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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/atm/ambassador.c
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.bz2
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/atm/ambassador.c')
-rw-r--r--drivers/atm/ambassador.c2463
1 files changed, 2463 insertions, 0 deletions
diff --git a/drivers/atm/ambassador.c b/drivers/atm/ambassador.c
new file mode 100644
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+++ b/drivers/atm/ambassador.c
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+/*
+ Madge Ambassador ATM Adapter driver.
+ Copyright (C) 1995-1999 Madge Networks Ltd.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+ The GNU GPL is contained in /usr/doc/copyright/GPL on a Debian
+ system and in the file COPYING in the Linux kernel source.
+*/
+
+/* * dedicated to the memory of Graham Gordon 1971-1998 * */
+
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/pci.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/atmdev.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+
+#include <asm/atomic.h>
+#include <asm/io.h>
+#include <asm/byteorder.h>
+
+#include "ambassador.h"
+
+#define maintainer_string "Giuliano Procida at Madge Networks <gprocida@madge.com>"
+#define description_string "Madge ATM Ambassador driver"
+#define version_string "1.2.4"
+
+static inline void __init show_version (void) {
+ printk ("%s version %s\n", description_string, version_string);
+}
+
+/*
+
+ Theory of Operation
+
+ I Hardware, detection, initialisation and shutdown.
+
+ 1. Supported Hardware
+
+ This driver is for the PCI ATMizer-based Ambassador card (except
+ very early versions). It is not suitable for the similar EISA "TR7"
+ card. Commercially, both cards are known as Collage Server ATM
+ adapters.
+
+ The loader supports image transfer to the card, image start and few
+ other miscellaneous commands.
+
+ Only AAL5 is supported with vpi = 0 and vci in the range 0 to 1023.
+
+ The cards are big-endian.
+
+ 2. Detection
+
+ Standard PCI stuff, the early cards are detected and rejected.
+
+ 3. Initialisation
+
+ The cards are reset and the self-test results are checked. The
+ microcode image is then transferred and started. This waits for a
+ pointer to a descriptor containing details of the host-based queues
+ and buffers and various parameters etc. Once they are processed
+ normal operations may begin. The BIA is read using a microcode
+ command.
+
+ 4. Shutdown
+
+ This may be accomplished either by a card reset or via the microcode
+ shutdown command. Further investigation required.
+
+ 5. Persistent state
+
+ The card reset does not affect PCI configuration (good) or the
+ contents of several other "shared run-time registers" (bad) which
+ include doorbell and interrupt control as well as EEPROM and PCI
+ control. The driver must be careful when modifying these registers
+ not to touch bits it does not use and to undo any changes at exit.
+
+ II Driver software
+
+ 0. Generalities
+
+ The adapter is quite intelligent (fast) and has a simple interface
+ (few features). VPI is always zero, 1024 VCIs are supported. There
+ is limited cell rate support. UBR channels can be capped and ABR
+ (explicit rate, but not EFCI) is supported. There is no CBR or VBR
+ support.
+
+ 1. Driver <-> Adapter Communication
+
+ Apart from the basic loader commands, the driver communicates
+ through three entities: the command queue (CQ), the transmit queue
+ pair (TXQ) and the receive queue pairs (RXQ). These three entities
+ are set up by the host and passed to the microcode just after it has
+ been started.
+
+ All queues are host-based circular queues. They are contiguous and
+ (due to hardware limitations) have some restrictions as to their
+ locations in (bus) memory. They are of the "full means the same as
+ empty so don't do that" variety since the adapter uses pointers
+ internally.
+
+ The queue pairs work as follows: one queue is for supply to the
+ adapter, items in it are pending and are owned by the adapter; the
+ other is the queue for return from the adapter, items in it have
+ been dealt with by the adapter. The host adds items to the supply
+ (TX descriptors and free RX buffer descriptors) and removes items
+ from the return (TX and RX completions). The adapter deals with out
+ of order completions.
+
+ Interrupts (card to host) and the doorbell (host to card) are used
+ for signalling.
+
+ 1. CQ
+
+ This is to communicate "open VC", "close VC", "get stats" etc. to
+ the adapter. At most one command is retired every millisecond by the
+ card. There is no out of order completion or notification. The
+ driver needs to check the return code of the command, waiting as
+ appropriate.
+
+ 2. TXQ
+
+ TX supply items are of variable length (scatter gather support) and
+ so the queue items are (more or less) pointers to the real thing.
+ Each TX supply item contains a unique, host-supplied handle (the skb
+ bus address seems most sensible as this works for Alphas as well,
+ there is no need to do any endian conversions on the handles).
+
+ TX return items consist of just the handles above.
+
+ 3. RXQ (up to 4 of these with different lengths and buffer sizes)
+
+ RX supply items consist of a unique, host-supplied handle (the skb
+ bus address again) and a pointer to the buffer data area.
+
+ RX return items consist of the handle above, the VC, length and a
+ status word. This just screams "oh so easy" doesn't it?
+
+ Note on RX pool sizes:
+
+ Each pool should have enough buffers to handle a back-to-back stream
+ of minimum sized frames on a single VC. For example:
+
+ frame spacing = 3us (about right)
+
+ delay = IRQ lat + RX handling + RX buffer replenish = 20 (us) (a guess)
+
+ min number of buffers for one VC = 1 + delay/spacing (buffers)
+
+ delay/spacing = latency = (20+2)/3 = 7 (buffers) (rounding up)
+
+ The 20us delay assumes that there is no need to sleep; if we need to
+ sleep to get buffers we are going to drop frames anyway.
+
+ In fact, each pool should have enough buffers to support the
+ simultaneous reassembly of a separate frame on each VC and cope with
+ the case in which frames complete in round robin cell fashion on
+ each VC.
+
+ Only one frame can complete at each cell arrival, so if "n" VCs are
+ open, the worst case is to have them all complete frames together
+ followed by all starting new frames together.
+
+ desired number of buffers = n + delay/spacing
+
+ These are the extreme requirements, however, they are "n+k" for some
+ "k" so we have only the constant to choose. This is the argument
+ rx_lats which current defaults to 7.
+
+ Actually, "n ? n+k : 0" is better and this is what is implemented,
+ subject to the limit given by the pool size.
+
+ 4. Driver locking
+
+ Simple spinlocks are used around the TX and RX queue mechanisms.
+ Anyone with a faster, working method is welcome to implement it.
+
+ The adapter command queue is protected with a spinlock. We always
+ wait for commands to complete.
