1 /*
2  * Copyright (c) 2006-2022, RT-Thread Development Team
3  *
4  * SPDX-License-Identifier: Apache-2.0
5  *
6  * Change Logs:
7  * Date           Author       Notes
8  * 2022-3-08      GuEe-GUI     the first version
9  */
10 
11 #include <rthw.h>
12 #include <rtthread.h>
13 #include <rtdevice.h>
14 
15 #include <board.h>
16 
17 /*
18  * The Synopsys DesignWare 8250 has an extra feature whereby it detects if the
19  * LCR is written whilst busy. If it is, then a busy detect interrupt is
20  * raised, the LCR needs to be rewritten and the uart status register read.
21  */
22 
23 #define UART_RX             0    /* In: Receive buffer */
24 #define UART_TX             0    /* Out: Transmit buffer */
25 
26 #define UART_DLL            0    /* Out: Divisor Latch Low */
27 #define UART_DLM            1    /* Out: Divisor Latch High */
28 
29 #define UART_IER            1    /* Out: Interrupt Enable Register */
30 #define UART_IER_RDI        0x01 /* Enable receiver data interrupt */
31 
32 #define UART_SSR            0x22 /* In: Software Reset Register */
33 #define UART_USR            0x1f /* UART Status Register */
34 
35 #define UART_LCR            3    /* Out: Line Control Register */
36 #define UART_LCR_DLAB       0x80 /* Divisor latch access bit */
37 #define UART_LCR_SPAR       0x20 /* Stick parity (?) */
38 #define UART_LCR_PARITY     0x8  /* Parity Enable */
39 #define UART_LCR_STOP       0x4  /* Stop bits: 0=1 bit, 1=2 bits */
40 #define UART_LCR_WLEN8      0x3  /* Wordlength: 8 bits */
41 
42 #define UART_MCR            4    /* Out: Modem Control Register */
43 #define UART_MCR_RTS        0x02 /* RTS complement */
44 
45 #define UART_LSR            5    /* In: Line Status Register */
46 #define UART_LSR_BI         0x10 /* Break interrupt indicator */
47 #define UART_LSR_DR         0x01 /* Receiver data ready */
48 
49 #define UART_IIR            2    /* In: Interrupt ID Register */
50 #define UART_IIR_NO_INT     0x01 /* No interrupts pending */
51 #define UART_IIR_BUSY       0x07 /* DesignWare APB Busy Detect */
52 #define UART_IIR_RX_TIMEOUT 0x0c /* OMAP RX Timeout interrupt */
53 
54 #define UART_FCR            2    /* Out: FIFO Control Register */
55 #define UART_FCR_EN_FIFO    0x01 /* Enable the FIFO */
56 #define UART_FCR_CLEAR_RCVR 0x02 /* Clear the RCVR FIFO */
57 #define UART_FCR_CLEAR_XMIT 0x04 /* Clear the XMIT FIFO */
58 
59 #define UART_REG_SHIFT      0x2  /* Register Shift*/
60 #define UART_INPUT_CLK      24000000
61 
62 struct hw_uart_device
63 {
64     rt_ubase_t hw_base;
65     rt_uint32_t irqno;
66 #ifdef RT_USING_SMP
67     struct rt_spinlock spinlock;
68 #endif
69 };
70 
71 #define BSP_DEFINE_UART_DEVICE(no)                  \
72 static struct hw_uart_device _uart##no##_device =   \
73 {                                                   \
74     UART##no##_MMIO_BASE,                           \
75     UART##no##_IRQ                                  \
76 };                                                  \
77 static struct rt_serial_device _serial##no;
78 
79 #ifdef RT_USING_UART0
80 BSP_DEFINE_UART_DEVICE(0);
81 #endif
82 
83 #ifdef RT_USING_UART1
84 BSP_DEFINE_UART_DEVICE(1);
85 #endif
86 
87 #ifdef RT_USING_UART2
88 BSP_DEFINE_UART_DEVICE(2);
89 #endif
90 
91 #ifdef RT_USING_UART3
92 BSP_DEFINE_UART_DEVICE(3);
93 #endif
94 
95 #ifdef RT_USING_UART4
96 BSP_DEFINE_UART_DEVICE(4);
97 #endif
98 
99 #ifdef RT_USING_UART5
100 BSP_DEFINE_UART_DEVICE(5);
101 #endif
102 
103 #ifdef RT_USING_UART6
104 BSP_DEFINE_UART_DEVICE(6);
105 #endif
106 
107 #ifdef RT_USING_UART7
108 BSP_DEFINE_UART_DEVICE(7);
109 #endif
110 
111 #ifdef RT_USING_UART8
112 BSP_DEFINE_UART_DEVICE(8);
113 #endif
114 
115 #ifdef RT_USING_UART9
116 BSP_DEFINE_UART_DEVICE(9);
117 #endif
118 
dw8250_read32(rt_ubase_t addr,rt_ubase_t offset)119 rt_inline rt_uint32_t dw8250_read32(rt_ubase_t addr, rt_ubase_t offset)
120 {
121     return *((volatile rt_uint32_t *)(addr + (offset << UART_REG_SHIFT)));
