8250_dw.c 22 KB

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  1. // SPDX-License-Identifier: GPL-2.0+
  2. /*
  3. * Synopsys DesignWare 8250 driver.
  4. *
  5. * Copyright 2011 Picochip, Jamie Iles.
  6. * Copyright 2013 Intel Corporation
  7. *
  8. * The Synopsys DesignWare 8250 has an extra feature whereby it detects if the
  9. * LCR is written whilst busy. If it is, then a busy detect interrupt is
  10. * raised, the LCR needs to be rewritten and the uart status register read.
  11. */
  12. #include <linux/acpi.h>
  13. #include <linux/clk.h>
  14. #include <linux/delay.h>
  15. #include <linux/device.h>
  16. #include <linux/io.h>
  17. #include <linux/mod_devicetable.h>
  18. #include <linux/module.h>
  19. #include <linux/notifier.h>
  20. #include <linux/of.h>
  21. #include <linux/platform_device.h>
  22. #include <linux/pm_runtime.h>
  23. #include <linux/property.h>
  24. #include <linux/reset.h>
  25. #include <linux/slab.h>
  26. #include <linux/workqueue.h>
  27. #include <asm/byteorder.h>
  28. #include <linux/serial_8250.h>
  29. #include <linux/serial_reg.h>
  30. #include "8250_dwlib.h"
  31. /* Offsets for the DesignWare specific registers */
  32. #define DW_UART_USR 0x1f /* UART Status Register */
  33. #define DW_UART_DMASA 0xa8 /* DMA Software Ack */
  34. #define OCTEON_UART_USR 0x27 /* UART Status Register */
  35. #define RZN1_UART_TDMACR 0x10c /* DMA Control Register Transmit Mode */
  36. #define RZN1_UART_RDMACR 0x110 /* DMA Control Register Receive Mode */
  37. /* DesignWare specific register fields */
  38. #define DW_UART_MCR_SIRE BIT(6)
  39. /* Renesas specific register fields */
  40. #define RZN1_UART_xDMACR_DMA_EN BIT(0)
  41. #define RZN1_UART_xDMACR_1_WORD_BURST (0 << 1)
  42. #define RZN1_UART_xDMACR_4_WORD_BURST (1 << 1)
  43. #define RZN1_UART_xDMACR_8_WORD_BURST (2 << 1)
  44. #define RZN1_UART_xDMACR_BLK_SZ(x) ((x) << 3)
  45. /* Quirks */
  46. #define DW_UART_QUIRK_OCTEON BIT(0)
  47. #define DW_UART_QUIRK_ARMADA_38X BIT(1)
  48. #define DW_UART_QUIRK_SKIP_SET_RATE BIT(2)
  49. #define DW_UART_QUIRK_IS_DMA_FC BIT(3)
  50. static inline struct dw8250_data *clk_to_dw8250_data(struct notifier_block *nb)
  51. {
  52. return container_of(nb, struct dw8250_data, clk_notifier);
  53. }
  54. static inline struct dw8250_data *work_to_dw8250_data(struct work_struct *work)
  55. {
  56. return container_of(work, struct dw8250_data, clk_work);
  57. }
  58. static inline int dw8250_modify_msr(struct uart_port *p, int offset, int value)
  59. {
  60. struct dw8250_data *d = to_dw8250_data(p->private_data);
  61. /* Override any modem control signals if needed */
  62. if (offset == UART_MSR) {
  63. value |= d->msr_mask_on;
  64. value &= ~d->msr_mask_off;
  65. }
  66. return value;
  67. }
  68. static void dw8250_force_idle(struct uart_port *p)
  69. {
  70. struct uart_8250_port *up = up_to_u8250p(p);
  71. unsigned int lsr;
  72. serial8250_clear_and_reinit_fifos(up);
  73. /*
  74. * With PSLVERR_RESP_EN parameter set to 1, the device generates an
  75. * error response when an attempt to read an empty RBR with FIFO
  76. * enabled.
