1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2022 MediaTek Inc.
4 * Author: Edward-JW Yang <edward-jw.yang@mediatek.com>
5 */
6
7#include <linux/io.h>
8#include <linux/iopoll.h>
9
10#include "clk-mtk.h"
11#include "clk-pllfh.h"
12#include "clk-fhctl.h"
13
14#define PERCENT_TO_DDSLMT(dds, percent_m10) \
15 ((((dds) * (percent_m10)) >> 5) / 100)
16
17static const struct fhctl_offset fhctl_offset_v1 = {
18 .offset_hp_en = 0x0,
19 .offset_clk_con = 0x4,
20 .offset_rst_con = 0x8,
21 .offset_slope0 = 0xc,
22 .offset_slope1 = 0x10,
23 .offset_cfg = 0x0,
24 .offset_updnlmt = 0x4,
25 .offset_dds = 0x8,
26 .offset_dvfs = 0xc,
27 .offset_mon = 0x10,
28};
29
30static const struct fhctl_offset fhctl_offset_v2 = {
31 .offset_hp_en = 0x0,
32 .offset_clk_con = 0x8,
33 .offset_rst_con = 0xc,
34 .offset_slope0 = 0x10,
35 .offset_slope1 = 0x14,
36 .offset_cfg = 0x0,
37 .offset_updnlmt = 0x4,
38 .offset_dds = 0x8,
39 .offset_dvfs = 0xc,
40 .offset_mon = 0x10,
41};
42
43const struct fhctl_offset *fhctl_get_offset_table(enum fhctl_variant v)
44{
45 switch (v) {
46 case FHCTL_PLLFH_V1:
47 return &fhctl_offset_v1;
48 case FHCTL_PLLFH_V2:
49 return &fhctl_offset_v2;
50 default:
51 return ERR_PTR(error: -EINVAL);
52 };
53}
54
55static void dump_hw(struct mtk_clk_pll *pll, struct fh_pll_regs *regs,
56 const struct fh_pll_data *data)
57{
58 pr_info("hp_en<%x>,clk_con<%x>,slope0<%x>,slope1<%x>\n",
59 readl(regs->reg_hp_en), readl(regs->reg_clk_con),
60 readl(regs->reg_slope0), readl(regs->reg_slope1));
61 pr_info("cfg<%x>,lmt<%x>,dds<%x>,dvfs<%x>,mon<%x>\n",
62 readl(regs->reg_cfg), readl(regs->reg_updnlmt),
63 readl(regs->reg_dds), readl(regs->reg_dvfs),
64 readl(regs->reg_mon));
65 pr_info("pcw<%x>\n", readl(pll->pcw_addr));
66}
67
68static int fhctl_set_ssc_regs(struct mtk_clk_pll *pll, struct fh_pll_regs *regs,
69 const struct fh_pll_data *data, u32 rate)
70{
71 u32 updnlmt_val, r;
72
73 writel(val: (readl(addr: regs->reg_cfg) & ~(data->frddsx_en)), addr: regs->reg_cfg);
74 writel(val: (readl(addr: regs->reg_cfg) & ~(data->sfstrx_en)), addr: regs->reg_cfg);
75 writel(val: (readl(addr: regs->reg_cfg) & ~(data->fhctlx_en)), addr: regs->reg_cfg);
76
77 if (rate > 0) {
78 /* Set the relative parameter registers (dt/df/upbnd/downbnd) */
79 r = readl(addr: regs->reg_cfg);
80 r &= ~(data->msk_frddsx_dys);
81 r |= (data->df_val << (ffs(data->msk_frddsx_dys) - 1));
82 writel(val: r, addr: regs->reg_cfg);
83
84 r = readl(addr: regs->reg_cfg);
85 r &= ~(data->msk_frddsx_dts);
86 r |= (data->dt_val << (ffs(data->msk_frddsx_dts) - 1));
87 writel(val: r, addr: regs->reg_cfg);
88
89 writel(val: (readl(addr: pll->pcw_addr) & data->dds_mask) | data->tgl_org,
90 addr: regs->reg_dds);
91
92 /* Calculate UPDNLMT */
93 updnlmt_val = PERCENT_TO_DDSLMT((readl(regs->reg_dds) &
94 data->dds_mask), rate) <<
95 data->updnlmt_shft;
96
97 writel(val: updnlmt_val, addr: regs->reg_updnlmt);
98 writel(readl(addr: regs->reg_hp_en) | BIT(data->fh_id),
99 addr: regs->reg_hp_en);
100 /* Enable SSC */
101 writel(readl(addr: regs->reg_cfg) | data->frddsx_en, addr: regs->reg_cfg);
102 /* Enable Hopping control */
103 writel(readl(addr: regs->reg_cfg) | data->fhctlx_en, addr: regs->reg_cfg);
104
105 } else {
106 /* Switch to APMIXEDSYS control */
107 writel(readl(addr: regs->reg_hp_en) & ~BIT(data->fh_id),
108 addr: regs->reg_hp_en);
109 /* Wait for DDS to be stable */
110 udelay(30);
111 }
112
113 return 0;
114}
115
116static int hopping_hw_flow(struct mtk_clk_pll *pll, struct fh_pll_regs *regs,
117 const struct fh_pll_data *data,
118 struct fh_pll_state *state, unsigned int new_dds)
119{
120 u32 dds_mask = data->dds_mask;
121 u32 mon_dds = 0;
122 u32 con_pcw_tmp;
123 int ret;
124
125 if (state->ssc_rate)
126 fhctl_set_ssc_regs(pll, regs, data, rate: 0);
127
128 writel(val: (readl(addr: pll->pcw_addr) & dds_mask) | data->tgl_org,
129 addr: regs->reg_dds);
130
131 writel(readl(addr: regs->reg_cfg) | data->sfstrx_en, addr: regs->reg_cfg);