122 }
123 
dw8250_write32(rt_ubase_t addr,rt_ubase_t offset,rt_uint32_t value)124 rt_inline void dw8250_write32(rt_ubase_t addr, rt_ubase_t offset, rt_uint32_t value)
125 {
126     *((volatile rt_uint32_t *)(addr + (offset << UART_REG_SHIFT))) = value;
127 
128     if (offset == UART_LCR)
129     {
130         int tries = 1000;
131 
132         /* Make sure LCR write wasn't ignored */
133         while (tries--)
134         {
135             unsigned int lcr = dw8250_read32(addr, UART_LCR);
136 
137             if ((value & ~UART_LCR_SPAR) == (lcr & ~UART_LCR_SPAR))
138             {
139                 return;
140             }
141 
142             dw8250_write32(addr, UART_FCR, UART_FCR_EN_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
143             dw8250_read32(addr, UART_RX);
144 
145             *((volatile rt_uint32_t *)(addr + (offset << UART_REG_SHIFT))) = value;
146         }
147     }
148 }
149 
dw8250_uart_configure(struct rt_serial_device * serial,struct serial_configure * cfg)150 static rt_err_t dw8250_uart_configure(struct rt_serial_device *serial, struct serial_configure *cfg)
151 {
152     rt_base_t base, rate;
153     struct hw_uart_device *uart;
154 
155     RT_ASSERT(serial != RT_NULL);
156     uart = (struct hw_uart_device *)serial->parent.user_data;
157     base = uart->hw_base;
158 
159 #ifdef RT_USING_SMP
160     rt_spin_lock_init(&uart->spinlock);
161 #endif
162 
163     /* Resset UART */
164     dw8250_write32(base, UART_SSR, 1);
165     dw8250_write32(base, UART_SSR, 0);
166 
167     dw8250_write32(base, UART_IER, !UART_IER_RDI);
168     dw8250_write32(base, UART_FCR, UART_FCR_EN_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
169 
170     /* Disable flow ctrl */
171     dw8250_write32(base, UART_MCR, 0);
172     /* Clear RTS */
173     dw8250_write32(base, UART_MCR, dw8250_read32(base, UART_MCR) | UART_MCR_RTS);
174 
175     rate = UART_INPUT_CLK / 16 / serial->config.baud_rate;
176 
177     /* Enable access DLL & DLH */
178     dw8250_write32(base, UART_LCR, dw8250_read32(base, UART_LCR) | UART_LCR_DLAB);
179     dw8250_write32(base, UART_DLL, (rate & 0xff));
180     dw8250_write32(base, UART_DLM, (rate & 0xff00) >> 8);
181     /* Clear DLAB bit */
182     dw8250_write32(base, UART_LCR, dw8250_read32(base, UART_LCR) & (~UART_LCR_DLAB));
183 
184     dw8250_write32(base, UART_LCR, (dw8250_read32(base, UART_LCR) & (~UART_LCR_WLEN8)) | UART_LCR_WLEN8);
185     dw8250_write32(base, UART_LCR, dw8250_read32(base, UART_LCR) & (~UART_LCR_STOP));
186     dw8250_write32(base, UART_LCR, dw8250_read32(base, UART_LCR) & (~UART_LCR_PARITY));
187 
188     dw8250_write32(base, UART_IER, UART_IER_RDI);
189 
190     return RT_EOK;
191 }
192 
dw8250_uart_control(struct rt_serial_device * serial,int cmd,void * arg)193 static rt_err_t dw8250_uart_control(struct rt_serial_device *serial, int cmd, void *arg)
194 {
195     struct hw_uart_device *uart;
196 
197     RT_ASSERT(serial != RT_NULL);
198     uart = (struct hw_uart_device *)serial->parent.user_data;
199 
200     switch (cmd)
201     {
202         case RT_DEVICE_CTRL_CLR_INT:
203             /* Disable rx irq */
204             dw8250_write32(uart->hw_base, UART_IER, !UART_IER_RDI);
205             rt_hw_interrupt_mask(uart->irqno);
206             break;
207 
208         case RT_DEVICE_CTRL_SET_INT:
209             /* Enable rx irq */
210             dw8250_write32(uart->hw_base, UART_IER, UART_IER_RDI);
211             rt_hw_interrupt_umask(uart->irqno);
212             break;
213     }
214 
215     return RT_EOK;
216 }
217 
dw8250_uart_putc(struct rt_serial_device * serial,char c)218 static int dw8250_uart_putc(struct rt_serial_device *serial, char c)
219 {
220     rt_base_t base;
221     struct hw_uart_device *uart;
222 
223     RT_ASSERT(serial != RT_NULL);
224     uart = (struct hw_uart_device *)serial->parent.user_data;
225     base = uart->hw_base;
226 
