1 files changed, 105 insertions, 0 deletions
diff --git a/arch/arm/mach-mvebu/system-controller.c b/arch/arm/mach-mvebu/system-controller.c
new file mode 100644
index 00000000000..ea858b269e8
--- /dev/null
+++ b/arch/arm/mach-mvebu/system-controller.c
@@ -0,0 +1,105 @@
+// SPDX-License-Identifier: GPL-2.0+
+// (C) 2021 Pali Rohár <pali@kernel.org>
+
+#include <common.h>
+#include <dm.h>
+#include <reset-uclass.h>
+#include <asm/io.h>
+
+#define MVEBU_SOC_CONTROL_1_REG 0x4
+
+#define MVEBU_PCIE_ID 0
+
+struct mvebu_reset_data {
+	void *base;
+};
+
+static int mvebu_reset_of_xlate(struct reset_ctl *rst,
+				struct ofnode_phandle_args *args)
+{
+	if (args->args_count < 2)
+		return -EINVAL;
+
+	rst->id = args->args[0];
+	rst->data = args->args[1];
+
+	/* Currently only PCIe is implemented */
+	if (rst->id != MVEBU_PCIE_ID)
+		return -EINVAL;
+
+	/* Four PCIe enable bits are shared across more PCIe links */
+	if (!(rst->data >= 0 && rst->data <= 3))
+		return -EINVAL;
+
+	return 0;
+}
+
+static int mvebu_reset_request(struct reset_ctl *rst)
+{
+	return 0;
+}
+
+static int mvebu_reset_free(struct reset_ctl *rst)
+{
+	return 0;
+}
+
+static int mvebu_reset_assert(struct reset_ctl *rst)
+{
+	struct mvebu_reset_data *data = dev_get_priv(rst->dev);
+
+	clrbits_32(data->base + MVEBU_SOC_CONTROL_1_REG, BIT(rst->data));
+	return 0;
+}
+
+static int mvebu_reset_deassert(struct reset_ctl *rst)
+{
+	struct mvebu_reset_data *data = dev_get_priv(rst->dev);
+
+	setbits_32(data->base + MVEBU_SOC_CONTROL_1_REG, BIT(rst->data));
+	return 0;
+}
+
+static int mvebu_reset_status(struct reset_ctl *rst)
+{
+	struct mvebu_reset_data *data = dev_get_priv(rst->dev);
+
+	return !(readl(data->base + MVEBU_SOC_CONTROL_1_REG) & BIT(rst->data));
+}
+
+static int mvebu_reset_of_to_plat(struct udevice *dev)
+{
+	struct mvebu_reset_data *data = dev_get_priv(dev);
+
+	data->base = (void *)dev_read_addr(dev);
+	if ((fdt_addr_t)data->base == FDT_ADDR_T_NONE)
+		return -EINVAL;
+
+	return 0;
+}
+
+static const struct udevice_id mvebu_reset_of_match[] = {
+	{ .compatible = "marvell,armada-370-xp-system-controller" },
+	{ .compatible = "marvell,armada-375-system-controller" },
+	{ .compatible = "marvell,armada-380-system-controller" },
+	{ .compatible = "marvell,armada-390-system-controller" },
+	{ },
+};
+
+static struct reset_ops mvebu_reset_ops = {
+	.of_xlate = mvebu_reset_of_xlate,
+	.request = mvebu_reset_request,
+	.rfree = mvebu_reset_free,
+	.rst_assert = mvebu_reset_assert,
+	.rst_deassert = mvebu_reset_deassert,
+	.rst_status = mvebu_reset_status,
+};
+
+U_BOOT_DRIVER(mvebu_reset) = {
+	.name = "mvebu-reset",
+	.id = UCLASS_RESET,
+	.of_match = mvebu_reset_of_match,
+	.of_to_plat = mvebu_reset_of_to_plat,
+	.priv_auto = sizeof(struct mvebu_reset_data),
+	.ops = &mvebu_reset_ops,
+};