blob: fbb39592d6ce7a76352539a964184cd12c30e9ef [file] [log] [blame]
Stoica Cosmin-Stefan1f68dbc2016-06-05 03:42:59 +03001/*
2 * (C) Copyright 2013-2016 Freescale Semiconductor, Inc.
3 *
4 * SPDX-License-Identifier: GPL-2.0+
5 */
6
7#include <common.h>
8#include <dm.h>
9#include <errno.h>
10#include <watchdog.h>
11#include <asm/io.h>
12#include <serial.h>
13#include <linux/compiler.h>
14#include <asm/arch/imx-regs.h>
15#include <asm/arch/clock.h>
16
17#define US1_TDRE (1 << 7)
18#define US1_RDRF (1 << 5)
19#define UC2_TE (1 << 3)
20#define LINCR1_INIT (1 << 0)
21#define LINCR1_MME (1 << 4)
22#define LINCR1_BF (1 << 7)
23#define LINSR_LINS_INITMODE (0x00001000)
24#define LINSR_LINS_MASK (0x0000F000)
25#define UARTCR_UART (1 << 0)
26#define UARTCR_WL0 (1 << 1)
27#define UARTCR_PCE (1 << 2)
28#define UARTCR_PC0 (1 << 3)
29#define UARTCR_TXEN (1 << 4)
30#define UARTCR_RXEN (1 << 5)
31#define UARTCR_PC1 (1 << 6)
32#define UARTSR_DTF (1 << 1)
33#define UARTSR_DRF (1 << 2)
34#define UARTSR_RMB (1 << 9)
35
36DECLARE_GLOBAL_DATA_PTR;
37
38#ifndef CONFIG_DM_SERIAL
39#error "The linflex serial driver does not have non-DM support."
40#endif
41
42static void _linflex_serial_setbrg(struct linflex_fsl *base, int baudrate)
43{
44 u32 clk = mxc_get_clock(MXC_UART_CLK);
45 u32 ibr, fbr;
46
47 if (!baudrate)
48 baudrate = CONFIG_BAUDRATE;
49
50 ibr = (u32) (clk / (16 * gd->baudrate));
51 fbr = (u32) (clk % (16 * gd->baudrate)) * 16;
52
53 __raw_writel(ibr, &base->linibrr);
54 __raw_writel(fbr, &base->linfbrr);
55}
56
57static int _linflex_serial_getc(struct linflex_fsl *base)
58{
59 char c;
60
61 if (!(__raw_readb(&base->uartsr) & UARTSR_DRF))
62 return -EAGAIN;
63
64 if (!(__raw_readl(&base->uartsr) & UARTSR_RMB))
65 return -EAGAIN;
66
67 c = __raw_readl(&base->bdrm);
68 __raw_writeb((__raw_readb(&base->uartsr) | (UARTSR_DRF | UARTSR_RMB)),
69 &base->uartsr);
70 return c;
71}
72
73static int _linflex_serial_putc(struct linflex_fsl *base, const char c)
74{
75 __raw_writeb(c, &base->bdrl);
76
77
78 if (!(__raw_readb(&base->uartsr) & UARTSR_DTF))
79 return -EAGAIN;
80
81 __raw_writeb((__raw_readb(&base->uartsr) | UARTSR_DTF), &base->uartsr);
82
83 return 0;
84}
85
86/*
87 * Initialise the serial port with the given baudrate. The settings
88 * are always 8 data bits, no parity, 1 stop bit, no start bits.
