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1// SPDX-License-Identifier: GPL-2.0-only2/* Copyright (C) 2007, 2011 Wolfgang Grandegger <wg@grandegger.com>3 * Copyright (C) 2012 Stephane Grosjean <s.grosjean@peak-system.com>4 *5 * Derived from the PCAN project file driver/src/pcan_pci.c:6 *7 * Copyright (C) 2001-2006  PEAK System-Technik GmbH8 */9 10#include <linux/kernel.h>11#include <linux/module.h>12#include <linux/interrupt.h>13#include <linux/netdevice.h>14#include <linux/delay.h>15#include <linux/pci.h>16#include <linux/io.h>17#include <linux/can.h>18#include <linux/can/dev.h>19 20#include "peak_canfd_user.h"21 22MODULE_AUTHOR("Stephane Grosjean <s.grosjean@peak-system.com>");23MODULE_DESCRIPTION("Socket-CAN driver for PEAK PCAN PCIe/M.2 FD family cards");24MODULE_LICENSE("GPL v2");25 26#define PCIEFD_DRV_NAME		"peak_pciefd"27 28#define PEAK_PCI_VENDOR_ID	0x001c	/* The PCI device and vendor IDs */29#define PEAK_PCIEFD_ID		0x0013	/* for PCIe slot cards */30#define PCAN_CPCIEFD_ID		0x0014	/* for Compact-PCI Serial slot cards */31#define PCAN_PCIE104FD_ID	0x0017	/* for PCIe-104 Express slot cards */32#define PCAN_MINIPCIEFD_ID      0x0018	/* for mini-PCIe slot cards */33#define PCAN_PCIEFD_OEM_ID      0x0019	/* for PCIe slot OEM cards */34#define PCAN_M2_ID		0x001a	/* for M2 slot cards */35 36/* PEAK PCIe board access description */37#define PCIEFD_BAR0_SIZE		(64 * 1024)38#define PCIEFD_RX_DMA_SIZE		(4 * 1024)39#define PCIEFD_TX_DMA_SIZE		(4 * 1024)40 41#define PCIEFD_TX_PAGE_SIZE		(2 * 1024)42 43/* System Control Registers */44#define PCIEFD_REG_SYS_CTL_SET		0x0000	/* set bits */45#define PCIEFD_REG_SYS_CTL_CLR		0x0004	/* clear bits */46 47/* Version info registers */48#define PCIEFD_REG_SYS_VER1		0x0040	/* version reg #1 */49#define PCIEFD_REG_SYS_VER2		0x0044	/* version reg #2 */50 51#define PCIEFD_FW_VERSION(x, y, z)	(((u32)(x) << 24) | \52					 ((u32)(y) << 16) | \53					 ((u32)(z) << 8))54 55/* System Control Registers Bits */56#define PCIEFD_SYS_CTL_TS_RST		0x00000001	/* timestamp clock */57#define PCIEFD_SYS_CTL_CLK_EN		0x00000002	/* system clock */58 59/* CAN-FD channel addresses */60#define PCIEFD_CANX_OFF(c)		(((c) + 1) * 0x1000)61 62#define PCIEFD_ECHO_SKB_MAX		PCANFD_ECHO_SKB_DEF63 64/* CAN-FD channel registers */65#define PCIEFD_REG_CAN_MISC		0x0000	/* Misc. control */66#define PCIEFD_REG_CAN_CLK_SEL		0x0008	/* Clock selector */67#define PCIEFD_REG_CAN_CMD_PORT_L	0x0010	/* 64-bits command port */68#define PCIEFD_REG_CAN_CMD_PORT_H	0x001469#define PCIEFD_REG_CAN_TX_REQ_ACC	0x0020	/* Tx request accumulator */70#define PCIEFD_REG_CAN_TX_CTL_SET	0x0030	/* Tx control set register */71#define PCIEFD_REG_CAN_TX_CTL_CLR	0x0038	/* Tx control clear register */72#define PCIEFD_REG_CAN_TX_DMA_ADDR_L	0x0040	/* 64-bits addr for Tx DMA */73#define PCIEFD_REG_CAN_TX_DMA_ADDR_H	0x004474#define PCIEFD_REG_CAN_RX_CTL_SET	0x0050	/* Rx control set register */75#define PCIEFD_REG_CAN_RX_CTL_CLR	0x0058	/* Rx control clear register */76#define PCIEFD_REG_CAN_RX_CTL_WRT	0x0060	/* Rx control write register */77#define PCIEFD_REG_CAN_RX_CTL_ACK	0x0068	/* Rx control ACK register */78#define PCIEFD_REG_CAN_RX_DMA_ADDR_L	0x0070	/* 64-bits addr for Rx DMA */79#define PCIEFD_REG_CAN_RX_DMA_ADDR_H	0x007480 81/* CAN-FD channel misc register bits */82#define CANFD_MISC_TS_RST		0x00000001	/* timestamp cnt rst */83 84/* CAN-FD channel Clock