From 5025fc65cd2448de8a5b7295c9936b473a7b0194 Mon Sep 17 00:00:00 2001
From: Matthew Dillon <dillon@apollo.backplane.com>
Date: Mon, 15 Jan 2018 16:37:35 -0800
Subject: [PATCH] kernel - Add a global priority hack for ACPI

* Allows ACPI to fully probe and attach all acpi devices before
  attaching any non-ACPI devices.

* May improve device attach stability.

* Currently only implemented at the top-level of the acpi
  device tree.
---
 sys/dev/acpica/acpi.c            |  10 ++-
 sys/dev/acpica/acpi_acad.c       |   1 +
 sys/dev/acpica/acpi_button.c     |   1 +
 sys/dev/acpica/acpi_cmbat.c      |   1 +
 sys/dev/acpica/acpi_cpu.c        |   3 +-
 sys/dev/acpica/acpi_cpu_cstate.c |   1 +
 sys/dev/acpica/acpi_cpu_pstate.c |   3 +-
 sys/dev/acpica/acpi_ec.c         |   1 +
 sys/dev/acpica/acpi_hpet.c       |   1 +
 sys/dev/acpica/acpi_isab.c       |   1 +
 sys/dev/acpica/acpi_lid.c        |   1 +
 sys/dev/acpica/acpi_pci_link.c   |   1 +
 sys/dev/acpica/acpi_resource.c   |   1 +
 sys/dev/acpica/acpi_smbat.c      |   1 +
 sys/dev/acpica/acpi_thermal.c    |   1 +
 sys/dev/acpica/acpi_timer.c      |   1 +
 sys/kern/subr_bus.c              | 170 ++++++++++++++++++++++++++++++++++++++-
 sys/sys/bus.h                    |   3 +
 sys/sys/kobj.h                   |  11 ++-
 19 files changed, 205 insertions(+), 8 deletions(-)

diff --git a/sys/dev/acpica/acpi.c b/sys/dev/acpica/acpi.c
index ff42107fe7..123f259758 100644
--- a/sys/dev/acpica/acpi.c
+++ b/sys/dev/acpica/acpi.c
@@ -214,6 +214,7 @@ static driver_t acpi_driver = {
     "acpi",
     acpi_methods,
     sizeof(struct acpi_softc),
+    .gpri = KOBJ_GPRI_ACPI
 };
 
 static devclass_t acpi_devclass;
@@ -1666,13 +1667,18 @@ acpi_probe_children(device_t bus)
 
     /* Probe/attach all children, created staticly and from the namespace. */
     ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "first bus_generic_attach\n"));
-    bus_generic_attach(bus);
+    bus_generic_attach_gpri(bus, KOBJ_GPRI_ACPI);
+    ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "second bus_generic_attach\n"));
+    bus_generic_attach_gpri(bus, KOBJ_GPRI_ACPI);
 
     /*
      * Some of these children may have attached others as part of their attach
      * process (eg. the root PCI bus driver), so rescan.
      */
-    ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "second bus_generic_attach\n"));
+    ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "third bus_generic_attach\n"));
+    bus_generic_attach(bus);
+
+    ACPI_DEBUG_PRINT((ACPI_DB_OBJECTS, "fourth bus_generic_attach\n"));
     bus_generic_attach(bus);
 
     /* Attach wake sysctls. */
diff --git a/sys/dev/acpica/acpi_acad.c b/sys/dev/acpica/acpi_acad.c
index 1bfb3636b5..c59a93bb8e 100644
--- a/sys/dev/acpica/acpi_acad.c
+++ b/sys/dev/acpica/acpi_acad.c
@@ -85,6 +85,7 @@ static driver_t acpi_acad_driver = {
     "acpi_acad",
     acpi_acad_methods,
     sizeof(struct acpi_acad_softc),
+    .gpri = KOBJ_GPRI_ACPI
 };
 
 static devclass_t acpi_acad_devclass;
diff --git a/sys/dev/acpica/acpi_button.c b/sys/dev/acpica/acpi_button.c
index 69bf6c3cab..3f46a9b5dd 100644
--- a/sys/dev/acpica/acpi_button.c
+++ b/sys/dev/acpica/acpi_button.c
@@ -86,6 +86,7 @@ static driver_t acpi_button_driver = {
     "acpi_button",
     acpi_button_methods,
     sizeof(struct acpi_button_softc),
+    .gpri = KOBJ_GPRI_ACPI
 };
 
