[U-Boot] [PATCH] [RFC] imx: dek_blob: Fix lock-up on dek_blob command

[Henri Roosen]

The function blob_encap_dek accesses a CAAM register
 CONFIG_SYS_FSL_JR0_ADDR + 0x102c, before the CAAM clock has been enabled,
which causes the system to lock-up at the dek_blob command.

This patch enables and disables the CAAM clock, because this is also done in
arch/arm/imx-common/hab.c:authenticate_image(). However in my opinion
controlling the clock should be done in one of the underlaying layers, so
this needs further cleanup.

Please comment on a clean implementation of controlling of the CAAM clock.

Signed-off-by: Henri Roosen <henri.roosen at ginzinger.com>
---
 arch/arm/imx-common/cmd_dek.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/arch/arm/imx-common/cmd_dek.c b/arch/arm/imx-common/cmd_dek.c
index ada8adf..72a7d49 100644
--- a/arch/arm/imx-common/cmd_dek.c
+++ b/arch/arm/imx-common/cmd_dek.c
@@ -30,20 +30,22 @@ static int blob_encap_dek(const u8 *src, u8 *dst, u32 len)
 {
 	int ret = 0;
 	u32 jr_size = 4;
-
-	u32 out_jr_size = sec_in32(CONFIG_SYS_FSL_JR0_ADDR + 0x102c);
-	if (out_jr_size != jr_size) {
-		hab_caam_clock_enable(1);
-		sec_init();
-	}
+	u32 out_jr_size;
 
 	if (!((len == 128) | (len == 192) | (len == 256))) {
 		debug("Invalid DEK size. Valid sizes are 128, 192 and 256b\n");
 		return -1;
 	}
 
+	hab_caam_clock_enable(1);
+	out_jr_size = sec_in32(CONFIG_SYS_FSL_JR0_ADDR + 0x102c);
+	if (out_jr_size != jr_size) {
+		sec_init();
+	}
+
 	len /= 8;
 	ret = blob_dek(src, dst, len);
+	hab_caam_clock_enable(0);
 
 	return ret;
 }
-- 
2.1.4