diff options
Diffstat (limited to 'drivers/net/can/peak_canfd/peak_pciefd_main.c')
| -rw-r--r-- | drivers/net/can/peak_canfd/peak_pciefd_main.c | 866 |
1 files changed, 866 insertions, 0 deletions
diff --git a/drivers/net/can/peak_canfd/peak_pciefd_main.c b/drivers/net/can/peak_canfd/peak_pciefd_main.c new file mode 100644 index 000000000..1df3c4b54 --- /dev/null +++ b/drivers/net/can/peak_canfd/peak_pciefd_main.c @@ -0,0 +1,866 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* 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 + */ + +#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_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 */ + +#define PCIEFD_FW_VERSION(x, y, z) (((u32)(x) << 24) | \ + ((u32)(y) << 16) | \ + ((u32)(z) << 8)) + +/* 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) */ + +/* 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; +} + +static inline int pciefd_irq_rx_cnt(u32 irq_status) +{ + return (irq_status & 0x000007f0) >> 4; +} + +static inline int pciefd_irq_is_lnk(u32 irq_status) +{ + return irq_status & 0x00010000; +} + +/* Rx record */ +struct pciefd_rx_dma { + __le32 irq_status; + __le32 sys_time_low; + __le32 sys_time_high; + struct pucan_rx_msg msg[]; +} __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; +}; + +/* 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[]; /* 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); +} + +/* 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); +} + +/* 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); +} + +/* 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); +} + +/* 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); +} + +/* 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); +} + +/* 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); +} + +/* 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); +} + +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); +} + +/* 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; +} + +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; +} + +/* 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->ucan.ndev->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; +} + +/* 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; +} + +/* 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: */ + + /* disable IRQ for this CAN */ + pciefd_can_writereg(priv, CANFD_CTL_IEN_BIT, + PCIEFD_REG_CAN_RX_CTL_CLR); + + /* stop and reset DMA addresses in Tx/Rx engines */ + pciefd_can_clear_tx_dma(priv); + pciefd_can_clear_rx_dma(priv); + + /* wait for above commands to complete (read cycle) */ + (void)pciefd_sys_readreg(priv->board, PCIEFD_REG_SYS_VER1); + + free_irq(priv->ucan.ndev->irq, priv); + + ucan->can.state = CAN_STATE_STOPPED; + + break; + } + + return 0; +} + +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; +} + +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; +} + +/* 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 dmam_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); + + fallthrough; + 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, ndev->irq); + + return 0; + +err_free_candev: + free_candev(ndev); + +failure: + return -ENOMEM; +} + +/* 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); +} + +/* 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]); +} + +/* 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, struct_size(pciefd, can, can_count), + 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); + +#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT + /* FW < v3.3.0 DMA logic doesn't handle correctly the mix of 32-bit and + * 64-bit logical addresses: this workaround forces usage of 32-bit + * DMA addresses only when such a fw is detected. + */ + if (PCIEFD_FW_VERSION(hw_ver_major, hw_ver_minor, hw_ver_sub) < + PCIEFD_FW_VERSION(3, 3, 0)) { + err = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32)); + if (err) + dev_warn(&pdev->dev, + "warning: can't set DMA mask %llxh (err %d)\n", + DMA_BIT_MASK(32), err); + } +#endif + + /* 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); +} + +/* 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); +} + +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); |