  77. */
  78. if (up->fcr & UART_FCR_ENABLE_FIFO) {
  79. lsr = p->serial_in(p, UART_LSR);
  80. if (!(lsr & UART_LSR_DR))
  81. return;
  82. }
  83. (void)p->serial_in(p, UART_RX);
  84. }
  85. static void dw8250_check_lcr(struct uart_port *p, int value)
  86. {
  87. void __iomem *offset = p->membase + (UART_LCR << p->regshift);
  88. int tries = 1000;
  89. /* Make sure LCR write wasn't ignored */
  90. while (tries--) {
  91. unsigned int lcr = p->serial_in(p, UART_LCR);
  92. if ((value & ~UART_LCR_SPAR) == (lcr & ~UART_LCR_SPAR))
  93. return;
  94. dw8250_force_idle(p);
  95. #ifdef CONFIG_64BIT
  96. if (p->type == PORT_OCTEON)
  97. __raw_writeq(value & 0xff, offset);
  98. else
  99. #endif
  100. if (p->iotype == UPIO_MEM32)
  101. writel(value, offset);
  102. else if (p->iotype == UPIO_MEM32BE)
  103. iowrite32be(value, offset);
  104. else
  105. writeb(value, offset);
  106. }
  107. /*
  108. * FIXME: this deadlocks if port->lock is already held
  109. * dev_err(p->dev, "Couldn't set LCR to %d\n", value);
  110. */
  111. }
  112. /* Returns once the transmitter is empty or we run out of retries */
  113. static void dw8250_tx_wait_empty(struct uart_port *p)
  114. {
  115. struct uart_8250_port *up = up_to_u8250p(p);
  116. unsigned int tries = 20000;
  117. unsigned int delay_threshold = tries - 1000;
  118. unsigned int lsr;
  119. while (tries--) {
  120. lsr = readb (p->membase + (UART_LSR << p->regshift));
  121. up->lsr_saved_flags |= lsr & up->lsr_save_mask;
  122. if (lsr & UART_LSR_TEMT)
  123. break;
  124. /* The device is first given a chance to empty without delay,
  125. * to avoid slowdowns at high bitrates. If after 1000 tries
  126. * the buffer has still not emptied, allow more time for low-
  127. * speed links. */
  128. if (tries < delay_threshold)
  129. udelay (1);
  130. }
  131. }
  132. static void dw8250_serial_out(struct uart_port *p, int offset, int value)
  133. {
  134. struct dw8250_data *d = to_dw8250_data(p->private_data);
  135. writeb(value, p->membase + (offset << p->regshift));
  136. if (offset == UART_LCR && !d->uart_16550_compatible)
  137. dw8250_check_lcr(p, value);
  138. }
  139. static void dw8250_serial_out38x(struct uart_port *p, int offset, int value)
  140. {
  141. /* Allow the TX to drain before we reconfigure */
  142. if (offset == UART_LCR)
  143. dw8250_tx_wait_empty(p);
  144. dw8250_serial_out(p, offset, value);
  145. }
  146. static unsigned int dw8250_serial_in(struct uart_port *p, int offset)
  147. {
  148. unsigned int value = readb(p->membase + (offset << p->regshift));
  149. return dw8250_modify_msr(p, offset, value);
  150. }
  151. #ifdef CONFIG_64BIT
  152. static unsigned int dw8250_serial_inq(struct uart_port *p, int offset)
  153. {
  154. unsigned int value;
  155. value = (u8)__raw_readq(p->membase + (offset << p->regshift));
  156. return dw8250_modify_msr(p, offset, value);
  157. }
  158. static void dw8250_serial_outq(struct uart_port *p, int offset, int value)
  159. {
  160. struct dw8250_data *d = to_dw8250_data(p->private_data);
  161. value &= 0xff;
  162. __raw_writeq(value, p->membase + (offset << p->regshift));
  163. /* Read back to ensure register write ordering. */
  164. __raw_readq(p->membase + (UART_LCR << p->regshift));
  165. if (offset == UART_LCR && !d->uart_16550_compatible)
  166. dw8250_check_lcr(p, value);
  167. }
  168. #endif /* CONFIG_64BIT */
  169. static void dw8250_serial_out32(struct uart_port *p, int offset, int value)
  170. {
  171. struct dw8250_data *d = to_dw8250_data(p->private_data);
