flexcan.c 35 KB

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  1. /*
  2. * flexcan.c - FLEXCAN CAN controller driver
  3. *
  4. * Copyright (c) 2005-2006 Varma Electronics Oy
  5. * Copyright (c) 2009 Sascha Hauer, Pengutronix
  6. * Copyright (c) 2010 Marc Kleine-Budde, Pengutronix
  7. *
  8. * Based on code originally by Andrey Volkov <avolkov@varma-el.com>
  9. *
  10. * LICENCE:
  11. * This program is free software; you can redistribute it and/or
  12. * modify it under the terms of the GNU General Public License as
  13. * published by the Free Software Foundation version 2.
  14. *
  15. * This program is distributed in the hope that it will be useful,
  16. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  18. * GNU General Public License for more details.
  19. *
  20. */
  21. #include <linux/netdevice.h>
  22. #include <linux/can.h>
  23. #include <linux/can/dev.h>
  24. #include <linux/can/error.h>
  25. #include <linux/can/led.h>
  26. #include <linux/clk.h>
  27. #include <linux/delay.h>
  28. #include <linux/if_arp.h>
  29. #include <linux/if_ether.h>
  30. #include <linux/interrupt.h>
  31. #include <linux/io.h>
  32. #include <linux/kernel.h>
  33. #include <linux/list.h>
  34. #include <linux/module.h>
  35. #include <linux/of.h>
  36. #include <linux/of_device.h>
  37. #include <linux/platform_device.h>
  38. #include <linux/regulator/consumer.h>
  39. #define DRV_NAME "flexcan"
  40. /* 8 for RX fifo and 2 error handling */
  41. #define FLEXCAN_NAPI_WEIGHT (8 + 2)
  42. /* FLEXCAN module configuration register (CANMCR) bits */
  43. #define FLEXCAN_MCR_MDIS BIT(31)
  44. #define FLEXCAN_MCR_FRZ BIT(30)
  45. #define FLEXCAN_MCR_FEN BIT(29)
  46. #define FLEXCAN_MCR_HALT BIT(28)
  47. #define FLEXCAN_MCR_NOT_RDY BIT(27)
  48. #define FLEXCAN_MCR_WAK_MSK BIT(26)
  49. #define FLEXCAN_MCR_SOFTRST BIT(25)
  50. #define FLEXCAN_MCR_FRZ_ACK BIT(24)
  51. #define FLEXCAN_MCR_SUPV BIT(23)
  52. #define FLEXCAN_MCR_SLF_WAK BIT(22)
  53. #define FLEXCAN_MCR_WRN_EN BIT(21)
  54. #define FLEXCAN_MCR_LPM_ACK BIT(20)
  55. #define FLEXCAN_MCR_WAK_SRC BIT(19)
  56. #define FLEXCAN_MCR_DOZE BIT(18)
  57. #define FLEXCAN_MCR_SRX_DIS BIT(17)
  58. #define FLEXCAN_MCR_BCC BIT(16)
  59. #define FLEXCAN_MCR_LPRIO_EN BIT(13)
  60. #define FLEXCAN_MCR_AEN BIT(12)
  61. #define FLEXCAN_MCR_MAXMB(x) ((x) & 0x7f)
  62. #define FLEXCAN_MCR_IDAM_A (0 << 8)
  63. #define FLEXCAN_MCR_IDAM_B (1 << 8)
  64. #define FLEXCAN_MCR_IDAM_C (2 << 8)
  65. #define FLEXCAN_MCR_IDAM_D (3 << 8)
  66. /* FLEXCAN control register (CANCTRL) bits */
  67. #define FLEXCAN_CTRL_PRESDIV(x) (((x) & 0xff) << 24)
  68. #define FLEXCAN_CTRL_RJW(x) (((x) & 0x03) << 22)
  69. #define FLEXCAN_CTRL_PSEG1(x) (((x) & 0x07) << 19)
  70. #define FLEXCAN_CTRL_PSEG2(x) (((x) & 0x07) << 16)
  71. #define FLEXCAN_CTRL_BOFF_MSK BIT(15)
  72. #define FLEXCAN_CTRL_ERR_MSK BIT(14)
  73. #define FLEXCAN_CTRL_CLK_SRC BIT(13)
  74. #define FLEXCAN_CTRL_LPB BIT(12)
  75. #define FLEXCAN_CTRL_TWRN_MSK BIT(11)
  76. #define FLEXCAN_CTRL_RWRN_MSK BIT(10)
  77. #define FLEXCAN_CTRL_SMP BIT(7)
  78. #define FLEXCAN_CTRL_BOFF_REC BIT(6)
  79. #define FLEXCAN_CTRL_TSYN BIT(5)
  80. #define FLEXCAN_CTRL_LBUF BIT(4)
  81. #define FLEXCAN_CTRL_LOM BIT(3)
  82. #define FLEXCAN_CTRL_PROPSEG(x) ((x) & 0x07)
  83. #define FLEXCAN_CTRL_ERR_BUS (FLEXCAN_CTRL_ERR_MSK)
  84. #define FLEXCAN_CTRL_ERR_STATE \
  85. (FLEXCAN_CTRL_TWRN_MSK | FLEXCAN_CTRL_RWRN_MSK | \
  86. FLEXCAN_CTRL_BOFF_MSK)
  87. #define FLEXCAN_CTRL_ERR_ALL \
  88. (FLEXCAN_CTRL_ERR_BUS | FLEXCAN_CTRL_ERR_STATE)
  89. /* FLEXCAN control register 2 (CTRL2) bits */
  90. #define FLEXCAN_CRL2_ECRWRE BIT(29)
  91. #define FLEXCAN_CRL2_WRMFRZ BIT(28)
  92. #define FLEXCAN_CRL2_RFFN(x) (((x) & 0x0f) << 24)
  93. #define FLEXCAN_CRL2_TASD(x) (((x) & 0x1f) << 19)
  94. #define FLEXCAN_CRL2_MRP BIT(18)
  95. #define FLEXCAN_CRL2_RRS BIT(17)
  96. #define FLEXCAN_CRL2_EACEN BIT(16)
  97. /* FLEXCAN memory error control register (MECR) bits */
