Add the beginnings of an nvmem "framework".

ok patrick@

2 files changed, 46 insertions, 2 deletions

diff --git a/sys/dev/ofw/ofw_misc.c b/sys/dev/ofw/ofw_misc.c
index dd98ee8c4af..7856088933f 100644
--- a/sys/dev/ofw/ofw_misc.c
+++ b/sys/dev/ofw/ofw_misc.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ofw_misc.c,v 1.10 2019/09/30 20:40:54 kettenis Exp $	*/
+/*	$OpenBSD: ofw_misc.c,v 1.11 2020/01/21 00:21:55 kettenis Exp $	*/
 /*
  * Copyright (c) 2017 Mark Kettenis
  *
@@ -337,3 +337,33 @@ pwm_set_state(uint32_t *cells, struct pwm_state *ps)
 
 	return ENXIO;
 }
+
+/*
+ * Non-volatile memory support.
+ */
+
+LIST_HEAD(, nvmem_device) nvmem_devices =
+	LIST_HEAD_INITIALIZER(nvmem_devices);
+
+void
+nvmem_register(struct nvmem_device *nd)
+{
+	nd->nd_phandle = OF_getpropint(nd->nd_node, "phandle", 0);
+	if (nd->nd_phandle == 0)
+		return;
+
+	LIST_INSERT_HEAD(&nvmem_devices, nd, nd_list);
+}
+
+int
+nvmem_read(uint32_t phandle, bus_addr_t addr, void *data, bus_size_t size)
+{
+	struct nvmem_device *nd;
+
+	LIST_FOREACH(nd, &nvmem_devices, nd_list) {
+		if (nd->nd_phandle == phandle)
+			return nd->nd_read(nd->nd_cookie, addr, data, size);
+	}
+
+	return ENXIO;
+}
diff --git a/sys/dev/ofw/ofw_misc.h b/sys/dev/ofw/ofw_misc.h
index 3c3f75307a7..d286ea1fecf 100644
--- a/sys/dev/ofw/ofw_misc.h
+++ b/sys/dev/ofw/ofw_misc.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ofw_misc.h,v 1.7 2019/09/30 20:40:54 kettenis Exp $	*/
+/*	$OpenBSD: ofw_misc.h,v 1.8 2020/01/21 00:21:55 kettenis Exp $	*/
 /*
  * Copyright (c) 2017 Mark Kettenis
  *
@@ -114,4 +114,18 @@ int	pwm_init_state(uint32_t *cells, struct pwm_state *ps);
 int	pwm_get_state(uint32_t *cells, struct pwm_state *ps);
 int	pwm_set_state(uint32_t *cells, struct pwm_state *ps);
 
+/* Non-volatile memory support */
+
+struct nvmem_device {
+	int	nd_node;
+	void	*nd_cookie;
+	int	(*nd_read)(void *, bus_addr_t, void *, bus_size_t);
+
+	LIST_ENTRY(nvmem_device) nd_list;
+	uint32_t nd_phandle;
+};
+
+void	nvmem_register(struct nvmem_device *);
+int	nvmem_read(uint32_t, bus_addr_t, void *, bus_size_t);
+
 #endif /* _DEV_OFW_MISC_H_ */