git: 083a2ff0f032 - stable/13 - acpi_cpu: Make device unit numbers match OS CPU IDs.

From: Alexander Motin <mav_at_FreeBSD.org>
Date: Tue, 04 Jan 2022 18:03:27 UTC
The branch stable/13 has been updated by mav:

URL: https://cgit.FreeBSD.org/src/commit/?id=083a2ff0f0328199bc79eee82e301c7896cb58ff

commit 083a2ff0f0328199bc79eee82e301c7896cb58ff
Author:     Alexander Motin <mav@FreeBSD.org>
AuthorDate: 2021-09-25 01:03:02 +0000
Commit:     Alexander Motin <mav@FreeBSD.org>
CommitDate: 2022-01-04 17:21:35 +0000

    acpi_cpu: Make device unit numbers match OS CPU IDs.
    
    There are already APIC ID, ACPI ID and OS ID for each CPU.  In perfect
    world all of those may match, but at least for SuperMicro server boards
    none of them do.  Plus none of them match the CPU devices listing order
    by ACPI.  Previous code used the ACPI device listing order to number
    cpuX devices.  It looked nice from NewBus perspective, but introduced
    4th different set of IDs. Extremely confusing one, since in some places
    the device unit numbers were treated as OS CPU IDs (coretemp), but not
    in others (sysctl dev.cpu.X.%location).
    
    (cherry picked from commit c8077ccd70cfcbcccb752e89b848f098abcb9309)
---
 share/man/man4/acpi.4     |  7 +---
 sys/dev/acpica/acpi_cpu.c | 83 ++++++++++++-----------------------------------
 2 files changed, 22 insertions(+), 68 deletions(-)

diff --git a/share/man/man4/acpi.4 b/share/man/man4/acpi.4
index 0a865d9e7a38..7a71e7668e4b 100644
--- a/share/man/man4/acpi.4
+++ b/share/man/man4/acpi.4
@@ -25,7 +25,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd October 12, 2021
+.Dd September 24, 2021
 .Dt ACPI 4
 .Os
 .Sh NAME
@@ -207,11 +207,6 @@ entry for access after boot.
 Enables loading of a custom ACPI DSDT.
 .It Va acpi_dsdt_name
 Name of the DSDT table to load, if loading is enabled.
-.It Va debug.acpi.cpu_unordered
-Do not use the MADT to match ACPI Processor objects to CPUs.
-This is needed on a few systems with a buggy BIOS that does not use
-consistent processor IDs.
-Default is 0 (disabled).
 .It Va debug.acpi.disabled
 Selectively disables portions of ACPI for debugging purposes.
 .It Va debug.acpi.interpreter_slack
diff --git a/sys/dev/acpica/acpi_cpu.c b/sys/dev/acpica/acpi_cpu.c
index 3c81d55436ca..ab4ffda7a02e 100644
--- a/sys/dev/acpica/acpi_cpu.c
+++ b/sys/dev/acpica/acpi_cpu.c
@@ -140,12 +140,6 @@ struct acpi_cpu_device {
 
 #define	CPUDEV_DEVICE_ID	"ACPI0007"
 
-/* Allow users to ignore processor orders in MADT. */
-static int cpu_unordered;
-SYSCTL_INT(_debug_acpi, OID_AUTO, cpu_unordered, CTLFLAG_RDTUN,
-    &cpu_unordered, 0,
-    "Do not use the MADT to match ACPI Processor objects to CPUs.");
-
 /* Knob to disable acpi_cpu devices */
 bool acpi_cpu_disabled = false;
 
@@ -169,8 +163,8 @@ static int	acpi_cpu_probe(device_t dev);
 static int	acpi_cpu_attach(device_t dev);
 static int	acpi_cpu_suspend(device_t dev);
 static int	acpi_cpu_resume(device_t dev);
-static int	acpi_pcpu_get_id(device_t dev, uint32_t *acpi_id,
-		    uint32_t *cpu_id);
+static int	acpi_pcpu_get_id(device_t dev, uint32_t acpi_id,
+		    u_int *cpu_id);
 static struct resource_list *acpi_cpu_get_rlist(device_t dev, device_t child);
 static device_t	acpi_cpu_add_child(device_t dev, u_int order, const char *name,
 		    int unit);
@@ -291,19 +285,16 @@ acpi_cpu_probe(device_t dev)
 	    return (ENXIO);
 	}
     }
-    if (acpi_pcpu_get_id(dev, &acpi_id, &cpu_id) != 0)
+    if (acpi_pcpu_get_id(dev, acpi_id, &cpu_id) != 0) {
+	if (bootverbose && (type != ACPI_TYPE_PROCESSOR || acpi_id != 255))
+	    printf("ACPI: Processor %s (ACPI ID %u) ignored\n",
+		acpi_name(acpi_get_handle(dev)), acpi_id);
 	return (ENXIO);
+    }
 