  98. #define FLEXCAN_MECR_ECRWRDIS BIT(31)
  99. #define FLEXCAN_MECR_HANCEI_MSK BIT(19)
  100. #define FLEXCAN_MECR_FANCEI_MSK BIT(18)
  101. #define FLEXCAN_MECR_CEI_MSK BIT(16)
  102. #define FLEXCAN_MECR_HAERRIE BIT(15)
  103. #define FLEXCAN_MECR_FAERRIE BIT(14)
  104. #define FLEXCAN_MECR_EXTERRIE BIT(13)
  105. #define FLEXCAN_MECR_RERRDIS BIT(9)
  106. #define FLEXCAN_MECR_ECCDIS BIT(8)
  107. #define FLEXCAN_MECR_NCEFAFRZ BIT(7)
  108. /* FLEXCAN error and status register (ESR) bits */
  109. #define FLEXCAN_ESR_TWRN_INT BIT(17)
  110. #define FLEXCAN_ESR_RWRN_INT BIT(16)
  111. #define FLEXCAN_ESR_BIT1_ERR BIT(15)
  112. #define FLEXCAN_ESR_BIT0_ERR BIT(14)
  113. #define FLEXCAN_ESR_ACK_ERR BIT(13)
  114. #define FLEXCAN_ESR_CRC_ERR BIT(12)
  115. #define FLEXCAN_ESR_FRM_ERR BIT(11)
  116. #define FLEXCAN_ESR_STF_ERR BIT(10)
  117. #define FLEXCAN_ESR_TX_WRN BIT(9)
  118. #define FLEXCAN_ESR_RX_WRN BIT(8)
  119. #define FLEXCAN_ESR_IDLE BIT(7)
  120. #define FLEXCAN_ESR_TXRX BIT(6)
  121. #define FLEXCAN_EST_FLT_CONF_SHIFT (4)
  122. #define FLEXCAN_ESR_FLT_CONF_MASK (0x3 << FLEXCAN_EST_FLT_CONF_SHIFT)
  123. #define FLEXCAN_ESR_FLT_CONF_ACTIVE (0x0 << FLEXCAN_EST_FLT_CONF_SHIFT)
  124. #define FLEXCAN_ESR_FLT_CONF_PASSIVE (0x1 << FLEXCAN_EST_FLT_CONF_SHIFT)
  125. #define FLEXCAN_ESR_BOFF_INT BIT(2)
  126. #define FLEXCAN_ESR_ERR_INT BIT(1)
  127. #define FLEXCAN_ESR_WAK_INT BIT(0)
  128. #define FLEXCAN_ESR_ERR_BUS \
  129. (FLEXCAN_ESR_BIT1_ERR | FLEXCAN_ESR_BIT0_ERR | \
  130. FLEXCAN_ESR_ACK_ERR | FLEXCAN_ESR_CRC_ERR | \
  131. FLEXCAN_ESR_FRM_ERR | FLEXCAN_ESR_STF_ERR)
  132. #define FLEXCAN_ESR_ERR_STATE \
  133. (FLEXCAN_ESR_TWRN_INT | FLEXCAN_ESR_RWRN_INT | FLEXCAN_ESR_BOFF_INT)
  134. #define FLEXCAN_ESR_ERR_ALL \
  135. (FLEXCAN_ESR_ERR_BUS | FLEXCAN_ESR_ERR_STATE)
  136. #define FLEXCAN_ESR_ALL_INT \
  137. (FLEXCAN_ESR_TWRN_INT | FLEXCAN_ESR_RWRN_INT | \
  138. FLEXCAN_ESR_BOFF_INT | FLEXCAN_ESR_ERR_INT)
  139. /* FLEXCAN interrupt flag register (IFLAG) bits */
  140. /* Errata ERR005829 step7: Reserve first valid MB */
  141. #define FLEXCAN_TX_BUF_RESERVED 8
  142. #define FLEXCAN_TX_BUF_ID 9
  143. #define FLEXCAN_IFLAG_BUF(x) BIT(x)
  144. #define FLEXCAN_IFLAG_RX_FIFO_OVERFLOW BIT(7)
  145. #define FLEXCAN_IFLAG_RX_FIFO_WARN BIT(6)
  146. #define FLEXCAN_IFLAG_RX_FIFO_AVAILABLE BIT(5)
  147. #define FLEXCAN_IFLAG_DEFAULT \
  148. (FLEXCAN_IFLAG_RX_FIFO_OVERFLOW | FLEXCAN_IFLAG_RX_FIFO_AVAILABLE | \
  149. FLEXCAN_IFLAG_BUF(FLEXCAN_TX_BUF_ID))
  150. /* FLEXCAN message buffers */
  151. #define FLEXCAN_MB_CNT_CODE(x) (((x) & 0xf) << 24)
  152. #define FLEXCAN_MB_CODE_RX_INACTIVE (0x0 << 24)
  153. #define FLEXCAN_MB_CODE_RX_EMPTY (0x4 << 24)
  154. #define FLEXCAN_MB_CODE_RX_FULL (0x2 << 24)
  155. #define FLEXCAN_MB_CODE_RX_OVERRRUN (0x6 << 24)
  156. #define FLEXCAN_MB_CODE_RX_RANSWER (0xa << 24)
  157. #define FLEXCAN_MB_CODE_TX_INACTIVE (0x8 << 24)
  158. #define FLEXCAN_MB_CODE_TX_ABORT (0x9 << 24)
  159. #define FLEXCAN_MB_CODE_TX_DATA (0xc << 24)
  160. #define FLEXCAN_MB_CODE_TX_TANSWER (0xe << 24)
  161. #define FLEXCAN_MB_CNT_SRR BIT(22)
  162. #define FLEXCAN_MB_CNT_IDE BIT(21)
  163. #define FLEXCAN_MB_CNT_RTR BIT(20)
  164. #define FLEXCAN_MB_CNT_LENGTH(x) (((x) & 0xf) << 16)
  165. #define FLEXCAN_MB_CNT_TIMESTAMP(x) ((x) & 0xffff)
  166. #define FLEXCAN_MB_CODE_MASK (0xf0ffffff)
  167. #define FLEXCAN_TIMEOUT_US (50)
  168. /*
  169. * FLEXCAN hardware feature flags
  170. *
  171. * Below is some version info we got:
  172. * SOC Version IP-Version Glitch- [TR]WRN_INT Memory err
  173. * Filter? connected? detection
  174. * MX25 FlexCAN2 03.00.00.00 no no no
  175. * MX28 FlexCAN2 03.00.04.00 yes yes no
  176. * MX35 FlexCAN2 03.00.00.00 no no no
  177. * MX53 FlexCAN2 03.00.00.00 yes no no
  178. * MX6s FlexCAN3 10.00.12.00 yes yes no
  179. * VF610 FlexCAN3 ? no yes yes
  180. *
  181. * Some SOCs do not have the RX_WARN & TX_WARN interrupt line connected.
