diff options
Diffstat (limited to 'drivers/net/caif')
| -rw-r--r-- | drivers/net/caif/Kconfig | 56 | ||||
| -rw-r--r-- | drivers/net/caif/Makefile | 15 | ||||
| -rw-r--r-- | drivers/net/caif/caif_hsi.c | 1469 | ||||
| -rw-r--r-- | drivers/net/caif/caif_serial.c | 472 | ||||
| -rw-r--r-- | drivers/net/caif/caif_spi.c | 872 | ||||
| -rw-r--r-- | drivers/net/caif/caif_spi_slave.c | 254 | ||||
| -rw-r--r-- | drivers/net/caif/caif_virtio.c | 789 |
7 files changed, 3927 insertions, 0 deletions
diff --git a/drivers/net/caif/Kconfig b/drivers/net/caif/Kconfig new file mode 100644 index 000000000..f81df91a9 --- /dev/null +++ b/drivers/net/caif/Kconfig @@ -0,0 +1,56 @@ +# +# CAIF physical drivers +# + +comment "CAIF transport drivers" + +config CAIF_TTY + tristate "CAIF TTY transport driver" + depends on CAIF && TTY + default n + ---help--- + The CAIF TTY transport driver is a Line Discipline (ldisc) + identified as N_CAIF. When this ldisc is opened from user space + it will redirect the TTY's traffic into the CAIF stack. + +config CAIF_SPI_SLAVE + tristate "CAIF SPI transport driver for slave interface" + depends on CAIF && HAS_DMA + default n + ---help--- + The CAIF Link layer SPI Protocol driver for Slave SPI interface. + This driver implements a platform driver to accommodate for a + platform specific SPI device. A sample CAIF SPI Platform device is + provided in Documentation/networking/caif/spi_porting.txt + +config CAIF_SPI_SYNC + bool "Next command and length in start of frame" + depends on CAIF_SPI_SLAVE + default n + ---help--- + Putting the next command and length in the start of the frame can + help to synchronize to the next transfer in case of over or under-runs. + This option also needs to be enabled on the modem. + +config CAIF_HSI + tristate "CAIF HSI transport driver" + depends on CAIF + default n + ---help--- + The caif low level driver for CAIF over HSI. + Be aware that if you enable this then you also need to + enable a low-level HSI driver. + +config CAIF_VIRTIO + tristate "CAIF virtio transport driver" + depends on CAIF && HAS_DMA + select VHOST_RING + select VIRTIO + select GENERIC_ALLOCATOR + default n + ---help--- + The caif driver for CAIF over Virtio. + +if CAIF_VIRTIO +source "drivers/vhost/Kconfig.vringh" +endif diff --git a/drivers/net/caif/Makefile b/drivers/net/caif/Makefile new file mode 100644 index 000000000..54ae1165d --- /dev/null +++ b/drivers/net/caif/Makefile @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 +ccflags-$(CONFIG_CAIF_DEBUG) := -DDEBUG + +# Serial interface +obj-$(CONFIG_CAIF_TTY) += caif_serial.o + +# SPI slave physical interfaces module +cfspi_slave-objs := caif_spi.o caif_spi_slave.o +obj-$(CONFIG_CAIF_SPI_SLAVE) += cfspi_slave.o + +# HSI interface +obj-$(CONFIG_CAIF_HSI) += caif_hsi.o + +# Virtio interface +obj-$(CONFIG_CAIF_VIRTIO) += caif_virtio.o diff --git a/drivers/net/caif/caif_hsi.c b/drivers/net/caif/caif_hsi.c new file mode 100644 index 000000000..253a1bbe3 --- /dev/null +++ b/drivers/net/caif/caif_hsi.c @@ -0,0 +1,1469 @@ +/* + * Copyright (C) ST-Ericsson AB 2010 + * Author: Daniel Martensson + * Dmitry.Tarnyagin / dmitry.tarnyagin@lockless.no + * License terms: GNU General Public License (GPL) version 2. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME fmt + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/netdevice.h> +#include <linux/string.h> +#include <linux/list.h> +#include <linux/interrupt.h> +#include <linux/delay.h> +#include <linux/sched.h> +#include <linux/if_arp.h> +#include <linux/timer.h> +#include <net/rtnetlink.h> +#include <linux/pkt_sched.h> +#include <net/caif/caif_layer.h> +#include <net/caif/caif_hsi.h> + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Daniel Martensson"); +MODULE_DESCRIPTION("CAIF HSI driver"); + +/* Returns the number of padding bytes for alignment. */ +#define PAD_POW2(x, pow) ((((x)&((pow)-1)) == 0) ? 0 :\ + (((pow)-((x)&((pow)-1))))) + +static const struct cfhsi_config hsi_default_config = { + + /* Inactivity timeout on HSI, ms */ + .inactivity_timeout = HZ, + + /* Aggregation timeout (ms) of zero means no aggregation is done*/ + .aggregation_timeout = 1, + + /* + * HSI link layer flow-control thresholds. + * Threshold values for the HSI packet queue. Flow-control will be + * asserted when the number of packets exceeds q_high_mark. It will + * not be de-asserted before the number of packets drops below + * q_low_mark. + * Warning: A high threshold value might increase throughput but it + * will at the same time prevent channel prioritization and increase + * the risk of flooding the modem. The high threshold should be above + * the low. + */ + .q_high_mark = 100, + .q_low_mark = 50, + + /* + * HSI padding options. + * Warning: must be a base of 2 (& operation used) and can not be zero ! + */ + .head_align = 4, + .tail_align = 4, +}; + +#define ON 1 +#define OFF 0 + +static LIST_HEAD(cfhsi_list); + +static void cfhsi_inactivity_tout(struct timer_list *t) +{ + struct cfhsi *cfhsi = from_timer(cfhsi, t, inactivity_timer); + + netdev_dbg(cfhsi->ndev, "%s.\n", + __func__); + + /* Schedule power down work queue. */ + if (!test_bit(CFHSI_SHUTDOWN, &cfhsi->bits)) + queue_work(cfhsi->wq, &cfhsi->wake_down_work); +} + +static void cfhsi_update_aggregation_stats(struct cfhsi *cfhsi, + const struct sk_buff *skb, + int direction) +{ + struct caif_payload_info *info; + int hpad, tpad, len; + + info = (struct caif_payload_info *)&skb->cb; + hpad = 1 + PAD_POW2((info->hdr_len + 1), cfhsi->cfg.head_align); + tpad = PAD_POW2((skb->len + hpad), cfhsi->cfg.tail_align); + len = skb->len + hpad + tpad; + + if (direction > 0) + cfhsi->aggregation_len += len; + else if (direction < 0) + cfhsi->aggregation_len -= len; +} + +static bool cfhsi_can_send_aggregate(struct cfhsi *cfhsi) +{ + int i; + + if (cfhsi->cfg.aggregation_timeout == 0) + return true; + + for (i = 0; i < CFHSI_PRIO_BEBK; ++i) { + if (cfhsi->qhead[i].qlen) + return true; + } + + /* TODO: Use aggregation_len instead */ + if (cfhsi->qhead[CFHSI_PRIO_BEBK].qlen >= CFHSI_MAX_PKTS) + return true; + + return false; +} + +static struct sk_buff *cfhsi_dequeue(struct cfhsi *cfhsi) +{ + struct sk_buff *skb; + int i; + + for (i = 0; i < CFHSI_PRIO_LAST; ++i) { + skb = skb_dequeue(&cfhsi->qhead[i]); + if (skb) + break; + } + + return skb; +} + +static int cfhsi_tx_queue_len(struct cfhsi *cfhsi) +{ + int i, len = 0; + for (i = 0; i < CFHSI_PRIO_LAST; ++i) + len += skb_queue_len(&cfhsi->qhead[i]); + return len; +} + +static void cfhsi_abort_tx(struct cfhsi *cfhsi) +{ + struct sk_buff *skb; + + for (;;) { + spin_lock_bh(&cfhsi->lock); + skb = cfhsi_dequeue(cfhsi); + if (!skb) + break; + + cfhsi->ndev->stats.tx_errors++; + cfhsi->ndev->stats.tx_dropped++; + cfhsi_update_aggregation_stats(cfhsi, skb, -1); + spin_unlock_bh(&cfhsi->lock); + kfree_skb(skb); + } + cfhsi->tx_state = CFHSI_TX_STATE_IDLE; + if (!test_bit(CFHSI_SHUTDOWN, &cfhsi->bits)) + mod_timer(&cfhsi->inactivity_timer, + jiffies + cfhsi->cfg.inactivity_timeout); + spin_unlock_bh(&cfhsi->lock); +} + +static int cfhsi_flush_fifo(struct cfhsi *cfhsi) +{ + char buffer[32]; /* Any reasonable value */ + size_t fifo_occupancy; + int ret; + + netdev_dbg(cfhsi->ndev, "%s.\n", + __func__); + + do { + ret = cfhsi->ops->cfhsi_fifo_occupancy(cfhsi->ops, + &fifo_occupancy); + if (ret) { + netdev_warn(cfhsi->ndev, + "%s: can't get FIFO occupancy: %d.\n", + __func__, ret); + break; + } else if (!fifo_occupancy) + /* No more data, exitting normally */ + break; + + fifo_occupancy = min(sizeof(buffer), fifo_occupancy); + set_bit(CFHSI_FLUSH_FIFO, &cfhsi->bits); + ret = cfhsi->ops->cfhsi_rx(buffer, fifo_occupancy, + cfhsi->ops); + if (ret) { + clear_bit(CFHSI_FLUSH_FIFO, &cfhsi->bits); + netdev_warn(cfhsi->ndev, + "%s: can't read data: %d.\n", + __func__, ret); + break; + } + + ret = 5 * HZ; + ret = wait_event_interruptible_timeout(cfhsi->flush_fifo_wait, + !test_bit(CFHSI_FLUSH_FIFO, &cfhsi->bits), ret); + + if (ret < 0) { + netdev_warn(cfhsi->ndev, + "%s: can't wait for flush complete: %d.\n", + __func__, ret); + break; + } else if (!ret) { + ret = -ETIMEDOUT; + netdev_warn(cfhsi->ndev, + "%s: timeout waiting for flush complete.\n", + __func__); + break; + } + } while (1); + + return ret; +} + +static int cfhsi_tx_frm(struct cfhsi_desc *desc, struct cfhsi *cfhsi) +{ + int nfrms = 0; + int pld_len = 0; + struct sk_buff *skb; + u8 *pfrm = desc->emb_frm + CFHSI_MAX_EMB_FRM_SZ; + + skb = cfhsi_dequeue(cfhsi); + if (!skb) + return 0; + + /* Clear offset. */ + desc->offset = 0; + + /* Check if we can embed a CAIF frame. */ + if (skb->len < CFHSI_MAX_EMB_FRM_SZ) { + struct caif_payload_info *info; + int hpad; + int tpad; + + /* Calculate needed head alignment and tail alignment. */ + info = (struct caif_payload_info *)&skb->cb; + + hpad = 1 + PAD_POW2((info->hdr_len + 1), cfhsi->cfg.head_align); + tpad = PAD_POW2((skb->len + hpad), cfhsi->cfg.tail_align); + + /* Check if frame still fits with added alignment. */ + if ((skb->len + hpad + tpad) <= CFHSI_MAX_EMB_FRM_SZ) { + u8 *pemb = desc->emb_frm; + desc->offset = CFHSI_DESC_SHORT_SZ; + *pemb = (u8)(hpad - 1); + pemb += hpad; + + /* Update network statistics. */ + spin_lock_bh(&cfhsi->lock); + cfhsi->ndev->stats.tx_packets++; + cfhsi->ndev->stats.tx_bytes += skb->len; + cfhsi_update_aggregation_stats(cfhsi, skb, -1); + spin_unlock_bh(&cfhsi->lock); + + /* Copy in embedded CAIF frame. */ + skb_copy_bits(skb, 0, pemb, skb->len); + + /* Consume the SKB */ + consume_skb(skb); + skb = NULL; + } + } + + /* Create payload CAIF frames. */ + while (nfrms < CFHSI_MAX_PKTS) { + struct caif_payload_info *info; + int hpad; + int tpad; + + if (!skb) + skb = cfhsi_dequeue(cfhsi); + + if (!skb) + break; + + /* Calculate needed head alignment and tail alignment. */ + info = (struct caif_payload_info *)&skb->cb; + + hpad = 1 + PAD_POW2((info->hdr_len + 1), cfhsi->cfg.head_align); + tpad = PAD_POW2((skb->len + hpad), cfhsi->cfg.tail_align); + + /* Fill in CAIF frame length in descriptor. */ + desc->cffrm_len[nfrms] = hpad + skb->len + tpad; + + /* Fill head padding information. */ + *pfrm = (u8)(hpad - 1); + pfrm += hpad; + + /* Update network statistics. */ + spin_lock_bh(&cfhsi->lock); + cfhsi->ndev->stats.tx_packets++; + cfhsi->ndev->stats.tx_bytes += skb->len; + cfhsi_update_aggregation_stats(cfhsi, skb, -1); + spin_unlock_bh(&cfhsi->lock); + + /* Copy in CAIF frame. */ + skb_copy_bits(skb, 0, pfrm, skb->len); + + /* Update payload length. */ + pld_len += desc->cffrm_len[nfrms]; + + /* Update frame pointer. */ + pfrm += skb->len + tpad; + + /* Consume the SKB */ + consume_skb(skb); + skb = NULL; + + /* Update number of frames. */ + nfrms++; + } + + /* Unused length fields should be zero-filled (according to SPEC). */ + while (nfrms < CFHSI_MAX_PKTS) { + desc->cffrm_len[nfrms] = 0x0000; + nfrms++; + } + + /* Check if we can piggy-back another descriptor. */ + if (cfhsi_can_send_aggregate(cfhsi)) + desc->header |= CFHSI_PIGGY_DESC; + else + desc->header &= ~CFHSI_PIGGY_DESC; + + return CFHSI_DESC_SZ + pld_len; +} + +static void cfhsi_start_tx(struct cfhsi *cfhsi) +{ + struct cfhsi_desc *desc = (struct cfhsi_desc *)cfhsi->tx_buf; + int len, res; + + netdev_dbg(cfhsi->ndev, "%s.\n", __func__); + + if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits)) + return; + + do { + /* Create HSI frame. */ + len = cfhsi_tx_frm(desc, cfhsi); + if (!len) { + spin_lock_bh(&cfhsi->lock); + if (unlikely(cfhsi_tx_queue_len(cfhsi))) { + spin_unlock_bh(&cfhsi->lock); + res = -EAGAIN; + continue; + } + cfhsi->tx_state = CFHSI_TX_STATE_IDLE; + /* Start inactivity timer. */ + mod_timer(&cfhsi->inactivity_timer, + jiffies + cfhsi->cfg.inactivity_timeout); + spin_unlock_bh(&cfhsi->lock); + break; + } + + /* Set up new transfer. */ + res = cfhsi->ops->cfhsi_tx(cfhsi->tx_buf, len, cfhsi->ops); + if (WARN_ON(res < 0)) + netdev_err(cfhsi->ndev, "%s: TX error %d.\n", + __func__, res); + } while (res < 0); +} + +static void cfhsi_tx_done(struct cfhsi *cfhsi) +{ + netdev_dbg(cfhsi->ndev, "%s.\n", __func__); + + if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits)) + return; + + /* + * Send flow on if flow off has been previously signalled + * and number of packets is below low water mark. + */ + spin_lock_bh(&cfhsi->lock); + if (cfhsi->flow_off_sent && + cfhsi_tx_queue_len(cfhsi) <= cfhsi->cfg.q_low_mark && + cfhsi->cfdev.flowctrl) { + + cfhsi->flow_off_sent = 0; + cfhsi->cfdev.flowctrl(cfhsi->ndev, ON); + } + + if (cfhsi_can_send_aggregate(cfhsi)) { + spin_unlock_bh(&cfhsi->lock); + cfhsi_start_tx(cfhsi); + } else { + mod_timer(&cfhsi->aggregation_timer, + jiffies + cfhsi->cfg.aggregation_timeout); + spin_unlock_bh(&cfhsi->lock); + } + + return; +} + +static void cfhsi_tx_done_cb(struct cfhsi_cb_ops *cb_ops) +{ + struct cfhsi *cfhsi; + + cfhsi = container_of(cb_ops, struct cfhsi, cb_ops); + netdev_dbg(cfhsi->ndev, "%s.