diff options
Diffstat (limited to 'arch/arm64/kernel/acpi.c')
| -rw-r--r-- | arch/arm64/kernel/acpi.c | 33 |
1 files changed, 25 insertions, 8 deletions
diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c index d1ce8e2f98b9..3e4f1a45b125 100644 --- a/arch/arm64/kernel/acpi.c +++ b/arch/arm64/kernel/acpi.c @@ -42,6 +42,7 @@ int acpi_pci_disabled = 1; /* skip ACPI PCI scan and IRQ initialization */ EXPORT_SYMBOL(acpi_pci_disabled); static bool param_acpi_off __initdata; +static bool param_acpi_on __initdata; static bool param_acpi_force __initdata; static int __init parse_acpi(char *arg) @@ -52,6 +53,8 @@ static int __init parse_acpi(char *arg) /* "acpi=off" disables both ACPI table parsing and interpreter */ if (strcmp(arg, "off") == 0) param_acpi_off = true; + else if (strcmp(arg, "on") == 0) /* prefer ACPI over DT */ + param_acpi_on = true; else if (strcmp(arg, "force") == 0) /* force ACPI to be enabled */ param_acpi_force = true; else @@ -66,12 +69,24 @@ static int __init dt_scan_depth1_nodes(unsigned long node, void *data) { /* - * Return 1 as soon as we encounter a node at depth 1 that is - * not the /chosen node. + * Ignore anything not directly under the root node; we'll + * catch its parent instead. */ - if (depth == 1 && (strcmp(uname, "chosen") != 0)) - return 1; - return 0; + if (depth != 1) + return 0; + + if (strcmp(uname, "chosen") == 0) + return 0; + + if (strcmp(uname, "hypervisor") == 0 && + of_flat_dt_is_compatible(node, "xen,xen")) + return 0; + + /* + * This node at depth 1 is neither a chosen node nor a xen node, + * which we do not expect. + */ + return 1; } /* @@ -184,11 +199,13 @@ void __init acpi_boot_table_init(void) /* * Enable ACPI instead of device tree unless * - ACPI has been disabled explicitly (acpi=off), or - * - the device tree is not empty (it has more than just a /chosen node) - * and ACPI has not been force enabled (acpi=force) + * - the device tree is not empty (it has more than just a /chosen node, + * and a /hypervisor node when running on Xen) + * and ACPI has not been [force] enabled (acpi=on|force) */ if (param_acpi_off || - (!param_acpi_force && of_scan_flat_dt(dt_scan_depth1_nodes, NULL))) + (!param_acpi_on && !param_acpi_force && + of_scan_flat_dt(dt_scan_depth1_nodes, NULL))) return; /* |