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 {
  510. __flexcan_get_berr_counter(dev, &bec);
  511. new_state = flt == FLEXCAN_ESR_FLT_CONF_PASSIVE ?
  512. CAN_STATE_ERROR_PASSIVE : CAN_STATE_BUS_OFF;
  513. rx_state = bec.rxerr >= bec.txerr ? new_state : 0;
  514. tx_state = bec.rxerr <= bec.txerr ? new_state : 0;
  515. }
  516. /* state hasn't changed */
  517. if (likely(new_state == priv->can.state))
  518. return 0;
  519. skb = alloc_can_err_skb(dev, &cf);
  520. if (unlikely(!skb))
  521. return 0;
  522. can_change_state(dev, cf, tx_state, rx_state);
  523. if (unlikely(new_state == CAN_STATE_BUS_OFF))
  524. can_bus_off(dev);
  525. netif_receive_skb(skb);
  526. dev->stats.rx_packets++;
  527. dev->stats.rx_bytes += cf->can_dlc;
  528. return 1;
  529. }
  530. static void flexcan_read_fifo(const struct net_device *dev,
  531. struct can_frame *cf)
  532. {
  533. const struct flexcan_priv *priv = netdev_priv(dev);
  534. struct flexcan_regs __iomem *regs = priv->base;
  535. struct flexcan_mb __iomem *mb = &regs->cantxfg[0];
  536. u32 reg_ctrl, reg_id;
  537. reg_ctrl = flexcan_read(&mb->can_ctrl);
  538. reg_id = flexcan_read(&mb->can_id);
  539. if (reg_ctrl & FLEXCAN_MB_CNT_IDE)
  540. cf->can_id = ((reg_id >> 0) & CAN_EFF_MASK) | CAN_EFF_FLAG;
  541. else
  542. cf->can_id = (reg_id >> 18) & CAN_SFF_MASK;
  543. if (reg_ctrl & FLEXCAN_MB_CNT_RTR)
  544. cf->can_id |= CAN_RTR_FLAG;
  545. cf->can_dlc = get_can_dlc((reg_ctrl >> 16) & 0xf);
  546. *(__be32 *)(cf->data + 0) = cpu_to_be32(flexcan_read(&mb->data[0]));
  547. *(__be32 *)(cf->data + 4) = cpu_to_be32(flexcan_read(&mb->data[1]));
  548. /* mark as read */
  549. flexcan_write(FLEXCAN_IFLAG_RX_FIFO_AVAILABLE, &regs->iflag1);
  550. flexcan_read(&regs->timer);
  551. }
  552. static int flexcan_read_frame(struct net_device *dev)
  553. {
  554. struct net_device_stats *stats = &dev->stats;
  555. struct can_frame *cf;
  556. struct sk_buff *skb;
  557. skb = alloc_can_skb(dev, &cf);
  558. if (unlikely(!skb)) {
  559. stats->rx_dropped++;
  560. return 0;
  561. }
  562. flexcan_read_fifo(dev, cf);
  563. netif_receive_skb(skb);
  564. stats->rx_packets++;
  565. stats->rx_bytes += cf->can_dlc;
  566. can_led_event(dev, CAN_LED_EVENT_RX);
  567. return 1;
  568. }
  569. static int flexcan_poll(struct napi_struct *napi, int quota)
  570. {
  571. struct net_device *dev = napi->dev;
  572. const struct flexcan_priv *priv = netdev_priv(dev);
  573. struct flexcan_regs __iomem *regs = priv->base;
  574. u32 reg_iflag1, reg_esr;
  575. int work_done = 0;
  576. /*
  577. * The error bits are cleared on read,
  578. * use saved value from irq handler.