  182. */
  183. #define FLEXCAN_HAS_V10_FEATURES BIT(1) /* For core version >= 10 */
  184. #define FLEXCAN_HAS_BROKEN_ERR_STATE BIT(2) /* [TR]WRN_INT not connected */
  185. #define FLEXCAN_HAS_MECR_FEATURES BIT(3) /* Memory error detection */
  186. /* Structure of the message buffer */
  187. struct flexcan_mb {
  188. u32 can_ctrl;
  189. u32 can_id;
  190. u32 data[2];
  191. };
  192. /* Structure of the hardware registers */
  193. struct flexcan_regs {
  194. u32 mcr; /* 0x00 */
  195. u32 ctrl; /* 0x04 */
  196. u32 timer; /* 0x08 */
  197. u32 _reserved1; /* 0x0c */
  198. u32 rxgmask; /* 0x10 */
  199. u32 rx14mask; /* 0x14 */
  200. u32 rx15mask; /* 0x18 */
  201. u32 ecr; /* 0x1c */
  202. u32 esr; /* 0x20 */
  203. u32 imask2; /* 0x24 */
  204. u32 imask1; /* 0x28 */
  205. u32 iflag2; /* 0x2c */
  206. u32 iflag1; /* 0x30 */
  207. u32 crl2; /* 0x34 */
  208. u32 esr2; /* 0x38 */
  209. u32 imeur; /* 0x3c */
  210. u32 lrfr; /* 0x40 */
  211. u32 crcr; /* 0x44 */
  212. u32 rxfgmask; /* 0x48 */
  213. u32 rxfir; /* 0x4c */
  214. u32 _reserved3[12]; /* 0x50 */
  215. struct flexcan_mb cantxfg[64]; /* 0x80 */
  216. u32 _reserved4[408];
  217. u32 mecr; /* 0xae0 */
  218. u32 erriar; /* 0xae4 */
  219. u32 erridpr; /* 0xae8 */
  220. u32 errippr; /* 0xaec */
  221. u32 rerrar; /* 0xaf0 */
  222. u32 rerrdr; /* 0xaf4 */
  223. u32 rerrsynr; /* 0xaf8 */
  224. u32 errsr; /* 0xafc */
  225. };
  226. struct flexcan_devtype_data {
  227. u32 features; /* hardware controller features */
  228. };
  229. struct flexcan_priv {
  230. struct can_priv can;
  231. struct napi_struct napi;
  232. void __iomem *base;
  233. u32 reg_esr;
  234. u32 reg_ctrl_default;
  235. struct clk *clk_ipg;
  236. struct clk *clk_per;
  237. struct flexcan_platform_data *pdata;
  238. const struct flexcan_devtype_data *devtype_data;
  239. struct regulator *reg_xceiver;
  240. };
  241. static struct flexcan_devtype_data fsl_p1010_devtype_data = {
  242. .features = FLEXCAN_HAS_BROKEN_ERR_STATE,
  243. };
  244. static struct flexcan_devtype_data fsl_imx28_devtype_data;
  245. static struct flexcan_devtype_data fsl_imx6q_devtype_data = {
  246. .features = FLEXCAN_HAS_V10_FEATURES,
  247. };
  248. static struct flexcan_devtype_data fsl_vf610_devtype_data = {
  249. .features = FLEXCAN_HAS_V10_FEATURES | FLEXCAN_HAS_MECR_FEATURES,
  250. };
  251. static const struct can_bittiming_const flexcan_bittiming_const = {
  252. .name = DRV_NAME,
  253. .tseg1_min = 4,
  254. .tseg1_max = 16,
  255. .tseg2_min = 2,
  256. .tseg2_max = 8,
  257. .sjw_max = 4,
  258. .brp_min = 1,
  259. .brp_max = 256,
  260. .brp_inc = 1,
  261. };
  262. /*
  263. * Abstract off the read/write for arm versus ppc. This
  264. * assumes that PPC uses big-endian registers and everything
  265. * else uses little-endian registers, independent of CPU
  266. * endianess.
  267. */
  268. #if defined(CONFIG_PPC)
  269. static inline u32 flexcan_read(void __iomem *addr)
  270. {
  271. return in_be32(addr);
  272. }
  273. static inline void flexcan_write(u32 val, void __iomem *addr)
  274. {
  275. out_be32(addr, val);
  276. }
  277. #else
  278. static inline u32 flexcan_read(void __iomem *addr)
  279. {
  280. return readl(addr);
  281. }
  282. static inline void flexcan_write(u32 val, void __iomem *addr)
  283. {
  284. writel(val, addr);
  285. }
  286. #endif
  287. static inline int flexcan_transceiver_enable(const struct flexcan_priv *priv)
  288. {
  289. if (!priv->reg_xceiver)
  290. return 0;
  291. return regulator_enable(priv->reg_xceiver);
  292. }
  293. static inline int flexcan_transceiver_disable(const struct flexcan_priv *priv)
  294. {
  295. if (!priv->reg_xceiver)
  296. return 0;
  297. return regulator_disable(priv->reg_xceiver);
  298. }
  299. static inline int flexcan_has_and_handle_berr(const struct flexcan_priv *priv,
  300. u32 reg_esr)
  301. {
  302. return (priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) &&
  303. (reg_esr & FLEXCAN_ESR_ERR_BUS);
  304. }
  305. static int flexcan_chip_enable(struct flexcan_priv *priv)
  306. {
  307. struct flexcan_regs __iomem *regs = priv->base;
  308. unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
  309. u32 reg;
  310. reg = flexcan_read(&regs->mcr);
  311. reg &= ~FLEXCAN_MCR_MDIS;
  312. flexcan_write(reg, &regs->mcr);
  313. while (timeout-- && (flexcan_read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
  314. udelay(10);
  315. if (flexcan_read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK)
  316. return -ETIMEDOUT;
  317. return 0;
  318. }
  319. static int flexcan_chip_disable(struct flexcan_priv *priv)
  320. {
  321. struct flexcan_regs __iomem *regs = priv->base;
  322. unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
  323. u32 reg;
  324. reg = flexcan_read(&regs->mcr);
  325. reg |= FLEXCAN_MCR_MDIS;
  326. flexcan_write(reg, &regs->mcr);
  327. while (timeout-- && !(flexcan_read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
  328. udelay(10);
  329. if (!(flexcan_read(&regs->mcr) & FLEXCAN_MCR_LPM_ACK))
  330. return -ETIMEDOUT;
  331. return 0;
  332. }
  333. static int flexcan_chip_freeze(struct flexcan_priv *priv)
  334. {
  335. struct flexcan_regs __iomem *regs = priv->base;
  336. unsigned int timeout = 1000 * 1000 * 10 / priv->can.bittiming.bitrate;
  337. u32 reg;
  338. reg = flexcan_read(&regs->mcr);
  339. reg |= FLEXCAN_MCR_HALT;
  340. flexcan_write(reg, &regs->mcr);
  341. while (timeout-- && !(flexcan_read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
  342. udelay(100);
  343. if (!(flexcan_read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
  344. return -ETIMEDOUT;
  345. return 0;
  346. }
  347. static int flexcan_chip_unfreeze(struct flexcan_priv *priv)
  348. {
  349. struct flexcan_regs __iomem *regs = priv->base;