+
+ A more complex form of locking is used around parts of the VC open
+ and close functions. There are three reasons for a lock: 1. we need
+ to do atomic rate reservation and release (not used yet), 2. Opening
+ sometimes involves two adapter commands which must not be separated
+ by another command on the same VC, 3. the changes to RX pool size
+ must be atomic. The lock needs to work over context switches, so we
+ use a semaphore.
+
+ III Hardware Features and Microcode Bugs
+
+ 1. Byte Ordering
+
+ *%^"$&%^$*&^"$(%^$#&^%$(&#%$*(&^#%!"!"!*!
+
+ 2. Memory access
+
+ All structures that are not accessed using DMA must be 4-byte
+ aligned (not a problem) and must not cross 4MB boundaries.
+
+ There is a DMA memory hole at E0000000-E00000FF (groan).
+
+ TX fragments (DMA read) must not cross 4MB boundaries (would be 16MB
+ but for a hardware bug).
+
+ RX buffers (DMA write) must not cross 16MB boundaries and must
+ include spare trailing bytes up to the next 4-byte boundary; they
+ will be written with rubbish.
+
+ The PLX likes to prefetch; if reading up to 4 u32 past the end of
+ each TX fragment is not a problem, then TX can be made to go a
+ little faster by passing a flag at init that disables a prefetch
+ workaround. We do not pass this flag. (new microcode only)
+
+ Now we:
+ . Note that alloc_skb rounds up size to a 16byte boundary.
+ . Ensure all areas do not traverse 4MB boundaries.
+ . Ensure all areas do not start at a E00000xx bus address.
+ (I cannot be certain, but this may always hold with Linux)
+ . Make all failures cause a loud message.
+ . Discard non-conforming SKBs (causes TX failure or RX fill delay).
+ . Discard non-conforming TX fragment descriptors (the TX fails).
+ In the future we could:
+ . Allow RX areas that traverse 4MB (but not 16MB) boundaries.
+ . Segment TX areas into some/more fragments, when necessary.
+ . Relax checks for non-DMA items (ignore hole).
+ . Give scatter-gather (iovec) requirements using ???. (?)
+
+ 3. VC close is broken (only for new microcode)
+
+ The VC close adapter microcode command fails to do anything if any
+ frames have been received on the VC but none have been transmitted.
+ Frames continue to be reassembled and passed (with IRQ) to the
+ driver.
+
+ IV To Do List
+
+ . Fix bugs!
+
+ . Timer code may be broken.
+
+ . Deal with buggy VC close (somehow) in microcode 12.
+
+ . Handle interrupted and/or non-blocking writes - is this a job for
+ the protocol layer?
+
+ . Add code to break up TX fragments when they span 4MB boundaries.
+
+ . Add SUNI phy layer (need to know where SUNI lives on card).
+
+ . Implement a tx_alloc fn to (a) satisfy TX alignment etc. and (b)
+ leave extra headroom space for Ambassador TX descriptors.
+
+ . Understand these elements of struct atm_vcc: recvq (proto?),
+ sleep, callback, listenq, backlog_quota, reply and user_back.
+
+ . Adjust TX/RX skb allocation to favour IP with LANE/CLIP (configurable).
+
+ . Impose a TX-pending limit (2?) on each VC, help avoid TX q overflow.
+
+ . Decide whether RX buffer recycling is or can be made completely safe;
+ turn it back on. It looks like Werner is going to axe this.
+
+ . Implement QoS changes on open VCs (involves extracting parts of VC open
+ and close into separate functions and using them to make changes).
+
+ . Hack on command queue so that someone can issue multiple commands and wait
+ on the last one (OR only "no-op" or "wait" commands are waited for).
+
+ . Eliminate need for while-schedule around do_command.
+
+*/
+
+/********** microcode **********/
+
+#ifdef AMB_NEW_MICROCODE
+#define UCODE(x) UCODE2(atmsar12.x)
+#else
+#define UCODE(x) UCODE2(atmsar11.x)
+#endif
+#define UCODE2(x) #x
+
+static u32 __devinitdata ucode_start =
+#include UCODE(start)
+;
+
+static region __devinitdata ucode_regions[] = {
+#include UCODE(regions)
+ { 0, 0 }
+};
+
+static u32 __devinitdata ucode_data[] = {
+#include UCODE(data)
+ 0xdeadbeef
+};
+
+static void do_housekeeping (unsigned long arg);
+/********** globals **********/
+
+static unsigned short debug = 0;
+static unsigned int cmds = 8;
+static unsigned int txs = 32;
+static unsigned int rxs[NUM_RX_POOLS] = { 64, 64, 64, 64 };
+static unsigned int rxs_bs[NUM_RX_POOLS] = { 4080, 12240, 36720, 65535 };
+static unsigned int rx_lats = 7;
+static unsigned char pci_lat = 0;
+
+static const unsigned long onegigmask = -1 << 30;
+
+/********** access to adapter **********/
+
+static inline void wr_plain (const amb_dev * dev, size_t addr, u32 data) {
+ PRINTD (DBG_FLOW|DBG_REGS, "wr: %08zx <- %08x", addr, data);
+#ifdef AMB_MMIO
+ dev->membase[addr / sizeof(u32)] = data;
+#else
+ outl (data, dev->iobase + addr);
+#endif
+}
+
+static inline u32 rd_plain (const amb_dev * dev, size_t addr) {
+#ifdef AMB_MMIO
+ u32 data = dev->membase[addr / sizeof(u32)];
+#else
+ u32 data = inl (dev->iobase + addr);
+#endif
+ PRINTD (DBG_FLOW|DBG_REGS, "rd: %08zx -> %08x", addr, data);