227     while ((dw8250_read32(base, UART_USR) & 0x2) == 0)
228     {
229     }
230 
231     dw8250_write32(base, UART_TX, c);
232 
233     return 1;
234 }
235 
dw8250_uart_getc(struct rt_serial_device * serial)236 static int dw8250_uart_getc(struct rt_serial_device *serial)
237 {
238     int ch = -1;
239     rt_base_t base;
240     struct hw_uart_device *uart;
241 
242     RT_ASSERT(serial != RT_NULL);
243     uart = (struct hw_uart_device *)serial->parent.user_data;
244     base = uart->hw_base;
245 
246     if ((dw8250_read32(base, UART_LSR) & 0x1))
247     {
248         ch = dw8250_read32(base, UART_RX) & 0xff;
249     }
250 
251     return ch;
252 }
253 
254 static const struct rt_uart_ops _uart_ops =
255 {
256     dw8250_uart_configure,
257     dw8250_uart_control,
258     dw8250_uart_putc,
259     dw8250_uart_getc,
260 };
261 
rt_hw_uart_isr(int irqno,void * param)262 static void rt_hw_uart_isr(int irqno, void *param)
263 {
264     unsigned int iir, status;
265     struct rt_serial_device *serial = (struct rt_serial_device *)param;
266     struct hw_uart_device *uart = (struct hw_uart_device *)serial->parent.user_data;
267 
268     iir = dw8250_read32(uart->hw_base, UART_IIR);
269 
270     /* If don't do this in non-DMA mode then the "RX TIMEOUT" interrupt will fire forever. */
271     if ((iir & 0x3f) == UART_IIR_RX_TIMEOUT)
272     {
273 #ifdef RT_USING_SMP
274         rt_base_t level = rt_spin_lock_irqsave(&uart->spinlock);
275 #endif
276 
277         status = dw8250_read32(uart->hw_base, UART_LSR);
278 
279         if (!(status & (UART_LSR_DR | UART_LSR_BI)))
280         {
281             dw8250_read32(uart->hw_base, UART_RX);
282         }
283 
284 #ifdef RT_USING_SMP
285         rt_spin_unlock_irqrestore(&uart->spinlock, level);
286 #endif
287     }
288 
289     if (!(iir & UART_IIR_NO_INT))
290     {
291         rt_hw_serial_isr(serial, RT_SERIAL_EVENT_RX_IND);
292     }
293 
294     if ((iir & UART_IIR_BUSY) == UART_IIR_BUSY)
295     {
296         /* Clear the USR */
297         dw8250_read32(uart->hw_base, UART_USR);
298 
299         return;
300     }
301 }
302 
rt_hw_uart_init(void)303 int rt_hw_uart_init(void)
304 {
305     rt_uint32_t value;
306     struct hw_uart_device* uart;
307     struct serial_configure config = RT_SERIAL_CONFIG_DEFAULT;
308     RT_UNUSED(value);
309 
310     config.baud_rate = 1500000;
311 
312 #define BSP_INSTALL_UART_DEVICE(no)     \
313     uart = &_uart##no##_device;         \
314     _serial##no.ops    = &_uart_ops;    \
315     _serial##no.config = config;        \
316     rt_hw_serial_register(&_serial##no, "uart" #no, RT_DEVICE_FLAG_RDWR | RT_DEVICE_FLAG_INT_RX, uart); \
317     rt_hw_interrupt_install(uart->irqno, rt_hw_uart_isr, &_serial##no, "uart" #no);
318 
319 #ifdef RT_USING_UART0
320     BSP_INSTALL_UART_DEVICE(0);
321 #endif
322 
323 #ifdef RT_USING_UART1
324     BSP_INSTALL_UART_DEVICE(1);
325 #endif
326 
327 #ifdef RT_USING_UART2
328     BSP_INSTALL_UART_DEVICE(2);
329 #endif
330 
331 #ifdef RT_USING_UART3
332     BSP_INSTALL_UART_DEVICE(3);
333 #endif
334 
335 #ifdef RT_USING_UART4
336     HWREG32(CRU_BASE + 0x370) = 0xFFFF0000 | (0x600) |(HWREG32(CRU_BASE + 0x370) & 0xF0FF);
337     value = HWREG32(0xFDC60000 + 0x48);
338     value &= ~((7 << 8) | (7 << 4));
339     value |= 0xFFFF0000 | (4 << 8) | (4 << 4);
340     HWREG32(0xFDC60000 + 0x48) = value;
341     HWREG32(0xFDC60000 + 0x30C) = 0xFFFF0000 | (1 << 14) | HWREG32(0xFDC60000 + 0x30C);
342     BSP_INSTALL_UART_DEVICE(4);
343 #endif
344 
345 #ifdef RT_USING_UART5
346     BSP_INSTALL_UART_DEVICE(5);
347 #endif
348 
349 #ifdef RT_USING_UART6
350     BSP_INSTALL_UART_DEVICE(6);
351 #endif
352 
353 #ifdef RT_USING_UART7
354     BSP_INSTALL_UART_DEVICE(7);
355 #endif
356 
357 #ifdef RT_USING_UART8
358     BSP_INSTALL_UART_DEVICE(8);
359 #endif
360 
361 #ifdef RT_USING_UART9
362     BSP_INSTALL_UART_DEVICE(9);
363 #endif
364 
365     return 0;
366 }
367