xref: /openbmc/linux/arch/arm/mach-omap2/sr_device.c (revision 275876e2)
1 /*
2  * OMAP3/OMAP4 smartreflex device file
3  *
4  * Author: Thara Gopinath	<thara@ti.com>
5  *
6  * Based originally on code from smartreflex.c
7  * Copyright (C) 2010 Texas Instruments, Inc.
8  * Thara Gopinath <thara@ti.com>
9  *
10  * Copyright (C) 2008 Nokia Corporation
11  * Kalle Jokiniemi
12  *
13  * Copyright (C) 2007 Texas Instruments, Inc.
14  * Lesly A M <x0080970@ti.com>
15  *
16  * This program is free software; you can redistribute it and/or modify
17  * it under the terms of the GNU General Public License version 2 as
18  * published by the Free Software Foundation.
19  */
20 #include <linux/power/smartreflex.h>
21 
22 #include <linux/err.h>
23 #include <linux/slab.h>
24 #include <linux/io.h>
25 
26 #include "soc.h"
27 #include "omap_device.h"
28 #include "voltage.h"
29 #include "control.h"
30 #include "pm.h"
31 
32 static bool sr_enable_on_init;
33 
34 /* Read EFUSE values from control registers for OMAP3430 */
35 static void __init sr_set_nvalues(struct omap_volt_data *volt_data,
36 				struct omap_sr_data *sr_data)
37 {
38 	struct omap_sr_nvalue_table *nvalue_table;
39 	int i, j, count = 0;
40 
41 	sr_data->nvalue_count = 0;
42 	sr_data->nvalue_table = NULL;
43 
44 	while (volt_data[count].volt_nominal)
45 		count++;
46 
47 	nvalue_table = kzalloc(sizeof(struct omap_sr_nvalue_table)*count,
48 			GFP_KERNEL);
49 
50 	if (!nvalue_table) {
51 		pr_err("OMAP: SmartReflex: cannot allocate memory for n-value table\n");
52 		return;
53 	}
54 
55 	for (i = 0, j = 0; i < count; i++) {
56 		u32 v;
57 
58 		/*
59 		 * In OMAP4 the efuse registers are 24 bit aligned.
60 		 * A readl_relaxed will fail for non-32 bit aligned address
61 		 * and hence the 8-bit read and shift.
62 		 */
63 		if (cpu_is_omap44xx()) {
64 			u16 offset = volt_data[i].sr_efuse_offs;
65 
66 			v = omap_ctrl_readb(offset) |
67 				omap_ctrl_readb(offset + 1) << 8 |
68 				omap_ctrl_readb(offset + 2) << 16;
69 		} else {
70 			v = omap_ctrl_readl(volt_data[i].sr_efuse_offs);
71 		}
72 
73 		/*
74 		 * Many OMAP SoCs don't have the eFuse values set.
75 		 * For example, pretty much all OMAP3xxx before
76 		 * ES3.something.
77 		 *
78 		 * XXX There needs to be some way for board files or
79 		 * userspace to add these in.
80 		 */
81 		if (v == 0)
82 			continue;
83 
84 		nvalue_table[j].nvalue = v;
85 		nvalue_table[j].efuse_offs = volt_data[i].sr_efuse_offs;
86 		nvalue_table[j].errminlimit = volt_data[i].sr_errminlimit;
87 		nvalue_table[j].volt_nominal = volt_data[i].volt_nominal;
88 
89 		j++;
90 	}
91 
92 	sr_data->nvalue_table = nvalue_table;
93 	sr_data->nvalue_count = j;
94 }
95 
96 static int __init sr_dev_init(struct omap_hwmod *oh, void *user)
97 {
98 	struct omap_sr_data *sr_data;
99 	struct platform_device *pdev;
100 	struct omap_volt_data *volt_data;
101 	struct omap_smartreflex_dev_attr *sr_dev_attr;
102 	char *name = "smartreflex";
103 	static int i;
104 
105 	sr_data = kzalloc(sizeof(struct omap_sr_data), GFP_KERNEL);
106 	if (!sr_data) {
107 		pr_err("%s: Unable to allocate memory for %s sr_data\n",
108 		       __func__, oh->name);
109 		return -ENOMEM;
110 	}
111 
112 	sr_dev_attr = (struct omap_smartreflex_dev_attr *)oh->dev_attr;
113 	if (!sr_dev_attr || !sr_dev_attr->sensor_voltdm_name) {
114 		pr_err("%s: No voltage domain specified for %s. Cannot initialize\n",
115 		       __func__, oh->name);
116 		goto exit;
117 	}
118 
119 	sr_data->name = oh->name;
120 	sr_data->ip_type = oh->class->rev;
121 	sr_data->senn_mod = 0x1;
122 	sr_data->senp_mod = 0x1;
123 
124 	if (cpu_is_omap34xx() || cpu_is_omap44xx()) {
125 		sr_data->err_weight = OMAP3430_SR_ERRWEIGHT;
126 		sr_data->err_maxlimit = OMAP3430_SR_ERRMAXLIMIT;
127 		sr_data->accum_data = OMAP3430_SR_ACCUMDATA;
128 		if (!(strcmp(sr_data->name, "smartreflex_mpu"))) {
129 			sr_data->senn_avgweight = OMAP3430_SR1_SENNAVGWEIGHT;
130 			sr_data->senp_avgweight = OMAP3430_SR1_SENPAVGWEIGHT;
131 		} else {
132 			sr_data->senn_avgweight = OMAP3430_SR2_SENNAVGWEIGHT;
133 			sr_data->senp_avgweight = OMAP3430_SR2_SENPAVGWEIGHT;
134 		}
135 	}
136 
137 	sr_data->voltdm = voltdm_lookup(sr_dev_attr->sensor_voltdm_name);
138 	if (!sr_data->voltdm) {
139 		pr_err("%s: Unable to get voltage domain pointer for VDD %s\n",
140 			__func__, sr_dev_attr->sensor_voltdm_name);
141 		goto exit;
142 	}
143 
144 	omap_voltage_get_volttable(sr_data->voltdm, &volt_data);
145 	if (!volt_data) {
146 		pr_err("%s: No Voltage table registered for VDD%d\n",
147 		       __func__, i + 1);
148 		goto exit;
149 	}
150 
151 	sr_set_nvalues(volt_data, sr_data);
152 
153 	sr_data->enable_on_init = sr_enable_on_init;
154 
155 	pdev = omap_device_build(name, i, oh, sr_data, sizeof(*sr_data));
156 	if (IS_ERR(pdev))
157 		pr_warning("%s: Could not build omap_device for %s: %s.\n\n",
158 			__func__, name, oh->name);
159 exit:
160 	i++;
161 	kfree(sr_data);
162 	return 0;
163 }
164 
165 /*
166  * API to be called from board files to enable smartreflex
167  * autocompensation at init.
168  */
169 void __init omap_enable_smartreflex_on_init(void)
170 {
171 	sr_enable_on_init = true;
172 }
173 
174 int __init omap_devinit_smartreflex(void)
175 {
176 	return omap_hwmod_for_each_by_class("smartreflex", sr_dev_init, NULL);
177 }
178