  579. */
  580. reg_esr = flexcan_read(&regs->esr) | priv->reg_esr;
  581. /* handle state changes */
  582. work_done += flexcan_poll_state(dev, reg_esr);
  583. /* handle RX-FIFO */
  584. reg_iflag1 = flexcan_read(&regs->iflag1);
  585. while (reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_AVAILABLE &&
  586. work_done < quota) {
  587. work_done += flexcan_read_frame(dev);
  588. reg_iflag1 = flexcan_read(&regs->iflag1);
  589. }
  590. /* report bus errors */
  591. if (flexcan_has_and_handle_berr(priv, reg_esr) && work_done < quota)
  592. work_done += flexcan_poll_bus_err(dev, reg_esr);
  593. if (work_done < quota) {
  594. napi_complete(napi);
  595. /* enable IRQs */
  596. flexcan_write(FLEXCAN_IFLAG_DEFAULT, &regs->imask1);
  597. flexcan_write(priv->reg_ctrl_default, &regs->ctrl);
  598. }
  599. return work_done;
  600. }
  601. static irqreturn_t flexcan_irq(int irq, void *dev_id)
  602. {
  603. struct net_device *dev = dev_id;
  604. struct net_device_stats *stats = &dev->stats;
  605. struct flexcan_priv *priv = netdev_priv(dev);
  606. struct flexcan_regs __iomem *regs = priv->base;
  607. u32 reg_iflag1, reg_esr;
  608. reg_iflag1 = flexcan_read(&regs->iflag1);
  609. reg_esr = flexcan_read(&regs->esr);
  610. /* ACK all bus error and state change IRQ sources */
  611. if (reg_esr & FLEXCAN_ESR_ALL_INT)
  612. flexcan_write(reg_esr & FLEXCAN_ESR_ALL_INT, &regs->esr);
  613. /*
  614. * schedule NAPI in case of:
  615. * - rx IRQ
  616. * - state change IRQ
  617. * - bus error IRQ and bus error reporting is activated
  618. */
  619. if ((reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_AVAILABLE) ||
  620. (reg_esr & FLEXCAN_ESR_ERR_STATE) ||
  621. flexcan_has_and_handle_berr(priv, reg_esr)) {
  622. /*
  623. * The error bits are cleared on read,
  624. * save them for later use.
  625. */
  626. priv->reg_esr = reg_esr & FLEXCAN_ESR_ERR_BUS;
  627. flexcan_write(FLEXCAN_IFLAG_DEFAULT &
  628. ~FLEXCAN_IFLAG_RX_FIFO_AVAILABLE, &regs->imask1);
  629. flexcan_write(priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_ALL,
  630. &regs->ctrl);
  631. napi_schedule(&priv->napi);
  632. }
  633. /* FIFO overflow */
  634. if (reg_iflag1 & FLEXCAN_IFLAG_RX_FIFO_OVERFLOW) {
  635. flexcan_write(FLEXCAN_IFLAG_RX_FIFO_OVERFLOW, &regs->iflag1);
  636. dev->stats.rx_over_errors++;
  637. dev->stats.rx_errors++;
  638. }
  639. /* transmission complete interrupt */
  640. if (reg_iflag1 & (1 << FLEXCAN_TX_BUF_ID)) {
  641. stats->tx_bytes += can_get_echo_skb(dev, 0);
  642. stats->tx_packets++;
  643. can_led_event(dev, CAN_LED_EVENT_TX);
  644. /* after sending a RTR frame mailbox is in RX mode */
  645. flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
  646. &regs->cantxfg[FLEXCAN_TX_BUF_ID].can_ctrl);
  647. flexcan_write((1 << FLEXCAN_TX_BUF_ID), &regs->iflag1);
  648. netif_wake_queue(dev);
  649. }
  650. return IRQ_HANDLED;
  651. }
  652. static void flexcan_set_bittiming(struct net_device *dev)
  653. {
  654. const struct flexcan_priv *priv = netdev_priv(dev);
  655. const struct can_bittiming *bt = &priv->can.bittiming;