  172. writel(value, p->membase + (offset << p->regshift));
  173. if (offset == UART_LCR && !d->uart_16550_compatible)
  174. dw8250_check_lcr(p, value);
  175. }
  176. static unsigned int dw8250_serial_in32(struct uart_port *p, int offset)
  177. {
  178. unsigned int value = readl(p->membase + (offset << p->regshift));
  179. return dw8250_modify_msr(p, offset, value);
  180. }
  181. static void dw8250_serial_out32be(struct uart_port *p, int offset, int value)
  182. {
  183. struct dw8250_data *d = to_dw8250_data(p->private_data);
  184. iowrite32be(value, p->membase + (offset << p->regshift));
  185. if (offset == UART_LCR && !d->uart_16550_compatible)
  186. dw8250_check_lcr(p, value);
  187. }
  188. static unsigned int dw8250_serial_in32be(struct uart_port *p, int offset)
  189. {
  190. unsigned int value = ioread32be(p->membase + (offset << p->regshift));
  191. return dw8250_modify_msr(p, offset, value);
  192. }
  193. static int dw8250_handle_irq(struct uart_port *p)
  194. {
  195. struct uart_8250_port *up = up_to_u8250p(p);
  196. struct dw8250_data *d = to_dw8250_data(p->private_data);
  197. unsigned int iir = p->serial_in(p, UART_IIR);
  198. bool rx_timeout = (iir & 0x3f) == UART_IIR_RX_TIMEOUT;
  199. unsigned int quirks = d->pdata->quirks;
  200. unsigned int status;
  201. unsigned long flags;
  202. /*
  203. * There are ways to get Designware-based UARTs into a state where
  204. * they are asserting UART_IIR_RX_TIMEOUT but there is no actual
  205. * data available. If we see such a case then we'll do a bogus
  206. * read. If we don't do this then the "RX TIMEOUT" interrupt will
  207. * fire forever.
  208. *
  209. * This problem has only been observed so far when not in DMA mode
  210. * so we limit the workaround only to non-DMA mode.
  211. */
  212. if (!up->dma && rx_timeout) {
  213. spin_lock_irqsave(&p->lock, flags);
  214. status = serial_lsr_in(up);
  215. if (!(status & (UART_LSR_DR | UART_LSR_BI)))
  216. (void) p->serial_in(p, UART_RX);
  217. spin_unlock_irqrestore(&p->lock, flags);
  218. }
  219. /* Manually stop the Rx DMA transfer when acting as flow controller */
  220. if (quirks & DW_UART_QUIRK_IS_DMA_FC && up->dma && up->dma->rx_running && rx_timeout) {
  221. spin_lock_irqsave(&p->lock, flags);
  222. status = serial_lsr_in(up);
  223. spin_unlock_irqrestore(&p->lock, flags);
  224. if (status & (UART_LSR_DR | UART_LSR_BI)) {
  225. dw8250_writel_ext(p, RZN1_UART_RDMACR, 0);
  226. dw8250_writel_ext(p, DW_UART_DMASA, 1);
  227. }
  228. }
  229. if (serial8250_handle_irq(p, iir))
  230. return 1;
  231. if ((iir & UART_IIR_BUSY) == UART_IIR_BUSY) {
  232. /* Clear the USR */
  233. (void)p->serial_in(p, d->pdata->usr_reg);
  234. return 1;
  235. }
  236. return 0;
  237. }
  238. static void dw8250_clk_work_cb(struct work_struct *work)
  239. {
  240. struct dw8250_data *d = work_to_dw8250_data(work);
  241. struct uart_8250_port *up;
  242. unsigned long rate;
  243. rate = clk_get_rate(d->clk);
  244. if (rate <= 0)
  245. return;
  246. up = serial8250_get_port(d->data.line);
  247. serial8250_update_uartclk(&up->port, rate);
  248. }
  249. static int dw8250_clk_notifier_cb(struct notifier_block *nb,
  250. unsigned long event, void *data)
  251. {
  252. struct dw8250_data *d = clk_to_dw8250_data(nb);
  253. /*
  254. * We have no choice but to defer the uartclk update due to two
  255. * deadlocks. First one is caused by a recursive mutex lock which
  256. * happens when clk_set_rate() is called from dw8250_set_termios().
