feat(versal): ddr address reservation in dtb at runtime
When the TF-A is placed in DDR memory range, the DDR memory range
needs to be explicitly reserved in the default device tree.
A new build time parameter, XILINX_OF_BOARD_DTB_ADDR, is introduced.
The TF-A will reserve the DDR memory only when a valid DTB address
is provided to XILINX_OF_BOARD_DTB_ADDR during build.
Now the user has options, either manually reserve the desired DDR
address range for TF-A in device tree or let TF-A access and modify
the device tree, to reserve the DDR address range, in runtime using
the build parameter.
Change-Id: I4442a90e1cab5a3a115f4eeb8a7e09e247189ff0
Signed-off-by: Amit Nagal <amit.nagal@amd.com>
Signed-off-by: Akshay Belsare <akshay.belsare@amd.com>
diff --git a/plat/xilinx/common/include/plat_fdt.h b/plat/xilinx/common/include/plat_fdt.h
new file mode 100644
index 0000000..a1ee1e1
--- /dev/null
+++ b/plat/xilinx/common/include/plat_fdt.h
@@ -0,0 +1,12 @@
+/*
+ * Copyright (c) 2023, Advanced Micro Devices, Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ */
+#ifndef PLAT_FDT_H
+#define PLAT_FDT_H
+
+void prepare_dtb(void);
+
+#endif /* PLAT_FDT_H */
diff --git a/plat/xilinx/common/plat_fdt.c b/plat/xilinx/common/plat_fdt.c
new file mode 100644
index 0000000..3d12d51
--- /dev/null
+++ b/plat/xilinx/common/plat_fdt.c
@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) 2023, Advanced Micro Devices, Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ */
+#include <common/fdt_fixup.h>
+#include <common/fdt_wrappers.h>
+
+#include <plat_fdt.h>
+#include <platform_def.h>
+
+#if (defined(XILINX_OF_BOARD_DTB_ADDR) && !IS_TFA_IN_OCM(BL31_BASE))
+void prepare_dtb(void)
+{
+ void *dtb = (void *)XILINX_OF_BOARD_DTB_ADDR;
+ int ret;
+
+ /* Return if no device tree is detected */
+ if (fdt_check_header(dtb) != 0) {
+ NOTICE("Can't read DT at %p\n", dtb);
+ return;
+ }
+
+ ret = fdt_open_into(dtb, dtb, XILINX_OF_BOARD_DTB_MAX_SIZE);
+ if (ret < 0) {
+ ERROR("Invalid Device Tree at %p: error %d\n", dtb, ret);
+ return;
+ }
+
+ /* Reserve memory used by Trusted Firmware. */
+ if (fdt_add_reserved_memory(dtb, "tf-a", BL31_BASE, BL31_LIMIT - BL31_BASE + 1)) {
+ WARN("Failed to add reserved memory nodes for BL31 to DT.\n");
+ return;
+ }
+
+ ret = fdt_pack(dtb);
+ if (ret < 0) {
+ ERROR("Failed to pack Device Tree at %p: error %d\n", dtb, ret);
+ return;
+ }
+
+ clean_dcache_range((uintptr_t)dtb, fdt_blob_size(dtb));
+ INFO("Changed device tree to advertise PSCI and reserved memories.\n");
+}
+#else
+void prepare_dtb(void)
+{
+}
+#endif