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17#include <linux/clk.h>
18#include <linux/console.h>
19#include <linux/io.h>
20#include <linux/libfdt.h>
21#include <linux/module.h>
22#include <linux/of.h>
23#include <linux/of_fdt.h>
24#include <linux/of_device.h>
25#include <linux/platform_device.h>
26#include <linux/serial_8250.h>
27#include <linux/serial_core.h>
28#include <linux/serial_reg.h>
29
30#include "8250.h"
31
32
33struct ingenic_uart_config {
34 int tx_loadsz;
35 int fifosize;
36};
37
38struct ingenic_uart_data {
39 struct clk *clk_module;
40 struct clk *clk_baud;
41 int line;
42};
43
44static const struct of_device_id of_match[];
45
46#define UART_FCR_UME BIT(4)
47
48#define UART_MCR_MDCE BIT(7)
49#define UART_MCR_FCM BIT(6)
50
51static struct earlycon_device *early_device;
52
53static uint8_t early_in(struct uart_port *port, int offset)
54{
55 return readl(port->membase + (offset << 2));
56}
57
58static void early_out(struct uart_port *port, int offset, uint8_t value)
59{
60 writel(value, port->membase + (offset << 2));
61}
62
63static void ingenic_early_console_putc(struct uart_port *port, int c)
64{
65 uint8_t lsr;
66
67 do {
68 lsr = early_in(port, UART_LSR);
69 } while ((lsr & UART_LSR_TEMT) == 0);
70
71 early_out(port, UART_TX, c);
72}
73
74static void ingenic_early_console_write(struct console *console,
75 const char *s, unsigned int count)
76{
77 uart_console_write(&early_device->port, s, count,
78 ingenic_early_console_putc);
79}
80
81static void __init ingenic_early_console_setup_clock(struct earlycon_device *dev)
82{
83 void *fdt = initial_boot_params;
84 const __be32 *prop;
85 int offset;
86
87 offset = fdt_path_offset(fdt, "/ext");
88 if (offset < 0)
89 return;
90
91 prop = fdt_getprop(fdt, offset, "clock-frequency", NULL);
92 if (!prop)
93 return;
94
95 dev->port.uartclk = be32_to_cpup(prop);
96}
97
98static int __init ingenic_early_console_setup(struct earlycon_device *dev,
99 const char *opt)
100{
101 struct uart_port *port = &dev->port;
102 unsigned int baud, divisor;
103
104 if (!dev->port.membase)
105 return -ENODEV;
106
107 ingenic_early_console_setup_clock(dev);
108
109 baud = dev->baud ?: 115200;
110 divisor = DIV_ROUND_CLOSEST(port->uartclk, 16 * baud);
111
112 early_out(port, UART_IER, 0);
113 early_out(port, UART_LCR, UART_LCR_DLAB | UART_LCR_WLEN8);
114 early_out(port, UART_DLL, 0);
115 early_out(port, UART_DLM, 0);
116 early_out(port, UART_LCR, UART_LCR_WLEN8);
117 early_out(port, UART_FCR, UART_FCR_UME | UART_FCR_CLEAR_XMIT |
118 UART_FCR_CLEAR_RCVR | UART_FCR_ENABLE_FIFO);
119 early_out(port, UART_MCR, UART_MCR_RTS | UART_MCR_DTR);
120
121 early_out(port, UART_LCR, UART_LCR_DLAB | UART_LCR_WLEN8);
122 early_out(port, UART_DLL, divisor & 0xff);
123 early_out(port, UART_DLM, (divisor >> 8) & 0xff);
124 early_out(port, UART_LCR, UART_LCR_WLEN8);
125
126 early_device = dev;
127 dev->con->write = ingenic_early_console_write;
128
129 return 0;
130}
131
132EARLYCON_DECLARE(jz4740_uart, ingenic_early_console_setup);
133OF_EARLYCON_DECLARE(jz4740_uart, "ingenic,jz4740-uart",
134 ingenic_early_console_setup);
135
136EARLYCON_DECLARE(jz4775_uart, ingenic_early_console_setup);
137OF_EARLYCON_DECLARE(jz4775_uart, "ingenic,jz4775-uart",
138 ingenic_early_console_setup);
139
140EARLYCON_DECLARE(jz4780_uart, ingenic_early_console_setup);
141OF_EARLYCON_DECLARE(jz4780_uart, "ingenic,jz4780-uart",
142 ingenic_early_console_setup);
143
144static void ingenic_uart_serial_out(struct uart_port *p, int offset, int value)
145{
146 int ier;
147
148 switch (offset) {
149 case UART_FCR:
150
151 value |= UART_FCR_UME;
152 break;
153
154 case UART_IER:
155
156
157
158
159 value |= (value & 0x4) << 2;
160 break;
161
162 case UART_MCR:
163
164
165
166
167 ier = p->serial_in(p, UART_IER);
168
169 if (ier & UART_IER_MSI)
170 value |= UART_MCR_MDCE | UART_MCR_FCM;
171 else
172 value &= ~(UART_MCR_MDCE | UART_MCR_FCM);
173 break;
174
175 default:
176 break;
177 }
178
179 writeb(value, p->membase + (offset << p->regshift));
180}
181
182static unsigned int ingenic_uart_serial_in(struct uart_port *p, int offset)
183{
184 unsigned int value;
185
186 value = readb(p->membase + (offset << p->regshift));
187
188
189 switch (offset) {
190 case UART_FCR:
191 value &= ~UART_FCR_UME;
192 break;
193
194 case UART_MCR:
195 value &= ~(UART_MCR_MDCE | UART_MCR_FCM);
196 break;