+ return data;
+}
+
+static inline void wr_mem (const amb_dev * dev, size_t addr, u32 data) {
+ __be32 be = cpu_to_be32 (data);
+ PRINTD (DBG_FLOW|DBG_REGS, "wr: %08zx <- %08x b[%08x]", addr, data, be);
+#ifdef AMB_MMIO
+ dev->membase[addr / sizeof(u32)] = be;
+#else
+ outl (be, dev->iobase + addr);
+#endif
+}
+
+static inline u32 rd_mem (const amb_dev * dev, size_t addr) {
+#ifdef AMB_MMIO
+ __be32 be = dev->membase[addr / sizeof(u32)];
+#else
+ __be32 be = inl (dev->iobase + addr);
+#endif
+ u32 data = be32_to_cpu (be);
+ PRINTD (DBG_FLOW|DBG_REGS, "rd: %08zx -> %08x b[%08x]", addr, data, be);
+ return data;
+}
+
+/********** dump routines **********/
+
+static inline void dump_registers (const amb_dev * dev) {
+#ifdef DEBUG_AMBASSADOR
+ if (debug & DBG_REGS) {
+ size_t i;
+ PRINTD (DBG_REGS, "reading PLX control: ");
+ for (i = 0x00; i < 0x30; i += sizeof(u32))
+ rd_mem (dev, i);
+ PRINTD (DBG_REGS, "reading mailboxes: ");
+ for (i = 0x40; i < 0x60; i += sizeof(u32))
+ rd_mem (dev, i);
+ PRINTD (DBG_REGS, "reading doorb irqev irqen reset:");
+ for (i = 0x60; i < 0x70; i += sizeof(u32))
+ rd_mem (dev, i);
+ }
+#else
+ (void) dev;
+#endif
+ return;
+}
+
+static inline void dump_loader_block (volatile loader_block * lb) {
+#ifdef DEBUG_AMBASSADOR
+ unsigned int i;
+ PRINTDB (DBG_LOAD, "lb @ %p; res: %d, cmd: %d, pay:",
+ lb, be32_to_cpu (lb->result), be32_to_cpu (lb->command));
+ for (i = 0; i < MAX_COMMAND_DATA; ++i)
+ PRINTDM (DBG_LOAD, " %08x", be32_to_cpu (lb->payload.data[i]));
+ PRINTDE (DBG_LOAD, ", vld: %08x", be32_to_cpu (lb->valid));
+#else
+ (void) lb;
+#endif
+ return;
+}
+
+static inline void dump_command (command * cmd) {
+#ifdef DEBUG_AMBASSADOR
+ unsigned int i;
+ PRINTDB (DBG_CMD, "cmd @ %p, req: %08x, pars:",
+ cmd, /*be32_to_cpu*/ (cmd->request));
+ for (i = 0; i < 3; ++i)
+ PRINTDM (DBG_CMD, " %08x", /*be32_to_cpu*/ (cmd->args.par[i]));
+ PRINTDE (DBG_CMD, "");
+#else
+ (void) cmd;
+#endif
+ return;
+}
+
+static inline void dump_skb (char * prefix, unsigned int vc, struct sk_buff * skb) {
+#ifdef DEBUG_AMBASSADOR
+ unsigned int i;
+ unsigned char * data = skb->data;
+ PRINTDB (DBG_DATA, "%s(%u) ", prefix, vc);
+ for (i=0; i<skb->len && i < 256;i++)
+ PRINTDM (DBG_DATA, "%02x ", data[i]);
+ PRINTDE (DBG_DATA,"");
+#else
+ (void) prefix;
+ (void) vc;
+ (void) skb;
+#endif
+ return;
+}
+
+/********** check memory areas for use by Ambassador **********/
+
+/* see limitations under Hardware Features */
+
+static inline int check_area (void * start, size_t length) {
+ // assumes length > 0
+ const u32 fourmegmask = -1 << 22;
+ const u32 twofivesixmask = -1 << 8;
+ const u32 starthole = 0xE0000000;
+ u32 startaddress = virt_to_bus (start);
+ u32 lastaddress = startaddress+length-1;
+ if ((startaddress ^ lastaddress) & fourmegmask ||
+ (startaddress & twofivesixmask) == starthole) {
+ PRINTK (KERN_ERR, "check_area failure: [%x,%x] - mail maintainer!",
+ startaddress, lastaddress);
+ return -1;
+ } else {
+ return 0;
+ }
+}
+
+/********** free an skb (as per ATM device driver documentation) **********/
+
+static inline void amb_kfree_skb (struct sk_buff * skb) {
+ if (ATM_SKB(skb)->vcc->pop) {
+ ATM_SKB(skb)->vcc->pop (ATM_SKB(skb)->vcc, skb);
+ } else {
+ dev_kfree_skb_any (skb);
+ }
+}
+
+/********** TX completion **********/
+
+static inline void tx_complete (amb_dev * dev, tx_out * tx) {
+ tx_simple * tx_descr = bus_to_virt (tx->handle);
+ struct sk_buff * skb = tx_descr->skb;
+
+ PRINTD (DBG_FLOW|DBG_TX, "tx_complete %p %p", dev, tx);
+
+ // VC layer stats
+ atomic_inc(&ATM_SKB(skb)->vcc->stats->tx);
+
+ // free the descriptor
+ kfree (tx_descr);
+
+ // free the skb
+ amb_kfree_skb (skb);
+
+ dev->stats.tx_ok++;
+ return;
+}
+
+/********** RX completion **********/
+
+static void rx_complete (amb_dev * dev, rx_out * rx) {
+ struct sk_buff * skb = bus_to_virt (rx->handle);
+ u16 vc = be16_to_cpu (rx->vc);
+ // unused: u16 lec_id = be16_to_cpu (rx->lec_id);
+ u16 status = be16_to_cpu (rx->status);
+ u16 rx_len = be16_to_cpu (rx->length);
+
+ PRINTD (DBG_FLOW|DBG_RX, "rx_complete %p %p (len=%hu)", dev, rx, rx_len);
+
+ // XXX move this in and add to VC stats ???
+ if (!status) {
+ struct atm_vcc * atm_vcc = dev->rxer[vc];
+ dev->stats.rx.ok++;
+
+ if (atm_vcc) {
+
+ if (rx_len <= atm_vcc->qos.rxtp.max_sdu) {
+
+ if (atm_charge (atm_vcc, skb->truesize)) {
+
+ // prepare socket buffer
+ ATM_SKB(skb)->vcc = atm_vcc;
+ skb_put (skb, rx_len);
+
+ dump_skb ("<<<", vc, skb);
+
+ // VC layer stats
+ atomic_inc(&atm_vcc->stats->rx);
+ do_gettimeofday(&skb->stamp);
+ // end of our responsability
+ atm_vcc->push (atm_vcc, skb);
+ return;
+
+ } else {
+ // someone fix this (message), please!
+ PRINTD (DBG_INFO|DBG_RX, "dropped thanks to atm_charge (vc %hu, truesize %u)", vc, skb->truesize);
+ // drop stats incremented in atm_charge
+ }
+
+ } else {
+ PRINTK (KERN_INFO, "dropped over-size frame");
+ // should we count this?
