mfd: Add support for Loongson Security Engine chip controller

Loongson Security Engine chip supports RNG, SM2, SM3 and SM4 accelerator
engines. This is the base driver for other specific engine drivers.

Co-developed-by: Yinggang Gu <guyinggang@loongson.cn>
Signed-off-by: Yinggang Gu <guyinggang@loongson.cn>
Signed-off-by: Qunqin Zhao <zhaoqunqin@loongson.cn>
Reviewed-by: Huacai Chen <chenhuacai@loongson.cn>
Link: https://lore.kernel.org/r/20250705072045.1067-2-zhaoqunqin@loongson.cn
Signed-off-by: Lee Jones <lee@kernel.org>

1 files changed, 53 insertions, 0 deletions

diff --git a/include/linux/mfd/loongson-se.h b/include/linux/mfd/loongson-se.h
new file mode 100644
index 000000000000..07afa0c2524d
--- /dev/null
+++ b/include/linux/mfd/loongson-se.h
@@ -0,0 +1,53 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/* Copyright (C) 2025 Loongson Technology Corporation Limited */
+
+#ifndef __MFD_LOONGSON_SE_H__
+#define __MFD_LOONGSON_SE_H__
+
+#define LOONGSON_ENGINE_CMD_TIMEOUT_US	10000
+#define SE_SEND_CMD_REG			0x0
+#define SE_SEND_CMD_REG_LEN		0x8
+/* Controller command ID */
+#define SE_CMD_START			0x0
+#define SE_CMD_SET_DMA			0x3
+#define SE_CMD_SET_ENGINE_CMDBUF	0x4
+
+#define SE_S2LINT_STAT			0x88
+#define SE_S2LINT_EN			0x8c
+#define SE_S2LINT_CL			0x94
+#define SE_L2SINT_STAT			0x98
+#define SE_L2SINT_SET			0xa0
+
+#define SE_INT_ALL			0xffffffff
+#define SE_INT_CONTROLLER		BIT(0)
+
+#define SE_ENGINE_MAX			16
+#define SE_ENGINE_RNG			1
+#define SE_CMD_RNG			0x100
+
+#define SE_ENGINE_TPM			5
+#define SE_CMD_TPM			0x500
+
+#define SE_ENGINE_CMD_SIZE		32
+
+struct loongson_se_engine {
+	struct loongson_se *se;
+	int id;
+
+	/* Command buffer */
+	void *command;
+	void *command_ret;
+
+	void *data_buffer;
+	uint buffer_size;
+	/* Data buffer offset to DMA base */
+	uint buffer_off;
+
+	struct completion completion;
+
+};
+
+struct loongson_se_engine *loongson_se_init_engine(struct device *dev, int id);
+int loongson_se_send_engine_cmd(struct loongson_se_engine *engine);
+
+#endif