> 32;
+ iowrite32(val, aes_dev->base_reg + AES_MULTIPURPOSE2_3_OFFSET);
+
+ /* Set AES_ACTIVE.TRIGGER to start the operation. */
+ aes_a_op_trigger(aes_dev);
+
+ /* Process AAD. */
+ if (aad_size) {
+ /* If aad present, configure DMA to feed it to the engine. */
+ dma_to_ocs_aes_ll(aes_dev, aad_dma_list);
+ aes_a_dma_active_src_ll_en(aes_dev);
+
+ /* Instructs engine to pad last block of aad, if needed. */
+ aes_a_set_last_gcx_and_adata(aes_dev);
+
+ /* Wait for DMA transfer to complete. */
+ rc = ocs_aes_irq_enable_and_wait(aes_dev, AES_DMA_SRC_DONE_INT);
+ if (rc)
+ return rc;
+ } else {
+ aes_a_set_last_gcx_and_adata(aes_dev);
+ }
+
+ /* Wait until adata (if present) has been processed. */
+ aes_a_wait_last_gcx(aes_dev);
+ aes_a_dma_wait_input_buffer_occupancy(aes_dev);
+
+ /* Now process payload. */
+ if (src_size) {
+ /* Configure and activate DMA for both input and output data. */
+ dma_to_ocs_aes_ll(aes_dev, src_dma_list);
+ dma_from_ocs_aes_ll(aes_dev, dst_dma_list);
+ aes_a_dma_active_src_dst_ll_en(aes_dev);
+ } else {
+ aes_a_dma_set_xfer_size_zero(aes_dev);
+ aes_a_dma_active(aes_dev);
+ }
+
+ /* Instruct AES/SMA4 engine payload processing is over. */
+ aes_a_set_last_gcx(aes_dev);
+
+ /* Wait for OCS AES engine to complete processing. */
+ rc = ocs_aes_irq_enable_and_wait(aes_dev, AES_COMPLETE_INT);
+ if (rc)
+ return rc;
+
+ ocs_aes_gcm_read_tag(aes_dev, out_tag, tag_size);
+
+ return 0;
+}
+
+/* Write encrypted tag to AES/SM4 engine. */
+static void ocs_aes_ccm_write_encrypted_tag(struct ocs_aes_dev *aes_dev,
+ const u8 *in_tag, u32 tag_size)
+{
+ int i;
+
+ /* Ensure DMA input buffer is empty */
+ aes_a_dma_wait_input_buffer_occupancy(aes_dev);
+
+ /*
+ * During CCM decrypt, the OCS block needs to finish processing the
+ * ciphertext before the tag is written. So delay needed after DMA has
+ * completed writing the ciphertext
+ */
+ aes_a_dma_reset_and_activate_perf_cntr(aes_dev);
+ aes_a_dma_wait_and_deactivate_perf_cntr(aes_dev,
+ CCM_DECRYPT_DELAY_TAG_CLK_COUNT);
+
+ /* Write encrypted tag to AES/SM4 engine. */
+ for (i = 0; i < tag_size; i++) {
+ iowrite8(in_tag[i], aes_dev->base_reg +
+ AES_A_DMA_INBUFFER_WRITE_FIFO_OFFSET);
+ }
+}
+
+/*
+ * Write B0 CCM block to OCS AES HW.
+ *
+ * Note: B0 format is documented in NIST Special Publication 800-38C
+ * https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-38c.pdf
+ * (see Section A.2.1)
+ */
+static int ocs_aes_ccm_write_b0(const struct ocs_aes_dev *aes_dev,
+ const u8 *iv, u32 adata_size, u32 tag_size,
+ u32 cryptlen)
+{
+ u8 b0[16]; /* CCM B0 block is 16 bytes long. */
+ int i, q;
+
+ /* Initialize B0 to 0. */
+ memset(b0, 0, sizeof(b0));
+
+ /*
+ * B0[0] is the 'Flags Octet' and has the following structure:
+ * bit 7: Reserved
+ * bit 6: Adata flag
+ * bit 5-3: t value encoded as (t-2)/2
+ * bit 2-0: q value encoded as q - 1
+ */
+ /* If there is AAD data, set the Adata flag. */
+ if (adata_size)
+ b0[0] |= BIT(6);
+ /*
+ * t denotes the octet length of T.