+ atomic_inc(&atm_vcc->stats->rx_drop);
+ }
+
+ } else {
+ PRINTD (DBG_WARN|DBG_RX, "got frame but RX closed for channel %hu", vc);
+ // this is an adapter bug, only in new version of microcode
+ }
+
+ } else {
+ dev->stats.rx.error++;
+ if (status & CRC_ERR)
+ dev->stats.rx.badcrc++;
+ if (status & LEN_ERR)
+ dev->stats.rx.toolong++;
+ if (status & ABORT_ERR)
+ dev->stats.rx.aborted++;
+ if (status & UNUSED_ERR)
+ dev->stats.rx.unused++;
+ }
+
+ dev_kfree_skb_any (skb);
+ return;
+}
+
+/*
+
+ Note on queue handling.
+
+ Here "give" and "take" refer to queue entries and a queue (pair)
+ rather than frames to or from the host or adapter. Empty frame
+ buffers are given to the RX queue pair and returned unused or
+ containing RX frames. TX frames (well, pointers to TX fragment
+ lists) are given to the TX queue pair, completions are returned.
+
+*/
+
+/********** command queue **********/
+
+// I really don't like this, but it's the best I can do at the moment
+
+// also, the callers are responsible for byte order as the microcode
+// sometimes does 16-bit accesses (yuk yuk yuk)
+
+static int command_do (amb_dev * dev, command * cmd) {
+ amb_cq * cq = &dev->cq;
+ volatile amb_cq_ptrs * ptrs = &cq->ptrs;
+ command * my_slot;
+
+ PRINTD (DBG_FLOW|DBG_CMD, "command_do %p", dev);
+
+ if (test_bit (dead, &dev->flags))
+ return 0;
+
+ spin_lock (&cq->lock);
+
+ // if not full...
+ if (cq->pending < cq->maximum) {
+ // remember my slot for later
+ my_slot = ptrs->in;
+ PRINTD (DBG_CMD, "command in slot %p", my_slot);
+
+ dump_command (cmd);
+
+ // copy command in
+ *ptrs->in = *cmd;
+ cq->pending++;
+ ptrs->in = NEXTQ (ptrs->in, ptrs->start, ptrs->limit);
+
+ // mail the command
+ wr_mem (dev, offsetof(amb_mem, mb.adapter.cmd_address), virt_to_bus (ptrs->in));
+
+ if (cq->pending > cq->high)
+ cq->high = cq->pending;
+ spin_unlock (&cq->lock);
+
+ // these comments were in a while-loop before, msleep removes the loop
+ // go to sleep
+ // PRINTD (DBG_CMD, "wait: sleeping %lu for command", timeout);
+ msleep(cq->pending);
+
+ // wait for my slot to be reached (all waiters are here or above, until...)
+ while (ptrs->out != my_slot) {
+ PRINTD (DBG_CMD, "wait: command slot (now at %p)", ptrs->out);
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ schedule();
+ }
+
+ // wait on my slot (... one gets to its slot, and... )
+ while (ptrs->out->request != cpu_to_be32 (SRB_COMPLETE)) {
+ PRINTD (DBG_CMD, "wait: command slot completion");
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ schedule();
+ }
+
+ PRINTD (DBG_CMD, "command complete");
+ // update queue (... moves the queue along to the next slot)
+ spin_lock (&cq->lock);
+ cq->pending--;
+ // copy command out
+ *cmd = *ptrs->out;
+ ptrs->out = NEXTQ (ptrs->out, ptrs->start, ptrs->limit);
+ spin_unlock (&cq->lock);
+
+ return 0;
+ } else {
+ cq->filled++;
+ spin_unlock (&cq->lock);
+ return -EAGAIN;
+ }
+
+}
+
+/********** TX queue pair **********/
+
+static inline int tx_give (amb_dev * dev, tx_in * tx) {
+ amb_txq * txq = &dev->txq;
+ unsigned long flags;
+
+ PRINTD (DBG_FLOW|DBG_TX, "tx_give %p", dev);
+
+ if (test_bit (dead, &dev->flags))
+ return 0;
+
+ spin_lock_irqsave (&txq->lock, flags);
+
+ if (txq->pending < txq->maximum) {
+ PRINTD (DBG_TX, "TX in slot %p", txq->in.ptr);
+
+ *txq->in.ptr = *tx;
+ txq->pending++;
+ txq->in.ptr = NEXTQ (txq->in.ptr, txq->in.start, txq->in.limit);
+ // hand over the TX and ring the bell
+ wr_mem (dev, offsetof(amb_mem, mb.adapter.tx_address), virt_to_bus (txq->in.ptr));
+ wr_mem (dev, offsetof(amb_mem, doorbell), TX_FRAME);
+
+ if (txq->pending > txq->high)
+ txq->high = txq->pending;
+ spin_unlock_irqrestore (&txq->lock, flags);
+ return 0;
+ } else {
+ txq->filled++;
+ spin_unlock_irqrestore (&txq->lock, flags);
+ return -EAGAIN;
+ }
+}
+
+static inline int tx_take (amb_dev * dev) {
+ amb_txq * txq = &dev->txq;
+ unsigned long flags;
+
+ PRINTD (DBG_FLOW|DBG_TX, "tx_take %p", dev);
+
+ spin_lock_irqsave (&txq->lock, flags);
+
+ if (txq->pending && txq->out.ptr->handle) {
+ // deal with TX completion
+ tx_complete (dev, txq->out.ptr);
+ // mark unused again
+ txq->out.ptr->handle = 0;
+ // remove item
+ txq->pending--;
+ txq->out.ptr = NEXTQ (txq->out.ptr, txq->out.start, txq->out.limit);
+
+ spin_unlock_irqrestore (&txq->lock, flags);
+ return 0;
+ } else {
+
+ spin_unlock_irqrestore (&txq->lock, flags);
+ return -1;
+ }
+}
+
+/********** RX queue pairs **********/
+
