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8#include <common.h>
9#include <clk.h>
10#include <dm.h>
11#include <errno.h>
12#include <malloc.h>
13#include <watchdog.h>
14#include <serial.h>
15#include <debug_uart.h>
16#include <linux/compiler.h>
17#include <linux/delay.h>
18
19#include <asm/io.h>
20#ifdef CONFIG_DM_SERIAL
21#include <asm/arch/atmel_serial.h>
22#endif
23#include <asm/arch/clk.h>
24#include <asm/arch/hardware.h>
25
26#include "atmel_usart.h"
27
28DECLARE_GLOBAL_DATA_PTR;
29
30#ifndef CONFIG_DM_SERIAL
31static void atmel_serial_setbrg_internal(atmel_usart3_t *usart, int id,
32 int baudrate)
33{
34 unsigned long divisor;
35 unsigned long usart_hz;
36
37
38
39
40
41
42 usart_hz = get_usart_clk_rate(id);
43 divisor = (usart_hz / 16 + baudrate / 2) / baudrate;
44 writel(USART3_BF(CD, divisor), &usart->brgr);
45}
46
47static void atmel_serial_init_internal(atmel_usart3_t *usart)
48{
49
50
51
52
53 if (!(readl(&usart->csr) & USART3_BIT(TXEMPTY)))
54 __udelay(1000);
55
56 writel(USART3_BIT(RSTRX) | USART3_BIT(RSTTX), &usart->cr);
57}
58
59static void atmel_serial_activate(atmel_usart3_t *usart)
60{
61 writel((USART3_BF(USART_MODE, USART3_USART_MODE_NORMAL)
62 | USART3_BF(USCLKS, USART3_USCLKS_MCK)
63 | USART3_BF(CHRL, USART3_CHRL_8)
64 | USART3_BF(PAR, USART3_PAR_NONE)
65 | USART3_BF(NBSTOP, USART3_NBSTOP_1)),
66 &usart->mr);
67 writel(USART3_BIT(RXEN) | USART3_BIT(TXEN), &usart->cr);
68
69 __udelay(100);
70}
71
72static void atmel_serial_setbrg(void)
73{
74 atmel_serial_setbrg_internal((atmel_usart3_t *)CONFIG_USART_BASE,
75 CONFIG_USART_ID, gd->baudrate);
76}
77
78static int atmel_serial_init(void)
79{
80 atmel_usart3_t *usart = (atmel_usart3_t *)CONFIG_USART_BASE;
81
82 atmel_serial_init_internal(usart);
83 serial_setbrg();
84 atmel_serial_activate(usart);
85
86 return 0;
87}
88
89static void atmel_serial_putc(char c)
90{
91 atmel_usart3_t *usart = (atmel_usart3_t *)CONFIG_USART_BASE;
92
93 if (c == '\n')
94 serial_putc('\r');
95
96 while (!(readl(&usart->csr) & USART3_BIT(TXRDY)));
97 writel(c, &usart->thr);
98}
99
100static int atmel_serial_getc(void)
101{
102 atmel_usart3_t *usart = (atmel_usart3_t *)CONFIG_USART_BASE;
103
104 while (!(readl(&usart->csr) & USART3_BIT(RXRDY)))
105 WATCHDOG_RESET();
106 return readl(&usart->rhr);
107}
108
109static int atmel_serial_tstc(void)
110{
111 atmel_usart3_t *usart = (atmel_usart3_t *)CONFIG_USART_BASE;
112 return (readl(&usart->csr) & USART3_BIT(RXRDY)) != 0;
113}
114
115static struct serial_device atmel_serial_drv = {
116 .name = "atmel_serial",
117 .start = atmel_serial_init,
118 .stop = NULL,
119 .setbrg = atmel_serial_setbrg,
120 .putc = atmel_serial_putc,
121 .puts = default_serial_puts,
122 .getc = atmel_serial_getc,
123 .tstc = atmel_serial_tstc,
124};
125
126void atmel_serial_initialize(void)
127{
128 serial_register(&atmel_serial_drv);
129}
130
131__weak struct serial_device *default_serial_console(void)
132{
133 return &atmel_serial_drv;
134}
135#endif
136
137#ifdef CONFIG_DM_SERIAL
138enum serial_clk_type {
139 CLK_TYPE_NORMAL = 0,
140 CLK_TYPE_DBGU,
141};
142
143struct atmel_serial_priv {
144 atmel_usart3_t *usart;
145 ulong usart_clk_rate;
146};
147
148static void _atmel_serial_set_brg(atmel_usart3_t *usart,
149 ulong usart_clk_rate, int baudrate)
150{
151 unsigned long divisor;
152
153 divisor = (usart_clk_rate / 16 + baudrate / 2) / baudrate;
154 writel(USART3_BF(CD, divisor), &usart->brgr);
155}
156
157void _atmel_serial_init(atmel_usart3_t *usart,
158 ulong usart_clk_rate, int baudrate)
159{
160 writel(USART3_BIT(RXDIS) | USART3_BIT(TXDIS), &usart->cr);
161
162 writel((USART3_BF(USART_MODE, USART3_USART_MODE_NORMAL) |
163 USART3_BF(USCLKS, USART3_USCLKS_MCK) |
164 USART3_BF(CHRL, USART3_CHRL_8) |
165 USART3_BF(PAR, USART3_PAR_NONE) |
166 USART3_BF(NBSTOP, USART3_NBSTOP_1)), &usart->mr);
167
168 _atmel_serial_set_brg(usart, usart_clk_rate, baudrate);
169
170 writel(USART3_BIT(RSTRX) | USART3_BIT(RSTTX), &usart->cr);
171 writel(USART3_BIT(RXEN) | USART3_BIT(TXEN), &usart->cr);