 static devclass_t acpi_button_devclass;
diff --git a/sys/dev/acpica/acpi_cmbat.c b/sys/dev/acpica/acpi_cmbat.c
index d7a6dfc670..1f636430be 100644
--- a/sys/dev/acpica/acpi_cmbat.c
+++ b/sys/dev/acpica/acpi_cmbat.c
@@ -99,6 +99,7 @@ static driver_t acpi_cmbat_driver = {
     "battery",
     acpi_cmbat_methods,
     sizeof(struct acpi_cmbat_softc),
+    .gpri = KOBJ_GPRI_ACPI
 };
 
 static devclass_t acpi_cmbat_devclass;
diff --git a/sys/dev/acpica/acpi_cpu.c b/sys/dev/acpica/acpi_cpu.c
index c81e0bc978..eaa5a4a8b9 100644
--- a/sys/dev/acpica/acpi_cpu.c
+++ b/sys/dev/acpica/acpi_cpu.c
@@ -94,7 +94,8 @@ static device_method_t acpi_cpu_methods[] = {
 static driver_t acpi_cpu_driver = {
     "cpu",
     acpi_cpu_methods,
-    sizeof(struct acpi_cpu_softc)
+    sizeof(struct acpi_cpu_softc),
+    .gpri = KOBJ_GPRI_ACPI
 };
 
 static devclass_t acpi_cpu_devclass;
diff --git a/sys/dev/acpica/acpi_cpu_cstate.c b/sys/dev/acpica/acpi_cpu_cstate.c
index c7fedbd4f3..d643b2eb31 100644
--- a/sys/dev/acpica/acpi_cpu_cstate.c
+++ b/sys/dev/acpica/acpi_cpu_cstate.c
@@ -198,6 +198,7 @@ static driver_t acpi_cst_driver = {
     "cpu_cst",
     acpi_cst_methods,
     sizeof(struct acpi_cst_softc),
+    .gpri = KOBJ_GPRI_ACPI
 };
 
 static devclass_t acpi_cst_devclass;
diff --git a/sys/dev/acpica/acpi_cpu_pstate.c b/sys/dev/acpica/acpi_cpu_pstate.c
index b72a5b02cb..4c391f378c 100644
--- a/sys/dev/acpica/acpi_cpu_pstate.c
+++ b/sys/dev/acpica/acpi_cpu_pstate.c
@@ -224,7 +224,8 @@ static device_method_t acpi_pst_methods[] = {
 static driver_t acpi_pst_driver = {
 	"cpu_pst",
 	acpi_pst_methods,
-	sizeof(struct acpi_pst_softc)
+	sizeof(struct acpi_pst_softc),
+	.gpri = KOBJ_GPRI_ACPI
 };
 
 static devclass_t acpi_pst_devclass;
diff --git a/sys/dev/acpica/acpi_ec.c b/sys/dev/acpica/acpi_ec.c
index d386eb82d9..d586376507 100644
--- a/sys/dev/acpica/acpi_ec.c
+++ b/sys/dev/acpica/acpi_ec.c
@@ -291,6 +291,7 @@ static driver_t acpi_ec_driver = {
     "acpi_ec",
     acpi_ec_methods,
     sizeof(struct acpi_ec_softc),
+    .gpri = KOBJ_GPRI_ACPI
 };
 
 static devclass_t acpi_ec_devclass;
diff --git a/sys/dev/acpica/acpi_hpet.c b/sys/dev/acpica/acpi_hpet.c
index 613dbfe294..3a9641f740 100644
--- a/sys/dev/acpica/acpi_hpet.c
+++ b/sys/dev/acpica/acpi_hpet.c
@@ -98,6 +98,7 @@ static driver_t acpi_hpet_driver = {
 	"acpi_hpet",
 	acpi_hpet_methods,
 	sizeof(struct acpi_hpet_softc),
+	.gpri = KOBJ_GPRI_ACPI
 };
 
 static devclass_t acpi_hpet_devclass;
diff --git a/sys/dev/acpica/acpi_isab.c b/sys/dev/acpica/acpi_isab.c
index 748e1a7c54..b6d56b9de3 100644
--- a/sys/dev/acpica/acpi_isab.c
+++ b/sys/dev/acpica/acpi_isab.c
@@ -83,6 +83,7 @@ static driver_t acpi_isab_driver = {
 	"isab",
 	acpi_isab_methods,
 	sizeof(struct acpi_isab_softc),
+	.gpri = KOBJ_GPRI_ACPI
 };
 
