firmware: zynqmp: Report error when xilinx_pm_request called from EL3

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

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

diff --git a/drivers/firmware/firmware-zynqmp.c b/drivers/firmware/firmware-zynqmp.c
index adcef15e22aa115e719e6b27a4872cbc9c73c935..4911734f6c6342ea2ff6e81d6d4df8574dd52085 100644 (file)
--- 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;