132 writel(readl(addr: regs->reg_cfg) | data->fhctlx_en, addr: regs->reg_cfg);
133 writel(val: data->slope0_value, addr: regs->reg_slope0);
134 writel(val: data->slope1_value, addr: regs->reg_slope1);
135
136 writel(readl(addr: regs->reg_hp_en) | BIT(data->fh_id), addr: regs->reg_hp_en);
137 writel(val: (new_dds) | (data->dvfs_tri), addr: regs->reg_dvfs);
138
139 /* Wait 1000 us until DDS stable */
140 ret = readl_poll_timeout_atomic(regs->reg_mon, mon_dds,
141 (mon_dds & dds_mask) == new_dds,
142 10, 1000);
143 if (ret) {
144 pr_warn("%s: FHCTL hopping timeout\n", pll->data->name);
145 dump_hw(pll, regs, data);
146 }
147
148 con_pcw_tmp = readl(addr: pll->pcw_addr) & (~dds_mask);
149 con_pcw_tmp = (con_pcw_tmp | (readl(addr: regs->reg_mon) & dds_mask) |
150 data->pcwchg);
151
152 writel(val: con_pcw_tmp, addr: pll->pcw_addr);
153 writel(readl(addr: regs->reg_hp_en) & ~BIT(data->fh_id), addr: regs->reg_hp_en);
154
155 if (state->ssc_rate)
156 fhctl_set_ssc_regs(pll, regs, data, rate: state->ssc_rate);
157
158 return ret;
159}
160
161static unsigned int __get_postdiv(struct mtk_clk_pll *pll)
162{
163 unsigned int regval;
164
165 regval = readl(addr: pll->pd_addr) >> pll->data->pd_shift;
166 regval &= POSTDIV_MASK;
167
168 return BIT(regval);
169}
170
171static void __set_postdiv(struct mtk_clk_pll *pll, unsigned int postdiv)
172{
173 unsigned int regval;
174
175 regval = readl(addr: pll->pd_addr);
176 regval &= ~(POSTDIV_MASK << pll->data->pd_shift);
177 regval |= (ffs(postdiv) - 1) << pll->data->pd_shift;
178 writel(val: regval, addr: pll->pd_addr);
179}
180
181static int fhctl_hopping(struct mtk_fh *fh, unsigned int new_dds,
182 unsigned int postdiv)
183{
184 const struct fh_pll_data *data = &fh->pllfh_data->data;
185 struct fh_pll_state *state = &fh->pllfh_data->state;
186 struct fh_pll_regs *regs = &fh->regs;
187 struct mtk_clk_pll *pll = &fh->clk_pll;
188 spinlock_t *lock = fh->lock;
189 unsigned int pll_postdiv;
190 unsigned long flags = 0;
191 int ret;
192
193 if (postdiv) {
194 pll_postdiv = __get_postdiv(pll);
195
196 if (postdiv > pll_postdiv)
197 __set_postdiv(pll, postdiv);
198 }
199
200 spin_lock_irqsave(lock, flags);
201
202 ret = hopping_hw_flow(pll, regs, data, state, new_dds);
203
204 spin_unlock_irqrestore(lock, flags);
205
206 if (postdiv && postdiv < pll_postdiv)
207 __set_postdiv(pll, postdiv);
208
209 return ret;
210}
211
212static int fhctl_ssc_enable(struct mtk_fh *fh, u32 rate)
213{
214 const struct fh_pll_data *data = &fh->pllfh_data->data;
215 struct fh_pll_state *state = &fh->pllfh_data->state;
216 struct fh_pll_regs *regs = &fh->regs;
217 struct mtk_clk_pll *pll = &fh->clk_pll;
218 spinlock_t *lock = fh->lock;
219 unsigned long flags = 0;
220
221 spin_lock_irqsave(lock, flags);
222
223 fhctl_set_ssc_regs(pll, regs, data, rate);
224 state->ssc_rate = rate;
225
226 spin_unlock_irqrestore(lock, flags);
227
228 return 0;
229}
230
231static const struct fh_operation fhctl_ops = {
232 .hopping = fhctl_hopping,
233 .ssc_enable = fhctl_ssc_enable,
234};
235
236const struct fh_operation *fhctl_get_ops(void)
237{
238 return &fhctl_ops;
239}
240
241void fhctl_hw_init(struct mtk_fh *fh)
242{
243 const struct fh_pll_data data = fh->pllfh_data->data;
244 struct fh_pll_state state = fh->pllfh_data->state;
245 struct fh_pll_regs regs = fh->regs;
246 u32 val;
247
248 /* initial hw register */
249 val = readl(addr: regs.reg_clk_con) | BIT(data.fh_id);
250 writel(val, addr: regs.reg_clk_con);
251
252 val = readl(addr: regs.reg_rst_con) & ~BIT(data.fh_id);
253 writel(val, addr: regs.reg_rst_con);
254 val = readl(addr: regs.reg_rst_con) | BIT(data.fh_id);
255 writel(val, addr: regs.reg_rst_con);
256
257 writel(val: 0x0, addr: regs.reg_cfg);
258 writel(val: 0x0, addr: regs.reg_updnlmt);
259 writel(val: 0x0, addr: regs.reg_dds);
260
261 /* enable ssc if needed */
262 if (state.ssc_rate)
263 fh->ops->ssc_enable(fh, state.ssc_rate);
264}
265

source code of linux/drivers/clk/mediatek/clk-fhctl.c