1 // SPDX-License-Identifier: BSD-3-Clause
2 /*
3  * Qualcomm SPMI bus driver
4  *
5  * (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com>
6  *
7  * Loosely based on Little Kernel driver
8  */
9 
10 #include <common.h>
11 #include <dm.h>
12 #include <errno.h>
13 #include <fdtdec.h>
14 #include <asm/global_data.h>
15 #include <asm/io.h>
16 #include <dm/device_compat.h>
17 #include <spmi/spmi.h>
18 
19 DECLARE_GLOBAL_DATA_PTR;
20 
21 /* PMIC Arbiter configuration registers */
22 #define PMIC_ARB_VERSION 0x0000
23 #define PMIC_ARB_VERSION_V2_MIN 0x20010000
24 #define PMIC_ARB_VERSION_V3_MIN 0x30000000
25 #define PMIC_ARB_VERSION_V5_MIN 0x50000000
26 
27 #define APID_MAP_OFFSET_V1_V2_V3 (0x800)
28 #define APID_MAP_OFFSET_V5 (0x900)
29 #define ARB_CHANNEL_OFFSET(n) (0x4 * (n))
30 #define SPMI_CH_OFFSET(chnl) ((chnl) * 0x8000)
31 #define SPMI_V5_OBS_CH_OFFSET(chnl) ((chnl) * 0x80)
32 #define SPMI_V5_RW_CH_OFFSET(chnl) ((chnl) * 0x10000)
33 
34 #define SPMI_REG_CMD0 0x0
35 #define SPMI_REG_CONFIG 0x4
36 #define SPMI_REG_STATUS 0x8
37 #define SPMI_REG_WDATA 0x10
38 #define SPMI_REG_RDATA 0x18
39 
40 #define SPMI_CMD_OPCODE_SHIFT 27
41 #define SPMI_CMD_SLAVE_ID_SHIFT 20
42 #define SPMI_CMD_ADDR_SHIFT 12
43 #define SPMI_CMD_ADDR_OFFSET_SHIFT 4
44 #define SPMI_CMD_BYTE_CNT_SHIFT 0
45 
46 #define SPMI_CMD_EXT_REG_WRITE_LONG 0x00
47 #define SPMI_CMD_EXT_REG_READ_LONG 0x01
48 
49 #define SPMI_STATUS_DONE 0x1
50 
51 #define SPMI_MAX_CHANNELS 128
52 #define SPMI_MAX_SLAVES 16
53 #define SPMI_MAX_PERIPH 256
54 
55 enum arb_ver {
56 	V1 = 1,
57 	V2,
58 	V3,
59 	V5 = 5
60 };
61 
62 /*
63  * PMIC arbiter version 5 uses different register offsets for read/write vs
64  * observer channels.
65  */
66 enum pmic_arb_channel {
67 	PMIC_ARB_CHANNEL_RW,
68 	PMIC_ARB_CHANNEL_OBS,
69 };
70 
71 struct msm_spmi_priv {
72 	phys_addr_t arb_chnl;  /* ARB channel mapping base */
73 	phys_addr_t spmi_core; /* SPMI core */
74 	phys_addr_t spmi_obs;  /* SPMI observer */
75 	/* SPMI channel map */
76 	uint8_t channel_map[SPMI_MAX_SLAVES][SPMI_MAX_PERIPH];
77 	/* SPMI bus arbiter version */
78 	u32 arb_ver;
79 };
80 
msm_spmi_write(struct udevice * dev,int usid,int pid,int off,uint8_t val)81 static int msm_spmi_write(struct udevice *dev, int usid, int pid, int off,
82 			  uint8_t val)
83 {
84 	struct msm_spmi_priv *priv = dev_get_priv(dev);
85 	unsigned channel;
86 	unsigned int ch_offset;
87 	uint32_t reg = 0;
88 
89 	if (usid >= SPMI_MAX_SLAVES)
90 		return -EIO;
91 	if (pid >= SPMI_MAX_PERIPH)
92 		return -EIO;
93 
94 	channel = priv->channel_map[usid][pid];
95 
96 	/* Disable IRQ mode for the current channel*/
97 	writel(0x0,
98 	       priv->spmi_core + SPMI_CH_OFFSET(channel) + SPMI_REG_CONFIG);
99 
100 	/* Write single byte */
101 	writel(val, priv->spmi_core + SPMI_CH_OFFSET(channel) + SPMI_REG_WDATA);
102 
103 	/* Prepare write command */
104 	reg |= SPMI_CMD_EXT_REG_WRITE_LONG << SPMI_CMD_OPCODE_SHIFT;
105 	reg |= (usid << SPMI_CMD_SLAVE_ID_SHIFT);
106 	reg |= (pid << SPMI_CMD_ADDR_SHIFT);
107 	reg |= (off << SPMI_CMD_ADDR_OFFSET_SHIFT);
108 	reg |= 1; /* byte count */
109 
110 	if (priv->arb_ver == V5)
111 		ch_offset = SPMI_V5_RW_CH_OFFSET(channel);
112 	else
113 		ch_offset = SPMI_CH_OFFSET(channel);
114 
115 	/* Send write command */
116 	writel(reg, priv->spmi_core + SPMI_CH_OFFSET(channel) + SPMI_REG_CMD0);
117 
118 	/* Wait till CMD DONE status */
119 	reg = 0;
120 	while (!reg) {
121 		reg = readl(priv->spmi_core + SPMI_CH_OFFSET(channel) +
122 			    SPMI_REG_STATUS);
123 	}
124 
125 	if (reg ^ SPMI_STATUS_DONE) {
126 		printf("SPMI write failure.\n");
127 		return -EIO;
128 	}
129 
130 	return 0;
131 }
132 