  257. * Second deadlock is more tricky and is caused by an inverted order of
  258. * the clk and tty-port mutexes lock. It happens if clock rate change
  259. * is requested asynchronously while set_termios() is executed between
  260. * tty-port mutex lock and clk_set_rate() function invocation and
  261. * vise-versa. Anyway if we didn't have the reference clock alteration
  262. * in the dw8250_set_termios() method we wouldn't have needed this
  263. * deferred event handling complication.
  264. */
  265. if (event == POST_RATE_CHANGE) {
  266. queue_work(system_unbound_wq, &d->clk_work);
  267. return NOTIFY_OK;
  268. }
  269. return NOTIFY_DONE;
  270. }
  271. static void
  272. dw8250_do_pm(struct uart_port *port, unsigned int state, unsigned int old)
  273. {
  274. if (!state)
  275. pm_runtime_get_sync(port->dev);
  276. serial8250_do_pm(port, state, old);
  277. if (state)
  278. pm_runtime_put_sync_suspend(port->dev);
  279. }
  280. static void dw8250_set_termios(struct uart_port *p, struct ktermios *termios,
  281. const struct ktermios *old)
  282. {
  283. unsigned long newrate = tty_termios_baud_rate(termios) * 16;
  284. struct dw8250_data *d = to_dw8250_data(p->private_data);
  285. long rate;
  286. int ret;
  287. clk_disable_unprepare(d->clk);
  288. rate = clk_round_rate(d->clk, newrate);
  289. if (rate > 0) {
  290. /*
  291. * Note that any clock-notifer worker will block in
  292. * serial8250_update_uartclk() until we are done.
  293. */
  294. ret = clk_set_rate(d->clk, newrate);
  295. if (!ret)
  296. p->uartclk = rate;
  297. }
  298. clk_prepare_enable(d->clk);
  299. dw8250_do_set_termios(p, termios, old);
  300. }
  301. static void dw8250_set_ldisc(struct uart_port *p, struct ktermios *termios)
  302. {
  303. struct uart_8250_port *up = up_to_u8250p(p);
  304. unsigned int mcr = p->serial_in(p, UART_MCR);
  305. if (up->capabilities & UART_CAP_IRDA) {
  306. if (termios->c_line == N_IRDA)
  307. mcr |= DW_UART_MCR_SIRE;
  308. else
  309. mcr &= ~DW_UART_MCR_SIRE;
  310. p->serial_out(p, UART_MCR, mcr);
  311. }
  312. serial8250_do_set_ldisc(p, termios);
  313. }
  314. /*
  315. * dw8250_fallback_dma_filter will prevent the UART from getting just any free
  316. * channel on platforms that have DMA engines, but don't have any channels
  317. * assigned to the UART.
  318. *
  319. * REVISIT: This is a work around for limitation in the DMA Engine API. Once the
  320. * core problem is fixed, this function is no longer needed.
