dm: Add Hardware Spinlock class

This is uclass for Hardware Spinlocks.
It implements two mandatory operations: lock and unlock
and one optional relax operation.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Patrice Chotard <patrice.chotard@st.com>

1 files changed, 56 insertions, 0 deletions

diff --git a/drivers/hwspinlock/sandbox_hwspinlock.c b/drivers/hwspinlock/sandbox_hwspinlock.c
new file mode 100644
index 0000000000..be920f5f99
--- /dev/null
+++ b/drivers/hwspinlock/sandbox_hwspinlock.c
@@ -0,0 +1,56 @@
+// SPDX-License-Identifier: GPL-2.0+ OR BSD-3-Clause
+/*
+ * Copyright (C) 2018, STMicroelectronics - All Rights Reserved
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <hwspinlock.h>
+#include <asm/state.h>
+
+static int sandbox_lock(struct udevice *dev, int index)
+{
+	struct sandbox_state *state = state_get_current();
+
+	if (index != 0)
+		return -1;
+
+	if (state->hwspinlock)
+		return -1;
+
+	state->hwspinlock = true;
+
+	return 0;
+}
+
+static int sandbox_unlock(struct udevice *dev, int index)
+{
+	struct sandbox_state *state = state_get_current();
+
+	if (index != 0)
+		return -1;
+
+	if (!state->hwspinlock)
+		return -1;
+
+	state->hwspinlock = false;
+
+	return 0;
+}
+
+static const struct hwspinlock_ops sandbox_hwspinlock_ops = {
+	.lock = sandbox_lock,
+	.unlock = sandbox_unlock,
+};
+
+static const struct udevice_id sandbox_hwspinlock_ids[] = {
+	{ .compatible = "sandbox,hwspinlock" },
+	{}
+};
+
+U_BOOT_DRIVER(hwspinlock_sandbox) = {
+	.name = "hwspinlock_sandbox",
+	.id = UCLASS_HWSPINLOCK,
+	.of_match = sandbox_hwspinlock_ids,
+	.ops = &sandbox_hwspinlock_ops,
+};