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Release 4.16 drivers/net/can/peak_canfd/peak_pciefd_main.c

/*
 * Copyright (C) 2007, 2011 Wolfgang Grandegger <wg@grandegger.com>
 * Copyright (C) 2012 Stephane Grosjean <s.grosjean@peak-system.com>
 *
 * Derived from the PCAN project file driver/src/pcan_pci.c:
 *
 * Copyright (C) 2001-2006  PEAK System-Technik GmbH
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the version 2 of the GNU General Public License
 * as published by the Free Software Foundation
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>
#include <linux/delay.h>
#include <linux/pci.h>
#include <linux/io.h>
#include <linux/can.h>
#include <linux/can/dev.h>

#include "peak_canfd_user.h"

MODULE_AUTHOR("Stephane Grosjean <s.grosjean@peak-system.com>");
MODULE_DESCRIPTION("Socket-CAN driver for PEAK PCAN PCIe/M.2 FD family cards");
MODULE_SUPPORTED_DEVICE("PEAK PCAN PCIe/M.2 FD CAN cards");
MODULE_LICENSE("GPL v2");


#define PCIEFD_DRV_NAME		"peak_pciefd"


#define PEAK_PCI_VENDOR_ID	0x001c	
/* The PCI device and vendor IDs */

#define PEAK_PCIEFD_ID		0x0013	
/* for PCIe slot cards */

#define PCAN_CPCIEFD_ID		0x0014	
/* for Compact-PCI Serial slot cards */

#define PCAN_PCIE104FD_ID	0x0017	
/* for PCIe-104 Express slot cards */

#define PCAN_MINIPCIEFD_ID      0x0018	
/* for mini-PCIe slot cards */

#define PCAN_PCIEFD_OEM_ID      0x0019	
/* for PCIe slot OEM cards */

#define PCAN_M2_ID		0x001a	
/* for M2 slot cards */

/* PEAK PCIe board access description */

#define PCIEFD_BAR0_SIZE		(64 * 1024)

#define PCIEFD_RX_DMA_SIZE		(4 * 1024)

#define PCIEFD_TX_DMA_SIZE		(4 * 1024)


#define PCIEFD_TX_PAGE_SIZE		(2 * 1024)

/* System Control Registers */

#define PCIEFD_REG_SYS_CTL_SET		0x0000	
/* set bits */

#define PCIEFD_REG_SYS_CTL_CLR		0x0004	
/* clear bits */

/* Version info registers */

#define PCIEFD_REG_SYS_VER1		0x0040	
/* version reg #1 */

#define PCIEFD_REG_SYS_VER2		0x0044	
/* version reg #2 */

/* System Control Registers Bits */

#define PCIEFD_SYS_CTL_TS_RST		0x00000001	
/* timestamp clock */

#define PCIEFD_SYS_CTL_CLK_EN		0x00000002	
/* system clock */

/* CAN-FD channel addresses */

#define PCIEFD_CANX_OFF(c)		(((c) + 1) * 0x1000)