SELector Source & DIVider */85#define CANFD_CLK_SEL_DIV_MASK		0x0000000786#define CANFD_CLK_SEL_DIV_60MHZ		0x00000000	/* SRC=240MHz only */87#define CANFD_CLK_SEL_DIV_40MHZ		0x00000001	/* SRC=240MHz only */88#define CANFD_CLK_SEL_DIV_30MHZ		0x00000002	/* SRC=240MHz only */89#define CANFD_CLK_SEL_DIV_24MHZ		0x00000003	/* SRC=240MHz only */90#define CANFD_CLK_SEL_DIV_20MHZ		0x00000004	/* SRC=240MHz only */91 92#define CANFD_CLK_SEL_SRC_MASK		0x00000008	/* 0=80MHz, 1=240MHz */93#define CANFD_CLK_SEL_SRC_240MHZ	0x0000000894#define CANFD_CLK_SEL_SRC_80MHZ		(~CANFD_CLK_SEL_SRC_240MHZ & \95							CANFD_CLK_SEL_SRC_MASK)96 97#define CANFD_CLK_SEL_20MHZ		(CANFD_CLK_SEL_SRC_240MHZ |\98						CANFD_CLK_SEL_DIV_20MHZ)99#define CANFD_CLK_SEL_24MHZ		(CANFD_CLK_SEL_SRC_240MHZ |\100						CANFD_CLK_SEL_DIV_24MHZ)101#define CANFD_CLK_SEL_30MHZ		(CANFD_CLK_SEL_SRC_240MHZ |\102						CANFD_CLK_SEL_DIV_30MHZ)103#define CANFD_CLK_SEL_40MHZ		(CANFD_CLK_SEL_SRC_240MHZ |\104						CANFD_CLK_SEL_DIV_40MHZ)105#define CANFD_CLK_SEL_60MHZ		(CANFD_CLK_SEL_SRC_240MHZ |\106						CANFD_CLK_SEL_DIV_60MHZ)107#define CANFD_CLK_SEL_80MHZ		(CANFD_CLK_SEL_SRC_80MHZ)108 109/* CAN-FD channel Rx/Tx control register bits */110#define CANFD_CTL_UNC_BIT		0x00010000	/* Uncached DMA mem */111#define CANFD_CTL_RST_BIT		0x00020000	/* reset DMA action */112#define CANFD_CTL_IEN_BIT		0x00040000	/* IRQ enable */113 114/* Rx IRQ Count and Time Limits */115#define CANFD_CTL_IRQ_CL_DEF	16	/* Rx msg max nb per IRQ in Rx DMA */116#define CANFD_CTL_IRQ_TL_DEF	10	/* Time before IRQ if < CL (x100 µs) */117 118/* Tx anticipation window (link logical address should be aligned on 2K119 * boundary)120 */121#define PCIEFD_TX_PAGE_COUNT	(PCIEFD_TX_DMA_SIZE / PCIEFD_TX_PAGE_SIZE)122 123#define CANFD_MSG_LNK_TX	0x1001	/* Tx msgs link */124 125/* 32-bits IRQ status fields, heading Rx DMA area */126static inline int pciefd_irq_tag(u32 irq_status)127{128	return irq_status & 0x0000000f;129}130 131static inline int pciefd_irq_rx_cnt(u32 irq_status)132{133	return (irq_status & 0x000007f0) >> 4;134}135 136static inline int pciefd_irq_is_lnk(u32 irq_status)137{138	return irq_status & 0x00010000;139}140 141/* Rx record */142struct pciefd_rx_dma {143	__le32 irq_status;144	__le32 sys_time_low;145	__le32 sys_time_high;146	struct pucan_rx_msg msg[];147} __packed __aligned(4);148 149/* Tx Link record */150struct pciefd_tx_link {151	__le16 size;152	__le16 type;153	__le32 laddr_lo;154	__le32 laddr_hi;155} __packed __aligned(4);156 157/* Tx page descriptor */158struct pciefd_page {159	void *vbase;			/* page virtual address */160	dma_addr_t lbase;		/* page logical address */161	u32 offset;162	u32 size;163};164 165/* CAN-FD channel object */166struct pciefd_board;167struct pciefd_can {168	struct peak_canfd_priv ucan;	/* must be the first member */169	void __iomem *reg_base;		/* channel config base addr */170	struct pciefd_board *board;	/* reverse link */171 172	struct pucan_command pucan_cmd;	/* command buffer */173 174	dma_addr_t rx_dma_laddr;	/* DMA virtual and logical addr */175	void *rx_dma_vaddr;		/* for Rx and Tx areas */176	dma_addr_t tx_dma_laddr;177	void *tx_dma_vaddr;178 179	struct pciefd_page tx_pages[PCIEFD_TX_PAGE_COUNT];180	u16 tx_pages_free;		/* free Tx pages counter */181	u16 tx_page_index;		/* current page used for Tx */182	spinlock_t tx_lock;183 184	u32 irq_status;185	u32 irq_tag;				/* next irq tag */186};187 