 DRIVER_MODULE(acpi_isab, acpi, acpi_isab_driver, isab_devclass, NULL, NULL);
diff --git a/sys/dev/acpica/acpi_lid.c b/sys/dev/acpica/acpi_lid.c
index fb5f2aeb20..1125ba2d82 100644
--- a/sys/dev/acpica/acpi_lid.c
+++ b/sys/dev/acpica/acpi_lid.c
@@ -77,6 +77,7 @@ static driver_t acpi_lid_driver = {
     "acpi_lid",
     acpi_lid_methods,
     sizeof(struct acpi_lid_softc),
+    .gpri = KOBJ_GPRI_ACPI
 };
 
 static devclass_t acpi_lid_devclass;
diff --git a/sys/dev/acpica/acpi_pci_link.c b/sys/dev/acpica/acpi_pci_link.c
index 80ddceb0ae..ad637fdfa5 100644
--- a/sys/dev/acpica/acpi_pci_link.c
+++ b/sys/dev/acpica/acpi_pci_link.c
@@ -1113,6 +1113,7 @@ static driver_t acpi_pci_link_driver = {
 	"pci_link",
 	acpi_pci_link_methods,
 	sizeof(struct acpi_pci_link_softc),
+	.gpri = KOBJ_GPRI_ACPI
 };
 
 static devclass_t pci_link_devclass;
diff --git a/sys/dev/acpica/acpi_resource.c b/sys/dev/acpica/acpi_resource.c
index c5cf8add9f..75eed314b6 100644
--- a/sys/dev/acpica/acpi_resource.c
+++ b/sys/dev/acpica/acpi_resource.c
@@ -661,6 +661,7 @@ static driver_t acpi_sysres_driver = {
     "acpi_sysresource",
     acpi_sysres_methods,
     0,
+    .gpri = KOBJ_GPRI_ACPI
 };
 
 static devclass_t acpi_sysres_devclass;
diff --git a/sys/dev/acpica/acpi_smbat.c b/sys/dev/acpica/acpi_smbat.c
index 545e218e9f..37672d205d 100644
--- a/sys/dev/acpica/acpi_smbat.c
+++ b/sys/dev/acpica/acpi_smbat.c
@@ -94,6 +94,7 @@ static driver_t	acpi_smbat_driver = {
 	"battery",
 	acpi_smbat_methods,
 	sizeof(struct acpi_smbat_softc),
+	.gpri = KOBJ_GPRI_ACPI
 };
 
 static devclass_t acpi_smbat_devclass;
diff --git a/sys/dev/acpica/acpi_thermal.c b/sys/dev/acpica/acpi_thermal.c
index 81accd4d16..12a91aa436 100644
--- a/sys/dev/acpica/acpi_thermal.c
+++ b/sys/dev/acpica/acpi_thermal.c
@@ -167,6 +167,7 @@ static driver_t acpi_tz_driver = {
     "acpi_tz",
     acpi_tz_methods,
     sizeof(struct acpi_tz_softc),
+    .gpri = KOBJ_GPRI_ACPI
 };
 
 static char *acpi_tz_tmp_name = "_TMP";
diff --git a/sys/dev/acpica/acpi_timer.c b/sys/dev/acpica/acpi_timer.c
index 83da56f97f..45df3f0126 100644
--- a/sys/dev/acpica/acpi_timer.c
+++ b/sys/dev/acpica/acpi_timer.c
@@ -93,6 +93,7 @@ static driver_t acpi_timer_driver = {
     "acpi_timer",
     acpi_timer_methods,
     0,
+    .gpri = KOBJ_GPRI_ACPI
 };
 
 static devclass_t acpi_timer_devclass;
diff --git a/sys/kern/subr_bus.c b/sys/kern/subr_bus.c
index 0e2bb99a59..b41ec9f918 100644
--- a/sys/kern/subr_bus.c
+++ b/sys/kern/subr_bus.c
@@ -1233,9 +1233,10 @@ device_add_child_ordered(device_t dev, int order, const char *name, int unit)
 		return child;
 	child->order = order;
 