  656. struct flexcan_regs __iomem *regs = priv->base;
  657. u32 reg;
  658. reg = flexcan_read(&regs->ctrl);
  659. reg &= ~(FLEXCAN_CTRL_PRESDIV(0xff) |
  660. FLEXCAN_CTRL_RJW(0x3) |
  661. FLEXCAN_CTRL_PSEG1(0x7) |
  662. FLEXCAN_CTRL_PSEG2(0x7) |
  663. FLEXCAN_CTRL_PROPSEG(0x7) |
  664. FLEXCAN_CTRL_LPB |
  665. FLEXCAN_CTRL_SMP |
  666. FLEXCAN_CTRL_LOM);
  667. reg |= FLEXCAN_CTRL_PRESDIV(bt->brp - 1) |
  668. FLEXCAN_CTRL_PSEG1(bt->phase_seg1 - 1) |
  669. FLEXCAN_CTRL_PSEG2(bt->phase_seg2 - 1) |
  670. FLEXCAN_CTRL_RJW(bt->sjw - 1) |
  671. FLEXCAN_CTRL_PROPSEG(bt->prop_seg - 1);
  672. if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK)
  673. reg |= FLEXCAN_CTRL_LPB;
  674. if (priv->can.ctrlmode & CAN_CTRLMODE_LISTENONLY)
  675. reg |= FLEXCAN_CTRL_LOM;
  676. if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES)
  677. reg |= FLEXCAN_CTRL_SMP;
  678. netdev_info(dev, "writing ctrl=0x%08x\n", reg);
  679. flexcan_write(reg, &regs->ctrl);
  680. /* print chip status */
  681. netdev_dbg(dev, "%s: mcr=0x%08x ctrl=0x%08x\n", __func__,
  682. flexcan_read(&regs->mcr), flexcan_read(&regs->ctrl));
  683. }
  684. /*
  685. * flexcan_chip_start
  686. *
  687. * this functions is entered with clocks enabled
  688. *
  689. */
  690. static int flexcan_chip_start(struct net_device *dev)
  691. {
  692. struct flexcan_priv *priv = netdev_priv(dev);
  693. struct flexcan_regs __iomem *regs = priv->base;
  694. u32 reg_mcr, reg_ctrl, reg_crl2, reg_mecr;
  695. int err, i;
  696. /* enable module */
  697. err = flexcan_chip_enable(priv);
  698. if (err)
  699. return err;
  700. /* soft reset */
  701. err = flexcan_chip_softreset(priv);
  702. if (err)
  703. goto out_chip_disable;
  704. flexcan_set_bittiming(dev);
  705. /*
  706. * MCR
  707. *
  708. * enable freeze
  709. * enable fifo
  710. * halt now
  711. * only supervisor access
  712. * enable warning int
  713. * choose format C
  714. * disable local echo
  715. *
  716. */
  717. reg_mcr = flexcan_read(&regs->mcr);
  718. reg_mcr &= ~FLEXCAN_MCR_MAXMB(0xff);
  719. reg_mcr |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_FEN | FLEXCAN_MCR_HALT |
  720. FLEXCAN_MCR_SUPV | FLEXCAN_MCR_WRN_EN |
  721. FLEXCAN_MCR_IDAM_C | FLEXCAN_MCR_SRX_DIS |
  722. FLEXCAN_MCR_MAXMB(FLEXCAN_TX_BUF_ID);
  723. netdev_dbg(dev, "%s: writing mcr=0x%08x", __func__, reg_mcr);
  724. flexcan_write(reg_mcr, &regs->mcr);
  725. /*
  726. * CTRL
  727. *
  728. * disable timer sync feature
  729. *
  730. * disable auto busoff recovery
  731. * transmit lowest buffer first
  732. *
  733. * enable tx and rx warning interrupt
  734. * enable bus off interrupt
  735. * (== FLEXCAN_CTRL_ERR_STATE)
  736. */
  737. reg_ctrl = flexcan_read(&regs->ctrl);
  738. reg_ctrl &= ~FLEXCAN_CTRL_TSYN;
  739. reg_ctrl |= FLEXCAN_CTRL_BOFF_REC | FLEXCAN_CTRL_LBUF |
  740. FLEXCAN_CTRL_ERR_STATE;
  741. /*
  742. * enable the "error interrupt" (FLEXCAN_CTRL_ERR_MSK),
  743. * on most Flexcan cores, too. Otherwise we don't get
  744. * any error warning or passive interrupts.