  321. */
  322. static bool dw8250_fallback_dma_filter(struct dma_chan *chan, void *param)
  323. {
  324. return false;
  325. }
  326. static bool dw8250_idma_filter(struct dma_chan *chan, void *param)
  327. {
  328. return param == chan->device->dev;
  329. }
  330. static u32 dw8250_rzn1_get_dmacr_burst(int max_burst)
  331. {
  332. if (max_burst >= 8)
  333. return RZN1_UART_xDMACR_8_WORD_BURST;
  334. else if (max_burst >= 4)
  335. return RZN1_UART_xDMACR_4_WORD_BURST;
  336. else
  337. return RZN1_UART_xDMACR_1_WORD_BURST;
  338. }
  339. static void dw8250_prepare_tx_dma(struct uart_8250_port *p)
  340. {
  341. struct uart_port *up = &p->port;
  342. struct uart_8250_dma *dma = p->dma;
  343. u32 val;
  344. dw8250_writel_ext(up, RZN1_UART_TDMACR, 0);
  345. val = dw8250_rzn1_get_dmacr_burst(dma->txconf.dst_maxburst) |
  346. RZN1_UART_xDMACR_BLK_SZ(dma->tx_size) |
  347. RZN1_UART_xDMACR_DMA_EN;
  348. dw8250_writel_ext(up, RZN1_UART_TDMACR, val);
  349. }
  350. static void dw8250_prepare_rx_dma(struct uart_8250_port *p)
  351. {
  352. struct uart_port *up = &p->port;
  353. struct uart_8250_dma *dma = p->dma;
  354. u32 val;
  355. dw8250_writel_ext(up, RZN1_UART_RDMACR, 0);
  356. val = dw8250_rzn1_get_dmacr_burst(dma->rxconf.src_maxburst) |
  357. RZN1_UART_xDMACR_BLK_SZ(dma->rx_size) |
  358. RZN1_UART_xDMACR_DMA_EN;
  359. dw8250_writel_ext(up, RZN1_UART_RDMACR, val);
  360. }
  361. static void dw8250_quirks(struct uart_port *p, struct dw8250_data *data)
  362. {
  363. struct device_node *np = p->dev->of_node;
  364. if (np) {
  365. unsigned int quirks = data->pdata->quirks;
  366. int id;
  367. /* get index of serial line, if found in DT aliases */
  368. id = of_alias_get_id(np, "serial");
  369. if (id >= 0)
  370. p->line = id;
  371. #ifdef CONFIG_64BIT
  372. if (quirks & DW_UART_QUIRK_OCTEON) {
  373. p->serial_in = dw8250_serial_inq;
  374. p->serial_out = dw8250_serial_outq;
  375. p->flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_FIXED_TYPE;
  376. p->type = PORT_OCTEON;
  377. data->skip_autocfg = true;
  378. }
  379. #endif
  380. if (of_device_is_big_endian(np)) {
  381. p->iotype = UPIO_MEM32BE;
  382. p->serial_in = dw8250_serial_in32be;
  383. p->serial_out = dw8250_serial_out32be;
  384. }
  385. if (quirks & DW_UART_QUIRK_ARMADA_38X)
  386. p->serial_out = dw8250_serial_out38x;
  387. if (quirks & DW_UART_QUIRK_SKIP_SET_RATE)
  388. p->set_termios = dw8250_do_set_termios;
  389. if (quirks & DW_UART_QUIRK_IS_DMA_FC) {
  390. data->data.dma.txconf.device_fc = 1;
  391. data->data.dma.rxconf.device_fc = 1;
  392. data->data.dma.prepare_tx_dma = dw8250_prepare_tx_dma;
  393. data->data.dma.prepare_rx_dma = dw8250_prepare_rx_dma;
  394. }
  395. } else if (acpi_dev_present("APMC0D08", NULL, -1)) {
  396. p->iotype = UPIO_MEM32;
  397. p->regshift = 2;
  398. p->serial_in = dw8250_serial_in32;
  399. data->uart_16550_compatible = true;
  400. }
  401. /* Platforms with iDMA 64-bit */
  402. if (platform_get_resource_byname(to_platform_device(p->dev),
  403. IORESOURCE_MEM, "lpss_priv")) {
  404. data->data.dma.rx_param = p->dev->parent;
  405. data->data.dma.tx_param = p->dev->parent;
  406. data->data.dma.fn = dw8250_idma_filter;
  407. }
  408. }
  409. static void dw8250_clk_disable_unprepare(void *data)
  410. {