#define PCIEFD_ECHO_SKB_MAX		PCANFD_ECHO_SKB_DEF

/* CAN-FD channel registers */

#define PCIEFD_REG_CAN_MISC		0x0000	
/* Misc. control */

#define PCIEFD_REG_CAN_CLK_SEL		0x0008	
/* Clock selector */

#define PCIEFD_REG_CAN_CMD_PORT_L	0x0010	
/* 64-bits command port */

#define PCIEFD_REG_CAN_CMD_PORT_H	0x0014

#define PCIEFD_REG_CAN_TX_REQ_ACC	0x0020	
/* Tx request accumulator */

#define PCIEFD_REG_CAN_TX_CTL_SET	0x0030	
/* Tx control set register */

#define PCIEFD_REG_CAN_TX_CTL_CLR	0x0038	
/* Tx control clear register */

#define PCIEFD_REG_CAN_TX_DMA_ADDR_L	0x0040	
/* 64-bits addr for Tx DMA */

#define PCIEFD_REG_CAN_TX_DMA_ADDR_H	0x0044

#define PCIEFD_REG_CAN_RX_CTL_SET	0x0050	
/* Rx control set register */

#define PCIEFD_REG_CAN_RX_CTL_CLR	0x0058	
/* Rx control clear register */

#define PCIEFD_REG_CAN_RX_CTL_WRT	0x0060	
/* Rx control write register */

#define PCIEFD_REG_CAN_RX_CTL_ACK	0x0068	
/* Rx control ACK register */

#define PCIEFD_REG_CAN_RX_DMA_ADDR_L	0x0070	
/* 64-bits addr for Rx DMA */

#define PCIEFD_REG_CAN_RX_DMA_ADDR_H	0x0074

/* CAN-FD channel misc register bits */

#define CANFD_MISC_TS_RST		0x00000001	
/* timestamp cnt rst */

/* CAN-FD channel Clock SELector Source & DIVider */

#define CANFD_CLK_SEL_DIV_MASK		0x00000007

#define CANFD_CLK_SEL_DIV_60MHZ		0x00000000	
/* SRC=240MHz only */

#define CANFD_CLK_SEL_DIV_40MHZ		0x00000001	
/* SRC=240MHz only */

#define CANFD_CLK_SEL_DIV_30MHZ		0x00000002	
/* SRC=240MHz only */

#define CANFD_CLK_SEL_DIV_24MHZ		0x00000003	
/* SRC=240MHz only */

#define CANFD_CLK_SEL_DIV_20MHZ		0x00000004	
/* SRC=240MHz only */


#define CANFD_CLK_SEL_SRC_MASK		0x00000008	
/* 0=80MHz, 1=240MHz */

#define CANFD_CLK_SEL_SRC_240MHZ	0x00000008

#define CANFD_CLK_SEL_SRC_80MHZ		(~CANFD_CLK_SEL_SRC_240MHZ & \
                                                        CANFD_CLK_SEL_SRC_MASK)


#define CANFD_CLK_SEL_20MHZ		(CANFD_CLK_SEL_SRC_240MHZ |\
                                                CANFD_CLK_SEL_DIV_20MHZ)

#define CANFD_CLK_SEL_24MHZ		(CANFD_CLK_SEL_SRC_240MHZ |\
                                                CANFD_CLK_SEL_DIV_24MHZ)

#define CANFD_CLK_SEL_30MHZ		(CANFD_CLK_SEL_SRC_240MHZ |\
                                                CANFD_CLK_SEL_DIV_30MHZ)

#define CANFD_CLK_SEL_40MHZ		(CANFD_CLK_SEL_SRC_240MHZ |\
                                                CANFD_CLK_SEL_DIV_40MHZ)

#define CANFD_CLK_SEL_60MHZ		(CANFD_CLK_SEL_SRC_240MHZ |\
                                                CANFD_CLK_SEL_DIV_60MHZ)

#define CANFD_CLK_SEL_80MHZ		(CANFD_CLK_SEL_SRC_80MHZ)

/* CAN-FD channel Rx/Tx control register bits */

#define CANFD_CTL_UNC_BIT		0x00010000	
/* Uncached DMA mem */

#define CANFD_CTL_RST_BIT		0x00020000	
/* reset DMA action */

#define CANFD_CTL_IEN_BIT		0x00040000	
/* IRQ enable */

/* Rx IRQ Count and Time Limits */

#define CANFD_CTL_IRQ_CL_DEF	16	
/* Rx msg max nb per IRQ in Rx DMA */

#define CANFD_CTL_IRQ_TL_DEF	10	
/* Time before IRQ if < CL (x100 µs) */


#define CANFD_OPTIONS_SET	(CANFD_OPTION_ERROR | CANFD_OPTION_BUSLOAD)

/* Tx anticipation window (link logical address should be aligned on 2K
 * boundary)
 */

#define PCIEFD_TX_PAGE_COUNT	(PCIEFD_TX_DMA_SIZE / PCIEFD_TX_PAGE_SIZE)


#define CANFD_MSG_LNK_TX	0x1001	
/* Tx msgs link */

/* 32-bits IRQ status fields, heading Rx DMA area */

static inline int pciefd_irq_tag(u32 irq_status) { return irq_status & 0x0000000f; }

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static inline int pciefd_irq_rx_cnt(u32 irq_status) { return (irq_status & 0x000007f0) >> 4; }

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static inline int pciefd_irq_is_lnk(u32 irq_status) { return irq_status & 0x00010000; }