  745. */
  746. if (priv->devtype_data->features & FLEXCAN_HAS_BROKEN_ERR_STATE ||
  747. priv->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING)
  748. reg_ctrl |= FLEXCAN_CTRL_ERR_MSK;
  749. else
  750. reg_ctrl &= ~FLEXCAN_CTRL_ERR_MSK;
  751. /* save for later use */
  752. priv->reg_ctrl_default = reg_ctrl;
  753. netdev_dbg(dev, "%s: writing ctrl=0x%08x", __func__, reg_ctrl);
  754. flexcan_write(reg_ctrl, &regs->ctrl);
  755. /* clear and invalidate all mailboxes first */
  756. for (i = FLEXCAN_TX_BUF_ID; i < ARRAY_SIZE(regs->cantxfg); i++) {
  757. flexcan_write(FLEXCAN_MB_CODE_RX_INACTIVE,
  758. &regs->cantxfg[i].can_ctrl);
  759. }
  760. /* Errata ERR005829: mark first TX mailbox as INACTIVE */
  761. flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
  762. &regs->cantxfg[FLEXCAN_TX_BUF_RESERVED].can_ctrl);
  763. /* mark TX mailbox as INACTIVE */
  764. flexcan_write(FLEXCAN_MB_CODE_TX_INACTIVE,
  765. &regs->cantxfg[FLEXCAN_TX_BUF_ID].can_ctrl);
  766. /* acceptance mask/acceptance code (accept everything) */
  767. flexcan_write(0x0, &regs->rxgmask);
  768. flexcan_write(0x0, &regs->rx14mask);
  769. flexcan_write(0x0, &regs->rx15mask);
  770. if (priv->devtype_data->features & FLEXCAN_HAS_V10_FEATURES)
  771. flexcan_write(0x0, &regs->rxfgmask);
  772. /*
  773. * On Vybrid, disable memory error detection interrupts
  774. * and freeze mode.
  775. * This also works around errata e5295 which generates
  776. * false positive memory errors and put the device in
  777. * freeze mode.
  778. */
  779. if (priv->devtype_data->features & FLEXCAN_HAS_MECR_FEATURES) {
  780. /*
  781. * Follow the protocol as described in "Detection
  782. * and Correction of Memory Errors" to write to
  783. * MECR register
  784. */
  785. reg_crl2 = flexcan_read(&regs->crl2);
  786. reg_crl2 |= FLEXCAN_CRL2_ECRWRE;
  787. flexcan_write(reg_crl2, &regs->crl2);
  788. reg_mecr = flexcan_read(&regs->mecr);
  789. reg_mecr &= ~FLEXCAN_MECR_ECRWRDIS;
  790. flexcan_write(reg_mecr, &regs->mecr);
  791. reg_mecr &= ~(FLEXCAN_MECR_NCEFAFRZ | FLEXCAN_MECR_HANCEI_MSK |
  792. FLEXCAN_MECR_FANCEI_MSK);
  793. flexcan_write(reg_mecr, &regs->mecr);
  794. }
  795. err = flexcan_transceiver_enable(priv);
  796. if (err)
  797. goto out_chip_disable;
  798. /* synchronize with the can bus */
  799. err = flexcan_chip_unfreeze(priv);
  800. if (err)
  801. goto out_transceiver_disable;
  802. priv->can.state = CAN_STATE_ERROR_ACTIVE;
  803. /* enable FIFO interrupts */
  804. flexcan_write(FLEXCAN_IFLAG_DEFAULT, &regs->imask1);
  805. /* print chip status */
  806. netdev_dbg(dev, "%s: reading mcr=0x%08x ctrl=0x%08x\n", __func__,
  807. flexcan_read(&regs->mcr), flexcan_read(&regs->ctrl));
  808. return 0;
  809. out_transceiver_disable:
  810. flexcan_transceiver_disable(priv);
  811. out_chip_disable:
  812. flexcan_chip_disable(priv);
  813. return err;
  814. }
  815. /*
  816. * flexcan_chip_stop
  817. *
  818. * this functions is entered with clocks enabled
  819. *
  820. */
  821. static void flexcan_chip_stop(struct net_device *dev)
  822. {
  823. struct flexcan_priv *priv = netdev_priv(dev);
  824. struct flexcan_regs __iomem *regs = priv->base;
  825. /* freeze + disable module */
  826. flexcan_chip_freeze(priv);
  827. flexcan_chip_disable(priv);
  828. /* Disable all interrupts */
  829. flexcan_write(0, &regs->imask1);
