mpc52xx_uart.c 39 KB

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  1. /*
  2. * Driver for the PSC of the Freescale MPC52xx PSCs configured as UARTs.
  3. *
  4. * FIXME According to the usermanual the status bits in the status register
  5. * are only updated when the peripherals access the FIFO and not when the
  6. * CPU access them. So since we use this bits to know when we stop writing
  7. * and reading, they may not be updated in-time and a race condition may
  8. * exists. But I haven't be able to prove this and I don't care. But if
  9. * any problem arises, it might worth checking. The TX/RX FIFO Stats
  10. * registers should be used in addition.
  11. * Update: Actually, they seem updated ... At least the bits we use.
  12. *
  13. *
  14. * Maintainer : Sylvain Munaut <tnt@246tNt.com>
  15. *
  16. * Some of the code has been inspired/copied from the 2.4 code written
  17. * by Dale Farnsworth <dfarnsworth@mvista.com>.
  18. *
  19. * Copyright (C) 2008 Freescale Semiconductor Inc.
  20. * John Rigby <jrigby@gmail.com>
  21. * Added support for MPC5121
  22. * Copyright (C) 2006 Secret Lab Technologies Ltd.
  23. * Grant Likely <grant.likely@secretlab.ca>
  24. * Copyright (C) 2004-2006 Sylvain Munaut <tnt@246tNt.com>
  25. * Copyright (C) 2003 MontaVista, Software, Inc.
  26. *
  27. * This file is licensed under the terms of the GNU General Public License
  28. * version 2. This program is licensed "as is" without any warranty of any
  29. * kind, whether express or implied.
  30. */
  31. #undef DEBUG
  32. #include <linux/device.h>
  33. #include <linux/module.h>
  34. #include <linux/tty.h>
  35. #include <linux/serial.h>
  36. #include <linux/sysrq.h>
  37. #include <linux/console.h>
  38. #include <linux/delay.h>
  39. #include <linux/io.h>
  40. #include <linux/of.h>
  41. #include <linux/of_platform.h>
  42. #include <linux/clk.h>
  43. #include <asm/mpc52xx.h>
  44. #include <asm/mpc52xx_psc.h>
  45. #if defined(CONFIG_SERIAL_MPC52xx_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
  46. #define SUPPORT_SYSRQ
  47. #endif
  48. #include <linux/serial_core.h>
  49. /* We've been assigned a range on the "Low-density serial ports" major */
  50. #define SERIAL_PSC_MAJOR 204
  51. #define SERIAL_PSC_MINOR 148
  52. #define ISR_PASS_LIMIT 256 /* Max number of iteration in the interrupt */
  53. static struct uart_port mpc52xx_uart_ports[MPC52xx_PSC_MAXNUM];
  54. /* Rem: - We use the read_status_mask as a shadow of
  55. * psc->mpc52xx_psc_imr
  56. * - It's important that is array is all zero on start as we
  57. * use it to know if it's initialized or not ! If it's not sure
  58. * it's cleared, then a memset(...,0,...) should be added to
  59. * the console_init
  60. */
  61. /* lookup table for matching device nodes to index numbers */
  62. static struct device_node *mpc52xx_uart_nodes[MPC52xx_PSC_MAXNUM];
  63. static void mpc52xx_uart_of_enumerate(void);
  64. #define PSC(port) ((struct mpc52xx_psc __iomem *)((port)->membase))
  65. /* Forward declaration of the interruption handling routine */
  66. static irqreturn_t mpc52xx_uart_int(int irq, void *dev_id);
  67. static irqreturn_t mpc5xxx_uart_process_int(struct uart_port *port);
  68. /* Simple macro to test if a port is console or not. This one is taken
  69. * for serial_core.c and maybe should be moved to serial_core.h ? */
  70. #ifdef CONFIG_SERIAL_CORE_CONSOLE
  71. #define uart_console(port) \
  72. ((port)->cons && (port)->cons->index == (port)->line)
  73. #else
  74. #define uart_console(port) (0)
  75. #endif
  76. /* ======================================================================== */
  77. /* PSC fifo operations for isolating differences between 52xx and 512x */
  78. /* ======================================================================== */
  79. struct psc_ops {
  80. void (*fifo_init)(struct uart_port *port);
  81. int (*raw_rx_rdy)(struct uart_port *port);
  82. int (*raw_tx_rdy)(struct uart_port *port);
  83. int (*rx_rdy)(struct uart_port *port);
  84. int (*tx_rdy)(struct uart_port *port);
  85. int (*tx_empty)(struct uart_port *port);
  86. void (*stop_rx)(struct uart_port *port);
  87. void (*start_tx)(struct uart_port *port);
  88. void (*stop_tx)(struct uart_port *port);
  89. void (*rx_clr_irq)(struct uart_port *port);
  90. void (*tx_clr_irq)(struct uart_port *port);
  91. void (*write_char)(struct uart_port *port, unsigned char c);
  92. unsigned char (*read_char)(struct uart_port *port);
  93. void (*cw_disable_ints)(struct uart_port *port);
  94. void (*cw_restore_ints)(struct uart_port *port);
  95. unsigned int (*set_baudrate)(struct uart_port *port,
  96. struct ktermios *new,
  97. struct ktermios *old);
  98. int (*clock)(struct uart_port *port, int enable);
  99. int (*fifoc_init)(void);
  100. void (*fifoc_uninit)(void);
  101. void (*get_irq)(struct uart_port *, struct device_node *);
  102. irqreturn_t (*handle_irq)(struct uart_port *port);
  103. };
  104. /* setting the prescaler and divisor reg is common for all chips */
  105. static inline void mpc52xx_set_divisor(struct mpc52xx_psc __iomem *psc,
  106. u16 prescaler, unsigned int divisor)
  107. {
  108. /* select prescaler */
  109. out_be16(&psc->mpc52xx_psc_clock_select, prescaler);
  110. out_8(&psc->ctur, divisor >> 8);
  111. out_8(&psc->ctlr, divisor & 0xff);
  112. }
  113. #ifdef CONFIG_PPC_MPC52xx
  114. #define FIFO_52xx(port) ((struct mpc52xx_psc_fifo __iomem *)(PSC(port)+1))
  115. static void mpc52xx_psc_fifo_init(struct uart_port *port)