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/* Rx record */ struct pciefd_rx_dma { __le32 irq_status; __le32 sys_time_low; __le32 sys_time_high; struct pucan_rx_msg msg[0]; } __packed __aligned(4); /* Tx Link record */ struct pciefd_tx_link { __le16 size; __le16 type; __le32 laddr_lo; __le32 laddr_hi; } __packed __aligned(4); /* Tx page descriptor */ struct pciefd_page { void *vbase; /* page virtual address */ dma_addr_t lbase; /* page logical address */ u32 offset; u32 size; }; #define CANFD_IRQ_SET 0x00000001 #define CANFD_TX_PATH_SET 0x00000002 /* CAN-FD channel object */ struct pciefd_board; struct pciefd_can { struct peak_canfd_priv ucan; /* must be the first member */ void __iomem *reg_base; /* channel config base addr */ struct pciefd_board *board; /* reverse link */ struct pucan_command pucan_cmd; /* command buffer */ dma_addr_t rx_dma_laddr; /* DMA virtual and logical addr */ void *rx_dma_vaddr; /* for Rx and Tx areas */ dma_addr_t tx_dma_laddr; void *tx_dma_vaddr; struct pciefd_page tx_pages[PCIEFD_TX_PAGE_COUNT]; u16 tx_pages_free; /* free Tx pages counter */ u16 tx_page_index; /* current page used for Tx */ spinlock_t tx_lock; u32 irq_status; u32 irq_tag; /* next irq tag */ }; /* PEAK-PCIe FD board object */ struct pciefd_board { void __iomem *reg_base; struct pci_dev *pci_dev; int can_count; spinlock_t cmd_lock; /* 64-bits cmds must be atomic */ struct pciefd_can *can[0]; /* array of network devices */ }; /* supported device ids. */ static const struct pci_device_id peak_pciefd_tbl[] = { {PEAK_PCI_VENDOR_ID, PEAK_PCIEFD_ID, PCI_ANY_ID, PCI_ANY_ID,}, {PEAK_PCI_VENDOR_ID, PCAN_CPCIEFD_ID, PCI_ANY_ID, PCI_ANY_ID,}, {PEAK_PCI_VENDOR_ID, PCAN_PCIE104FD_ID, PCI_ANY_ID, PCI_ANY_ID,}, {PEAK_PCI_VENDOR_ID, PCAN_MINIPCIEFD_ID, PCI_ANY_ID, PCI_ANY_ID,}, {PEAK_PCI_VENDOR_ID, PCAN_PCIEFD_OEM_ID, PCI_ANY_ID, PCI_ANY_ID,}, {PEAK_PCI_VENDOR_ID, PCAN_M2_ID, PCI_ANY_ID, PCI_ANY_ID,}, {0,} }; MODULE_DEVICE_TABLE(pci, peak_pciefd_tbl); /* read a 32 bits value from a SYS block register */
static inline u32 pciefd_sys_readreg(const struct pciefd_board *priv, u16 reg) { return readl(priv->reg_base + reg); }

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/* write a 32 bits value into a SYS block register */
static inline void pciefd_sys_writereg(const struct pciefd_board *priv, u32 val, u16 reg) { writel(val, priv->reg_base + reg); }

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/* read a 32 bits value from CAN-FD block register */
static inline u32 pciefd_can_readreg(const struct pciefd_can *priv, u16 reg) { return readl(priv->reg_base + reg); }

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/* write a 32 bits value into a CAN-FD block register */
static inline void pciefd_can_writereg(const struct pciefd_can *priv, u32 val, u16 reg) { writel(val, priv->reg_base + reg); }

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/* give a channel logical Rx DMA address to the board */
static void pciefd_can_setup_rx_dma(struct pciefd_can *priv) { #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT const u32 dma_addr_h = (u32)(priv->rx_dma_laddr >> 32); #else const u32 dma_addr_h = 0; #endif /* (DMA must be reset for Rx) */ pciefd_can_writereg(priv, CANFD_CTL_RST_BIT, PCIEFD_REG_CAN_RX_CTL_SET); /* write the logical address of the Rx DMA area for this channel */ pciefd_can_writereg(priv, (u32)priv->rx_dma_laddr, PCIEFD_REG_CAN_RX_DMA_ADDR_L); pciefd_can_writereg(priv, dma_addr_h, PCIEFD_REG_CAN_RX_DMA_ADDR_H); /* also indicates that Rx DMA is cacheable */ pciefd_can_writereg(priv, CANFD_CTL_UNC_BIT, PCIEFD_REG_CAN_RX_CTL_CLR); }