  830. flexcan_write(priv->reg_ctrl_default & ~FLEXCAN_CTRL_ERR_ALL,
  831. &regs->ctrl);
  832. flexcan_transceiver_disable(priv);
  833. priv->can.state = CAN_STATE_STOPPED;
  834. return;
  835. }
  836. static int flexcan_open(struct net_device *dev)
  837. {
  838. struct flexcan_priv *priv = netdev_priv(dev);
  839. int err;
  840. err = clk_prepare_enable(priv->clk_ipg);
  841. if (err)
  842. return err;
  843. err = clk_prepare_enable(priv->clk_per);
  844. if (err)
  845. goto out_disable_ipg;
  846. err = open_candev(dev);
  847. if (err)
  848. goto out_disable_per;
  849. err = request_irq(dev->irq, flexcan_irq, IRQF_SHARED, dev->name, dev);
  850. if (err)
  851. goto out_close;
  852. /* start chip and queuing */
  853. err = flexcan_chip_start(dev);
  854. if (err)
  855. goto out_free_irq;
  856. can_led_event(dev, CAN_LED_EVENT_OPEN);
  857. napi_enable(&priv->napi);
  858. netif_start_queue(dev);
  859. return 0;
  860. out_free_irq:
  861. free_irq(dev->irq, dev);
  862. out_close:
  863. close_candev(dev);
  864. out_disable_per:
  865. clk_disable_unprepare(priv->clk_per);
  866. out_disable_ipg:
  867. clk_disable_unprepare(priv->clk_ipg);
  868. return err;
  869. }
  870. static int flexcan_close(struct net_device *dev)
  871. {
  872. struct flexcan_priv *priv = netdev_priv(dev);
  873. netif_stop_queue(dev);
  874. napi_disable(&priv->napi);
  875. flexcan_chip_stop(dev);
  876. free_irq(dev->irq, dev);
  877. clk_disable_unprepare(priv->clk_per);
  878. clk_disable_unprepare(priv->clk_ipg);
  879. close_candev(dev);
  880. can_led_event(dev, CAN_LED_EVENT_STOP);
  881. return 0;
  882. }
  883. static int flexcan_set_mode(struct net_device *dev, enum can_mode mode)
  884. {
  885. int err;
  886. switch (mode) {
  887. case CAN_MODE_START:
  888. err = flexcan_chip_start(dev);
  889. if (err)
  890. return err;
  891. netif_wake_queue(dev);
  892. break;
  893. default:
  894. return -EOPNOTSUPP;
  895. }
  896. return 0;
  897. }
  898. static const struct net_device_ops flexcan_netdev_ops = {
  899. .ndo_open = flexcan_open,
  900. .ndo_stop = flexcan_close,
  901. .ndo_start_xmit = flexcan_start_xmit,
  902. .ndo_change_mtu = can_change_mtu,
  903. };
  904. static int register_flexcandev(struct net_device *dev)
  905. {
  906. struct flexcan_priv *priv = netdev_priv(dev);
  907. struct flexcan_regs __iomem *regs = priv->base;
  908. u32 reg, err;
  909. err = clk_prepare_enable(priv->clk_ipg);
  910. if (err)
  911. return err;
  912. err = clk_prepare_enable(priv->clk_per);
  913. if (err)
  914. goto out_disable_ipg;
  915. /* select "bus clock", chip must be disabled */
  916. err = flexcan_chip_disable(priv);
  917. if (err)
  918. goto out_disable_per;
  919. reg = flexcan_read(&regs->ctrl);
  920. reg |= FLEXCAN_CTRL_CLK_SRC;
  921. flexcan_write(reg, &regs->ctrl);
  922. err = flexcan_chip_enable(priv);
  923. if (err)
  924. goto out_chip_disable;
  925. /* set freeze, halt and activate FIFO, restrict register access */
  926. reg = flexcan_read(&regs->mcr);
  927. reg |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_HALT |
  928. FLEXCAN_MCR_FEN | FLEXCAN_MCR_SUPV;
  929. flexcan_write(reg, &regs->mcr);
  930. /*
  931. * Currently we only support newer versions of this core
  932. * featuring a RX FIFO. Older cores found on some Coldfire
  933. * derivates are not yet supported.
