diff options
Diffstat (limited to 'arch/x86/kernel/apic/probe_32.c')
| -rw-r--r-- | arch/x86/kernel/apic/probe_32.c | 209 |
1 files changed, 209 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..a61f642b1 --- /dev/null +++ b/arch/x86/kernel/apic/probe_32.c @@ -0,0 +1,209 @@ +// 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, + + .delivery_mode = APIC_DELIVERY_MODE_FIXED, + .dest_mode_logical = true, + + .disable_esr = 0, + + .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; +} |