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/* clear channel logical Rx DMA address from the board */
static void pciefd_can_clear_rx_dma(struct pciefd_can *priv) { /* DMA must be reset for Rx */ pciefd_can_writereg(priv, CANFD_CTL_RST_BIT, PCIEFD_REG_CAN_RX_CTL_SET); /* clear the logical address of the Rx DMA area for this channel */ pciefd_can_writereg(priv, 0, PCIEFD_REG_CAN_RX_DMA_ADDR_L); pciefd_can_writereg(priv, 0, PCIEFD_REG_CAN_RX_DMA_ADDR_H); }

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/* give a channel logical Tx DMA address to the board */
static void pciefd_can_setup_tx_dma(struct pciefd_can *priv) { #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT const u32 dma_addr_h = (u32)(priv->tx_dma_laddr >> 32); #else const u32 dma_addr_h = 0; #endif /* (DMA must be reset for Tx) */ pciefd_can_writereg(priv, CANFD_CTL_RST_BIT, PCIEFD_REG_CAN_TX_CTL_SET); /* write the logical address of the Tx DMA area for this channel */ pciefd_can_writereg(priv, (u32)priv->tx_dma_laddr, PCIEFD_REG_CAN_TX_DMA_ADDR_L); pciefd_can_writereg(priv, dma_addr_h, PCIEFD_REG_CAN_TX_DMA_ADDR_H); /* also indicates that Tx DMA is cacheable */ pciefd_can_writereg(priv, CANFD_CTL_UNC_BIT, PCIEFD_REG_CAN_TX_CTL_CLR); }

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/* clear channel logical Tx DMA address from the board */
static void pciefd_can_clear_tx_dma(struct pciefd_can *priv) { /* DMA must be reset for Tx */ pciefd_can_writereg(priv, CANFD_CTL_RST_BIT, PCIEFD_REG_CAN_TX_CTL_SET); /* clear the logical address of the Tx DMA area for this channel */ pciefd_can_writereg(priv, 0, PCIEFD_REG_CAN_TX_DMA_ADDR_L); pciefd_can_writereg(priv, 0, PCIEFD_REG_CAN_TX_DMA_ADDR_H); }

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static void pciefd_can_ack_rx_dma(struct pciefd_can *priv) { /* read value of current IRQ tag and inc it for next one */ priv->irq_tag = le32_to_cpu(*(__le32 *)priv->rx_dma_vaddr); priv->irq_tag++; priv->irq_tag &= 0xf; /* write the next IRQ tag for this CAN */ pciefd_can_writereg(priv, priv->irq_tag, PCIEFD_REG_CAN_RX_CTL_ACK); }

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/* IRQ handler */
static irqreturn_t pciefd_irq_handler(int irq, void *arg) { struct pciefd_can *priv = arg; struct pciefd_rx_dma *rx_dma = priv->rx_dma_vaddr; /* INTA mode only to sync with PCIe transaction */ if (!pci_dev_msi_enabled(priv->board->pci_dev)) (void)pciefd_sys_readreg(priv->board, PCIEFD_REG_SYS_VER1); /* read IRQ status from the first 32-bits of the Rx DMA area */ priv->irq_status = le32_to_cpu(rx_dma->irq_status); /* check if this (shared) IRQ is for this CAN */ if (pciefd_irq_tag(priv->irq_status) != priv->irq_tag) return IRQ_NONE; /* handle rx messages (if any) */ peak_canfd_handle_msgs_list(&priv->ucan, rx_dma->msg, pciefd_irq_rx_cnt(priv->irq_status)); /* handle tx link interrupt (if any) */ if (pciefd_irq_is_lnk(priv->irq_status)) { unsigned long flags; spin_lock_irqsave(&priv->tx_lock, flags); priv->tx_pages_free++; spin_unlock_irqrestore(&priv->tx_lock, flags); /* wake producer up (only if enough room in echo_skb array) */ spin_lock_irqsave(&priv->ucan.echo_lock, flags); if (!priv->ucan.can.echo_skb[priv->ucan.echo_idx]) netif_wake_queue(priv->ucan.ndev); spin_unlock_irqrestore(&priv->ucan.echo_lock, flags); } /* re-enable Rx DMA transfer for this CAN */ pciefd_can_ack_rx_dma(priv); return IRQ_HANDLED; }