\n", + __func__); + + if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits)) + return; + cfhsi_tx_done(cfhsi); +} + +static int cfhsi_rx_desc(struct cfhsi_desc *desc, struct cfhsi *cfhsi) +{ + int xfer_sz = 0; + int nfrms = 0; + u16 *plen = NULL; + u8 *pfrm = NULL; + + if ((desc->header & ~CFHSI_PIGGY_DESC) || + (desc->offset > CFHSI_MAX_EMB_FRM_SZ)) { + netdev_err(cfhsi->ndev, "%s: Invalid descriptor.\n", + __func__); + return -EPROTO; + } + + /* Check for embedded CAIF frame. */ + if (desc->offset) { + struct sk_buff *skb; + int len = 0; + pfrm = ((u8 *)desc) + desc->offset; + + /* Remove offset padding. */ + pfrm += *pfrm + 1; + + /* Read length of CAIF frame (little endian). */ + len = *pfrm; + len |= ((*(pfrm+1)) << 8) & 0xFF00; + len += 2; /* Add FCS fields. */ + + /* Sanity check length of CAIF frame. */ + if (unlikely(len > CFHSI_MAX_CAIF_FRAME_SZ)) { + netdev_err(cfhsi->ndev, "%s: Invalid length.\n", + __func__); + return -EPROTO; + } + + /* Allocate SKB (OK even in IRQ context). */ + skb = alloc_skb(len + 1, GFP_ATOMIC); + if (!skb) { + netdev_err(cfhsi->ndev, "%s: Out of memory !\n", + __func__); + return -ENOMEM; + } + caif_assert(skb != NULL); + + skb_put_data(skb, pfrm, len); + + skb->protocol = htons(ETH_P_CAIF); + skb_reset_mac_header(skb); + skb->dev = cfhsi->ndev; + + /* + * We are in a callback handler and + * unfortunately we don't know what context we're + * running in. + */ + if (in_interrupt()) + netif_rx(skb); + else + netif_rx_ni(skb); + + /* Update network statistics. */ + cfhsi->ndev->stats.rx_packets++; + cfhsi->ndev->stats.rx_bytes += len; + } + + /* Calculate transfer length. */ + plen = desc->cffrm_len; + while (nfrms < CFHSI_MAX_PKTS && *plen) { + xfer_sz += *plen; + plen++; + nfrms++; + } + + /* Check for piggy-backed descriptor. */ + if (desc->header & CFHSI_PIGGY_DESC) + xfer_sz += CFHSI_DESC_SZ; + + if ((xfer_sz % 4) || (xfer_sz > (CFHSI_BUF_SZ_RX - CFHSI_DESC_SZ))) { + netdev_err(cfhsi->ndev, + "%s: Invalid payload len: %d, ignored.\n", + __func__, xfer_sz); + return -EPROTO; + } + return xfer_sz; +} + +static int cfhsi_rx_desc_len(struct cfhsi_desc *desc) +{ + int xfer_sz = 0; + int nfrms = 0; + u16 *plen; + + if ((desc->header & ~CFHSI_PIGGY_DESC) || + (desc->offset > CFHSI_MAX_EMB_FRM_SZ)) { + + pr_err("Invalid descriptor. %x %x\n", desc->header, + desc->offset); + return -EPROTO; + } + + /* Calculate transfer length. */ + plen = desc->cffrm_len; + while (nfrms < CFHSI_MAX_PKTS && *plen) { + xfer_sz += *plen; + plen++; + nfrms++; + } + + if (xfer_sz % 4) { + pr_err("Invalid payload len: %d, ignored.\n", xfer_sz); + return -EPROTO; + } + return xfer_sz; +} + +static int cfhsi_rx_pld(struct cfhsi_desc *desc, struct cfhsi *cfhsi) +{ + int rx_sz = 0; + int nfrms = 0; + u16 *plen = NULL; + u8 *pfrm = NULL; + + /* Sanity check header and offset. */ + if (WARN_ON((desc->header & ~CFHSI_PIGGY_DESC) || + (desc->offset > CFHSI_MAX_EMB_FRM_SZ))) { + netdev_err(cfhsi->ndev, "%s: Invalid descriptor.\n", + __func__); + return -EPROTO; + } + + /* Set frame pointer to start of payload. */ + pfrm = desc->emb_frm + CFHSI_MAX_EMB_FRM_SZ; + plen = desc->cffrm_len; + + /* Skip already processed frames. */ + while (nfrms < cfhsi->rx_state.nfrms) { + pfrm += *plen; + rx_sz += *plen; + plen++; + nfrms++; + } + + /* Parse payload. */ + while (nfrms < CFHSI_MAX_PKTS && *plen) { + struct sk_buff *skb; + u8 *pcffrm = NULL; + int len; + + /* CAIF frame starts after head padding. */ + pcffrm = pfrm + *pfrm + 1; + + /* Read length of CAIF frame (little endian). */ + len = *pcffrm; + len |= ((*(pcffrm + 1)) << 8) & 0xFF00; + len += 2; /* Add FCS fields. */ + + /* Sanity check length of CAIF frames. */ + if (unlikely(len > CFHSI_MAX_CAIF_FRAME_SZ)) { + netdev_err(cfhsi->ndev, "%s: Invalid length.\n", + __func__); + return -EPROTO; + } + + /* Allocate SKB (OK even in IRQ context). */ + skb = alloc_skb(len + 1, GFP_ATOMIC); + if (!skb) { + netdev_err(cfhsi->ndev, "%s: Out of memory !\n", + __func__); + cfhsi->rx_state.nfrms = nfrms; + return -ENOMEM; + } + caif_assert(skb != NULL); + + skb_put_data(skb, pcffrm, len); + + skb->protocol = htons(ETH_P_CAIF); + skb_reset_mac_header(skb); + skb->dev = cfhsi->ndev; + + /* + * We're called in callback from HSI + * and don't know the context we're running in. + */ + if (in_interrupt()) + netif_rx(skb); + else + netif_rx_ni(skb); + + /* Update network statistics. */ + cfhsi->ndev->stats.rx_packets++; + cfhsi->ndev->stats.rx_bytes += len; + + pfrm += *plen; + rx_sz += *plen; + plen++; + nfrms++; + } + + return rx_sz; +} + +static void cfhsi_rx_done(struct cfhsi *cfhsi) +{ + int res; + int desc_pld_len = 0, rx_len, rx_state; + struct cfhsi_desc *desc = NULL; + u8 *rx_ptr, *rx_buf; + struct cfhsi_desc *piggy_desc = NULL; + + desc = (struct cfhsi_desc *)cfhsi->rx_buf; + + netdev_dbg(cfhsi->ndev, "%s\n", __func__); + + if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits)) + return; + + /* Update inactivity timer if pending. */ + spin_lock_bh(&cfhsi->lock); + mod_timer_pending(&cfhsi->inactivity_timer, + jiffies + cfhsi->cfg.inactivity_timeout); + spin_unlock_bh(&cfhsi->lock); + + if (cfhsi->rx_state.state == CFHSI_RX_STATE_DESC) { + desc_pld_len = cfhsi_rx_desc_len(desc); + + if (desc_pld_len < 0) + goto out_of_sync; + + rx_buf = cfhsi->rx_buf; + rx_len = desc_pld_len; + if (desc_pld_len > 0 && (desc->header & CFHSI_PIGGY_DESC)) + rx_len += CFHSI_DESC_SZ; + if (desc_pld_len == 0) + rx_buf = cfhsi->rx_flip_buf; + } else { + rx_buf = cfhsi->rx_flip_buf; + + rx_len = CFHSI_DESC_SZ; + if (cfhsi->rx_state.pld_len > 0 && + (desc->header & CFHSI_PIGGY_DESC)) { + + piggy_desc = (struct cfhsi_desc *) + (desc->emb_frm + CFHSI_MAX_EMB_FRM_SZ + + cfhsi->rx_state.pld_len); + + cfhsi->rx_state.piggy_desc = true; + + /* Extract payload len from piggy-backed descriptor. */ + desc_pld_len = cfhsi_rx_desc_len(piggy_desc); + if (desc_pld_len < 0) + goto out_of_sync; + + if (desc_pld_len > 0) { + rx_len = desc_pld_len; + if (piggy_desc->header & CFHSI_PIGGY_DESC) + rx_len += CFHSI_DESC_SZ; + } + + /* + * Copy needed information from the piggy-backed + * descriptor to the descriptor in the start. + */ + memcpy(rx_buf, (u8 *)piggy_desc, + CFHSI_DESC_SHORT_SZ); + } + } + + if (desc_pld_len) { + rx_state = CFHSI_RX_STATE_PAYLOAD; + rx_ptr = rx_buf + CFHSI_DESC_SZ; + } else { + rx_state = CFHSI_RX_STATE_DESC; + rx_ptr = rx_buf; + rx_len = CFHSI_DESC_SZ; + } + + /* Initiate next read */ + if (test_bit(CFHSI_AWAKE, &cfhsi->bits)) { + /* Set up new transfer. */ + netdev_dbg(cfhsi->ndev, "%s: Start RX.\n", + __func__); + + res = cfhsi->ops->cfhsi_rx(rx_ptr, rx_len, + cfhsi->ops); + if (WARN_ON(res < 0)) { + netdev_err(cfhsi->ndev, "%s: RX error %d.\n", + __func__, res); + cfhsi->ndev->stats.rx_errors++; + cfhsi->ndev->stats.rx_dropped++; + } + } + + if (cfhsi->rx_state.state == CFHSI_RX_STATE_DESC) { + /* Extract payload from descriptor */ + if (cfhsi_rx_desc(desc, cfhsi) < 0) + goto out_of_sync; + } else { + /* Extract payload */ + if (cfhsi_rx_pld(desc, cfhsi) < 0) + goto out_of_sync; + if (piggy_desc) { + /* Extract any payload in piggyback descriptor. */ + if (cfhsi_rx_desc(piggy_desc, cfhsi) < 0) + goto out_of_sync; + /* Mark no embedded frame after extracting it */ + piggy_desc->offset = 0; + } + } + + /* Update state info */ + memset(&cfhsi->rx_state, 0, sizeof(cfhsi->rx_state)); + cfhsi->rx_state.state = rx_state; + cfhsi->rx_ptr = rx_ptr; + cfhsi->rx_len = rx_len; + cfhsi->rx_state.pld_len = desc_pld_len; + cfhsi->rx_state.piggy_desc = desc->header & CFHSI_PIGGY_DESC; + + if (rx_buf != cfhsi->rx_buf) + swap(cfhsi->rx_buf, cfhsi->rx_flip_buf); + return; + +out_of_sync: + netdev_err(cfhsi->ndev, "%s: Out of sync.\n", __func__); + print_hex_dump_bytes("--> ", DUMP_PREFIX_NONE, + cfhsi->rx_buf, CFHSI_DESC_SZ); + schedule_work(&cfhsi->out_of_sync_work); +} + +static void cfhsi_rx_slowpath(struct timer_list *t) +{ + struct cfhsi *cfhsi = from_timer(cfhsi, t, rx_slowpath_timer); + + netdev_dbg(cfhsi->ndev, "%s.\n", + __func__); + + cfhsi_rx_done(cfhsi); +} + +static void cfhsi_rx_done_cb(struct cfhsi_cb_ops *cb_ops) +{ + struct cfhsi *cfhsi; + + cfhsi = container_of(cb_ops, struct cfhsi, cb_ops); + netdev_dbg(cfhsi->ndev, "%s.\n", + __func__); + + if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits)) + return; + + if (test_and_clear_bit(CFHSI_FLUSH_FIFO, &cfhsi->bits)) + wake_up_interruptible(&cfhsi->flush_fifo_wait); + else + cfhsi_rx_done(cfhsi); +} + +static void cfhsi_wake_up(struct work_struct *work) +{ + struct cfhsi *cfhsi = NULL; + int res; + int len; + long ret; + + cfhsi = container_of(work, struct cfhsi, wake_up_work); + + if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits)) + return; + + if (unlikely(test_bit(CFHSI_AWAKE, &cfhsi->bits))) { + /* It happenes when wakeup is requested by + * both ends at the same time. */ + clear_bit(CFHSI_WAKE_UP, &cfhsi->bits); + clear_bit(CFHSI_WAKE_UP_ACK, &cfhsi->bits); + return; + } + + /* Activate wake line. */ + cfhsi->ops->cfhsi_wake_up(cfhsi->ops); + + netdev_dbg(cfhsi->ndev, "%s: Start waiting.\n", + __func__); + + /* Wait for acknowledge. */ + ret = CFHSI_WAKE_TOUT; + ret = wait_event_interruptible_timeout(cfhsi->wake_up_wait, + test_and_clear_bit(CFHSI_WAKE_UP_ACK, + &cfhsi->bits), ret); + if (unlikely(ret < 0)) { + /* Interrupted by signal. */ + netdev_err(cfhsi->ndev, "%s: Signalled: %ld.\n", + __func__, ret); + + clear_bit(CFHSI_WAKE_UP, &cfhsi->bits); + cfhsi->ops->cfhsi_wake_down(cfhsi->ops); + return; + } else if (!ret) { + bool ca_wake = false; + size_t fifo_occupancy = 0; + + /* Wakeup timeout */ + netdev_dbg(cfhsi->ndev, "%s: Timeout.\n", + __func__); + + /* Check FIFO to check if modem has sent something. */ + WARN_ON(cfhsi->ops->cfhsi_fifo_occupancy(cfhsi->ops, + &fifo_occupancy)); + + netdev_dbg(cfhsi->ndev, "%s: Bytes in FIFO: %u.\n", + __func__, (unsigned) fifo_occupancy); + + /* Check if we misssed the interrupt. */ + WARN_ON(cfhsi->ops->cfhsi_get_peer_wake(cfhsi->ops, + &ca_wake)); + + if (ca_wake) { + netdev_err(cfhsi->ndev, "%s: CA Wake missed !.\n", + __func__); + + /* Clear the CFHSI_WAKE_UP_ACK bit to prevent race. */ + clear_bit(CFHSI_WAKE_UP_ACK, &cfhsi->bits); + + /* Continue execution. */ + goto wake_ack; + } + + clear_bit(CFHSI_WAKE_UP, &cfhsi->bits); + cfhsi->ops->cfhsi_wake_down(cfhsi->ops); + return; + } +wake_ack: + netdev_dbg(cfhsi->ndev, "%s: Woken.\n", + __func__); + + /* Clear power up bit. */ + set_bit(CFHSI_AWAKE, &cfhsi->bits); + clear_bit(CFHSI_WAKE_UP, &cfhsi->bits); + + /* Resume read operation. */ + netdev_dbg(cfhsi->ndev, "%s: Start RX.\n", __func__); + res = cfhsi->ops->cfhsi_rx(cfhsi->rx_ptr, cfhsi->rx_len, cfhsi->ops); + + if (WARN_ON(res < 0)) + netdev_err(cfhsi->ndev, "%s: RX err %d.\n", __func__, res); + + /* Clear power up acknowledment. */ + clear_bit(CFHSI_WAKE_UP_ACK, &cfhsi->bits); + + spin_lock_bh(&cfhsi->lock); + + /* Resume transmit if queues are not empty. */ + if (!cfhsi_tx_queue_len(cfhsi)) { + netdev_dbg(cfhsi->ndev, "%s: Peer wake, start timer.\n", + __func__); + /* Start inactivity timer. */ + mod_timer(&cfhsi->inactivity_timer, + jiffies + cfhsi->cfg.inactivity_timeout); + spin_unlock_bh(&cfhsi->lock); + return; + } + + netdev_dbg(cfhsi->ndev, "%s: Host wake.\n", + __func__); + + spin_unlock_bh(&cfhsi->lock); + + /* Create HSI frame. */ + len = cfhsi_tx_frm((struct cfhsi_desc *)cfhsi->tx_buf, cfhsi); + + if (likely(len > 0)) { + /* Set up new transfer. */ + res = cfhsi->ops->cfhsi_tx(cfhsi->tx_buf, len, cfhsi->ops); + if (WARN_ON(res < 0)) { + netdev_err(cfhsi->ndev, "%s: TX error %d.\n", + __func__, res); + cfhsi_abort_tx(cfhsi); + } + } else { + netdev_err(cfhsi->ndev, + "%s: Failed to create HSI frame: %d.\n", + __func__, len); + } +} + +static void cfhsi_wake_down(struct work_struct *work) +{ + long ret; + struct cfhsi *cfhsi = NULL; + size_t fifo_occupancy = 0; + int retry = CFHSI_WAKE_TOUT; + + cfhsi = container_of(work, struct cfhsi, wake_down_work); + netdev_dbg(cfhsi->ndev, "%s.\n", __func__); + + if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits)) + return; + + /* Deactivate wake line. */ + cfhsi->ops->cfhsi_wake_down(cfhsi->ops); + + /* Wait for acknowledge. */ + ret = CFHSI_WAKE_TOUT; + ret = wait_event_interruptible_timeout(cfhsi->wake_down_wait, + test_and_clear_bit(CFHSI_WAKE_DOWN_ACK, + &cfhsi->bits), ret); + if (ret < 0) { + /* Interrupted by signal. */ + netdev_err(cfhsi->ndev, "%s: Signalled: %ld.\n", + __func__, ret); + return; + } else if (!ret) { + bool ca_wake = true; + + /* Timeout */ + netdev_err(cfhsi->ndev, "%s: Timeout.