xref: /openbmc/u-boot/drivers/spmi/spmi-msm.c (revision cbd2fba1)
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/io.h>
15 #include <spmi/spmi.h>
16 
17 DECLARE_GLOBAL_DATA_PTR;
18 
19 /* PMIC Arbiter configuration registers */
20 #define PMIC_ARB_VERSION		0x0000
21 #define PMIC_ARB_VERSION_V2_MIN		0x20010000
22 
23 #define ARB_CHANNEL_OFFSET(n)		(0x4 * (n))
24 #define SPMI_CH_OFFSET(chnl)		((chnl) * 0x8000)
25 
26 #define SPMI_REG_CMD0			0x0
27 #define SPMI_REG_CONFIG			0x4
28 #define SPMI_REG_STATUS			0x8
29 #define SPMI_REG_WDATA			0x10
30 #define SPMI_REG_RDATA			0x18
31 
32 #define SPMI_CMD_OPCODE_SHIFT		27
33 #define SPMI_CMD_SLAVE_ID_SHIFT		20
34 #define SPMI_CMD_ADDR_SHIFT		12
35 #define SPMI_CMD_ADDR_OFFSET_SHIFT	4
36 #define SPMI_CMD_BYTE_CNT_SHIFT		0
37 
38 #define SPMI_CMD_EXT_REG_WRITE_LONG	0x00
39 #define SPMI_CMD_EXT_REG_READ_LONG	0x01
40 
41 #define SPMI_STATUS_DONE		0x1
42 
43 #define SPMI_MAX_CHANNELS	128
44 #define SPMI_MAX_SLAVES		16
45 #define SPMI_MAX_PERIPH		256
46 
47 struct msm_spmi_priv {
48 	phys_addr_t arb_chnl; /* ARB channel mapping base */
49 	phys_addr_t spmi_core; /* SPMI core */
50 	phys_addr_t spmi_obs; /* SPMI observer */
51 	/* SPMI channel map */
52 	uint8_t channel_map[SPMI_MAX_SLAVES][SPMI_MAX_PERIPH];
53 };
54 
55 static int msm_spmi_write(struct udevice *dev, int usid, int pid, int off,
56 			  uint8_t val)
57 {
58 	struct msm_spmi_priv *priv = dev_get_priv(dev);
59 	unsigned channel;
60 	uint32_t reg = 0;
61 
62 	if (usid >= SPMI_MAX_SLAVES)
63 		return -EIO;
64 	if (pid >= SPMI_MAX_PERIPH)
65 		return -EIO;
66 
67 	channel = priv->channel_map[usid][pid];
68 
69 	/* Disable IRQ mode for the current channel*/
70 	writel(0x0, priv->spmi_core + SPMI_CH_OFFSET(channel) +
71 	       SPMI_REG_CONFIG);
72 
73 	/* Write single byte */
74 	writel(val, priv->spmi_core + SPMI_CH_OFFSET(channel) + SPMI_REG_WDATA);
75 
76 	/* Prepare write command */
77 	reg |= SPMI_CMD_EXT_REG_WRITE_LONG << SPMI_CMD_OPCODE_SHIFT;
78 	reg |= (usid << SPMI_CMD_SLAVE_ID_SHIFT);
79 	reg |= (pid << SPMI_CMD_ADDR_SHIFT);
80 	reg |= (off << SPMI_CMD_ADDR_OFFSET_SHIFT);
81 	reg |= 1; /* byte count */
82 
83 	/* Send write command */
84 	writel(reg, priv->spmi_core + SPMI_CH_OFFSET(channel) + SPMI_REG_CMD0);
85 
86 	/* Wait till CMD DONE status */
87 	reg = 0;
88 	while (!reg) {
89 		reg = readl(priv->spmi_core + SPMI_CH_OFFSET(channel) +
90 			    SPMI_REG_STATUS);
91 	}
92 
93 	if (reg ^ SPMI_STATUS_DONE) {
94 		printf("SPMI write failure.\n");
95 		return -EIO;
96 	}
97 
98 	return 0;
99 }
100 
101 static int msm_spmi_read(struct udevice *dev, int usid, int pid, int off)
102 {
103 	struct msm_spmi_priv *priv = dev_get_priv(dev);
104 	unsigned channel;
105 	uint32_t reg = 0;
106 
107 	if (usid >= SPMI_MAX_SLAVES)