  934. */
  935. reg = flexcan_read(&regs->mcr);
  936. if (!(reg & FLEXCAN_MCR_FEN)) {
  937. netdev_err(dev, "Could not enable RX FIFO, unsupported core\n");
  938. err = -ENODEV;
  939. goto out_chip_disable;
  940. }
  941. err = register_candev(dev);
  942. /* disable core and turn off clocks */
  943. out_chip_disable:
  944. flexcan_chip_disable(priv);
  945. out_disable_per:
  946. clk_disable_unprepare(priv->clk_per);
  947. out_disable_ipg:
  948. clk_disable_unprepare(priv->clk_ipg);
  949. return err;
  950. }
  951. static void unregister_flexcandev(struct net_device *dev)
  952. {
  953. unregister_candev(dev);
  954. }
  955. static const struct of_device_id flexcan_of_match[] = {
  956. { .compatible = "fsl,imx6q-flexcan", .data = &fsl_imx6q_devtype_data, },
  957. { .compatible = "fsl,imx28-flexcan", .data = &fsl_imx28_devtype_data, },
  958. { .compatible = "fsl,p1010-flexcan", .data = &fsl_p1010_devtype_data, },
  959. { .compatible = "fsl,vf610-flexcan", .data = &fsl_vf610_devtype_data, },
  960. { /* sentinel */ },
  961. };
  962. MODULE_DEVICE_TABLE(of, flexcan_of_match);
  963. static const struct platform_device_id flexcan_id_table[] = {
  964. { .name = "flexcan", .driver_data = (kernel_ulong_t)&fsl_p1010_devtype_data, },
  965. { /* sentinel */ },
  966. };
  967. MODULE_DEVICE_TABLE(platform, flexcan_id_table);
  968. static int flexcan_probe(struct platform_device *pdev)
  969. {
  970. const struct of_device_id *of_id;
  971. const struct flexcan_devtype_data *devtype_data;
  972. struct net_device *dev;
  973. struct flexcan_priv *priv;
  974. struct regulator *reg_xceiver;
  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. reg_xceiver = devm_regulator_get(&pdev->dev, "xceiver");
  981. if (PTR_ERR(reg_xceiver) == -EPROBE_DEFER)
  982. return -EPROBE_DEFER;
  983. else if (IS_ERR(reg_xceiver))
  984. reg_xceiver = NULL;
  985. if (pdev->dev.of_node)
  986. of_property_read_u32(pdev->dev.of_node,
  987. "clock-frequency", &clock_freq);
  988. if (!clock_freq) {
  989. clk_ipg = devm_clk_get(&pdev->dev, "ipg");
  990. if (IS_ERR(clk_ipg)) {
  991. dev_err(&pdev->dev, "no ipg clock defined\n");
  992. return PTR_ERR(clk_ipg);
  993. }
  994. clk_per = devm_clk_get(&pdev->dev, "per");
  995. if (IS_ERR(clk_per)) {
  996. dev_err(&pdev->dev, "no per clock defined\n");
  997. return PTR_ERR(clk_per);
  998. }
  999. clock_freq = clk_get_rate(clk_per);
  1000. }
  1001. mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  1002. irq = platform_get_irq(pdev, 0);
  1003. if (irq <= 0)
  1004. return -ENODEV;
  1005. base = devm_ioremap_resource(&pdev->dev, mem);
  1006. if (IS_ERR(base))
  1007. return PTR_ERR(base);
  1008. of_id = of_match_device(flexcan_of_match, &pdev->dev);
  1009. if (of_id) {
  1010. devtype_data = of_id->data;
  1011. } else if (platform_get_device_id(pdev)->driver_data) {
  1012. devtype_data = (struct flexcan_devtype_data *)
  1013. platform_get_device_id(pdev)->driver_data;
  1014. } else {
  1015. return -ENODEV;
  1016. }
  1017. dev = alloc_candev(sizeof(struct flexcan_priv), 1);
  1018. if (!dev)
  1019. return -ENOMEM;
