@@ -2653,6 +2653,11 @@ int xc_livepatch_replace(xc_interface *xch, char *name, uint32_t timeout, uint32
int xc_domain_cacheflush(xc_interface *xch, uint32_t domid,
xen_pfn_t start_pfn, xen_pfn_t nr_pfns);
+#if defined(__arm__) || defined(__aarch64__)
+int xc_dt_overlay(xc_interface *xch, void *overlay_fdt,
+ uint32_t overlay_fdt_size, uint8_t overlay_op);
+#endif
+
/* Compat shims */
#include "xenctrl_compat.h"
@@ -24,6 +24,7 @@ OBJS-y += xc_hcall_buf.o
OBJS-y += xc_foreign_memory.o
OBJS-y += xc_kexec.o
OBJS-y += xc_resource.o
+OBJS-$(CONFIG_ARM) += xc_dt_overlay.o
OBJS-$(CONFIG_X86) += xc_psr.o
OBJS-$(CONFIG_X86) += xc_pagetab.o
OBJS-$(CONFIG_Linux) += xc_linux.o
new file mode 100644
@@ -0,0 +1,50 @@
+/*
+ *
+ * Device Tree Overlay functions.
+ * Copyright (C) 2021 Xilinx Inc.
+ * Author Vikram Garhwal <fnu.vikram@xilinx.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "xc_private.h"
+
+int xc_dt_overlay(xc_interface *xch, void *overlay_fdt,
+ uint32_t overlay_fdt_size, uint8_t overlay_op)
+{
+ int err;
+ struct xen_sysctl sysctl = {
+ .cmd = XEN_SYSCTL_dt_overlay,
+ .u.dt_overlay = {
+ .overlay_op = overlay_op,
+ .overlay_fdt_size = overlay_fdt_size,
+ }
+ };
+
+ DECLARE_HYPERCALL_BOUNCE(overlay_fdt, overlay_fdt_size,
+ XC_HYPERCALL_BUFFER_BOUNCE_IN);
+
+ if ( (err = xc_hypercall_bounce_pre(xch, overlay_fdt)) )
+ goto err;
+
+ set_xen_guest_handle(sysctl.u.dt_overlay.overlay_fdt, overlay_fdt);
+
+ if ( (err = do_sysctl(xch, &sysctl)) != 0 )
+ PERROR("%s failed", __func__);
+
+err:
+ xc_hypercall_bounce_post(xch, overlay_fdt);
+
+ return err;
+}