\n", __func__); + + /* Check if we misssed the interrupt. */ + WARN_ON(cfhsi->ops->cfhsi_get_peer_wake(cfhsi->ops, + &ca_wake)); + if (!ca_wake) + netdev_err(cfhsi->ndev, "%s: CA Wake missed !.\n", + __func__); + } + + /* Check FIFO occupancy. */ + while (retry) { + WARN_ON(cfhsi->ops->cfhsi_fifo_occupancy(cfhsi->ops, + &fifo_occupancy)); + + if (!fifo_occupancy) + break; + + set_current_state(TASK_INTERRUPTIBLE); + schedule_timeout(1); + retry--; + } + + if (!retry) + netdev_err(cfhsi->ndev, "%s: FIFO Timeout.\n", __func__); + + /* Clear AWAKE condition. */ + clear_bit(CFHSI_AWAKE, &cfhsi->bits); + + /* Cancel pending RX requests. */ + cfhsi->ops->cfhsi_rx_cancel(cfhsi->ops); +} + +static void cfhsi_out_of_sync(struct work_struct *work) +{ + struct cfhsi *cfhsi = NULL; + + cfhsi = container_of(work, struct cfhsi, out_of_sync_work); + + rtnl_lock(); + dev_close(cfhsi->ndev); + rtnl_unlock(); +} + +static void cfhsi_wake_up_cb(struct cfhsi_cb_ops *cb_ops) +{ + struct cfhsi *cfhsi = NULL; + + cfhsi = container_of(cb_ops, struct cfhsi, cb_ops); + netdev_dbg(cfhsi->ndev, "%s.\n", + __func__); + + set_bit(CFHSI_WAKE_UP_ACK, &cfhsi->bits); + wake_up_interruptible(&cfhsi->wake_up_wait); + + if (test_bit(CFHSI_SHUTDOWN, &cfhsi->bits)) + return; + + /* Schedule wake up work queue if the peer initiates. */ + if (!test_and_set_bit(CFHSI_WAKE_UP, &cfhsi->bits)) + queue_work(cfhsi->wq, &cfhsi->wake_up_work); +} + +static void cfhsi_wake_down_cb(struct cfhsi_cb_ops *cb_ops) +{ + struct cfhsi *cfhsi = NULL; + + cfhsi = container_of(cb_ops, struct cfhsi, cb_ops); + netdev_dbg(cfhsi->ndev, "%s.\n", + __func__); + + /* Initiating low power is only permitted by the host (us). */ + set_bit(CFHSI_WAKE_DOWN_ACK, &cfhsi->bits); + wake_up_interruptible(&cfhsi->wake_down_wait); +} + +static void cfhsi_aggregation_tout(struct timer_list *t) +{ + struct cfhsi *cfhsi = from_timer(cfhsi, t, aggregation_timer); + + netdev_dbg(cfhsi->ndev, "%s.\n", + __func__); + + cfhsi_start_tx(cfhsi); +} + +static int cfhsi_xmit(struct sk_buff *skb, struct net_device *dev) +{ + struct cfhsi *cfhsi = NULL; + int start_xfer = 0; + int timer_active; + int prio; + + if (!dev) + return -EINVAL; + + cfhsi = netdev_priv(dev); + + switch (skb->priority) { + case TC_PRIO_BESTEFFORT: + case TC_PRIO_FILLER: + case TC_PRIO_BULK: + prio = CFHSI_PRIO_BEBK; + break; + case TC_PRIO_INTERACTIVE_BULK: + prio = CFHSI_PRIO_VI; + break; + case TC_PRIO_INTERACTIVE: + prio = CFHSI_PRIO_VO; + break; + case TC_PRIO_CONTROL: + default: + prio = CFHSI_PRIO_CTL; + break; + } + + spin_lock_bh(&cfhsi->lock); + + /* Update aggregation statistics */ + cfhsi_update_aggregation_stats(cfhsi, skb, 1); + + /* Queue the SKB */ + skb_queue_tail(&cfhsi->qhead[prio], skb); + + /* Sanity check; xmit should not be called after unregister_netdev */ + if (WARN_ON(test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))) { + spin_unlock_bh(&cfhsi->lock); + cfhsi_abort_tx(cfhsi); + return -EINVAL; + } + + /* Send flow off if number of packets is above high water mark. */ + if (!cfhsi->flow_off_sent && + cfhsi_tx_queue_len(cfhsi) > cfhsi->cfg.q_high_mark && + cfhsi->cfdev.flowctrl) { + cfhsi->flow_off_sent = 1; + cfhsi->cfdev.flowctrl(cfhsi->ndev, OFF); + } + + if (cfhsi->tx_state == CFHSI_TX_STATE_IDLE) { + cfhsi->tx_state = CFHSI_TX_STATE_XFER; + start_xfer = 1; + } + + if (!start_xfer) { + /* Send aggregate if it is possible */ + bool aggregate_ready = + cfhsi_can_send_aggregate(cfhsi) && + del_timer(&cfhsi->aggregation_timer) > 0; + spin_unlock_bh(&cfhsi->lock); + if (aggregate_ready) + cfhsi_start_tx(cfhsi); + return 0; + } + + /* Delete inactivity timer if started. */ + timer_active = del_timer_sync(&cfhsi->inactivity_timer); + + spin_unlock_bh(&cfhsi->lock); + + if (timer_active) { + struct cfhsi_desc *desc = (struct cfhsi_desc *)cfhsi->tx_buf; + int len; + int res; + + /* Create HSI frame. */ + len = cfhsi_tx_frm(desc, cfhsi); + WARN_ON(!len); + + /* Set up new transfer. */ + res = cfhsi->ops->cfhsi_tx(cfhsi->tx_buf, len, cfhsi->ops); + if (WARN_ON(res < 0)) { + netdev_err(cfhsi->ndev, "%s: TX error %d.\n", + __func__, res); + cfhsi_abort_tx(cfhsi); + } + } else { + /* Schedule wake up work queue if the we initiate. */ + if (!test_and_set_bit(CFHSI_WAKE_UP, &cfhsi->bits)) + queue_work(cfhsi->wq, &cfhsi->wake_up_work); + } + + return 0; +} + +static const struct net_device_ops cfhsi_netdevops; + +static void cfhsi_setup(struct net_device *dev) +{ + int i; + struct cfhsi *cfhsi = netdev_priv(dev); + dev->features = 0; + dev->type = ARPHRD_CAIF; + dev->flags = IFF_POINTOPOINT | IFF_NOARP; + dev->mtu = CFHSI_MAX_CAIF_FRAME_SZ; + dev->priv_flags |= IFF_NO_QUEUE; + dev->needs_free_netdev = true; + dev->netdev_ops = &cfhsi_netdevops; + for (i = 0; i < CFHSI_PRIO_LAST; ++i) + skb_queue_head_init(&cfhsi->qhead[i]); + cfhsi->cfdev.link_select = CAIF_LINK_HIGH_BANDW; + cfhsi->cfdev.use_frag = false; + cfhsi->cfdev.use_stx = false; + cfhsi->cfdev.use_fcs = false; + cfhsi->ndev = dev; + cfhsi->cfg = hsi_default_config; +} + +static int cfhsi_open(struct net_device *ndev) +{ + struct cfhsi *cfhsi = netdev_priv(ndev); + int res; + + clear_bit(CFHSI_SHUTDOWN, &cfhsi->bits); + + /* Initialize state vaiables. */ + cfhsi->tx_state = CFHSI_TX_STATE_IDLE; + cfhsi->rx_state.state = CFHSI_RX_STATE_DESC; + + /* Set flow info */ + cfhsi->flow_off_sent = 0; + + /* + * Allocate a TX buffer with the size of a HSI packet descriptors + * and the necessary room for CAIF payload frames. + */ + cfhsi->tx_buf = kzalloc(CFHSI_BUF_SZ_TX, GFP_KERNEL); + if (!cfhsi->tx_buf) { + res = -ENODEV; + goto err_alloc_tx; + } + + /* + * Allocate a RX buffer with the size of two HSI packet descriptors and + * the necessary room for CAIF payload frames. + */ + cfhsi->rx_buf = kzalloc(CFHSI_BUF_SZ_RX, GFP_KERNEL); + if (!cfhsi->rx_buf) { + res = -ENODEV; + goto err_alloc_rx; + } + + cfhsi->rx_flip_buf = kzalloc(CFHSI_BUF_SZ_RX, GFP_KERNEL); + if (!cfhsi->rx_flip_buf) { + res = -ENODEV; + goto err_alloc_rx_flip; + } + + /* Initialize aggregation timeout */ + cfhsi->cfg.aggregation_timeout = hsi_default_config.aggregation_timeout; + + /* Initialize recieve vaiables. */ + cfhsi->rx_ptr = cfhsi->rx_buf; + cfhsi->rx_len = CFHSI_DESC_SZ; + + /* Initialize spin locks. */ + spin_lock_init(&cfhsi->lock); + + /* Set up the driver. */ + cfhsi->cb_ops.tx_done_cb = cfhsi_tx_done_cb; + cfhsi->cb_ops.rx_done_cb = cfhsi_rx_done_cb; + cfhsi->cb_ops.wake_up_cb = cfhsi_wake_up_cb; + cfhsi->cb_ops.wake_down_cb = cfhsi_wake_down_cb; + + /* Initialize the work queues. */ + INIT_WORK(&cfhsi->wake_up_work, cfhsi_wake_up); + INIT_WORK(&cfhsi->wake_down_work, cfhsi_wake_down); + INIT_WORK(&cfhsi->out_of_sync_work, cfhsi_out_of_sync); + + /* Clear all bit fields. */ + clear_bit(CFHSI_WAKE_UP_ACK, &cfhsi->bits); + clear_bit(CFHSI_WAKE_DOWN_ACK, &cfhsi->bits); + clear_bit(CFHSI_WAKE_UP, &cfhsi->bits); + clear_bit(CFHSI_AWAKE, &cfhsi->bits); + + /* Create work thread. */ + cfhsi->wq = alloc_ordered_workqueue(cfhsi->ndev->name, WQ_MEM_RECLAIM); + if (!cfhsi->wq) { + netdev_err(cfhsi->ndev, "%s: Failed to create work queue.\n", + __func__); + res = -ENODEV; + goto err_create_wq; + } + + /* Initialize wait queues. */ + init_waitqueue_head(&cfhsi->wake_up_wait); + init_waitqueue_head(&cfhsi->wake_down_wait); + init_waitqueue_head(&cfhsi->flush_fifo_wait); + + /* Setup the inactivity timer. */ + timer_setup(&cfhsi->inactivity_timer, cfhsi_inactivity_tout, 0); + /* Setup the slowpath RX timer. */ + timer_setup(&cfhsi->rx_slowpath_timer, cfhsi_rx_slowpath, 0); + /* Setup the aggregation timer. */ + timer_setup(&cfhsi->aggregation_timer, cfhsi_aggregation_tout, 0); + + /* Activate HSI interface. */ + res = cfhsi->ops->cfhsi_up(cfhsi->ops); + if (res) { + netdev_err(cfhsi->ndev, + "%s: can't activate HSI interface: %d.\n", + __func__, res); + goto err_activate; + } + + /* Flush FIFO */ + res = cfhsi_flush_fifo(cfhsi); + if (res) { + netdev_err(cfhsi->ndev, "%s: Can't flush FIFO: %d.\n", + __func__, res); + goto err_net_reg; + } + return res; + + err_net_reg: + cfhsi->ops->cfhsi_down(cfhsi->ops); + err_activate: + destroy_workqueue(cfhsi->wq); + err_create_wq: + kfree(cfhsi->rx_flip_buf); + err_alloc_rx_flip: + kfree(cfhsi->rx_buf); + err_alloc_rx: + kfree(cfhsi->tx_buf); + err_alloc_tx: + return res; +} + +static int cfhsi_close(struct net_device *ndev) +{ + struct cfhsi *cfhsi = netdev_priv(ndev); + u8 *tx_buf, *rx_buf, *flip_buf; + + /* going to shutdown driver */ + set_bit(CFHSI_SHUTDOWN, &cfhsi->bits); + + /* Delete timers if pending */ + del_timer_sync(&cfhsi->inactivity_timer); + del_timer_sync(&cfhsi->rx_slowpath_timer); + del_timer_sync(&cfhsi->aggregation_timer); + + /* Cancel pending RX request (if any) */ + cfhsi->ops->cfhsi_rx_cancel(cfhsi->ops); + + /* Destroy workqueue */ + destroy_workqueue(cfhsi->wq); + + /* Store bufferes: will be freed later. */ + tx_buf = cfhsi->tx_buf; + rx_buf = cfhsi->rx_buf; + flip_buf = cfhsi->rx_flip_buf; + /* Flush transmit queues. */ + cfhsi_abort_tx(cfhsi); + + /* Deactivate interface */ + cfhsi->ops->cfhsi_down(cfhsi->ops); + + /* Free buffers. */ + kfree(tx_buf); + kfree(rx_buf); + kfree(flip_buf); + return 0; +} + +static void cfhsi_uninit(struct net_device *dev) +{ + struct cfhsi *cfhsi = netdev_priv(dev); + ASSERT_RTNL(); + symbol_put(cfhsi_get_device); + list_del(&cfhsi->list); +} + +static const struct net_device_ops cfhsi_netdevops = { + .ndo_uninit = cfhsi_uninit, + .ndo_open = cfhsi_open, + .ndo_stop = cfhsi_close, + .ndo_start_xmit = cfhsi_xmit +}; + +static void cfhsi_netlink_parms(struct nlattr *data[], struct cfhsi *cfhsi) +{ + int i; + + if (!data) { + pr_debug("no params data found\n"); + return; + } + + i = __IFLA_CAIF_HSI_INACTIVITY_TOUT; + /* + * Inactivity timeout in millisecs. Lowest possible value is 1, + * and highest possible is NEXT_TIMER_MAX_DELTA. + */ + if (data[i]) { + u32 inactivity_timeout = nla_get_u32(data[i]); + /* Pre-calculate inactivity timeout. */ + cfhsi->cfg.inactivity_timeout = inactivity_timeout * HZ / 1000; + if (cfhsi->cfg.inactivity_timeout == 0) + cfhsi->cfg.inactivity_timeout = 1; + else if (cfhsi->cfg.inactivity_timeout > NEXT_TIMER_MAX_DELTA) + cfhsi->cfg.inactivity_timeout = NEXT_TIMER_MAX_DELTA; + } + + i = __IFLA_CAIF_HSI_AGGREGATION_TOUT; + if (data[i]) + cfhsi->cfg.aggregation_timeout = nla_get_u32(data[i]); + + i = __IFLA_CAIF_HSI_HEAD_ALIGN; + if (data[i]) + cfhsi->cfg.head_align = nla_get_u32(data[i]); + + i = __IFLA_CAIF_HSI_TAIL_ALIGN; + if (data[i]) + cfhsi->cfg.tail_align = nla_get_u32(data[i]); + + i = __IFLA_CAIF_HSI_QHIGH_WATERMARK; + if (data[i]) + cfhsi->cfg.q_high_mark = nla_get_u32(data[i]); + + i = __IFLA_CAIF_HSI_QLOW_WATERMARK; + if (data[i]) + cfhsi->cfg.q_low_mark = nla_get_u32(data[i]); +} + +static int caif_hsi_changelink(struct net_device *dev, struct nlattr *tb[], + struct nlattr *data[], + struct netlink_ext_ack *extack) +{ + cfhsi_netlink_parms(data, netdev_priv(dev)); + netdev_state_change(dev); + return 0; +} + +static const struct nla_policy caif_hsi_policy[__IFLA_CAIF_HSI_MAX + 1] = { + [__IFLA_CAIF_HSI_INACTIVITY_TOUT] = { .type = NLA_U32, .len = 4 }, + [__IFLA_CAIF_HSI_AGGREGATION_TOUT] = { .type = NLA_U32, .len = 4 }, + [__IFLA_CAIF_HSI_HEAD_ALIGN] = { .type = NLA_U32, .len = 4 }, + [__IFLA_CAIF_HSI_TAIL_ALIGN] = { .type = NLA_U32, .len = 4 }, + [__IFLA_CAIF_HSI_QHIGH_WATERMARK] = { .type = NLA_U32, .len = 4 }, + [__IFLA_CAIF_HSI_QLOW_WATERMARK] = { .type = NLA_U32, .len = 4 }, +}; + +static size_t caif_hsi_get_size(const struct net_device *dev) +{ + int i; + size_t s = 0; + for (i = __IFLA_CAIF_HSI_UNSPEC + 1; i < __IFLA_CAIF_HSI_MAX; i++) + s += nla_total_size(caif_hsi_policy[i].len); + return s; +} + +static int caif_hsi_fill_info(struct sk_buff *skb, const struct net_device *dev) +{ + struct cfhsi *cfhsi = netdev_priv(dev); + + if (nla_put_u32(skb, __IFLA_CAIF_HSI_INACTIVITY_TOUT, + cfhsi->cfg.inactivity_timeout) || + nla_put_u32(skb, __IFLA_CAIF_HSI_AGGREGATION_TOUT, + cfhsi->cfg.aggregation_timeout) || + nla_put_u32(skb, __IFLA_CAIF_HSI_HEAD_ALIGN, + cfhsi->cfg.head_align) || + nla_put_u32(skb, __IFLA_CAIF_HSI_TAIL_ALIGN, + cfhsi->cfg.tail_align) || + nla_put_u32(skb, __IFLA_CAIF_HSI_QHIGH_WATERMARK, + cfhsi->cfg.q_high_mark) || + nla_put_u32(skb, __IFLA_CAIF_HSI_QLOW_WATERMARK, + cfhsi->cfg.q_low_mark)) + return -EMSGSIZE; + + return 0; +} + +static int caif_hsi_newlink(struct net *src_net, struct net_device *dev, + struct nlattr *tb[], struct nlattr *data[], + struct netlink_ext_ack *extack) +{ + struct cfhsi *cfhsi = NULL; + struct cfhsi_ops *(*get_ops)(void); + + ASSERT_RTNL(); + + cfhsi = netdev_priv(dev); + cfhsi_netlink_parms(data, cfhsi); + + get_ops = symbol_get(cfhsi_get_ops); + if (!get_ops) { + pr_err("%s: failed to get the cfhsi_ops\n", __func__); + return -ENODEV; + } + + /* Assign the HSI device. */ + cfhsi->ops = (*get_ops)(); + if (!cfhsi->ops) { + pr_err("%s: failed to get the cfhsi_ops\n", __func__); + goto err; + } + + /* Assign the driver to this HSI device. */ + cfhsi->ops->cb_ops = &cfhsi->cb_ops; + if (register_netdevice(dev)) { + pr_warn("%s: caif_hsi device registration failed\n", __func__); + goto err; + } + /* Add CAIF HSI device to list. */ + list_add_tail(&cfhsi->list, &cfhsi_list); + + return 0; +err: + symbol_put(cfhsi_get_ops); + return -ENODEV; +} + +static struct rtnl_link_ops caif_hsi_link_ops __read_mostly = { + .kind = "cfhsi", + .priv_size = sizeof(struct cfhsi), + .setup = cfhsi_setup, + .maxtype = __IFLA_CAIF_HSI_MAX, + .policy = caif_hsi_policy, + .newlink = caif_hsi_newlink, + .changelink = caif_hsi_changelink, + .get_size = caif_hsi_get_size, + .fill_info = caif_hsi_fill_info, +}; + +static void __exit cfhsi_exit_module(void) +{ + struct list_head *list_node; + struct list_head *n; + struct cfhsi *cfhsi; + + rtnl_link_unregister(&caif_hsi_link_ops); + + rtnl_lock(); + list_for_each_safe(list_node, n, &cfhsi_list) { + cfhsi = list_entry(list_node, struct cfhsi, list); + unregister_netdevice(cfhsi->ndev); + } + rtnl_unlock(); +} + +static int __init cfhsi_init_module(void) +{ + return rtnl_link_register(&caif_hsi_link_ops); +} + +module_init(cfhsi_init_module); +module_exit(cfhsi_exit_module); diff --git a/drivers/net/caif/caif_serial.c b/drivers/net/caif/caif_serial.c new file mode 100644 index 000000000..81ec17b9c --- /dev/null +++ b/drivers/net/caif/caif_serial.c @@ -0,0 +1,472 @@ +/* + * Copyright (C) ST-Ericsson AB 2010 + * Author: Sjur Brendeland + * License terms: GNU General Public License (GPL) version 2 + */ + +#include <linux/hardirq.h> +#include <linux/init.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/types.h> +#include <linux/skbuff.h> +#include <linux/netdevice.h> +#include <linux/rtnetlink.h> +#include <linux/tty.h> +#include <linux/file.h> +#include <linux/if_arp.h> +#include <net/caif/caif_device.h> +#include <net/caif/cfcnfg.h> +#include <linux/err.h> +#include <linux/debugfs.h> + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Sjur Brendeland"); +MODULE_DESCRIPTION("CAIF serial device TTY line discipline"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_LDISC(N_CAIF); + +#define SEND_QUEUE_LOW 10 +#define SEND_QUEUE_HIGH 100 +#define CAIF_SENDING 1 /* Bit 1 = 0x02*/ +#define CAIF_FLOW_OFF_SENT 4 /* Bit 4 = 0x10 */ +#define MAX_WRITE_CHUNK 4096 +#define ON 1 +#define OFF 0 +#define CAIF_MAX_MTU 4096 + +static DEFINE_SPINLOCK(ser_lock); +static LIST_HEAD(ser_list); +static LIST_HEAD(ser_release_list); + +static bool ser_loop; +module_param(ser_loop, bool, 0444); +MODULE_PARM_DESC(ser_loop, "Run in simulated loopback mode."); + +static bool ser_use_stx = true; +module_param(ser_use_stx, bool, 0444); +MODULE_PARM_DESC(ser_use_stx, "STX enabled or not."); + +static bool ser_use_fcs = true; + +module_param(ser_use_fcs, bool, 0444); +MODULE_PARM_DESC(ser_use_fcs, "FCS enabled or not."); + +static int ser_write_chunk = MAX_WRITE_CHUNK; +module_param(ser_write_chunk, int, 0444); + +MODULE_PARM_DESC(ser_write_chunk, "Maximum size of data written to UART."); + +static struct dentry *debugfsdir; + +static int caif_net_open(struct net_device *dev); +static int caif_net_close(struct net_device *dev); + +struct ser_device { + struct caif_dev_common common; + struct list_head node; + struct net_device *dev; + struct sk_buff_head head; + struct tty_struct *tty; + bool tx_started; + unsigned long state; +#ifdef CONFIG_DEBUG_FS + struct dentry *debugfs_tty_dir; + struct debugfs_blob_wrapper tx_blob; + struct debugfs_blob_wrapper rx_blob; + u8 rx_data[128]; + u8 tx_data[128]; + u8 tty_status; + +#endif +}; + +static void caifdev_setup(struct net_device *dev); +static void ldisc_tx_wakeup(struct tty_struct *tty); +#ifdef CONFIG_DEBUG_FS +static inline void update_tty_status(struct ser_device *ser) +{ + ser->tty_status = + ser->tty->stopped << 5 | + ser->tty->flow_stopped << 3 | + ser->tty->packet << 2 | + ser->tty->port->low_latency << 1; +} +static inline void debugfs_init(struct ser_device *ser, struct tty_struct *tty) +{ + ser->debugfs_tty_dir = + debugfs_create_dir(tty->name, debugfsdir); + if (!IS_ERR(ser->debugfs_tty_dir)) { + debugfs_create_blob("last_tx_msg", 0400, + ser->debugfs_tty_dir, + &ser->tx_blob); + + debugfs_create_blob("last_rx_msg", 0400, + ser->debugfs_tty_dir, + &ser->rx_blob); + + debugfs_create_x32("ser_state", 0400, + ser->debugfs_tty_dir, + (u32 *)&ser->state); + + debugfs_create_x8("tty_status", 0400, + ser->debugfs_tty_dir, + &ser->tty_status); + + } + ser->tx_blob.data = ser->tx_data; + ser->tx_blob.size = 0; + ser->rx_blob.data = ser->rx_data; + ser->rx_blob.size = 0; +} + +static inline void debugfs_deinit(struct ser_device *ser) +{ + debugfs_remove_recursive(ser->debugfs_tty_dir); +} + +static inline void debugfs_rx(struct ser_device *ser, const u8 *data, int size) +{ + if (size > sizeof(ser->rx_data)) + size = sizeof(ser->rx_data); + memcpy(ser->rx_data, data, size); + ser->rx_blob.data = ser->rx_data; + ser->rx_blob.size = size; +} + +static inline void debugfs_tx(struct ser_device *ser, const u8 *data, int size) +{ + if (size > sizeof(ser->tx_data)) + size = sizeof(ser->tx_data); + memcpy(ser->tx_data, data, size); + ser->tx_blob.data = ser->tx_data; + ser->tx_blob.size = size; +} +#else +static inline void debugfs_init(struct ser_device *ser, struct tty_struct *tty) +{ +} + +static inline void debugfs_deinit(struct ser_device *ser) +{ +} + +static inline void update_tty_status(struct ser_device *ser) +{ +} + +static inline void debugfs_rx(struct ser_device *ser, const u8 *data, int size) +{ +} + +static inline void debugfs_tx(struct ser_device *ser, const u8 *data, int size) +{ +} + +#endif + +static void ldisc_receive(struct tty_struct *tty, const u8 *data, + char *flags, int count) +{ + struct sk_buff *skb = NULL; + struct ser_device *ser; + int ret; + + ser = tty->disc_data; + + /* + * NOTE: flags may contain information about break or overrun. + * This is not yet handled. + */ + + + /* + * Workaround for garbage at start of transmission, + * only enable if STX handling is not enabled. + */ + if (!ser->common.use_stx && !ser->tx_started) { + dev_info(&ser->dev->dev, + "Bytes received before initial transmission -" + "bytes discarded.\n"); + return; + } + + BUG_ON(ser->dev == NULL); + + /* Get a suitable caif packet and copy in data. */ + skb = netdev_alloc_skb(ser->dev, count+1); + if (skb == NULL) + return; + skb_put_data(skb, data, count); + + skb->protocol = htons(ETH_P_CAIF); + skb_reset_mac_header(skb); + debugfs_rx(ser, data, count); + /* Push received packet up the stack. */ + ret = netif_rx_ni(skb); + if (!ret) { + ser->dev->stats.rx_packets++; + ser->dev->stats.rx_bytes += count; + } else + ++ser->dev->stats.rx_dropped; + update_tty_status(ser); +} + +static int handle_tx(struct ser_device *ser) +{ + struct tty_struct *tty; + struct sk_buff *skb; + int tty_wr, len, room; + + tty = ser->tty; + ser->tx_started = true; + + /* Enter critical section */ + if (test_and_set_bit(CAIF_SENDING, &ser->state)) + return 0; + + /* skb_peek is safe because handle_tx is called after skb_queue_tail */ + while ((skb = skb_peek(&ser->head)) != NULL) { + + /* Make sure you don't write too much */ + len = skb->len; + room = tty_write_room(tty); + if (!room) + break; + if (room > ser_write_chunk) + room = ser_write_chunk; + if (len > room) + len = room; + + /* Write to tty or loopback */ + if (!ser_loop) { + tty_wr = tty->ops->write(tty, skb->data, len); + update_tty_status(ser); + } else { + tty_wr = len; + ldisc_receive(tty, skb->data, NULL, len); + } + ser->dev->stats.tx_packets++; + ser->dev->stats.tx_bytes += tty_wr; + + /* Error on TTY ?! */ + if (tty_wr < 0) + goto error; + /* Reduce buffer written, and discard if empty */ + skb_pull(skb, tty_wr); + if (skb->len == 0) { + struct sk_buff *tmp = skb_dequeue(&ser->head); + WARN_ON(tmp != skb); + if (in_interrupt()) + dev_kfree_skb_irq(skb); + else + kfree_skb(skb); + } + } + /* Send flow off if queue is empty */ + if (ser->head.qlen <= SEND_QUEUE_LOW && + test_and_clear_bit(CAIF_FLOW_OFF_SENT, &ser->state) && + ser->common.flowctrl != NULL) + ser->common.flowctrl(ser->dev, ON); + clear_bit(CAIF_SENDING, &ser->state); + return 0; +error: + clear_bit(CAIF_SENDING, &ser->state); + return tty_wr; +} + +static int caif_xmit(struct sk_buff *skb, struct net_device *dev) +{ + struct ser_device *ser; + + ser = netdev_priv(dev); + + /* Send flow off once, on high water mark */ + if (ser->head.qlen > SEND_QUEUE_HIGH && + !test_and_set_bit(CAIF_FLOW_OFF_SENT, &ser->state) && + ser->common.flowctrl != NULL) + + ser->common.flowctrl(ser->dev, OFF); + + skb_queue_tail(&ser->head, skb); + return handle_tx(ser); +} + + +static void ldisc_tx_wakeup(struct tty_struct *tty) +{ + struct ser_device *ser; + + ser = tty->disc_data; + BUG_ON(ser == NULL); + WARN_ON(ser->tty != tty); + handle_tx(ser); +} + + +static void ser_release(struct work_struct *work) +{ + struct list_head list; + struct ser_device *ser, *tmp; + + spin_lock(&ser_lock); + list_replace_init(&ser_release_list, &list); + spin_unlock(&ser_lock); + + if (!list_empty(&list)) { + rtnl_lock(); + list_for_each_entry_safe(ser, tmp, &list, node) { + dev_close(ser->dev); + unregister_netdevice(ser->dev); + debugfs_deinit(ser); + } + rtnl_unlock(); + } +} + +static DECLARE_WORK(ser_release_work, ser_release); + +static int ldisc_open(struct tty_struct *tty) +{ + struct ser_device *ser; + struct net_device *dev; + char name[64]; + int result; + + /* No write no play */ + if (tty->ops->write == NULL) + return -EOPNOTSUPP; + if (!capable(CAP_SYS_ADMIN) && !capable(CAP_SYS_TTY_CONFIG)) + return -EPERM; + + /* release devices to avoid name collision */ + ser_release(NULL); + + result = snprintf(name, sizeof(name), "cf%s", tty->name); + if (result >= IFNAMSIZ) + return -EINVAL; + dev = alloc_netdev(sizeof(*ser), name, NET_NAME_UNKNOWN, + caifdev_setup); + if (!dev) + return -ENOMEM; + + ser = netdev_priv(dev); + ser->tty = tty_kref_get(tty); + ser->dev = dev; + debugfs_init(ser, tty); + tty->receive_room = N_TTY_BUF_SIZE; + tty->disc_data = ser; + set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags); + rtnl_lock(); + result = register_netdevice(dev); + if (result) { + tty_kref_put(tty); + rtnl_unlock(); + free_netdev(dev); + return -ENODEV; + } + + spin_lock(&ser_lock); + list_add(&ser->node, &ser_list); + spin_unlock(&ser_lock); + rtnl_unlock(); + netif_stop_queue(dev); + update_tty_status(ser); + return 0; +} + +static void ldisc_close(struct tty_struct *tty) +{ + struct ser_device *ser = tty->disc_data; + + tty_kref_put(ser->tty); + + spin_lock(&ser_lock); + list_move(&ser->node, &ser_release_list); + spin_unlock(&ser_lock); + schedule_work(&ser_release_work); +} + +/* The line discipline structure. */ +static struct tty_ldisc_ops caif_ldisc = { + .owner = THIS_MODULE, + .magic = TTY_LDISC_MAGIC, + .name = "n_caif", + .open = ldisc_open, + .close = ldisc_close, + .receive_buf = ldisc_receive, + .write_wakeup = ldisc_tx_wakeup +}; + +static int register_ldisc(void) +{ + int result; + + result = tty_register_ldisc(N_CAIF, &caif_ldisc); + if (result < 0) { + pr_err("cannot register CAIF ldisc=%d err=%d\n", N_CAIF, + result); + return result; + } + return result; +} +static const struct net_device_ops netdev_ops = { + .ndo_open = caif_net_open, + .ndo_stop = caif_net_close, + .ndo_start_xmit = caif_xmit +}; + +static void caifdev_setup(struct net_device *dev) +{ + struct ser_device *serdev = netdev_priv(dev); + + dev->features = 0; + dev->netdev_ops = &netdev_ops; + dev->type = ARPHRD_CAIF; + dev->flags = IFF_POINTOPOINT | IFF_NOARP; + dev->mtu = CAIF_MAX_MTU; + dev->priv_flags |= IFF_NO_QUEUE; + dev->needs_free_netdev = true; + skb_queue_head_init(&serdev->head); + serdev->common.link_select = CAIF_LINK_LOW_LATENCY; + serdev->common.use_frag = true; + serdev->common.use_stx = ser_use_stx; + serdev->common.use_fcs = ser_use_fcs; + serdev->dev = dev; +} + + +static int caif_net_open(struct net_device *dev) +{ + netif_wake_queue(dev); + return 0; +} + +static int caif_net_close(struct net_device *dev) +{ + netif_stop_queue(dev); + return 0; +} + +static int __init caif_ser_init(void) +{ + int ret; + + ret = register_ldisc(); + debugfsdir = debugfs_create_dir("caif_serial", NULL); + return ret; +} + +static void __exit caif_ser_exit(void) +{ + spin_lock(&ser_lock); + list_splice(&ser_list, &ser_release_list); + spin_unlock(&ser_lock); + ser_release(NULL); + cancel_work_sync(&ser_release_work); + tty_unregister_ldisc(N_CAIF); + debugfs_remove_recursive(debugfsdir); +} + +module_init(caif_ser_init); +module_exit(caif_ser_exit); diff --git a/drivers/net/caif/caif_spi.c b/drivers/net/caif/caif_spi.c new file mode 100644 index 000000000..d28a1398c --- /dev/null +++ b/drivers/net/caif/caif_spi.c @@ -0,0 +1,872 @@ +/* + * Copyright (C) ST-Ericsson AB 2010 + * Author: Daniel Martensson + * License terms: GNU General Public License (GPL) version 2. + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/platform_device.h> +#include <linux/string.h> +#include <linux/workqueue.h> +#include <linux/completion.h> +#include <linux/list.h> +#include <linux/interrupt.h> +#include <linux/dma-mapping.h> +#include <linux/delay.h> +#include <linux/sched.h> +#include <linux/debugfs.h> +#include <linux/if_arp.h> +#include <net/caif/caif_layer.h> +#include <net/caif/caif_spi.h> + +#ifndef CONFIG_CAIF_SPI_SYNC +#define FLAVOR "Flavour: Vanilla.