WIP FPC-III support

[linux/fpc-iii.git] / drivers / net / wireless / intersil / prism54 / islpci_mgt.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 *  Copyright (C) 2002 Intersil Americas Inc.
 *  Copyright 2004 Jens Maurer <Jens.Maurer@gmx.net>
 */

#include <linux/netdevice.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/sched.h>
#include <linux/slab.h>

#include <asm/io.h>
#include <linux/if_arp.h>

#include "prismcompat.h"
#include "isl_38xx.h"
#include "islpci_mgt.h"
#include "isl_oid.h"            /* additional types and defs for isl38xx fw */
#include "isl_ioctl.h"

#include <net/iw_handler.h>

/******************************************************************************
        Global variable definition section
******************************************************************************/
int pc_debug = VERBOSE;
module_param(pc_debug, int, 0);

/******************************************************************************
    Driver general functions
******************************************************************************/
#if VERBOSE > SHOW_ERROR_MESSAGES
void
display_buffer(char *buffer, int length)
{
        if ((pc_debug & SHOW_BUFFER_CONTENTS) == 0)
                return;

        while (length > 0) {
                printk("[%02x]", *buffer & 255);
                length--;
                buffer++;
        }

        printk("\n");
}
#endif

/*****************************************************************************
    Queue handling for management frames
******************************************************************************/

/*
 * Helper function to create a PIMFOR management frame header.
 */
static void
pimfor_encode_header(int operation, u32 oid, u32 length, pimfor_header_t *h)
{
        h->version = PIMFOR_VERSION;
        h->operation = operation;
        h->device_id = PIMFOR_DEV_ID_MHLI_MIB;
        h->flags = 0;
        h->oid = cpu_to_be32(oid);
        h->length = cpu_to_be32(length);
}

/*
 * Helper function to analyze a PIMFOR management frame header.
 */
static pimfor_header_t *
pimfor_decode_header(void *data, int len)
{
        pimfor_header_t *h = data;

        while ((void *) h < data + len) {
                if (h->flags & PIMFOR_FLAG_LITTLE_ENDIAN) {
                        le32_to_cpus(&h->oid);
                        le32_to_cpus(&h->length);
                } else {
                        be32_to_cpus(&h->oid);
                        be32_to_cpus(&h->length);
                }
                if (h->oid != OID_INL_TUNNEL)
                        return h;
                h++;
        }
        return NULL;
}

/*
 * Fill the receive queue for management frames with fresh buffers.
 */
int
islpci_mgmt_rx_fill(struct net_device *ndev)
{
        islpci_private *priv = netdev_priv(ndev);
        isl38xx_control_block *cb =     /* volatile not needed */
            (isl38xx_control_block *) priv->control_block;
        u32 curr = le32_to_cpu(cb->driver_curr_frag[ISL38XX_CB_RX_MGMTQ]);

#if VERBOSE > SHOW_ERROR_MESSAGES
        DEBUG(SHOW_FUNCTION_CALLS, "islpci_mgmt_rx_fill\n");
#endif

        while (curr - priv->index_mgmt_rx < ISL38XX_CB_MGMT_QSIZE) {
                u32 index = curr % ISL38XX_CB_MGMT_QSIZE;
                struct islpci_membuf *buf = &priv->mgmt_rx[index];
                isl38xx_fragment *frag = &cb->rx_data_mgmt[index];

                if (buf->mem == NULL) {
                        buf->mem = kmalloc(MGMT_FRAME_SIZE, GFP_ATOMIC);
                        if (!buf->mem)
                                return -ENOMEM;
                        buf->size = MGMT_FRAME_SIZE;
                }
                if (buf->pci_addr == 0) {
                        buf->pci_addr = dma_map_single(&priv->pdev->dev,
                                                       buf->mem,
                                                       MGMT_FRAME_SIZE,
                                                       DMA_FROM_DEVICE);
                        if (dma_mapping_error(&priv->pdev->dev, buf->pci_addr)) {
                                printk(KERN_WARNING
                                       "Failed to make memory DMA'able.\n");
                                return -ENOMEM;
                        }
                }

                /* be safe: always reset control block information */
                frag->size = cpu_to_le16(MGMT_FRAME_SIZE);
                frag->flags = 0;
                frag->address = cpu_to_le32(buf->pci_addr);
                curr++;