+static inline int rx_give (amb_dev * dev, rx_in * rx, unsigned char pool) {
+ amb_rxq * rxq = &dev->rxq[pool];
+ unsigned long flags;
+
+ PRINTD (DBG_FLOW|DBG_RX, "rx_give %p[%hu]", dev, pool);
+
+ spin_lock_irqsave (&rxq->lock, flags);
+
+ if (rxq->pending < rxq->maximum) {
+ PRINTD (DBG_RX, "RX in slot %p", rxq->in.ptr);
+
+ *rxq->in.ptr = *rx;
+ rxq->pending++;
+ rxq->in.ptr = NEXTQ (rxq->in.ptr, rxq->in.start, rxq->in.limit);
+ // hand over the RX buffer
+ wr_mem (dev, offsetof(amb_mem, mb.adapter.rx_address[pool]), virt_to_bus (rxq->in.ptr));
+
+ spin_unlock_irqrestore (&rxq->lock, flags);
+ return 0;
+ } else {
+ spin_unlock_irqrestore (&rxq->lock, flags);
+ return -1;
+ }
+}
+
+static inline int rx_take (amb_dev * dev, unsigned char pool) {
+ amb_rxq * rxq = &dev->rxq[pool];
+ unsigned long flags;
+
+ PRINTD (DBG_FLOW|DBG_RX, "rx_take %p[%hu]", dev, pool);
+
+ spin_lock_irqsave (&rxq->lock, flags);
+
+ if (rxq->pending && (rxq->out.ptr->status || rxq->out.ptr->length)) {
+ // deal with RX completion
+ rx_complete (dev, rxq->out.ptr);
+ // mark unused again
+ rxq->out.ptr->status = 0;
+ rxq->out.ptr->length = 0;
+ // remove item
+ rxq->pending--;
+ rxq->out.ptr = NEXTQ (rxq->out.ptr, rxq->out.start, rxq->out.limit);
+
+ if (rxq->pending < rxq->low)
+ rxq->low = rxq->pending;
+ spin_unlock_irqrestore (&rxq->lock, flags);
+ return 0;
+ } else {
+ if (!rxq->pending && rxq->buffers_wanted)
+ rxq->emptied++;
+ spin_unlock_irqrestore (&rxq->lock, flags);
+ return -1;
+ }
+}
+
+/********** RX Pool handling **********/
+
+/* pre: buffers_wanted = 0, post: pending = 0 */
+static inline void drain_rx_pool (amb_dev * dev, unsigned char pool) {
+ amb_rxq * rxq = &dev->rxq[pool];
+
+ PRINTD (DBG_FLOW|DBG_POOL, "drain_rx_pool %p %hu", dev, pool);
+
+ if (test_bit (dead, &dev->flags))
+ return;
+
+ /* we are not quite like the fill pool routines as we cannot just
+ remove one buffer, we have to remove all of them, but we might as
+ well pretend... */
+ if (rxq->pending > rxq->buffers_wanted) {
+ command cmd;
+ cmd.request = cpu_to_be32 (SRB_FLUSH_BUFFER_Q);
+ cmd.args.flush.flags = cpu_to_be32 (pool << SRB_POOL_SHIFT);
+ while (command_do (dev, &cmd))
+ schedule();
+ /* the pool may also be emptied via the interrupt handler */
+ while (rxq->pending > rxq->buffers_wanted)
+ if (rx_take (dev, pool))
+ schedule();
+ }
+
+ return;
+}
+
+static void drain_rx_pools (amb_dev * dev) {
+ unsigned char pool;
+
+ PRINTD (DBG_FLOW|DBG_POOL, "drain_rx_pools %p", dev);
+
+ for (pool = 0; pool < NUM_RX_POOLS; ++pool)
+ drain_rx_pool (dev, pool);
+}
+
+static inline void fill_rx_pool (amb_dev * dev, unsigned char pool, int priority) {
+ rx_in rx;
+ amb_rxq * rxq;
+
+ PRINTD (DBG_FLOW|DBG_POOL, "fill_rx_pool %p %hu %x", dev, pool, priority);
+
+ if (test_bit (dead, &dev->flags))
+ return;
+
+ rxq = &dev->rxq[pool];
+ while (rxq->pending < rxq->maximum && rxq->pending < rxq->buffers_wanted) {
+
+ struct sk_buff * skb = alloc_skb (rxq->buffer_size, priority);
+ if (!skb) {
+ PRINTD (DBG_SKB|DBG_POOL, "failed to allocate skb for RX pool %hu", pool);
+ return;
+ }
+ if (check_area (skb->data, skb->truesize)) {
+ dev_kfree_skb_any (skb);
+ return;
+ }
+ // cast needed as there is no %? for pointer differences
+ PRINTD (DBG_SKB, "allocated skb at %p, head %p, area %li",
+ skb, skb->head, (long) (skb->end - skb->head));
+ rx.handle = virt_to_bus (skb);
+ rx.host_address = cpu_to_be32 (virt_to_bus (skb->data));
+ if (rx_give (dev, &rx, pool))
+ dev_kfree_skb_any (skb);
+
+ }
+
+ return;
+}
+
+// top up all RX pools (can also be called as a bottom half)
+static void fill_rx_pools (amb_dev * dev) {
+ unsigned char pool;
+
+ PRINTD (DBG_FLOW|DBG_POOL, "fill_rx_pools %p", dev);
+
+ for (pool = 0; pool < NUM_RX_POOLS; ++pool)
+ fill_rx_pool (dev, pool, GFP_ATOMIC);
+
+ return;
+}
+
+/********** enable host interrupts **********/
+
+static inline void interrupts_on (amb_dev * dev) {
+ wr_plain (dev, offsetof(amb_mem, interrupt_control),
+ rd_plain (dev, offsetof(amb_mem, interrupt_control))
+ | AMB_INTERRUPT_BITS);
+}
+
+/********** disable host interrupts **********/
+
+static inline void interrupts_off (amb_dev * dev) {
+ wr_plain (dev, offsetof(amb_mem, interrupt_control),
+ rd_plain (dev, offsetof(amb_mem, interrupt_control))
+ &~ AMB_INTERRUPT_BITS);
+}
+
+/********** interrupt handling **********/
+
+static irqreturn_t interrupt_handler(int irq, void *dev_id,
+ struct pt_regs *pt_regs) {
+ amb_dev * dev = (amb_dev *) dev_id;
+ (void) pt_regs;
