1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * PLL clock driver for Keystone devices
4 *
5 * Copyright (C) 2013 Texas Instruments Inc.
6 * Murali Karicheri <m-karicheri2@ti.com>
7 * Santosh Shilimkar <santosh.shilimkar@ti.com>
8 */
9#include <linux/clk-provider.h>
10#include <linux/err.h>
11#include <linux/io.h>
12#include <linux/slab.h>
13#include <linux/of_address.h>
14#include <linux/of.h>
15#include <linux/module.h>
16
17#define PLLM_LOW_MASK 0x3f
18#define PLLM_HIGH_MASK 0x7ffc0
19#define MAIN_PLLM_HIGH_MASK 0x7f000
20#define PLLM_HIGH_SHIFT 6
21#define PLLD_MASK 0x3f
22#define CLKOD_MASK 0x780000
23#define CLKOD_SHIFT 19
24
25/**
26 * struct clk_pll_data - pll data structure
27 * @has_pllctrl: If set to non zero, lower 6 bits of multiplier is in pllm
28 * register of pll controller, else it is in the pll_ctrl0((bit 11-6)
29 * @phy_pllm: Physical address of PLLM in pll controller. Used when
30 * has_pllctrl is non zero.
31 * @phy_pll_ctl0: Physical address of PLL ctrl0. This could be that of
32 * Main PLL or any other PLLs in the device such as ARM PLL, DDR PLL
33 * or PA PLL available on keystone2. These PLLs are controlled by
34 * this register. Main PLL is controlled by a PLL controller.
35 * @pllm: PLL register map address for multiplier bits
36 * @pllod: PLL register map address for post divider bits
37 * @pll_ctl0: PLL controller map address
38 * @pllm_lower_mask: multiplier lower mask
39 * @pllm_upper_mask: multiplier upper mask
40 * @pllm_upper_shift: multiplier upper shift
41 * @plld_mask: divider mask
42 * @clkod_mask: output divider mask
43 * @clkod_shift: output divider shift
44 * @plld_mask: divider mask
45 * @postdiv: Fixed post divider
46 */
47struct clk_pll_data {
48 bool has_pllctrl;
49 u32 phy_pllm;
50 u32 phy_pll_ctl0;
51 void __iomem *pllm;
52 void __iomem *pllod;
53 void __iomem *pll_ctl0;
54 u32 pllm_lower_mask;
55 u32 pllm_upper_mask;
56 u32 pllm_upper_shift;
57 u32 plld_mask;
58 u32 clkod_mask;
59 u32 clkod_shift;
60 u32 postdiv;
61};
62
63/**
64 * struct clk_pll - Main pll clock
65 * @hw: clk_hw for the pll
66 * @pll_data: PLL driver specific data
67 */
68struct clk_pll {
69 struct clk_hw hw;
70 struct clk_pll_data *pll_data;
71};
72
73#define to_clk_pll(_hw) container_of(_hw, struct clk_pll, hw)
74
75static unsigned long clk_pllclk_recalc(struct clk_hw *hw,
76 unsigned long parent_rate)
77{
78 struct clk_pll *pll = to_clk_pll(hw);
79 struct clk_pll_data *pll_data = pll->pll_data;
80 unsigned long rate = parent_rate;
81 u32 mult = 0, prediv, postdiv, val;
82
83 /*
84 * get bits 0-5 of multiplier from pllctrl PLLM register
85 * if has_pllctrl is non zero
86 */
87 if (pll_data->has_pllctrl) {
88 val = readl(addr: pll_data->pllm);
89 mult = (val & pll_data->pllm_lower_mask);
90 }
91
92 /* bit6-12 of PLLM is in Main PLL control register */
93 val = readl(addr: pll_data->pll_ctl0);
94 mult |= ((val & pll_data->pllm_upper_mask)
95 >> pll_data->pllm_upper_shift);
96 prediv = (val & pll_data->plld_mask);
97
98 if (!pll_data->has_pllctrl)
99 /* read post divider from od bits*/
100 postdiv = ((val & pll_data->clkod_mask) >>
101 pll_data->clkod_shift) + 1;
102 else if (pll_data->pllod) {
103 postdiv = readl(addr: pll_data->pllod);
104 postdiv = ((postdiv & pll_data->clkod_mask) >>
105 pll_data->clkod_shift) + 1;
106 } else
107 postdiv = pll_data->postdiv;
108
109 rate /= (prediv + 1);
110 rate = (rate * (mult + 1));
111 rate /= postdiv;
112
113 return rate;
114}
115
116static const struct clk_ops clk_pll_ops = {
117 .recalc_rate = clk_pllclk_recalc,
