1 #include <linux/kernel.h>
2 #include <linux/init.h>
3
4 #include "common.h"
5
6 #include "voltage.h"
7 #include "vp.h"
8 #include "prm-regbits-34xx.h"
9 #include "prm-regbits-44xx.h"
10 #include "prm44xx.h"
11
_vp_set_init_voltage(struct voltagedomain * voltdm,u32 volt)12 static u32 _vp_set_init_voltage(struct voltagedomain *voltdm, u32 volt)
13 {
14 struct omap_vp_instance *vp = voltdm->vp;
15 u32 vpconfig;
16 char vsel;
17
18 vsel = voltdm->pmic->uv_to_vsel(volt);
19
20 vpconfig = voltdm->read(vp->vpconfig);
21 vpconfig &= ~(vp->common->vpconfig_initvoltage_mask |
22 vp->common->vpconfig_forceupdate |
23 vp->common->vpconfig_initvdd);
24 vpconfig |= vsel << __ffs(vp->common->vpconfig_initvoltage_mask);
25 voltdm->write(vpconfig, vp->vpconfig);
26
27 /* Trigger initVDD value copy to voltage processor */
28 voltdm->write((vpconfig | vp->common->vpconfig_initvdd),
29 vp->vpconfig);
30
31 /* Clear initVDD copy trigger bit */
32 voltdm->write(vpconfig, vp->vpconfig);
33
34 return vpconfig;
35 }
36
37 /* Generic voltage init functions */
omap_vp_init(struct voltagedomain * voltdm)38 void __init omap_vp_init(struct voltagedomain *voltdm)
39 {
40 struct omap_vp_instance *vp = voltdm->vp;
41 u32 val, sys_clk_rate, timeout, waittime;
42 u32 vddmin, vddmax, vstepmin, vstepmax;
43
44 if (!voltdm->pmic || !voltdm->pmic->uv_to_vsel) {
45 pr_err("%s: No PMIC info for vdd_%s\n", __func__, voltdm->name);
46 return;
47 }
48
49 if (!voltdm->read || !voltdm->write) {
50 pr_err("%s: No read/write API for accessing vdd_%s regs\n",
51 __func__, voltdm->name);
52 return;
53 }
54
55 vp->enabled = false;
56
57 /* Divide to avoid overflow */
58 sys_clk_rate = voltdm->sys_clk.rate / 1000;
59
60 timeout = (sys_clk_rate * voltdm->pmic->vp_timeout_us) / 1000;
61 vddmin = voltdm->pmic->vp_vddmin;
62 vddmax = voltdm->pmic->vp_vddmax;
63
64 waittime = DIV_ROUND_UP(voltdm->pmic->step_size * sys_clk_rate,
65 1000 * voltdm->pmic->slew_rate);
66 vstepmin = voltdm->pmic->vp_vstepmin;
67 vstepmax = voltdm->pmic->vp_vstepmax;
68
69 /*
70 * VP_CONFIG: error gain is not set here, it will be updated
71 * on each scale, based on OPP.
72 */
73 val = (voltdm->pmic->vp_erroroffset <<
74 __ffs(voltdm->vp->common->vpconfig_erroroffset_mask)) |
75 vp->common->vpconfig_timeouten;
76 voltdm->write(val, vp->vpconfig);
77
78 /* VSTEPMIN */
79 val = (waittime << vp->common->vstepmin_smpswaittimemin_shift) |
80 (vstepmin << vp->common->vstepmin_stepmin_shift);
81 voltdm->write(val, vp->vstepmin);
82
83 /* VSTEPMAX */
84 val = (vstepmax << vp->common->vstepmax_stepmax_shift) |
85 (waittime << vp->common->vstepmax_smpswaittimemax_shift);
86 voltdm->write(val, vp->vstepmax);
87
88 /* VLIMITTO */
89 val = (vddmax << vp->common->vlimitto_vddmax_shift) |
90 (vddmin << vp->common->vlimitto_vddmin_shift) |
91 (timeout << vp->common->vlimitto_timeout_shift);
92 voltdm->write(val, vp->vlimitto);
93 }
94
omap_vp_update_errorgain(struct voltagedomain * voltdm,unsigned long target_volt)95 int omap_vp_update_errorgain(struct voltagedomain *voltdm,
96 unsigned long target_volt)
97 {
98 struct omap_volt_data *volt_data;
99
100 if (!voltdm->vp)
101 return -EINVAL;
102
103 /* Get volt_data corresponding to target_volt */
104 volt_data = omap_voltage_get_voltdata(voltdm, target_volt);
105 if (IS_ERR(volt_data))
106 return -EINVAL;
107
108 /* Setting vp errorgain based on the voltage */
109 voltdm->rmw(voltdm->vp->common->vpconfig_errorgain_mask,
110 volt_data->vp_errgain <<
111 __ffs(voltdm->vp->common->vpconfig_errorgain_mask),
112 voltdm->vp->vpconfig);
113
114 return 0;
115 }
116
117 /* VP force update method of voltage scaling */
omap_vp_forceupdate_scale(struct voltagedomain * voltdm,unsigned long target_volt)118 int omap_vp_forceupdate_scale(struct voltagedomain *voltdm,
119 unsigned long target_volt)
120 {
121 struct omap_vp_instance *vp = voltdm->vp;
122 u32 vpconfig;
123 u8 target_vsel, current_vsel;
124 int ret, timeout = 0;
125
126 ret = omap_vc_pre_scale(voltdm, target_volt, &target_vsel, ¤t_vsel);
127 if (ret)
128 return ret;
129
130 /*
131 * Clear all pending TransactionDone interrupt/status. Typical latency
132 * is <3us
133 */
134 while (timeout++ < VP_TRANXDONE_TIMEOUT) {
135 vp->common->ops->clear_txdone(vp->id);
136 if (!vp->common->ops->check_txdone(vp->id))
137 break;
138 udelay(1);
139 }
140 if (timeout >= VP_TRANXDONE_TIMEOUT) {
141 pr_warning("%s: vdd_%s TRANXDONE timeout exceeded."