-	TAILQ_FOREACH(place, &dev->children, link)
+	TAILQ_FOREACH(place, &dev->children, link) {
 		if (place->order > order)
 			break;
+	}
 
 	if (place) {
 		/*
@@ -1392,7 +1393,7 @@ device_probe_child(device_t dev, device_t child)
 		return(0);
 
 	for (; dc; dc = dc->parent) {
-    		for (dl = first_matching_driver(dc, child); dl;
+		for (dl = first_matching_driver(dc, child); dl;
 		     dl = next_matching_driver(dc, child, dl)) {
 			PDEBUG(("Trying %s", DRIVERNAME(dl->driver)));
 			device_set_driver(child, dl->driver);
@@ -1431,13 +1432,108 @@ device_probe_child(device_t dev, device_t child)
 				pri = result;
 				continue;
 			}
+		}
+		/*
+	         * If we have unambiguous match in this devclass,
+	         * don't look in the parent.
+	         */
+	        if (best && pri == 0)
+			break;
+	}
+
+	/*
+	 * If we found a driver, change state and initialise the devclass.
+	 */
+	if (best) {
+		if (!child->devclass)
+			device_set_devclass(child, best->driver->name);
+		device_set_driver(child, best->driver);
+		if (pri < 0) {
+			/*
+			 * A bit bogus. Call the probe method again to make
+			 * sure that we have the right description.
+			 */
+			DEVICE_PROBE(child);
+		}
+
+		bus_data_generation_update();
+		child->state = DS_ALIVE;
+		return(0);
+	}
+
+	return(ENXIO);
+}
+
+int
+device_probe_child_gpri(device_t dev, device_t child, u_int gpri)
+{
+	devclass_t dc;
+	driverlink_t best = NULL;
+	driverlink_t dl;
+	int result, pri = 0;
+	int hasclass = (child->devclass != NULL);
+
+	dc = dev->devclass;
+	if (!dc)
+		panic("device_probe_child: parent device has no devclass");
+
+	if (child->state == DS_ALIVE)
+		return(0);
+
+	for (; dc; dc = dc->parent) {
+		for (dl = first_matching_driver(dc, child); dl;
+			dl = next_matching_driver(dc, child, dl)) {
+			/*
+			 * GPRI handling, only probe drivers with the
+			 * specific GPRI.
+			 */
+			if (dl->driver->gpri != gpri)
+				continue;
+
+			PDEBUG(("Trying %s", DRIVERNAME(dl->driver)));
+			device_set_driver(child, dl->driver);
+			if (!hasclass)
+				device_set_devclass(child, dl->driver->name);
+			result = DEVICE_PROBE(child);
+			if (!hasclass)
+				device_set_devclass(child, 0);
+
+			/*
+			 * If the driver returns SUCCESS, there can be
+			 * no higher match for this device.
+			 */
+			if (result == 0) {
+				best = dl;
+				pri = 0;
+				break;
+			}
+
+			/*
+			 * The driver returned an error so it
+			 * certainly doesn't match.
+			 */
+			if (result > 0) {
+				device_set_driver(child, NULL);
+				continue;
+			}
+
+			/*
+			 * A priority lower than SUCCESS, remember the
+			 * best matching driver. Initialise the value
+			 * of pri for the first match.
+			 */
+			if (best == NULL || result > pri) {
+				best = dl;
+				pri = result;
+				continue;
+			}
 	        }
 		/*
 	         * If we have unambiguous match in this devclass,
 	         * don't look in the parent.
 	         */
 	        if (best && pri == 0)
-	    	        break;
+			break;
 	}
 
 	/*
@@ -1851,6 +1947,62 @@ device_probe_and_attach(device_t dev)
 	return(error);
 }
 