  116. {
  117. struct mpc52xx_psc __iomem *psc = PSC(port);
  118. struct mpc52xx_psc_fifo __iomem *fifo = FIFO_52xx(port);
  119. out_8(&fifo->rfcntl, 0x00);
  120. out_be16(&fifo->rfalarm, 0x1ff);
  121. out_8(&fifo->tfcntl, 0x07);
  122. out_be16(&fifo->tfalarm, 0x80);
  123. port->read_status_mask |= MPC52xx_PSC_IMR_RXRDY | MPC52xx_PSC_IMR_TXRDY;
  124. out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
  125. }
  126. static int mpc52xx_psc_raw_rx_rdy(struct uart_port *port)
  127. {
  128. return in_be16(&PSC(port)->mpc52xx_psc_status)
  129. & MPC52xx_PSC_SR_RXRDY;
  130. }
  131. static int mpc52xx_psc_raw_tx_rdy(struct uart_port *port)
  132. {
  133. return in_be16(&PSC(port)->mpc52xx_psc_status)
  134. & MPC52xx_PSC_SR_TXRDY;
  135. }
  136. static int mpc52xx_psc_rx_rdy(struct uart_port *port)
  137. {
  138. return in_be16(&PSC(port)->mpc52xx_psc_isr)
  139. & port->read_status_mask
  140. & MPC52xx_PSC_IMR_RXRDY;
  141. }
  142. static int mpc52xx_psc_tx_rdy(struct uart_port *port)
  143. {
  144. return in_be16(&PSC(port)->mpc52xx_psc_isr)
  145. & port->read_status_mask
  146. & MPC52xx_PSC_IMR_TXRDY;
  147. }
  148. static int mpc52xx_psc_tx_empty(struct uart_port *port)
  149. {
  150. return in_be16(&PSC(port)->mpc52xx_psc_status)
  151. & MPC52xx_PSC_SR_TXEMP;
  152. }
  153. static void mpc52xx_psc_start_tx(struct uart_port *port)
  154. {
  155. port->read_status_mask |= MPC52xx_PSC_IMR_TXRDY;
  156. out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
  157. }
  158. static void mpc52xx_psc_stop_tx(struct uart_port *port)
  159. {
  160. port->read_status_mask &= ~MPC52xx_PSC_IMR_TXRDY;
  161. out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
  162. }
  163. static void mpc52xx_psc_stop_rx(struct uart_port *port)
  164. {
  165. port->read_status_mask &= ~MPC52xx_PSC_IMR_RXRDY;
  166. out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
  167. }
  168. static void mpc52xx_psc_rx_clr_irq(struct uart_port *port)
  169. {
  170. }
  171. static void mpc52xx_psc_tx_clr_irq(struct uart_port *port)
  172. {
  173. }
  174. static void mpc52xx_psc_write_char(struct uart_port *port, unsigned char c)
  175. {
  176. out_8(&PSC(port)->mpc52xx_psc_buffer_8, c);
  177. }
  178. static unsigned char mpc52xx_psc_read_char(struct uart_port *port)
  179. {
  180. return in_8(&PSC(port)->mpc52xx_psc_buffer_8);
  181. }
  182. static void mpc52xx_psc_cw_disable_ints(struct uart_port *port)
  183. {
  184. out_be16(&PSC(port)->mpc52xx_psc_imr, 0);
  185. }
  186. static void mpc52xx_psc_cw_restore_ints(struct uart_port *port)
  187. {
  188. out_be16(&PSC(port)->mpc52xx_psc_imr, port->read_status_mask);
  189. }
  190. static unsigned int mpc5200_psc_set_baudrate(struct uart_port *port,
  191. struct ktermios *new,
  192. struct ktermios *old)
  193. {
  194. unsigned int baud;
  195. unsigned int divisor;
  196. /* The 5200 has a fixed /32 prescaler, uartclk contains the ipb freq */
  197. baud = uart_get_baud_rate(port, new, old,
  198. port->uartclk / (32 * 0xffff) + 1,
  199. port->uartclk / 32);
  200. divisor = (port->uartclk + 16 * baud) / (32 * baud);
  201. /* enable the /32 prescaler and set the divisor */
  202. mpc52xx_set_divisor(PSC(port), 0xdd00, divisor);
  203. return baud;
  204. }
  205. static unsigned int mpc5200b_psc_set_baudrate(struct uart_port *port,
  206. struct ktermios *new,
  207. struct ktermios *old)
  208. {
  209. unsigned int baud;
  210. unsigned int divisor;
  211. u16 prescaler;
  212. /* The 5200B has a selectable /4 or /32 prescaler, uartclk contains the
  213. * ipb freq */
  214. baud = uart_get_baud_rate(port, new, old,
  215. port->uartclk / (32 * 0xffff) + 1,
  216. port->uartclk / 4);
  217. divisor = (port->uartclk + 2 * baud) / (4 * baud);
  218. /* select the proper prescaler and set the divisor */
  219. if (divisor > 0xffff) {
  220. divisor = (divisor + 4) / 8;
  221. prescaler = 0xdd00; /* /32 */
  222. } else
  223. prescaler = 0xff00; /* /4 */
  224. mpc52xx_set_divisor(PSC(port), prescaler, divisor);
  225. return baud;
  226. }
  227. static void mpc52xx_psc_get_irq(struct uart_port *port, struct device_node *np)
  228. {
  229. port->irqflags = IRQF_DISABLED;
  230. port->irq = irq_of_parse_and_map(np, 0);
  231. }
  232. /* 52xx specific interrupt handler. The caller holds the port lock */
  233. static irqreturn_t mpc52xx_psc_handle_irq(struct uart_port *port)
  234. {
  235. return mpc5xxx_uart_process_int(port);
  236. }
  237. static struct psc_ops mpc52xx_psc_ops = {
  238. .fifo_init = mpc52xx_psc_fifo_init,
  239. .raw_rx_rdy = mpc52xx_psc_raw_rx_rdy,
  240. .raw_tx_rdy = mpc52xx_psc_raw_tx_rdy,
  241. .rx_rdy = mpc52xx_psc_rx_rdy,
  242. .tx_rdy = mpc52xx_psc_tx_rdy,
  243. .tx_empty = mpc52xx_psc_tx_empty,
  244. .stop_rx = mpc52xx_psc_stop_rx,
  245. .start_tx = mpc52xx_psc_start_tx,
  246. .stop_tx = mpc52xx_psc_stop_tx,
  247. .rx_clr_irq = mpc52xx_psc_rx_clr_irq,
  248. .tx_clr_irq = mpc52xx_psc_tx_clr_irq,
  249. .write_char = mpc52xx_psc_write_char,
  250. .read_char = mpc52xx_psc_read_char,
  251. .cw_disable_ints = mpc52xx_psc_cw_disable_ints,
  252. .cw_restore_ints = mpc52xx_psc_cw_restore_ints,
  253. .set_baudrate = mpc5200_psc_set_baudrate,
  254. .get_irq = mpc52xx_psc_get_irq,
  255. .handle_irq = mpc52xx_psc_handle_irq,
  256. };
  257. static struct psc_ops mpc5200b_psc_ops = {
  258. .fifo_init = mpc52xx_psc_fifo_init,
  259. .raw_rx_rdy = mpc52xx_psc_raw_rx_rdy,
  260. .raw_tx_rdy = mpc52xx_psc_raw_tx_rdy,
