@@ -165,7 +165,7 @@ multipliers 'Kilo', 'Mega', and 'Giga', equalling 2^10, 2^20, and 2^30
bytes respectively. Such letter suffixes can also be entirely omitted.
- acpi= [HW,ACPI,X86]
+ acpi= [HW,ACPI,X86,ARM64]
Advanced Configuration and Power Interface
Format: { force | off | strict | noirq | rsdt }
force -- enable ACPI if default was off
@@ -175,6 +175,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
strictly ACPI specification compliant.
rsdt -- prefer RSDT over (default) XSDT
copy_dsdt -- copy DSDT to memory
+ For ARM64, ONLY "acpi=off" or "acpi=force" are available
See also Documentation/power/runtime_pm.txt, pci=noacpi
@@ -39,6 +39,13 @@ static inline void disable_acpi(void)
acpi_noirq = 1;
}
+static inline void enable_acpi(void)
+{
+ acpi_disabled = 0;
+ acpi_pci_disabled = 0;
+ acpi_noirq = 0;
+}
+
/*
* It's used from ACPI core in kdump to boot UP system with SMP kernel,
* with this check the ACPI core will not override the CPU index
@@ -22,15 +22,49 @@
#include <linux/irq.h>
#include <linux/irqdomain.h>
#include <linux/memblock.h>
+#include <linux/of_fdt.h>
#include <linux/smp.h>
-int acpi_noirq; /* skip ACPI IRQ initialization */
-int acpi_disabled;
+int acpi_noirq = 1; /* skip ACPI IRQ initialization */
+int acpi_disabled = 1;
EXPORT_SYMBOL(acpi_disabled);
-int acpi_pci_disabled; /* skip ACPI PCI scan and IRQ initialization */
+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_force __initdata;
+
+static int __init parse_acpi(char *arg)
+{
+ if (!arg)
+ return -EINVAL;
+
+ /* "acpi=off" disables both ACPI table parsing and interpreter */
+ if (strcmp(arg, "off") == 0)
+ param_acpi_off = true;
+ else if (strcmp(arg, "force") == 0) /* force ACPI to be enabled */
+ param_acpi_force = true;
+ else
+ return -EINVAL; /* Core will print when we return error */
+
+ return 0;
+}
+early_param("acpi", parse_acpi);
+
+static int __init dt_scan_depth1_nodes(unsigned long node,
+ const char *uname, int depth,
+ void *data)
+{
+ /*
+ * Return 1 as soon as we encounter a node at depth 1 that is
+ * not the /chosen node.
+ */
+ if (depth == 1 && (strcmp(uname, "chosen") != 0))
+ return 1;
+ return 0;
+}
+
/*
* __acpi_map_table() will be called before page_init(), so early_ioremap()
* or early_memremap() should be called here to for ACPI table mapping.
@@ -83,10 +117,18 @@ static int __init acpi_parse_fadt(struct acpi_table_header *table)
*/
void __init acpi_boot_table_init(void)
{
- /* If acpi_disabled, bail out */
- if (acpi_disabled)
+ /*
+ * 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)
+ */
+ if (param_acpi_off ||
+ (!param_acpi_force && of_scan_flat_dt(dt_scan_depth1_nodes, NULL)))
return;
+ enable_acpi();
+
/* Initialize the ACPI boot-time table parser. */
if (acpi_table_init()) {
disable_acpi();