\n" +#else +#define FLAVOR "Flavour: Master CMD&LEN at start.\n" +#endif /* CONFIG_CAIF_SPI_SYNC */ + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Daniel Martensson"); +MODULE_DESCRIPTION("CAIF SPI driver"); + +/* Returns the number of padding bytes for alignment. */ +#define PAD_POW2(x, pow) ((((x)&((pow)-1))==0) ? 0 : (((pow)-((x)&((pow)-1))))) + +static bool spi_loop; +module_param(spi_loop, bool, 0444); +MODULE_PARM_DESC(spi_loop, "SPI running in loopback mode."); + +/* SPI frame alignment. */ +module_param(spi_frm_align, int, 0444); +MODULE_PARM_DESC(spi_frm_align, "SPI frame alignment."); + +/* + * SPI padding options. + * Warning: must be a base of 2 (& operation used) and can not be zero ! + */ +module_param(spi_up_head_align, int, 0444); +MODULE_PARM_DESC(spi_up_head_align, "SPI uplink head alignment."); + +module_param(spi_up_tail_align, int, 0444); +MODULE_PARM_DESC(spi_up_tail_align, "SPI uplink tail alignment."); + +module_param(spi_down_head_align, int, 0444); +MODULE_PARM_DESC(spi_down_head_align, "SPI downlink head alignment."); + +module_param(spi_down_tail_align, int, 0444); +MODULE_PARM_DESC(spi_down_tail_align, "SPI downlink tail alignment."); + +#ifdef CONFIG_ARM +#define BYTE_HEX_FMT "%02X" +#else +#define BYTE_HEX_FMT "%02hhX" +#endif + +#define SPI_MAX_PAYLOAD_SIZE 4096 +/* + * Threshold values for the SPI packet queue. Flowcontrol will be asserted + * when the number of packets exceeds HIGH_WATER_MARK. It will not be + * deasserted before the number of packets drops below LOW_WATER_MARK. + */ +#define LOW_WATER_MARK 100 +#define HIGH_WATER_MARK (LOW_WATER_MARK*5) + +#ifdef CONFIG_UML + +/* + * We sometimes use UML for debugging, but it cannot handle + * dma_alloc_coherent so we have to wrap it. + */ +static inline void *dma_alloc(dma_addr_t *daddr) +{ + return kmalloc(SPI_DMA_BUF_LEN, GFP_KERNEL); +} + +static inline void dma_free(void *cpu_addr, dma_addr_t handle) +{ + kfree(cpu_addr); +} + +#else + +static inline void *dma_alloc(dma_addr_t *daddr) +{ + return dma_alloc_coherent(NULL, SPI_DMA_BUF_LEN, daddr, + GFP_KERNEL); +} + +static inline void dma_free(void *cpu_addr, dma_addr_t handle) +{ + dma_free_coherent(NULL, SPI_DMA_BUF_LEN, cpu_addr, handle); +} +#endif /* CONFIG_UML */ + +#ifdef CONFIG_DEBUG_FS + +#define DEBUGFS_BUF_SIZE 4096 + +static struct dentry *dbgfs_root; + +static inline void driver_debugfs_create(void) +{ + dbgfs_root = debugfs_create_dir(cfspi_spi_driver.driver.name, NULL); +} + +static inline void driver_debugfs_remove(void) +{ + debugfs_remove(dbgfs_root); +} + +static inline void dev_debugfs_rem(struct cfspi *cfspi) +{ + debugfs_remove(cfspi->dbgfs_frame); + debugfs_remove(cfspi->dbgfs_state); + debugfs_remove(cfspi->dbgfs_dir); +} + +static ssize_t dbgfs_state(struct file *file, char __user *user_buf, + size_t count, loff_t *ppos) +{ + char *buf; + int len = 0; + ssize_t size; + struct cfspi *cfspi = file->private_data; + + buf = kzalloc(DEBUGFS_BUF_SIZE, GFP_KERNEL); + if (!buf) + return 0; + + /* Print out debug information. */ + len += snprintf((buf + len), (DEBUGFS_BUF_SIZE - len), + "CAIF SPI debug information:\n"); + + len += snprintf((buf + len), (DEBUGFS_BUF_SIZE - len), FLAVOR); + + len += snprintf((buf + len), (DEBUGFS_BUF_SIZE - len), + "STATE: %d\n", cfspi->dbg_state); + len += snprintf((buf + len), (DEBUGFS_BUF_SIZE - len), + "Previous CMD: 0x%x\n", cfspi->pcmd); + len += snprintf((buf + len), (DEBUGFS_BUF_SIZE - len), + "Current CMD: 0x%x\n", cfspi->cmd); + len += snprintf((buf + len), (DEBUGFS_BUF_SIZE - len), + "Previous TX len: %d\n", cfspi->tx_ppck_len); + len += snprintf((buf + len), (DEBUGFS_BUF_SIZE - len), + "Previous RX len: %d\n", cfspi->rx_ppck_len); + len += snprintf((buf + len), (DEBUGFS_BUF_SIZE - len), + "Current TX len: %d\n", cfspi->tx_cpck_len); + len += snprintf((buf + len), (DEBUGFS_BUF_SIZE - len), + "Current RX len: %d\n", cfspi->rx_cpck_len); + len += snprintf((buf + len), (DEBUGFS_BUF_SIZE - len), + "Next TX len: %d\n", cfspi->tx_npck_len); + len += snprintf((buf + len), (DEBUGFS_BUF_SIZE - len), + "Next RX len: %d\n", cfspi->rx_npck_len); + + if (len > DEBUGFS_BUF_SIZE) + len = DEBUGFS_BUF_SIZE; + + size = simple_read_from_buffer(user_buf, count, ppos, buf, len); + kfree(buf); + + return size; +} + +static ssize_t print_frame(char *buf, size_t size, char *frm, + size_t count, size_t cut) +{ + int len = 0; + int i; + for (i = 0; i < count; i++) { + len += snprintf((buf + len), (size - len), + "[0x" BYTE_HEX_FMT "]", + frm[i]); + if ((i == cut) && (count > (cut * 2))) { + /* Fast forward. */ + i = count - cut; + len += snprintf((buf + len), (size - len), + "--- %zu bytes skipped ---\n", + count - (cut * 2)); + } + + if ((!(i % 10)) && i) { + len += snprintf((buf + len), (DEBUGFS_BUF_SIZE - len), + "\n"); + } + } + len += snprintf((buf + len), (DEBUGFS_BUF_SIZE - len), "\n"); + return len; +} + +static ssize_t dbgfs_frame(struct file *file, char __user *user_buf, + size_t count, loff_t *ppos) +{ + char *buf; + int len = 0; + ssize_t size; + struct cfspi *cfspi; + + cfspi = file->private_data; + buf = kzalloc(DEBUGFS_BUF_SIZE, GFP_KERNEL); + if (!buf) + return 0; + + /* Print out debug information. */ + len += snprintf((buf + len), (DEBUGFS_BUF_SIZE - len), + "Current frame:\n"); + + len += snprintf((buf + len), (DEBUGFS_BUF_SIZE - len), + "Tx data (Len: %d):\n", cfspi->tx_cpck_len); + + len += print_frame((buf + len), (DEBUGFS_BUF_SIZE - len), + cfspi->xfer.va_tx[0], + (cfspi->tx_cpck_len + SPI_CMD_SZ), 100); + + len += snprintf((buf + len), (DEBUGFS_BUF_SIZE - len), + "Rx data (Len: %d):\n", cfspi->rx_cpck_len); + + len += print_frame((buf + len), (DEBUGFS_BUF_SIZE - len), + cfspi->xfer.va_rx, + (cfspi->rx_cpck_len + SPI_CMD_SZ), 100); + + size = simple_read_from_buffer(user_buf, count, ppos, buf, len); + kfree(buf); + + return size; +} + +static const struct file_operations dbgfs_state_fops = { + .open = simple_open, + .read = dbgfs_state, + .owner = THIS_MODULE +}; + +static const struct file_operations dbgfs_frame_fops = { + .open = simple_open, + .read = dbgfs_frame, + .owner = THIS_MODULE +}; + +static inline void dev_debugfs_add(struct cfspi *cfspi) +{ + cfspi->dbgfs_dir = debugfs_create_dir(cfspi->pdev->name, dbgfs_root); + cfspi->dbgfs_state = debugfs_create_file("state", 0444, + cfspi->dbgfs_dir, cfspi, + &dbgfs_state_fops); + cfspi->dbgfs_frame = debugfs_create_file("frame", 0444, + cfspi->dbgfs_dir, cfspi, + &dbgfs_frame_fops); +} + +inline void cfspi_dbg_state(struct cfspi *cfspi, int state) +{ + cfspi->dbg_state = state; +}; +#else + +static inline void driver_debugfs_create(void) +{ +} + +static inline void driver_debugfs_remove(void) +{ +} + +static inline void dev_debugfs_add(struct cfspi *cfspi) +{ +} + +static inline void dev_debugfs_rem(struct cfspi *cfspi) +{ +} + +inline void cfspi_dbg_state(struct cfspi *cfspi, int state) +{ +} +#endif /* CONFIG_DEBUG_FS */ + +static LIST_HEAD(cfspi_list); +static spinlock_t cfspi_list_lock; + +/* SPI uplink head alignment. */ +static ssize_t up_head_align_show(struct device_driver *driver, char *buf) +{ + return sprintf(buf, "%d\n", spi_up_head_align); +} + +static DRIVER_ATTR_RO(up_head_align); + +/* SPI uplink tail alignment. */ +static ssize_t up_tail_align_show(struct device_driver *driver, char *buf) +{ + return sprintf(buf, "%d\n", spi_up_tail_align); +} + +static DRIVER_ATTR_RO(up_tail_align); + +/* SPI downlink head alignment. */ +static ssize_t down_head_align_show(struct device_driver *driver, char *buf) +{ + return sprintf(buf, "%d\n", spi_down_head_align); +} + +static DRIVER_ATTR_RO(down_head_align); + +/* SPI downlink tail alignment. */ +static ssize_t down_tail_align_show(struct device_driver *driver, char *buf) +{ + return sprintf(buf, "%d\n", spi_down_tail_align); +} + +static DRIVER_ATTR_RO(down_tail_align); + +/* SPI frame alignment. */ +static ssize_t frame_align_show(struct device_driver *driver, char *buf) +{ + return sprintf(buf, "%d\n", spi_frm_align); +} + +static DRIVER_ATTR_RO(frame_align); + +int cfspi_xmitfrm(struct cfspi *cfspi, u8 *buf, size_t len) +{ + u8 *dst = buf; + caif_assert(buf); + + if (cfspi->slave && !cfspi->slave_talked) + cfspi->slave_talked = true; + + do { + struct sk_buff *skb; + struct caif_payload_info *info; + int spad = 0; + int epad; + + skb = skb_dequeue(&cfspi->chead); + if (!skb) + break; + + /* + * Calculate length of frame including SPI padding. + * The payload position is found in the control buffer. + */ + info = (struct caif_payload_info *)&skb->cb; + + /* + * Compute head offset i.e. number of bytes to add to + * get the start of the payload aligned. + */ + if (spi_up_head_align > 1) { + spad = 1 + PAD_POW2((info->hdr_len + 1), spi_up_head_align); + *dst = (u8)(spad - 1); + dst += spad; + } + + /* Copy in CAIF frame. */ + skb_copy_bits(skb, 0, dst, skb->len); + dst += skb->len; + cfspi->ndev->stats.tx_packets++; + cfspi->ndev->stats.tx_bytes += skb->len; + + /* + * Compute tail offset i.e. number of bytes to add to + * get the complete CAIF frame aligned. + */ + epad = PAD_POW2((skb->len + spad), spi_up_tail_align); + dst += epad; + + dev_kfree_skb(skb); + + } while ((dst - buf) < len); + + return dst - buf; +} + +int cfspi_xmitlen(struct cfspi *cfspi) +{ + struct sk_buff *skb = NULL; + int frm_len = 0; + int pkts = 0; + + /* + * Decommit previously committed frames. + * skb_queue_splice_tail(&cfspi->chead,&cfspi->qhead) + */ + while (skb_peek(&cfspi->chead)) { + skb = skb_dequeue_tail(&cfspi->chead); + skb_queue_head(&cfspi->qhead, skb); + } + + do { + struct caif_payload_info *info = NULL; + int spad = 0; + int epad = 0; + + skb = skb_dequeue(&cfspi->qhead); + if (!skb) + break; + + /* + * Calculate length of frame including SPI padding. + * The payload position is found in the control buffer. + */ + info = (struct caif_payload_info *)&skb->cb; + + /* + * Compute head offset i.e. number of bytes to add to + * get the start of the payload aligned. + */ + if (spi_up_head_align > 1) + spad = 1 + PAD_POW2((info->hdr_len + 1), spi_up_head_align); + + /* + * Compute tail offset i.e. number of bytes to add to + * get the complete CAIF frame aligned. + */ + epad = PAD_POW2((skb->len + spad), spi_up_tail_align); + + if ((skb->len + spad + epad + frm_len) <= CAIF_MAX_SPI_FRAME) { + skb_queue_tail(&cfspi->chead, skb); + pkts++; + frm_len += skb->len + spad + epad; + } else { + /* Put back packet. */ + skb_queue_head(&cfspi->qhead, skb); + break; + } + } while (pkts <= CAIF_MAX_SPI_PKTS); + + /* + * Send flow on if previously sent flow off + * and now go below the low water mark + */ + if (cfspi->flow_off_sent && cfspi->qhead.qlen < cfspi->qd_low_mark && + cfspi->cfdev.flowctrl) { + cfspi->flow_off_sent = 0; + cfspi->cfdev.flowctrl(cfspi->ndev, 1); + } + + return frm_len; +} + +static void cfspi_ss_cb(bool assert, struct cfspi_ifc *ifc) +{ + struct cfspi *cfspi = (struct cfspi *)ifc->priv; + + /* + * The slave device is the master on the link. Interrupts before the + * slave has transmitted are considered spurious. + */ + if (cfspi->slave && !cfspi->slave_talked) { + printk(KERN_WARNING "CFSPI: Spurious SS interrupt.