142 "Voltage change aborted", __func__, voltdm->name);
143 return -ETIMEDOUT;
144 }
145
146 vpconfig = _vp_set_init_voltage(voltdm, target_volt);
147
148 /* Force update of voltage */
149 voltdm->write(vpconfig | vp->common->vpconfig_forceupdate,
150 voltdm->vp->vpconfig);
151
152 /*
153 * Wait for TransactionDone. Typical latency is <200us.
154 * Depends on SMPSWAITTIMEMIN/MAX and voltage change
155 */
156 timeout = 0;
157 omap_test_timeout(vp->common->ops->check_txdone(vp->id),
158 VP_TRANXDONE_TIMEOUT, timeout);
159 if (timeout >= VP_TRANXDONE_TIMEOUT)
160 pr_err("%s: vdd_%s TRANXDONE timeout exceeded."
161 "TRANXDONE never got set after the voltage update\n",
162 __func__, voltdm->name);
163
164 omap_vc_post_scale(voltdm, target_volt, target_vsel, current_vsel);
165
166 /*
167 * Disable TransactionDone interrupt , clear all status, clear
168 * control registers
169 */
170 timeout = 0;
171 while (timeout++ < VP_TRANXDONE_TIMEOUT) {
172 vp->common->ops->clear_txdone(vp->id);
173 if (!vp->common->ops->check_txdone(vp->id))
174 break;
175 udelay(1);
176 }
177
178 if (timeout >= VP_TRANXDONE_TIMEOUT)
179 pr_warning("%s: vdd_%s TRANXDONE timeout exceeded while trying"
180 "to clear the TRANXDONE status\n",
181 __func__, voltdm->name);
182
183 /* Clear force bit */
184 voltdm->write(vpconfig, vp->vpconfig);
185
186 return 0;
187 }
188
189 /**
190 * omap_vp_enable() - API to enable a particular VP
191 * @voltdm: pointer to the VDD whose VP is to be enabled.
192 *
193 * This API enables a particular voltage processor. Needed by the smartreflex
194 * class drivers.
195 */
omap_vp_enable(struct voltagedomain * voltdm)196 void omap_vp_enable(struct voltagedomain *voltdm)
197 {
198 struct omap_vp_instance *vp;
199 u32 vpconfig, volt;
200
201 if (!voltdm || IS_ERR(voltdm)) {
202 pr_warning("%s: VDD specified does not exist!\n", __func__);
203 return;
204 }
205
206 vp = voltdm->vp;
207 if (!voltdm->read || !voltdm->write) {
208 pr_err("%s: No read/write API for accessing vdd_%s regs\n",
209 __func__, voltdm->name);
210 return;
211 }
212
213 /* If VP is already enabled, do nothing. Return */
214 if (vp->enabled)
215 return;
216
217 volt = voltdm_get_voltage(voltdm);
218 if (!volt) {
219 pr_warning("%s: unable to find current voltage for %s\n",
220 __func__, voltdm->name);
221 return;
222 }
223
224 vpconfig = _vp_set_init_voltage(voltdm, volt);
225
226 /* Enable VP */
227 vpconfig |= vp->common->vpconfig_vpenable;
228 voltdm->write(vpconfig, vp->vpconfig);
229
230 vp->enabled = true;
231 }
232
233 /**
234 * omap_vp_disable() - API to disable a particular VP
235 * @voltdm: pointer to the VDD whose VP is to be disabled.
236 *
237 * This API disables a particular voltage processor. Needed by the smartreflex
238 * class drivers.
239 */
omap_vp_disable(struct voltagedomain * voltdm)240 void omap_vp_disable(struct voltagedomain *voltdm)
241 {
242 struct omap_vp_instance *vp;
243 u32 vpconfig;
244 int timeout;
245
246 if (!voltdm || IS_ERR(voltdm)) {
247 pr_warning("%s: VDD specified does not exist!\n", __func__);
248 return;
249 }
250
251 vp = voltdm->vp;
252 if (!voltdm->read || !voltdm->write) {
253 pr_err("%s: No read/write API for accessing vdd_%s regs\n",
254 __func__, voltdm->name);
255 return;
256 }
257
258 /* If VP is already disabled, do nothing. Return */
259 if (!vp->enabled) {
260 pr_warning("%s: Trying to disable VP for vdd_%s when"
261 "it is already disabled\n", __func__, voltdm->name);
262 return;
263 }
264
265 /* Disable VP */
266 vpconfig = voltdm->read(vp->vpconfig);
267 vpconfig &= ~vp->common->vpconfig_vpenable;
268 voltdm->write(vpconfig, vp->vpconfig);
269
270 /*
271 * Wait for VP idle Typical latency is <2us. Maximum latency is ~100us
272 */
273 omap_test_timeout((voltdm->read(vp->vstatus)),
274 VP_IDLE_TIMEOUT, timeout);
275
276 if (timeout >= VP_IDLE_TIMEOUT)
277 pr_warning("%s: vdd_%s idle timedout\n",
278 __func__, voltdm->name);
279
280 vp->enabled = false;
281
282 return;
283 }
284