+ * t can only be an element of { 4, 6, 8, 10, 12, 14, 16} and is
+ * encoded as (t - 2) / 2
+ */
+ b0[0] |= (((tag_size - 2) / 2) & 0x7) << 3;
+ /*
+ * q is the octet length of Q.
+ * q can only be an element of {2, 3, 4, 5, 6, 7, 8} and is encoded as
+ * q - 1 == iv[0] & 0x7;
+ */
+ b0[0] |= iv[0] & 0x7;
+ /*
+ * Copy the Nonce N from IV to B0; N is located in iv[1]..iv[15 - q]
+ * and must be copied to b0[1]..b0[15-q].
+ * q == (iv[0] & 0x7) + 1
+ */
+ q = (iv[0] & 0x7) + 1;
+ for (i = 1; i <= 15 - q; i++)
+ b0[i] = iv[i];
+ /*
+ * The rest of B0 must contain Q, i.e., the message length.
+ * Q is encoded in q octets, in big-endian order, so to write it, we
+ * start from the end of B0 and we move backward.
+ */
+ i = sizeof(b0) - 1;
+ while (q) {
+ b0[i] = cryptlen & 0xff;
+ cryptlen >>= 8;
+ i--;
+ q--;
+ }
+ /*
+ * If cryptlen is not zero at this point, it means that its original
+ * value was too big.
+ */
+ if (cryptlen)
+ return -EOVERFLOW;
+ /* Now write B0 to OCS AES input buffer. */
+ for (i = 0; i < sizeof(b0); i++)
+ iowrite8(b0[i], aes_dev->base_reg +
+ AES_A_DMA_INBUFFER_WRITE_FIFO_OFFSET);
+ return 0;
+}
+
+/*
+ * Write adata length to OCS AES HW.
+ *
+ * Note: adata len encoding is documented in NIST Special Publication 800-38C
+ * https://nvlpubs.nist.gov/nistpubs/Legacy/SP/nistspecialpublication800-38c.pdf
+ * (see Section A.2.2)
+ */
+static void ocs_aes_ccm_write_adata_len(const struct ocs_aes_dev *aes_dev,
+ u64 adata_len)
+{
+ u8 enc_a[10]; /* Maximum encoded size: 10 octets. */
+ int i, len;
+
+ /*
+ * adata_len ('a') is encoded as follows:
+ * If 0 < a < 2^16 - 2^8 ==> 'a' encoded as [a]16, i.e., two octets
+ * (big endian).
+ * If 2^16 - 2^8 ≤ a < 2^32 ==> 'a' encoded as 0xff || 0xfe || [a]32,
+ * i.e., six octets (big endian).
+ * If 2^32 ≤ a < 2^64 ==> 'a' encoded as 0xff || 0xff || [a]64,
+ * i.e., ten octets (big endian).
+ */
+ if (adata_len < 65280) {
+ len = 2;
+ *(__be16 *)enc_a = cpu_to_be16(adata_len);
+ } else if (adata_len <= 0xFFFFFFFF) {
+ len = 6;
+ *(__be16 *)enc_a = cpu_to_be16(0xfffe);
+ *(__be32 *)&enc_a[2] = cpu_to_be32(adata_len);
+ } else { /* adata_len >= 2^32 */
+ len = 10;
+ *(__be16 *)enc_a = cpu_to_be16(0xffff);
+ *(__be64 *)&enc_a[2] = cpu_to_be64(adata_len);
+ }
+ for (i = 0; i < len; i++)
+ iowrite8(enc_a[i],
+ aes_dev->base_reg +
+ AES_A_DMA_INBUFFER_WRITE_FIFO_OFFSET);
+}
+
+static int ocs_aes_ccm_do_adata(struct ocs_aes_dev *aes_dev,
+ dma_addr_t adata_dma_list, u32 adata_size)
+{
+ int rc;
+
+ if (!adata_size) {
+ /* Since no aad the LAST_GCX bit can be set now */
+ aes_a_set_last_gcx_and_adata(aes_dev);
+ goto exit;
+ }
+
+ /* Adata case. */
+
+ /*
+ * Form the encoding of the Associated data length and write it
+ * to the AES/SM4 input buffer.