+
+ PRINTD (DBG_IRQ|DBG_FLOW, "interrupt_handler: %p", dev_id);
+
+ if (!dev_id) {
+ PRINTD (DBG_IRQ|DBG_ERR, "irq with NULL dev_id: %d", irq);
+ return IRQ_NONE;
+ }
+
+ {
+ u32 interrupt = rd_plain (dev, offsetof(amb_mem, interrupt));
+
+ // for us or someone else sharing the same interrupt
+ if (!interrupt) {
+ PRINTD (DBG_IRQ, "irq not for me: %d", irq);
+ return IRQ_NONE;
+ }
+
+ // definitely for us
+ PRINTD (DBG_IRQ, "FYI: interrupt was %08x", interrupt);
+ wr_plain (dev, offsetof(amb_mem, interrupt), -1);
+ }
+
+ {
+ unsigned int irq_work = 0;
+ unsigned char pool;
+ for (pool = 0; pool < NUM_RX_POOLS; ++pool)
+ while (!rx_take (dev, pool))
+ ++irq_work;
+ while (!tx_take (dev))
+ ++irq_work;
+
+ if (irq_work) {
+#ifdef FILL_RX_POOLS_IN_BH
+ schedule_work (&dev->bh);
+#else
+ fill_rx_pools (dev);
+#endif
+
+ PRINTD (DBG_IRQ, "work done: %u", irq_work);
+ } else {
+ PRINTD (DBG_IRQ|DBG_WARN, "no work done");
+ }
+ }
+
+ PRINTD (DBG_IRQ|DBG_FLOW, "interrupt_handler done: %p", dev_id);
+ return IRQ_HANDLED;
+}
+
+/********** make rate (not quite as much fun as Horizon) **********/
+
+static unsigned int make_rate (unsigned int rate, rounding r,
+ u16 * bits, unsigned int * actual) {
+ unsigned char exp = -1; // hush gcc
+ unsigned int man = -1; // hush gcc
+
+ PRINTD (DBG_FLOW|DBG_QOS, "make_rate %u", rate);
+
+ // rates in cells per second, ITU format (nasty 16-bit floating-point)
+ // given 5-bit e and 9-bit m:
+ // rate = EITHER (1+m/2^9)*2^e OR 0
+ // bits = EITHER 1<<14 | e<<9 | m OR 0
+ // (bit 15 is "reserved", bit 14 "non-zero")
+ // smallest rate is 0 (special representation)
+ // largest rate is (1+511/512)*2^31 = 4290772992 (< 2^32-1)
+ // smallest non-zero rate is (1+0/512)*2^0 = 1 (> 0)
+ // simple algorithm:
+ // find position of top bit, this gives e
+ // remove top bit and shift (rounding if feeling clever) by 9-e
+
+ // ucode bug: please don't set bit 14! so 0 rate not representable
+
+ if (rate > 0xffc00000U) {
+ // larger than largest representable rate
+
+ if (r == round_up) {
+ return -EINVAL;
+ } else {
+ exp = 31;
+ man = 511;
+ }
+
+ } else if (rate) {
+ // representable rate
+
+ exp = 31;
+ man = rate;
+
+ // invariant: rate = man*2^(exp-31)
+ while (!(man & (1<<31))) {
+ exp = exp - 1;
+ man = man<<1;
+ }
+
+ // man has top bit set
+ // rate = (2^31+(man-2^31))*2^(exp-31)
+ // rate = (1+(man-2^31)/2^31)*2^exp
+ man = man<<1;
+ man &= 0xffffffffU; // a nop on 32-bit systems
+ // rate = (1+man/2^32)*2^exp
+
+ // exp is in the range 0 to 31, man is in the range 0 to 2^32-1
+ // time to lose significance... we want m in the range 0 to 2^9-1
+ // rounding presents a minor problem... we first decide which way
+ // we are rounding (based on given rounding direction and possibly
+ // the bits of the mantissa that are to be discarded).
+
+ switch (r) {
+ case round_down: {
+ // just truncate
+ man = man>>(32-9);
+ break;
+ }
+ case round_up: {
+ // check all bits that we are discarding
+ if (man & (-1>>9)) {
+ man = (man>>(32-9)) + 1;
+ if (man == (1<<9)) {
+ // no need to check for round up outside of range
+ man = 0;
+ exp += 1;
+ }
+ } else {
+ man = (man>>(32-9));
+ }
+ break;
+ }
+ case round_nearest: {
+ // check msb that we are discarding
+ if (man & (1<<(32-9-1))) {
+ man = (man>>(32-9)) + 1;
+ if (man == (1<<9)) {
+ // no need to check for round up outside of range
+ man = 0;
+ exp += 1;
+ }
+ } else {
+ man = (man>>(32-9));
+ }
+ break;
+ }
+ }
+
+ } else {
+ // zero rate - not representable
+
+ if (r == round_down) {
+ return -EINVAL;
+ } else {
+ exp = 0;
+ man = 0;
+ }
+
+ }
+
+ PRINTD (DBG_QOS, "rate: man=%u, exp=%hu", man, exp);
+
+ if (bits)
+ *bits = /* (1<<14) | */ (exp<<9) | man;
+
+ if (actual)
+ *actual = (exp >= 9)
+ ? (1 << exp) + (man << (exp-9))
+ : (1 << exp) + ((man + (1<<(9-exp-1))) >> (9-exp));
+
+ return 0;
+}
+
+/********** Linux ATM Operations **********/
+
+// some are not yet implemented while others do not make sense for
+// this device
+
+/********** Open a VC **********/
+
+static int amb_open (struct atm_vcc * atm_vcc)
+{
+ int error;
+
+ struct atm_qos * qos;
+ struct atm_trafprm * txtp;
+ struct atm_trafprm * rxtp;
+ u16 tx_rate_bits;
+ u16 tx_vc_bits = -1; // hush gcc
+ u16 tx_frame_bits = -1; // hush gcc
+
+ amb_dev * dev = AMB_DEV(atm_vcc->dev);
+ amb_vcc * vcc;
+ unsigned char pool = -1; // hush gcc
+ short vpi = atm_vcc->vpi;
+ int vci = atm_vcc->vci;
+
+ PRINTD (DBG_FLOW|DBG_VCC, "amb_open %x %x", vpi, vci);
+