172}
173
174int atmel_serial_setbrg(struct udevice *dev, int baudrate)
175{
176 struct atmel_serial_priv *priv = dev_get_priv(dev);
177
178 _atmel_serial_set_brg(priv->usart, priv->usart_clk_rate, baudrate);
179
180 return 0;
181}
182
183static int atmel_serial_getc(struct udevice *dev)
184{
185 struct atmel_serial_priv *priv = dev_get_priv(dev);
186
187 if (!(readl(&priv->usart->csr) & USART3_BIT(RXRDY)))
188 return -EAGAIN;
189
190 return readl(&priv->usart->rhr);
191}
192
193static int atmel_serial_putc(struct udevice *dev, const char ch)
194{
195 struct atmel_serial_priv *priv = dev_get_priv(dev);
196
197 if (!(readl(&priv->usart->csr) & USART3_BIT(TXRDY)))
198 return -EAGAIN;
199
200 writel(ch, &priv->usart->thr);
201
202 return 0;
203}
204
205static int atmel_serial_pending(struct udevice *dev, bool input)
206{
207 struct atmel_serial_priv *priv = dev_get_priv(dev);
208 uint32_t csr = readl(&priv->usart->csr);
209
210 if (input)
211 return csr & USART3_BIT(RXRDY) ? 1 : 0;
212 else
213 return csr & USART3_BIT(TXEMPTY) ? 0 : 1;
214}
215
216static const struct dm_serial_ops atmel_serial_ops = {
217 .putc = atmel_serial_putc,
218 .pending = atmel_serial_pending,
219 .getc = atmel_serial_getc,
220 .setbrg = atmel_serial_setbrg,
221};
222
223#if defined(CONFIG_SPL_BUILD) && !defined(CONFIG_SPL_CLK)
224static int atmel_serial_enable_clk(struct udevice *dev)
225{
226 struct atmel_serial_priv *priv = dev_get_priv(dev);
227
228
229 priv->usart_clk_rate = CONFIG_SPL_UART_CLOCK;
230
231 return 0;
232}
233#else
234static int atmel_serial_enable_clk(struct udevice *dev)
235{
236 struct atmel_serial_priv *priv = dev_get_priv(dev);
237 struct clk clk;
238 ulong clk_rate;
239 int ret;
240
241 ret = clk_get_by_index(dev, 0, &clk);
242 if (ret)
243 return -EINVAL;
244
245 if (dev_get_driver_data(dev) == CLK_TYPE_NORMAL) {
246 ret = clk_enable(&clk);
247 if (ret)
248 return ret;
249 }
250
251 clk_rate = clk_get_rate(&clk);
252 if (!clk_rate)
253 return -EINVAL;
254
255 priv->usart_clk_rate = clk_rate;
256
257 clk_free(&clk);
258
259 return 0;
260}
261#endif
262
263static int atmel_serial_probe(struct udevice *dev)
264{
265 struct atmel_serial_platdata *plat = dev->platdata;
266 struct atmel_serial_priv *priv = dev_get_priv(dev);
267 int ret;
268#if CONFIG_IS_ENABLED(OF_CONTROL)
269 fdt_addr_t addr_base;
270
271 addr_base = dev_read_addr(dev);
272 if (addr_base == FDT_ADDR_T_NONE)
273 return -ENODEV;
274
275 plat->base_addr = (uint32_t)addr_base;
276#endif
277 priv->usart = (atmel_usart3_t *)plat->base_addr;
278
279 ret = atmel_serial_enable_clk(dev);
280 if (ret)
281 return ret;
282
283 _atmel_serial_init(priv->usart, priv->usart_clk_rate, gd->baudrate);
284
285 return 0;
286}
287
288#if CONFIG_IS_ENABLED(OF_CONTROL)
289static const struct udevice_id atmel_serial_ids[] = {
290 {
291 .compatible = "atmel,at91sam9260-dbgu",
292 .data = CLK_TYPE_DBGU,
293 },
294 {
295 .compatible = "atmel,at91sam9260-usart",
296 .data = CLK_TYPE_NORMAL,
297 },
298 { }
299};
300#endif
301
302U_BOOT_DRIVER(serial_atmel) = {
303 .name = "serial_atmel",
304 .id = UCLASS_SERIAL,
305#if CONFIG_IS_ENABLED(OF_CONTROL)
306 .of_match = atmel_serial_ids,
307 .platdata_auto_alloc_size = sizeof(struct atmel_serial_platdata),
308#endif
309 .probe = atmel_serial_probe,
310 .ops = &atmel_serial_ops,
311#if !CONFIG_IS_ENABLED(OF_CONTROL)
312 .flags = DM_FLAG_PRE_RELOC,
313#endif
314 .priv_auto_alloc_size = sizeof(struct atmel_serial_priv),
315};
316#endif
317
318#ifdef CONFIG_DEBUG_UART_ATMEL
319static inline void _debug_uart_init(void)
320{
321 atmel_usart3_t *usart = (atmel_usart3_t *)CONFIG_DEBUG_UART_BASE;
322
323 _atmel_serial_init(usart, CONFIG_DEBUG_UART_CLOCK, CONFIG_BAUDRATE);
324}
325
326static inline void _debug_uart_putc(int ch)
327{
328 atmel_usart3_t *usart = (atmel_usart3_t *)CONFIG_DEBUG_UART_BASE;
329
330 while (!(readl(&usart->csr) & USART3_BIT(TXRDY)))
331 ;
332
333 writel(ch, &usart->thr);
334}
335
336DEBUG_UART_FUNCS
337#endif
338