+ */
+ ocs_aes_ccm_write_adata_len(aes_dev, adata_size);
+
+ /* Configure the AES/SM4 DMA to fetch the Associated Data */
+ dma_to_ocs_aes_ll(aes_dev, adata_dma_list);
+
+ /* Activate DMA to fetch Associated data. */
+ aes_a_dma_active_src_ll_en(aes_dev);
+
+ /* Set LAST_GCX and LAST_ADATA in AES ACTIVE register. */
+ aes_a_set_last_gcx_and_adata(aes_dev);
+
+ /* Wait for DMA transfer to complete. */
+ rc = ocs_aes_irq_enable_and_wait(aes_dev, AES_DMA_SRC_DONE_INT);
+ if (rc)
+ return rc;
+
+exit:
+ /* Wait until adata (if present) has been processed. */
+ aes_a_wait_last_gcx(aes_dev);
+ aes_a_dma_wait_input_buffer_occupancy(aes_dev);
+
+ return 0;
+}
+
+static int ocs_aes_ccm_encrypt_do_payload(struct ocs_aes_dev *aes_dev,
+ dma_addr_t dst_dma_list,
+ dma_addr_t src_dma_list,
+ u32 src_size)
+{
+ if (src_size) {
+ /*
+ * Configure and activate DMA for both input and output
+ * data.
+ */
+ dma_to_ocs_aes_ll(aes_dev, src_dma_list);
+ dma_from_ocs_aes_ll(aes_dev, dst_dma_list);
+ aes_a_dma_active_src_dst_ll_en(aes_dev);
+ } else {
+ /* Configure and activate DMA for output data only. */
+ dma_from_ocs_aes_ll(aes_dev, dst_dma_list);
+ aes_a_dma_active_dst_ll_en(aes_dev);
+ }
+
+ /*
+ * Set the LAST GCX bit in AES_ACTIVE Register to instruct
+ * AES/SM4 engine to pad the last block of data.
+ */
+ aes_a_set_last_gcx(aes_dev);
+
+ /* We are done, wait for IRQ and return. */
+ return ocs_aes_irq_enable_and_wait(aes_dev, AES_COMPLETE_INT);
+}
+
+static int ocs_aes_ccm_decrypt_do_payload(struct ocs_aes_dev *aes_dev,
+ dma_addr_t dst_dma_list,
+ dma_addr_t src_dma_list,
+ u32 src_size)
+{
+ if (!src_size) {
+ /* Let engine process 0-length input. */
+ aes_a_dma_set_xfer_size_zero(aes_dev);
+ aes_a_dma_active(aes_dev);
+ aes_a_set_last_gcx(aes_dev);
+
+ return 0;
+ }
+
+ /*
+ * Configure and activate DMA for both input and output
+ * data.
+ */
+ dma_to_ocs_aes_ll(aes_dev, src_dma_list);
+ dma_from_ocs_aes_ll(aes_dev, dst_dma_list);
+ aes_a_dma_active_src_dst_ll_en(aes_dev);
+ /*
+ * Set the LAST GCX bit in AES_ACTIVE Register; this allows the
+ * AES/SM4 engine to differentiate between encrypted data and
+ * encrypted MAC.
+ */
+ aes_a_set_last_gcx(aes_dev);
+ /*
+ * Enable DMA DONE interrupt; once DMA transfer is over,
+ * interrupt handler will process the MAC/tag.
+ */
+ return ocs_aes_irq_enable_and_wait(aes_dev, AES_DMA_SRC_DONE_INT);
+}
+
+/*
+ * Compare Tag to Yr.
+ *
+ * Only used at the end of CCM decrypt. If tag == yr, message authentication
+ * has succeeded.
+ */
+static inline int ccm_compare_tag_to_yr(struct ocs_aes_dev *aes_dev,
+ u8 tag_size_bytes)
+{
+ u32 tag[AES_MAX_TAG_SIZE_U32];
+ u32 yr[AES_MAX_TAG_SIZE_U32];
+ u8 i;
+
+ /* Read Tag and Yr from AES registers. */
+ for (i = 0; i < AES_MAX_TAG_SIZE_U32; i++) {
+ tag[i] = ioread32(aes_dev->base_reg +
+ AES_T_MAC_0_OFFSET + (i * sizeof(u32)));
+ yr[i] = ioread32(aes_dev->base_reg +
+ AES_MULTIPURPOSE2_0_OFFSET +
+ (i * sizeof(u32)));
+ }
+
+ return memcmp(tag, yr, tag_size_bytes) ? -EBADMSG : 0;
+}
+
+/**
+ * ocs_aes_ccm_op() - Perform CCM operation.
+ * @aes_dev: The OCS AES device to use.
+ * @cipher: The Cipher to use (AES or SM4).
+ * @instruction: The instruction to perform (encrypt or decrypt).
