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path: root/drivers/clk/socfpga/clk-gate.c
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Diffstat (limited to 'drivers/clk/socfpga/clk-gate.c')
-rw-r--r--drivers/clk/socfpga/clk-gate.c263
1 files changed, 263 insertions, 0 deletions
diff --git a/drivers/clk/socfpga/clk-gate.c b/drivers/clk/socfpga/clk-gate.c
new file mode 100644
index 000000000000..501d513bf890
--- /dev/null
+++ b/drivers/clk/socfpga/clk-gate.c
@@ -0,0 +1,263 @@
+/*
+ * Copyright 2011-2012 Calxeda, Inc.
+ * Copyright (C) 2012-2013 Altera Corporation <www.altera.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that 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.
+ *
+ * Based from clk-highbank.c
+ *
+ */
+#include <linux/clk.h>
+#include <linux/clkdev.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 SOCFPGA_L4_MP_CLK "l4_mp_clk"
+#define SOCFPGA_L4_SP_CLK "l4_sp_clk"
+#define SOCFPGA_NAND_CLK "nand_clk"
+#define SOCFPGA_NAND_X_CLK "nand_x_clk"
+#define SOCFPGA_MMC_CLK "sdmmc_clk"
+#define SOCFPGA_GPIO_DB_CLK_OFFSET 0xA8
+
+#define div_mask(width) ((1 << (width)) - 1)
+#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 0x108
+#define SYSMGR_SDMMC_CTRL_SET(smplsel, drvsel) \
+ ((((smplsel) & 0x7) << 3) | (((drvsel) & 0x7) << 0))
+
+static u8 socfpga_clk_get_parent(struct clk_hw *hwclk)
+{
+ u32 l4_src;
+ u32 perpll_src;
+
+ if (streq(hwclk->init->name, SOCFPGA_L4_MP_CLK)) {
+ l4_src = readl(clk_mgr_base_addr + CLKMGR_L4SRC);
+ return l4_src &= 0x1;
+ }
+ if (streq(hwclk->init->name, SOCFPGA_L4_SP_CLK)) {
+ l4_src = readl(clk_mgr_base_addr + CLKMGR_L4SRC);
+ return !!(l4_src & 2);
+ }
+
+ perpll_src = readl(clk_mgr_base_addr + CLKMGR_PERPLL_SRC);
+ if (streq(hwclk->init->name, SOCFPGA_MMC_CLK))
+ return perpll_src &= 0x3;
+ if (streq(hwclk->init->name, SOCFPGA_NAND_CLK) ||
+ streq(hwclk->init->name, SOCFPGA_NAND_X_CLK))
+ return (perpll_src >> 2) & 3;
+
+ /* QSPI clock */
+ return (perpll_src >> 4) & 3;
+
+}
+
+static int socfpga_clk_set_parent(struct clk_hw *hwclk, u8 parent)
+{
+ u32 src_reg;
+
+ if (streq(hwclk->init->name, SOCFPGA_L4_MP_CLK)) {
+ src_reg = readl(clk_mgr_base_addr + CLKMGR_L4SRC);
+ src_reg &= ~0x1;
+ src_reg |= parent;
+ writel(src_reg, clk_mgr_base_addr + CLKMGR_L4SRC);
+ } else if (streq(hwclk->init->name, SOCFPGA_L4_SP_CLK)) {
+ src_reg = readl(clk_mgr_base_addr + CLKMGR_L4SRC);
+ src_reg &= ~0x2;
+ src_reg |= (parent << 1);
+ writel(src_reg, clk_mgr_base_addr + CLKMGR_L4SRC);
+ } else {
+ src_reg = readl(clk_mgr_base_addr + CLKMGR_PERPLL_SRC);
+ if (streq(hwclk->init->name, SOCFPGA_MMC_CLK)) {
+ src_reg &= ~0x3;
+ src_reg |= parent;
+ } else if (streq(hwclk->init->name, SOCFPGA_NAND_CLK) ||
+ streq(hwclk->init->name, SOCFPGA_NAND_X_CLK)) {
+ src_reg &= ~0xC;
+ src_reg |= (parent << 2);
+ } else {/* QSPI clock */
+ src_reg &= ~0x30;
+ src_reg |= (parent << 4);
+ }
+ writel(src_reg, clk_mgr_base_addr + CLKMGR_PERPLL_SRC);
+ }
+
+ return 0;
+}
+
+static unsigned long socfpga_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);
+ /* Check for GPIO_DB_CLK by its offset */
+ if ((int) socfpgaclk->div_reg & SOCFPGA_GPIO_DB_CLK_OFFSET)
+ div = val + 1;
+ else
+ 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);
+ struct regmap *sys_mgr_base_addr;
+ int i;
+ u32 hs_timing;
+ u32 clk_phase[2];
+
+ if (socfpgaclk->clk_phase[0] || socfpgaclk->clk_phase[1]) {
+ sys_mgr_base_addr = syscon_regmap_lookup_by_compatible("altr,sys-mgr");
+ if (IS_ERR(sys_mgr_base_addr)) {
+ pr_err("%s: failed to find altr,sys-mgr regmap!\n", __func__);
+ return -EINVAL;
+ }
+
+ for (i = 0; i < 2; 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]);
+ regmap_write(sys_mgr_base_addr, SYSMGR_SDMMCGRP_CTRL_OFFSET,
+ hs_timing);
+ }
+ return 0;
+}
+
+static struct clk_ops gateclk_ops = {
+ .prepare = socfpga_clk_prepare,
+ .recalc_rate = socfpga_clk_recalc_rate,
+ .get_parent = socfpga_clk_get_parent,
+ .set_parent = socfpga_clk_set_parent,
+};
+
+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_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_base_addr + div_reg[0];
+ socfpga_clk->shift = div_reg[1];
+ socfpga_clk->width = div_reg[2];
+ } else {
+ socfpga_clk->div_reg = 0;
+ }
+
+ 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];
+ }
+
+ 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_gate_init(struct device_node *node)
+{
+ __socfpga_gate_init(node, &gateclk_ops);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-17 02:08:18 +0000