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9#include <linux/clk.h>
10#include <linux/console.h>
11#include <linux/io.h>
12#include <linux/libfdt.h>
13#include <linux/module.h>
14#include <linux/of.h>
15#include <linux/of_fdt.h>
16#include <linux/of_device.h>
17#include <linux/platform_device.h>
18#include <linux/serial_8250.h>
19#include <linux/serial_core.h>
20#include <linux/serial_reg.h>
21
22#include "8250.h"
23
24
25struct ingenic_uart_config {
26 int tx_loadsz;
27 int fifosize;
28};
29
30struct ingenic_uart_data {
31 struct clk *clk_module;
32 struct clk *clk_baud;
33 int line;
34};
35
36static const struct of_device_id of_match[];
37
38#define UART_FCR_UME BIT(4)
39
40#define UART_MCR_MDCE BIT(7)
41#define UART_MCR_FCM BIT(6)
42
43static struct earlycon_device *early_device;
44
45static uint8_t early_in(struct uart_port *port, int offset)
46{
47 return readl(port->membase + (offset << 2));
48}
49
50static void early_out(struct uart_port *port, int offset, uint8_t value)
51{
52 writel(value, port->membase + (offset << 2));
53}
54
55static void ingenic_early_console_putc(struct uart_port *port, int c)
56{
57 uint8_t lsr;
58
59 do {
60 lsr = early_in(port, UART_LSR);
61 } while ((lsr & UART_LSR_TEMT) == 0);
62
63 early_out(port, UART_TX, c);
64}
65
66static void ingenic_early_console_write(struct console *console,
67 const char *s, unsigned int count)
68{
69 uart_console_write(&early_device->port, s, count,
70 ingenic_early_console_putc);
71}
72
73static void __init ingenic_early_console_setup_clock(struct earlycon_device *dev)
74{
75 void *fdt = initial_boot_params;
76 const __be32 *prop;
77 int offset;
78
79 offset = fdt_path_offset(fdt, "/ext");
80 if (offset < 0)
81 return;
82
83 prop = fdt_getprop(fdt, offset, "clock-frequency", NULL);
84 if (!prop)
85 return;
86
87 dev->port.uartclk = be32_to_cpup(prop);
88}
89
90static int __init ingenic_early_console_setup(struct earlycon_device *dev,
91 const char *opt)
92{
93 struct uart_port *port = &dev->port;
94 unsigned int divisor;
95 int baud = 115200;
96
97 if (!dev->port.membase)
98 return -ENODEV;
99
100 if (opt) {
101 unsigned int parity, bits, flow;
102
103 uart_parse_options(opt, &baud, &parity, &bits, &flow);
104 }
105
106 ingenic_early_console_setup_clock(dev);
107
108 if (dev->baud)
109 baud = dev->baud;
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
132OF_EARLYCON_DECLARE(jz4740_uart, "ingenic,jz4740-uart",
133 ingenic_early_console_setup);
134
135OF_EARLYCON_DECLARE(jz4770_uart, "ingenic,jz4770-uart",
136 ingenic_early_console_setup);
137
138OF_EARLYCON_DECLARE(jz4775_uart, "ingenic,jz4775-uart",
139 ingenic_early_console_setup);
140
141OF_EARLYCON_DECLARE(jz4780_uart, "ingenic,jz4780-uart",
142 ingenic_early_console_setup);
143
144OF_EARLYCON_DECLARE(x1000_uart, "ingenic,x1000-uart",
145 ingenic_early_console_setup);
146
147static void ingenic_uart_serial_out(struct uart_port *p, int offset, int value)
148{
149 int ier;
150
151 switch (offset) {
152 case UART_FCR:
153
154 value |= UART_FCR_UME;
155 break;
156
157 case UART_IER:
158
159
160
161
162 value |= (value & 0x4) << 2;
163 break;
164
165 case UART_MCR:
166
167
168
169
170 ier = p->serial_in(p, UART_IER);
171
172 if (ier & UART_IER_MSI)
173 value |= UART_MCR_MDCE | UART_MCR_FCM;
174 else
175 value &= ~(UART_MCR_MDCE | UART_MCR_FCM);
176 break;
177
178 default:
179 break;
180 }
181
182 writeb(value, p->membase + (offset << p->regshift));
183}
184
185static unsigned int ingenic_uart_serial_in(struct uart_port *p, int offset)
186{
187 unsigned int value;
188
189 value = readb(p->membase + (offset << p->regshift));
190
191
192 switch (offset) {
193 case UART_FCR:
194 value &= ~UART_FCR_UME;
195 break;
196
197 case UART_MCR:
198 value &= ~(UART_MCR_MDCE | UART_MCR_FCM);
199 break;
200
201 default:
202 break;
203 }
204 return value;
205}
206
207static int ingenic_uart_probe(struct platform_device *pdev)
208{
209 struct uart_8250_port uart = {};
210 struct resource *regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
211 struct resource *irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
212 struct ingenic_uart_data *data;
213 const struct ingenic_uart_config *cdata;
