1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright 2011-2012 Calxeda, Inc.
4 * Copyright (C) 2012-2013 Altera Corporation <www.altera.com>
5 *
6 * Based from clk-highbank.c
7 */
8 #include <linux/slab.h>
9 #include <linux/clk-provider.h>
10 #include <linux/io.h>
11 #include <linux/mfd/syscon.h>
12 #include <linux/of.h>
13 #include <linux/regmap.h>
14
15 #include "clk.h"
16
17 #define SOCFPGA_L4_MP_CLK "l4_mp_clk"
18 #define SOCFPGA_L4_SP_CLK "l4_sp_clk"
19 #define SOCFPGA_NAND_CLK "nand_clk"
20 #define SOCFPGA_NAND_X_CLK "nand_x_clk"
21 #define SOCFPGA_MMC_CLK "sdmmc_clk"
22 #define SOCFPGA_GPIO_DB_CLK_OFFSET 0xA8
23
24 #define to_socfpga_gate_clk(p) container_of(p, struct socfpga_gate_clk, hw.hw)
25
26 /* SDMMC Group for System Manager defines */
27 #define SYSMGR_SDMMCGRP_CTRL_OFFSET 0x108
28
socfpga_clk_get_parent(struct clk_hw * hwclk)29 static u8 socfpga_clk_get_parent(struct clk_hw *hwclk)
30 {
31 u32 l4_src;
32 u32 perpll_src;
33 const char *name = clk_hw_get_name(hwclk);
34
35 if (streq(name, SOCFPGA_L4_MP_CLK)) {
36 l4_src = readl(clk_mgr_base_addr + CLKMGR_L4SRC);
37 return l4_src & 0x1;
38 }
39 if (streq(name, SOCFPGA_L4_SP_CLK)) {
40 l4_src = readl(clk_mgr_base_addr + CLKMGR_L4SRC);
41 return !!(l4_src & 2);
42 }
43
44 perpll_src = readl(clk_mgr_base_addr + CLKMGR_PERPLL_SRC);
45 if (streq(name, SOCFPGA_MMC_CLK))
46 return perpll_src & 0x3;
47 if (streq(name, SOCFPGA_NAND_CLK) ||
48 streq(name, SOCFPGA_NAND_X_CLK))
49 return (perpll_src >> 2) & 3;
50
51 /* QSPI clock */
52 return (perpll_src >> 4) & 3;
53
54 }
55
socfpga_clk_set_parent(struct clk_hw * hwclk,u8 parent)56 static int socfpga_clk_set_parent(struct clk_hw *hwclk, u8 parent)
57 {
58 u32 src_reg;
59 const char *name = clk_hw_get_name(hwclk);
60
61 if (streq(name, SOCFPGA_L4_MP_CLK)) {
62 src_reg = readl(clk_mgr_base_addr + CLKMGR_L4SRC);
63 src_reg &= ~0x1;
64 src_reg |= parent;
65 writel(src_reg, clk_mgr_base_addr + CLKMGR_L4SRC);
66 } else if (streq(name, SOCFPGA_L4_SP_CLK)) {
67 src_reg = readl(clk_mgr_base_addr + CLKMGR_L4SRC);
68 src_reg &= ~0x2;
69 src_reg |= (parent << 1);
70 writel(src_reg, clk_mgr_base_addr + CLKMGR_L4SRC);
71 } else {
72 src_reg = readl(clk_mgr_base_addr + CLKMGR_PERPLL_SRC);
73 if (streq(name, SOCFPGA_MMC_CLK)) {
74 src_reg &= ~0x3;
75 src_reg |= parent;
76 } else if (streq(name, SOCFPGA_NAND_CLK) ||
77 streq(name, SOCFPGA_NAND_X_CLK)) {
78 src_reg &= ~0xC;
79 src_reg |= (parent << 2);
80 } else {/* QSPI clock */
81 src_reg &= ~0x30;
82 src_reg |= (parent << 4);
83 }
84 writel(src_reg, clk_mgr_base_addr + CLKMGR_PERPLL_SRC);
85 }
86
87 return 0;
88 }
89
socfpga_clk_recalc_rate(struct clk_hw * hwclk,unsigned long parent_rate)90 static unsigned long socfpga_clk_recalc_rate(struct clk_hw *hwclk,
91 unsigned long parent_rate)
92 {
93 struct socfpga_gate_clk *socfpgaclk = to_socfpga_gate_clk(hwclk);
94 u32 div = 1, val;
95
96 if (socfpgaclk->fixed_div)
97 div = socfpgaclk->fixed_div;
98 else if (socfpgaclk->div_reg) {
99 val = readl(socfpgaclk->div_reg) >> socfpgaclk->shift;
100 val &= GENMASK(socfpgaclk->width - 1, 0);
101 /* Check for GPIO_DB_CLK by its offset */
102 if ((uintptr_t) socfpgaclk->div_reg & SOCFPGA_GPIO_DB_CLK_OFFSET)
103 div = val + 1;
104 else
105 div = (1 << val);
106 }
107
108 return parent_rate / div;
109 }
110
socfpga_clk_prepare(struct clk_hw * hwclk)111 static int socfpga_clk_prepare(struct clk_hw *hwclk)
112 {
113 struct socfpga_gate_clk *socfpgaclk = to_socfpga_gate_clk(hwclk);
114 struct regmap *sys_mgr_base_addr;