+ * @dst_dma_list: The OCS DMA list mapping output memory.
+ * @src_dma_list: The OCS DMA list mapping input payload data.
+ * @src_size: The amount of data mapped by @src_dma_list.
+ * @iv: The input IV vector.
+ * @adata_dma_list: The OCS DMA list mapping input A-data.
+ * @adata_size: The amount of data mapped by @adata_dma_list.
+ * @in_tag: Input tag.
+ * @tag_size: The size (in bytes) of @in_tag.
+ *
+ * Note: for encrypt the tag is appended to the ciphertext (in the memory
+ * mapped by @dst_dma_list).
+ *
+ * Return: 0 on success, negative error code otherwise.
+ */
+int ocs_aes_ccm_op(struct ocs_aes_dev *aes_dev,
+ enum ocs_cipher cipher,
+ enum ocs_instruction instruction,
+ dma_addr_t dst_dma_list,
+ dma_addr_t src_dma_list,
+ u32 src_size,
+ u8 *iv,
+ dma_addr_t adata_dma_list,
+ u32 adata_size,
+ u8 *in_tag,
+ u32 tag_size)
+{
+ u32 *iv_32;
+ u8 lprime;
+ int rc;
+
+ rc = ocs_aes_validate_inputs(src_dma_list, src_size, iv,
+ AES_BLOCK_SIZE, adata_dma_list, adata_size,
+ in_tag, tag_size, cipher, OCS_MODE_CCM,
+ instruction, dst_dma_list);
+ if (rc)
+ return rc;
+
+ ocs_aes_init(aes_dev, OCS_MODE_CCM, cipher, instruction);
+
+ /*
+ * Note: rfc 3610 and NIST 800-38C require counter of zero to encrypt
+ * auth tag so ensure this is the case
+ */
+ lprime = iv[L_PRIME_IDX];
+ memset(&iv[COUNTER_START(lprime)], 0, COUNTER_LEN(lprime));
+
+ /*
+ * Nonce is already converted to ctr0 before being passed into this
+ * function as iv.
+ */
+ iv_32 = (u32 *)iv;
+ iowrite32(__swab32(iv_32[0]),
+ aes_dev->base_reg + AES_MULTIPURPOSE1_3_OFFSET);
+ iowrite32(__swab32(iv_32[1]),
+ aes_dev->base_reg + AES_MULTIPURPOSE1_2_OFFSET);
+ iowrite32(__swab32(iv_32[2]),
+ aes_dev->base_reg + AES_MULTIPURPOSE1_1_OFFSET);
+ iowrite32(__swab32(iv_32[3]),
+ aes_dev->base_reg + AES_MULTIPURPOSE1_0_OFFSET);
+
+ /* Write MAC/tag length in register AES_TLEN */
+ iowrite32(tag_size, aes_dev->base_reg + AES_TLEN_OFFSET);
+ /*
+ * Write the byte length of the last AES/SM4 block of Payload data
+ * (without zero padding and without the length of the MAC) in register
+ * AES_PLEN.
+ */
+ ocs_aes_write_last_data_blk_len(aes_dev, src_size);
+
+ /* Set AES_ACTIVE.TRIGGER to start the operation. */
+ aes_a_op_trigger(aes_dev);
+
+ aes_a_dma_reset_and_activate_perf_cntr(aes_dev);
+
+ /* Form block B0 and write it to the AES/SM4 input buffer. */
+ rc = ocs_aes_ccm_write_b0(aes_dev, iv, adata_size, tag_size, src_size);
+ if (rc)
+ return rc;
+ /*
+ * Ensure there has been at least CCM_DECRYPT_DELAY_LAST_GCX_CLK_COUNT
+ * clock cycles since TRIGGER bit was set
+ */
+ aes_a_dma_wait_and_deactivate_perf_cntr(aes_dev,
+ CCM_DECRYPT_DELAY_LAST_GCX_CLK_COUNT);
+
+ /* Process Adata. */
+ ocs_aes_ccm_do_adata(aes_dev, adata_dma_list, adata_size);
+
+ /* For Encrypt case we just process the payload and return. */
+ if (instruction == OCS_ENCRYPT) {
+ return ocs_aes_ccm_encrypt_do_payload(aes_dev, dst_dma_list,
+ src_dma_list, src_size);
+ }
+ /* For Decypt we need to process the payload and then the tag. */
+ rc = ocs_aes_ccm_decrypt_do_payload(aes_dev, dst_dma_list,
+ src_dma_list, src_size);
+ if (rc)
+ return rc;
+
+ /* Process MAC/tag directly: feed tag to engine and wait for IRQ. */
+ ocs_aes_ccm_write_encrypted_tag(aes_dev, in_tag, tag_size);
+ rc = ocs_aes_irq_enable_and_wait(aes_dev, AES_COMPLETE_INT);
+ if (rc)
+ return rc;
+
+ return ccm_compare_tag_to_yr(aes_dev, tag_size);
+}
+
+/**
+ * ocs_create_linked_list_from_sg() - Create OCS DMA linked list from SG list.
