- apbmisc_base = of_iomap(np, 0);
- if (!apbmisc_base) {
- pr_warn("ioremap tegra apbmisc failed. using %08x instead\n",
- APBMISC_BASE);
- apbmisc_base = ioremap(APBMISC_BASE, APBMISC_SIZE);
+ if (!np) {
+ /*
+ * Fall back to legacy initialization for 32-bit ARM only. All
+ * 64-bit ARM device tree files for Tegra are required to have
+ * an APBMISC node.
+ *
+ * This is for backwards-compatibility with old device trees
+ * that didn't contain an APBMISC node.
+ */
+ if (IS_ENABLED(CONFIG_ARM) && soc_is_tegra()) {
+ /* APBMISC registers (chip revision, ...) */
+ apbmisc.start = 0x70000800;
+ apbmisc.end = 0x70000863;
+ apbmisc.flags = IORESOURCE_MEM;
+
+ /* strapping options */
+ if (tegra_get_chip_id() == TEGRA124) {
+ straps.start = 0x7000e864;
+ straps.end = 0x7000e867;
+ } else {
+ straps.start = 0x70000008;
+ straps.end = 0x7000000b;
+ }
+
+ straps.flags = IORESOURCE_MEM;
+
+ pr_warn("Using APBMISC region %pR\n", &apbmisc);
+ pr_warn("Using strapping options registers %pR\n",
+ &straps);
+ } else {
+ /*
+ * At this point we're not running on Tegra, so play
+ * nice with multi-platform kernels.
+ */
+ return;
+ }
+ } else {
+ /*
+ * Extract information from the device tree if we've found a
+ * matching node.
+ */
+ if (of_address_to_resource(np, 0, &apbmisc) < 0) {
+ pr_err("failed to get APBMISC registers\n");
+ return;
+ }
+
+ if (of_address_to_resource(np, 1, &straps) < 0) {
+ pr_err("failed to get strapping options registers\n");
+ return;
+ }