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static int pciefd_enable_tx_path(struct peak_canfd_priv *ucan) { struct pciefd_can *priv = (struct pciefd_can *)ucan; int i; /* initialize the Tx pages descriptors */ priv->tx_pages_free = PCIEFD_TX_PAGE_COUNT - 1; priv->tx_page_index = 0; priv->tx_pages[0].vbase = priv->tx_dma_vaddr; priv->tx_pages[0].lbase = priv->tx_dma_laddr; for (i = 0; i < PCIEFD_TX_PAGE_COUNT; i++) { priv->tx_pages[i].offset = 0; priv->tx_pages[i].size = PCIEFD_TX_PAGE_SIZE - sizeof(struct pciefd_tx_link); if (i) { priv->tx_pages[i].vbase = priv->tx_pages[i - 1].vbase + PCIEFD_TX_PAGE_SIZE; priv->tx_pages[i].lbase = priv->tx_pages[i - 1].lbase + PCIEFD_TX_PAGE_SIZE; } } /* setup Tx DMA addresses into IP core */ pciefd_can_setup_tx_dma(priv); /* start (TX_RST=0) Tx Path */ pciefd_can_writereg(priv, CANFD_CTL_RST_BIT, PCIEFD_REG_CAN_TX_CTL_CLR); return 0; }

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/* board specific CANFD command pre-processing */
static int pciefd_pre_cmd(struct peak_canfd_priv *ucan) { struct pciefd_can *priv = (struct pciefd_can *)ucan; u16 cmd = pucan_cmd_get_opcode(&priv->pucan_cmd); int err; /* pre-process command */ switch (cmd) { case PUCAN_CMD_NORMAL_MODE: case PUCAN_CMD_LISTEN_ONLY_MODE: if (ucan->can.state == CAN_STATE_BUS_OFF) break; /* going into operational mode: setup IRQ handler */ err = request_irq(priv->board->pci_dev->irq, pciefd_irq_handler, IRQF_SHARED, PCIEFD_DRV_NAME, priv); if (err) return err; /* setup Rx DMA address */ pciefd_can_setup_rx_dma(priv); /* setup max count of msgs per IRQ */ pciefd_can_writereg(priv, (CANFD_CTL_IRQ_TL_DEF) << 8 | CANFD_CTL_IRQ_CL_DEF, PCIEFD_REG_CAN_RX_CTL_WRT); /* clear DMA RST for Rx (Rx start) */ pciefd_can_writereg(priv, CANFD_CTL_RST_BIT, PCIEFD_REG_CAN_RX_CTL_CLR); /* reset timestamps */ pciefd_can_writereg(priv, !CANFD_MISC_TS_RST, PCIEFD_REG_CAN_MISC); /* do an initial ACK */ pciefd_can_ack_rx_dma(priv); /* enable IRQ for this CAN after having set next irq_tag */ pciefd_can_writereg(priv, CANFD_CTL_IEN_BIT, PCIEFD_REG_CAN_RX_CTL_SET); /* Tx path will be setup as soon as RX_BARRIER is received */ break; default: break; } return 0; }

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/* write a command */
static int pciefd_write_cmd(struct peak_canfd_priv *ucan) { struct pciefd_can *priv = (struct pciefd_can *)ucan; unsigned long flags; /* 64-bits command is atomic */ spin_lock_irqsave(&priv->board->cmd_lock, flags); pciefd_can_writereg(priv, *(u32 *)ucan->cmd_buffer, PCIEFD_REG_CAN_CMD_PORT_L); pciefd_can_writereg(priv, *(u32 *)(ucan->cmd_buffer + 4), PCIEFD_REG_CAN_CMD_PORT_H); spin_unlock_irqrestore(&priv->board->cmd_lock, flags); return 0; }