+#ifdef ATM_VPI_UNSPEC
+ // UNSPEC is deprecated, remove this code eventually
+ if (vpi == ATM_VPI_UNSPEC || vci == ATM_VCI_UNSPEC) {
+ PRINTK (KERN_WARNING, "rejecting open with unspecified VPI/VCI (deprecated)");
+ return -EINVAL;
+ }
+#endif
+
+ if (!(0 <= vpi && vpi < (1<<NUM_VPI_BITS) &&
+ 0 <= vci && vci < (1<<NUM_VCI_BITS))) {
+ PRINTD (DBG_WARN|DBG_VCC, "VPI/VCI out of range: %hd/%d", vpi, vci);
+ return -EINVAL;
+ }
+
+ qos = &atm_vcc->qos;
+
+ if (qos->aal != ATM_AAL5) {
+ PRINTD (DBG_QOS, "AAL not supported");
+ return -EINVAL;
+ }
+
+ // traffic parameters
+
+ PRINTD (DBG_QOS, "TX:");
+ txtp = &qos->txtp;
+ if (txtp->traffic_class != ATM_NONE) {
+ switch (txtp->traffic_class) {
+ case ATM_UBR: {
+ // we take "the PCR" as a rate-cap
+ int pcr = atm_pcr_goal (txtp);
+ if (!pcr) {
+ // no rate cap
+ tx_rate_bits = 0;
+ tx_vc_bits = TX_UBR;
+ tx_frame_bits = TX_FRAME_NOTCAP;
+ } else {
+ rounding r;
+ if (pcr < 0) {
+ r = round_down;
+ pcr = -pcr;
+ } else {
+ r = round_up;
+ }
+ error = make_rate (pcr, r, &tx_rate_bits, NULL);
+ tx_vc_bits = TX_UBR_CAPPED;
+ tx_frame_bits = TX_FRAME_CAPPED;
+ }
+ break;
+ }
+#if 0
+ case ATM_ABR: {
+ pcr = atm_pcr_goal (txtp);
+ PRINTD (DBG_QOS, "pcr goal = %d", pcr);
+ break;
+ }
+#endif
+ default: {
+ // PRINTD (DBG_QOS, "request for non-UBR/ABR denied");
+ PRINTD (DBG_QOS, "request for non-UBR denied");
+ return -EINVAL;
+ }
+ }
+ PRINTD (DBG_QOS, "tx_rate_bits=%hx, tx_vc_bits=%hx",
+ tx_rate_bits, tx_vc_bits);
+ }
+
+ PRINTD (DBG_QOS, "RX:");
+ rxtp = &qos->rxtp;
+ if (rxtp->traffic_class == ATM_NONE) {
+ // do nothing
+ } else {
+ // choose an RX pool (arranged in increasing size)
+ for (pool = 0; pool < NUM_RX_POOLS; ++pool)
+ if ((unsigned int) rxtp->max_sdu <= dev->rxq[pool].buffer_size) {
+ PRINTD (DBG_VCC|DBG_QOS|DBG_POOL, "chose pool %hu (max_sdu %u <= %u)",
+ pool, rxtp->max_sdu, dev->rxq[pool].buffer_size);
+ break;
+ }
+ if (pool == NUM_RX_POOLS) {
+ PRINTD (DBG_WARN|DBG_VCC|DBG_QOS|DBG_POOL,
+ "no pool suitable for VC (RX max_sdu %d is too large)",
+ rxtp->max_sdu);
+ return -EINVAL;
+ }
+
+ switch (rxtp->traffic_class) {
+ case ATM_UBR: {
+ break;
+ }
+#if 0
+ case ATM_ABR: {
+ pcr = atm_pcr_goal (rxtp);
+ PRINTD (DBG_QOS, "pcr goal = %d", pcr);
+ break;
+ }
+#endif
+ default: {
+ // PRINTD (DBG_QOS, "request for non-UBR/ABR denied");
+ PRINTD (DBG_QOS, "request for non-UBR denied");
+ return -EINVAL;
+ }
+ }
+ }
+
+ // get space for our vcc stuff
+ vcc = kmalloc (sizeof(amb_vcc), GFP_KERNEL);
+ if (!vcc) {
+ PRINTK (KERN_ERR, "out of memory!");
+ return -ENOMEM;
+ }
+ atm_vcc->dev_data = (void *) vcc;
+
+ // no failures beyond this point
+
+ // we are not really "immediately before allocating the connection
+ // identifier in hardware", but it will just have to do!
+ set_bit(ATM_VF_ADDR,&atm_vcc->flags);
+
+ if (txtp->traffic_class != ATM_NONE) {
+ command cmd;
+
+ vcc->tx_frame_bits = tx_frame_bits;
+
+ down (&dev->vcc_sf);
+ if (dev->rxer[vci]) {
+ // RXer on the channel already, just modify rate...
+ cmd.request = cpu_to_be32 (SRB_MODIFY_VC_RATE);
+ cmd.args.modify_rate.vc = cpu_to_be32 (vci); // vpi 0
+ cmd.args.modify_rate.rate = cpu_to_be32 (tx_rate_bits << SRB_RATE_SHIFT);
+ while (command_do (dev, &cmd))
+ schedule();
+ // ... and TX flags, preserving the RX pool
+ cmd.request = cpu_to_be32 (SRB_MODIFY_VC_FLAGS);
+ cmd.args.modify_flags.vc = cpu_to_be32 (vci); // vpi 0
+ cmd.args.modify_flags.flags = cpu_to_be32
+ ( (AMB_VCC(dev->rxer[vci])->rx_info.pool << SRB_POOL_SHIFT)
+ | (tx_vc_bits << SRB_FLAGS_SHIFT) );
+ while (command_do (dev, &cmd))
+ schedule();
+ } else {
+ // no RXer on the channel, just open (with pool zero)
+ cmd.request = cpu_to_be32 (SRB_OPEN_VC);
+ cmd.args.open.vc = cpu_to_be32 (vci); // vpi 0
+ cmd.args.open.flags = cpu_to_be32 (tx_vc_bits << SRB_FLAGS_SHIFT);
+ cmd.args.open.rate = cpu_to_be32 (tx_rate_bits << SRB_RATE_SHIFT);
+ while (command_do (dev, &cmd))
+ schedule();
+ }
+ dev->txer[vci].tx_present = 1;
+ up (&dev->vcc_sf);
+ }
+
+ if (rxtp->traffic_class != ATM_NONE) {
+ command cmd;
+
+ vcc->rx_info.pool = pool;
+
+ down (&dev->vcc_sf);
+ /* grow RX buffer pool */
+ if (!dev->rxq[pool].buffers_wanted)
+ dev->rxq[pool].buffers_wanted = rx_lats;
+ dev->rxq[pool].buffers_wanted += 1;
+ fill_rx_pool (dev, pool, GFP_KERNEL);
+
+ if (dev->txer[vci].tx_present) {
+ // TXer on the channel already
+ // switch (from pool zero) to this pool, preserving the TX bits
+ cmd.request = cpu_to_be32 (SRB_MODIFY_VC_FLAGS);
