Implement a power domain framework to turn on/off so-called power

domains.  This mechanism is used by the newer i.MX8M SoCs so that
drivers can call into ATF to supply power to e.g. a USB port.

ok kettenis@

2 files changed, 142 insertions, 0 deletions

diff --git a/sys/dev/ofw/ofw_power.c b/sys/dev/ofw/ofw_power.c
new file mode 100644
index 00000000000..96aa74dd929
--- /dev/null
+++ b/sys/dev/ofw/ofw_power.c
@@ -0,0 +1,106 @@
+/*	$OpenBSD: ofw_power.c,v 1.1 2018/05/02 15:16:31 patrick Exp $	*/
+/*
+ * Copyright (c) 2016 Mark Kettenis
+ * Copyright (c) 2018 Patrick Wildt <patrick@blueri.se>
+ *
+ * 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 <dev/ofw/openfirm.h>
+#include <dev/ofw/ofw_power.h>
+
+LIST_HEAD(, power_domain_device) power_domain_devices =
+	LIST_HEAD_INITIALIZER(power_domain_devices);
+
+void
+power_domain_register(struct power_domain_device *pd)
+{
+	pd->pd_cells = OF_getpropint(pd->pd_node, "#power-domain-cells", 0);
+	pd->pd_phandle = OF_getpropint(pd->pd_node, "phandle", 0);
+	if (pd->pd_phandle == 0)
+		return;
+
+	LIST_INSERT_HEAD(&power_domain_devices, pd, pd_list);
+}
+
+void
+power_domain_enable_cells(uint32_t *cells, int on)
+{
+	struct power_domain_device *pd;
+	uint32_t phandle = cells[0];
+
+	LIST_FOREACH(pd, &power_domain_devices, pd_list) {
+		if (pd->pd_phandle == phandle)
+			break;
+	}
+
+	if (pd && pd->pd_enable)
+		pd->pd_enable(pd->pd_cookie, &cells[1], on);
+}
+
+uint32_t *
+power_domain_next_domain(uint32_t *cells)
+{
+	uint32_t phandle = cells[0];
+	int node, ncells;
+
+	node = OF_getnodebyphandle(phandle);
+	if (node == 0)
+		return NULL;
+
+	ncells = OF_getpropint(node, "#power-domain-cells", 0);
+	return cells + ncells + 1;
+}
+
+void
+power_domain_do_enable_idx(int node, int idx, int on)
+{
+	uint32_t *domains;
+	uint32_t *domain;
+	int len;
+
+	len = OF_getproplen(node, "power-domains");
+	if (len <= 0)
+		return;
+
+	domains = malloc(len, M_TEMP, M_WAITOK);
+	OF_getpropintarray(node, "power-domains", domains, len);
+
+	domain = domains;
+	while (domain && domain < domains + (len / sizeof(uint32_t))) {
+		if (idx <= 0)
+			power_domain_enable_cells(domain, on);
+		if (idx == 0)
+			break;
+		domain = power_domain_next_domain(domain);
+		idx--;
+	}
+
+	free(domains, M_TEMP, len);
+}
+
+void
+power_domain_enable(int node)
+{
+	power_domain_do_enable_idx(node, 0, 1);
+}
+
+void
+power_domain_disable(int node)
+{
+	power_domain_do_enable_idx(node, 0, 0);
+}
diff --git a/sys/dev/ofw/ofw_power.h b/sys/dev/ofw/ofw_power.h
new file mode 100644
index 00000000000..f18871375a0
--- /dev/null
+++ b/sys/dev/ofw/ofw_power.h
@@ -0,0 +1,36 @@
+/*	$OpenBSD: ofw_power.h,v 1.1 2018/05/02 15:16:31 patrick Exp $	*/
+/*
+ * Copyright (c) 2016 Mark Kettenis
+ * Copyright (c) 2018 Patrick Wildt <patrick@blueri.se>
+ *
+ * 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_POWER_H_
+#define _DEV_OFW_POWER_H_
+
+struct power_domain_device {
+	int	pd_node;
+	void	*pd_cookie;
+	void	(*pd_enable)(void *, uint32_t *, int);
+
+	LIST_ENTRY(power_domain_device) pd_list;
+	uint32_t pd_phandle;
+	uint32_t pd_cells;
+};
+
+void	power_domain_register(struct power_domain_device *);
+void	power_domain_enable(int);
+void	power_domain_disable(int);
+
+#endif /* _DEV_OFW_POWER_H_ */