  261. .rx_rdy = mpc52xx_psc_rx_rdy,
  262. .tx_rdy = mpc52xx_psc_tx_rdy,
  263. .tx_empty = mpc52xx_psc_tx_empty,
  264. .stop_rx = mpc52xx_psc_stop_rx,
  265. .start_tx = mpc52xx_psc_start_tx,
  266. .stop_tx = mpc52xx_psc_stop_tx,
  267. .rx_clr_irq = mpc52xx_psc_rx_clr_irq,
  268. .tx_clr_irq = mpc52xx_psc_tx_clr_irq,
  269. .write_char = mpc52xx_psc_write_char,
  270. .read_char = mpc52xx_psc_read_char,
  271. .cw_disable_ints = mpc52xx_psc_cw_disable_ints,
  272. .cw_restore_ints = mpc52xx_psc_cw_restore_ints,
  273. .set_baudrate = mpc5200b_psc_set_baudrate,
  274. .get_irq = mpc52xx_psc_get_irq,
  275. .handle_irq = mpc52xx_psc_handle_irq,
  276. };
  277. #endif /* CONFIG_MPC52xx */
  278. #ifdef CONFIG_PPC_MPC512x
  279. #define FIFO_512x(port) ((struct mpc512x_psc_fifo __iomem *)(PSC(port)+1))
  280. /* PSC FIFO Controller for mpc512x */
  281. struct psc_fifoc {
  282. u32 fifoc_cmd;
  283. u32 fifoc_int;
  284. u32 fifoc_dma;
  285. u32 fifoc_axe;
  286. u32 fifoc_debug;
  287. };
  288. static struct psc_fifoc __iomem *psc_fifoc;
  289. static unsigned int psc_fifoc_irq;
  290. static void mpc512x_psc_fifo_init(struct uart_port *port)
  291. {
  292. /* /32 prescaler */
  293. out_be16(&PSC(port)->mpc52xx_psc_clock_select, 0xdd00);
  294. out_be32(&FIFO_512x(port)->txcmd, MPC512x_PSC_FIFO_RESET_SLICE);
  295. out_be32(&FIFO_512x(port)->txcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
  296. out_be32(&FIFO_512x(port)->txalarm, 1);
  297. out_be32(&FIFO_512x(port)->tximr, 0);
  298. out_be32(&FIFO_512x(port)->rxcmd, MPC512x_PSC_FIFO_RESET_SLICE);
  299. out_be32(&FIFO_512x(port)->rxcmd, MPC512x_PSC_FIFO_ENABLE_SLICE);
  300. out_be32(&FIFO_512x(port)->rxalarm, 1);
  301. out_be32(&FIFO_512x(port)->rximr, 0);
  302. out_be32(&FIFO_512x(port)->tximr, MPC512x_PSC_FIFO_ALARM);
  303. out_be32(&FIFO_512x(port)->rximr, MPC512x_PSC_FIFO_ALARM);
  304. }
  305. static int mpc512x_psc_raw_rx_rdy(struct uart_port *port)
  306. {
  307. return !(in_be32(&FIFO_512x(port)->rxsr) & MPC512x_PSC_FIFO_EMPTY);
  308. }
  309. static int mpc512x_psc_raw_tx_rdy(struct uart_port *port)
  310. {
  311. return !(in_be32(&FIFO_512x(port)->txsr) & MPC512x_PSC_FIFO_FULL);
  312. }
  313. static int mpc512x_psc_rx_rdy(struct uart_port *port)
  314. {
  315. return in_be32(&FIFO_512x(port)->rxsr)
  316. & in_be32(&FIFO_512x(port)->rximr)
  317. & MPC512x_PSC_FIFO_ALARM;
  318. }
  319. static int mpc512x_psc_tx_rdy(struct uart_port *port)
  320. {
  321. return in_be32(&FIFO_512x(port)->txsr)
  322. & in_be32(&FIFO_512x(port)->tximr)
  323. & MPC512x_PSC_FIFO_ALARM;
  324. }
  325. static int mpc512x_psc_tx_empty(struct uart_port *port)
  326. {
  327. return in_be32(&FIFO_512x(port)->txsr)
  328. & MPC512x_PSC_FIFO_EMPTY;
  329. }
  330. static void mpc512x_psc_stop_rx(struct uart_port *port)
  331. {
  332. unsigned long rx_fifo_imr;
  333. rx_fifo_imr = in_be32(&FIFO_512x(port)->rximr);
  334. rx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
  335. out_be32(&FIFO_512x(port)->rximr, rx_fifo_imr);
  336. }
  337. static void mpc512x_psc_start_tx(struct uart_port *port)
  338. {
  339. unsigned long tx_fifo_imr;
  340. tx_fifo_imr = in_be32(&FIFO_512x(port)->tximr);
  341. tx_fifo_imr |= MPC512x_PSC_FIFO_ALARM;
  342. out_be32(&FIFO_512x(port)->tximr, tx_fifo_imr);
  343. }
  344. static void mpc512x_psc_stop_tx(struct uart_port *port)
  345. {
  346. unsigned long tx_fifo_imr;
  347. tx_fifo_imr = in_be32(&FIFO_512x(port)->tximr);
  348. tx_fifo_imr &= ~MPC512x_PSC_FIFO_ALARM;
  349. out_be32(&FIFO_512x(port)->tximr, tx_fifo_imr);
  350. }
  351. static void mpc512x_psc_rx_clr_irq(struct uart_port *port)
  352. {
  353. out_be32(&FIFO_512x(port)->rxisr, in_be32(&FIFO_512x(port)->rxisr));
  354. }
  355. static void mpc512x_psc_tx_clr_irq(struct uart_port *port)
  356. {
  357. out_be32(&FIFO_512x(port)->txisr, in_be32(&FIFO_512x(port)->txisr));
  358. }
  359. static void mpc512x_psc_write_char(struct uart_port *port, unsigned char c)
  360. {
  361. out_8(&FIFO_512x(port)->txdata_8, c);
  362. }
  363. static unsigned char mpc512x_psc_read_char(struct uart_port *port)
  364. {
  365. return in_8(&FIFO_512x(port)->rxdata_8);
  366. }
  367. static void mpc512x_psc_cw_disable_ints(struct uart_port *port)
  368. {
  369. port->read_status_mask =
  370. in_be32(&FIFO_512x(port)->tximr) << 16 |
  371. in_be32(&FIFO_512x(port)->rximr);
  372. out_be32(&FIFO_512x(port)->tximr, 0);
  373. out_be32(&FIFO_512x(port)->rximr, 0);
  374. }
  375. static void mpc512x_psc_cw_restore_ints(struct uart_port *port)
  376. {
  377. out_be32(&FIFO_512x(port)->tximr,
  378. (port->read_status_mask >> 16) & 0x7f);
  379. out_be32(&FIFO_512x(port)->rximr, port->read_status_mask & 0x7f);
  380. }
  381. static unsigned int mpc512x_psc_set_baudrate(struct uart_port *port,
  382. struct ktermios *new,
  383. struct ktermios *old)
  384. {
  385. unsigned int baud;
  386. unsigned int divisor;
  387. /*
  388. * The "MPC5121e Microcontroller Reference Manual, Rev. 3" says on
  389. * pg. 30-10 that the chip supports a /32 and a /10 prescaler.
  390. * Furthermore, it states that "After reset, the prescaler by 10
  391. * for the UART mode is selected", but the reset register value is
  392. * 0x0000 which means a /32 prescaler. This is wrong.
  393. *
  394. * In reality using /32 prescaler doesn't work, as it is not supported!
  395. * Use /16 or /10 prescaler, see "MPC5121e Hardware Design Guide",
  396. * Chapter 4.1 PSC in UART Mode.
  397. * Calculate with a /16 prescaler here.
