summaryrefslogtreecommitdiffstats
path: root/arch/x86/kernel/apic/probe_32.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kernel/apic/probe_32.c')
-rw-r--r--arch/x86/kernel/apic/probe_32.c212
1 files changed, 212 insertions, 0 deletions
diff --git a/arch/x86/kernel/apic/probe_32.c b/arch/x86/kernel/apic/probe_32.c
new file mode 100644
index 000000000..67b6f7c04
--- /dev/null
+++ b/arch/x86/kernel/apic/probe_32.c
@@ -0,0 +1,212 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Default generic APIC driver. This handles up to 8 CPUs.
+ *
+ * Copyright 2003 Andi Kleen, SuSE Labs.
+ *
+ * Generic x86 APIC driver probe layer.
+ */
+#include <linux/export.h>
+#include <linux/errno.h>
+#include <linux/smp.h>
+
+#include <asm/io_apic.h>
+#include <asm/apic.h>
+#include <asm/acpi.h>
+
+#include "local.h"
+
+static int default_x86_32_early_logical_apicid(int cpu)
+{
+ return 1 << cpu;
+}
+
+static void setup_apic_flat_routing(void)
+{
+#ifdef CONFIG_X86_IO_APIC
+ printk(KERN_INFO
+ "Enabling APIC mode: Flat. Using %d I/O APICs\n",
+ nr_ioapics);
+#endif
+}
+
+static int default_apic_id_registered(void)
+{
+ return physid_isset(read_apic_id(), phys_cpu_present_map);
+}
+
+/*
+ * Set up the logical destination ID. Intel recommends to set DFR, LDR and
+ * TPR before enabling an APIC. See e.g. "AP-388 82489DX User's Manual"
+ * (Intel document number 292116).
+ */
+static void default_init_apic_ldr(void)
+{
+ unsigned long val;
+
+ apic_write(APIC_DFR, APIC_DFR_VALUE);
+ val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
+ val |= SET_APIC_LOGICAL_ID(1UL << smp_processor_id());
+ apic_write(APIC_LDR, val);
+}
+
+static int default_phys_pkg_id(int cpuid_apic, int index_msb)
+{
+ return cpuid_apic >> index_msb;
+}
+
+/* should be called last. */
+static int probe_default(void)
+{
+ return 1;
+}
+
+static struct apic apic_default __ro_after_init = {
+
+ .name = "default",
+ .probe = probe_default,
+ .acpi_madt_oem_check = NULL,
+ .apic_id_valid = default_apic_id_valid,
+ .apic_id_registered = default_apic_id_registered,
+
+ .irq_delivery_mode = dest_Fixed,
+ /* logical delivery broadcast to all CPUs: */
+ .irq_dest_mode = 1,
+
+ .disable_esr = 0,
+ .dest_logical = APIC_DEST_LOGICAL,
+ .check_apicid_used = default_check_apicid_used,
+
+ .init_apic_ldr = default_init_apic_ldr,
+
+ .ioapic_phys_id_map = default_ioapic_phys_id_map,
+ .setup_apic_routing = setup_apic_flat_routing,
+ .cpu_present_to_apicid = default_cpu_present_to_apicid,
+ .apicid_to_cpu_present = physid_set_mask_of_physid,
+ .check_phys_apicid_present = default_check_phys_apicid_present,
+ .phys_pkg_id = default_phys_pkg_id,
+
+ .get_apic_id = default_get_apic_id,
+ .set_apic_id = NULL,
+
+ .calc_dest_apicid = apic_flat_calc_apicid,
+
+ .send_IPI = default_send_IPI_single,
+ .send_IPI_mask = default_send_IPI_mask_logical,
+ .send_IPI_mask_allbutself = default_send_IPI_mask_allbutself_logical,
+ .send_IPI_allbutself = default_send_IPI_allbutself,
+ .send_IPI_all = default_send_IPI_all,
+ .send_IPI_self = default_send_IPI_self,
+
+ .inquire_remote_apic = default_inquire_remote_apic,
+
+ .read = native_apic_mem_read,
+ .write = native_apic_mem_write,
+ .eoi_write = native_apic_mem_write,
+ .icr_read = native_apic_icr_read,
+ .icr_write = native_apic_icr_write,
+ .wait_icr_idle = native_apic_wait_icr_idle,
+ .safe_wait_icr_idle = native_safe_apic_wait_icr_idle,
+
+ .x86_32_early_logical_apicid = default_x86_32_early_logical_apicid,
+};
+
+apic_driver(apic_default);
+
+struct apic *apic __ro_after_init = &apic_default;
+EXPORT_SYMBOL_GPL(apic);
+
+static int cmdline_apic __initdata;
+static int __init parse_apic(char *arg)
+{
+ struct apic **drv;
+
+ if (!arg)
+ return -EINVAL;
+
+ for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
+ if (!strcmp((*drv)->name, arg)) {
+ apic = *drv;
+ cmdline_apic = 1;
+ return 0;
+ }
+ }
+
+ /* Parsed again by __setup for debug/verbose */
+ return 0;
+}
+early_param("apic", parse_apic);
+
+void __init default_setup_apic_routing(void)
+{
+ int version = boot_cpu_apic_version;
+
+ if (num_possible_cpus() > 8) {
+ switch (boot_cpu_data.x86_vendor) {
+ case X86_VENDOR_INTEL:
+ if (!APIC_XAPIC(version)) {
+ def_to_bigsmp = 0;
+ break;
+ }
+ /* P4 and above */
+ fallthrough;
+ case X86_VENDOR_HYGON:
+ case X86_VENDOR_AMD:
+ def_to_bigsmp = 1;
+ }
+ }
+
+#ifdef CONFIG_X86_BIGSMP
+ /*
+ * This is used to switch to bigsmp mode when
+ * - There is no apic= option specified by the user
+ * - generic_apic_probe() has chosen apic_default as the sub_arch
+ * - we find more than 8 CPUs in acpi LAPIC listing with xAPIC support
+ */
+
+ if (!cmdline_apic && apic == &apic_default)
+ generic_bigsmp_probe();
+#endif
+
+ if (apic->setup_apic_routing)
+ apic->setup_apic_routing();
+}
+
+void __init generic_apic_probe(void)
+{
+ if (!cmdline_apic) {
+ struct apic **drv;
+
+ for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
+ if ((*drv)->probe()) {
+ apic = *drv;
+ break;
+ }
+ }
+ /* Not visible without early console */
+ if (drv == __apicdrivers_end)
+ panic("Didn't find an APIC driver");
+ }
+ printk(KERN_INFO "Using APIC driver %s\n", apic->name);
+}
+
+/* This function can switch the APIC even after the initial ->probe() */
+int __init default_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
+{
+ struct apic **drv;
+
+ for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
+ if (!(*drv)->acpi_madt_oem_check)
+ continue;
+ if (!(*drv)->acpi_madt_oem_check(oem_id, oem_table_id))
+ continue;
+
+ if (!cmdline_apic) {
+ apic = *drv;
+ printk(KERN_INFO "Switched to APIC driver `%s'.\n",
+ apic->name);
+ }
+ return 1;
+ }
+ return 0;
+}