[PATCH V2 17/30] imx: imx8ulp: start the ELE RNG at boot

[Peng Fan (OSS)]

From: Peng Fan <peng.fan at nxp.com>

On the imx8ulp A1 SoC, the ELE RNG needs to be manually started.

Signed-off-by: Clement Faure <clement.faure at nxp.com>
Signed-off-by: Peng Fan <peng.fan at nxp.com>
---
 arch/arm/include/asm/mach-imx/ele_api.h |  1 +
 board/freescale/imx8ulp_evk/spl.c       | 10 ++++++++++
 drivers/misc/imx_ele/ele_api.c          | 25 +++++++++++++++++++++++++
 3 files changed, 36 insertions(+)

diff --git a/arch/arm/include/asm/mach-imx/ele_api.h b/arch/arm/include/asm/mach-imx/ele_api.h
index 053a23f030b..cfd4ecebb62 100644
--- a/arch/arm/include/asm/mach-imx/ele_api.h
+++ b/arch/arm/include/asm/mach-imx/ele_api.h
@@ -149,4 +149,5 @@ int ele_get_fw_status(u32 *status, u32 *response);
 int ele_release_m33_trout(void);
 int ele_write_secure_fuse(ulong signed_msg_blk, u32 *response);
 int ele_return_lifecycle_update(ulong signed_msg_blk, u32 *response);
+int ele_start_rng(void);
 #endif
diff --git a/board/freescale/imx8ulp_evk/spl.c b/board/freescale/imx8ulp_evk/spl.c
index b7c6ff092b1..66d0f68cc62 100644
--- a/board/freescale/imx8ulp_evk/spl.c
+++ b/board/freescale/imx8ulp_evk/spl.c
@@ -123,6 +123,16 @@ void spl_board_init(void)
 	ret = ele_release_caam(0x7, &res);
 	if (ret)
 		printf("ele release caam failed %d, 0x%x\n", ret, res);
+
+	/*
+	 * RNG start only available on the A1 soc revision.
+	 * Check some JTAG register for the SoC revision.
+	 */
+	if (!is_soc_rev(CHIP_REV_1_0)) {
+		ret = ele_start_rng();
+		if (ret)
+			printf("Fail to start RNG: %d\n", ret);
+	}
 }
 
 void board_init_f(ulong dummy)
diff --git a/drivers/misc/imx_ele/ele_api.c b/drivers/misc/imx_ele/ele_api.c
index 8a14cf6aa92..0c017734a49 100644
--- a/drivers/misc/imx_ele/ele_api.c
+++ b/drivers/misc/imx_ele/ele_api.c
@@ -503,6 +503,31 @@ int ele_get_events(u32 *events, u32 *events_cnt, u32 *response)
 	return ret;
 }
 
+int ele_start_rng(void)
+{
+	struct udevice *dev = gd->arch.ele_dev;
+	int size = sizeof(struct ele_msg);
+	struct ele_msg msg;
+	int ret;
+
+	if (!dev) {
+		printf("ele dev is not initialized\n");
+		return -ENODEV;
+	}
+
+	msg.version = ELE_VERSION;
+	msg.tag = ELE_CMD_TAG;
+	msg.size = 1;
+	msg.command = ELE_START_RNG;
+
+	ret = misc_call(dev, false, &msg, size, &msg, size);
+	if (ret)
+		printf("Error: %s: ret %d, response 0x%x\n",
+		       __func__, ret, msg.data[0]);
+
+	return ret;
+}
+
 int ele_write_secure_fuse(ulong signed_msg_blk, u32 *response)
 {
 	struct udevice *dev = gd->arch.ele_dev;
-- 
2.40.0