                /* The fragment address in the control block must have
                 * been written before announcing the frame buffer to
                 * device */
                wmb();
                cb->driver_curr_frag[ISL38XX_CB_RX_MGMTQ] = cpu_to_le32(curr);
        }
        return 0;
}

/*
 * Create and transmit a management frame using "operation" and "oid",
 * with arguments data/length.
 * We either return an error and free the frame, or we return 0 and
 * islpci_mgt_cleanup_transmit() frees the frame in the tx-done
 * interrupt.
 */
static int
islpci_mgt_transmit(struct net_device *ndev, int operation, unsigned long oid,
                    void *data, int length)
{
        islpci_private *priv = netdev_priv(ndev);
        isl38xx_control_block *cb =
            (isl38xx_control_block *) priv->control_block;
        void *p;
        int err = -EINVAL;
        unsigned long flags;
        isl38xx_fragment *frag;
        struct islpci_membuf buf;
        u32 curr_frag;
        int index;
        int frag_len = length + PIMFOR_HEADER_SIZE;

#if VERBOSE > SHOW_ERROR_MESSAGES
        DEBUG(SHOW_FUNCTION_CALLS, "islpci_mgt_transmit\n");
#endif

        if (frag_len > MGMT_FRAME_SIZE) {
                printk(KERN_DEBUG "%s: mgmt frame too large %d\n",
                       ndev->name, frag_len);
                goto error;
        }

        err = -ENOMEM;
        p = buf.mem = kmalloc(frag_len, GFP_KERNEL);
        if (!buf.mem)
                goto error;

        buf.size = frag_len;

        /* create the header directly in the fragment data area */
        pimfor_encode_header(operation, oid, length, (pimfor_header_t *) p);
        p += PIMFOR_HEADER_SIZE;

        if (data)
                memcpy(p, data, length);
        else
                memset(p, 0, length);

#if VERBOSE > SHOW_ERROR_MESSAGES
        {
                pimfor_header_t *h = buf.mem;
                DEBUG(SHOW_PIMFOR_FRAMES,
                      "PIMFOR: op %i, oid 0x%08lx, device %i, flags 0x%x length 0x%x\n",
                      h->operation, oid, h->device_id, h->flags, length);

                /* display the buffer contents for debugging */
                display_buffer((char *) h, sizeof (pimfor_header_t));
                display_buffer(p, length);
        }
#endif

        err = -ENOMEM;
        buf.pci_addr = dma_map_single(&priv->pdev->dev, buf.mem, frag_len,
                                      DMA_TO_DEVICE);
        if (dma_mapping_error(&priv->pdev->dev, buf.pci_addr)) {
                printk(KERN_WARNING "%s: cannot map PCI memory for mgmt\n",
                       ndev->name);
                goto error_free;
        }

        /* Protect the control block modifications against interrupts. */
        spin_lock_irqsave(&priv->slock, flags);
        curr_frag = le32_to_cpu(cb->driver_curr_frag[ISL38XX_CB_TX_MGMTQ]);
        if (curr_frag - priv->index_mgmt_tx >= ISL38XX_CB_MGMT_QSIZE) {
                printk(KERN_WARNING "%s: mgmt tx queue is still full\n",
                       ndev->name);
                goto error_unlock;
        }

        /* commit the frame to the tx device queue */
        index = curr_frag % ISL38XX_CB_MGMT_QSIZE;
        priv->mgmt_tx[index] = buf;
        frag = &cb->tx_data_mgmt[index];
        frag->size = cpu_to_le16(frag_len);
        frag->flags = 0;        /* for any other than the last fragment, set to 1 */
        frag->address = cpu_to_le32(buf.pci_addr);

        /* The fragment address in the control block must have
         * been written before announcing the frame buffer to
         * device */
        wmb();
        cb->driver_curr_frag[ISL38XX_CB_TX_MGMTQ] = cpu_to_le32(curr_frag + 1);
        spin_unlock_irqrestore(&priv->slock, flags);

        /* trigger the device */
        islpci_trigger(priv);
        return 0;

      error_unlock:
        spin_unlock_irqrestore(&priv->slock, flags);
      error_free:
        kfree(buf.mem);
      error:
        return err;
}

/*
 * Receive a management frame from the device.
 * This can be an arbitrary number of traps, and at most one response
 * frame for a previous request sent via islpci_mgt_transmit().
 */
int
islpci_mgt_receive(struct net_device *ndev)
{
        islpci_private *priv = netdev_priv(ndev);
        isl38xx_control_block *cb =
            (isl38xx_control_block *) priv->control_block;
        u32 curr_frag;

