Adda function to iterate over the cpu nodes in the OFW or FDT data. This

will be used with arm64 to find which cpus to enable, and could also be
used with 32-bit arm and mips for the same purpose.

Differential Revision:	https://reviews.freebsd.org/D1825
Sponsored by:	The FreeBSD Foundation

2 files changed, 86 insertions, 0 deletions

diff --git a/sys/dev/ofw/ofw_cpu.c b/sys/dev/ofw/ofw_cpu.c
index 250419f..59e49ee 100644
--- a/sys/dev/ofw/ofw_cpu.c
+++ b/sys/dev/ofw/ofw_cpu.c
@@ -43,6 +43,7 @@ __FBSDID("$FreeBSD$");
 #include <dev/ofw/openfirm.h>
 #include <dev/ofw/ofw_bus.h>
 #include <dev/ofw/ofw_bus_subr.h>
+#include <dev/ofw/ofw_cpu.h>
 
 static int	ofw_cpulist_probe(device_t);
 static int	ofw_cpulist_attach(device_t);
@@ -274,3 +275,50 @@ ofw_cpu_read_ivar(device_t dev, device_t child, int index, uintptr_t *result)
 	return (ENOENT);
 }
 
+int
+ofw_cpu_early_foreach(ofw_cpu_foreach_cb callback, boolean_t only_runnable)
+{
+	phandle_t node, child;
+	pcell_t addr_cells, reg[2];
+	char status[16];
+	u_int id;
+	int count, rv;
+
+	count = 0;
+	id = 0;
+
+	node = OF_finddevice("/cpus");
+	if (node == -1)
+		return (-1);
+
+	/* Find the number of cells in the cpu register */
+	if (OF_getencprop(node, "#address-cells", &addr_cells,
+	    sizeof(addr_cells)) < 0)
+		return (-1);
+
+	for (child = OF_child(node); child != 0; child = OF_peer(child), id++) {
+		/*
+		 * If we are filtering by runnable then limit to only
+		 * those that have been enabled.
+		 */
+		if (only_runnable) {
+			status[0] = '\0';
+			OF_getprop(child, "status", status, sizeof(status));
+			if (status[0] != '\0' && strcmp(status, "okay") != 0)
+				continue;
+		}
+
+		/*
+		 * Check we have a register to identify the cpu
+		 */
+		rv = OF_getencprop(child, "reg", reg,
+		    addr_cells * sizeof(cell_t));
+		if (rv != addr_cells * sizeof(cell_t))
+			continue;
+
+		if (callback == NULL || callback(id, child, addr_cells, reg))
+			count++;
+	}
+
+	return (only_runnable ? count : id);
+}
diff --git a/sys/dev/ofw/ofw_cpu.h b/sys/dev/ofw/ofw_cpu.h
new file mode 100644
index 0000000..9ac9171
--- /dev/null
+++ b/sys/dev/ofw/ofw_cpu.h
@@ -0,0 +1,38 @@
+/*-
+ * Copyright (c) 2015 The FreeBSD Foundation
+ * All rights reserved.
+ *
+ * This software was developed by Andrew Turner under
+ * sponsorship from the FreeBSD Foundation.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _DEV_OFW_OFW_CPU_H_
+#define _DEV_OFW_OFW_CPU_H_
+
+typedef boolean_t (*ofw_cpu_foreach_cb)(u_int, phandle_t, u_int, pcell_t *);
+int ofw_cpu_early_foreach(ofw_cpu_foreach_cb, boolean_t);
+
+#endif /* _DEV_OFW_OFW_CPU_H_ */