89 */
90static int _linflex_serial_init(struct linflex_fsl *base)
91{
92 volatile u32 ctrl;
93
94 /* set the Linflex in master mode amd activate by-pass filter */
95 ctrl = LINCR1_BF | LINCR1_MME;
96 __raw_writel(ctrl, &base->lincr1);
97
98 /* init mode */
99 ctrl |= LINCR1_INIT;
100 __raw_writel(ctrl, &base->lincr1);
101
102 /* waiting for init mode entry - TODO: add a timeout */
103 while ((__raw_readl(&base->linsr) & LINSR_LINS_MASK) !=
104 LINSR_LINS_INITMODE);
105
106 /* set UART bit to allow writing other bits */
107 __raw_writel(UARTCR_UART, &base->uartcr);
108
109 /* provide data bits, parity, stop bit, etc */
110 serial_setbrg();
111
112 /* 8 bit data, no parity, Tx and Rx enabled, UART mode */
113 __raw_writel(UARTCR_PC1 | UARTCR_RXEN | UARTCR_TXEN | UARTCR_PC0
114 | UARTCR_WL0 | UARTCR_UART, &base->uartcr);
115
116 ctrl = __raw_readl(&base->lincr1);
117 ctrl &= ~LINCR1_INIT;
118 __raw_writel(ctrl, &base->lincr1); /* end init mode */
119
120 return 0;
121}
122
123struct linflex_serial_platdata {
124 struct linflex_fsl *base_addr;
125 u8 port_id; /* do we need this? */
126};
127
128struct linflex_serial_priv {
129 struct linflex_fsl *lfuart;
130};
131
132int linflex_serial_setbrg(struct udevice *dev, int baudrate)
133{
134 struct linflex_serial_priv *priv = dev_get_priv(dev);
135
136 _linflex_serial_setbrg(priv->lfuart, baudrate);
137
138 return 0;
139}
140
141static int linflex_serial_getc(struct udevice *dev)
142{
143 struct linflex_serial_priv *priv = dev_get_priv(dev);
144
145 return _linflex_serial_getc(priv->lfuart);
146}
147
148static int linflex_serial_putc(struct udevice *dev, const char ch)
149{
150
151 struct linflex_serial_priv *priv = dev_get_priv(dev);
152
153 return _linflex_serial_putc(priv->lfuart, ch);
154}
155
156static int linflex_serial_pending(struct udevice *dev, bool input)
157{
158 struct linflex_serial_priv *priv = dev_get_priv(dev);
159 uint32_t uartsr = __raw_readl(&priv->lfuart->uartsr);
160
161 if (input)
162 return ((uartsr & UARTSR_DRF) && (uartsr & UARTSR_RMB)) ? 1 : 0;
163 else
164 return uartsr & UARTSR_DTF ? 0 : 1;
165}
166
167static void linflex_serial_init_internal(struct linflex_fsl *lfuart)
168{
169 _linflex_serial_init(lfuart);
170 _linflex_serial_setbrg(lfuart, CONFIG_BAUDRATE);
171 return;
172}
173
174static int linflex_serial_probe(struct udevice *dev)
175{
176 struct linflex_serial_platdata *plat = dev->platdata;
177 struct linflex_serial_priv *priv = dev_get_priv(dev);
178
179 priv->lfuart = (struct linflex_fsl *)plat->base_addr;
180 linflex_serial_init_internal(priv->lfuart);
181
182 return 0;
183}
184
185static const struct dm_serial_ops linflex_serial_ops = {
186 .putc = linflex_serial_putc,
187 .pending = linflex_serial_pending,
188 .getc = linflex_serial_getc,
189 .setbrg = linflex_serial_setbrg,
190};
191
192U_BOOT_DRIVER(serial_linflex) = {
193 .name = "serial_linflex",
194 .id = UCLASS_SERIAL,
195 .probe = linflex_serial_probe,
196 .ops = &linflex_serial_ops,
197 .flags = DM_FLAG_PRE_RELOC,
198 .priv_auto_alloc_size = sizeof(struct linflex_serial_priv),
199};
200
201#ifdef CONFIG_DEBUG_UART_LINFLEXUART
202
203#include <debug_uart.h>
204
205
206static inline void _debug_uart_init(void)
207{
208 struct linflex_fsl *base = (struct linflex_fsl *)CONFIG_DEBUG_UART_BASE;
209
210 linflex_serial_init_internal(base);
211}
212
213static inline void _debug_uart_putc(int ch)
214{
215 struct linflex_fsl *base = (struct linflex_fsl *)CONFIG_DEBUG_UART_BASE;
216
217 /* XXX: Is this OK? Should this use the non-DM version? */
218 _linflex_serial_putc(base, ch);
219}
220
221DEBUG_UART_FUNCS
222
223#endif /* CONFIG_DEBUG_UART_LINFLEXUART */