  350. unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
  351. u32 reg;
  352. reg = flexcan_read(&regs->mcr);
  353. reg &= ~FLEXCAN_MCR_HALT;
  354. flexcan_write(reg, &regs->mcr);
  355. while (timeout-- && (flexcan_read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK))
  356. udelay(10);
  357. if (flexcan_read(&regs->mcr) & FLEXCAN_MCR_FRZ_ACK)
  358. return -ETIMEDOUT;
  359. return 0;
  360. }
  361. static int flexcan_chip_softreset(struct flexcan_priv *priv)
  362. {
  363. struct flexcan_regs __iomem *regs = priv->base;
  364. unsigned int timeout = FLEXCAN_TIMEOUT_US / 10;
  365. flexcan_write(FLEXCAN_MCR_SOFTRST, &regs->mcr);
  366. while (timeout-- && (flexcan_read(&regs->mcr) & FLEXCAN_MCR_SOFTRST))
  367. udelay(10);
  368. if (flexcan_read(&regs->mcr) & FLEXCAN_MCR_SOFTRST)
  369. return -ETIMEDOUT;
  370. return 0;
  371. }
  372. static int __flexcan_get_berr_counter(const struct net_device *dev,
  373. struct can_berr_counter *bec)
  374. {
  375. const struct flexcan_priv *priv = netdev_priv(dev);
  376. struct flexcan_regs __iomem *regs = priv->base;
  377. u32 reg = flexcan_read(&regs->ecr);
  378. bec->txerr = (reg >> 0) & 0xff;
  379. bec->rxerr = (reg >> 8) & 0xff;
  380. return 0;
  381. }
  382. static int flexcan_get_berr_counter(const struct net_device *dev,
  383. struct can_berr_counter *bec)
  384. {
  385. const struct flexcan_priv *priv = netdev_priv(dev);
  386. int err;
  387. err = clk_prepare_enable(priv->clk_ipg);
  388. if (err)
  389. return err;
  390. err = clk_prepare_enable(priv->clk_per);
  391. if (err)
  392. goto out_disable_ipg;
  393. err = __flexcan_get_berr_counter(dev, bec);
  394. clk_disable_unprepare(priv->clk_per);
  395. out_disable_ipg:
  396. clk_disable_unprepare(priv->clk_ipg);
  397. return err;
  398. }
  399. static int flexcan_start_xmit(struct sk_buff *skb, struct net_device *dev)
  400. {
  401. const struct flexcan_priv *priv = netdev_priv(dev);
  402. struct flexcan_regs __iomem *regs = priv->base;
  403. struct can_frame *cf = (struct can_frame *)skb->data;
  404. u32 can_id;
  405. u32 ctrl = FLEXCAN_MB_CNT_CODE(0xc) | (cf->can_dlc << 16);
  406. if (can_dropped_invalid_skb(dev, skb))
  407. return NETDEV_TX_OK;
  408. netif_stop_queue(dev);
  409. if (cf->can_id & CAN_EFF_FLAG) {
  410. can_id = cf->can_id & CAN_EFF_MASK;
  411. ctrl |= FLEXCAN_MB_CNT_IDE | FLEXCAN_MB_CNT_SRR;
  412. } else {
  413. can_id = (cf->can_id & CAN_SFF_MASK) << 18;
  414. }
  415. if (cf->can_id & CAN_RTR_FLAG)
  416. ctrl |= FLEXCAN_MB_CNT_RTR;
  417. if (cf->can_dlc > 0) {
  418. u32 data = be32_to_cpup((__be32 *)&cf->data[0]);
  419. flexcan_write(data, &regs->cantxfg[FLEXCAN_TX_BUF_ID].data[0]);
  420. }
  421. if (cf->can_dlc > 3) {
  422. u32 data = be32_to_cpup((__be32 *)&cf->data[4]);
  423. flexcan_write(data, &regs->cantxfg[FLEXCAN_TX_BUF_ID].data[1]);
  424. }
  425. can_put_echo_skb(skb, dev, 0);
  426. flexcan_write(can_id, &regs->cantxfg[FLEXCAN_TX_BUF_ID].can_id);
  427. flexcan_write(ctrl, &regs->cantxfg[FLEXCAN_TX_BUF_ID].can_ctrl);
  428. /* Errata ERR005829 step8:
  429. * Write twice INACTIVE(0x8) code to first MB.
  430. */
  431. flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
  432. &regs->cantxfg[FLEXCAN_TX_BUF_RESERVED].can_ctrl);
  433. flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
  434. &regs->cantxfg[FLEXCAN_TX_BUF_RESERVED].can_ctrl);
  435. return NETDEV_TX_OK;
  436. }
  437. static void do_bus_err(struct net_device *dev,
  438. struct can_frame *cf, u32 reg_esr)
  439. {
  440. struct flexcan_priv *priv = netdev_priv(dev);
  441. int rx_errors = 0, tx_errors = 0;
  442. cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
  443. if (reg_esr & FLEXCAN_ESR_BIT1_ERR) {
  444. netdev_dbg(dev, "BIT1_ERR irq\n");
  445. cf->data[2] |= CAN_ERR_PROT_BIT1;
  446. tx_errors = 1;
  447. }
  448. if (reg_esr & FLEXCAN_ESR_BIT0_ERR) {
  449. netdev_dbg(dev, "BIT0_ERR irq\n");
  450. cf->data[2] |= CAN_ERR_PROT_BIT0;
  451. tx_errors = 1;
  452. }
  453. if (reg_esr & FLEXCAN_ESR_ACK_ERR) {
  454. netdev_dbg(dev, "ACK_ERR irq\n");
  455. cf->can_id |= CAN_ERR_ACK;
  456. cf->data[3] |= CAN_ERR_PROT_LOC_ACK;
  457. tx_errors = 1;
  458. }
  459. if (reg_esr & FLEXCAN_ESR_CRC_ERR) {
  460. netdev_dbg(dev, "CRC_ERR irq\n");
  461. cf->data[2] |= CAN_ERR_PROT_BIT;
  462. cf->data[3] |= CAN_ERR_PROT_LOC_CRC_SEQ;
  463. rx_errors = 1;
  464. }
  465. if (reg_esr & FLEXCAN_ESR_FRM_ERR) {
  466. netdev_dbg(dev, "FRM_ERR irq\n");
  467. cf->data[2] |= CAN_ERR_PROT_FORM;
  468. rx_errors = 1;
  469. }
  470. if (reg_esr & FLEXCAN_ESR_STF_ERR) {
  471. netdev_dbg(dev, "STF_ERR irq\n");
  472. cf->data[2] |= CAN_ERR_PROT_STUFF;
  473. rx_errors = 1;
  474. }
  475. priv->can.can_stats.bus_error++;
  476. if (rx_errors)
  477. dev->stats.rx_errors++;
  478. if (tx_errors)
  479. dev->stats.tx_errors++;
  480. }
  481. static int flexcan_poll_bus_err(struct net_device *dev, u32 reg_esr)
  482. {
  483. struct sk_buff *skb;
  484. struct can_frame *cf;
  485. skb = alloc_can_err_skb(dev, &cf);
  486. if (unlikely(!skb))
  487. return 0;
  488. do_bus_err(dev, cf, reg_esr);
  489. netif_receive_skb(skb);
  490. dev->stats.rx_packets++;
  491. dev->stats.rx_bytes += cf->can_dlc;
  492. return 1;
  493. }
  494. static int flexcan_poll_state(struct net_device *dev, u32 reg_esr)
  495. {
  496. struct flexcan_priv *priv = netdev_priv(dev);
  497. struct sk_buff *skb;
  498. struct can_frame *cf;
  499. enum can_state new_state = 0, rx_state = 0, tx_state = 0;
  500. int flt;
  501. struct can_berr_counter bec;
  502. flt = reg_esr & FLEXCAN_ESR_FLT_CONF_MASK;
  503. if (likely(flt == FLEXCAN_ESR_FLT_CONF_ACTIVE)) {
  504. tx_state = unlikely(reg_esr & FLEXCAN_ESR_TX_WRN) ?
  505. CAN_STATE_ERROR_WARNING : CAN_STATE_ERROR_ACTIVE;
  506. rx_state = unlikely(reg_esr & FLEXCAN_ESR_RX_WRN) ?