188/* PEAK-PCIe FD board object */189struct pciefd_board {190	void __iomem *reg_base;191	struct pci_dev *pci_dev;192	int can_count;193	spinlock_t cmd_lock;		/* 64-bits cmds must be atomic */194	struct pciefd_can *can[];	/* array of network devices */195};196 197/* supported device ids. */198static const struct pci_device_id peak_pciefd_tbl[] = {199	{PEAK_PCI_VENDOR_ID, PEAK_PCIEFD_ID, PCI_ANY_ID, PCI_ANY_ID,},200	{PEAK_PCI_VENDOR_ID, PCAN_CPCIEFD_ID, PCI_ANY_ID, PCI_ANY_ID,},201	{PEAK_PCI_VENDOR_ID, PCAN_PCIE104FD_ID, PCI_ANY_ID, PCI_ANY_ID,},202	{PEAK_PCI_VENDOR_ID, PCAN_MINIPCIEFD_ID, PCI_ANY_ID, PCI_ANY_ID,},203	{PEAK_PCI_VENDOR_ID, PCAN_PCIEFD_OEM_ID, PCI_ANY_ID, PCI_ANY_ID,},204	{PEAK_PCI_VENDOR_ID, PCAN_M2_ID, PCI_ANY_ID, PCI_ANY_ID,},205	{0,}206};207 208MODULE_DEVICE_TABLE(pci, peak_pciefd_tbl);209 210/* read a 32 bits value from a SYS block register */211static inline u32 pciefd_sys_readreg(const struct pciefd_board *priv, u16 reg)212{213	return readl(priv->reg_base + reg);214}215 216/* write a 32 bits value into a SYS block register */217static inline void pciefd_sys_writereg(const struct pciefd_board *priv,218				       u32 val, u16 reg)219{220	writel(val, priv->reg_base + reg);221}222 223/* read a 32 bits value from CAN-FD block register */224static inline u32 pciefd_can_readreg(const struct pciefd_can *priv, u16 reg)225{226	return readl(priv->reg_base + reg);227}228 229/* write a 32 bits value into a CAN-FD block register */230static inline void pciefd_can_writereg(const struct pciefd_can *priv,231				       u32 val, u16 reg)232{233	writel(val, priv->reg_base + reg);234}235 236/* give a channel logical Rx DMA address to the board */237static void pciefd_can_setup_rx_dma(struct pciefd_can *priv)238{239#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT240	const u32 dma_addr_h = (u32)(priv->rx_dma_laddr >> 32);241#else242	const u32 dma_addr_h = 0;243#endif244 245	/* (DMA must be reset for Rx) */246	pciefd_can_writereg(priv, CANFD_CTL_RST_BIT, PCIEFD_REG_CAN_RX_CTL_SET);247 248	/* write the logical address of the Rx DMA area for this channel */249	pciefd_can_writereg(priv, (u32)priv->rx_dma_laddr,250			    PCIEFD_REG_CAN_RX_DMA_ADDR_L);251	pciefd_can_writereg(priv, dma_addr_h, PCIEFD_REG_CAN_RX_DMA_ADDR_H);252 253	/* also indicates that Rx DMA is cacheable */254	pciefd_can_writereg(priv, CANFD_CTL_UNC_BIT, PCIEFD_REG_CAN_RX_CTL_CLR);255}256 257/* clear channel logical Rx DMA address from the board */258static void pciefd_can_clear_rx_dma(struct pciefd_can *priv)259{260	/* DMA must be reset for Rx */261	pciefd_can_writereg(priv, CANFD_CTL_RST_BIT, PCIEFD_REG_CAN_RX_CTL_SET);262 263	/* clear the logical address of the Rx DMA area for this channel */264	pciefd_can_writereg(priv, 0, PCIEFD_REG_CAN_RX_DMA_ADDR_L);265	pciefd_can_writereg(priv, 0, PCIEFD_REG_CAN_RX_DMA_ADDR_H);266}267 268/* give a channel logical Tx DMA address to the board */269static void pciefd_can_setup_tx_dma(struct pciefd_can *priv)270{271#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT272	const u32 dma_addr_h = (u32)(priv->tx_dma_laddr >> 32);273#else274	const u32 dma_addr_h = 0;275#endif276 277	/* (DMA must be reset for Tx) */278	pciefd_can_writereg(priv, CANFD_CTL_RST_BIT, PCIEFD_REG_CAN_TX_CTL_SET);279 280	/* write the logical address of the Tx DMA area for this channel */281	pciefd_can_writereg(priv, (u32)priv->tx_dma_laddr,282			    