  411. clk_disable_unprepare(data);
  412. }
  413. static void dw8250_reset_control_assert(void *data)
  414. {
  415. reset_control_assert(data);
  416. }
  417. static int dw8250_probe(struct platform_device *pdev)
  418. {
  419. struct uart_8250_port uart = {}, *up = &uart;
  420. struct uart_port *p = &up->port;
  421. struct device *dev = &pdev->dev;
  422. struct dw8250_data *data;
  423. struct resource *regs;
  424. int irq;
  425. int err;
  426. u32 val;
  427. regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  428. if (!regs)
  429. return dev_err_probe(dev, -EINVAL, "no registers defined\n");
  430. irq = platform_get_irq_optional(pdev, 0);
  431. /* no interrupt -> fall back to polling */
  432. if (irq == -ENXIO)
  433. irq = 0;
  434. if (irq < 0)
  435. return irq;
  436. spin_lock_init(&p->lock);
  437. p->mapbase = regs->start;
  438. p->irq = irq;
  439. p->handle_irq = dw8250_handle_irq;
  440. p->pm = dw8250_do_pm;
  441. p->type = PORT_8250;
  442. p->flags = UPF_SHARE_IRQ | UPF_FIXED_PORT;
  443. p->dev = dev;
  444. p->iotype = UPIO_MEM;
  445. p->serial_in = dw8250_serial_in;
  446. p->serial_out = dw8250_serial_out;
  447. p->set_ldisc = dw8250_set_ldisc;
  448. p->set_termios = dw8250_set_termios;
  449. p->membase = devm_ioremap(dev, regs->start, resource_size(regs));
  450. if (!p->membase)
  451. return -ENOMEM;
  452. data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
  453. if (!data)
  454. return -ENOMEM;
  455. data->data.dma.fn = dw8250_fallback_dma_filter;
  456. data->pdata = device_get_match_data(p->dev);
  457. p->private_data = &data->data;
  458. data->uart_16550_compatible = device_property_read_bool(dev,
  459. "snps,uart-16550-compatible");
  460. err = device_property_read_u32(dev, "reg-shift", &val);
  461. if (!err)
  462. p->regshift = val;
  463. err = device_property_read_u32(dev, "reg-io-width", &val);
  464. if (!err && val == 4) {
  465. p->iotype = UPIO_MEM32;
  466. p->serial_in = dw8250_serial_in32;
  467. p->serial_out = dw8250_serial_out32;
  468. }
  469. if (device_property_read_bool(dev, "dcd-override")) {
  470. /* Always report DCD as active */
  471. data->msr_mask_on |= UART_MSR_DCD;
  472. data->msr_mask_off |= UART_MSR_DDCD;
  473. }
  474. if (device_property_read_bool(dev, "dsr-override")) {
  475. /* Always report DSR as active */
  476. data->msr_mask_on |= UART_MSR_DSR;
  477. data->msr_mask_off |= UART_MSR_DDSR;
  478. }
  479. if (device_property_read_bool(dev, "cts-override")) {
  480. /* Always report CTS as active */
  481. data->msr_mask_on |= UART_MSR_CTS;
  482. data->msr_mask_off |= UART_MSR_DCTS;
  483. }
  484. if (device_property_read_bool(dev, "ri-override")) {
  485. /* Always report Ring indicator as inactive */
  486. data->msr_mask_off |= UART_MSR_RI;
  487. data->msr_mask_off |= UART_MSR_TERI;
  488. }
  489. /* Always ask for fixed clock rate from a property. */
  490. device_property_read_u32(dev, "clock-frequency", &p->uartclk);
  491. /* If there is separate baudclk, get the rate from it. */
  492. data->clk = devm_clk_get_optional(dev, "baudclk");
  493. if (data->clk == NULL)
  494. data->clk = devm_clk_get_optional(dev, NULL);
  495. if (IS_ERR(data->clk))
  496. return PTR_ERR(data->clk);
  497. INIT_WORK(&data->clk_work, dw8250_clk_work_cb);