msm_spmi_read(struct udevice * dev,int usid,int pid,int off)133 static int msm_spmi_read(struct udevice *dev, int usid, int pid, int off)
134 {
135 	struct msm_spmi_priv *priv = dev_get_priv(dev);
136 	unsigned channel;
137 	unsigned int ch_offset;
138 	uint32_t reg = 0;
139 
140 	if (usid >= SPMI_MAX_SLAVES)
141 		return -EIO;
142 	if (pid >= SPMI_MAX_PERIPH)
143 		return -EIO;
144 
145 	channel = priv->channel_map[usid][pid];
146 
147 	if (priv->arb_ver == V5)
148 		ch_offset = SPMI_V5_OBS_CH_OFFSET(channel);
149 	else
150 		ch_offset = SPMI_CH_OFFSET(channel);
151 
152 	/* Disable IRQ mode for the current channel*/
153 	writel(0x0, priv->spmi_obs + ch_offset + SPMI_REG_CONFIG);
154 
155 	/* Prepare read command */
156 	reg |= SPMI_CMD_EXT_REG_READ_LONG << SPMI_CMD_OPCODE_SHIFT;
157 	reg |= (usid << SPMI_CMD_SLAVE_ID_SHIFT);
158 	reg |= (pid << SPMI_CMD_ADDR_SHIFT);
159 	reg |= (off << SPMI_CMD_ADDR_OFFSET_SHIFT);
160 	reg |= 1; /* byte count */
161 
162 	/* Request read */
163 	writel(reg, priv->spmi_obs + ch_offset + SPMI_REG_CMD0);
164 
165 	/* Wait till CMD DONE status */
166 	reg = 0;
167 	while (!reg) {
168 		reg = readl(priv->spmi_obs + ch_offset + SPMI_REG_STATUS);
169 	}
170 
171 	if (reg ^ SPMI_STATUS_DONE) {
172 		printf("SPMI read failure.\n");
173 		return -EIO;
174 	}
175 
176 	/* Read the data */
177 	return readl(priv->spmi_obs + ch_offset +
178 				SPMI_REG_RDATA) & 0xFF;
179 }
180 
181 static struct dm_spmi_ops msm_spmi_ops = {
182 	.read = msm_spmi_read,
183 	.write = msm_spmi_write,
184 };
185 
msm_spmi_probe(struct udevice * dev)186 static int msm_spmi_probe(struct udevice *dev)
187 {
188 	struct msm_spmi_priv *priv = dev_get_priv(dev);
189 	phys_addr_t config_addr;
190 	u32 hw_ver;
191 	u32 version;
192 	int i;
193 	int err;
194 
195 	config_addr = dev_read_addr_index(dev, 0);
196 	priv->spmi_core = dev_read_addr_index(dev, 1);
197 	priv->spmi_obs = dev_read_addr_index(dev, 2);
198 
199 	hw_ver = readl(config_addr + PMIC_ARB_VERSION);
200 
201 	if (hw_ver < PMIC_ARB_VERSION_V3_MIN) {
202 		priv->arb_ver = V2;
203 		version = 2;
204 		priv->arb_chnl = config_addr + APID_MAP_OFFSET_V1_V2_V3;
205 	} else if (hw_ver < PMIC_ARB_VERSION_V5_MIN) {
206 		priv->arb_ver = V3;
207 		version = 3;
208 		priv->arb_chnl = config_addr + APID_MAP_OFFSET_V1_V2_V3;
209 	} else {
210 		priv->arb_ver = V5;
211 		version = 5;
212 		priv->arb_chnl = config_addr + APID_MAP_OFFSET_V5;
213 
214 		if (err) {
215 			dev_err(dev, "could not read APID->PPID mapping table, rc= %d\n", err);
216 			return -1;
217 		}
218 	}
219 
220 	dev_dbg(dev, "PMIC Arb Version-%d (0x%x)\n", version, hw_ver);
221 
222 	if (priv->arb_chnl == FDT_ADDR_T_NONE ||
223 	    priv->spmi_core == FDT_ADDR_T_NONE ||
224 	    priv->spmi_obs == FDT_ADDR_T_NONE)
225 		return -EINVAL;
226 
227 	dev_dbg(dev, "priv->arb_chnl address (%llu)\n", priv->arb_chnl);
228 	dev_dbg(dev, "priv->spmi_core address (%llu)\n", priv->spmi_core);
229 	dev_dbg(dev, "priv->spmi_obs address (%llu)\n", priv->spmi_obs);
230 	/* Scan peripherals connected to each SPMI channel */
231 	for (i = 0; i < SPMI_MAX_PERIPH; i++) {
232 		uint32_t periph = readl(priv->arb_chnl + ARB_CHANNEL_OFFSET(i));
233 		uint8_t slave_id = (periph & 0xf0000) >> 16;
234 		uint8_t pid = (periph & 0xff00) >> 8;
235 
236 		priv->channel_map[slave_id][pid] = i;
237 	}
238 	return 0;
239 }
240 
241 static const struct udevice_id msm_spmi_ids[] = {
242 	{ .compatible = "qcom,spmi-pmic-arb" },
243 	{ }
244 };
245 
246 U_BOOT_DRIVER(msm_spmi) = {
247 	.name = "msm_spmi",
248 	.id = UCLASS_SPMI,
249 	.of_match = msm_spmi_ids,
250 	.ops = &msm_spmi_ops,
251 	.probe = msm_spmi_probe,
252 	.priv_auto = sizeof(struct msm_spmi_priv),
253 };
254