+int
+device_probe_and_attach_gpri(device_t dev, u_int gpri)
+{
+	device_t bus = dev->parent;
+	int error = 0;
+
+	if (dev->state >= DS_ALIVE)
+		return(0);
+
+	if ((dev->flags & DF_ENABLED) == 0) {
+		if (bootverbose) {
+			device_print_prettyname(dev);
+			kprintf("not probed (disabled)\n");
+		}
+		return(0);
+	}
+
+	error = device_probe_child_gpri(bus, dev, gpri);
+	if (error) {
+#if 0
+		if (!(dev->flags & DF_DONENOMATCH)) {
+			BUS_PROBE_NOMATCH(bus, dev);
+			devnomatch(dev);
+			dev->flags |= DF_DONENOMATCH;
+		}
+#endif
+		return(error);
+	}
+
+	/*
+	 * Output the exact device chain prior to the attach in case the
+	 * system locks up during attach, and generate the full info after
+	 * the attach so correct irq and other information is displayed.
+	 */
+	if (bootverbose && !device_is_quiet(dev)) {
+		device_t tmp;
+
+		kprintf("%s", device_get_nameunit(dev));
+		for (tmp = dev->parent; tmp; tmp = tmp->parent)
+			kprintf(".%s", device_get_nameunit(tmp));
+		kprintf("\n");
+	}
+	if (!device_is_quiet(dev))
+		device_print_child(bus, dev);
+	if ((dev->flags & DF_ASYNCPROBE) && do_async_attach) {
+		kprintf("%s: probing asynchronously\n",
+			device_get_nameunit(dev));
+		dev->state = DS_INPROGRESS;
+		device_attach_async(dev);
+		error = 0;
+	} else {
+		error = device_doattach(dev);
+	}
+	return(error);
+}
+
 /*
  * Device is known to be alive, do the attach asynchronously.
  * However, serialize the attaches with the mp lock.
@@ -2633,6 +2785,18 @@ bus_generic_attach(device_t dev)
 }
 
 int
+bus_generic_attach_gpri(device_t dev, u_int gpri)
+{
+	device_t child;
+
+	TAILQ_FOREACH(child, &dev->children, link) {
+		device_probe_and_attach_gpri(child, gpri);
+	}
+
+	return(0);
+}
+
+int
 bus_generic_detach(device_t dev)
 {
 	device_t child;
diff --git a/sys/sys/bus.h b/sys/sys/bus.h
index 7f09ebb78d..e614b2314c 100644
--- a/sys/sys/bus.h
+++ b/sys/sys/bus.h
@@ -245,6 +245,7 @@ struct resource_list *
 int     bus_generic_config_intr(device_t, device_t, int, enum intr_trigger,
 					enum intr_polarity);
 int	bus_generic_attach(device_t dev);
+int	bus_generic_attach_gpri(device_t dev, u_int gpri);
 int	bus_generic_child_present(device_t dev, device_t child);
 int	bus_generic_deactivate_resource(device_t dev, device_t child, int type,
 					int rid, struct resource *r);
@@ -383,7 +384,9 @@ int	device_is_quiet(device_t dev);
 int	device_print_prettyname(device_t dev);
 int	device_printf(device_t dev, const char *, ...) __printflike(2, 3);
 int	device_probe_and_attach(device_t dev);
+int	device_probe_and_attach_gpri(device_t dev, u_int gpri);
 int	device_probe_child(device_t dev, device_t child);
+int	device_probe_child_gpri(device_t dev, device_t child, u_int gpri);
 void	device_quiet(device_t dev);
 void	device_set_desc(device_t dev, const char* desc);
 void	device_set_desc_copy(device_t dev, const char* desc);
diff --git a/sys/sys/kobj.h b/sys/sys/kobj.h
index d002baed02..e023fc9358 100644
--- a/sys/sys/kobj.h
+++ b/sys/sys/kobj.h
@@ -65,7 +65,8 @@ struct kobj_method {
 	size_t		size;		/* object size */		\
 	kobj_class_t	*baseclasses;	/* base classes */		\
 	u_int		refs;		/* reference count */		\
-	kobj_ops_t	ops		/* compiled method table */
+	kobj_ops_t	ops;		/* compiled method table */	\
+	u_int		gpri		/* global probe/attach pri */
 
 struct kobj_class {
 	KOBJ_CLASS_FIELDS;
@@ -82,6 +83,14 @@ struct kobj {
 };
 
 /*
+ * gpri values (higher values probe/attach first, allows us to
+ * default the field to 0).
+ */
+#define KOBJ_GPRI_ACPI		0x00FFU
+#define KOBJ_GPRI_LAST		0x0000U
+#define KOBJ_GPRI_DEFAULT	KOBJ_GPRI_LAST
+
+/*
  * The ops table is used as a cache of results from kobj_lookup_method().
  */
 
-- 
2.11.4.GIT