Detect SCP version incompatibility
There has been a breaking change in the communication protocols used
between the AP cores and the SCP on CSS based platforms like Juno.
This means both the AP Trusted Firmware and SCP firmware must be
updated at the same time.
In case the user forgets to update the SCP ROM firmware, this patch
detects when it still uses the previous version of the communication
protocol. It will then output a comprehensive error message that helps
trouble-shoot the issue.
Change-Id: I7baf8f05ec0b7d8df25e0ee53df61fe7be0207c2
diff --git a/plat/arm/css/common/css_common.mk b/plat/arm/css/common/css_common.mk
index edbfe1e..1b0404b 100644
--- a/plat/arm/css/common/css_common.mk
+++ b/plat/arm/css/common/css_common.mk
@@ -53,3 +53,11 @@
endif
NEED_BL30 := yes
+
+# Enable option to detect whether the SCP ROM firmware in use predates version
+# 1.7.0 and therefore, is incompatible.
+CSS_DETECT_PRE_1_7_0_SCP := 1
+
+# Process CSS_DETECT_PRE_1_7_0_SCP flag
+$(eval $(call assert_boolean,CSS_DETECT_PRE_1_7_0_SCP))
+$(eval $(call add_define,CSS_DETECT_PRE_1_7_0_SCP))
diff --git a/plat/arm/css/common/css_scp_bootloader.c b/plat/arm/css/common/css_scp_bootloader.c
index c6d63f2..6cf1667 100644
--- a/plat/arm/css/common/css_scp_bootloader.c
+++ b/plat/arm/css/common/css_scp_bootloader.c
@@ -148,6 +148,24 @@
cmd_info_payload->checksum = checksum;
scp_boot_message_send(sizeof(*cmd_info_payload));
+#if CSS_DETECT_PRE_1_7_0_SCP
+ {
+ const uint32_t deprecated_scp_nack_cmd = 0x404;
+ uint32_t mhu_status;
+
+ VERBOSE("Detecting SCP version incompatibility\n");
+
+ mhu_status = mhu_secure_message_wait();
+ if (mhu_status == deprecated_scp_nack_cmd) {
+ ERROR("Detected an incompatible version of the SCP firmware.\n");
+ ERROR("Only versions from v1.7.0 onwards are supported.\n");
+ ERROR("Please update the SCP firmware.\n");
+ return -1;
+ }
+
+ VERBOSE("SCP version looks OK\n");
+ }
+#endif /* CSS_DETECT_PRE_1_7_0_SCP */
response = scp_boot_message_wait(sizeof(response));
scp_boot_message_end();