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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.c190
1 files changed, 190 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 000000000000..be3e998b85d0
--- /dev/null
+++ b/drivers/clk/socfpga/clk-gate-a10.c
@@ -0,0 +1,190 @@
+/*
+ * Copyright (C) 2015 Altera Corporation. All rights reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+#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 &= div_mask(socfpgaclk->width);
+ div = (1 << val);
+ }
+
+ return parent_rate / div;
+}
+
+static int socfpga_clk_prepare(struct clk_hw *hwclk)
+{
+ struct socfpga_gate_clk *socfpgaclk = to_socfpga_gate_clk(hwclk);
+ int i;
+ u32 hs_timing;
+ u32 clk_phase[2];
+
+ if (socfpgaclk->clk_phase[0] || socfpgaclk->clk_phase[1]) {
+ for (i = 0; i < ARRAY_SIZE(clk_phase); i++) {
+ switch (socfpgaclk->clk_phase[i]) {
+ case 0:
+ clk_phase[i] = 0;
+ break;
+ case 45:
+ clk_phase[i] = 1;
+ break;
+ case 90:
+ clk_phase[i] = 2;
+ break;
+ case 135:
+ clk_phase[i] = 3;
+ break;
+ case 180:
+ clk_phase[i] = 4;
+ break;
+ case 225:
+ clk_phase[i] = 5;
+ break;
+ case 270:
+ clk_phase[i] = 6;
+ break;
+ case 315:
+ clk_phase[i] = 7;
+ break;
+ default:
+ clk_phase[i] = 0;
+ break;
+ }
+ }
+
+ hs_timing = SYSMGR_SDMMC_CTRL_SET(clk_phase[0], clk_phase[1]);
+ if (!IS_ERR(socfpgaclk->sys_mgr_base_addr))
+ regmap_write(socfpgaclk->sys_mgr_base_addr,
+ SYSMGR_SDMMCGRP_CTRL_OFFSET, hs_timing);
+ else
+ pr_err("%s: cannot set clk_phase because sys_mgr_base_addr is not available!\n",
+ __func__);
+ }
+ return 0;
+}
+
+static struct clk_ops gateclk_ops = {
+ .prepare = socfpga_clk_prepare,
+ .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 clk_phase[2];
+ u32 fixed_div;
+ struct clk *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;
+ int i = 0;
+
+ 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;
+ }
+
+ rc = of_property_read_u32_array(node, "clk-phase", clk_phase, 2);
+ if (!rc) {
+ socfpga_clk->clk_phase[0] = clk_phase[0];
+ socfpga_clk->clk_phase[1] = clk_phase[1];
+
+ socfpga_clk->sys_mgr_base_addr =
+ syscon_regmap_lookup_by_compatible("altr,sys-mgr");
+ if (IS_ERR(socfpga_clk->sys_mgr_base_addr)) {
+ pr_err("%s: failed to find altr,sys-mgr regmap!\n",
+ __func__);
+ return;
+ }
+ }
+
+ of_property_read_string(node, "clock-output-names", &clk_name);
+
+ init.name = clk_name;
+ init.ops = ops;
+ init.flags = 0;
+ while (i < SOCFPGA_MAX_PARENTS && (parent_name[i] =
+ of_clk_get_parent_name(node, i)) != NULL)
+ i++;
+
+ init.parent_names = parent_name;
+ init.num_parents = i;
+ socfpga_clk->hw.hw.init = &init;
+
+ clk = clk_register(NULL, &socfpga_clk->hw.hw);
+ if (WARN_ON(IS_ERR(clk))) {
+ kfree(socfpga_clk);
+ return;
+ }
+ rc = of_clk_add_provider(node, of_clk_src_simple_get, clk);
+ if (WARN_ON(rc))
+ return;
+}
+
+void __init socfpga_a10_gate_init(struct device_node *node)
+{
+ __socfpga_gate_init(node, &gateclk_ops);
+}