#if VERBOSE > SHOW_ERROR_MESSAGES
        DEBUG(SHOW_FUNCTION_CALLS, "islpci_mgt_receive\n");
#endif

        /* Only once per interrupt, determine fragment range to
         * process.  This avoids an endless loop (i.e. lockup) if
         * frames come in faster than we can process them. */
        curr_frag = le32_to_cpu(cb->device_curr_frag[ISL38XX_CB_RX_MGMTQ]);
        barrier();

        for (; priv->index_mgmt_rx < curr_frag; priv->index_mgmt_rx++) {
                pimfor_header_t *header;
                u32 index = priv->index_mgmt_rx % ISL38XX_CB_MGMT_QSIZE;
                struct islpci_membuf *buf = &priv->mgmt_rx[index];
                u16 frag_len;
                int size;
                struct islpci_mgmtframe *frame;

                /* I have no idea (and no documentation) if flags != 0
                 * is possible.  Drop the frame, reuse the buffer. */
                if (le16_to_cpu(cb->rx_data_mgmt[index].flags) != 0) {
                        printk(KERN_WARNING "%s: unknown flags 0x%04x\n",
                               ndev->name,
                               le16_to_cpu(cb->rx_data_mgmt[index].flags));
                        continue;
                }

                /* The device only returns the size of the header(s) here. */
                frag_len = le16_to_cpu(cb->rx_data_mgmt[index].size);

                /*
                 * We appear to have no way to tell the device the
                 * size of a receive buffer.  Thus, if this check
                 * triggers, we likely have kernel heap corruption. */
                if (frag_len > MGMT_FRAME_SIZE) {
                        printk(KERN_WARNING
                                "%s: Bogus packet size of %d (%#x).\n",
                                ndev->name, frag_len, frag_len);
                        frag_len = MGMT_FRAME_SIZE;
                }

                /* Ensure the results of device DMA are visible to the CPU. */
                dma_sync_single_for_cpu(&priv->pdev->dev, buf->pci_addr,
                                        buf->size, DMA_FROM_DEVICE);

                /* Perform endianess conversion for PIMFOR header in-place. */
                header = pimfor_decode_header(buf->mem, frag_len);
                if (!header) {
                        printk(KERN_WARNING "%s: no PIMFOR header found\n",
                               ndev->name);
                        continue;
                }

                /* The device ID from the PIMFOR packet received from
                 * the MVC is always 0.  We forward a sensible device_id.
                 * Not that anyone upstream would care... */
                header->device_id = priv->ndev->ifindex;

#if VERBOSE > SHOW_ERROR_MESSAGES
                DEBUG(SHOW_PIMFOR_FRAMES,
                      "PIMFOR: op %i, oid 0x%08x, device %i, flags 0x%x length 0x%x\n",
                      header->operation, header->oid, header->device_id,
                      header->flags, header->length);

                /* display the buffer contents for debugging */
                display_buffer((char *) header, PIMFOR_HEADER_SIZE);
                display_buffer((char *) header + PIMFOR_HEADER_SIZE,
                               header->length);
#endif

                /* nobody sends these */
                if (header->flags & PIMFOR_FLAG_APPLIC_ORIGIN) {
                        printk(KERN_DEBUG
                               "%s: errant PIMFOR application frame\n",
                               ndev->name);
                        continue;
                }

                /* Determine frame size, skipping OID_INL_TUNNEL headers. */
                size = PIMFOR_HEADER_SIZE + header->length;
                frame = kmalloc(sizeof(struct islpci_mgmtframe) + size,
                                GFP_ATOMIC);
                if (!frame)
                        continue;

                frame->ndev = ndev;
                memcpy(&frame->buf, header, size);
                frame->header = (pimfor_header_t *) frame->buf;
                frame->data = frame->buf + PIMFOR_HEADER_SIZE;

#if VERBOSE > SHOW_ERROR_MESSAGES
                DEBUG(SHOW_PIMFOR_FRAMES,
                      "frame: header: %p, data: %p, size: %d\n",
                      frame->header, frame->data, size);
#endif

                if (header->operation == PIMFOR_OP_TRAP) {
#if VERBOSE > SHOW_ERROR_MESSAGES
                        printk(KERN_DEBUG
                               "TRAP: oid 0x%x, device %i, flags 0x%x length %i\n",
                               header->oid, header->device_id, header->flags,
                               header->length);
#endif