  1020. dev->netdev_ops = &flexcan_netdev_ops;
  1021. dev->irq = irq;
  1022. dev->flags |= IFF_ECHO;
  1023. priv = netdev_priv(dev);
  1024. priv->can.clock.freq = clock_freq;
  1025. priv->can.bittiming_const = &flexcan_bittiming_const;
  1026. priv->can.do_set_mode = flexcan_set_mode;
  1027. priv->can.do_get_berr_counter = flexcan_get_berr_counter;
  1028. priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
  1029. CAN_CTRLMODE_LISTENONLY | CAN_CTRLMODE_3_SAMPLES |
  1030. CAN_CTRLMODE_BERR_REPORTING;
  1031. priv->base = base;
  1032. priv->clk_ipg = clk_ipg;
  1033. priv->clk_per = clk_per;
  1034. priv->pdata = dev_get_platdata(&pdev->dev);
  1035. priv->devtype_data = devtype_data;
  1036. priv->reg_xceiver = reg_xceiver;
  1037. netif_napi_add(dev, &priv->napi, flexcan_poll, FLEXCAN_NAPI_WEIGHT);
  1038. platform_set_drvdata(pdev, dev);
  1039. SET_NETDEV_DEV(dev, &pdev->dev);
  1040. err = register_flexcandev(dev);
  1041. if (err) {
  1042. dev_err(&pdev->dev, "registering netdev failed\n");
  1043. goto failed_register;
  1044. }
  1045. devm_can_led_init(dev);
  1046. dev_info(&pdev->dev, "device registered (reg_base=%p, irq=%d)\n",
  1047. priv->base, dev->irq);
  1048. return 0;
  1049. failed_register:
  1050. free_candev(dev);
  1051. return err;
  1052. }
  1053. static int flexcan_remove(struct platform_device *pdev)
  1054. {
  1055. struct net_device *dev = platform_get_drvdata(pdev);
  1056. struct flexcan_priv *priv = netdev_priv(dev);
  1057. unregister_flexcandev(dev);
  1058. netif_napi_del(&priv->napi);
  1059. free_candev(dev);
  1060. return 0;
  1061. }
  1062. static int __maybe_unused flexcan_suspend(struct device *device)
  1063. {
  1064. struct net_device *dev = dev_get_drvdata(device);
  1065. struct flexcan_priv *priv = netdev_priv(dev);
  1066. int err;
  1067. err = flexcan_chip_disable(priv);
  1068. if (err)
  1069. return err;
  1070. if (netif_running(dev)) {
  1071. netif_stop_queue(dev);
  1072. netif_device_detach(dev);
  1073. }
  1074. priv->can.state = CAN_STATE_SLEEPING;
  1075. return 0;
  1076. }
  1077. static int __maybe_unused flexcan_resume(struct device *device)
  1078. {
  1079. struct net_device *dev = dev_get_drvdata(device);
  1080. struct flexcan_priv *priv = netdev_priv(dev);
  1081. priv->can.state = CAN_STATE_ERROR_ACTIVE;
  1082. if (netif_running(dev)) {
  1083. netif_device_attach(dev);
  1084. netif_start_queue(dev);
  1085. }
  1086. return flexcan_chip_enable(priv);
  1087. }
  1088. static SIMPLE_DEV_PM_OPS(flexcan_pm_ops, flexcan_suspend, flexcan_resume);
  1089. static struct platform_driver flexcan_driver = {
  1090. .driver = {
  1091. .name = DRV_NAME,
  1092. .pm = &flexcan_pm_ops,
  1093. .of_match_table = flexcan_of_match,
  1094. },
  1095. .probe = flexcan_probe,
  1096. .remove = flexcan_remove,
  1097. .id_table = flexcan_id_table,
  1098. };
  1099. module_platform_driver(flexcan_driver);
  1100. MODULE_AUTHOR("Sascha Hauer <kernel@pengutronix.de>, "
  1101. "Marc Kleine-Budde <kernel@pengutronix.de>");
  1102. MODULE_LICENSE("GPL v2");
  1103. MODULE_DESCRIPTION("CAN port driver for flexcan based chip");