1 // SPDX-License-Identifier: (GPL-2.0 OR MIT)
2 /*
3  * Microsemi SoCs serial gpio driver
4  *
5  * Author: <lars.povlsen@microchip.com>
6  *
7  * Copyright (c) 2018 Microsemi Corporation
8  */
9 
10 #include <common.h>
11 #include <dm.h>
12 #include <log.h>
13 #include <asm/gpio.h>
14 #include <asm/io.h>
15 #include <errno.h>
16 #include <clk.h>
17 #include <dm/device_compat.h>
18 #include <linux/bitops.h>
19 #include <linux/err.h>
20 
21 #define MSCC_SGPIOS_PER_BANK	32
22 #define MSCC_SGPIO_BANK_DEPTH	4
23 
24 enum {
25 	REG_INPUT_DATA,
26 	REG_PORT_CONFIG,
27 	REG_PORT_ENABLE,
28 	REG_SIO_CONFIG,
29 	REG_SIO_CLOCK,
30 	MAXREG
31 };
32 
33 struct mscc_sgpio_bf {
34 	u8 beg;
35 	u8 end;
36 };
37 
38 struct mscc_sgpio_props {
39 	u8 regoff[MAXREG];
40 	struct mscc_sgpio_bf auto_repeat;
41 	struct mscc_sgpio_bf port_width;
42 	struct mscc_sgpio_bf clk_freq;
43 	struct mscc_sgpio_bf bit_source;
44 };
45 
46 #define __M(bf)		GENMASK((bf).end, (bf).beg)
47 #define __F(bf, x)	(__M(bf) & ((x) << (bf).beg))
48 #define __X(bf, x)	(((x) >> (bf).beg) & GENMASK(((bf).end - (bf).beg), 0))
49 
50 #define MSCC_M_CFG_SIO_AUTO_REPEAT(p)		BIT(p->props->auto_repeat.beg)
51 #define MSCC_F_CFG_SIO_PORT_WIDTH(p, x)		__F(p->props->port_width, x)
52 #define MSCC_M_CFG_SIO_PORT_WIDTH(p)		__M(p->props->port_width)
53 #define MSCC_F_CLOCK_SIO_CLK_FREQ(p, x)		__F(p->props->clk_freq, x)
54 #define MSCC_M_CLOCK_SIO_CLK_FREQ(p)		__M(p->props->clk_freq)
55 #define MSCC_F_PORT_CFG_BIT_SOURCE(p, x)	__F(p->props->bit_source, x)
56 #define MSCC_X_PORT_CFG_BIT_SOURCE(p, x)	__X(p->props->bit_source, x)
57 
58 const struct mscc_sgpio_props props_luton = {
59 	.regoff = { 0x00, 0x09, 0x29, 0x2a, 0x2b },
60 	.auto_repeat = { 5, 5 },
61 	.port_width  = { 2, 3 },
62 	.clk_freq    = { 0, 11 },
63 	.bit_source  = { 0, 11 },
64 };
65 
66 const struct mscc_sgpio_props props_ocelot = {
67 	.regoff = { 0x00, 0x06, 0x26, 0x04, 0x05 },
68 	.auto_repeat = { 10, 10 },
69 	.port_width  = {  7, 8  },
70 	.clk_freq    = {  8, 19 },
71 	.bit_source  = { 12, 23 },
72 };
73 
74 struct mscc_sgpio_priv {
75 	u32 bitcount;
76 	u32 ports;
77 	u32 clock;
78 	u32 mode[MSCC_SGPIOS_PER_BANK];
79 	u32 __iomem *regs;
80 	const struct mscc_sgpio_props *props;
81 };
82 
sgpio_readl(struct mscc_sgpio_priv * priv,u32 rno,u32 off)83 static inline u32 sgpio_readl(struct mscc_sgpio_priv *priv, u32 rno, u32 off)
84 {
85 	u32 __iomem *reg = &priv->regs[priv->props->regoff[rno] + off];
86 
87 	return readl(reg);
88 }
89 
sgpio_writel(struct mscc_sgpio_priv * priv,u32 val,u32 rno,u32 off)90 static inline void sgpio_writel(struct mscc_sgpio_priv *priv,
91 				u32 val, u32 rno, u32 off)
92 {
93 	u32 __iomem *reg = &priv->regs[priv->props->regoff[rno] + off];
94 
95 	writel(val, reg);
96 }
97 
sgpio_clrsetbits(struct mscc_sgpio_priv * priv,u32 rno,u32 off,u32 clear,u32 set)98 static void sgpio_clrsetbits(struct mscc_sgpio_priv *priv,
99 			     u32 rno, u32 off, u32 clear, u32 set)
100 {
101 	u32 __iomem *reg = &priv->regs[priv->props->regoff[rno] + off];
102 
103 	clrsetbits_le32(reg, clear, set);