  498. data->clk_notifier.notifier_call = dw8250_clk_notifier_cb;
  499. err = clk_prepare_enable(data->clk);
  500. if (err)
  501. return dev_err_probe(dev, err, "could not enable optional baudclk\n");
  502. err = devm_add_action_or_reset(dev, dw8250_clk_disable_unprepare, data->clk);
  503. if (err)
  504. return err;
  505. if (data->clk)
  506. p->uartclk = clk_get_rate(data->clk);
  507. /* If no clock rate is defined, fail. */
  508. if (!p->uartclk)
  509. return dev_err_probe(dev, -EINVAL, "clock rate not defined\n");
  510. data->pclk = devm_clk_get_optional(dev, "apb_pclk");
  511. if (IS_ERR(data->pclk))
  512. return PTR_ERR(data->pclk);
  513. err = clk_prepare_enable(data->pclk);
  514. if (err)
  515. return dev_err_probe(dev, err, "could not enable apb_pclk\n");
  516. err = devm_add_action_or_reset(dev, dw8250_clk_disable_unprepare, data->pclk);
  517. if (err)
  518. return err;
  519. data->rst = devm_reset_control_get_optional_exclusive(dev, NULL);
  520. if (IS_ERR(data->rst))
  521. return PTR_ERR(data->rst);
  522. reset_control_deassert(data->rst);
  523. err = devm_add_action_or_reset(dev, dw8250_reset_control_assert, data->rst);
  524. if (err)
  525. return err;
  526. dw8250_quirks(p, data);
  527. /* If the Busy Functionality is not implemented, don't handle it */
  528. if (data->uart_16550_compatible)
  529. p->handle_irq = NULL;
  530. if (!data->skip_autocfg)
  531. dw8250_setup_port(p);
  532. /* If we have a valid fifosize, try hooking up DMA */
  533. if (p->fifosize) {
  534. data->data.dma.rxconf.src_maxburst = p->fifosize / 4;
  535. data->data.dma.txconf.dst_maxburst = p->fifosize / 4;
  536. up->dma = &data->data.dma;
  537. }
  538. data->data.line = serial8250_register_8250_port(up);
  539. if (data->data.line < 0)
  540. return data->data.line;
  541. /*
  542. * Some platforms may provide a reference clock shared between several
  543. * devices. In this case any clock state change must be known to the
  544. * UART port at least post factum.
  545. */
  546. if (data->clk) {
  547. err = clk_notifier_register(data->clk, &data->clk_notifier);
  548. if (err)
  549. return dev_err_probe(dev, err, "Failed to set the clock notifier\n");
  550. queue_work(system_unbound_wq, &data->clk_work);
  551. }
  552. platform_set_drvdata(pdev, data);
  553. pm_runtime_set_active(dev);
  554. pm_runtime_enable(dev);
  555. return 0;
  556. }
  557. static int dw8250_remove(struct platform_device *pdev)
  558. {
  559. struct dw8250_data *data = platform_get_drvdata(pdev);
  560. struct device *dev = &pdev->dev;
  561. pm_runtime_get_sync(dev);
  562. if (data->clk) {
  563. clk_notifier_unregister(data->clk, &data->clk_notifier);
  564. flush_work(&data->clk_work);
  565. }
  566. serial8250_unregister_port(data->data.line);
  567. pm_runtime_disable(dev);
  568. pm_runtime_put_noidle(dev);
  569. return 0;
  570. }
  571. static int dw8250_suspend(struct device *dev)
  572. {
  573. struct dw8250_data *data = dev_get_drvdata(dev);
  574. serial8250_suspend_port(data->data.line);
  575. return 0;
  576. }
  577. static int dw8250_resume(struct device *dev)
  578. {
  579. struct dw8250_data *data = dev_get_drvdata(dev);
  580. serial8250_resume_port(data->data.line);
  581. return 0;
  582. }
  583. static int dw8250_runtime_suspend(struct device *dev)
  584. {