118};
119
120static struct clk *clk_register_pll(struct device *dev,
121 const char *name,
122 const char *parent_name,
123 struct clk_pll_data *pll_data)
124{
125 struct clk_init_data init;
126 struct clk_pll *pll;
127 struct clk *clk;
128
129 pll = kzalloc(size: sizeof(*pll), GFP_KERNEL);
130 if (!pll)
131 return ERR_PTR(error: -ENOMEM);
132
133 init.name = name;
134 init.ops = &clk_pll_ops;
135 init.flags = 0;
136 init.parent_names = (parent_name ? &parent_name : NULL);
137 init.num_parents = (parent_name ? 1 : 0);
138
139 pll->pll_data = pll_data;
140 pll->hw.init = &init;
141
142 clk = clk_register(NULL, hw: &pll->hw);
143 if (IS_ERR(ptr: clk))
144 goto out;
145
146 return clk;
147out:
148 kfree(objp: pll);
149 return NULL;
150}
151
152/**
153 * _of_pll_clk_init - PLL initialisation via DT
154 * @node: device tree node for this clock
155 * @pllctrl: If true, lower 6 bits of multiplier is in pllm register of
156 * pll controller, else it is in the control register0(bit 11-6)
157 */
158static void __init _of_pll_clk_init(struct device_node *node, bool pllctrl)
159{
160 struct clk_pll_data *pll_data;
161 const char *parent_name;
162 struct clk *clk;
163 int i;
164
165 pll_data = kzalloc(size: sizeof(*pll_data), GFP_KERNEL);
166 if (!pll_data) {
167 pr_err("%s: Out of memory\n", __func__);
168 return;
169 }
170
171 parent_name = of_clk_get_parent_name(np: node, index: 0);
172 if (of_property_read_u32(np: node, propname: "fixed-postdiv", out_value: &pll_data->postdiv)) {
173 /* assume the PLL has output divider register bits */
174 pll_data->clkod_mask = CLKOD_MASK;
175 pll_data->clkod_shift = CLKOD_SHIFT;
176
177 /*
178 * Check if there is an post-divider register. If not
179 * assume od bits are part of control register.
180 */
181 i = of_property_match_string(np: node, propname: "reg-names",
182 string: "post-divider");
183 pll_data->pllod = of_iomap(node, index: i);
184 }
185
186 i = of_property_match_string(np: node, propname: "reg-names", string: "control");
187 pll_data->pll_ctl0 = of_iomap(node, index: i);
188 if (!pll_data->pll_ctl0) {
189 pr_err("%s: ioremap failed\n", __func__);
190 iounmap(addr: pll_data->pllod);
191 goto out;
192 }
193
194 pll_data->pllm_lower_mask = PLLM_LOW_MASK;
195 pll_data->pllm_upper_shift = PLLM_HIGH_SHIFT;
196 pll_data->plld_mask = PLLD_MASK;
197 pll_data->has_pllctrl = pllctrl;
198 if (!pll_data->has_pllctrl) {
199 pll_data->pllm_upper_mask = PLLM_HIGH_MASK;
200 } else {
201 pll_data->pllm_upper_mask = MAIN_PLLM_HIGH_MASK;
202 i = of_property_match_string(np: node, propname: "reg-names", string: "multiplier");
203 pll_data->pllm = of_iomap(node, index: i);
204 if (!pll_data->pllm) {
205 iounmap(addr: pll_data->pll_ctl0);
206 iounmap(addr: pll_data->pllod);
207 goto out;
208 }
209 }
210
211 clk = clk_register_pll(NULL, name: node->name, parent_name, pll_data);
212 if (!IS_ERR_OR_NULL(ptr: clk)) {
213 of_clk_add_provider(np: node, clk_src_get: of_clk_src_simple_get, data: clk);
214 return;
215 }
216
217out:
218 pr_err("%s: error initializing pll %pOFn\n", __func__, node);
219 kfree(objp: pll_data);
220}
221
222/**
223 * of_keystone_pll_clk_init - PLL initialisation DT wrapper
224 * @node: device tree node for this clock
225 */
226static void __init of_keystone_pll_clk_init(struct device_node *node)
227{
228 _of_pll_clk_init(node, pllctrl: false);
229}
230CLK_OF_DECLARE(keystone_pll_clock, "ti,keystone,pll-clock",
231 of_keystone_pll_clk_init);
232
233/**
234 * of_keystone_main_pll_clk_init - Main PLL initialisation DT wrapper
