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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /arch/x86/kernel/apic/apic_noop.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/kernel/apic/apic_noop.c')
-rw-r--r--arch/x86/kernel/apic/apic_noop.c141
1 files changed, 141 insertions, 0 deletions
diff --git a/arch/x86/kernel/apic/apic_noop.c b/arch/x86/kernel/apic/apic_noop.c
new file mode 100644
index 000000000..fe78319e0
--- /dev/null
+++ b/arch/x86/kernel/apic/apic_noop.c
@@ -0,0 +1,141 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * NOOP APIC driver.
+ *
+ * Does almost nothing and should be substituted by a real apic driver via
+ * probe routine.
+ *
+ * Though in case if apic is disabled (for some reason) we try
+ * to not uglify the caller's code and allow to call (some) apic routines
+ * like self-ipi, etc...
+ */
+#include <linux/cpumask.h>
+#include <linux/thread_info.h>
+
+#include <asm/apic.h>
+
+static void noop_init_apic_ldr(void) { }
+static void noop_send_IPI(int cpu, int vector) { }
+static void noop_send_IPI_mask(const struct cpumask *cpumask, int vector) { }
+static void noop_send_IPI_mask_allbutself(const struct cpumask *cpumask, int vector) { }
+static void noop_send_IPI_allbutself(int vector) { }
+static void noop_send_IPI_all(int vector) { }
+static void noop_send_IPI_self(int vector) { }
+static void noop_apic_wait_icr_idle(void) { }
+static void noop_apic_icr_write(u32 low, u32 id) { }
+
+static int noop_wakeup_secondary_cpu(int apicid, unsigned long start_eip)
+{
+ return -1;
+}
+
+static u32 noop_safe_apic_wait_icr_idle(void)
+{
+ return 0;
+}
+
+static u64 noop_apic_icr_read(void)
+{
+ return 0;
+}
+
+static int noop_phys_pkg_id(int cpuid_apic, int index_msb)
+{
+ return 0;
+}
+
+static unsigned int noop_get_apic_id(unsigned long x)
+{
+ return 0;
+}
+
+static int noop_probe(void)
+{
+ /*
+ * NOOP apic should not ever be
+ * enabled via probe routine
+ */
+ return 0;
+}
+
+static int noop_apic_id_registered(void)
+{
+ /*
+ * if we would be really "pedantic"
+ * we should pass read_apic_id() here
+ * but since NOOP suppose APIC ID = 0
+ * lets save a few cycles
+ */
+ return physid_isset(0, phys_cpu_present_map);
+}
+
+static u32 noop_apic_read(u32 reg)
+{
+ WARN_ON_ONCE(boot_cpu_has(X86_FEATURE_APIC) && !disable_apic);
+ return 0;
+}
+
+static void noop_apic_write(u32 reg, u32 v)
+{
+ WARN_ON_ONCE(boot_cpu_has(X86_FEATURE_APIC) && !disable_apic);
+}
+
+#ifdef CONFIG_X86_32
+static int noop_x86_32_early_logical_apicid(int cpu)
+{
+ return BAD_APICID;
+}
+#endif
+
+struct apic apic_noop __ro_after_init = {
+ .name = "noop",
+ .probe = noop_probe,
+ .acpi_madt_oem_check = NULL,
+
+ .apic_id_valid = default_apic_id_valid,
+ .apic_id_registered = noop_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 = noop_init_apic_ldr,
+ .ioapic_phys_id_map = default_ioapic_phys_id_map,
+ .setup_apic_routing = NULL,
+ .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 = noop_phys_pkg_id,
+
+ .get_apic_id = noop_get_apic_id,
+ .set_apic_id = NULL,
+
+ .calc_dest_apicid = apic_flat_calc_apicid,
+
+ .send_IPI = noop_send_IPI,
+ .send_IPI_mask = noop_send_IPI_mask,
+ .send_IPI_mask_allbutself = noop_send_IPI_mask_allbutself,
+ .send_IPI_allbutself = noop_send_IPI_allbutself,
+ .send_IPI_all = noop_send_IPI_all,
+ .send_IPI_self = noop_send_IPI_self,
+
+ .wakeup_secondary_cpu = noop_wakeup_secondary_cpu,
+
+ .inquire_remote_apic = NULL,
+
+ .read = noop_apic_read,
+ .write = noop_apic_write,
+ .eoi_write = noop_apic_write,
+ .icr_read = noop_apic_icr_read,
+ .icr_write = noop_apic_icr_write,
+ .wait_icr_idle = noop_apic_wait_icr_idle,
+ .safe_wait_icr_idle = noop_safe_apic_wait_icr_idle,
+
+#ifdef CONFIG_X86_32
+ .x86_32_early_logical_apicid = noop_x86_32_early_logical_apicid,
+#endif
+};