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-rw-r--r--drivers/clk/rockchip/softrst.c110
1 files changed, 110 insertions, 0 deletions
diff --git a/drivers/clk/rockchip/softrst.c b/drivers/clk/rockchip/softrst.c
new file mode 100644
index 000000000..5d0726674
--- /dev/null
+++ b/drivers/clk/rockchip/softrst.c
@@ -0,0 +1,110 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2014 MundoReader S.L.
+ * Author: Heiko Stuebner <heiko@sntech.de>
+ */
+
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/reset-controller.h>
+#include <linux/spinlock.h>
+#include "clk.h"
+
+struct rockchip_softrst {
+ struct reset_controller_dev rcdev;
+ void __iomem *reg_base;
+ int num_regs;
+ int num_per_reg;
+ u8 flags;
+ spinlock_t lock;
+};
+
+static int rockchip_softrst_assert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct rockchip_softrst *softrst = container_of(rcdev,
+ struct rockchip_softrst,
+ rcdev);
+ int bank = id / softrst->num_per_reg;
+ int offset = id % softrst->num_per_reg;
+
+ if (softrst->flags & ROCKCHIP_SOFTRST_HIWORD_MASK) {
+ writel(BIT(offset) | (BIT(offset) << 16),
+ softrst->reg_base + (bank * 4));
+ } else {
+ unsigned long flags;
+ u32 reg;
+
+ spin_lock_irqsave(&softrst->lock, flags);
+
+ reg = readl(softrst->reg_base + (bank * 4));
+ writel(reg | BIT(offset), softrst->reg_base + (bank * 4));
+
+ spin_unlock_irqrestore(&softrst->lock, flags);
+ }
+
+ return 0;
+}
+
+static int rockchip_softrst_deassert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct rockchip_softrst *softrst = container_of(rcdev,
+ struct rockchip_softrst,
+ rcdev);
+ int bank = id / softrst->num_per_reg;
+ int offset = id % softrst->num_per_reg;
+
+ if (softrst->flags & ROCKCHIP_SOFTRST_HIWORD_MASK) {
+ writel((BIT(offset) << 16), softrst->reg_base + (bank * 4));
+ } else {
+ unsigned long flags;
+ u32 reg;
+
+ spin_lock_irqsave(&softrst->lock, flags);
+
+ reg = readl(softrst->reg_base + (bank * 4));
+ writel(reg & ~BIT(offset), softrst->reg_base + (bank * 4));
+
+ spin_unlock_irqrestore(&softrst->lock, flags);
+ }
+
+ return 0;
+}
+
+static const struct reset_control_ops rockchip_softrst_ops = {
+ .assert = rockchip_softrst_assert,
+ .deassert = rockchip_softrst_deassert,
+};
+
+void rockchip_register_softrst(struct device_node *np,
+ unsigned int num_regs,
+ void __iomem *base, u8 flags)
+{
+ struct rockchip_softrst *softrst;
+ int ret;
+
+ softrst = kzalloc(sizeof(*softrst), GFP_KERNEL);
+ if (!softrst)
+ return;
+
+ spin_lock_init(&softrst->lock);
+
+ softrst->reg_base = base;
+ softrst->flags = flags;
+ softrst->num_regs = num_regs;
+ softrst->num_per_reg = (flags & ROCKCHIP_SOFTRST_HIWORD_MASK) ? 16
+ : 32;
+
+ softrst->rcdev.owner = THIS_MODULE;
+ softrst->rcdev.nr_resets = num_regs * softrst->num_per_reg;
+ softrst->rcdev.ops = &rockchip_softrst_ops;
+ softrst->rcdev.of_node = np;
+ ret = reset_controller_register(&softrst->rcdev);
+ if (ret) {
+ pr_err("%s: could not register reset controller, %d\n",
+ __func__, ret);
+ kfree(softrst);
+ }
+};
+EXPORT_SYMBOL_GPL(rockchip_register_softrst);