  398. */
  399. /* uartclk contains the ips freq */
  400. baud = uart_get_baud_rate(port, new, old,
  401. port->uartclk / (16 * 0xffff) + 1,
  402. port->uartclk / 16);
  403. divisor = (port->uartclk + 8 * baud) / (16 * baud);
  404. /* enable the /16 prescaler and set the divisor */
  405. mpc52xx_set_divisor(PSC(port), 0xdd00, divisor);
  406. return baud;
  407. }
  408. /* Init PSC FIFO Controller */
  409. static int __init mpc512x_psc_fifoc_init(void)
  410. {
  411. struct device_node *np;
  412. np = of_find_compatible_node(NULL, NULL,
  413. "fsl,mpc5121-psc-fifo");
  414. if (!np) {
  415. pr_err("%s: Can't find FIFOC node\n", __func__);
  416. return -ENODEV;
  417. }
  418. psc_fifoc = of_iomap(np, 0);
  419. if (!psc_fifoc) {
  420. pr_err("%s: Can't map FIFOC\n", __func__);
  421. return -ENODEV;
  422. }
  423. psc_fifoc_irq = irq_of_parse_and_map(np, 0);
  424. of_node_put(np);
  425. if (psc_fifoc_irq == NO_IRQ) {
  426. pr_err("%s: Can't get FIFOC irq\n", __func__);
  427. iounmap(psc_fifoc);
  428. return -ENODEV;
  429. }
  430. return 0;
  431. }
  432. static void __exit mpc512x_psc_fifoc_uninit(void)
  433. {
  434. iounmap(psc_fifoc);
  435. }
  436. /* 512x specific interrupt handler. The caller holds the port lock */
  437. static irqreturn_t mpc512x_psc_handle_irq(struct uart_port *port)
  438. {
  439. unsigned long fifoc_int;
  440. int psc_num;
  441. /* Read pending PSC FIFOC interrupts */
  442. fifoc_int = in_be32(&psc_fifoc->fifoc_int);
  443. /* Check if it is an interrupt for this port */
  444. psc_num = (port->mapbase & 0xf00) >> 8;
  445. if (test_bit(psc_num, &fifoc_int) ||
  446. test_bit(psc_num + 16, &fifoc_int))
  447. return mpc5xxx_uart_process_int(port);
  448. return IRQ_NONE;
  449. }
  450. static int mpc512x_psc_clock(struct uart_port *port, int enable)
  451. {
  452. struct clk *psc_clk;
  453. int psc_num;
  454. char clk_name[10];
  455. if (uart_console(port))
  456. return 0;
  457. psc_num = (port->mapbase & 0xf00) >> 8;
  458. snprintf(clk_name, sizeof(clk_name), "psc%d_clk", psc_num);
  459. psc_clk = clk_get(port->dev, clk_name);
  460. if (IS_ERR(psc_clk)) {
  461. dev_err(port->dev, "Failed to get PSC clock entry!\n");
  462. return -ENODEV;
  463. }
  464. dev_dbg(port->dev, "%s %sable\n", clk_name, enable ? "en" : "dis");
  465. if (enable)
  466. clk_enable(psc_clk);
  467. else
  468. clk_disable(psc_clk);
  469. return 0;
  470. }
  471. static void mpc512x_psc_get_irq(struct uart_port *port, struct device_node *np)
  472. {
  473. port->irqflags = IRQF_SHARED;
  474. port->irq = psc_fifoc_irq;
  475. }
  476. static struct psc_ops mpc512x_psc_ops = {
  477. .fifo_init = mpc512x_psc_fifo_init,
  478. .raw_rx_rdy = mpc512x_psc_raw_rx_rdy,
  479. .raw_tx_rdy = mpc512x_psc_raw_tx_rdy,
  480. .rx_rdy = mpc512x_psc_rx_rdy,
  481. .tx_rdy = mpc512x_psc_tx_rdy,
  482. .tx_empty = mpc512x_psc_tx_empty,
  483. .stop_rx = mpc512x_psc_stop_rx,
  484. .start_tx = mpc512x_psc_start_tx,
  485. .stop_tx = mpc512x_psc_stop_tx,
  486. .rx_clr_irq = mpc512x_psc_rx_clr_irq,
  487. .tx_clr_irq = mpc512x_psc_tx_clr_irq,
  488. .write_char = mpc512x_psc_write_char,
  489. .read_char = mpc512x_psc_read_char,
  490. .cw_disable_ints = mpc512x_psc_cw_disable_ints,
  491. .cw_restore_ints = mpc512x_psc_cw_restore_ints,
  492. .set_baudrate = mpc512x_psc_set_baudrate,
  493. .clock = mpc512x_psc_clock,
  494. .fifoc_init = mpc512x_psc_fifoc_init,
  495. .fifoc_uninit = mpc512x_psc_fifoc_uninit,
  496. .get_irq = mpc512x_psc_get_irq,
  497. .handle_irq = mpc512x_psc_handle_irq,
  498. };
  499. #endif
  500. static struct psc_ops *psc_ops;
  501. /* ======================================================================== */
  502. /* UART operations */
  503. /* ======================================================================== */
  504. static unsigned int
  505. mpc52xx_uart_tx_empty(struct uart_port *port)
  506. {
  507. return psc_ops->tx_empty(port) ? TIOCSER_TEMT : 0;
  508. }
  509. static void
  510. mpc52xx_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
  511. {
  512. if (mctrl & TIOCM_RTS)
  513. out_8(&PSC(port)->op1, MPC52xx_PSC_OP_RTS);
  514. else
  515. out_8(&PSC(port)->op0, MPC52xx_PSC_OP_RTS);
  516. }
  517. static unsigned int
  518. mpc52xx_uart_get_mctrl(struct uart_port *port)
  519. {
  520. unsigned int ret = TIOCM_DSR;
  521. u8 status = in_8(&PSC(port)->mpc52xx_psc_ipcr);
  522. if (!(status & MPC52xx_PSC_CTS))
  523. ret |= TIOCM_CTS;
  524. if (!(status & MPC52xx_PSC_DCD))
  525. ret |= TIOCM_CAR;
  526. return ret;
  527. }
  528. static void
  529. mpc52xx_uart_stop_tx(struct uart_port *port)
  530. {
  531. /* port->lock taken by caller */
  532. psc_ops->stop_tx(port);
  533. }
  534. static void
  535. mpc52xx_uart_start_tx(struct uart_port *port)
  536. {
  537. /* port->lock taken by caller */
  538. psc_ops->start_tx(port);
  539. }
  540. static void
  541. mpc52xx_uart_send_xchar(struct uart_port *port, char ch)
  542. {
  543. unsigned long flags;
  544. spin_lock_irqsave(&port->lock, flags);
  545. port->x_char = ch;
  546. if (ch) {
  547. /* Make sure tx interrupts are on */
  548. /* Truly necessary ??? They should be anyway */
  549. psc_ops->start_tx(port);
  550. }
  551. spin_unlock_irqrestore(&port->lock, flags);
  552. }
  553. static void
  554. mpc52xx_uart_stop_rx(struct uart_port *port)
  555. {
  556. /* port->lock taken by caller */
  557. psc_ops->stop_rx(port);
  558. }
  559. static void
  560. mpc52xx_uart_enable_ms(struct uart_port *port)
  561. {
  562. struct mpc52xx_psc __iomem *psc = PSC(port);
  563. /* clear D_*-bits by reading them */
  564. in_8(&psc->mpc52xx_psc_ipcr);
  565. /* enable CTS and DCD as IPC interrupts */
  566. out_8(&psc->mpc52xx_psc_acr, MPC52xx_PSC_IEC_CTS | MPC52xx_PSC_IEC_DCD);
  567. port->read_status_mask |= MPC52xx_PSC_IMR_IPC;
  568. out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
  569. }
  570. static void
  571. mpc52xx_uart_break_ctl(struct uart_port *port, int ctl)