                        /* Create work to handle trap out of interrupt
                         * context. */
                        INIT_WORK(&frame->ws, prism54_process_trap);
                        schedule_work(&frame->ws);

                } else {
                        /* Signal the one waiting process that a response
                         * has been received. */
                        if ((frame = xchg(&priv->mgmt_received, frame)) != NULL) {
                                printk(KERN_WARNING
                                       "%s: mgmt response not collected\n",
                                       ndev->name);
                                kfree(frame);
                        }
#if VERBOSE > SHOW_ERROR_MESSAGES
                        DEBUG(SHOW_TRACING, "Wake up Mgmt Queue\n");
#endif
                        wake_up(&priv->mgmt_wqueue);
                }

        }

        return 0;
}

/*
 * Cleanup the transmit queue by freeing all frames handled by the device.
 */
void
islpci_mgt_cleanup_transmit(struct net_device *ndev)
{
        islpci_private *priv = netdev_priv(ndev);
        isl38xx_control_block *cb =     /* volatile not needed */
            (isl38xx_control_block *) priv->control_block;
        u32 curr_frag;

#if VERBOSE > SHOW_ERROR_MESSAGES
        DEBUG(SHOW_FUNCTION_CALLS, "islpci_mgt_cleanup_transmit\n");
#endif

        /* Only once per cleanup, determine fragment range to
         * process.  This avoids an endless loop (i.e. lockup) if
         * the device became confused, incrementing device_curr_frag
         * rapidly. */
        curr_frag = le32_to_cpu(cb->device_curr_frag[ISL38XX_CB_TX_MGMTQ]);
        barrier();

        for (; priv->index_mgmt_tx < curr_frag; priv->index_mgmt_tx++) {
                int index = priv->index_mgmt_tx % ISL38XX_CB_MGMT_QSIZE;
                struct islpci_membuf *buf = &priv->mgmt_tx[index];
                dma_unmap_single(&priv->pdev->dev, buf->pci_addr, buf->size,
                                 DMA_TO_DEVICE);
                buf->pci_addr = 0;
                kfree(buf->mem);
                buf->mem = NULL;
                buf->size = 0;
        }
}

/*
 * Perform one request-response transaction to the device.
 */
int
islpci_mgt_transaction(struct net_device *ndev,
                       int operation, unsigned long oid,
                       void *senddata, int sendlen,
                       struct islpci_mgmtframe **recvframe)
{
        islpci_private *priv = netdev_priv(ndev);
        const long wait_cycle_jiffies = msecs_to_jiffies(ISL38XX_WAIT_CYCLE * 10);
        long timeout_left = ISL38XX_MAX_WAIT_CYCLES * wait_cycle_jiffies;
        int err;
        DEFINE_WAIT(wait);

        *recvframe = NULL;

        if (mutex_lock_interruptible(&priv->mgmt_lock))
                return -ERESTARTSYS;

        prepare_to_wait(&priv->mgmt_wqueue, &wait, TASK_UNINTERRUPTIBLE);
        err = islpci_mgt_transmit(ndev, operation, oid, senddata, sendlen);
        if (err)
                goto out;

        err = -ETIMEDOUT;
        while (timeout_left > 0) {
                int timeleft;
                struct islpci_mgmtframe *frame;

                timeleft = schedule_timeout_uninterruptible(wait_cycle_jiffies);
                frame = xchg(&priv->mgmt_received, NULL);
                if (frame) {
                        if (frame->header->oid == oid) {
                                *recvframe = frame;
                                err = 0;
                                goto out;
                        } else {
                                printk(KERN_DEBUG
                                       "%s: expecting oid 0x%x, received 0x%x.\n",
                                       ndev->name, (unsigned int) oid,
                                       frame->header->oid);
                                kfree(frame);
                                frame = NULL;
                        }
                }
                if (timeleft == 0) {
                        printk(KERN_DEBUG
                                "%s: timeout waiting for mgmt response %lu, "
                                "triggering device\n",
                                ndev->name, timeout_left);
                        islpci_trigger(priv);
                }
                timeout_left += timeleft - wait_cycle_jiffies;
        }
        printk(KERN_WARNING "%s: timeout waiting for mgmt response\n",
               ndev->name);

        /* TODO: we should reset the device here */
 out:
        finish_wait(&priv->mgmt_wqueue, &wait);
        mutex_unlock(&priv->mgmt_lock);
        return err;
}