Add a "regmap" interface that allows devices to provide access to their

registers to devices that live elsewhere in the device tree.

ok patrick@

2 files changed, 110 insertions, 0 deletions

diff --git a/sys/dev/ofw/ofw_misc.c b/sys/dev/ofw/ofw_misc.c
new file mode 100644
index 00000000000..e3de2a1719d
--- /dev/null
+++ b/sys/dev/ofw/ofw_misc.c
@@ -0,0 +1,81 @@
+/*	$OpenBSD: ofw_misc.c,v 1.1 2017/03/09 20:01:10 kettenis Exp $	*/
+/*
+ * Copyright (c) 2017 Mark Kettenis
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+#include <sys/systm.h>
+#include <sys/malloc.h>
+
+#include <machine/bus.h>
+
+#include <dev/ofw/openfirm.h>
+#include <dev/ofw/ofw_pinctrl.h>
+
+struct regmap {
+	uint32_t		rm_phandle;
+	bus_space_tag_t		rm_tag;
+	bus_space_handle_t	rm_handle;
+	bus_size_t		rm_size;
+	
+	LIST_ENTRY(regmap)	rm_list;
+};
+
+LIST_HEAD(, regmap) regmaps = LIST_HEAD_INITIALIZER(regmap);
+
+void
+regmap_register(int node, bus_space_tag_t tag, bus_space_handle_t handle,
+    bus_size_t size)
+{
+	struct regmap *rm;
+	uint32_t phandle;
+
+	phandle = OF_getpropint(node, "phandle", 0);
+	if (phandle) {
+		rm = malloc(sizeof(struct regmap), M_DEVBUF, M_WAITOK);
+		rm->rm_phandle = phandle;
+		rm->rm_tag = tag;
+		rm->rm_handle = handle;
+		rm->rm_size = size;
+		LIST_INSERT_HEAD(&regmaps, rm, rm_list);
+	}
+}
+
+struct regmap *
+regmap_byphandle(uint32_t phandle)
+{
+	struct regmap *rm;
+
+	LIST_FOREACH(rm, &regmaps, rm_list) {
+		if (rm->rm_phandle == phandle)
+			return rm;
+	}
+
+	return NULL;
+}
+
+void
+regmap_write_4(struct regmap *rm, bus_size_t offset, uint32_t value)
+{
+	KASSERT(offset <= rm->rm_size - sizeof(uint32_t));
+	bus_space_write_4(rm->rm_tag, rm->rm_handle, offset, value);
+}
+
+uint32_t
+regmap_read_4(struct regmap *rm, bus_size_t offset)
+{
+	KASSERT(offset <= rm->rm_size - sizeof(uint32_t));
+	return bus_space_read_4(rm->rm_tag, rm->rm_handle, offset);
+}
diff --git a/sys/dev/ofw/ofw_misc.h b/sys/dev/ofw/ofw_misc.h
new file mode 100644
index 00000000000..37bd01105ec
--- /dev/null
+++ b/sys/dev/ofw/ofw_misc.h
@@ -0,0 +1,29 @@
+/*	$OpenBSD: ofw_misc.h,v 1.1 2017/03/09 20:01:10 kettenis Exp $	*/
+/*
+ * Copyright (c) 2017 Mark Kettenis
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifndef _DEV_OFW_MISC_H_
+#define _DEV_OFW_MISC_H_
+
+void	regmap_register(int, bus_space_tag_t, bus_space_handle_t, bus_size_t);
+
+struct regmap;
+struct regmap *regmap_byphandle(uint32_t);
+
+uint32_t regmap_read_4(struct regmap *, bus_size_t);
+void	regmap_write_4(struct regmap *, bus_size_t, uint32_t);
+
+#endif /* _DEV_OFW_MISC_H_ */