xref: /openbmc/u-boot/drivers/serial/serial_omap.c (revision 4c0411eb)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Texas Instruments' OMAP serial driver
4  *
5  * Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/
6  *	Lokesh Vutla <lokeshvutla@ti.com>
7  */
8 
9 #include <common.h>
10 #include <dm.h>
11 #include <dt-structs.h>
12 #include <ns16550.h>
13 #include <serial.h>
14 #include <clk.h>
15 
16 #ifndef CONFIG_SYS_NS16550_CLK
17 #define CONFIG_SYS_NS16550_CLK  0
18 #endif
19 
20 #ifdef CONFIG_DEBUG_UART_OMAP
21 
22 #ifndef CONFIG_SYS_NS16550_IER
23 #define CONFIG_SYS_NS16550_IER  0x00
24 #endif
25 
26 #define UART_MCRVAL 0x00
27 #define UART_LCRVAL UART_LCR_8N1
28 
29 static inline void serial_out_shift(void *addr, int shift, int value)
30 {
31 #ifdef CONFIG_SYS_NS16550_PORT_MAPPED
32 	outb(value, (ulong)addr);
33 #elif defined(CONFIG_SYS_NS16550_MEM32) && defined(CONFIG_SYS_LITTLE_ENDIAN)
34 	out_le32(addr, value);
35 #elif defined(CONFIG_SYS_NS16550_MEM32) && defined(CONFIG_SYS_BIG_ENDIAN)
36 	out_be32(addr, value);
37 #elif defined(CONFIG_SYS_NS16550_MEM32)
38 	writel(value, addr);
39 #elif defined(CONFIG_SYS_BIG_ENDIAN)
40 	writeb(value, addr + (1 << shift) - 1);
41 #else
42 	writeb(value, addr);
43 #endif
44 }
45 
46 static inline int serial_in_shift(void *addr, int shift)
47 {
48 #ifdef CONFIG_SYS_NS16550_PORT_MAPPED
49 	return inb((ulong)addr);
50 #elif defined(CONFIG_SYS_NS16550_MEM32) && defined(CONFIG_SYS_LITTLE_ENDIAN)
51 	return in_le32(addr);
52 #elif defined(CONFIG_SYS_NS16550_MEM32) && defined(CONFIG_SYS_BIG_ENDIAN)
53 	return in_be32(addr);
54 #elif defined(CONFIG_SYS_NS16550_MEM32)
55 	return readl(addr);
56 #elif defined(CONFIG_SYS_BIG_ENDIAN)
57 	return readb(addr + (1 << shift) - 1);
58 #else
59 	return readb(addr);
60 #endif
61 }
62 
63 #include <debug_uart.h>
64 
65 static inline void _debug_uart_init(void)
66 {
67 	struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE;
68 	int baud_divisor;
69 
70 	baud_divisor = ns16550_calc_divisor(com_port, CONFIG_DEBUG_UART_CLOCK,
71 					    CONFIG_BAUDRATE);
72 	serial_dout(&com_port->ier, CONFIG_SYS_NS16550_IER);
73 	serial_dout(&com_port->mdr1, 0x7);
74 	serial_dout(&com_port->mcr, UART_MCRVAL);
75 	serial_dout(&com_port->fcr, UART_FCR_DEFVAL);
76 
77 	serial_dout(&com_port->lcr, UART_LCR_BKSE | UART_LCRVAL);
78 	serial_dout(&com_port->dll, baud_divisor & 0xff);
79 	serial_dout(&com_port->dlm, (baud_divisor >> 8) & 0xff);
80 	serial_dout(&com_port->lcr, UART_LCRVAL);
81 	serial_dout(&com_port->mdr1, 0x0);
82 }
83 
84 static inline void _debug_uart_putc(int ch)
85 {
86 	struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE;
87 
88 	while (!(serial_din(&com_port->lsr) & UART_LSR_THRE))
89 		;
90 	serial_dout(&com_port->thr, ch);
91 }
92 
93 DEBUG_UART_FUNCS
94 
95 #endif
96 
97 #if CONFIG_IS_ENABLED(DM_SERIAL)
98 
99 #if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
100 static int omap_serial_ofdata_to_platdata(struct udevice *dev)
101 {
102 	struct ns16550_platdata *plat = dev->platdata;
103 	fdt_addr_t addr;
104 	struct clk clk;
105 	int err;
106 
107 	/* try Processor Local Bus device first */
108 	addr = dev_read_addr(dev);
109 	if (addr == FDT_ADDR_T_NONE)
110 		return -EINVAL;
111 
112 	plat->base = (unsigned long)map_physmem(addr, 0, MAP_NOCACHE);
113 
114 	plat->reg_offset = dev_read_u32_default(dev, "reg-offset", 0);
115 	plat->reg_shift = 2;
116 
117 	err = clk_get_by_index(dev, 0, &clk);
118 	if (!err) {
119 		err = clk_get_rate(&clk);
120 		if (!IS_ERR_VALUE(err))
121 			plat->clock = err;
122 	} else if (err != -ENOENT && err != -ENODEV && err != -ENOSYS) {
123 		debug("omap serial failed to get clock\n");
124 		return err;
125 	}
126 
127 	if (!plat->clock)
128 		plat->clock = dev_read_u32_default(dev, "clock-frequency",
129 						   CONFIG_SYS_NS16550_CLK);
130 	if (!plat->clock) {
131 		debug("omap serial clock not defined\n");
132 		return -EINVAL;
133 	}
134 
135 	plat->fcr = UART_FCR_DEFVAL;
136 
137 	return 0;
138 }
139 
140 static const struct udevice_id omap_serial_ids[] = {
141 	{ .compatible = "ti,omap2-uart", },
142 	{ .compatible = "ti,omap3-uart", },
143 	{ .compatible = "ti,omap4-uart", },
144 	{ .compatible = "ti,am3352-uart", },
145 	{ .compatible = "ti,am4372-uart", },
146 	{ .compatible = "ti,dra742-uart", },
147 	{ .compatible = "ti,am654-uart", },
148 	{}
149 };
150 #endif /* OF_CONTROL && !OF_PLATDATA */
151 
152 #if CONFIG_IS_ENABLED(SERIAL_PRESENT)
153 U_BOOT_DRIVER(omap_serial) = {
154 	.name	= "omap_serial",
155 	.id	= UCLASS_SERIAL,
156 #if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
157 	.of_match = omap_serial_ids,
158 	.ofdata_to_platdata = omap_serial_ofdata_to_platdata,
159 	.platdata_auto_alloc_size = sizeof(struct ns16550_platdata),
160 #endif
161 	.priv_auto_alloc_size = sizeof(struct NS16550),
162 	.probe = ns16550_serial_probe,
163 	.ops	= &ns16550_serial_ops,
164 #if !CONFIG_IS_ENABLED(OF_CONTROL)
165 	.flags	= DM_FLAG_PRE_RELOC,
166 #endif
167 };
168 #endif
169 #endif /* DM_SERIAL */
170