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/* board specific CANFD command post-processing */
static int pciefd_post_cmd(struct peak_canfd_priv *ucan) { struct pciefd_can *priv = (struct pciefd_can *)ucan; u16 cmd = pucan_cmd_get_opcode(&priv->pucan_cmd); switch (cmd) { case PUCAN_CMD_RESET_MODE: if (ucan->can.state == CAN_STATE_STOPPED) break; /* controller now in reset mode: */ /* stop and reset DMA addresses in Tx/Rx engines */ pciefd_can_clear_tx_dma(priv); pciefd_can_clear_rx_dma(priv); /* disable IRQ for this CAN */ pciefd_can_writereg(priv, CANFD_CTL_IEN_BIT, PCIEFD_REG_CAN_RX_CTL_CLR); free_irq(priv->board->pci_dev->irq, priv); ucan->can.state = CAN_STATE_STOPPED; break; } return 0; }

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static void *pciefd_alloc_tx_msg(struct peak_canfd_priv *ucan, u16 msg_size, int *room_left) { struct pciefd_can *priv = (struct pciefd_can *)ucan; struct pciefd_page *page = priv->tx_pages + priv->tx_page_index; unsigned long flags; void *msg; spin_lock_irqsave(&priv->tx_lock, flags); if (page->offset + msg_size > page->size) { struct pciefd_tx_link *lk; /* not enough space in this page: try another one */ if (!priv->tx_pages_free) { spin_unlock_irqrestore(&priv->tx_lock, flags); /* Tx overflow */ return NULL; } priv->tx_pages_free--; /* keep address of the very last free slot of current page */ lk = page->vbase + page->offset; /* next, move on a new free page */ priv->tx_page_index = (priv->tx_page_index + 1) % PCIEFD_TX_PAGE_COUNT; page = priv->tx_pages + priv->tx_page_index; /* put link record to this new page at the end of prev one */ lk->size = cpu_to_le16(sizeof(*lk)); lk->type = cpu_to_le16(CANFD_MSG_LNK_TX); lk->laddr_lo = cpu_to_le32(page->lbase); #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT lk->laddr_hi = cpu_to_le32(page->lbase >> 32); #else lk->laddr_hi = 0; #endif /* next msgs will be put from the begininng of this new page */ page->offset = 0; } *room_left = priv->tx_pages_free * page->size; spin_unlock_irqrestore(&priv->tx_lock, flags); msg = page->vbase + page->offset; /* give back room left in the tx ring */ *room_left += page->size - (page->offset + msg_size); return msg; }

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static int pciefd_write_tx_msg(struct peak_canfd_priv *ucan, struct pucan_tx_msg *msg) { struct pciefd_can *priv = (struct pciefd_can *)ucan; struct pciefd_page *page = priv->tx_pages + priv->tx_page_index; /* this slot is now reserved for writing the frame */ page->offset += le16_to_cpu(msg->size); /* tell the board a frame has been written in Tx DMA area */ pciefd_can_writereg(priv, 1, PCIEFD_REG_CAN_TX_REQ_ACC); return 0; }

