xref: /openbmc/linux/arch/arm/mach-omap2/cm2xxx.c (revision e23feb16)
1 /*
2  * OMAP2xxx CM module functions
3  *
4  * Copyright (C) 2009 Nokia Corporation
5  * Copyright (C) 2008-2010, 2012 Texas Instruments, Inc.
6  * Paul Walmsley
7  * Rajendra Nayak <rnayak@ti.com>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/types.h>
16 #include <linux/delay.h>
17 #include <linux/errno.h>
18 #include <linux/err.h>
19 #include <linux/io.h>
20 
21 #include "soc.h"
22 #include "iomap.h"
23 #include "common.h"
24 #include "prm2xxx.h"
25 #include "cm.h"
26 #include "cm2xxx.h"
27 #include "cm-regbits-24xx.h"
28 #include "clockdomain.h"
29 
30 /* CM_AUTOIDLE_PLL.AUTO_* bit values for DPLLs */
31 #define DPLL_AUTOIDLE_DISABLE				0x0
32 #define OMAP2XXX_DPLL_AUTOIDLE_LOW_POWER_STOP		0x3
33 
34 /* CM_AUTOIDLE_PLL.AUTO_* bit values for APLLs (OMAP2xxx only) */
35 #define OMAP2XXX_APLL_AUTOIDLE_DISABLE			0x0
36 #define OMAP2XXX_APLL_AUTOIDLE_LOW_POWER_STOP		0x3
37 
38 /* CM_IDLEST_PLL bit value offset for APLLs (OMAP2xxx only) */
39 #define EN_APLL_LOCKED					3
40 
41 static const u8 omap2xxx_cm_idlest_offs[] = {
42 	CM_IDLEST1, CM_IDLEST2, OMAP2430_CM_IDLEST3, OMAP24XX_CM_IDLEST4
43 };
44 
45 /*
46  *
47  */
48 
49 static void _write_clktrctrl(u8 c, s16 module, u32 mask)
50 {
51 	u32 v;
52 
53 	v = omap2_cm_read_mod_reg(module, OMAP2_CM_CLKSTCTRL);
54 	v &= ~mask;
55 	v |= c << __ffs(mask);
56 	omap2_cm_write_mod_reg(v, module, OMAP2_CM_CLKSTCTRL);
57 }
58 
59 bool omap2xxx_cm_is_clkdm_in_hwsup(s16 module, u32 mask)
60 {
61 	u32 v;
62 
63 	v = omap2_cm_read_mod_reg(module, OMAP2_CM_CLKSTCTRL);
64 	v &= mask;
65 	v >>= __ffs(mask);
66 
67 	return (v == OMAP24XX_CLKSTCTRL_ENABLE_AUTO) ? 1 : 0;
68 }
69 
70 void omap2xxx_cm_clkdm_enable_hwsup(s16 module, u32 mask)
71 {
72 	_write_clktrctrl(OMAP24XX_CLKSTCTRL_ENABLE_AUTO, module, mask);
73 }
74 
75 void omap2xxx_cm_clkdm_disable_hwsup(s16 module, u32 mask)
76 {
77 	_write_clktrctrl(OMAP24XX_CLKSTCTRL_DISABLE_AUTO, module, mask);
78 }
79 
80 /*
81  * DPLL autoidle control
82  */
83 
84 static void _omap2xxx_set_dpll_autoidle(u8 m)
85 {
86 	u32 v;
87 
88 	v = omap2_cm_read_mod_reg(PLL_MOD, CM_AUTOIDLE);
89 	v &= ~OMAP24XX_AUTO_DPLL_MASK;
90 	v |= m << OMAP24XX_AUTO_DPLL_SHIFT;
91 	omap2_cm_write_mod_reg(v, PLL_MOD, CM_AUTOIDLE);
92 }
93 
94 void omap2xxx_cm_set_dpll_disable_autoidle(void)
95 {
96 	_omap2xxx_set_dpll_autoidle(OMAP2XXX_DPLL_AUTOIDLE_LOW_POWER_STOP);
97 }
98 
99 void omap2xxx_cm_set_dpll_auto_low_power_stop(void)
100 {
101 	_omap2xxx_set_dpll_autoidle(DPLL_AUTOIDLE_DISABLE);
102 }
103 
104 /*
105  * APLL control
106  */
107 
108 static void _omap2xxx_set_apll_autoidle(u8 m, u32 mask)
109 {
110 	u32 v;
111 
112 	v = omap2_cm_read_mod_reg(PLL_MOD, CM_AUTOIDLE);
113 	v &= ~mask;
114 	v |= m << __ffs(mask);
115 	omap2_cm_write_mod_reg(v, PLL_MOD, CM_AUTOIDLE);
116 }
117 
118 void omap2xxx_cm_set_apll54_disable_autoidle(void)
119 {
120 	_omap2xxx_set_apll_autoidle(OMAP2XXX_APLL_AUTOIDLE_LOW_POWER_STOP,
121 				    OMAP24XX_AUTO_54M_MASK);
122 }
123 
124 void omap2xxx_cm_set_apll54_auto_low_power_stop(void)
125 {
126 	_omap2xxx_set_apll_autoidle(OMAP2XXX_APLL_AUTOIDLE_DISABLE,
127 				    OMAP24XX_AUTO_54M_MASK);
128 }
129 
130 void omap2xxx_cm_set_apll96_disable_autoidle(void)
131 {
132 	_omap2xxx_set_apll_autoidle(OMAP2XXX_APLL_AUTOIDLE_LOW_POWER_STOP,