108 		return -EIO;
109 	if (pid >= SPMI_MAX_PERIPH)
110 		return -EIO;
111 
112 	channel = priv->channel_map[usid][pid];
113 
114 	/* Disable IRQ mode for the current channel*/
115 	writel(0x0, priv->spmi_obs + SPMI_CH_OFFSET(channel) + SPMI_REG_CONFIG);
116 
117 	/* Prepare read command */
118 	reg |= SPMI_CMD_EXT_REG_READ_LONG << SPMI_CMD_OPCODE_SHIFT;
119 	reg |= (usid << SPMI_CMD_SLAVE_ID_SHIFT);
120 	reg |= (pid << SPMI_CMD_ADDR_SHIFT);
121 	reg |= (off << SPMI_CMD_ADDR_OFFSET_SHIFT);
122 	reg |= 1; /* byte count */
123 
124 	/* Request read */
125 	writel(reg, priv->spmi_obs + SPMI_CH_OFFSET(channel) + SPMI_REG_CMD0);
126 
127 	/* Wait till CMD DONE status */
128 	reg = 0;
129 	while (!reg) {
130 		reg = readl(priv->spmi_obs + SPMI_CH_OFFSET(channel) +
131 			    SPMI_REG_STATUS);
132 	}
133 
134 	if (reg ^ SPMI_STATUS_DONE) {
135 		printf("SPMI read failure.\n");
136 		return -EIO;
137 	}
138 
139 	/* Read the data */
140 	return readl(priv->spmi_obs + SPMI_CH_OFFSET(channel) +
141 		     SPMI_REG_RDATA) & 0xFF;
142 }
143 
144 static struct dm_spmi_ops msm_spmi_ops = {
145 	.read = msm_spmi_read,
146 	.write = msm_spmi_write,
147 };
148 
149 static int msm_spmi_probe(struct udevice *dev)
150 {
151 	struct udevice *parent = dev->parent;
152 	struct msm_spmi_priv *priv = dev_get_priv(dev);
153 	int node = dev_of_offset(dev);
154 	u32 hw_ver;
155 	bool is_v1;
156 	int i;
157 
158 	priv->arb_chnl = devfdt_get_addr(dev);
159 	priv->spmi_core = fdtdec_get_addr_size_auto_parent(gd->fdt_blob,
160 			dev_of_offset(parent), node, "reg", 1, NULL, false);
161 	priv->spmi_obs = fdtdec_get_addr_size_auto_parent(gd->fdt_blob,
162 			dev_of_offset(parent), node, "reg", 2, NULL, false);
163 
164 	hw_ver = readl(priv->arb_chnl + PMIC_ARB_VERSION - 0x800);
165 	is_v1  = (hw_ver < PMIC_ARB_VERSION_V2_MIN);
166 
167 	dev_dbg(dev, "PMIC Arb Version-%d (0x%x)\n", (is_v1 ? 1 : 2), hw_ver);
168 
169 	if (priv->arb_chnl == FDT_ADDR_T_NONE ||
170 	    priv->spmi_core == FDT_ADDR_T_NONE ||
171 	    priv->spmi_obs == FDT_ADDR_T_NONE)
172 		return -EINVAL;
173 
174 	/* Scan peripherals connected to each SPMI channel */
175 	for (i = 0; i < SPMI_MAX_PERIPH ; i++) {
176 		uint32_t periph = readl(priv->arb_chnl + ARB_CHANNEL_OFFSET(i));
177 		uint8_t slave_id = (periph & 0xf0000) >> 16;
178 		uint8_t pid = (periph & 0xff00) >> 8;
179 
180 		priv->channel_map[slave_id][pid] = i;
181 	}
182 	return 0;
183 }
184 
185 static const struct udevice_id msm_spmi_ids[] = {
186 	{ .compatible = "qcom,spmi-pmic-arb" },
187 	{ }
188 };
189 
190 U_BOOT_DRIVER(msm_spmi) = {
191 	.name = "msm_spmi",
192 	.id = UCLASS_SPMI,
193 	.of_match = msm_spmi_ids,
194 	.ops = &msm_spmi_ops,
195 	.probe = msm_spmi_probe,
196 	.priv_auto_alloc_size = sizeof(struct msm_spmi_priv),
197 };
198