[U-Boot] [PATCH] firmware: zynqmp: Report error when xilinx_pm_request called from EL3

[Michal Simek]

Function should report error when called in EL3 context. Also report it as
error instead 0 (success).

Reported-by: Luca Ceresoli <luca at lucaceresoli.net>
Signed-off-by: Michal Simek <michal.simek at xilinx.com>
---

Based on https://lists.denx.de/pipermail/u-boot/2019-October/385462.html
series.
---
 drivers/firmware/firmware-zynqmp.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/firmware-zynqmp.c b/drivers/firmware/firmware-zynqmp.c
index adcef15e22aa..4911734f6c63 100644
--- a/drivers/firmware/firmware-zynqmp.c
+++ b/drivers/firmware/firmware-zynqmp.c
@@ -156,8 +156,10 @@ int __maybe_unused xilinx_pm_request(u32 api_id, u32 arg0, u32 arg1, u32 arg2,
 	 */
 	struct pt_regs regs;
 
-	if (current_el() == 3)
-		return 0;
+	if (current_el() == 3) {
+		printf("%s: Can't call SMC from EL3 context\n", __func__);
+		return -EPERM;
+	}
 
 	regs.regs[0] = PM_SIP_SVC | api_id;
 	regs.regs[1] = ((u64)arg1 << 32) | arg0;
-- 
2.17.1