104 }
105 
mscc_sgpio_direction_input(struct udevice * dev,unsigned int gpio)106 static int mscc_sgpio_direction_input(struct udevice *dev, unsigned int gpio)
107 {
108 	struct mscc_sgpio_priv *priv = dev_get_priv(dev);
109 
110 	u32 port = gpio % MSCC_SGPIOS_PER_BANK;
111 	u32 bit = gpio / MSCC_SGPIOS_PER_BANK;
112 
113 	priv->mode[port] |= BIT(bit);
114 
115 	return 0;
116 }
117 
mscc_sgpio_direction_output(struct udevice * dev,unsigned int gpio,int value)118 static int mscc_sgpio_direction_output(struct udevice *dev,
119 				       unsigned int gpio, int value)
120 {
121 	struct mscc_sgpio_priv *priv = dev_get_priv(dev);
122 	u32 port = gpio % MSCC_SGPIOS_PER_BANK;
123 	u32 bit = gpio / MSCC_SGPIOS_PER_BANK;
124 	u32 mask = 3 << (3 * bit);
125 
126 	debug("set: port %d, bit %d, mask 0x%08x, value %d\n",
127 	      port, bit, mask, value);
128 
129 	value = (value & 3) << (3 * bit);
130 	sgpio_clrsetbits(priv, REG_PORT_CONFIG, port,
131 			 MSCC_F_PORT_CFG_BIT_SOURCE(priv, mask),
132 			 MSCC_F_PORT_CFG_BIT_SOURCE(priv, value));
133 	clrbits_le32(&priv->mode[port], BIT(bit));
134 
135 	return 0;
136 }
137 
mscc_sgpio_get_function(struct udevice * dev,unsigned int gpio)138 static int mscc_sgpio_get_function(struct udevice *dev, unsigned int gpio)
139 {
140 	struct mscc_sgpio_priv *priv = dev_get_priv(dev);
141 	u32 port = gpio % MSCC_SGPIOS_PER_BANK;
142 	u32 bit = gpio / MSCC_SGPIOS_PER_BANK;
143 	u32 val = priv->mode[port] & BIT(bit);
144 
145 	if (val)
146 		return GPIOF_INPUT;
147 	else
148 		return GPIOF_OUTPUT;
149 }
150 
mscc_sgpio_set_value(struct udevice * dev,unsigned int gpio,int value)151 static int mscc_sgpio_set_value(struct udevice *dev,
152 				unsigned int gpio, int value)
153 {
154 	return mscc_sgpio_direction_output(dev, gpio, value);
155 }
156 
mscc_sgpio_get_value(struct udevice * dev,unsigned int gpio)157 static int mscc_sgpio_get_value(struct udevice *dev, unsigned int gpio)
158 {
159 	struct mscc_sgpio_priv *priv = dev_get_priv(dev);
160 	u32 port = gpio % MSCC_SGPIOS_PER_BANK;
161 	u32 bit = gpio / MSCC_SGPIOS_PER_BANK;
162 	int ret;
163 
164 	if (mscc_sgpio_get_function(dev, gpio) == GPIOF_INPUT) {
165 		ret = !!(sgpio_readl(priv, REG_INPUT_DATA, bit) & BIT(port));
166 	} else {
167 		u32 portval = sgpio_readl(priv, REG_PORT_CONFIG, port);
168 
169 		ret = MSCC_X_PORT_CFG_BIT_SOURCE(priv, portval);
170 		ret = !!(ret & (3 << (3 * bit)));
171 	}
172 
173 	debug("get: gpio %d, port %d, bit %d, value %d\n",
174 	      gpio, port, bit, ret);
175 	return ret;
176 }
177 
mscc_sgpio_get_count(struct udevice * dev)178 static int mscc_sgpio_get_count(struct udevice *dev)
179 {
180 	struct ofnode_phandle_args args;
181 	int count = 0, i = 0, ret;
182 
183 	ret = dev_read_phandle_with_args(dev, "gpio-ranges", NULL, 3, i, &args);
184 	while (ret != -ENOENT) {
185 		count += args.args[2];
186 		ret = dev_read_phandle_with_args(dev, "gpio-ranges", NULL, 3,
187 						 ++i, &args);
188 	}
189 	return count;
190 }
191 
mscc_sgpio_probe(struct udevice * dev)192 static int mscc_sgpio_probe(struct udevice *dev)