PCIEFD_REG_CAN_TX_DMA_ADDR_L);283	pciefd_can_writereg(priv, dma_addr_h, PCIEFD_REG_CAN_TX_DMA_ADDR_H);284 285	/* also indicates that Tx DMA is cacheable */286	pciefd_can_writereg(priv, CANFD_CTL_UNC_BIT, PCIEFD_REG_CAN_TX_CTL_CLR);287}288 289/* clear channel logical Tx DMA address from the board */290static void pciefd_can_clear_tx_dma(struct pciefd_can *priv)291{292	/* DMA must be reset for Tx */293	pciefd_can_writereg(priv, CANFD_CTL_RST_BIT, PCIEFD_REG_CAN_TX_CTL_SET);294 295	/* clear the logical address of the Tx DMA area for this channel */296	pciefd_can_writereg(priv, 0, PCIEFD_REG_CAN_TX_DMA_ADDR_L);297	pciefd_can_writereg(priv, 0, PCIEFD_REG_CAN_TX_DMA_ADDR_H);298}299 300static void pciefd_can_ack_rx_dma(struct pciefd_can *priv)301{302	/* read value of current IRQ tag and inc it for next one */303	priv->irq_tag = le32_to_cpu(*(__le32 *)priv->rx_dma_vaddr);304	priv->irq_tag++;305	priv->irq_tag &= 0xf;306 307	/* write the next IRQ tag for this CAN */308	pciefd_can_writereg(priv, priv->irq_tag, PCIEFD_REG_CAN_RX_CTL_ACK);309}310 311/* IRQ handler */312static irqreturn_t pciefd_irq_handler(int irq, void *arg)313{314	struct pciefd_can *priv = arg;315	struct pciefd_rx_dma *rx_dma = priv->rx_dma_vaddr;316 317	/* INTA mode only to sync with PCIe transaction */318	if (!pci_dev_msi_enabled(priv->board->pci_dev))319		(void)pciefd_sys_readreg(priv->board, PCIEFD_REG_SYS_VER1);320 321	/* read IRQ status from the first 32-bits of the Rx DMA area */322	priv->irq_status = le32_to_cpu(rx_dma->irq_status);323 324	/* check if this (shared) IRQ is for this CAN */325	if (pciefd_irq_tag(priv->irq_status) != priv->irq_tag)326		return IRQ_NONE;327 328	/* handle rx messages (if any) */329	peak_canfd_handle_msgs_list(&priv->ucan,330				    rx_dma->msg,331				    pciefd_irq_rx_cnt(priv->irq_status));332 333	/* handle tx link interrupt (if any) */334	if (pciefd_irq_is_lnk(priv->irq_status)) {335		unsigned long flags;336 337		spin_lock_irqsave(&priv->tx_lock, flags);338		priv->tx_pages_free++;339		spin_unlock_irqrestore(&priv->tx_lock, flags);340 341		/* wake producer up (only if enough room in echo_skb array) */342		spin_lock_irqsave(&priv->ucan.echo_lock, flags);343		if (!priv->ucan.can.echo_skb[priv->ucan.echo_idx])344			netif_wake_queue(priv->ucan.ndev);345 346		spin_unlock_irqrestore(&priv->ucan.echo_lock, flags);347	}348 349	/* re-enable Rx DMA transfer for this CAN */350	pciefd_can_ack_rx_dma(priv);351 352	return IRQ_HANDLED;353}354 355static int pciefd_enable_tx_path(struct peak_canfd_priv *ucan)356{357	struct pciefd_can *priv = (struct pciefd_can *)ucan;358	int i;359 360	/* initialize the Tx pages descriptors */361	priv->tx_pages_free = PCIEFD_TX_PAGE_COUNT - 1;362	priv->tx_page_index = 0;363 364	priv->tx_pages[0].vbase = priv->tx_dma_vaddr;365	priv->tx_pages[0].lbase = priv->tx_dma_laddr;366 367	for (i = 0; i < PCIEFD_TX_PAGE_COUNT; i++) {368		priv->tx_pages[i].offset = 0;369		priv->tx_pages[i].size = PCIEFD_TX_PAGE_SIZE -370					 sizeof(struct pciefd_tx_link);371		if (i) {372			priv->tx_pages[i].vbase =373					  priv->tx_pages[i - 1].vbase +374					  PCIEFD_TX_PAGE_SIZE;375			priv->tx_pages[i].lbase =376					  priv->tx_pages[i - 1].lbase +377					  PCIEFD_TX_PAGE_SIZE;378		}379	}380 381	/* setup Tx DMA addresses into IP core */382	pciefd_can_setup_tx_dma(priv);383 384	/* start (TX_RST=0) Tx Path */385	pciefd_can_writereg(priv, CANFD_CTL_RST_BIT, PCIEFD_REG_CAN_TX_CTL_CLR);386 