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/* probe for CAN-FD channel #pciefd_board->can_count */
static int pciefd_can_probe(struct pciefd_board *pciefd) { struct net_device *ndev; struct pciefd_can *priv; u32 clk; int err; /* allocate the candev object with default isize of echo skbs ring */ ndev = alloc_peak_canfd_dev(sizeof(*priv), pciefd->can_count, PCIEFD_ECHO_SKB_MAX); if (!ndev) { dev_err(&pciefd->pci_dev->dev, "failed to alloc candev object\n"); goto failure; } priv = netdev_priv(ndev); /* fill-in candev private object: */ /* setup PCIe-FD own callbacks */ priv->ucan.pre_cmd = pciefd_pre_cmd; priv->ucan.write_cmd = pciefd_write_cmd; priv->ucan.post_cmd = pciefd_post_cmd; priv->ucan.enable_tx_path = pciefd_enable_tx_path; priv->ucan.alloc_tx_msg = pciefd_alloc_tx_msg; priv->ucan.write_tx_msg = pciefd_write_tx_msg; /* setup PCIe-FD own command buffer */ priv->ucan.cmd_buffer = &priv->pucan_cmd; priv->ucan.cmd_maxlen = sizeof(priv->pucan_cmd); priv->board = pciefd; /* CAN config regs block address */ priv->reg_base = pciefd->reg_base + PCIEFD_CANX_OFF(priv->ucan.index); /* allocate non-cacheable DMA'able 4KB memory area for Rx */ priv->rx_dma_vaddr = dmam_alloc_coherent(&pciefd->pci_dev->dev, PCIEFD_RX_DMA_SIZE, &priv->rx_dma_laddr, GFP_KERNEL); if (!priv->rx_dma_vaddr) { dev_err(&pciefd->pci_dev->dev, "Rx dmam_alloc_coherent(%u) failure\n", PCIEFD_RX_DMA_SIZE); goto err_free_candev; } /* allocate non-cacheable DMA'able 4KB memory area for Tx */ priv->tx_dma_vaddr = dmam_alloc_coherent(&pciefd->pci_dev->dev, PCIEFD_TX_DMA_SIZE, &priv->tx_dma_laddr, GFP_KERNEL); if (!priv->tx_dma_vaddr) { dev_err(&pciefd->pci_dev->dev, "Tx dmaim_alloc_coherent(%u) failure\n", PCIEFD_TX_DMA_SIZE); goto err_free_candev; } /* CAN clock in RST mode */ pciefd_can_writereg(priv, CANFD_MISC_TS_RST, PCIEFD_REG_CAN_MISC); /* read current clock value */ clk = pciefd_can_readreg(priv, PCIEFD_REG_CAN_CLK_SEL); switch (clk) { case CANFD_CLK_SEL_20MHZ: priv->ucan.can.clock.freq = 20 * 1000 * 1000; break; case CANFD_CLK_SEL_24MHZ: priv->ucan.can.clock.freq = 24 * 1000 * 1000; break; case CANFD_CLK_SEL_30MHZ: priv->ucan.can.clock.freq = 30 * 1000 * 1000; break; case CANFD_CLK_SEL_40MHZ: priv->ucan.can.clock.freq = 40 * 1000 * 1000; break; case CANFD_CLK_SEL_60MHZ: priv->ucan.can.clock.freq = 60 * 1000 * 1000; break; default: pciefd_can_writereg(priv, CANFD_CLK_SEL_80MHZ, PCIEFD_REG_CAN_CLK_SEL); /* fallthough */ case CANFD_CLK_SEL_80MHZ: priv->ucan.can.clock.freq = 80 * 1000 * 1000; break; } ndev->irq = pciefd->pci_dev->irq; SET_NETDEV_DEV(ndev, &pciefd->pci_dev->dev); err = register_candev(ndev); if (err) { dev_err(&pciefd->pci_dev->dev, "couldn't register CAN device: %d\n", err); goto err_free_candev; } spin_lock_init(&priv->tx_lock); /* save the object address in the board structure */ pciefd->can[pciefd->can_count] = priv; dev_info(&pciefd->pci_dev->dev, "%s at reg_base=0x%p irq=%d\n", ndev->name, priv->reg_base, pciefd->pci_dev->irq); return 0; err_free_candev: free_candev(ndev); failure: return -ENOMEM; }

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Stephane Grosjean544100.00%1100.00%
Total544100.00%1100.00%

/* remove a CAN-FD channel by releasing all of its resources */
static void pciefd_can_remove(struct pciefd_can *priv) { /* unregister (close) the can device to go back to RST mode first */ unregister_candev(priv->ucan.ndev); /* finally, free the candev object */ free_candev(priv->ucan.ndev); }

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Stephane Grosjean31100.00%1100.00%
Total31100.00%1100.00%

/* remove all CAN-FD channels by releasing their own resources */
static void pciefd_can_remove_all(struct pciefd_board *pciefd) { while (pciefd->can_count > 0) pciefd_can_remove(pciefd->can[--pciefd->can_count]); }

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Stephane Grosjean32100.00%1100.00%
Total32100.00%1100.00%