197
198 default:
199 break;
200 }
201 return value;
202}
203
204static int ingenic_uart_probe(struct platform_device *pdev)
205{
206 struct uart_8250_port uart = {};
207 struct resource *regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
208 struct resource *irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
209 struct ingenic_uart_data *data;
210 const struct ingenic_uart_config *cdata;
211 const struct of_device_id *match;
212 int err, line;
213
214 match = of_match_device(of_match, &pdev->dev);
215 if (!match) {
216 dev_err(&pdev->dev, "Error: No device match found\n");
217 return -ENODEV;
218 }
219 cdata = match->data;
220
221 if (!regs || !irq) {
222 dev_err(&pdev->dev, "no registers/irq defined\n");
223 return -EINVAL;
224 }
225
226 data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
227 if (!data)
228 return -ENOMEM;
229
230 spin_lock_init(&uart.port.lock);
231 uart.port.type = PORT_16550A;
232 uart.port.flags = UPF_SKIP_TEST | UPF_IOREMAP | UPF_FIXED_TYPE;
233 uart.port.iotype = UPIO_MEM;
234 uart.port.mapbase = regs->start;
235 uart.port.regshift = 2;
236 uart.port.serial_out = ingenic_uart_serial_out;
237 uart.port.serial_in = ingenic_uart_serial_in;
238 uart.port.irq = irq->start;
239 uart.port.dev = &pdev->dev;
240 uart.port.fifosize = cdata->fifosize;
241 uart.tx_loadsz = cdata->tx_loadsz;
242 uart.capabilities = UART_CAP_FIFO | UART_CAP_RTOIE;
243
244
245 line = of_alias_get_id(pdev->dev.of_node, "serial");
246 if (line >= 0)
247 uart.port.line = line;
248
249 uart.port.membase = devm_ioremap(&pdev->dev, regs->start,
250 resource_size(regs));
251 if (!uart.port.membase)
252 return -ENOMEM;
253
254 data->clk_module = devm_clk_get(&pdev->dev, "module");
255 if (IS_ERR(data->clk_module)) {
256 err = PTR_ERR(data->clk_module);
257 if (err != -EPROBE_DEFER)
258 dev_err(&pdev->dev,
259 "unable to get module clock: %d\n", err);
260 return err;
261 }
262
263 data->clk_baud = devm_clk_get(&pdev->dev, "baud");
264 if (IS_ERR(data->clk_baud)) {
265 err = PTR_ERR(data->clk_baud);
266 if (err != -EPROBE_DEFER)
267 dev_err(&pdev->dev,
268 "unable to get baud clock: %d\n", err);
269 return err;
270 }
271
272 err = clk_prepare_enable(data->clk_module);
273 if (err) {
274 dev_err(&pdev->dev, "could not enable module clock: %d\n", err);
275 goto out;
276 }
277
278 err = clk_prepare_enable(data->clk_baud);
279 if (err) {
280 dev_err(&pdev->dev, "could not enable baud clock: %d\n", err);
281 goto out_disable_moduleclk;
282 }
283 uart.port.uartclk = clk_get_rate(data->clk_baud);
284
285 data->line = serial8250_register_8250_port(&uart);
286 if (data->line < 0) {
287 err = data->line;
288 goto out_disable_baudclk;
289 }
290
291 platform_set_drvdata(pdev, data);
292 return 0;
293
294out_disable_baudclk:
295 clk_disable_unprepare(data->clk_baud);
296out_disable_moduleclk:
297 clk_disable_unprepare(data->clk_module);
298out:
299 return err;
300}
301
302static int ingenic_uart_remove(struct platform_device *pdev)
303{
304 struct ingenic_uart_data *data = platform_get_drvdata(pdev);
305
306 serial8250_unregister_port(data->line);
307 clk_disable_unprepare(data->clk_module);
308 clk_disable_unprepare(data->clk_baud);
309 return 0;
310}
311
312static const struct ingenic_uart_config jz4740_uart_config = {
313 .tx_loadsz = 8,
314 .fifosize = 16,
315};
316
317static const struct ingenic_uart_config jz4760_uart_config = {
318 .tx_loadsz = 16,
319 .fifosize = 32,
320};
321
322static const struct ingenic_uart_config jz4780_uart_config = {
323 .tx_loadsz = 32,
324 .fifosize = 64,
325};
326
327static const struct of_device_id of_match[] = {
328 { .compatible = "ingenic,jz4740-uart", .data = &jz4740_uart_config },
329 { .compatible = "ingenic,jz4760-uart", .data = &jz4760_uart_config },
330 { .compatible = "ingenic,jz4775-uart", .data = &jz4760_uart_config },
331 { .compatible = "ingenic,jz4780-uart", .data = &jz4780_uart_config },
332 { }
333};
334MODULE_DEVICE_TABLE(of, of_match);
335
336static struct platform_driver ingenic_uart_platform_driver = {
337 .driver = {
338 .name = "ingenic-uart",
339 .of_match_table = of_match,
340 },
341 .probe = ingenic_uart_probe,
342 .remove = ingenic_uart_remove,
343};
344
345module_platform_driver(ingenic_uart_platform_driver);
346
347MODULE_AUTHOR("Paul Burton");
348MODULE_LICENSE("GPL");
349MODULE_DESCRIPTION("Ingenic SoC UART driver");
350