  572. {
  573. unsigned long flags;
  574. spin_lock_irqsave(&port->lock, flags);
  575. if (ctl == -1)
  576. out_8(&PSC(port)->command, MPC52xx_PSC_START_BRK);
  577. else
  578. out_8(&PSC(port)->command, MPC52xx_PSC_STOP_BRK);
  579. spin_unlock_irqrestore(&port->lock, flags);
  580. }
  581. static int
  582. mpc52xx_uart_startup(struct uart_port *port)
  583. {
  584. struct mpc52xx_psc __iomem *psc = PSC(port);
  585. int ret;
  586. if (psc_ops->clock) {
  587. ret = psc_ops->clock(port, 1);
  588. if (ret)
  589. return ret;
  590. }
  591. /* Request IRQ */
  592. ret = request_irq(port->irq, mpc52xx_uart_int,
  593. port->irqflags, "mpc52xx_psc_uart", port);
  594. if (ret)
  595. return ret;
  596. /* Reset/activate the port, clear and enable interrupts */
  597. out_8(&psc->command, MPC52xx_PSC_RST_RX);
  598. out_8(&psc->command, MPC52xx_PSC_RST_TX);
  599. out_be32(&psc->sicr, 0); /* UART mode DCD ignored */
  600. psc_ops->fifo_init(port);
  601. out_8(&psc->command, MPC52xx_PSC_TX_ENABLE);
  602. out_8(&psc->command, MPC52xx_PSC_RX_ENABLE);
  603. return 0;
  604. }
  605. static void
  606. mpc52xx_uart_shutdown(struct uart_port *port)
  607. {
  608. struct mpc52xx_psc __iomem *psc = PSC(port);
  609. /* Shut down the port. Leave TX active if on a console port */
  610. out_8(&psc->command, MPC52xx_PSC_RST_RX);
  611. if (!uart_console(port))
  612. out_8(&psc->command, MPC52xx_PSC_RST_TX);
  613. port->read_status_mask = 0;
  614. out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask);
  615. if (psc_ops->clock)
  616. psc_ops->clock(port, 0);
  617. /* Release interrupt */
  618. free_irq(port->irq, port);
  619. }
  620. static void
  621. mpc52xx_uart_set_termios(struct uart_port *port, struct ktermios *new,
  622. struct ktermios *old)
  623. {
  624. struct mpc52xx_psc __iomem *psc = PSC(port);
  625. unsigned long flags;
  626. unsigned char mr1, mr2;
  627. unsigned int j;
  628. unsigned int baud;
  629. /* Prepare what we're gonna write */
  630. mr1 = 0;
  631. switch (new->c_cflag & CSIZE) {
  632. case CS5: mr1 |= MPC52xx_PSC_MODE_5_BITS;
  633. break;
  634. case CS6: mr1 |= MPC52xx_PSC_MODE_6_BITS;
  635. break;
  636. case CS7: mr1 |= MPC52xx_PSC_MODE_7_BITS;
  637. break;
  638. case CS8:
  639. default: mr1 |= MPC52xx_PSC_MODE_8_BITS;
  640. }
  641. if (new->c_cflag & PARENB) {
  642. mr1 |= (new->c_cflag & PARODD) ?
  643. MPC52xx_PSC_MODE_PARODD : MPC52xx_PSC_MODE_PAREVEN;
  644. } else
  645. mr1 |= MPC52xx_PSC_MODE_PARNONE;
  646. mr2 = 0;
  647. if (new->c_cflag & CSTOPB)
  648. mr2 |= MPC52xx_PSC_MODE_TWO_STOP;
  649. else
  650. mr2 |= ((new->c_cflag & CSIZE) == CS5) ?
  651. MPC52xx_PSC_MODE_ONE_STOP_5_BITS :
  652. MPC52xx_PSC_MODE_ONE_STOP;
  653. if (new->c_cflag & CRTSCTS) {
  654. mr1 |= MPC52xx_PSC_MODE_RXRTS;
  655. mr2 |= MPC52xx_PSC_MODE_TXCTS;
  656. }
  657. /* Get the lock */
  658. spin_lock_irqsave(&port->lock, flags);
  659. /* Do our best to flush TX & RX, so we don't lose anything */
  660. /* But we don't wait indefinitely ! */
  661. j = 5000000; /* Maximum wait */
  662. /* FIXME Can't receive chars since set_termios might be called at early
  663. * boot for the console, all stuff is not yet ready to receive at that
  664. * time and that just makes the kernel oops */
  665. /* while (j-- && mpc52xx_uart_int_rx_chars(port)); */
  666. while (!mpc52xx_uart_tx_empty(port) && --j)
  667. udelay(1);
  668. if (!j)
  669. printk(KERN_ERR "mpc52xx_uart.c: "
  670. "Unable to flush RX & TX fifos in-time in set_termios."
  671. "Some chars may have been lost.\n");
  672. /* Reset the TX & RX */
  673. out_8(&psc->command, MPC52xx_PSC_RST_RX);
  674. out_8(&psc->command, MPC52xx_PSC_RST_TX);
  675. /* Send new mode settings */
  676. out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1);
  677. out_8(&psc->mode, mr1);
  678. out_8(&psc->mode, mr2);
  679. baud = psc_ops->set_baudrate(port, new, old);
  680. /* Update the per-port timeout */
  681. uart_update_timeout(port, new->c_cflag, baud);
  682. if (UART_ENABLE_MS(port, new->c_cflag))
  683. mpc52xx_uart_enable_ms(port);
  684. /* Reenable TX & RX */
  685. out_8(&psc->command, MPC52xx_PSC_TX_ENABLE);
  686. out_8(&psc->command, MPC52xx_PSC_RX_ENABLE);
  687. /* We're all set, release the lock */
  688. spin_unlock_irqrestore(&port->lock, flags);
  689. }
  690. static const char *
  691. mpc52xx_uart_type(struct uart_port *port)
  692. {
  693. return port->type == PORT_MPC52xx ? "MPC52xx PSC" : NULL;
  694. }
  695. static void
  696. mpc52xx_uart_release_port(struct uart_port *port)
  697. {
  698. /* remapped by us ? */
  699. if (port->flags & UPF_IOREMAP) {
  700. iounmap(port->membase);
  701. port->membase = NULL;
  702. }
  703. release_mem_region(port->mapbase, sizeof(struct mpc52xx_psc));
  704. }
  705. static int
  706. mpc52xx_uart_request_port(struct uart_port *port)
  707. {
  708. int err;
  709. if (port->flags & UPF_IOREMAP) /* Need to remap ? */
  710. port->membase = ioremap(port->mapbase,
  711. sizeof(struct mpc52xx_psc));
  712. if (!port->membase)
  713. return -EINVAL;
  714. err = request_mem_region(port->mapbase, sizeof(struct mpc52xx_psc),
  715. "mpc52xx_psc_uart") != NULL ? 0 : -EBUSY;
  716. if (err && (port->flags & UPF_IOREMAP)) {
  717. iounmap(port->membase);
  718. port->membase = NULL;
  719. }
  720. return err;
  721. }
  722. static void
  723. mpc52xx_uart_config_port(struct uart_port *port, int flags)
  724. {
  725. if ((flags & UART_CONFIG_TYPE)
  726. && (mpc52xx_uart_request_port(port) == 0))
  727. port->type = PORT_MPC52xx;
  728. }
  729. static int
  730. mpc52xx_uart_verify_port(struct uart_port *port, struct serial_struct *ser)
  731. {
  732. if (ser->type != PORT_UNKNOWN && ser->type != PORT_MPC52xx)
  733. return -EINVAL;
  734. if ((ser->irq != port->irq) ||
  735. (ser->io_type != UPIO_MEM) ||
  736. (ser->baud_base != port->uartclk) ||
  737. (ser->iomem_base != (void *)port->mapbase) ||