387	return 0;388}389 390/* board specific CANFD command pre-processing */391static int pciefd_pre_cmd(struct peak_canfd_priv *ucan)392{393	struct pciefd_can *priv = (struct pciefd_can *)ucan;394	u16 cmd = pucan_cmd_get_opcode(&priv->pucan_cmd);395	int err;396 397	/* pre-process command */398	switch (cmd) {399	case PUCAN_CMD_NORMAL_MODE:400	case PUCAN_CMD_LISTEN_ONLY_MODE:401 402		if (ucan->can.state == CAN_STATE_BUS_OFF)403			break;404 405		/* going into operational mode: setup IRQ handler */406		err = request_irq(priv->ucan.ndev->irq,407				  pciefd_irq_handler,408				  IRQF_SHARED,409				  PCIEFD_DRV_NAME,410				  priv);411		if (err)412			return err;413 414		/* setup Rx DMA address */415		pciefd_can_setup_rx_dma(priv);416 417		/* setup max count of msgs per IRQ */418		pciefd_can_writereg(priv, (CANFD_CTL_IRQ_TL_DEF) << 8 |419				    CANFD_CTL_IRQ_CL_DEF,420				    PCIEFD_REG_CAN_RX_CTL_WRT);421 422		/* clear DMA RST for Rx (Rx start) */423		pciefd_can_writereg(priv, CANFD_CTL_RST_BIT,424				    PCIEFD_REG_CAN_RX_CTL_CLR);425 426		/* reset timestamps */427		pciefd_can_writereg(priv, !CANFD_MISC_TS_RST,428				    PCIEFD_REG_CAN_MISC);429 430		/* do an initial ACK */431		pciefd_can_ack_rx_dma(priv);432 433		/* enable IRQ for this CAN after having set next irq_tag */434		pciefd_can_writereg(priv, CANFD_CTL_IEN_BIT,435				    PCIEFD_REG_CAN_RX_CTL_SET);436 437		/* Tx path will be setup as soon as RX_BARRIER is received */438		break;439	default:440		break;441	}442 443	return 0;444}445 446/* write a command */447static int pciefd_write_cmd(struct peak_canfd_priv *ucan)448{449	struct pciefd_can *priv = (struct pciefd_can *)ucan;450	unsigned long flags;451 452	/* 64-bits command is atomic */453	spin_lock_irqsave(&priv->board->cmd_lock, flags);454 455	pciefd_can_writereg(priv, *(u32 *)ucan->cmd_buffer,456			    PCIEFD_REG_CAN_CMD_PORT_L);457	pciefd_can_writereg(priv, *(u32 *)(ucan->cmd_buffer + 4),458			    PCIEFD_REG_CAN_CMD_PORT_H);459 460	spin_unlock_irqrestore(&priv->board->cmd_lock, flags);461 462	return 0;463}464 465/* board specific CANFD command post-processing */466static int pciefd_post_cmd(struct peak_canfd_priv *ucan)467{468	struct pciefd_can *priv = (struct pciefd_can *)ucan;469	u16 cmd = pucan_cmd_get_opcode(&priv->pucan_cmd);470 471	switch (cmd) {472	case PUCAN_CMD_RESET_MODE:473 474		if (ucan->can.state == CAN_STATE_STOPPED)475			break;476 477		/* controller now in reset mode: */478 479		/* disable IRQ for this CAN */480		pciefd_can_writereg(priv, CANFD_CTL_IEN_BIT,481				    PCIEFD_REG_CAN_RX_CTL_CLR);482 483		/* stop and reset DMA addresses in Tx/Rx engines */484		pciefd_can_clear_tx_dma(priv);485		pciefd_can_clear_rx_dma(priv);486 487		/* wait for above commands to complete (read cycle) */488		(void)pciefd_sys_readreg(priv->board, PCIEFD_REG_SYS_VER1);489 490		free_irq(priv->ucan.ndev->irq, priv);491 492		ucan->can.state = CAN_STATE_STOPPED;493 494		break;495	}496 497	return 0;498}499 500static void *pciefd_alloc_tx_msg(struct peak_canfd_priv *ucan, u16 msg_size,501				 int *room_left)502{503	struct pciefd_can *priv = (struct pciefd_can *)ucan;504	struct pciefd_page *page = priv->tx_pages + priv->tx_page_index;505	unsigned long flags;506	void *msg;507 508	spin_lock_irqsave(&priv->tx_lock, flags);509 510	if (page->offset + msg_size > page->size) {511		struct pciefd_tx_link *lk;512 513		