133 				    OMAP24XX_AUTO_96M_MASK);
134 }
135 
136 void omap2xxx_cm_set_apll96_auto_low_power_stop(void)
137 {
138 	_omap2xxx_set_apll_autoidle(OMAP2XXX_APLL_AUTOIDLE_DISABLE,
139 				    OMAP24XX_AUTO_96M_MASK);
140 }
141 
142 /* Enable an APLL if off */
143 static int _omap2xxx_apll_enable(u8 enable_bit, u8 status_bit)
144 {
145 	u32 v, m;
146 
147 	m = EN_APLL_LOCKED << enable_bit;
148 
149 	v = omap2_cm_read_mod_reg(PLL_MOD, CM_CLKEN);
150 	if (v & m)
151 		return 0;   /* apll already enabled */
152 
153 	v |= m;
154 	omap2_cm_write_mod_reg(v, PLL_MOD, CM_CLKEN);
155 
156 	omap2xxx_cm_wait_module_ready(PLL_MOD, 1, status_bit);
157 
158 	/*
159 	 * REVISIT: Should we return an error code if
160 	 * omap2xxx_cm_wait_module_ready() fails?
161 	 */
162 	return 0;
163 }
164 
165 /* Stop APLL */
166 static void _omap2xxx_apll_disable(u8 enable_bit)
167 {
168 	u32 v;
169 
170 	v = omap2_cm_read_mod_reg(PLL_MOD, CM_CLKEN);
171 	v &= ~(EN_APLL_LOCKED << enable_bit);
172 	omap2_cm_write_mod_reg(v, PLL_MOD, CM_CLKEN);
173 }
174 
175 /* Enable an APLL if off */
176 int omap2xxx_cm_apll54_enable(void)
177 {
178 	return _omap2xxx_apll_enable(OMAP24XX_EN_54M_PLL_SHIFT,
179 				     OMAP24XX_ST_54M_APLL_SHIFT);
180 }
181 
182 /* Enable an APLL if off */
183 int omap2xxx_cm_apll96_enable(void)
184 {
185 	return _omap2xxx_apll_enable(OMAP24XX_EN_96M_PLL_SHIFT,
186 				     OMAP24XX_ST_96M_APLL_SHIFT);
187 }
188 
189 /* Stop APLL */
190 void omap2xxx_cm_apll54_disable(void)
191 {
192 	_omap2xxx_apll_disable(OMAP24XX_EN_54M_PLL_SHIFT);
193 }
194 
195 /* Stop APLL */
196 void omap2xxx_cm_apll96_disable(void)
197 {
198 	_omap2xxx_apll_disable(OMAP24XX_EN_96M_PLL_SHIFT);
199 }
200 
201 /**
202  * omap2xxx_cm_split_idlest_reg - split CM_IDLEST reg addr into its components
203  * @idlest_reg: CM_IDLEST* virtual address
204  * @prcm_inst: pointer to an s16 to return the PRCM instance offset
205  * @idlest_reg_id: pointer to a u8 to return the CM_IDLESTx register ID
206  *
207  * XXX This function is only needed until absolute register addresses are
208  * removed from the OMAP struct clk records.
209  */
210 int omap2xxx_cm_split_idlest_reg(void __iomem *idlest_reg, s16 *prcm_inst,
211 				 u8 *idlest_reg_id)
212 {
213 	unsigned long offs;
214 	u8 idlest_offs;
215 	int i;
216 
217 	if (idlest_reg < cm_base || idlest_reg > (cm_base + 0x0fff))
218 		return -EINVAL;
219 
220 	idlest_offs = (unsigned long)idlest_reg & 0xff;
221 	for (i = 0; i < ARRAY_SIZE(omap2xxx_cm_idlest_offs); i++) {
222 		if (idlest_offs == omap2xxx_cm_idlest_offs[i]) {
223 			*idlest_reg_id = i + 1;
224 			break;
225 		}
226 	}
227 
228 	if (i == ARRAY_SIZE(omap2xxx_cm_idlest_offs))
229 		return -EINVAL;
230 
231 	offs = idlest_reg - cm_base;
232 	offs &= 0xff00;
233 	*prcm_inst = offs;
234 
235 	return 0;
236 }
237 
238 /*
239  *
240  */
241 
242 /**
243  * omap2xxx_cm_wait_module_ready - wait for a module to leave idle or standby
244  * @prcm_mod: PRCM module offset
245  * @idlest_id: CM_IDLESTx register ID (i.e., x = 1, 2, 3)
246  * @idlest_shift: shift of the bit in the CM_IDLEST* register to check
247  *
248  * Wait for the PRCM to indicate that the module identified by
249  * (@prcm_mod, @idlest_id, @idlest_shift) is clocked.  Return 0 upon
250  * success or -EBUSY if the module doesn't enable in time.