/* probe for the entire device */
static int peak_pciefd_probe(struct pci_dev *pdev, const struct pci_device_id *ent) { struct pciefd_board *pciefd; int err, can_count; u16 sub_sys_id; u8 hw_ver_major; u8 hw_ver_minor; u8 hw_ver_sub; u32 v2; err = pci_enable_device(pdev); if (err) return err; err = pci_request_regions(pdev, PCIEFD_DRV_NAME); if (err) goto err_disable_pci; /* the number of channels depends on sub-system id */ err = pci_read_config_word(pdev, PCI_SUBSYSTEM_ID, &sub_sys_id); if (err) goto err_release_regions; dev_dbg(&pdev->dev, "probing device %04x:%04x:%04x\n", pdev->vendor, pdev->device, sub_sys_id); if (sub_sys_id >= 0x0012) can_count = 4; else if (sub_sys_id >= 0x0010) can_count = 3; else if (sub_sys_id >= 0x0004) can_count = 2; else can_count = 1; /* allocate board structure object */ pciefd = devm_kzalloc(&pdev->dev, sizeof(*pciefd) + can_count * sizeof(*pciefd->can), GFP_KERNEL); if (!pciefd) { err = -ENOMEM; goto err_release_regions; } /* initialize the board structure */ pciefd->pci_dev = pdev; spin_lock_init(&pciefd->cmd_lock); /* save the PCI BAR0 virtual address for further system regs access */ pciefd->reg_base = pci_iomap(pdev, 0, PCIEFD_BAR0_SIZE); if (!pciefd->reg_base) { dev_err(&pdev->dev, "failed to map PCI resource #0\n"); err = -ENOMEM; goto err_release_regions; } /* read the firmware version number */ v2 = pciefd_sys_readreg(pciefd, PCIEFD_REG_SYS_VER2); hw_ver_major = (v2 & 0x0000f000) >> 12; hw_ver_minor = (v2 & 0x00000f00) >> 8; hw_ver_sub = (v2 & 0x000000f0) >> 4; dev_info(&pdev->dev, "%ux CAN-FD PCAN-PCIe FPGA v%u.%u.%u:\n", can_count, hw_ver_major, hw_ver_minor, hw_ver_sub); /* stop system clock */ pciefd_sys_writereg(pciefd, PCIEFD_SYS_CTL_CLK_EN, PCIEFD_REG_SYS_CTL_CLR); pci_set_master(pdev); /* create now the corresponding channels objects */ while (pciefd->can_count < can_count) { err = pciefd_can_probe(pciefd); if (err) goto err_free_canfd; pciefd->can_count++; } /* set system timestamps counter in RST mode */ pciefd_sys_writereg(pciefd, PCIEFD_SYS_CTL_TS_RST, PCIEFD_REG_SYS_CTL_SET); /* wait a bit (read cycle) */ (void)pciefd_sys_readreg(pciefd, PCIEFD_REG_SYS_VER1); /* free all clocks */ pciefd_sys_writereg(pciefd, PCIEFD_SYS_CTL_TS_RST, PCIEFD_REG_SYS_CTL_CLR); /* start system clock */ pciefd_sys_writereg(pciefd, PCIEFD_SYS_CTL_CLK_EN, PCIEFD_REG_SYS_CTL_SET); /* remember the board structure address in the device user data */ pci_set_drvdata(pdev, pciefd); return 0; err_free_canfd: pciefd_can_remove_all(pciefd); pci_iounmap(pdev, pciefd->reg_base); err_release_regions: pci_release_regions(pdev); err_disable_pci: pci_disable_device(pdev); /* pci_xxx_config_word() return positive PCIBIOS_xxx error codes while * the probe() function must return a negative errno in case of failure * (err is unchanged if negative) */ return pcibios_err_to_errno(err); }

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Stephane Grosjean441100.00%2100.00%
Total441100.00%2100.00%

/* free the board structure object, as well as its resources: */
static void peak_pciefd_remove(struct pci_dev *pdev) { struct pciefd_board *pciefd = pci_get_drvdata(pdev); /* release CAN-FD channels resources */ pciefd_can_remove_all(pciefd); pci_iounmap(pdev, pciefd->reg_base); pci_release_regions(pdev); pci_disable_device(pdev); }

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Stephane Grosjean46100.00%1100.00%
Total46100.00%1100.00%

static struct pci_driver peak_pciefd_driver = { .name = PCIEFD_DRV_NAME, .id_table = peak_pciefd_tbl, .probe = peak_pciefd_probe, .remove = peak_pciefd_remove, }; module_pci_driver(peak_pciefd_driver);

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Stephane Grosjean3266100.00%4100.00%
Total3266100.00%4100.00%
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