/* not enough space in this page: try another one */514		if (!priv->tx_pages_free) {515			spin_unlock_irqrestore(&priv->tx_lock, flags);516 517			/* Tx overflow */518			return NULL;519		}520 521		priv->tx_pages_free--;522 523		/* keep address of the very last free slot of current page */524		lk = page->vbase + page->offset;525 526		/* next, move on a new free page */527		priv->tx_page_index = (priv->tx_page_index + 1) %528				      PCIEFD_TX_PAGE_COUNT;529		page = priv->tx_pages + priv->tx_page_index;530 531		/* put link record to this new page at the end of prev one */532		lk->size = cpu_to_le16(sizeof(*lk));533		lk->type = cpu_to_le16(CANFD_MSG_LNK_TX);534		lk->laddr_lo = cpu_to_le32(page->lbase);535 536#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT537		lk->laddr_hi = cpu_to_le32(page->lbase >> 32);538#else539		lk->laddr_hi = 0;540#endif541		/* next msgs will be put from the begininng of this new page */542		page->offset = 0;543	}544 545	*room_left = priv->tx_pages_free * page->size;546 547	spin_unlock_irqrestore(&priv->tx_lock, flags);548 549	msg = page->vbase + page->offset;550 551	/* give back room left in the tx ring */552	*room_left += page->size - (page->offset + msg_size);553 554	return msg;555}556 557static int pciefd_write_tx_msg(struct peak_canfd_priv *ucan,558			       struct pucan_tx_msg *msg)559{560	struct pciefd_can *priv = (struct pciefd_can *)ucan;561	struct pciefd_page *page = priv->tx_pages + priv->tx_page_index;562 563	/* this slot is now reserved for writing the frame */564	page->offset += le16_to_cpu(msg->size);565 566	/* tell the board a frame has been written in Tx DMA area */567	pciefd_can_writereg(priv, 1, PCIEFD_REG_CAN_TX_REQ_ACC);568 569	return 0;570}571 572/* probe for CAN-FD channel #pciefd_board->can_count */573static int pciefd_can_probe(struct pciefd_board *pciefd)574{575	struct net_device *ndev;576	struct pciefd_can *priv;577	u32 clk;578	int err;579 580	/* allocate the candev object with default isize of echo skbs ring */581	ndev = alloc_peak_canfd_dev(sizeof(*priv), pciefd->can_count,582				    PCIEFD_ECHO_SKB_MAX);583	if (!ndev) {584		dev_err(&pciefd->pci_dev->dev,585			"failed to alloc candev object\n");586		goto failure;587	}588 589	priv = netdev_priv(ndev);590 591	/* fill-in candev private object: */592 593	/* setup PCIe-FD own callbacks */594	priv->ucan.pre_cmd = pciefd_pre_cmd;595	priv->ucan.write_cmd = pciefd_write_cmd;596	priv->ucan.post_cmd = pciefd_post_cmd;597	priv->ucan.enable_tx_path = pciefd_enable_tx_path;598	priv->ucan.alloc_tx_msg = pciefd_alloc_tx_msg;599	priv->ucan.write_tx_msg = pciefd_write_tx_msg;600 601	/* setup PCIe-FD own command buffer */602	priv->ucan.cmd_buffer = &priv->pucan_cmd;603	priv->ucan.cmd_maxlen = sizeof(priv->pucan_cmd);604 605	priv->board = pciefd;606 607	/* CAN config regs block address */608	priv->reg_base = pciefd->reg_base + PCIEFD_CANX_OFF(priv->ucan.index);609 610	/* allocate non-cacheable DMA'able 4KB memory area for Rx */611	priv->rx_dma_vaddr = dmam_alloc_coherent(&pciefd->pci_dev->dev,612						 PCIEFD_RX_DMA_SIZE,613						 &priv->rx_dma_laddr,614						 GFP_KERNEL);615	if (!priv->rx_dma_vaddr) {616		dev_err(&pciefd->pci_dev->dev,617			"Rx dmam_alloc_coherent(%u) failure\n",618			PCIEFD_RX_DMA_SIZE);619		goto err_free_candev;620	}621 622	/* allocate non-cacheable DMA'able 4KB memory area for Tx */623	priv->tx_dma_vaddr = dmam_alloc_coherent(&pciefd->pci_dev->dev,624						 PCIEFD_TX_DMA_SIZE,625						 &priv->tx_dma_laddr,626						 GFP_KERNEL);627	if (!priv->tx_dma_vaddr) {628		dev_err(&pciefd->pci_dev->dev,629			"Tx dmam_alloc_coherent(%u) failure\n",630			PCIEFD_TX_DMA_SIZE);631		goto err_free_candev;632	}633 634	/* CAN clock in RST mode */635	pciefd_can_writereg(priv, CANFD_MISC_TS_RST, PCIEFD_REG_CAN_MISC);636 637	/* read current clock value */638	clk = pciefd_can_readreg(priv, PCIEFD_REG_CAN_CLK_SEL);639	switch (clk) {640	case CANFD_CLK_SEL_20MHZ:641		priv->ucan.can.clock.freq = 20 * 1000 * 1000;642		break;643	case CANFD_CLK_SEL_24MHZ:644		priv->ucan.can.clock.freq = 24 * 1000 * 1000;645		break;646	case CANFD_CLK_SEL_30MHZ:647		priv->ucan.can.clock.freq = 30 * 1000 * 1000;648		break;649	case CANFD_CLK_SEL_40MHZ:650		priv->ucan.can.clock.freq = 40 * 1000 * 1000;651		break;652	case CANFD_CLK_SEL_60MHZ:653		priv->ucan.can.clock.freq = 60 * 1000 * 1000;654		break;655	default:656		pciefd_can_writereg(priv, CANFD_CLK_SEL_80MHZ,657				    PCIEFD_REG_CAN_CLK_SEL);658 659		fallthrough;660	case CANFD_CLK_SEL_80MHZ:661		priv->ucan.can.clock.freq = 80 * 1000 * 1000;662		break;663	}664 665	ndev->irq = pciefd->pci_dev->irq;666 667	SET_NETDEV_DEV(ndev, &pciefd->pci_dev->dev);668 669	err = register_candev(ndev);670	if (err) {671		dev_err(&pciefd->pci_dev->dev,672			"couldn't register CAN device: %d\n", err);673		goto err_free_candev;674	}675 676	spin_lock_init(&priv->tx_lock);677 678	/* save the object address in the board structure */679	pciefd->can[pciefd->can_count] = priv;680 681	dev_info(&pciefd->pci_dev->dev, "%s at reg_base=0x%p irq=%d\n",682		 ndev->name, priv->reg_base, ndev->irq);683 684	return 0;685 686err_free_candev:687	free_candev(ndev);688 689failure:690	return -ENOMEM;691}692 693/* remove a CAN-FD channel by releasing all of its resources */694static void pciefd_can_remove(struct pciefd_can *priv)695{696	/* unregister (close) the can device to go back to RST mode first */697	unregister_candev(priv->ucan.ndev);698 699	/* finally, free the candev object */700	free_candev(priv->ucan.ndev);701}702 703/* remove all CAN-FD channels by releasing their own resources */704static void pciefd_can_remove_all(struct pciefd_board *pciefd)705{706	while (pciefd->can_count > 0)707		pciefd_can_remove(pciefd->can[--pciefd->can_count]);708}709 710/* probe for the entire device */711static int peak_pciefd_probe(struct pci_dev *pdev,712			     const struct pci_device_id *ent)713{714	struct pciefd_board *pciefd;715	int err, can_count;716	u16 sub_sys_id;717	u8 hw_ver_major;718	u8 hw_ver_minor;719	u8 hw_ver_sub;720	u32 v2;721 722	err = pci_enable_device(pdev);723	if (err)724		return err;725	err = pci_request_regions(pdev, PCIEFD_DRV_NAME);726	if (err)727		goto err_disable_pci;728 729	/* the number of channels depends on sub-system id */730	err = pci_read_config_word(pdev, PCI_SUBSYSTEM_ID, &sub_sys_id);731	if (err)732		goto err_release_regions;733 734	dev_dbg(&pdev->dev, "probing device %04x:%04x:%04x\n",735		pdev->vendor, pdev->device, sub_sys_id);736 737	if (sub_sys_id >= 0x0012)738		can_count = 4;739	else if (sub_sys_id >= 0x0010)740		can_count = 3;741	else if (sub_sys_id >= 0x0004)742		can_count = 2;743	else744		can_count = 1;745 746	/* allocate board structure object */747	pciefd = devm_kzalloc(&pdev->dev, struct_size(pciefd, can, can_count),748			      GFP_KERNEL);749	if (!pciefd) {750		