251  */
252 int omap2xxx_cm_wait_module_ready(s16 prcm_mod, u8 idlest_id, u8 idlest_shift)
253 {
254 	int ena = 0, i = 0;
255 	u8 cm_idlest_reg;
256 	u32 mask;
257 
258 	if (!idlest_id || (idlest_id > ARRAY_SIZE(omap2xxx_cm_idlest_offs)))
259 		return -EINVAL;
260 
261 	cm_idlest_reg = omap2xxx_cm_idlest_offs[idlest_id - 1];
262 
263 	mask = 1 << idlest_shift;
264 	ena = mask;
265 
266 	omap_test_timeout(((omap2_cm_read_mod_reg(prcm_mod, cm_idlest_reg) &
267 			    mask) == ena), MAX_MODULE_READY_TIME, i);
268 
269 	return (i < MAX_MODULE_READY_TIME) ? 0 : -EBUSY;
270 }
271 
272 /* Clockdomain low-level functions */
273 
274 static void omap2xxx_clkdm_allow_idle(struct clockdomain *clkdm)
275 {
276 	omap2xxx_cm_clkdm_enable_hwsup(clkdm->pwrdm.ptr->prcm_offs,
277 				       clkdm->clktrctrl_mask);
278 }
279 
280 static void omap2xxx_clkdm_deny_idle(struct clockdomain *clkdm)
281 {
282 	omap2xxx_cm_clkdm_disable_hwsup(clkdm->pwrdm.ptr->prcm_offs,
283 					clkdm->clktrctrl_mask);
284 }
285 
286 static int omap2xxx_clkdm_clk_enable(struct clockdomain *clkdm)
287 {
288 	bool hwsup = false;
289 
290 	if (!clkdm->clktrctrl_mask)
291 		return 0;
292 
293 	hwsup = omap2xxx_cm_is_clkdm_in_hwsup(clkdm->pwrdm.ptr->prcm_offs,
294 					      clkdm->clktrctrl_mask);
295 	if (!hwsup && clkdm->flags & CLKDM_CAN_FORCE_WAKEUP)
296 		omap2xxx_clkdm_wakeup(clkdm);
297 
298 	return 0;
299 }
300 
301 static int omap2xxx_clkdm_clk_disable(struct clockdomain *clkdm)
302 {
303 	bool hwsup = false;
304 
305 	if (!clkdm->clktrctrl_mask)
306 		return 0;
307 
308 	hwsup = omap2xxx_cm_is_clkdm_in_hwsup(clkdm->pwrdm.ptr->prcm_offs,
309 					      clkdm->clktrctrl_mask);
310 
311 	if (!hwsup && clkdm->flags & CLKDM_CAN_FORCE_SLEEP)
312 		omap2xxx_clkdm_sleep(clkdm);
313 
314 	return 0;
315 }
316 
317 struct clkdm_ops omap2_clkdm_operations = {
318 	.clkdm_add_wkdep	= omap2_clkdm_add_wkdep,
319 	.clkdm_del_wkdep	= omap2_clkdm_del_wkdep,
320 	.clkdm_read_wkdep	= omap2_clkdm_read_wkdep,
321 	.clkdm_clear_all_wkdeps	= omap2_clkdm_clear_all_wkdeps,
322 	.clkdm_sleep		= omap2xxx_clkdm_sleep,
323 	.clkdm_wakeup		= omap2xxx_clkdm_wakeup,
324 	.clkdm_allow_idle	= omap2xxx_clkdm_allow_idle,
325 	.clkdm_deny_idle	= omap2xxx_clkdm_deny_idle,
326 	.clkdm_clk_enable	= omap2xxx_clkdm_clk_enable,
327 	.clkdm_clk_disable	= omap2xxx_clkdm_clk_disable,
328 };
329 
330 /*
331  *
332  */
333 
334 static struct cm_ll_data omap2xxx_cm_ll_data = {
335 	.split_idlest_reg	= &omap2xxx_cm_split_idlest_reg,
336 	.wait_module_ready	= &omap2xxx_cm_wait_module_ready,
337 };
338 
339 int __init omap2xxx_cm_init(void)
340 {
341 	if (!cpu_is_omap24xx())
342 		return 0;
343 
344 	return cm_register(&omap2xxx_cm_ll_data);
345 }
346 
347 static void __exit omap2xxx_cm_exit(void)
348 {
349 	if (!cpu_is_omap24xx())
350 		return;
351 
352 	/* Should never happen */
353 	WARN(cm_unregister(&omap2xxx_cm_ll_data),
354 	     "%s: cm_ll_data function pointer mismatch\n", __func__);
355 }
356 __exitcall(omap2xxx_cm_exit);
357