handle /reserved-memory nodes from device trees on arm64.

u-boot is supposed to take these entries and put them in the efi
memory map, but i keep hitting machines where an otherwise functional
u-boot does not do this, resulting in weird errors.

i have an espressobin with a vendor u-boot that has a reserved-memory
region for psci. without this diff the machine faults when the
kernel tries to reboot using a psci handler.

a macchiatobin with an otherwise working u-boot throws SErrors or
panics on weird memory corruption problems without this. i thought
it was bad RAM, but the problems persisted with completely different
ram, and very underclocked and well cooled ram.

riscv64 already has code to handle reserved-memory regions. the
riscv64 change is to add handling for the "no-map" property.

ok kettenis@

diff --git a/sys/arch/arm64/arm64/machdep.c b/sys/arch/arm64/arm64/machdep.c
index 69dc76a..fc1df71 100644 (file)
--- a/sys/arch/arm64/arm64/machdep.c
+++ b/sys/arch/arm64/arm64/machdep.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: machdep.c,v 1.85 2023/12/04 15:00:09 claudio Exp $ */
+/* $OpenBSD: machdep.c,v 1.86 2024/02/21 01:45:14 dlg Exp $ */
 /*
  * Copyright (c) 2014 Patrick Wildt <patrick@blueri.se>
  * Copyright (c) 2021 Mark Kettenis <kettenis@openbsd.org>
@@ -1053,6 +1053,22 @@ initarm(struct arm64_bootparams *abp)
                }
        }
 
+       /* Remove reserved memory. */
+       node = fdt_find_node("/reserved-memory");
+       if (node) {
+               for (node = fdt_child_node(node); node;
+                   node = fdt_next_node(node)) {
+                       char *no_map;
+                       if (fdt_node_property(node, "no-map", &no_map) < 0)
+                               continue;
+                       if (fdt_get_reg(node, 0, &reg))
+                               continue;
+                       if (reg.size == 0)
+                               continue;
+                       memreg_remove(&reg);
+               }
+       }
+
        /* Remove the initial 64MB block. */
        reg.addr = memstart;
        reg.size = memend - memstart;

diff --git a/sys/arch/riscv64/riscv64/machdep.c b/sys/arch/riscv64/riscv64/machdep.c
index 7658ba0..1141cd2 100644 (file)
--- a/sys/arch/riscv64/riscv64/machdep.c
+++ b/sys/arch/riscv64/riscv64/machdep.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: machdep.c,v 1.34 2024/01/23 19:51:10 kettenis Exp $   */
+/*     $OpenBSD: machdep.c,v 1.35 2024/02/21 01:45:14 dlg Exp $        */
 
 /*
  * Copyright (c) 2014 Patrick Wildt <patrick@blueri.se>
@@ -792,6 +792,9 @@ initriscv(struct riscv_bootparams *rbp)
        if (node) {
                for (node = fdt_child_node(node); node;
                    node = fdt_next_node(node)) {
+                       char *no_map;
+                       if (fdt_node_property(node, "no-map", &no_map) < 0)
+                               continue;
                        if (fdt_get_reg(node, 0, &reg))
                                continue;
                        if (reg.size == 0)