-    /*
-     * Check if we already probed this processor.  We scan the bus twice
-     * so it's possible we've already seen this one.
-     */
-    if (cpu_softc[cpu_id] != NULL)
+    if (device_set_unit(dev, cpu_id) != 0)
 	return (ENXIO);
 
-    /* Mark this processor as in-use and save our derived id for attach. */
-    cpu_softc[cpu_id] = (void *)1;
-    acpi_set_private(dev, (void*)(intptr_t)cpu_id);
     device_set_desc(dev, "ACPI CPU");
 
     if (!bootverbose && device_get_unit(dev) != 0) {
@@ -339,7 +330,7 @@ acpi_cpu_attach(device_t dev)
     sc = device_get_softc(dev);
     sc->cpu_dev = dev;
     sc->cpu_handle = acpi_get_handle(dev);
-    cpu_id = (int)(intptr_t)acpi_get_private(dev);
+    cpu_id = device_get_unit(dev);
     cpu_softc[cpu_id] = sc;
     pcpu_data = pcpu_find(cpu_id);
     pcpu_data->pc_device = dev;
@@ -546,66 +537,34 @@ acpi_cpu_resume(device_t dev)
 }
 
 /*
- * Find the processor associated with a given ACPI ID.  By default,
- * use the MADT to map ACPI IDs to APIC IDs and use that to locate a
- * processor.  Some systems have inconsistent ASL and MADT however.
- * For these systems the cpu_unordered tunable can be set in which
- * case we assume that Processor objects are listed in the same order
- * in both the MADT and ASL.
+ * Find the processor associated with a given ACPI ID.
  */
 static int
-acpi_pcpu_get_id(device_t dev, uint32_t *acpi_id, uint32_t *cpu_id)
+acpi_pcpu_get_id(device_t dev, uint32_t acpi_id, u_int *cpu_id)
 {
     struct pcpu	*pc;
-    uint32_t	 i, idx;
+    u_int	 i;
 
-    KASSERT(acpi_id != NULL, ("Null acpi_id"));
-    KASSERT(cpu_id != NULL, ("Null cpu_id"));
-    idx = device_get_unit(dev);
+    CPU_FOREACH(i) {
+	pc = pcpu_find(i);
+	if (pc->pc_acpi_id == acpi_id) {
+	    *cpu_id = pc->pc_cpuid;
+	    return (0);
+	}
+    }
 
     /*
      * If pc_acpi_id for CPU 0 is not initialized (e.g. a non-APIC
      * UP box) use the ACPI ID from the first processor we find.
      */
-    if (idx == 0 && mp_ncpus == 1) {
+    if (mp_ncpus == 1) {
 	pc = pcpu_find(0);
 	if (pc->pc_acpi_id == 0xffffffff)
-	    pc->pc_acpi_id = *acpi_id;
+	    pc->pc_acpi_id = acpi_id;
 	*cpu_id = 0;
 	return (0);
     }
 
-    CPU_FOREACH(i) {
-	pc = pcpu_find(i);
-	KASSERT(pc != NULL, ("no pcpu data for %d", i));
-	if (cpu_unordered) {
-	    if (idx-- == 0) {
-		/*
-		 * If pc_acpi_id doesn't match the ACPI ID from the
-		 * ASL, prefer the MADT-derived value.
-		 */
-		if (pc->pc_acpi_id != *acpi_id)
-		    *acpi_id = pc->pc_acpi_id;
-		*cpu_id = pc->pc_cpuid;
-		return (0);
-	    }
-	} else {
-	    if (pc->pc_acpi_id == *acpi_id) {
-		if (bootverbose)
-		    device_printf(dev,
-			"Processor %s (ACPI ID %u) -> APIC ID %d\n",
-			acpi_name(acpi_get_handle(dev)), *acpi_id,
-			pc->pc_cpuid);
-		*cpu_id = pc->pc_cpuid;
-		return (0);
-	    }
-	}
-    }
-
-    if (bootverbose)
-	printf("ACPI: Processor %s (ACPI ID %u) ignored\n",
-	    acpi_name(acpi_get_handle(dev)), *acpi_id);
-
     return (ESRCH);
 }