115 int i;
116 u32 hs_timing;
117 u32 clk_phase[2];
118
119 if (socfpgaclk->clk_phase[0] || socfpgaclk->clk_phase[1]) {
120 sys_mgr_base_addr = syscon_regmap_lookup_by_compatible("altr,sys-mgr");
121 if (IS_ERR(sys_mgr_base_addr)) {
122 pr_err("%s: failed to find altr,sys-mgr regmap!\n", __func__);
123 return -EINVAL;
124 }
125
126 for (i = 0; i < 2; i++) {
127 switch (socfpgaclk->clk_phase[i]) {
128 case 0:
129 clk_phase[i] = 0;
130 break;
131 case 45:
132 clk_phase[i] = 1;
133 break;
134 case 90:
135 clk_phase[i] = 2;
136 break;
137 case 135:
138 clk_phase[i] = 3;
139 break;
140 case 180:
141 clk_phase[i] = 4;
142 break;
143 case 225:
144 clk_phase[i] = 5;
145 break;
146 case 270:
147 clk_phase[i] = 6;
148 break;
149 case 315:
150 clk_phase[i] = 7;
151 break;
152 default:
153 clk_phase[i] = 0;
154 break;
155 }
156 }
157 hs_timing = SYSMGR_SDMMC_CTRL_SET(clk_phase[0], clk_phase[1]);
158 regmap_write(sys_mgr_base_addr, SYSMGR_SDMMCGRP_CTRL_OFFSET,
159 hs_timing);
160 }
161 return 0;
162 }
163
164 static struct clk_ops gateclk_ops = {
165 .prepare = socfpga_clk_prepare,
166 .recalc_rate = socfpga_clk_recalc_rate,
167 .get_parent = socfpga_clk_get_parent,
168 .set_parent = socfpga_clk_set_parent,
169 };
170
socfpga_gate_init(struct device_node * node)171 void __init socfpga_gate_init(struct device_node *node)
172 {
173 u32 clk_gate[2];
174 u32 div_reg[3];
175 u32 clk_phase[2];
176 u32 fixed_div;
177 struct clk_hw *hw_clk;
178 struct socfpga_gate_clk *socfpga_clk;
179 const char *clk_name = node->name;
180 const char *parent_name[SOCFPGA_MAX_PARENTS];
181 struct clk_init_data init;
182 struct clk_ops *ops;
183 int rc;
184 int err;
185
186 socfpga_clk = kzalloc(sizeof(*socfpga_clk), GFP_KERNEL);
187 if (WARN_ON(!socfpga_clk))
188 return;
189
190 ops = kmemdup(&gateclk_ops, sizeof(gateclk_ops), GFP_KERNEL);
191 if (WARN_ON(!ops)) {
192 kfree(socfpga_clk);
193 return;
194 }
195
196 rc = of_property_read_u32_array(node, "clk-gate", clk_gate, 2);
197 if (rc)
198 clk_gate[0] = 0;
199
200 if (clk_gate[0]) {
201 socfpga_clk->hw.reg = clk_mgr_base_addr + clk_gate[0];
202 socfpga_clk->hw.bit_idx = clk_gate[1];
203
204 ops->enable = clk_gate_ops.enable;
205 ops->disable = clk_gate_ops.disable;
206 }
207
208 rc = of_property_read_u32(node, "fixed-divider", &fixed_div);
209 if (rc)
210 socfpga_clk->fixed_div = 0;
211 else
212 socfpga_clk->fixed_div = fixed_div;
213
214 rc = of_property_read_u32_array(node, "div-reg", div_reg, 3);
215 if (!rc) {
216 socfpga_clk->div_reg = clk_mgr_base_addr + div_reg[0];
217 socfpga_clk->shift = div_reg[1];
218 socfpga_clk->width = div_reg[2];
219 } else {
220 socfpga_clk->div_reg = NULL;
221 }
222
223 rc = of_property_read_u32_array(node, "clk-phase", clk_phase, 2);
224 if (!rc) {
225 socfpga_clk->clk_phase[0] = clk_phase[0];
226 socfpga_clk->clk_phase[1] = clk_phase[1];
227 }
228
229 of_property_read_string(node, "clock-output-names", &clk_name);
230
231 init.name = clk_name;
232 init.ops = ops;
233 init.flags = 0;
234
235 init.num_parents = of_clk_parent_fill(node, parent_name, SOCFPGA_MAX_PARENTS);
236 if (init.num_parents < 2) {
237 ops->get_parent = NULL;
238 ops->set_parent = NULL;
239 }
240
241 init.parent_names = parent_name;
242 socfpga_clk->hw.hw.init = &init;
243
244 hw_clk = &socfpga_clk->hw.hw;
245
246 err = clk_hw_register(NULL, hw_clk);
247 if (err) {
248 kfree(ops);
249 kfree(socfpga_clk);
250 return;
251 }
252 rc = of_clk_add_provider(node, of_clk_src_simple_get, hw_clk);
253 if (WARN_ON(rc))
254 return;
255 }
256