  585. struct dw8250_data *data = dev_get_drvdata(dev);
  586. clk_disable_unprepare(data->clk);
  587. clk_disable_unprepare(data->pclk);
  588. return 0;
  589. }
  590. static int dw8250_runtime_resume(struct device *dev)
  591. {
  592. struct dw8250_data *data = dev_get_drvdata(dev);
  593. clk_prepare_enable(data->pclk);
  594. clk_prepare_enable(data->clk);
  595. return 0;
  596. }
  597. static const struct dev_pm_ops dw8250_pm_ops = {
  598. SYSTEM_SLEEP_PM_OPS(dw8250_suspend, dw8250_resume)
  599. RUNTIME_PM_OPS(dw8250_runtime_suspend, dw8250_runtime_resume, NULL)
  600. };
  601. static const struct dw8250_platform_data dw8250_dw_apb = {
  602. .usr_reg = DW_UART_USR,
  603. };
  604. static const struct dw8250_platform_data dw8250_octeon_3860_data = {
  605. .usr_reg = OCTEON_UART_USR,
  606. .quirks = DW_UART_QUIRK_OCTEON,
  607. };
  608. static const struct dw8250_platform_data dw8250_armada_38x_data = {
  609. .usr_reg = DW_UART_USR,
  610. .quirks = DW_UART_QUIRK_ARMADA_38X,
  611. };
  612. static const struct dw8250_platform_data dw8250_renesas_rzn1_data = {
  613. .usr_reg = DW_UART_USR,
  614. .cpr_val = 0x00012f32,
  615. .quirks = DW_UART_QUIRK_IS_DMA_FC,
  616. };
  617. static const struct dw8250_platform_data dw8250_starfive_jh7100_data = {
  618. .usr_reg = DW_UART_USR,
  619. .quirks = DW_UART_QUIRK_SKIP_SET_RATE,
  620. };
  621. static const struct of_device_id dw8250_of_match[] = {
  622. { .compatible = "snps,dw-apb-uart", .data = &dw8250_dw_apb },
  623. { .compatible = "cavium,octeon-3860-uart", .data = &dw8250_octeon_3860_data },
  624. { .compatible = "marvell,armada-38x-uart", .data = &dw8250_armada_38x_data },
  625. { .compatible = "renesas,rzn1-uart", .data = &dw8250_renesas_rzn1_data },
  626. { .compatible = "starfive,jh7100-uart", .data = &dw8250_starfive_jh7100_data },
  627. { /* Sentinel */ }
  628. };
  629. MODULE_DEVICE_TABLE(of, dw8250_of_match);
  630. static const struct acpi_device_id dw8250_acpi_match[] = {
  631. { "80860F0A", (kernel_ulong_t)&dw8250_dw_apb },
  632. { "8086228A", (kernel_ulong_t)&dw8250_dw_apb },
  633. { "AMD0020", (kernel_ulong_t)&dw8250_dw_apb },
  634. { "AMDI0020", (kernel_ulong_t)&dw8250_dw_apb },
  635. { "AMDI0022", (kernel_ulong_t)&dw8250_dw_apb },
  636. { "APMC0D08", (kernel_ulong_t)&dw8250_dw_apb},
  637. { "BRCM2032", (kernel_ulong_t)&dw8250_dw_apb },
  638. { "HISI0031", (kernel_ulong_t)&dw8250_dw_apb },
  639. { "INT33C4", (kernel_ulong_t)&dw8250_dw_apb },
  640. { "INT33C5", (kernel_ulong_t)&dw8250_dw_apb },
  641. { "INT3434", (kernel_ulong_t)&dw8250_dw_apb },
  642. { "INT3435", (kernel_ulong_t)&dw8250_dw_apb },
  643. { "INTC10EE", (kernel_ulong_t)&dw8250_dw_apb },
  644. { },
  645. };
  646. MODULE_DEVICE_TABLE(acpi, dw8250_acpi_match);
  647. static struct platform_driver dw8250_platform_driver = {
  648. .driver = {
  649. .name = "dw-apb-uart",
  650. .pm = pm_ptr(&dw8250_pm_ops),
  651. .of_match_table = dw8250_of_match,
  652. .acpi_match_table = dw8250_acpi_match,
  653. },
  654. .probe = dw8250_probe,
  655. .remove = dw8250_remove,
  656. };
  657. module_platform_driver(dw8250_platform_driver);
  658. MODULE_AUTHOR("Jamie Iles");
  659. MODULE_LICENSE("GPL");
  660. MODULE_DESCRIPTION("Synopsys DesignWare 8250 serial port driver");
  661. MODULE_ALIAS("platform:dw-apb-uart");