+ * @aes_dev: The OCS AES device the list will be created for.
+ * @sg: The SG list OCS DMA linked list will be created from. When
+ * passed to this function, @sg must have been already mapped
+ * with dma_map_sg().
+ * @sg_dma_count: The number of DMA-mapped entries in @sg. This must be the
+ * value returned by dma_map_sg() when @sg was mapped.
+ * @dll_desc: The OCS DMA dma_list to use to store information about the
+ * created linked list.
+ * @data_size: The size of the data (from the SG list) to be mapped into the
+ * OCS DMA linked list.
+ * @data_offset: The offset (within the SG list) of the data to be mapped.
+ *
+ * Return: 0 on success, negative error code otherwise.
+ */
+int ocs_create_linked_list_from_sg(const struct ocs_aes_dev *aes_dev,
+ struct scatterlist *sg,
+ int sg_dma_count,
+ struct ocs_dll_desc *dll_desc,
+ size_t data_size, size_t data_offset)
+{
+ struct ocs_dma_linked_list *ll = NULL;
+ struct scatterlist *sg_tmp;
+ unsigned int tmp;
+ int dma_nents;
+ int i;
+
+ if (!dll_desc || !sg || !aes_dev)
+ return -EINVAL;
+
+ /* Default values for when no ddl_desc is created. */
+ dll_desc->vaddr = NULL;
+ dll_desc->dma_addr = DMA_MAPPING_ERROR;
+ dll_desc->size = 0;
+
+ if (data_size == 0)
+ return 0;
+
+ /* Loop over sg_list until we reach entry at specified offset. */
+ while (data_offset >= sg_dma_len(sg)) {
+ data_offset -= sg_dma_len(sg);
+ sg_dma_count--;
+ sg = sg_next(sg);
+ /* If we reach the end of the list, offset was invalid. */
+ if (!sg || sg_dma_count == 0)
+ return -EINVAL;
+ }
+
+ /* Compute number of DMA-mapped SG entries to add into OCS DMA list. */
+ dma_nents = 0;
+ tmp = 0;
+ sg_tmp = sg;
+ while (tmp < data_offset + data_size) {
+ /* If we reach the end of the list, data_size was invalid. */
+ if (!sg_tmp)
+ return -EINVAL;
+ tmp += sg_dma_len(sg_tmp);
+ dma_nents++;
+ sg_tmp = sg_next(sg_tmp);
+ }
+ if (dma_nents > sg_dma_count)
+ return -EINVAL;
+
+ /* Allocate the DMA list, one entry for each SG entry. */
+ dll_desc->size = sizeof(struct ocs_dma_linked_list) * dma_nents;
+ dll_desc->vaddr = dma_alloc_coherent(aes_dev->dev, dll_desc->size,
+ &dll_desc->dma_addr, GFP_KERNEL);
+ if (!dll_desc->vaddr)
+ return -ENOMEM;
+
+ /* Populate DMA linked list entries. */
+ ll = dll_desc->vaddr;
+ for (i = 0; i < dma_nents; i++, sg = sg_next(sg)) {
+ ll[i].src_addr = sg_dma_address(sg) + data_offset;
+ ll[i].src_len = (sg_dma_len(sg) - data_offset) < data_size ?
+ (sg_dma_len(sg) - data_offset) : data_size;
+ data_offset = 0;
+ data_size -= ll[i].src_len;
+ /* Current element points to the DMA address of the next one. */
+ ll[i].next = dll_desc->dma_addr + (sizeof(*ll) * (i + 1));
+ ll[i].ll_flags = 0;
+ }
+ /* Terminate last element. */
+ ll[i - 1].next = 0;
+ ll[i - 1].ll_flags = OCS_LL_DMA_FLAG_TERMINATE;
+
+ return 0;
+}