\n"); + return; + } + + if (!in_interrupt()) + spin_lock(&cfspi->lock); + if (assert) { + set_bit(SPI_SS_ON, &cfspi->state); + set_bit(SPI_XFER, &cfspi->state); + } else { + set_bit(SPI_SS_OFF, &cfspi->state); + } + if (!in_interrupt()) + spin_unlock(&cfspi->lock); + + /* Wake up the xfer thread. */ + if (assert) + wake_up_interruptible(&cfspi->wait); +} + +static void cfspi_xfer_done_cb(struct cfspi_ifc *ifc) +{ + struct cfspi *cfspi = (struct cfspi *)ifc->priv; + + /* Transfer done, complete work queue */ + complete(&cfspi->comp); +} + +static int cfspi_xmit(struct sk_buff *skb, struct net_device *dev) +{ + struct cfspi *cfspi = NULL; + unsigned long flags; + if (!dev) + return -EINVAL; + + cfspi = netdev_priv(dev); + + skb_queue_tail(&cfspi->qhead, skb); + + spin_lock_irqsave(&cfspi->lock, flags); + if (!test_and_set_bit(SPI_XFER, &cfspi->state)) { + /* Wake up xfer thread. */ + wake_up_interruptible(&cfspi->wait); + } + spin_unlock_irqrestore(&cfspi->lock, flags); + + /* Send flow off if number of bytes is above high water mark */ + if (!cfspi->flow_off_sent && + cfspi->qhead.qlen > cfspi->qd_high_mark && + cfspi->cfdev.flowctrl) { + cfspi->flow_off_sent = 1; + cfspi->cfdev.flowctrl(cfspi->ndev, 0); + } + + return 0; +} + +int cfspi_rxfrm(struct cfspi *cfspi, u8 *buf, size_t len) +{ + u8 *src = buf; + + caif_assert(buf != NULL); + + do { + int res; + struct sk_buff *skb = NULL; + int spad = 0; + int epad = 0; + int pkt_len = 0; + + /* + * Compute head offset i.e. number of bytes added to + * get the start of the payload aligned. + */ + if (spi_down_head_align > 1) { + spad = 1 + *src; + src += spad; + } + + /* Read length of CAIF frame (little endian). */ + pkt_len = *src; + pkt_len |= ((*(src+1)) << 8) & 0xFF00; + pkt_len += 2; /* Add FCS fields. */ + + /* Get a suitable caif packet and copy in data. */ + + skb = netdev_alloc_skb(cfspi->ndev, pkt_len + 1); + caif_assert(skb != NULL); + + skb_put_data(skb, src, pkt_len); + src += pkt_len; + + skb->protocol = htons(ETH_P_CAIF); + skb_reset_mac_header(skb); + + /* + * Push received packet up the stack. + */ + if (!spi_loop) + res = netif_rx_ni(skb); + else + res = cfspi_xmit(skb, cfspi->ndev); + + if (!res) { + cfspi->ndev->stats.rx_packets++; + cfspi->ndev->stats.rx_bytes += pkt_len; + } else + cfspi->ndev->stats.rx_dropped++; + + /* + * Compute tail offset i.e. number of bytes added to + * get the complete CAIF frame aligned. + */ + epad = PAD_POW2((pkt_len + spad), spi_down_tail_align); + src += epad; + } while ((src - buf) < len); + + return src - buf; +} + +static int cfspi_open(struct net_device *dev) +{ + netif_wake_queue(dev); + return 0; +} + +static int cfspi_close(struct net_device *dev) +{ + netif_stop_queue(dev); + return 0; +} + +static int cfspi_init(struct net_device *dev) +{ + int res = 0; + struct cfspi *cfspi = netdev_priv(dev); + + /* Set flow info. */ + cfspi->flow_off_sent = 0; + cfspi->qd_low_mark = LOW_WATER_MARK; + cfspi->qd_high_mark = HIGH_WATER_MARK; + + /* Set slave info. */ + if (!strncmp(cfspi_spi_driver.driver.name, "cfspi_sspi", 10)) { + cfspi->slave = true; + cfspi->slave_talked = false; + } else { + cfspi->slave = false; + cfspi->slave_talked = false; + } + + /* Allocate DMA buffers. */ + cfspi->xfer.va_tx[0] = dma_alloc(&cfspi->xfer.pa_tx[0]); + if (!cfspi->xfer.va_tx[0]) { + res = -ENODEV; + goto err_dma_alloc_tx_0; + } + + cfspi->xfer.va_rx = dma_alloc(&cfspi->xfer.pa_rx); + + if (!cfspi->xfer.va_rx) { + res = -ENODEV; + goto err_dma_alloc_rx; + } + + /* Initialize the work queue. */ + INIT_WORK(&cfspi->work, cfspi_xfer); + + /* Initialize spin locks. */ + spin_lock_init(&cfspi->lock); + + /* Initialize flow control state. */ + cfspi->flow_stop = false; + + /* Initialize wait queue. */ + init_waitqueue_head(&cfspi->wait); + + /* Create work thread. */ + cfspi->wq = create_singlethread_workqueue(dev->name); + if (!cfspi->wq) { + printk(KERN_WARNING "CFSPI: failed to create work queue.\n"); + res = -ENODEV; + goto err_create_wq; + } + + /* Initialize work queue. */ + init_completion(&cfspi->comp); + + /* Create debugfs entries. */ + dev_debugfs_add(cfspi); + + /* Set up the ifc. */ + cfspi->ifc.ss_cb = cfspi_ss_cb; + cfspi->ifc.xfer_done_cb = cfspi_xfer_done_cb; + cfspi->ifc.priv = cfspi; + + /* Add CAIF SPI device to list. */ + spin_lock(&cfspi_list_lock); + list_add_tail(&cfspi->list, &cfspi_list); + spin_unlock(&cfspi_list_lock); + + /* Schedule the work queue. */ + queue_work(cfspi->wq, &cfspi->work); + + return 0; + + err_create_wq: + dma_free(cfspi->xfer.va_rx, cfspi->xfer.pa_rx); + err_dma_alloc_rx: + dma_free(cfspi->xfer.va_tx[0], cfspi->xfer.pa_tx[0]); + err_dma_alloc_tx_0: + return res; +} + +static void cfspi_uninit(struct net_device *dev) +{ + struct cfspi *cfspi = netdev_priv(dev); + + /* Remove from list. */ + spin_lock(&cfspi_list_lock); + list_del(&cfspi->list); + spin_unlock(&cfspi_list_lock); + + cfspi->ndev = NULL; + /* Free DMA buffers. */ + dma_free(cfspi->xfer.va_rx, cfspi->xfer.pa_rx); + dma_free(cfspi->xfer.va_tx[0], cfspi->xfer.pa_tx[0]); + set_bit(SPI_TERMINATE, &cfspi->state); + wake_up_interruptible(&cfspi->wait); + destroy_workqueue(cfspi->wq); + /* Destroy debugfs directory and files. */ + dev_debugfs_rem(cfspi); + return; +} + +static const struct net_device_ops cfspi_ops = { + .ndo_open = cfspi_open, + .ndo_stop = cfspi_close, + .ndo_init = cfspi_init, + .ndo_uninit = cfspi_uninit, + .ndo_start_xmit = cfspi_xmit +}; + +static void cfspi_setup(struct net_device *dev) +{ + struct cfspi *cfspi = netdev_priv(dev); + dev->features = 0; + dev->netdev_ops = &cfspi_ops; + dev->type = ARPHRD_CAIF; + dev->flags = IFF_NOARP | IFF_POINTOPOINT; + dev->priv_flags |= IFF_NO_QUEUE; + dev->mtu = SPI_MAX_PAYLOAD_SIZE; + dev->needs_free_netdev = true; + skb_queue_head_init(&cfspi->qhead); + skb_queue_head_init(&cfspi->chead); + cfspi->cfdev.link_select = CAIF_LINK_HIGH_BANDW; + cfspi->cfdev.use_frag = false; + cfspi->cfdev.use_stx = false; + cfspi->cfdev.use_fcs = false; + cfspi->ndev = dev; +} + +int cfspi_spi_probe(struct platform_device *pdev) +{ + struct cfspi *cfspi = NULL; + struct net_device *ndev; + struct cfspi_dev *dev; + int res; + dev = (struct cfspi_dev *)pdev->dev.platform_data; + + if (!dev) + return -ENODEV; + + ndev = alloc_netdev(sizeof(struct cfspi), "cfspi%d", + NET_NAME_UNKNOWN, cfspi_setup); + if (!ndev) + return -ENOMEM; + + cfspi = netdev_priv(ndev); + netif_stop_queue(ndev); + cfspi->ndev = ndev; + cfspi->pdev = pdev; + + /* Assign the SPI device. */ + cfspi->dev = dev; + /* Assign the device ifc to this SPI interface. */ + dev->ifc = &cfspi->ifc; + + /* Register network device. */ + res = register_netdev(ndev); + if (res) { + printk(KERN_ERR "CFSPI: Reg. error: %d.\n", res); + goto err_net_reg; + } + return res; + + err_net_reg: + free_netdev(ndev); + + return res; +} + +int cfspi_spi_remove(struct platform_device *pdev) +{ + /* Everything is done in cfspi_uninit(). */ + return 0; +} + +static void __exit cfspi_exit_module(void) +{ + struct list_head *list_node; + struct list_head *n; + struct cfspi *cfspi = NULL; + + list_for_each_safe(list_node, n, &cfspi_list) { + cfspi = list_entry(list_node, struct cfspi, list); + unregister_netdev(cfspi->ndev); + } + + /* Destroy sysfs files. */ + driver_remove_file(&cfspi_spi_driver.driver, + &driver_attr_up_head_align); + driver_remove_file(&cfspi_spi_driver.driver, + &driver_attr_up_tail_align); + driver_remove_file(&cfspi_spi_driver.driver, + &driver_attr_down_head_align); + driver_remove_file(&cfspi_spi_driver.driver, + &driver_attr_down_tail_align); + driver_remove_file(&cfspi_spi_driver.driver, &driver_attr_frame_align); + /* Unregister platform driver. */ + platform_driver_unregister(&cfspi_spi_driver); + /* Destroy debugfs root directory. */ + driver_debugfs_remove(); +} + +static int __init cfspi_init_module(void) +{ + int result; + + /* Initialize spin lock. */ + spin_lock_init(&cfspi_list_lock); + + /* Register platform driver. */ + result = platform_driver_register(&cfspi_spi_driver); + if (result) { + printk(KERN_ERR "Could not register platform SPI driver.\n"); + goto err_dev_register; + } + + /* Create sysfs files. */ + result = + driver_create_file(&cfspi_spi_driver.driver, + &driver_attr_up_head_align); + if (result) { + printk(KERN_ERR "Sysfs creation failed 1.\n"); + goto err_create_up_head_align; + } + + result = + driver_create_file(&cfspi_spi_driver.driver, + &driver_attr_up_tail_align); + if (result) { + printk(KERN_ERR "Sysfs creation failed 2.\n"); + goto err_create_up_tail_align; + } + + result = + driver_create_file(&cfspi_spi_driver.driver, + &driver_attr_down_head_align); + if (result) { + printk(KERN_ERR "Sysfs creation failed 3.\n"); + goto err_create_down_head_align; + } + + result = + driver_create_file(&cfspi_spi_driver.driver, + &driver_attr_down_tail_align); + if (result) { + printk(KERN_ERR "Sysfs creation failed 4.\n"); + goto err_create_down_tail_align; + } + + result = + driver_create_file(&cfspi_spi_driver.driver, + &driver_attr_frame_align); + if (result) { + printk(KERN_ERR "Sysfs creation failed 5.\n"); + goto err_create_frame_align; + } + driver_debugfs_create(); + return result; + + err_create_frame_align: + driver_remove_file(&cfspi_spi_driver.driver, + &driver_attr_down_tail_align); + err_create_down_tail_align: + driver_remove_file(&cfspi_spi_driver.driver, + &driver_attr_down_head_align); + err_create_down_head_align: + driver_remove_file(&cfspi_spi_driver.driver, + &driver_attr_up_tail_align); + err_create_up_tail_align: + driver_remove_file(&cfspi_spi_driver.driver, + &driver_attr_up_head_align); + err_create_up_head_align: + platform_driver_unregister(&cfspi_spi_driver); + err_dev_register: + return result; +} + +module_init(cfspi_init_module); +module_exit(cfspi_exit_module); diff --git a/drivers/net/caif/caif_spi_slave.c b/drivers/net/caif/caif_spi_slave.c new file mode 100644 index 000000000..39ba2f892 --- /dev/null +++ b/drivers/net/caif/caif_spi_slave.c @@ -0,0 +1,254 @@ +/* + * Copyright (C) ST-Ericsson AB 2010 + * Author: Daniel Martensson + * License terms: GNU General Public License (GPL) version 2. + */ +#include <linux/module.h> +#include <linux/device.h> +#include <linux/platform_device.h> +#include <linux/string.h> +#include <linux/semaphore.h> +#include <linux/workqueue.h> +#include <linux/completion.h> +#include <linux/list.h> +#include <linux/interrupt.h> +#include <linux/dma-mapping.h> +#include <linux/delay.h> +#include <linux/sched.h> +#include <linux/debugfs.h> +#include <net/caif/caif_spi.h> + +#ifndef CONFIG_CAIF_SPI_SYNC +#define SPI_DATA_POS 0 +static inline int forward_to_spi_cmd(struct cfspi *cfspi) +{ + return cfspi->rx_cpck_len; +} +#else +#define SPI_DATA_POS SPI_CMD_SZ +static inline int forward_to_spi_cmd(struct cfspi *cfspi) +{ + return 0; +} +#endif + +int spi_frm_align = 2; + +/* + * SPI padding options. + * Warning: must be a base of 2 (& operation used) and can not be zero ! + */ +int spi_up_head_align = 1 << 1; +int spi_up_tail_align = 1 << 0; +int spi_down_head_align = 1 << 2; +int spi_down_tail_align = 1 << 1; + +#ifdef CONFIG_DEBUG_FS +static inline void debugfs_store_prev(struct cfspi *cfspi) +{ + /* Store previous command for debugging reasons.*/ + cfspi->pcmd = cfspi->cmd; + /* Store previous transfer. */ + cfspi->tx_ppck_len = cfspi->tx_cpck_len; + cfspi->rx_ppck_len = cfspi->rx_cpck_len; +} +#else +static inline void debugfs_store_prev(struct cfspi *cfspi) +{ +} +#endif + +void cfspi_xfer(struct work_struct *work) +{ + struct cfspi *cfspi; + u8 *ptr = NULL; + unsigned long flags; + int ret; + cfspi = container_of(work, struct cfspi, work); + + /* Initialize state. */ + cfspi->cmd = SPI_CMD_EOT; + + for (;;) { + + cfspi_dbg_state(cfspi, CFSPI_STATE_WAITING); + + /* Wait for master talk or transmit event. */ + wait_event_interruptible(cfspi->wait, + test_bit(SPI_XFER, &cfspi->state) || + test_bit(SPI_TERMINATE, &cfspi->state)); + + if (test_bit(SPI_TERMINATE, &cfspi->state)) + return; + +#if CFSPI_DBG_PREFILL + /* Prefill buffers for easier debugging. */ + memset(cfspi->xfer.va_tx, 0xFF, SPI_DMA_BUF_LEN); + memset(cfspi->xfer.va_rx, 0xFF, SPI_DMA_BUF_LEN); +#endif /* CFSPI_DBG_PREFILL */ + + cfspi_dbg_state(cfspi, CFSPI_STATE_AWAKE); + + /* Check whether we have a committed frame. */ + if (cfspi->tx_cpck_len) { + int len; + + cfspi_dbg_state(cfspi, CFSPI_STATE_FETCH_PKT); + + /* Copy committed SPI frames after the SPI indication. */ + ptr = (u8 *) cfspi->xfer.va_tx; + ptr += SPI_IND_SZ; + len = cfspi_xmitfrm(cfspi, ptr, cfspi->tx_cpck_len); + WARN_ON(len != cfspi->tx_cpck_len); + } + + cfspi_dbg_state(cfspi, CFSPI_STATE_GET_NEXT); + + /* Get length of next frame to commit. */ + cfspi->tx_npck_len = cfspi_xmitlen(cfspi); + + WARN_ON(cfspi->tx_npck_len > SPI_DMA_BUF_LEN); + + /* + * Add indication and length at the beginning of the frame, + * using little endian. + */ + ptr = (u8 *) cfspi->xfer.va_tx; + *ptr++ = SPI_CMD_IND; + *ptr++ = (SPI_CMD_IND & 0xFF00) >> 8; + *ptr++ = cfspi->tx_npck_len & 0x00FF; + *ptr++ = (cfspi->tx_npck_len & 0xFF00) >> 8; + + /* Calculate length of DMAs. */ + cfspi->xfer.tx_dma_len = cfspi->tx_cpck_len + SPI_IND_SZ; + cfspi->xfer.rx_dma_len = cfspi->rx_cpck_len + SPI_CMD_SZ; + + /* Add SPI TX frame alignment padding, if necessary. */ + if (cfspi->tx_cpck_len && + (cfspi->xfer.tx_dma_len % spi_frm_align)) { + + cfspi->xfer.tx_dma_len += spi_frm_align - + (cfspi->xfer.tx_dma_len % spi_frm_align); + } + + /* Add SPI RX frame alignment padding, if necessary. */ + if (cfspi->rx_cpck_len && + (cfspi->xfer.rx_dma_len % spi_frm_align)) { + + cfspi->xfer.rx_dma_len += spi_frm_align - + (cfspi->xfer.rx_dma_len % spi_frm_align); + } + + cfspi_dbg_state(cfspi, CFSPI_STATE_INIT_XFER); + + /* Start transfer. */ + ret = cfspi->dev->init_xfer(&cfspi->xfer, cfspi->dev); + WARN_ON(ret); + + cfspi_dbg_state(cfspi, CFSPI_STATE_WAIT_ACTIVE); + + /* + * TODO: We might be able to make an assumption if this is the + * first loop. Make sure that minimum toggle time is respected. + */ + udelay(MIN_TRANSITION_TIME_USEC); + + cfspi_dbg_state(cfspi, CFSPI_STATE_SIG_ACTIVE); + + /* Signal that we are ready to receive data. */ + cfspi->dev->sig_xfer(true, cfspi->dev); + + cfspi_dbg_state(cfspi, CFSPI_STATE_WAIT_XFER_DONE); + + /* Wait for transfer completion. */ + wait_for_completion(&cfspi->comp); + + cfspi_dbg_state(cfspi, CFSPI_STATE_XFER_DONE); + + if (cfspi->cmd == SPI_CMD_EOT) { + /* + * Clear the master talk bit. A xfer is always at + * least two bursts. + */ + clear_bit(SPI_SS_ON, &cfspi->state); + } + + cfspi_dbg_state(cfspi, CFSPI_STATE_WAIT_INACTIVE); + + /* Make sure that the minimum toggle time is respected. */ + if (SPI_XFER_TIME_USEC(cfspi->xfer.tx_dma_len, + cfspi->dev->clk_mhz) < + MIN_TRANSITION_TIME_USEC) { + + udelay(MIN_TRANSITION_TIME_USEC - + SPI_XFER_TIME_USEC + (cfspi->xfer.tx_dma_len, cfspi->dev->clk_mhz)); + } + + cfspi_dbg_state(cfspi, CFSPI_STATE_SIG_INACTIVE); + + /* De-assert transfer signal. */ + cfspi->dev->sig_xfer(false, cfspi->dev); + + /* Check whether we received a CAIF packet. */ + if (cfspi->rx_cpck_len) { + int len; + + cfspi_dbg_state(cfspi, CFSPI_STATE_DELIVER_PKT); + + /* Parse SPI frame. */ + ptr = ((u8 *)(cfspi->xfer.va_rx + SPI_DATA_POS)); + + len = cfspi_rxfrm(cfspi, ptr, cfspi->rx_cpck_len); + WARN_ON(len != cfspi->rx_cpck_len); + } + + /* Check the next SPI command and length. */ + ptr = (u8 *) cfspi->xfer.va_rx; + + ptr += forward_to_spi_cmd(cfspi); + + cfspi->cmd = *ptr++; + cfspi->cmd |= ((*ptr++) << 8) & 0xFF00; + cfspi->rx_npck_len = *ptr++; + cfspi->rx_npck_len |= ((*ptr++) << 8) & 0xFF00; + + WARN_ON(cfspi->rx_npck_len > SPI_DMA_BUF_LEN); + WARN_ON(cfspi->cmd > SPI_CMD_EOT); + + debugfs_store_prev(cfspi); + + /* Check whether the master issued an EOT command. */ + if (cfspi->cmd == SPI_CMD_EOT) { + /* Reset state. */ + cfspi->tx_cpck_len = 0; + cfspi->rx_cpck_len = 0; + } else { + /* Update state. */ + cfspi->tx_cpck_len = cfspi->tx_npck_len; + cfspi->rx_cpck_len = cfspi->rx_npck_len; + } + + /* + * Check whether we need to clear the xfer bit. + * Spin lock needed for packet insertion. + * Test and clear of different bits + * are not supported. + */ + spin_lock_irqsave(&cfspi->lock, flags); + if (cfspi->cmd == SPI_CMD_EOT && !cfspi_xmitlen(cfspi) + && !test_bit(SPI_SS_ON, &cfspi->state)) + clear_bit(SPI_XFER, &cfspi->state); + + spin_unlock_irqrestore(&cfspi->lock, flags); + } +} + +struct platform_driver cfspi_spi_driver = { + .probe = cfspi_spi_probe, + .remove = cfspi_spi_remove, + .driver = { + .name = "cfspi_sspi", + .owner = THIS_MODULE, + }, +}; diff --git a/drivers/net/caif/caif_virtio.c b/drivers/net/caif/caif_virtio.c new file mode 100644 index 000000000..2814e0dee --- /dev/null +++ b/drivers/net/caif/caif_virtio.c @@ -0,0 +1,789 @@ +/* + * Copyright (C) ST-Ericsson AB 2013 + * Authors: Vicram Arv + * Dmitry Tarnyagin <dmitry.tarnyagin@lockless.no> + * Sjur Brendeland + * License terms: GNU General Public License (GPL) version 2 + */ +#include <linux/module.h> +#include <linux/if_arp.h> +#include <linux/virtio.h> +#include <linux/vringh.h> +#include <linux/debugfs.h> +#include <linux/spinlock.h> +#include <linux/genalloc.h> +#include <linux/interrupt.h> +#include <linux/netdevice.h> +#include <linux/rtnetlink.h> +#include <linux/virtio_ids.h> +#include <linux/virtio_caif.h> +#include <linux/virtio_ring.h> +#include <linux/dma-mapping.h> +#include <net/caif/caif_dev.h> +#include <linux/virtio_config.h> + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Vicram Arv"); +MODULE_AUTHOR("Sjur Brendeland"); +MODULE_DESCRIPTION("Virtio CAIF Driver"); + +/* NAPI schedule quota */ +#define CFV_DEFAULT_QUOTA 32 + +/* Defaults used if virtio config space is unavailable */ +#define CFV_DEF_MTU_SIZE 4096 +#define CFV_DEF_HEADROOM 32 +#define CFV_DEF_TAILROOM 32 + +/* Required IP header alignment */ +#define IP_HDR_ALIGN 4 + +/* struct cfv_napi_contxt - NAPI context info + * @riov: IOV holding data read from the ring. Note that riov may + * still hold data when cfv_rx_poll() returns. + * @head: Last descriptor ID we received from vringh_getdesc_kern. + * We use this to put descriptor back on the used ring. USHRT_MAX is + * used to indicate invalid head-id. + */ +struct cfv_napi_context { + struct vringh_kiov riov; + unsigned short head; +}; + +/* struct cfv_stats - statistics for debugfs + * @rx_napi_complete: Number of NAPI completions (RX) + * @rx_napi_resched: Number of calls where the full quota was used (RX) + * @rx_nomem: Number of SKB alloc failures (RX) + * @rx_kicks: Number of RX kicks + * @tx_full_ring: Number times TX ring was full + * @tx_no_mem: Number of times TX went out of memory + * @tx_flow_on: Number of flow on (TX) + * @tx_kicks: Number of TX kicks + */ +struct cfv_stats { + u32 rx_napi_complete; + u32 rx_napi_resched; + u32 rx_nomem; + u32 rx_kicks; + u32 tx_full_ring; + u32 tx_no_mem; + u32 tx_flow_on; + u32 tx_kicks; +}; + +/* struct cfv_info - Caif Virtio control structure + * @cfdev: caif common header + * @vdev: Associated virtio device + * @vr_rx: rx/downlink host vring + * @vq_tx: tx/uplink virtqueue + * @ndev: CAIF link layer device + * @watermark_tx: indicates number of free descriptors we need + * to reopen the tx-queues after overload. + * @tx_lock: protects vq_tx from concurrent use + * @tx_release_tasklet: Tasklet for freeing consumed TX buffers + * @napi: Napi context used in cfv_rx_poll() + * @ctx: Context data used in cfv_rx_poll() + * @tx_hr: transmit headroom + * @rx_hr: receive headroom + * @tx_tr: transmit tail room + * @rx_tr: receive tail room + * @mtu: transmit max size + * @mru: receive max size + * @allocsz: size of dma memory reserved for TX buffers + * @alloc_addr: virtual address to dma memory for TX buffers + * @alloc_dma: dma address to dma memory for TX buffers + * @genpool: Gen Pool used for allocating TX buffers + * @reserved_mem: Pointer to memory reserve allocated from genpool + * @reserved_size: Size of memory reserve allocated from genpool + * @stats: Statistics exposed in sysfs + * @debugfs: Debugfs dentry for statistic counters + */ +struct cfv_info { + struct caif_dev_common cfdev; + struct virtio_device *vdev; + struct vringh *vr_rx; + struct virtqueue *vq_tx; + struct net_device *ndev; + unsigned int watermark_tx; + /* Protect access to vq_tx */ + spinlock_t tx_lock; + struct tasklet_struct tx_release_tasklet; + struct napi_struct napi; + struct cfv_napi_context ctx; + u16 tx_hr; + u16 rx_hr; + u16 tx_tr; + u16 rx_tr; + u32 mtu; + u32 mru; + size_t allocsz; + void *alloc_addr; + dma_addr_t alloc_dma; + struct gen_pool *genpool; + unsigned long reserved_mem; + size_t reserved_size; + struct cfv_stats stats; + struct dentry *debugfs; +}; + +/* struct buf_info - maintains transmit buffer data handle + * @size: size of transmit buffer + * @dma_handle: handle to allocated dma device memory area + * @vaddr: virtual address mapping to allocated memory area + */ +struct buf_info { + size_t size; + u8 *vaddr; +}; + +/* Called from virtio device, in IRQ context */ +static void cfv_release_cb(struct virtqueue *vq_tx) +{ + struct cfv_info *cfv = vq_tx->vdev->priv; + + ++cfv->stats.tx_kicks; + tasklet_schedule(&cfv->tx_release_tasklet); +} + +static void free_buf_info(struct cfv_info *cfv, struct buf_info *buf_info) +{ + if (!buf_info) + return; + gen_pool_free(cfv->genpool, (unsigned long) buf_info->vaddr, + buf_info->size); + kfree(buf_info); +} + +/* This is invoked whenever the remote processor completed processing + * a TX msg we just sent, and the buffer is put back to the used ring. + */ +static void cfv_release_used_buf(struct virtqueue *vq_tx) +{ + struct cfv_info *cfv = vq_tx->vdev->priv; + unsigned long flags; + + BUG_ON(vq_tx != cfv->vq_tx); + + for (;;) { + unsigned int len; + struct buf_info *buf_info; + + /* Get used buffer from used ring to recycle used descriptors */ + spin_lock_irqsave(&cfv->tx_lock, flags); + buf_info = virtqueue_get_buf(vq_tx, &len); + spin_unlock_irqrestore(&cfv->tx_lock, flags); + + /* Stop looping if there are no more buffers to free */ + if (!buf_info) + break; + + free_buf_info(cfv, buf_info); + + /* watermark_tx indicates if we previously stopped the tx + * queues. If we have enough free stots in the virtio ring, + * re-establish memory reserved and open up tx queues. + */ + if (cfv->vq_tx->num_free <= cfv->watermark_tx) + continue; + + /* Re-establish memory reserve */ + if (cfv->reserved_mem == 0 && cfv->genpool) + cfv->reserved_mem = + gen_pool_alloc(cfv->genpool, + cfv->reserved_size); + + /* Open up the tx queues */ + if (cfv->reserved_mem) { + cfv->watermark_tx = + virtqueue_get_vring_size(cfv->vq_tx); + netif_tx_wake_all_queues(cfv->ndev); + /* Buffers are recycled in cfv_netdev_tx, so + * disable notifications when queues are opened. + */ + virtqueue_disable_cb(cfv->vq_tx); + ++cfv->stats.tx_flow_on; + } else { + /* if no memory reserve, wait for more free slots */ + WARN_ON(cfv->watermark_tx > + virtqueue_get_vring_size(cfv->vq_tx)); + cfv->watermark_tx += + virtqueue_get_vring_size(cfv->vq_tx) / 4; + } + } +} + +/* Allocate a SKB and copy packet data to it */ +static struct sk_buff *cfv_alloc_and_copy_skb(int *err, + struct cfv_info *cfv, + u8 *frm, u32 frm_len) +{ + struct sk_buff *skb; + u32 cfpkt_len, pad_len; + + *err = 0; + /* Verify that packet size with down-link header and mtu size */ + if (frm_len > cfv->mru || frm_len <= cfv->rx_hr + cfv->rx_tr) { + netdev_err(cfv->ndev, + "Invalid frmlen:%u mtu:%u hr:%d tr:%d\n", + frm_len, cfv->mru, cfv->rx_hr, + cfv->rx_tr); + *err = -EPROTO; + return NULL; + } + + cfpkt_len = frm_len - (cfv->rx_hr + cfv->rx_tr); + pad_len = (unsigned long)(frm + cfv->rx_hr) & (IP_HDR_ALIGN - 1); + + skb = netdev_alloc_skb(cfv->ndev, frm_len + pad_len); + if (!skb) { + *err = -ENOMEM; + return NULL; + } + + skb_reserve(skb, cfv->rx_hr + pad_len); + + skb_put_data(skb, frm + cfv->rx_hr, cfpkt_len); + return skb; +} + +/* Get packets from the host vring */ +static int cfv_rx_poll(struct napi_struct *napi, int quota) +{ + struct cfv_info *cfv = container_of(napi, struct cfv_info, napi); + int rxcnt = 0; + int err = 0; + void *buf; + struct sk_buff *skb; + struct vringh_kiov *riov = &cfv->ctx.riov; + unsigned int skb_len; + + do { + skb = NULL; + + /* Put the previous iovec back on the used ring and + * fetch a new iovec if we have processed all elements. + */ + if (riov->i == riov->used) { + if (cfv->ctx.head != USHRT_MAX) { + vringh_complete_kern(cfv->vr_rx, + cfv->ctx.head, + 0); + cfv->ctx.head = USHRT_MAX; + } + + err = vringh_getdesc_kern( + cfv->vr_rx, + riov, + NULL, + &cfv->ctx.head, + GFP_ATOMIC); + + if (err <= 0) + goto exit; + } + + buf = phys_to_virt((unsigned long) riov->iov[riov->i].iov_base); + /* TODO: Add check on valid buffer address */ + + skb = cfv_alloc_and_copy_skb(&err, cfv, buf, + riov->iov[riov->i].iov_len); + if (unlikely(err)) + goto exit; + + /* Push received packet up the stack. */ + skb_len = skb->len; + skb->protocol = htons(ETH_P_CAIF); + skb_reset_mac_header(skb); + skb->dev = cfv->ndev; + err = netif_receive_skb(skb); + if (unlikely(err)) { + ++cfv->ndev->stats.rx_dropped; + } else { + ++cfv->ndev->stats.rx_packets; + cfv->ndev->stats.rx_bytes += skb_len; + } + + ++riov->i; + ++rxcnt; + } while (rxcnt < quota); + + ++cfv->stats.rx_napi_resched; + goto out; + +exit: + switch (err) { + case 0: + ++cfv->stats.rx_napi_complete; + + /* Really out of patckets? (stolen from virtio_net)*/ + napi_complete(napi); + if (unlikely(!vringh_notify_enable_kern(cfv->vr_rx)) && + napi_schedule_prep(napi)) { + vringh_notify_disable_kern(cfv->vr_rx); + __napi_schedule(napi); + } + break; + + case -ENOMEM: + ++cfv->stats.rx_nomem; + dev_kfree_skb(skb); + /* Stop NAPI poll on OOM, we hope to be polled later */ + napi_complete(napi); + vringh_notify_enable_kern(cfv->vr_rx); + break; + + default: + /* We're doomed, any modem fault is fatal */ + netdev_warn(cfv->ndev, "Bad ring, disable device\n"); + cfv->ndev->stats.rx_dropped = riov->used - riov->i; + napi_complete(napi); + vringh_notify_disable_kern(cfv->vr_rx); + netif_carrier_off(cfv->ndev); + break; + } +out: + if (rxcnt && vringh_need_notify_kern(cfv->vr_rx) > 0) + vringh_notify(cfv->vr_rx); + return rxcnt; +} + +static void cfv_recv(struct virtio_device *vdev, struct vringh *vr_rx) +{ + struct cfv_info *cfv = vdev->priv; + + ++cfv->stats.rx_kicks; + vringh_notify_disable_kern(cfv->vr_rx); + napi_schedule(&cfv->napi); +} + +static void cfv_destroy_genpool(struct cfv_info *cfv) +{ + if (cfv->alloc_addr) + dma_free_coherent(cfv->vdev->dev.parent->parent, + cfv->allocsz, cfv->alloc_addr, + cfv->alloc_dma); + + if (!cfv->genpool) + return; + gen_pool_free(cfv->genpool, cfv->reserved_mem, + cfv->reserved_size); + gen_pool_destroy(cfv->genpool); + cfv->genpool = NULL; +} + +static int cfv_create_genpool(struct cfv_info *cfv) +{ + int err; + + /* dma_alloc can only allocate whole pages, and we need a more + * fine graned allocation so we use genpool. We ask for space needed + * by IP and a full ring. If the dma allcoation fails we retry with a + * smaller allocation size. + */ + err = -ENOMEM; + cfv->allocsz = (virtqueue_get_vring_size(cfv->vq_tx) * + (ETH_DATA_LEN + cfv->tx_hr + cfv->tx_tr) * 11)/10; + if (cfv->allocsz <= (num_possible_cpus() + 1) * cfv->ndev->mtu) + return -EINVAL; + + for (;;) { + if (cfv->allocsz <= num_possible_cpus() * cfv->ndev->mtu) { + netdev_info(cfv->ndev, "Not enough device memory\n"); + return -ENOMEM; + } + + cfv->alloc_addr = dma_alloc_coherent( + cfv->vdev->dev.parent->parent, + cfv->allocsz, &cfv->alloc_dma, + GFP_ATOMIC); + if (cfv->alloc_addr) + break; + + cfv->allocsz = (cfv->allocsz * 3) >> 2; + } + + netdev_dbg(cfv->ndev, "Allocated %zd bytes from dma-memory\n", + cfv->allocsz); + + /* Allocate on 128 bytes boundaries (1 << 7)*/ + cfv->genpool = gen_pool_create(7, -1); + if (!cfv->genpool) + goto err; + + err = gen_pool_add_virt(cfv->genpool, (unsigned long)cfv->alloc_addr, + (phys_addr_t)virt_to_phys(cfv->alloc_addr), + cfv->allocsz, -1); + if (err) + goto err; + + /* Reserve some memory for low memory situations. If we hit the roof + * in the memory pool, we stop TX flow and release the reserve. + */ + cfv->reserved_size = num_possible_cpus() * cfv->ndev->mtu; + cfv->reserved_mem = gen_pool_alloc(cfv->genpool, + cfv->reserved_size); + if (!cfv->reserved_mem) { + err = -ENOMEM; + goto err; + } + + cfv->watermark_tx = virtqueue_get_vring_size(cfv->vq_tx); + return 0; +err: + cfv_destroy_genpool(cfv); + return err; +} + +/* Enable the CAIF interface and allocate the memory-pool */ +static int cfv_netdev_open(struct net_device *netdev) +{ + struct cfv_info *cfv = netdev_priv(netdev); + + if (cfv_create_genpool(cfv)) + return -ENOMEM; + + netif_carrier_on(netdev); + napi_enable(&cfv->napi); + + /* Schedule NAPI to read any pending packets */ + napi_schedule(&cfv->napi); + return 0; +} + +/* Disable the CAIF interface and free the memory-pool */ +static int cfv_netdev_close(struct net_device *netdev) +{ + struct cfv_info *cfv = netdev_priv(netdev); + unsigned long flags; + struct buf_info *buf_info; + + /* Disable interrupts, queues and NAPI polling */ + netif_carrier_off(netdev); + virtqueue_disable_cb(cfv->vq_tx); + vringh_notify_disable_kern(cfv->vr_rx); + napi_disable(&cfv->napi); + + /* Release any TX buffers on both used and avilable rings */ + cfv_release_used_buf(cfv->vq_tx); + spin_lock_irqsave(&cfv->tx_lock, flags); + while ((buf_info = virtqueue_detach_unused_buf(cfv->vq_tx))) + free_buf_info(cfv, buf_info); + spin_unlock_irqrestore(&cfv->tx_lock, flags); + + /* Release all dma allocated memory and destroy the pool */ + cfv_destroy_genpool(cfv); + return 0; +} + +/* Allocate a buffer in dma-memory and copy skb to it */ +static struct buf_info *cfv_alloc_and_copy_to_shm(struct cfv_info *cfv, + struct sk_buff *skb, + struct scatterlist *sg) +{ + struct caif_payload_info *info = (void *)&skb->cb; + struct buf_info *buf_info = NULL; + u8 pad_len, hdr_ofs; + + if (!cfv->genpool) + goto err; + + if (unlikely(cfv->tx_hr + skb->len + cfv->tx_tr > cfv->mtu)) { + netdev_warn(cfv->ndev, "Invalid packet len (%d > %d)\n", + cfv->tx_hr + skb->len + cfv->tx_tr, cfv->mtu); + goto err; + } + + buf_info = kmalloc(sizeof(struct buf_info), GFP_ATOMIC); + if (unlikely(!buf_info)) + goto err; + + /* Make the IP header aligned in tbe buffer */ + hdr_ofs = cfv->tx_hr + info->hdr_len; + pad_len = hdr_ofs & (IP_HDR_ALIGN - 1); + buf_info->size = cfv->tx_hr + skb->len + cfv->tx_tr + pad_len; + + /* allocate dma memory buffer */ + buf_info->vaddr = (void *)gen_pool_alloc(cfv->genpool, buf_info->size); + if (unlikely(!buf_info->vaddr)) + goto err; + + /* copy skbuf contents to send buffer */ + skb_copy_bits(skb, 0, buf_info->vaddr + cfv->tx_hr + pad_len, skb->len); + sg_init_one(sg, buf_info->vaddr + pad_len, + skb->len + cfv->tx_hr + cfv->rx_hr); + + return buf_info; +err: + kfree(buf_info); + return NULL; +} + +/* Put the CAIF packet on the virtio ring and kick the receiver */ +static int cfv_netdev_tx(struct sk_buff *skb, struct net_device *netdev) +{ + struct cfv_info *cfv = netdev_priv(netdev); + struct buf_info *buf_info; + struct scatterlist sg; + unsigned long flags; + bool flow_off = false; + int ret; + + /* garbage collect released buffers */ + cfv_release_used_buf(cfv->vq_tx); + spin_lock_irqsave(&cfv->tx_lock, flags); + + /* Flow-off check takes into account number of cpus to make sure + * virtqueue will not be overfilled in any possible smp conditions. + * + * Flow-on is triggered when sufficient buffers are freed + */ + if (unlikely(cfv->vq_tx->num_free <= num_present_cpus())) { + flow_off = true; + cfv->stats.tx_full_ring++; + } + + /* If we run out of memory, we release the memory reserve and retry + * allocation. + */ + buf_info = cfv_alloc_and_copy_to_shm(cfv, skb, &sg); + if (unlikely(!buf_info)) { + cfv->stats.tx_no_mem++; + flow_off = true; + + if (cfv->reserved_mem && cfv->genpool) { + gen_pool_free(cfv->genpool, cfv->reserved_mem, + cfv->reserved_size); + cfv->reserved_mem = 0; + buf_info = cfv_alloc_and_copy_to_shm(cfv, skb, &sg); + } + } + + if (unlikely(flow_off)) { + /* Turn flow on when a 1/4 of the descriptors are released */ + cfv->watermark_tx = virtqueue_get_vring_size(cfv->vq_tx) / 4; + /* Enable notifications of recycled TX buffers */ + virtqueue_enable_cb(cfv->vq_tx); + netif_tx_stop_all_queues(netdev); + } + + if (unlikely(!buf_info)) { + /* If the memory reserve does it's job, this shouldn't happen */ + netdev_warn(cfv->ndev, "Out of gen_pool memory\n"); + goto err; + } + + ret = virtqueue_add_outbuf(cfv->vq_tx, &sg, 1, buf_info, GFP_ATOMIC); + if (unlikely((ret < 0))) { + /* If flow control works, this shouldn't happen */ + netdev_warn(cfv->ndev, "Failed adding buffer to TX vring:%d\n", + ret); + goto err; + } + + /* update netdev statistics */ + cfv->ndev->stats.tx_packets++; + cfv->ndev->stats.tx_bytes += skb->len; + spin_unlock_irqrestore(&cfv->tx_lock, flags); + + /* tell the remote processor it has a pending message to read */ + virtqueue_kick(cfv->vq_tx); + + dev_kfree_skb(skb); + return NETDEV_TX_OK; +err: + spin_unlock_irqrestore(&cfv->tx_lock, flags); + cfv->ndev->stats.tx_dropped++; + free_buf_info(cfv, buf_info); + dev_kfree_skb(skb); + return NETDEV_TX_OK; +} + +static void cfv_tx_release_tasklet(unsigned long drv) +{ + struct cfv_info *cfv = (struct cfv_info *)drv; + cfv_release_used_buf(cfv->vq_tx); +} + +static const struct net_device_ops cfv_netdev_ops = { + .ndo_open = cfv_netdev_open, + .ndo_stop = cfv_netdev_close, + .ndo_start_xmit = cfv_netdev_tx, +}; + +static void cfv_netdev_setup(struct net_device *netdev) +{ + netdev->netdev_ops = &cfv_netdev_ops; + netdev->type = ARPHRD_CAIF; + netdev->tx_queue_len = 100; + netdev->flags = IFF_POINTOPOINT | IFF_NOARP; + netdev->mtu = CFV_DEF_MTU_SIZE; + netdev->needs_free_netdev = true; +} + +/* Create debugfs counters for the device */ +static inline void debugfs_init(struct cfv_info *cfv) +{ + cfv->debugfs = + debugfs_create_dir(netdev_name(cfv->ndev), NULL); + + if (IS_ERR(cfv->debugfs)) + return; + + debugfs_create_u32("rx-napi-complete", 0400, cfv->debugfs, + &cfv->stats.rx_napi_complete); + debugfs_create_u32("rx-napi-resched", 0400, cfv->debugfs, + &cfv->stats.rx_napi_resched); + debugfs_create_u32("rx-nomem", 0400, cfv->debugfs, + &cfv->stats.rx_nomem); + debugfs_create_u32("rx-kicks", 0400, cfv->debugfs, + &cfv->stats.rx_kicks); + debugfs_create_u32("tx-full-ring", 0400, cfv->debugfs, + &cfv->stats.tx_full_ring); + debugfs_create_u32("tx-no-mem", 0400, cfv->debugfs, + &cfv->stats.tx_no_mem); + debugfs_create_u32("tx-kicks", 0400, cfv->debugfs, + &cfv->stats.tx_kicks); + debugfs_create_u32("tx-flow-on", 0400, cfv->debugfs, + &cfv->stats.tx_flow_on); +} + +/* Setup CAIF for the a virtio device */ +static int cfv_probe(struct virtio_device *vdev) +{ + vq_callback_t *vq_cbs = cfv_release_cb; + vrh_callback_t *vrh_cbs = cfv_recv; + const char *names = "output"; + const char *cfv_netdev_name = "cfvrt"; + struct net_device *netdev; + struct cfv_info *cfv; + int err = -EINVAL; + + netdev = alloc_netdev(sizeof(struct cfv_info), cfv_netdev_name, + NET_NAME_UNKNOWN, cfv_netdev_setup); + if (!netdev) + return -ENOMEM; + + cfv = netdev_priv(netdev); + cfv->vdev = vdev; + cfv->ndev = netdev; + + spin_lock_init(&cfv->tx_lock); + + /* Get the RX virtio ring. This is a "host side vring". */ + err = -ENODEV; + if (!vdev->vringh_config || !vdev->vringh_config->find_vrhs) + goto err; + + err = vdev->vringh_config->find_vrhs(vdev, 1, &cfv->vr_rx, &vrh_cbs); + if (err) + goto err; + + /* Get the TX virtio ring. This is a "guest side vring". */ + err = virtio_find_vqs(vdev, 1, &cfv->vq_tx, &vq_cbs, &names, NULL); + if (err) + goto err; + + /* Get the CAIF configuration from virtio config space, if available */ + if (vdev->config->get) { + virtio_cread(vdev, struct virtio_caif_transf_config, headroom, + &cfv->tx_hr); + virtio_cread(vdev, struct virtio_caif_transf_config, headroom, + &cfv->rx_hr); + virtio_cread(vdev, struct virtio_caif_transf_config, tailroom, + &cfv->tx_tr); + virtio_cread(vdev, struct virtio_caif_transf_config, tailroom, + &cfv->rx_tr); + virtio_cread(vdev, struct virtio_caif_transf_config, mtu, + &cfv->mtu); + virtio_cread(vdev, struct virtio_caif_transf_config, mtu, + &cfv->mru); + } else { + cfv->tx_hr = CFV_DEF_HEADROOM; + cfv->rx_hr = CFV_DEF_HEADROOM; + cfv->tx_tr = CFV_DEF_TAILROOM; + cfv->rx_tr = CFV_DEF_TAILROOM; + cfv->mtu = CFV_DEF_MTU_SIZE; + cfv->mru = CFV_DEF_MTU_SIZE; + } + + netdev->needed_headroom = cfv->tx_hr; + netdev->needed_tailroom = cfv->tx_tr; + + /* Disable buffer release interrupts unless we have stopped TX queues */ + virtqueue_disable_cb(cfv->vq_tx); + + netdev->mtu = cfv->mtu - cfv->tx_tr; + vdev->priv = cfv; + + /* Initialize NAPI poll context data */ + vringh_kiov_init(&cfv->ctx.riov, NULL, 0); + cfv->ctx.head = USHRT_MAX; + netif_napi_add(netdev, &cfv->napi, cfv_rx_poll, CFV_DEFAULT_QUOTA); + + tasklet_init(&cfv->tx_release_tasklet, + cfv_tx_release_tasklet, + (unsigned long)cfv); + + /* Carrier is off until netdevice is opened */ + netif_carrier_off(netdev); + + /* register Netdev */ + err = register_netdev(netdev); + if (err) { + dev_err(&vdev->dev, "Unable to register netdev (%d)\n", err); + goto err; + } + + debugfs_init(cfv); + + return 0; +err: + netdev_warn(cfv->ndev, "CAIF Virtio probe failed:%d\n", err); + + if (cfv->vr_rx) + vdev->vringh_config->del_vrhs(cfv->vdev); + if (cfv->vdev) + vdev->config->del_vqs(cfv->vdev); + free_netdev(netdev); + return err; +} + +static void cfv_remove(struct virtio_device *vdev) +{ + struct cfv_info *cfv = vdev->priv; + + rtnl_lock(); + dev_close(cfv->ndev); + rtnl_unlock(); + + tasklet_kill(&cfv->tx_release_tasklet); + debugfs_remove_recursive(cfv->debugfs); + + vringh_kiov_cleanup(&cfv->ctx.riov); + vdev->config->reset(vdev); + vdev->vringh_config->del_vrhs(cfv->vdev); + cfv->vr_rx = NULL; + vdev->config->del_vqs(cfv->vdev); + unregister_netdev(cfv->ndev); +} + +static struct virtio_device_id id_table[] = { + { VIRTIO_ID_CAIF, VIRTIO_DEV_ANY_ID }, + { 0 }, +}; + +static unsigned int features[] = { +}; + +static struct virtio_driver caif_virtio_driver = { + .feature_table = features, + .feature_table_size = ARRAY_SIZE(features), + .driver.name = KBUILD_MODNAME, + .driver.owner = THIS_MODULE, + .id_table = id_table, + .probe = cfv_probe, + .remove = cfv_remove, +}; + +module_virtio_driver(caif_virtio_driver); +MODULE_DEVICE_TABLE(virtio, id_table); |