235 * @node: device tree node for this clock
236 */
237static void __init of_keystone_main_pll_clk_init(struct device_node *node)
238{
239 _of_pll_clk_init(node, pllctrl: true);
240}
241CLK_OF_DECLARE(keystone_main_pll_clock, "ti,keystone,main-pll-clock",
242 of_keystone_main_pll_clk_init);
243
244/**
245 * of_pll_div_clk_init - PLL divider setup function
246 * @node: device tree node for this clock
247 */
248static void __init of_pll_div_clk_init(struct device_node *node)
249{
250 const char *parent_name;
251 void __iomem *reg;
252 u32 shift, mask;
253 struct clk *clk;
254 const char *clk_name = node->name;
255
256 of_property_read_string(np: node, propname: "clock-output-names", out_string: &clk_name);
257 reg = of_iomap(node, index: 0);
258 if (!reg) {
259 pr_err("%s: ioremap failed\n", __func__);
260 return;
261 }
262
263 parent_name = of_clk_get_parent_name(np: node, index: 0);
264 if (!parent_name) {
265 pr_err("%s: missing parent clock\n", __func__);
266 iounmap(addr: reg);
267 return;
268 }
269
270 if (of_property_read_u32(np: node, propname: "bit-shift", out_value: &shift)) {
271 pr_err("%s: missing 'shift' property\n", __func__);
272 iounmap(addr: reg);
273 return;
274 }
275
276 if (of_property_read_u32(np: node, propname: "bit-mask", out_value: &mask)) {
277 pr_err("%s: missing 'bit-mask' property\n", __func__);
278 iounmap(addr: reg);
279 return;
280 }
281
282 clk = clk_register_divider(NULL, clk_name, parent_name, 0, reg, shift,
283 mask, 0, NULL);
284 if (IS_ERR(ptr: clk)) {
285 pr_err("%s: error registering divider %s\n", __func__, clk_name);
286 iounmap(addr: reg);
287 return;
288 }
289
290 of_clk_add_provider(np: node, clk_src_get: of_clk_src_simple_get, data: clk);
291}
292CLK_OF_DECLARE(pll_divider_clock, "ti,keystone,pll-divider-clock", of_pll_div_clk_init);
293
294/**
295 * of_pll_mux_clk_init - PLL mux setup function
296 * @node: device tree node for this clock
297 */
298static void __init of_pll_mux_clk_init(struct device_node *node)
299{
300 void __iomem *reg;
301 u32 shift, mask;
302 struct clk *clk;
303 const char *parents[2];
304 const char *clk_name = node->name;
305
306 of_property_read_string(np: node, propname: "clock-output-names", out_string: &clk_name);
307 reg = of_iomap(node, index: 0);
308 if (!reg) {
309 pr_err("%s: ioremap failed\n", __func__);
310 return;
311 }
312
313 of_clk_parent_fill(np: node, parents, size: 2);
314 if (!parents[0] || !parents[1]) {
315 pr_err("%s: missing parent clocks\n", __func__);
316 return;
317 }
318
319 if (of_property_read_u32(np: node, propname: "bit-shift", out_value: &shift)) {
320 pr_err("%s: missing 'shift' property\n", __func__);
321 return;
322 }
323
324 if (of_property_read_u32(np: node, propname: "bit-mask", out_value: &mask)) {
325 pr_err("%s: missing 'bit-mask' property\n", __func__);
326 return;
327 }
328
329 clk = clk_register_mux(NULL, clk_name, (const char **)&parents,
330 ARRAY_SIZE(parents) , 0, reg, shift, mask,
331 0, NULL);
332 if (IS_ERR(ptr: clk)) {
333 pr_err("%s: error registering mux %s\n", __func__, clk_name);
334 return;
335 }
336
337 of_clk_add_provider(np: node, clk_src_get: of_clk_src_simple_get, data: clk);
338}
339CLK_OF_DECLARE(pll_mux_clock, "ti,keystone,pll-mux-clock", of_pll_mux_clk_init);
340
341MODULE_LICENSE("GPL");
342MODULE_DESCRIPTION("PLL clock driver for Keystone devices");
343MODULE_AUTHOR("Murali Karicheri <m-karicheri2@ti.com>");
344MODULE_AUTHOR("Santosh Shilimkar <santosh.shilimkar@ti.com>");
345

source code of linux/drivers/clk/keystone/pll.c