xref: /openbmc/linux/arch/arm/mach-omap2/sr_device.c (revision 82e6fdd6)
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 = kcalloc(count, sizeof(*nvalue_table), GFP_KERNEL);
48 	if (!nvalue_table)
49 		return;
50 
51 	for (i = 0, j = 0; i < count; i++) {
52 		u32 v;
53 
54 		/*
55 		 * In OMAP4 the efuse registers are 24 bit aligned.
56 		 * A readl_relaxed will fail for non-32 bit aligned address
57 		 * and hence the 8-bit read and shift.
58 		 */
59 		if (cpu_is_omap44xx()) {
60 			u16 offset = volt_data[i].sr_efuse_offs;
61 
62 			v = omap_ctrl_readb(offset) |
63 				omap_ctrl_readb(offset + 1) << 8 |
64 				omap_ctrl_readb(offset + 2) << 16;
65 		} else {
66 			v = omap_ctrl_readl(volt_data[i].sr_efuse_offs);
67 		}
68 
69 		/*
70 		 * Many OMAP SoCs don't have the eFuse values set.
71 		 * For example, pretty much all OMAP3xxx before
72 		 * ES3.something.
73 		 *
74 		 * XXX There needs to be some way for board files or
75 		 * userspace to add these in.
76 		 */
77 		if (v == 0)
78 			continue;
79 
80 		nvalue_table[j].nvalue = v;
81 		nvalue_table[j].efuse_offs = volt_data[i].sr_efuse_offs;
82 		nvalue_table[j].errminlimit = volt_data[i].sr_errminlimit;
83 		nvalue_table[j].volt_nominal = volt_data[i].volt_nominal;
84 
85 		j++;
86 	}
87 
88 	sr_data->nvalue_table = nvalue_table;
89 	sr_data->nvalue_count = j;
90 }
91 
92 static int __init sr_dev_init(struct omap_hwmod *oh, void *user)
93 {
94 	struct omap_sr_data *sr_data;
95 	struct platform_device *pdev;
96 	struct omap_volt_data *volt_data;
97 	struct omap_smartreflex_dev_attr *sr_dev_attr;
98 	char *name = "smartreflex";
99 	static int i;
100 
101 	sr_data = kzalloc(sizeof(*sr_data), GFP_KERNEL);
102 	if (!sr_data)
103 		return -ENOMEM;
104 
105 	sr_dev_attr = (struct omap_smartreflex_dev_attr *)oh->dev_attr;
106 	if (!sr_dev_attr || !sr_dev_attr->sensor_voltdm_name) {
107 		pr_err("%s: No voltage domain specified for %s. Cannot initialize\n",
108 		       __func__, oh->name);
109 		goto exit;
110 	}
111 
112 	sr_data->name = oh->name;
113 	sr_data->ip_type = oh->class->rev;
114 	sr_data->senn_mod = 0x1;
115 	sr_data->senp_mod = 0x1;
116 
117 	if (cpu_is_omap34xx() || cpu_is_omap44xx()) {
118 		sr_data->err_weight = OMAP3430_SR_ERRWEIGHT;
119 		sr_data->err_maxlimit = OMAP3430_SR_ERRMAXLIMIT;
120 		sr_data->accum_data = OMAP3430_SR_ACCUMDATA;
121 		if (!(strcmp(sr_data->name, "smartreflex_mpu"))) {
122 			sr_data->senn_avgweight = OMAP3430_SR1_SENNAVGWEIGHT;
123 			sr_data->senp_avgweight = OMAP3430_SR1_SENPAVGWEIGHT;
124 		} else {
125 			sr_data->senn_avgweight = OMAP3430_SR2_SENNAVGWEIGHT;
126 			sr_data->senp_avgweight = OMAP3430_SR2_SENPAVGWEIGHT;
127 		}
128 	}
129 
130 	sr_data->voltdm = voltdm_lookup(sr_dev_attr->sensor_voltdm_name);
131 	if (!sr_data->voltdm) {
132 		pr_err("%s: Unable to get voltage domain pointer for VDD %s\n",
133 			__func__, sr_dev_attr->sensor_voltdm_name);
134 		goto exit;
135 	}
136 
137 	omap_voltage_get_volttable(sr_data->voltdm, &volt_data);
138 	if (!volt_data) {
139 		pr_err("%s: No Voltage table registered for VDD%d\n",
140 		       __func__, i + 1);
141 		goto exit;
142 	}
143 
144 	sr_set_nvalues(volt_data, sr_data);
145 
146 	sr_data->enable_on_init = sr_enable_on_init;
147 
148 	pdev = omap_device_build(name, i, oh, sr_data, sizeof(*sr_data));
149 	if (IS_ERR(pdev))
150 		pr_warn("%s: Could not build omap_device for %s: %s\n",
151 			__func__, name, oh->name);
152 exit:
153 	i++;
154 	kfree(sr_data);
155 	return 0;
156 }
157 
158 /*
159  * API to be called from board files to enable smartreflex
160  * autocompensation at init.
161  */
162 void __init omap_enable_smartreflex_on_init(void)
163 {
164 	sr_enable_on_init = true;
165 }
166 
167 int __init omap_devinit_smartreflex(void)
168 {
169 	return omap_hwmod_for_each_by_class("smartreflex", sr_dev_init, NULL);
170 }
171