  507. CAN_STATE_ERROR_WARNING : CAN_STATE_ERROR_ACTIVE;
  508. new_state = max(tx_state, rx_state);
  509. } else if (unlikely(flt == FLEXCAN_ESR_FLT_CONF_PASSIVE)) {
  510. __flexcan_get_berr_counter(dev, &bec);
  511. new_state = CAN_STATE_ERROR_PASSIVE;
  512. rx_state = bec.rxerr >= bec.txerr ? new_state : 0;
  513. tx_state = bec.rxerr <= bec.txerr ? new_state : 0;
  514. } else {
  515. new_state = CAN_STATE_BUS_OFF;
  516. }
  517. /* state hasn't changed */
  518. if (likely(new_state == priv->can.state))
  519. return 0;
  520. skb = alloc_can_err_skb(dev, &cf);
  521. if (unlikely(!skb))
  522. return 0;
  523. can_change_state(dev, cf, tx_state, rx_state);
  524. if (unlikely(new_state == CAN_STATE_BUS_OFF))
  525. can_bus_off(dev);
  526. netif_receive_skb(skb);
  527. dev->stats.rx_packets++;
  528. dev->stats.rx_bytes += cf->can_dlc;
  529. return 1;
  530. }
  531. static void flexcan_read_fifo(const struct net_device *dev,
  532. struct can_frame *cf)
  533. {
  534. const struct flexcan_priv *priv = netdev_priv(dev);
  535. struct flexcan_regs __iomem *regs = priv->base;
  536. struct flexcan_mb __iomem *mb = &regs->cantxfg[0];
  537. u32 reg_ctrl, reg_id;
  538. reg_ctrl = flexcan_read(&mb->can_ctrl);
  539. reg_id = flexcan_read(&mb->can_id);
  540. if (reg_ctrl & FLEXCAN_MB_CNT_IDE)
  541. cf->can_id = ((reg_id >> 0) & CAN_EFF_MASK) | CAN_EFF_FLAG;
  542. else
  543. cf->can_id = (reg_id >> 18) & CAN_SFF_MASK;
  544. if (reg_ctrl & FLEXCAN_MB_CNT_RTR)
  545. cf->can_id |= CAN_RTR_FLAG;
  546. cf->can_dlc = get_can_dlc((reg_ctrl >> 16) & 0xf);
  547. *(__be32 *)(cf->data + 0) = cpu_to_be32(flexcan_read(&mb->data[0]));
  548. *(__be32 *)(cf->data + 4) = cpu_to_be32(flexcan_read(&mb->data[1]));
  549. /* mark as read */
  550. flexcan_write(FLEXCAN_IFLAG_RX_FIFO_AVAILABLE, &regs->iflag1);
  551. flexcan_read(&regs->timer);
  552. }
  553. static int flexcan_read_frame(struct net_device *dev)
  554. {
  555. struct net_device_stats *stats = &dev->stats;
  556. struct can_frame *cf;
  557. struct sk_buff *skb;
  558. skb = alloc_can_skb(dev, &cf);
  559. if (unlikely(!skb)) {
  560. stats->rx_dropped++;
  561. return 0;
  562. }
  563. flexcan_read_fifo(dev, cf);
  564. netif_receive_skb(skb);
  565. stats->rx_packets++;
  566. stats->rx_bytes += cf->can_dlc;
  567. can_led_event(dev, CAN_LED_EVENT_RX);
  568. return 1;
  569. }
  570. static int flexcan_poll(struct napi_struct *napi, int quota)
  571. {
  572. struct net_device *dev = napi->dev;
  573. const struct flexcan_priv *priv = netdev_priv(dev);
  574. struct flexcan_regs __iomem *regs = priv->base;
  575. u32 reg_iflag1, reg_esr;
  576. int work_done = 0;
  577. /*
  578. * The error bits are cleared on read,
  579. * use saved value from irq handler.
  580. */
  581. reg_esr = flexcan_read(&regs->esr) | priv->reg_esr;
  582. /* handle state changes */
  583. work_done += flexcan_poll_state(dev, reg_esr);
  584. /* handle RX-FIFO */
  585. reg_iflag1 = flexcan_read(&regs->iflag1);
  586. while (reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_AVAILABLE &&
  587. work_done < quota) {
  588. work_done += flexcan_read_frame(dev);
  589. reg_iflag1 = flexcan_read(&regs->iflag1);
  590. }
  591. /* report bus errors */
  592. if (flexcan_has_and_handle_berr(priv, reg_esr) && work_done < quota)
  593. work_done += flexcan_poll_bus_err(dev, reg_esr);
  594. if (work_done < quota) {
  595. napi_complete(napi);
  596. /* enable IRQs */
  597. flexcan_write(FLEXCAN_IFLAG_DEFAULT, &regs->imask1);
  598. flexcan_write(priv->reg_ctrl_default, &regs->ctrl);
  599. }
  600. return work_done;
  601. }
  602. static irqreturn_t flexcan_irq(int irq, void *dev_id)
  603. {
  604. struct net_device *dev = dev_id;
  605. struct net_device_stats *stats = &dev->stats;
  606. struct flexcan_priv *priv = netdev_priv(dev);
  607. struct flexcan_regs __iomem *regs = priv->base;
  608. u32 reg_iflag1, reg_esr;
  609. reg_iflag1 = flexcan_read(&regs->iflag1);
  610. reg_esr = flexcan_read(&regs->esr);
  611. /* ACK all bus error and state change IRQ sources */
  612. if (reg_esr & FLEXCAN_ESR_ALL_INT)
  613. flexcan_write(reg_esr & FLEXCAN_ESR_ALL_INT, &regs->esr);
  614. /*
  615. * schedule NAPI in case of:
  616. * - rx IRQ
  617. * - state change IRQ
  618. * - bus error IRQ and bus error reporting is activated
  619. */
  620. if ((reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_AVAILABLE) ||
  621. (reg_esr & FLEXCAN_ESR_ERR_STATE) ||
  622. flexcan_has_and_handle_berr(priv, reg_esr)) {
  623. /*
  624. * The error bits are cleared on read,
  625. * save them for later use.
