This change locks down the GP5 eFuses against modification on i.MX8MP SoCs. To cite the i.MX8MP reference manual (Rev. 3): The GP5_LOCK eFuse locks the upper 64 bits of the 128-bit UNIQUE_ID (UID) eFuse field. The users must program the GP5_LOCK eFuse to b'11 (WP+OP), thereby locking the upper 64-bit UID eFuse field. For devices shipped with date codes 2435 and later, the GP5_LOCK has been programmed to b'11 by NXP in production. Only devices with date codes prior to 2435 should be programmed to update the GP5_LOCK eFuse to b'11. Signed-off-by: Stefan Kerkmann <s.kerkmann@xxxxxxxxxxxxxx> --- drivers/hab/hab.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/hab/hab.c b/drivers/hab/hab.c index 0f0c8766f069697944570290cb5796430ddae125..7fb759c152379dda2d43f139baf1aa6cf2051234 100644 --- a/drivers/hab/hab.c +++ b/drivers/hab/hab.c @@ -200,11 +200,15 @@ static int imx8m_hab_lockdown_device_ocotp(unsigned flags) if (ret < 0) return ret; - /* Only i.MX8MQ requires fusing of DIR_BT_DIS */ - if (!cpu_is_mx8mq()) - return ret; + /* Lock upper 64bit of the 128bit UNIQUE_ID eFuse field on i.MX8MP */ + if (cpu_is_mx8mp()) + return imx_ocotp_write_field(MX8MP_OCOTP_GP5_LOCK, 0b11); - return imx_ocotp_write_field(MX8MQ_OCOTP_DIR_BT_DIS, 1); + /* Only i.MX8MQ requires fusing of DIR_BT_DIS */ + if (cpu_is_mx8mq()) + return imx_ocotp_write_field(MX8MQ_OCOTP_DIR_BT_DIS, 1); + + return 0; } static int imx6_hab_device_locked_down_ocotp(void) -- 2.39.5