  738. (ser->hub6 != 0))
  739. return -EINVAL;
  740. return 0;
  741. }
  742. static struct uart_ops mpc52xx_uart_ops = {
  743. .tx_empty = mpc52xx_uart_tx_empty,
  744. .set_mctrl = mpc52xx_uart_set_mctrl,
  745. .get_mctrl = mpc52xx_uart_get_mctrl,
  746. .stop_tx = mpc52xx_uart_stop_tx,
  747. .start_tx = mpc52xx_uart_start_tx,
  748. .send_xchar = mpc52xx_uart_send_xchar,
  749. .stop_rx = mpc52xx_uart_stop_rx,
  750. .enable_ms = mpc52xx_uart_enable_ms,
  751. .break_ctl = mpc52xx_uart_break_ctl,
  752. .startup = mpc52xx_uart_startup,
  753. .shutdown = mpc52xx_uart_shutdown,
  754. .set_termios = mpc52xx_uart_set_termios,
  755. /* .pm = mpc52xx_uart_pm, Not supported yet */
  756. /* .set_wake = mpc52xx_uart_set_wake, Not supported yet */
  757. .type = mpc52xx_uart_type,
  758. .release_port = mpc52xx_uart_release_port,
  759. .request_port = mpc52xx_uart_request_port,
  760. .config_port = mpc52xx_uart_config_port,
  761. .verify_port = mpc52xx_uart_verify_port
  762. };
  763. /* ======================================================================== */
  764. /* Interrupt handling */
  765. /* ======================================================================== */
  766. static inline int
  767. mpc52xx_uart_int_rx_chars(struct uart_port *port)
  768. {
  769. struct tty_struct *tty = port->state->port.tty;
  770. unsigned char ch, flag;
  771. unsigned short status;
  772. /* While we can read, do so ! */
  773. while (psc_ops->raw_rx_rdy(port)) {
  774. /* Get the char */
  775. ch = psc_ops->read_char(port);
  776. /* Handle sysreq char */
  777. #ifdef SUPPORT_SYSRQ
  778. if (uart_handle_sysrq_char(port, ch)) {
  779. port->sysrq = 0;
  780. continue;
  781. }
  782. #endif
  783. /* Store it */
  784. flag = TTY_NORMAL;
  785. port->icount.rx++;
  786. status = in_be16(&PSC(port)->mpc52xx_psc_status);
  787. if (status & (MPC52xx_PSC_SR_PE |
  788. MPC52xx_PSC_SR_FE |
  789. MPC52xx_PSC_SR_RB)) {
  790. if (status & MPC52xx_PSC_SR_RB) {
  791. flag = TTY_BREAK;
  792. uart_handle_break(port);
  793. port->icount.brk++;
  794. } else if (status & MPC52xx_PSC_SR_PE) {
  795. flag = TTY_PARITY;
  796. port->icount.parity++;
  797. }
  798. else if (status & MPC52xx_PSC_SR_FE) {
  799. flag = TTY_FRAME;
  800. port->icount.frame++;
  801. }
  802. /* Clear error condition */
  803. out_8(&PSC(port)->command, MPC52xx_PSC_RST_ERR_STAT);
  804. }
  805. tty_insert_flip_char(tty, ch, flag);
  806. if (status & MPC52xx_PSC_SR_OE) {
  807. /*
  808. * Overrun is special, since it's
  809. * reported immediately, and doesn't
  810. * affect the current character
  811. */
  812. tty_insert_flip_char(tty, 0, TTY_OVERRUN);
  813. port->icount.overrun++;
  814. }
  815. }
  816. spin_unlock(&port->lock);
  817. tty_flip_buffer_push(tty);
  818. spin_lock(&port->lock);
  819. return psc_ops->raw_rx_rdy(port);
  820. }
  821. static inline int
  822. mpc52xx_uart_int_tx_chars(struct uart_port *port)
  823. {
  824. struct circ_buf *xmit = &port->state->xmit;
  825. /* Process out of band chars */
  826. if (port->x_char) {
  827. psc_ops->write_char(port, port->x_char);
  828. port->icount.tx++;
  829. port->x_char = 0;
  830. return 1;
  831. }
  832. /* Nothing to do ? */
  833. if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
  834. mpc52xx_uart_stop_tx(port);
  835. return 0;
  836. }
  837. /* Send chars */
  838. while (psc_ops->raw_tx_rdy(port)) {
  839. psc_ops->write_char(port, xmit->buf[xmit->tail]);
  840. xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
  841. port->icount.tx++;
  842. if (uart_circ_empty(xmit))
  843. break;
  844. }
  845. /* Wake up */
  846. if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
  847. uart_write_wakeup(port);
  848. /* Maybe we're done after all */
  849. if (uart_circ_empty(xmit)) {
  850. mpc52xx_uart_stop_tx(port);
  851. return 0;
  852. }
  853. return 1;
  854. }
  855. static irqreturn_t
  856. mpc5xxx_uart_process_int(struct uart_port *port)
  857. {
  858. unsigned long pass = ISR_PASS_LIMIT;
  859. unsigned int keepgoing;
  860. u8 status;
  861. /* While we have stuff to do, we continue */
  862. do {
  863. /* If we don't find anything to do, we stop */
  864. keepgoing = 0;
  865. psc_ops->rx_clr_irq(port);
  866. if (psc_ops->rx_rdy(port))
  867. keepgoing |= mpc52xx_uart_int_rx_chars(port);
  868. psc_ops->tx_clr_irq(port);
  869. if (psc_ops->tx_rdy(port))
  870. keepgoing |= mpc52xx_uart_int_tx_chars(port);
  871. status = in_8(&PSC(port)->mpc52xx_psc_ipcr);
  872. if (status & MPC52xx_PSC_D_DCD)
  873. uart_handle_dcd_change(port, !(status & MPC52xx_PSC_DCD));
  874. if (status & MPC52xx_PSC_D_CTS)
  875. uart_handle_cts_change(port, !(status & MPC52xx_PSC_CTS));
  876. /* Limit number of iteration */
  877. if (!(--pass))
  878. keepgoing = 0;
  879. } while (keepgoing);
  880. return IRQ_HANDLED;
  881. }
  882. static irqreturn_t
  883. mpc52xx_uart_int(int irq, void *dev_id)
  884. {
  885. struct uart_port *port = dev_id;
  886. irqreturn_t ret;
  887. spin_lock(&port->lock);
  888. ret = psc_ops->handle_irq(port);
  889. spin_unlock(&port->lock);
  890. return ret;
  891. }
  892. /* ======================================================================== */
  893. /* Console ( if applicable ) */
  894. /* ======================================================================== */
  895. #ifdef CONFIG_SERIAL_MPC52xx_CONSOLE
  896. static void __init
  897. mpc52xx_console_get_options(struct uart_port *port,
  898. int *baud, int *parity, int *bits, int *flow)
  899. {
  900. struct mpc52xx_psc __iomem *psc = PSC(port);
  901. unsigned char mr1;
  902. pr_debug("mpc52xx_console_get_options(port=%p)\n", port);
  903. /* Read the mode registers */
  904. out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1);
  905. mr1 = in_8(&psc->mode);
  906. /* CT{U,L}R are write-only ! */
  907. *baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD;
  908. /* Parse them */
  909. switch (mr1 & MPC52xx_PSC_MODE_BITS_MASK) {