  626. */
  627. priv->reg_esr = reg_esr & FLEXCAN_ESR_ERR_BUS;
  628. flexcan_write(FLEXCAN_IFLAG_DEFAULT &
  629. ~FLEXCAN_IFLAG_RX_FIFO_AVAILABLE, &regs->imask1);
  630. flexcan_write(priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_ALL,
  631. &regs->ctrl);
  632. napi_schedule(&priv->napi);
  633. }
  634. /* FIFO overflow */
  635. if (reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_OVERFLOW) {
  636. flexcan_write(FLEXCAN_IFLAG_RX_FIFO_OVERFLOW, &regs->iflag1);
  637. dev->stats.rx_over_errors++;
  638. dev->stats.rx_errors++;
  639. }
  640. /* transmission complete interrupt */
  641. if (reg_iflag1 & (1 << FLEXCAN_TX_BUF_ID)) {
  642. stats->tx_bytes += can_get_echo_skb(dev, 0);
  643. stats->tx_packets++;
  644. can_led_event(dev, CAN_LED_EVENT_TX);
  645. /* after sending a RTR frame mailbox is in RX mode */
  646. flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
  647. &regs->cantxfg[FLEXCAN_TX_BUF_ID].can_ctrl);
  648. flexcan_write((1 << FLEXCAN_TX_BUF_ID), &regs->iflag1);
  649. netif_wake_queue(dev);
  650. }
  651. return IRQ_HANDLED;
  652. }
  653. static void flexcan_set_bittiming(struct net_device *dev)
  654. {
  655. const struct flexcan_priv *priv = netdev_priv(dev);
  656. const struct can_bittiming *bt = &priv->can.bittiming;
  657. struct flexcan_regs __iomem *regs = priv->base;
  658. u32 reg;
  659. reg = flexcan_read(&regs->ctrl);
  660. reg &= ~(FLEXCAN_CTRL_PRESDIV(0xff) |
  661. FLEXCAN_CTRL_RJW(0x3) |
  662. FLEXCAN_CTRL_PSEG1(0x7) |
  663. FLEXCAN_CTRL_PSEG2(0x7) |
  664. FLEXCAN_CTRL_PROPSEG(0x7) |
  665. FLEXCAN_CTRL_LPB |
  666. FLEXCAN_CTRL_SMP |
  667. FLEXCAN_CTRL_LOM);
  668. reg |= FLEXCAN_CTRL_PRESDIV(bt->brp - 1) |
  669. FLEXCAN_CTRL_PSEG1(bt->phase_seg1 - 1) |
  670. FLEXCAN_CTRL_PSEG2(bt->phase_seg2 - 1) |
  671. FLEXCAN_CTRL_RJW(bt->sjw - 1) |
  672. FLEXCAN_CTRL_PROPSEG(bt->prop_seg - 1);
  673. if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
  674. reg |= FLEXCAN_CTRL_LPB;
  675. if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
  676. reg |= FLEXCAN_CTRL_LOM;
  677. if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
  678. reg |= FLEXCAN_CTRL_SMP;
  679. netdev_info(dev, "writing ctrl=0x%08x\n", reg);
  680. flexcan_write(reg, &regs->ctrl);
  681. /* print chip status */
  682. netdev_dbg(dev, "%s: mcr=0x%08x ctrl=0x%08x\n", __func__,
  683. flexcan_read(&regs->mcr), flexcan_read(&regs->ctrl));
  684. }
  685. /*
  686. * flexcan_chip_start
  687. *
  688. * this functions is entered with clocks enabled
  689. *
  690. */
  691. static int flexcan_chip_start(struct net_device *dev)
  692. {
  693. struct flexcan_priv *priv = netdev_priv(dev);
  694. struct flexcan_regs __iomem *regs = priv->base;
  695. u32 reg_mcr, reg_ctrl, reg_crl2, reg_mecr;
  696. int err, i;
  697. /* enable module */
  698. err = flexcan_chip_enable(priv);
  699. if (err)
  700. return err;
  701. /* soft reset */
  702. err = flexcan_chip_softreset(priv);
  703. if (err)
  704. goto out_chip_disable;
  705. flexcan_set_bittiming(dev);
  706. /*
  707. * MCR
  708. *
  709. * enable freeze
  710. * enable fifo
  711. * halt now
  712. * only supervisor access
  713. * enable warning int
  714. * choose format C
  715. * disable local echo
  716. *
  717. */
  718. reg_mcr = flexcan_read(&regs->mcr);
  719. reg_mcr &= ~FLEXCAN_MCR_MAXMB(0xff);
  720. reg_mcr |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_FEN | FLEXCAN_MCR_HALT |
  721. FLEXCAN_MCR_SUPV | FLEXCAN_MCR_WRN_EN |
  722. FLEXCAN_MCR_IDAM_C | FLEXCAN_MCR_SRX_DIS |
  723. FLEXCAN_MCR_MAXMB(FLEXCAN_TX_BUF_ID);
  724. netdev_dbg(dev, "%s: writing mcr=0x%08x", __func__, reg_mcr);
  725. flexcan_write(reg_mcr, &regs->mcr);
  726. /*
  727. * CTRL
  728. *
  729. * disable timer sync feature
  730. *
  731. * disable auto busoff recovery
  732. * transmit lowest buffer first
  733. *
  734. * enable tx and rx warning interrupt
  735. * enable bus off interrupt
  736. * (== FLEXCAN_CTRL_ERR_STATE)
  737. */
  738. reg_ctrl = flexcan_read(&regs->ctrl);
  739. reg_ctrl &= ~FLEXCAN_CTRL_TSYN;
  740. reg_ctrl |= FLEXCAN_CTRL_BOFF_REC | FLEXCAN_CTRL_LBUF |
  741. FLEXCAN_CTRL_ERR_STATE;
  742. /*
  743. * enable the "error interrupt" (FLEXCAN_CTRL_ERR_MSK),
  744. * on most Flexcan cores, too. Otherwise we don't get
  745. * any error warning or passive interrupts.
  746. */
  747. if (priv->devtype_data->features & FLEXCAN_HAS_BROKEN_ERR_STATE ||
  748. priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
  749. reg_ctrl |= FLEXCAN_CTRL_ERR_MSK;
  750. else
  751. reg_ctrl &= ~FLEXCAN_CTRL_ERR_MSK;
  752. /* save for later use */
  753. priv->reg_ctrl_default = reg_ctrl;
  754. netdev_dbg(dev, "%s: writing ctrl=0x%08x", __func__, reg_ctrl);
  755. flexcan_write(reg_ctrl, &regs->ctrl);
  756. /* clear and invalidate all mailboxes first */
  757. for (i = FLEXCAN_TX_BUF_ID; i < ARRAY_SIZE(regs->cantxfg); i++) {
  758. flexcan_write(FLEXCAN_MB_CODE_RX_INACTIVE,
  759. &regs->cantxfg[i].can_ctrl);
  760. }
  761. /* Errata ERR005829: mark first TX mailbox as INACTIVE */
  762. flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
  763. &regs->cantxfg[FLEXCAN_TX_BUF_RESERVED].can_ctrl);
  764. /* mark TX mailbox as INACTIVE */
  765. flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
  766. &regs->cantxfg[FLEXCAN_TX_BUF_ID].can_ctrl);
  767. /* acceptance mask/acceptance code (accept everything) */
  768. flexcan_write(0x0, &regs->rxgmask);
  769. flexcan_write(0x0, &regs->rx14mask);
  770. flexcan_write(0x0, &regs->rx15mask);
  771. if (priv->devtype_data->features & FLEXCAN_HAS_V10_FEATURES)
  772. flexcan_write(0x0, &regs->rxfgmask);
  773. /*
  774. * On Vybrid, disable memory error detection interrupts
  775. * and freeze mode.
  776. * This also works around errata e5295 which generates
  777. * false positive memory errors and put the device in
  778. * freeze mode.