err = -ENOMEM;751		goto err_release_regions;752	}753 754	/* initialize the board structure */755	pciefd->pci_dev = pdev;756	spin_lock_init(&pciefd->cmd_lock);757 758	/* save the PCI BAR0 virtual address for further system regs access */759	pciefd->reg_base = pci_iomap(pdev, 0, PCIEFD_BAR0_SIZE);760	if (!pciefd->reg_base) {761		dev_err(&pdev->dev, "failed to map PCI resource #0\n");762		err = -ENOMEM;763		goto err_release_regions;764	}765 766	/* read the firmware version number */767	v2 = pciefd_sys_readreg(pciefd, PCIEFD_REG_SYS_VER2);768 769	hw_ver_major = (v2 & 0x0000f000) >> 12;770	hw_ver_minor = (v2 & 0x00000f00) >> 8;771	hw_ver_sub = (v2 & 0x000000f0) >> 4;772 773	dev_info(&pdev->dev,774		 "%ux CAN-FD PCAN-PCIe FPGA v%u.%u.%u:\n", can_count,775		 hw_ver_major, hw_ver_minor, hw_ver_sub);776 777#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT778	/* FW < v3.3.0 DMA logic doesn't handle correctly the mix of 32-bit and779	 * 64-bit logical addresses: this workaround forces usage of 32-bit780	 * DMA addresses only when such a fw is detected.781	 */782	if (PCIEFD_FW_VERSION(hw_ver_major, hw_ver_minor, hw_ver_sub) <783	    PCIEFD_FW_VERSION(3, 3, 0)) {784		err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));785		if (err)786			dev_warn(&pdev->dev,787				 "warning: can't set DMA mask %llxh (err %d)\n",788				 DMA_BIT_MASK(32), err);789	}790#endif791 792	/* stop system clock */793	pciefd_sys_writereg(pciefd, PCIEFD_SYS_CTL_CLK_EN,794			    PCIEFD_REG_SYS_CTL_CLR);795 796	pci_set_master(pdev);797 798	/* create now the corresponding channels objects */799	while (pciefd->can_count < can_count) {800		err = pciefd_can_probe(pciefd);801		if (err)802			goto err_free_canfd;803 804		pciefd->can_count++;805	}806 807	/* set system timestamps counter in RST mode */808	pciefd_sys_writereg(pciefd, PCIEFD_SYS_CTL_TS_RST,809			    PCIEFD_REG_SYS_CTL_SET);810 811	/* wait a bit (read cycle) */812	(void)pciefd_sys_readreg(pciefd, PCIEFD_REG_SYS_VER1);813 814	/* free all clocks */815	pciefd_sys_writereg(pciefd, PCIEFD_SYS_CTL_TS_RST,816			    PCIEFD_REG_SYS_CTL_CLR);817 818	/* start system clock */819	pciefd_sys_writereg(pciefd, PCIEFD_SYS_CTL_CLK_EN,820			    PCIEFD_REG_SYS_CTL_SET);821 822	/* remember the board structure address in the device user data */823	pci_set_drvdata(pdev, pciefd);824 825	return 0;826 827err_free_canfd:828	pciefd_can_remove_all(pciefd);829 830	pci_iounmap(pdev, pciefd->reg_base);831 832err_release_regions:833	pci_release_regions(pdev);834 835err_disable_pci:836	pci_disable_device(pdev);837 838	/* pci_xxx_config_word() return positive PCIBIOS_xxx error codes while839	 * the probe() function must return a negative errno in case of failure840	 * (err is unchanged if negative)841	 */842	return pcibios_err_to_errno(err);843}844 845/* free the board structure object, as well as its resources: */846static void peak_pciefd_remove(struct pci_dev *pdev)847{848	struct pciefd_board *pciefd = pci_get_drvdata(pdev);849 850	/* release CAN-FD channels resources */851	pciefd_can_remove_all(pciefd);852 853	pci_iounmap(pdev, pciefd->reg_base);854 855	pci_release_regions(pdev);856	pci_disable_device(pdev);857}858 859static struct pci_driver peak_pciefd_driver = {860	.name = PCIEFD_DRV_NAME,861	.id_table = peak_pciefd_tbl,862	.probe = peak_pciefd_probe,863	.remove = peak_pciefd_remove,864};865 866module_pci_driver(peak_pciefd_driver);867