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path: root/drivers/clk/socfpga/clk-gate-a10.c
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Diffstat (limited to 'drivers/clk/socfpga/clk-gate-a10.c')
-rw-r--r--drivers/clk/socfpga/clk-gate-a10.c121
1 files changed, 121 insertions, 0 deletions
diff --git a/drivers/clk/socfpga/clk-gate-a10.c b/drivers/clk/socfpga/clk-gate-a10.c
new file mode 100644
index 0000000000..06f129c160
--- /dev/null
+++ b/drivers/clk/socfpga/clk-gate-a10.c
@@ -0,0 +1,121 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2015 Altera Corporation. All rights reserved
+ */
+#include <linux/slab.h>
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+
+#include "clk.h"
+
+#define streq(a, b) (strcmp((a), (b)) == 0)
+
+#define to_socfpga_gate_clk(p) container_of(p, struct socfpga_gate_clk, hw.hw)
+
+/* SDMMC Group for System Manager defines */
+#define SYSMGR_SDMMCGRP_CTRL_OFFSET 0x28
+
+static unsigned long socfpga_gate_clk_recalc_rate(struct clk_hw *hwclk,
+ unsigned long parent_rate)
+{
+ struct socfpga_gate_clk *socfpgaclk = to_socfpga_gate_clk(hwclk);
+ u32 div = 1, val;
+
+ if (socfpgaclk->fixed_div)
+ div = socfpgaclk->fixed_div;
+ else if (socfpgaclk->div_reg) {
+ val = readl(socfpgaclk->div_reg) >> socfpgaclk->shift;
+ val &= GENMASK(socfpgaclk->width - 1, 0);
+ div = (1 << val);
+ }
+
+ return parent_rate / div;
+}
+
+static struct clk_ops gateclk_ops = {
+ .recalc_rate = socfpga_gate_clk_recalc_rate,
+};
+
+static void __init __socfpga_gate_init(struct device_node *node,
+ const struct clk_ops *ops)
+{
+ u32 clk_gate[2];
+ u32 div_reg[3];
+ u32 fixed_div;
+ struct clk_hw *hw_clk;
+ struct socfpga_gate_clk *socfpga_clk;
+ const char *clk_name = node->name;
+ const char *parent_name[SOCFPGA_MAX_PARENTS];
+ struct clk_init_data init;
+ int rc;
+
+ socfpga_clk = kzalloc(sizeof(*socfpga_clk), GFP_KERNEL);
+ if (WARN_ON(!socfpga_clk))
+ return;
+
+ rc = of_property_read_u32_array(node, "clk-gate", clk_gate, 2);
+ if (rc)
+ clk_gate[0] = 0;
+
+ if (clk_gate[0]) {
+ socfpga_clk->hw.reg = clk_mgr_a10_base_addr + clk_gate[0];
+ socfpga_clk->hw.bit_idx = clk_gate[1];
+
+ gateclk_ops.enable = clk_gate_ops.enable;
+ gateclk_ops.disable = clk_gate_ops.disable;
+ }
+
+ rc = of_property_read_u32(node, "fixed-divider", &fixed_div);
+ if (rc)
+ socfpga_clk->fixed_div = 0;
+ else
+ socfpga_clk->fixed_div = fixed_div;
+
+ rc = of_property_read_u32_array(node, "div-reg", div_reg, 3);
+ if (!rc) {
+ socfpga_clk->div_reg = clk_mgr_a10_base_addr + div_reg[0];
+ socfpga_clk->shift = div_reg[1];
+ socfpga_clk->width = div_reg[2];
+ } else {
+ socfpga_clk->div_reg = NULL;
+ }
+
+ of_property_read_string(node, "clock-output-names", &clk_name);
+
+ init.name = clk_name;
+ init.ops = ops;
+ init.flags = 0;
+
+ init.num_parents = of_clk_parent_fill(node, parent_name, SOCFPGA_MAX_PARENTS);
+ init.parent_names = parent_name;
+ socfpga_clk->hw.hw.init = &init;
+ hw_clk = &socfpga_clk->hw.hw;
+
+ rc = clk_hw_register(NULL, hw_clk);
+ if (rc) {
+ pr_err("Could not register clock:%s\n", clk_name);
+ goto err_clk_hw_register;
+ }
+
+ rc = of_clk_add_hw_provider(node, of_clk_hw_simple_get, hw_clk);
+ if (rc) {
+ pr_err("Could not register clock provider for node:%s\n",
+ clk_name);
+ goto err_of_clk_add_hw_provider;
+ }
+
+ return;
+
+err_of_clk_add_hw_provider:
+ clk_hw_unregister(hw_clk);
+err_clk_hw_register:
+ kfree(socfpga_clk);
+}
+
+void __init socfpga_a10_gate_init(struct device_node *node)
+{
+ __socfpga_gate_init(node, &gateclk_ops);
+}