  779. */
  780. if (priv->devtype_data->features & FLEXCAN_HAS_MECR_FEATURES) {
  781. /*
  782. * Follow the protocol as described in "Detection
  783. * and Correction of Memory Errors" to write to
  784. * MECR register
  785. */
  786. reg_crl2 = flexcan_read(&regs->crl2);
  787. reg_crl2 |= FLEXCAN_CRL2_ECRWRE;
  788. flexcan_write(reg_crl2, &regs->crl2);
  789. reg_mecr = flexcan_read(&regs->mecr);
  790. reg_mecr &= ~FLEXCAN_MECR_ECRWRDIS;
  791. flexcan_write(reg_mecr, &regs->mecr);
  792. reg_mecr &= ~(FLEXCAN_MECR_NCEFAFRZ | FLEXCAN_MECR_HANCEI_MSK |
  793. FLEXCAN_MECR_FANCEI_MSK);
  794. flexcan_write(reg_mecr, &regs->mecr);
  795. }
  796. err = flexcan_transceiver_enable(priv);
  797. if (err)
  798. goto out_chip_disable;
  799. /* synchronize with the can bus */
  800. err = flexcan_chip_unfreeze(priv);
  801. if (err)
  802. goto out_transceiver_disable;
  803. priv->can.state = CAN_STATE_ERROR_ACTIVE;
  804. /* enable FIFO interrupts */
  805. flexcan_write(FLEXCAN_IFLAG_DEFAULT, &regs->imask1);
  806. /* print chip status */
  807. netdev_dbg(dev, "%s: reading mcr=0x%08x ctrl=0x%08x\n", __func__,
  808. flexcan_read(&regs->mcr), flexcan_read(&regs->ctrl));
  809. return 0;
  810. out_transceiver_disable:
  811. flexcan_transceiver_disable(priv);
  812. out_chip_disable:
  813. flexcan_chip_disable(priv);
  814. return err;
  815. }
  816. /*
  817. * flexcan_chip_stop
  818. *
  819. * this functions is entered with clocks enabled
  820. *
  821. */
  822. static void flexcan_chip_stop(struct net_device *dev)
  823. {
  824. struct flexcan_priv *priv = netdev_priv(dev);
  825. struct flexcan_regs __iomem *regs = priv->base;
  826. /* freeze + disable module */
  827. flexcan_chip_freeze(priv);
  828. flexcan_chip_disable(priv);
  829. /* Disable all interrupts */
  830. flexcan_write(0, &regs->imask1);
  831. flexcan_write(priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_ALL,
  832. &regs->ctrl);
  833. flexcan_transceiver_disable(priv);
  834. priv->can.state = CAN_STATE_STOPPED;
  835. return;
  836. }
  837. static int flexcan_open(struct net_device *dev)
  838. {
  839. struct flexcan_priv *priv = netdev_priv(dev);
  840. int err;
  841. err = clk_prepare_enable(priv->clk_ipg);
  842. if (err)
  843. return err;
  844. err = clk_prepare_enable(priv->clk_per);
  845. if (err)
  846. goto out_disable_ipg;
  847. err = open_candev(dev);
  848. if (err)
  849. goto out_disable_per;
  850. err = request_irq(dev->irq, flexcan_irq, IRQF_SHARED, dev->name, dev);
  851. if (err)
  852. goto out_close;
  853. /* start chip and queuing */
  854. err = flexcan_chip_start(dev);
  855. if (err)
  856. goto out_free_irq;
  857. can_led_event(dev, CAN_LED_EVENT_OPEN);
  858. napi_enable(&priv->napi);
  859. netif_start_queue(dev);
  860. return 0;
  861. out_free_irq:
  862. free_irq(dev->irq, dev);
  863. out_close:
  864. close_candev(dev);
  865. out_disable_per:
  866. clk_disable_unprepare(priv->clk_per);
  867. out_disable_ipg:
  868. clk_disable_unprepare(priv->clk_ipg);
  869. return err;
  870. }
  871. static int flexcan_close(struct net_device *dev)
  872. {
  873. struct flexcan_priv *priv = netdev_priv(dev);
  874. netif_stop_queue(dev);
  875. napi_disable(&priv->napi);
  876. flexcan_chip_stop(dev);
  877. free_irq(dev->irq, dev);
  878. clk_disable_unprepare(priv->clk_per);
  879. clk_disable_unprepare(priv->clk_ipg);
  880. close_candev(dev);
  881. can_led_event(dev, CAN_LED_EVENT_STOP);
  882. return 0;
  883. }
  884. static int flexcan_set_mode(struct net_device *dev, enum can_mode mode)
  885. {
  886. int err;
  887. switch (mode) {
  888. case CAN_MODE_START:
  889. err = flexcan_chip_start(dev);
  890. if (err)
  891. return err;
  892. netif_wake_queue(dev);
  893. break;
  894. default:
  895. return -EOPNOTSUPP;
  896. }
  897. return 0;
  898. }
  899. static const struct net_device_ops flexcan_netdev_ops = {
  900. .ndo_open = flexcan_open,
  901. .ndo_stop = flexcan_close,
  902. .ndo_start_xmit = flexcan_start_xmit,
  903. .ndo_change_mtu = can_change_mtu,
  904. };
  905. static int register_flexcandev(struct net_device *dev)
  906. {
  907. struct flexcan_priv *priv = netdev_priv(dev);
  908. struct flexcan_regs __iomem *regs = priv->base;
  909. u32 reg, err;
  910. err = clk_prepare_enable(priv->clk_ipg);
  911. if (err)
  912. return err;
  913. err = clk_prepare_enable(priv->clk_per);
  914. if (err)
  915. goto out_disable_ipg;
  916. /* select "bus clock", chip must be disabled */
  917. err = flexcan_chip_disable(priv);
  918. if (err)
  919. goto out_disable_per;
  920. reg = flexcan_read(&regs->ctrl);
  921. reg |= FLEXCAN_CTRL_CLK_SRC;
  922. flexcan_write(reg, &regs->ctrl);
  923. err = flexcan_chip_enable(priv);
  924. if (err)
  925. goto out_chip_disable;
  926. /* set freeze, halt and activate FIFO, restrict register access */
  927. reg = flexcan_read(&regs->mcr);
  928. reg |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_HALT |
  929. FLEXCAN_MCR_FEN | FLEXCAN_MCR_SUPV;
  930. flexcan_write(reg, &regs->mcr);
  931. /*
  932. * Currently we only support newer versions of this core
  933. * featuring a RX FIFO. Older cores found on some Coldfire
  934. * derivates are not yet supported.
