From: patrick <patrick@openbsd.org>
Date: Wed, 17 May 2023 23:25:45 +0000 (+0000)
Subject: Add a framework for hardware locks.
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=949f008f01ce4510c6cf4a111524f59a568b1d46;p=openbsd

Add a framework for hardware locks.

ok kettenis@ drahn@
---

diff --git a/sys/dev/ofw/ofw_misc.c b/sys/dev/ofw/ofw_misc.c
index 3bcb6f3b013..90f541fd5d7 100644
--- a/sys/dev/ofw/ofw_misc.c
+++ b/sys/dev/ofw/ofw_misc.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ofw_misc.c,v 1.42 2023/04/26 21:37:46 patrick Exp $	*/
+/*	$OpenBSD: ofw_misc.c,v 1.43 2023/05/17 23:25:45 patrick Exp $	*/
 /*
  * Copyright (c) 2017-2021 Mark Kettenis
  *
@@ -1344,3 +1344,108 @@ mbox_recv(struct mbox_channel *mc, void *data, size_t len)
 
 	return ENXIO;
 }
+
+/* hwlock support */
+
+LIST_HEAD(, hwlock_device) hwlock_devices =
+	LIST_HEAD_INITIALIZER(hwlock_devices);
+
+void
+hwlock_register(struct hwlock_device *hd)
+{
+	hd->hd_cells = OF_getpropint(hd->hd_node, "#hwlock-cells", 0);
+	hd->hd_phandle = OF_getpropint(hd->hd_node, "phandle", 0);
+	if (hd->hd_phandle == 0)
+		return;
+
+	LIST_INSERT_HEAD(&hwlock_devices, hd, hd_list);
+}
+
+int
+hwlock_lock_cells(uint32_t *cells, int lock)
+{
+	struct hwlock_device *hd;
+	uint32_t phandle = cells[0];
+
+	LIST_FOREACH(hd, &hwlock_devices, hd_list) {
+		if (hd->hd_phandle == phandle)
+			break;
+	}
+
+	if (hd && hd->hd_lock)
+		return hd->hd_lock(hd->hd_cookie, &cells[1], lock);
+
+	return ENXIO;
+}
+
+uint32_t *
+hwlock_next_hwlock(uint32_t *cells)
+{
+	uint32_t phandle = cells[0];
+	int node, ncells;
+
+	node = OF_getnodebyphandle(phandle);
+	if (node == 0)
+		return NULL;
+
+	ncells = OF_getpropint(node, "#hwlock-cells", 0);
+	return cells + ncells + 1;
+}
+
+int
+hwlock_do_lock_idx(int node, int idx, int lock)
+{
+	uint32_t *hwlocks;
+	uint32_t *hwlock;
+	int rv = -1;
+	int len;
+
+	len = OF_getproplen(node, "hwlocks");
+	if (len <= 0)
+		return -1;
+
+	hwlocks = malloc(len, M_TEMP, M_WAITOK);
+	OF_getpropintarray(node, "hwlocks", hwlocks, len);
+
+	hwlock = hwlocks;
+	while (hwlock && hwlock < hwlocks + (len / sizeof(uint32_t))) {
+		if (idx <= 0)
+			rv = hwlock_lock_cells(hwlock, lock);
+		if (idx == 0)
+			break;
+		hwlock = hwlock_next_hwlock(hwlock);
+		idx--;
+	}
+
+	free(hwlocks, M_TEMP, len);
+	return rv;
+}
+
+int
+hwlock_lock_idx(int node, int idx)
+{
+	return hwlock_do_lock_idx(node, idx, 1);
+}
+
+int
+hwlock_lock_idx_timeout(int node, int idx, int ms)
+{
+	int i, ret = ENXIO;
+
+	for (i = 0; i <= ms; i++) {
+		ret = hwlock_do_lock_idx(node, idx, 1);
+		if (ret == EAGAIN) {
+			delay(1000);
+			continue;
+		}
+		break;
+	}
+
+	return ret;
+}
+
+int
+hwlock_unlock_idx(int node, int idx)
+{
+	return hwlock_do_lock_idx(node, idx, 0);
+}
diff --git a/sys/dev/ofw/ofw_misc.h b/sys/dev/ofw/ofw_misc.h
index 6a21576b477..ae4a81463f8 100644
--- a/sys/dev/ofw/ofw_misc.h
+++ b/sys/dev/ofw/ofw_misc.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ofw_misc.h,v 1.29 2023/04/03 01:40:32 dlg Exp $	*/
+/*	$OpenBSD: ofw_misc.h,v 1.30 2023/05/17 23:25:45 patrick Exp $	*/
 /*
  * Copyright (c) 2017-2021 Mark Kettenis
  *
@@ -313,4 +313,22 @@ struct mbox_channel *mbox_channel_idx(int, int, struct mbox_client *);
 int	mbox_send(struct mbox_channel *, const void *, size_t);
 int	mbox_recv(struct mbox_channel *, void *, size_t);
 
+/* hwlock support */
+
+struct hwlock_device {
+	int	hd_node;
+	void	*hd_cookie;
+	int	(*hd_lock)(void *, uint32_t *, int);
+
+	LIST_ENTRY(hwlock_device) hd_list;
+	uint32_t hd_phandle;
+	uint32_t hd_cells;
+};
+
+void	hwlock_register(struct hwlock_device *);
+
+int	hwlock_lock_idx(int, int);
+int	hwlock_lock_idx_timeout(int, int, int);
+int	hwlock_unlock_idx(int, int);
+
 #endif /* _DEV_OFW_MISC_H_ */