214 const struct of_device_id *match;
215 int err, line;
216
217 match = of_match_device(of_match, &pdev->dev);
218 if (!match) {
219 dev_err(&pdev->dev, "Error: No device match found\n");
220 return -ENODEV;
221 }
222 cdata = match->data;
223
224 if (!regs || !irq) {
225 dev_err(&pdev->dev, "no registers/irq defined\n");
226 return -EINVAL;
227 }
228
229 data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
230 if (!data)
231 return -ENOMEM;
232
233 spin_lock_init(&uart.port.lock);
234 uart.port.type = PORT_16550A;
235 uart.port.flags = UPF_SKIP_TEST | UPF_IOREMAP | UPF_FIXED_TYPE;
236 uart.port.iotype = UPIO_MEM;
237 uart.port.mapbase = regs->start;
238 uart.port.regshift = 2;
239 uart.port.serial_out = ingenic_uart_serial_out;
240 uart.port.serial_in = ingenic_uart_serial_in;
241 uart.port.irq = irq->start;
242 uart.port.dev = &pdev->dev;
243 uart.port.fifosize = cdata->fifosize;
244 uart.tx_loadsz = cdata->tx_loadsz;
245 uart.capabilities = UART_CAP_FIFO | UART_CAP_RTOIE;
246
247
248 line = of_alias_get_id(pdev->dev.of_node, "serial");
249 if (line >= 0)
250 uart.port.line = line;
251
252 uart.port.membase = devm_ioremap(&pdev->dev, regs->start,
253 resource_size(regs));
254 if (!uart.port.membase)
255 return -ENOMEM;
256
257 data->clk_module = devm_clk_get(&pdev->dev, "module");
258 if (IS_ERR(data->clk_module)) {
259 err = PTR_ERR(data->clk_module);
260 if (err != -EPROBE_DEFER)
261 dev_err(&pdev->dev,
262 "unable to get module clock: %d\n", err);
263 return err;
264 }
265
266 data->clk_baud = devm_clk_get(&pdev->dev, "baud");
267 if (IS_ERR(data->clk_baud)) {
268 err = PTR_ERR(data->clk_baud);
269 if (err != -EPROBE_DEFER)
270 dev_err(&pdev->dev,
271 "unable to get baud clock: %d\n", err);
272 return err;
273 }
274
275 err = clk_prepare_enable(data->clk_module);
276 if (err) {
277 dev_err(&pdev->dev, "could not enable module clock: %d\n", err);
278 goto out;
279 }
280
281 err = clk_prepare_enable(data->clk_baud);
282 if (err) {
283 dev_err(&pdev->dev, "could not enable baud clock: %d\n", err);
284 goto out_disable_moduleclk;
285 }
286 uart.port.uartclk = clk_get_rate(data->clk_baud);
287
288 data->line = serial8250_register_8250_port(&uart);
289 if (data->line < 0) {
290 err = data->line;
291 goto out_disable_baudclk;
292 }
293
294 platform_set_drvdata(pdev, data);
295 return 0;
296
297out_disable_baudclk:
298 clk_disable_unprepare(data->clk_baud);
299out_disable_moduleclk:
300 clk_disable_unprepare(data->clk_module);
301out:
302 return err;
303}
304
305static int ingenic_uart_remove(struct platform_device *pdev)
306{
307 struct ingenic_uart_data *data = platform_get_drvdata(pdev);
308
309 serial8250_unregister_port(data->line);
310 clk_disable_unprepare(data->clk_module);
311 clk_disable_unprepare(data->clk_baud);
312 return 0;
313}
314
315static const struct ingenic_uart_config jz4740_uart_config = {
316 .tx_loadsz = 8,
317 .fifosize = 16,
318};
319
320static const struct ingenic_uart_config jz4760_uart_config = {
321 .tx_loadsz = 16,
322 .fifosize = 32,
323};
324
325static const struct ingenic_uart_config jz4780_uart_config = {
326 .tx_loadsz = 32,
327 .fifosize = 64,
328};
329
330static const struct ingenic_uart_config x1000_uart_config = {
331 .tx_loadsz = 32,
332 .fifosize = 64,
333};
334
335static const struct of_device_id of_match[] = {
336 { .compatible = "ingenic,jz4740-uart", .data = &jz4740_uart_config },
337 { .compatible = "ingenic,jz4760-uart", .data = &jz4760_uart_config },
338 { .compatible = "ingenic,jz4770-uart", .data = &jz4760_uart_config },
339 { .compatible = "ingenic,jz4775-uart", .data = &jz4760_uart_config },
340 { .compatible = "ingenic,jz4780-uart", .data = &jz4780_uart_config },
341 { .compatible = "ingenic,x1000-uart", .data = &x1000_uart_config },
342 { }
343};
344MODULE_DEVICE_TABLE(of, of_match);
345
346static struct platform_driver ingenic_uart_platform_driver = {
347 .driver = {
348 .name = "ingenic-uart",
349 .of_match_table = of_match,
350 },
351 .probe = ingenic_uart_probe,
352 .remove = ingenic_uart_remove,
353};
354
355module_platform_driver(ingenic_uart_platform_driver);
356
357MODULE_AUTHOR("Paul Burton");
358MODULE_LICENSE("GPL");
359MODULE_DESCRIPTION("Ingenic SoC UART driver");
360