  935. */
  936. reg = flexcan_read(&regs->mcr);
  937. if (!(reg & FLEXCAN_MCR_FEN)) {
  938. netdev_err(dev, "Could not enable RX FIFO, unsupported core\n");
  939. err = -ENODEV;
  940. goto out_chip_disable;
  941. }
  942. err = register_candev(dev);
  943. /* disable core and turn off clocks */
  944. out_chip_disable:
  945. flexcan_chip_disable(priv);
  946. out_disable_per:
  947. clk_disable_unprepare(priv->clk_per);
  948. out_disable_ipg:
  949. clk_disable_unprepare(priv->clk_ipg);
  950. return err;
  951. }
  952. static void unregister_flexcandev(struct net_device *dev)
  953. {
  954. unregister_candev(dev);
  955. }
  956. static const struct of_device_id flexcan_of_match[] = {
  957. { .compatible = "fsl,imx6q-flexcan", .data = &fsl_imx6q_devtype_data, },
  958. { .compatible = "fsl,imx28-flexcan", .data = &fsl_imx28_devtype_data, },
  959. { .compatible = "fsl,p1010-flexcan", .data = &fsl_p1010_devtype_data, },
  960. { .compatible = "fsl,vf610-flexcan", .data = &fsl_vf610_devtype_data, },
  961. { /* sentinel */ },
  962. };
  963. MODULE_DEVICE_TABLE(of, flexcan_of_match);
  964. static const struct platform_device_id flexcan_id_table[] = {
  965. { .name = "flexcan", .driver_data = (kernel_ulong_t)&fsl_p1010_devtype_data, },
  966. { /* sentinel */ },
  967. };
  968. MODULE_DEVICE_TABLE(platform, flexcan_id_table);
  969. static int flexcan_probe(struct platform_device *pdev)
  970. {
  971. const struct of_device_id *of_id;
  972. const struct flexcan_devtype_data *devtype_data;
  973. struct net_device *dev;
  974. struct flexcan_priv *priv;
  975. struct resource *mem;
  976. struct clk *clk_ipg = NULL, *clk_per = NULL;
  977. void __iomem *base;
  978. int err, irq;
  979. u32 clock_freq = 0;
  980. if (pdev->dev.of_node)
  981. of_property_read_u32(pdev->dev.of_node,
  982. "clock-frequency", &clock_freq);
  983. if (!clock_freq) {
  984. clk_ipg = devm_clk_get(&pdev->dev, "ipg");
  985. if (IS_ERR(clk_ipg)) {
  986. dev_err(&pdev->dev, "no ipg clock defined\n");
  987. return PTR_ERR(clk_ipg);
  988. }
  989. clk_per = devm_clk_get(&pdev->dev, "per");
  990. if (IS_ERR(clk_per)) {
  991. dev_err(&pdev->dev, "no per clock defined\n");
  992. return PTR_ERR(clk_per);
  993. }
  994. clock_freq = clk_get_rate(clk_per);
  995. }
  996. mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  997. irq = platform_get_irq(pdev, 0);
  998. if (irq <= 0)
  999. return -ENODEV;
  1000. base = devm_ioremap_resource(&pdev->dev, mem);
  1001. if (IS_ERR(base))
  1002. return PTR_ERR(base);
  1003. of_id = of_match_device(flexcan_of_match, &pdev->dev);
  1004. if (of_id) {
  1005. devtype_data = of_id->data;
  1006. } else if (platform_get_device_id(pdev)->driver_data) {
  1007. devtype_data = (struct flexcan_devtype_data *)
  1008. platform_get_device_id(pdev)->driver_data;
  1009. } else {
  1010. return -ENODEV;
  1011. }
  1012. dev = alloc_candev(sizeof(struct flexcan_priv), 1);
  1013. if (!dev)
  1014. return -ENOMEM;
  1015. dev->netdev_ops = &flexcan_netdev_ops;
  1016. dev->irq = irq;
  1017. dev->flags |= IFF_ECHO;
  1018. priv = netdev_priv(dev);
  1019. priv->can.clock.freq = clock_freq;
  1020. priv->can.bittiming_const = &flexcan_bittiming_const;
  1021. priv->can.do_set_mode = flexcan_set_mode;
  1022. priv->can.do_get_berr_counter = flexcan_get_berr_counter;
  1023. priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
  1024. CAN_CTRLMODE_LISTENONLY | CAN_CTRLMODE_3_SAMPLES |
  1025. CAN_CTRLMODE_BERR_REPORTING;
  1026. priv->base = base;
  1027. priv->clk_ipg = clk_ipg;
  1028. priv->clk_per = clk_per;
  1029. priv->pdata = dev_get_platdata(&pdev->dev);
  1030. priv->devtype_data = devtype_data;
  1031. priv->reg_xceiver = devm_regulator_get(&pdev->dev, "xceiver");
  1032. if (IS_ERR(priv->reg_xceiver))
  1033. priv->reg_xceiver = NULL;
  1034. netif_napi_add(dev, &priv->napi, flexcan_poll, FLEXCAN_NAPI_WEIGHT);
  1035. platform_set_drvdata(pdev, dev);
  1036. SET_NETDEV_DEV(dev, &pdev->dev);
  1037. err = register_flexcandev(dev);
  1038. if (err) {
  1039. dev_err(&pdev->dev, "registering netdev failed\n");
  1040. goto failed_register;
  1041. }
  1042. devm_can_led_init(dev);
  1043. dev_info(&pdev->dev, "device registered (reg_base=%p, irq=%d)\n",
  1044. priv->base, dev->irq);
  1045. return 0;
  1046. failed_register:
  1047. free_candev(dev);
  1048. return err;
  1049. }
  1050. static int flexcan_remove(struct platform_device *pdev)
  1051. {
  1052. struct net_device *dev = platform_get_drvdata(pdev);
  1053. struct flexcan_priv *priv = netdev_priv(dev);
  1054. unregister_flexcandev(dev);
  1055. netif_napi_del(&priv->napi);
  1056. free_candev(dev);
  1057. return 0;
  1058. }
  1059. static int __maybe_unused flexcan_suspend(struct device *device)
  1060. {
  1061. struct net_device *dev = dev_get_drvdata(device);
  1062. struct flexcan_priv *priv = netdev_priv(dev);
  1063. int err;
  1064. err = flexcan_chip_disable(priv);
  1065. if (err)
  1066. return err;
  1067. if (netif_running(dev)) {
  1068. netif_stop_queue(dev);
  1069. netif_device_detach(dev);
  1070. }
  1071. priv->can.state = CAN_STATE_SLEEPING;
  1072. return 0;
  1073. }
  1074. static int __maybe_unused flexcan_resume(struct device *device)
  1075. {
  1076. struct net_device *dev = dev_get_drvdata(device);
  1077. struct flexcan_priv *priv = netdev_priv(dev);
  1078. priv->can.state = CAN_STATE_ERROR_ACTIVE;
  1079. if (netif_running(dev)) {
  1080. netif_device_attach(dev);
  1081. netif_start_queue(dev);
  1082. }
  1083. return flexcan_chip_enable(priv);
  1084. }
  1085. static SIMPLE_DEV_PM_OPS(flexcan_pm_ops, flexcan_suspend, flexcan_resume);
  1086. static struct platform_driver flexcan_driver = {
  1087. .driver = {
  1088. .name = DRV_NAME,
  1089. .pm = &flexcan_pm_ops,
  1090. .of_match_table = flexcan_of_match,
  1091. },
  1092. .probe = flexcan_probe,
  1093. .remove = flexcan_remove,
  1094. .id_table = flexcan_id_table,
  1095. };
  1096. module_platform_driver(flexcan_driver);
  1097. MODULE_AUTHOR("Sascha Hauer <kernel@pengutronix.de>, "
  1098. "Marc Kleine-Budde <kernel@pengutronix.de>");
  1099. MODULE_LICENSE("GPL v2");
  1100. MODULE_DESCRIPTION("CAN port driver for flexcan based chip");