  910. case MPC52xx_PSC_MODE_5_BITS:
  911. *bits = 5;
  912. break;
  913. case MPC52xx_PSC_MODE_6_BITS:
  914. *bits = 6;
  915. break;
  916. case MPC52xx_PSC_MODE_7_BITS:
  917. *bits = 7;
  918. break;
  919. case MPC52xx_PSC_MODE_8_BITS:
  920. default:
  921. *bits = 8;
  922. }
  923. if (mr1 & MPC52xx_PSC_MODE_PARNONE)
  924. *parity = 'n';
  925. else
  926. *parity = mr1 & MPC52xx_PSC_MODE_PARODD ? 'o' : 'e';
  927. }
  928. static void
  929. mpc52xx_console_write(struct console *co, const char *s, unsigned int count)
  930. {
  931. struct uart_port *port = &mpc52xx_uart_ports[co->index];
  932. unsigned int i, j;
  933. /* Disable interrupts */
  934. psc_ops->cw_disable_ints(port);
  935. /* Wait the TX buffer to be empty */
  936. j = 5000000; /* Maximum wait */
  937. while (!mpc52xx_uart_tx_empty(port) && --j)
  938. udelay(1);
  939. /* Write all the chars */
  940. for (i = 0; i < count; i++, s++) {
  941. /* Line return handling */
  942. if (*s == '\n')
  943. psc_ops->write_char(port, '\r');
  944. /* Send the char */
  945. psc_ops->write_char(port, *s);
  946. /* Wait the TX buffer to be empty */
  947. j = 20000; /* Maximum wait */
  948. while (!mpc52xx_uart_tx_empty(port) && --j)
  949. udelay(1);
  950. }
  951. /* Restore interrupt state */
  952. psc_ops->cw_restore_ints(port);
  953. }
  954. static int __init
  955. mpc52xx_console_setup(struct console *co, char *options)
  956. {
  957. struct uart_port *port = &mpc52xx_uart_ports[co->index];
  958. struct device_node *np = mpc52xx_uart_nodes[co->index];
  959. unsigned int uartclk;
  960. struct resource res;
  961. int ret;
  962. int baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD;
  963. int bits = 8;
  964. int parity = 'n';
  965. int flow = 'n';
  966. pr_debug("mpc52xx_console_setup co=%p, co->index=%i, options=%s\n",
  967. co, co->index, options);
  968. if ((co->index < 0) || (co->index >= MPC52xx_PSC_MAXNUM)) {
  969. pr_debug("PSC%x out of range\n", co->index);
  970. return -EINVAL;
  971. }
  972. if (!np) {
  973. pr_debug("PSC%x not found in device tree\n", co->index);
  974. return -EINVAL;
  975. }
  976. pr_debug("Console on ttyPSC%x is %s\n",
  977. co->index, mpc52xx_uart_nodes[co->index]->full_name);
  978. /* Fetch register locations */
  979. ret = of_address_to_resource(np, 0, &res);
  980. if (ret) {
  981. pr_debug("Could not get resources for PSC%x\n", co->index);
  982. return ret;
  983. }
  984. uartclk = mpc5xxx_get_bus_frequency(np);
  985. if (uartclk == 0) {
  986. pr_debug("Could not find uart clock frequency!\n");
  987. return -EINVAL;
  988. }
  989. /* Basic port init. Needed since we use some uart_??? func before
  990. * real init for early access */
  991. spin_lock_init(&port->lock);
  992. port->uartclk = uartclk;
  993. port->ops = &mpc52xx_uart_ops;
  994. port->mapbase = res.start;
  995. port->membase = ioremap(res.start, sizeof(struct mpc52xx_psc));
  996. port->irq = irq_of_parse_and_map(np, 0);
  997. if (port->membase == NULL)
  998. return -EINVAL;
  999. pr_debug("mpc52xx-psc uart at %p, mapped to %p, irq=%x, freq=%i\n",
  1000. (void *)port->mapbase, port->membase,
  1001. port->irq, port->uartclk);
  1002. /* Setup the port parameters accoding to options */
  1003. if (options)
  1004. uart_parse_options(options, &baud, &parity, &bits, &flow);
  1005. else
  1006. mpc52xx_console_get_options(port, &baud, &parity, &bits, &flow);
  1007. pr_debug("Setting console parameters: %i %i%c1 flow=%c\n",
  1008. baud, bits, parity, flow);
  1009. return uart_set_options(port, co, baud, parity, bits, flow);
  1010. }
  1011. static struct uart_driver mpc52xx_uart_driver;
  1012. static struct console mpc52xx_console = {
  1013. .name = "ttyPSC",
  1014. .write = mpc52xx_console_write,
  1015. .device = uart_console_device,
  1016. .setup = mpc52xx_console_setup,
  1017. .flags = CON_PRINTBUFFER,
  1018. .index = -1, /* Specified on the cmdline (e.g. console=ttyPSC0) */
  1019. .data = &mpc52xx_uart_driver,
  1020. };
  1021. static int __init
  1022. mpc52xx_console_init(void)
  1023. {
  1024. mpc52xx_uart_of_enumerate();
  1025. register_console(&mpc52xx_console);
  1026. return 0;
  1027. }
  1028. console_initcall(mpc52xx_console_init);
  1029. #define MPC52xx_PSC_CONSOLE &mpc52xx_console
  1030. #else
  1031. #define MPC52xx_PSC_CONSOLE NULL
  1032. #endif
  1033. /* ======================================================================== */
  1034. /* UART Driver */
  1035. /* ======================================================================== */
  1036. static struct uart_driver mpc52xx_uart_driver = {
  1037. .driver_name = "mpc52xx_psc_uart",
  1038. .dev_name = "ttyPSC",
  1039. .major = SERIAL_PSC_MAJOR,
  1040. .minor = SERIAL_PSC_MINOR,
  1041. .nr = MPC52xx_PSC_MAXNUM,
  1042. .cons = MPC52xx_PSC_CONSOLE,
  1043. };
  1044. /* ======================================================================== */
  1045. /* OF Platform Driver */
  1046. /* ======================================================================== */
  1047. static struct of_device_id mpc52xx_uart_of_match[] = {
  1048. #ifdef CONFIG_PPC_MPC52xx
  1049. { .compatible = "fsl,mpc5200b-psc-uart", .data = &mpc5200b_psc_ops, },
  1050. { .compatible = "fsl,mpc5200-psc-uart", .data = &mpc52xx_psc_ops, },
  1051. /* binding used by old lite5200 device trees: */
  1052. { .compatible = "mpc5200-psc-uart", .data = &mpc52xx_psc_ops, },
  1053. /* binding used by efika: */
  1054. { .compatible = "mpc5200-serial", .data = &mpc52xx_psc_ops, },
  1055. #endif
  1056. #ifdef CONFIG_PPC_MPC512x
  1057. { .compatible = "fsl,mpc5121-psc-uart", .data = &mpc512x_psc_ops, },
  1058. #endif
  1059. {},
  1060. };
  1061. static int __devinit
  1062. mpc52xx_uart_of_probe(struct platform_device *op, const struct of_device_id *match)
  1063. {
  1064. int idx = -1;
  1065. unsigned int uartclk;
  1066. struct uart_port *port = NULL;
  1067. struct resource res;
  1068. int ret;