193 {
194 	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
195 	struct mscc_sgpio_priv *priv = dev_get_priv(dev);
196 	int err, div_clock = 0, port;
197 	u32 val;
198 	struct clk clk;
199 
200 	err = clk_get_by_index(dev, 0, &clk);
201 	if (!err) {
202 		err = clk_get_rate(&clk);
203 		if (IS_ERR_VALUE(err)) {
204 			dev_err(dev, "Invalid clk rate\n");
205 			return -EINVAL;
206 		}
207 		div_clock = err;
208 	} else {
209 		dev_err(dev, "Failed to get clock\n");
210 		return err;
211 	}
212 
213 	priv->props = (const struct mscc_sgpio_props *)dev_get_driver_data(dev);
214 	priv->ports = dev_read_u32_default(dev, "mscc,sgpio-ports", 0xFFFFFFFF);
215 	priv->clock = dev_read_u32_default(dev, "mscc,sgpio-frequency",
216 					   12500000);
217 	if (priv->clock <= 0 || priv->clock > div_clock) {
218 		dev_err(dev, "Invalid frequency %d\n", priv->clock);
219 		return -EINVAL;
220 	}
221 
222 	uc_priv->gpio_count = mscc_sgpio_get_count(dev);
223 	uc_priv->gpio_count = dev_read_u32_default(dev, "ngpios",
224 						   uc_priv->gpio_count);
225 	if (uc_priv->gpio_count < 1 || uc_priv->gpio_count >
226 	    (4 * MSCC_SGPIOS_PER_BANK)) {
227 		dev_err(dev, "Invalid gpio count %d\n", uc_priv->gpio_count);
228 		return -EINVAL;
229 	}
230 	priv->bitcount = DIV_ROUND_UP(uc_priv->gpio_count,
231 				      MSCC_SGPIOS_PER_BANK);
232 	debug("probe: gpios = %d, bit-count = %d\n",
233 	      uc_priv->gpio_count, priv->bitcount);
234 
235 	priv->regs = (u32 __iomem *)dev_read_addr(dev);
236 	uc_priv->bank_name = "sgpio";
237 
238 	sgpio_clrsetbits(priv, REG_SIO_CONFIG, 0,
239 			 MSCC_M_CFG_SIO_PORT_WIDTH(priv),
240 			 MSCC_F_CFG_SIO_PORT_WIDTH(priv, priv->bitcount - 1) |
241 			 MSCC_M_CFG_SIO_AUTO_REPEAT(priv));
242 	val = div_clock / priv->clock;
243 	debug("probe: div-clock = %d KHz, freq = %d KHz, div = %d\n",
244 	      div_clock / 1000, priv->clock / 1000, val);
245 	sgpio_clrsetbits(priv, REG_SIO_CLOCK, 0,
246 			 MSCC_M_CLOCK_SIO_CLK_FREQ(priv),
247 			 MSCC_F_CLOCK_SIO_CLK_FREQ(priv, val));
248 
249 	for (port = 0; port < 32; port++)
250 		sgpio_writel(priv, 0, REG_PORT_CONFIG, port);
251 	sgpio_writel(priv, priv->ports, REG_PORT_ENABLE, 0);
252 
253 	debug("probe: sgpio regs = %p\n", priv->regs);
254 
255 	return 0;
256 }
257 
258 static const struct dm_gpio_ops mscc_sgpio_ops = {
259 	.direction_input	= mscc_sgpio_direction_input,
260 	.direction_output	= mscc_sgpio_direction_output,
261 	.get_function		= mscc_sgpio_get_function,
262 	.get_value		= mscc_sgpio_get_value,
263 	.set_value		= mscc_sgpio_set_value,
264 };
265 
266 static const struct udevice_id mscc_sgpio_ids[] = {
267 	{ .compatible = "mscc,luton-sgpio", .data = (ulong)&props_luton },
268 	{ .compatible = "mscc,ocelot-sgpio", .data = (ulong)&props_ocelot },
269 	{ }
270 };
271 
272 U_BOOT_DRIVER(gpio_mscc_sgpio) = {
273 	.name			= "mscc-sgpio",
274 	.id			= UCLASS_GPIO,
275 	.of_match		= mscc_sgpio_ids,
276 	.ops			= &mscc_sgpio_ops,
277 	.probe			= mscc_sgpio_probe,
278 	.priv_auto	= sizeof(struct mscc_sgpio_priv),
279 };
280