  1069. dev_dbg(&op->dev, "mpc52xx_uart_probe(op=%p, match=%p)\n", op, match);
  1070. /* Check validity & presence */
  1071. for (idx = 0; idx < MPC52xx_PSC_MAXNUM; idx++)
  1072. if (mpc52xx_uart_nodes[idx] == op->dev.of_node)
  1073. break;
  1074. if (idx >= MPC52xx_PSC_MAXNUM)
  1075. return -EINVAL;
  1076. pr_debug("Found %s assigned to ttyPSC%x\n",
  1077. mpc52xx_uart_nodes[idx]->full_name, idx);
  1078. /* set the uart clock to the input clock of the psc, the different
  1079. * prescalers are taken into account in the set_baudrate() methods
  1080. * of the respective chip */
  1081. uartclk = mpc5xxx_get_bus_frequency(op->dev.of_node);
  1082. if (uartclk == 0) {
  1083. dev_dbg(&op->dev, "Could not find uart clock frequency!\n");
  1084. return -EINVAL;
  1085. }
  1086. /* Init the port structure */
  1087. port = &mpc52xx_uart_ports[idx];
  1088. spin_lock_init(&port->lock);
  1089. port->uartclk = uartclk;
  1090. port->fifosize = 512;
  1091. port->iotype = UPIO_MEM;
  1092. port->flags = UPF_BOOT_AUTOCONF |
  1093. (uart_console(port) ? 0 : UPF_IOREMAP);
  1094. port->line = idx;
  1095. port->ops = &mpc52xx_uart_ops;
  1096. port->dev = &op->dev;
  1097. /* Search for IRQ and mapbase */
  1098. ret = of_address_to_resource(op->dev.of_node, 0, &res);
  1099. if (ret)
  1100. return ret;
  1101. port->mapbase = res.start;
  1102. if (!port->mapbase) {
  1103. dev_dbg(&op->dev, "Could not allocate resources for PSC\n");
  1104. return -EINVAL;
  1105. }
  1106. psc_ops->get_irq(port, op->dev.of_node);
  1107. if (port->irq == NO_IRQ) {
  1108. dev_dbg(&op->dev, "Could not get irq\n");
  1109. return -EINVAL;
  1110. }
  1111. dev_dbg(&op->dev, "mpc52xx-psc uart at %p, irq=%x, freq=%i\n",
  1112. (void *)port->mapbase, port->irq, port->uartclk);
  1113. /* Add the port to the uart sub-system */
  1114. ret = uart_add_one_port(&mpc52xx_uart_driver, port);
  1115. if (ret)
  1116. return ret;
  1117. dev_set_drvdata(&op->dev, (void *)port);
  1118. return 0;
  1119. }
  1120. static int
  1121. mpc52xx_uart_of_remove(struct platform_device *op)
  1122. {
  1123. struct uart_port *port = dev_get_drvdata(&op->dev);
  1124. dev_set_drvdata(&op->dev, NULL);
  1125. if (port)
  1126. uart_remove_one_port(&mpc52xx_uart_driver, port);
  1127. return 0;
  1128. }
  1129. #ifdef CONFIG_PM
  1130. static int
  1131. mpc52xx_uart_of_suspend(struct platform_device *op, pm_message_t state)
  1132. {
  1133. struct uart_port *port = (struct uart_port *) dev_get_drvdata(&op->dev);
  1134. if (port)
  1135. uart_suspend_port(&mpc52xx_uart_driver, port);
  1136. return 0;
  1137. }
  1138. static int
  1139. mpc52xx_uart_of_resume(struct platform_device *op)
  1140. {
  1141. struct uart_port *port = (struct uart_port *) dev_get_drvdata(&op->dev);
  1142. if (port)
  1143. uart_resume_port(&mpc52xx_uart_driver, port);
  1144. return 0;
  1145. }
  1146. #endif
  1147. static void
  1148. mpc52xx_uart_of_assign(struct device_node *np)
  1149. {
  1150. int i;
  1151. /* Find the first free PSC number */
  1152. for (i = 0; i < MPC52xx_PSC_MAXNUM; i++) {
  1153. if (mpc52xx_uart_nodes[i] == NULL) {
  1154. of_node_get(np);
  1155. mpc52xx_uart_nodes[i] = np;
  1156. return;
  1157. }
  1158. }
  1159. }
  1160. static void
  1161. mpc52xx_uart_of_enumerate(void)
  1162. {
  1163. static int enum_done;
  1164. struct device_node *np;
  1165. const struct of_device_id *match;
  1166. int i;
  1167. if (enum_done)
  1168. return;
  1169. /* Assign index to each PSC in device tree */
  1170. for_each_matching_node(np, mpc52xx_uart_of_match) {
  1171. match = of_match_node(mpc52xx_uart_of_match, np);
  1172. psc_ops = match->data;
  1173. mpc52xx_uart_of_assign(np);
  1174. }
  1175. enum_done = 1;
  1176. for (i = 0; i < MPC52xx_PSC_MAXNUM; i++) {
  1177. if (mpc52xx_uart_nodes[i])
  1178. pr_debug("%s assigned to ttyPSC%x\n",
  1179. mpc52xx_uart_nodes[i]->full_name, i);
  1180. }
  1181. }
  1182. MODULE_DEVICE_TABLE(of, mpc52xx_uart_of_match);
  1183. static struct of_platform_driver mpc52xx_uart_of_driver = {
  1184. .probe = mpc52xx_uart_of_probe,
  1185. .remove = mpc52xx_uart_of_remove,
  1186. #ifdef CONFIG_PM
  1187. .suspend = mpc52xx_uart_of_suspend,
  1188. .resume = mpc52xx_uart_of_resume,
  1189. #endif
  1190. .driver = {
  1191. .name = "mpc52xx-psc-uart",
  1192. .owner = THIS_MODULE,
  1193. .of_match_table = mpc52xx_uart_of_match,
  1194. },
  1195. };
  1196. /* ======================================================================== */
  1197. /* Module */
  1198. /* ======================================================================== */
  1199. static int __init
  1200. mpc52xx_uart_init(void)
  1201. {
  1202. int ret;
  1203. printk(KERN_INFO "Serial: MPC52xx PSC UART driver\n");
  1204. ret = uart_register_driver(&mpc52xx_uart_driver);
  1205. if (ret) {
  1206. printk(KERN_ERR "%s: uart_register_driver failed (%i)\n",
  1207. __FILE__, ret);
  1208. return ret;
  1209. }
  1210. mpc52xx_uart_of_enumerate();
  1211. /*
  1212. * Map the PSC FIFO Controller and init if on MPC512x.
  1213. */
  1214. if (psc_ops && psc_ops->fifoc_init) {
  1215. ret = psc_ops->fifoc_init();
  1216. if (ret)
  1217. return ret;
  1218. }
  1219. ret = of_register_platform_driver(&mpc52xx_uart_of_driver);
  1220. if (ret) {
  1221. printk(KERN_ERR "%s: of_register_platform_driver failed (%i)\n",
  1222. __FILE__, ret);
  1223. uart_unregister_driver(&mpc52xx_uart_driver);
  1224. return ret;
  1225. }
  1226. return 0;
  1227. }
  1228. static void __exit
  1229. mpc52xx_uart_exit(void)
  1230. {
  1231. if (psc_ops->fifoc_uninit)
  1232. psc_ops->fifoc_uninit();
  1233. of_unregister_platform_driver(&mpc52xx_uart_of_driver);
  1234. uart_unregister_driver(&mpc52xx_uart_driver);
  1235. }
  1236. module_init(mpc52xx_uart_init);
  1237. module_exit(mpc52xx_uart_exit);
  1238. MODULE_AUTHOR("Sylvain Munaut <tnt@246tNt.com>");
  1239. MODULE_DESCRIPTION("Freescale MPC52xx PSC UART");
  1240. MODULE_LICENSE("GPL");