+ cmd.args.modify_flags.vc = cpu_to_be32 (vci); // vpi 0
+ cmd.args.modify_flags.flags = cpu_to_be32
+ ( (pool << SRB_POOL_SHIFT)
+ | (dev->txer[vci].tx_vc_bits << SRB_FLAGS_SHIFT) );
+ } else {
+ // no TXer on the channel, open the VC (with no rate info)
+ cmd.request = cpu_to_be32 (SRB_OPEN_VC);
+ cmd.args.open.vc = cpu_to_be32 (vci); // vpi 0
+ cmd.args.open.flags = cpu_to_be32 (pool << SRB_POOL_SHIFT);
+ cmd.args.open.rate = cpu_to_be32 (0);
+ }
+ while (command_do (dev, &cmd))
+ schedule();
+ // this link allows RX frames through
+ dev->rxer[vci] = atm_vcc;
+ up (&dev->vcc_sf);
+ }
+
+ // indicate readiness
+ set_bit(ATM_VF_READY,&atm_vcc->flags);
+
+ return 0;
+}
+
+/********** Close a VC **********/
+
+static void amb_close (struct atm_vcc * atm_vcc) {
+ amb_dev * dev = AMB_DEV (atm_vcc->dev);
+ amb_vcc * vcc = AMB_VCC (atm_vcc);
+ u16 vci = atm_vcc->vci;
+
+ PRINTD (DBG_VCC|DBG_FLOW, "amb_close");
+
+ // indicate unreadiness
+ clear_bit(ATM_VF_READY,&atm_vcc->flags);
+
+ // disable TXing
+ if (atm_vcc->qos.txtp.traffic_class != ATM_NONE) {
+ command cmd;
+
+ down (&dev->vcc_sf);
+ if (dev->rxer[vci]) {
+ // RXer still on the channel, just modify rate... XXX not really needed
+ cmd.request = cpu_to_be32 (SRB_MODIFY_VC_RATE);
+ cmd.args.modify_rate.vc = cpu_to_be32 (vci); // vpi 0
+ cmd.args.modify_rate.rate = cpu_to_be32 (0);
+ // ... and clear TX rate flags (XXX to stop RM cell output?), preserving RX pool
+ } else {
+ // no RXer on the channel, close channel
+ cmd.request = cpu_to_be32 (SRB_CLOSE_VC);
+ cmd.args.close.vc = cpu_to_be32 (vci); // vpi 0
+ }
+ dev->txer[vci].tx_present = 0;
+ while (command_do (dev, &cmd))
+ schedule();
+ up (&dev->vcc_sf);
+ }
+
+ // disable RXing
+ if (atm_vcc->qos.rxtp.traffic_class != ATM_NONE) {
+ command cmd;
+
+ // this is (the?) one reason why we need the amb_vcc struct
+ unsigned char pool = vcc->rx_info.pool;
+
+ down (&dev->vcc_sf);
+ if (dev->txer[vci].tx_present) {
+ // TXer still on the channel, just go to pool zero XXX not really needed
+ cmd.request = cpu_to_be32 (SRB_MODIFY_VC_FLAGS);
+ cmd.args.modify_flags.vc = cpu_to_be32 (vci); // vpi 0
+ cmd.args.modify_flags.flags = cpu_to_be32
+ (dev->txer[vci].tx_vc_bits << SRB_FLAGS_SHIFT);
+ } else {
+ // no TXer on the channel, close the VC
+ cmd.request = cpu_to_be32 (SRB_CLOSE_VC);
+ cmd.args.close.vc = cpu_to_be32 (vci); // vpi 0
+ }
+ // forget the rxer - no more skbs will be pushed
+ if (atm_vcc != dev->rxer[vci])
+ PRINTK (KERN_ERR, "%s vcc=%p rxer[vci]=%p",
+ "arghhh! we're going to die!",
+ vcc, dev->rxer[vci]);
+ dev->rxer[vci] = NULL;
+ while (command_do (dev, &cmd))
+ schedule();
+
+ /* shrink RX buffer pool */
+ dev->rxq[pool].buffers_wanted -= 1;
+ if (dev->rxq[pool].buffers_wanted == rx_lats) {
+ dev->rxq[pool].buffers_wanted = 0;
+ drain_rx_pool (dev, pool);
+ }
+ up (&dev->vcc_sf);
+ }
+
+ // free our structure
+ kfree (vcc);
+
+ // say the VPI/VCI is free again
+ clear_bit(ATM_VF_ADDR,&atm_vcc->flags);
+
+ return;
+}
+
+/********** Set socket options for a VC **********/
+
+// int amb_getsockopt (struct atm_vcc * atm_vcc, int level, int optname, void * optval, int optlen);
+
+/********** Set socket options for a VC **********/
+
+// int amb_setsockopt (struct atm_vcc * atm_vcc, int level, int optname, void * optval, int optlen);
+
+/********** Send **********/
+
+static int amb_send (struct atm_vcc * atm_vcc, struct sk_buff * skb) {
+ amb_dev * dev = AMB_DEV(atm_vcc->dev);
+ amb_vcc * vcc = AMB_VCC(atm_vcc);
+ u16 vc = atm_vcc->vci;
+ unsigned int tx_len = skb->len;
+ unsigned char * tx_data = skb->data;
+ tx_simple * tx_descr;
+ tx_in tx;
+
+ if (test_bit (dead, &dev->flags))
+ return -EIO;
+
+ PRINTD (DBG_FLOW|DBG_TX, "amb_send vc %x data %p len %u",
+ vc, tx_data, tx_len);
+
+ dump_skb (">>>", vc, skb);
+
+ if (!dev->txer[vc].tx_present) {
+ PRINTK (KERN_ERR, "attempt to send on RX-only VC %x", vc);
+ return -EBADFD;
+ }
+
+ // this is a driver private field so we have to set it ourselves,
+ // despite the fact that we are _required_ to use it to check for a
+ // pop function
+ ATM_SKB(skb)->vcc = atm_vcc;
+
+ if (skb->len > (size_t) atm_vcc->qos.txtp.max_sdu) {
+ PRINTK (KERN_ERR, "sk_buff length greater than agreed max_sdu, dropping...");
+ return -EIO;
+ }
+
+ if (check_area (skb->data, skb->len)) {
+ atomic_inc(&atm_vcc->stats->tx_err);
+ return -ENOMEM; // ?
+ }
+
+ // allocate memory for fragments
+ tx_descr = kmalloc (sizeof(tx_simple), GFP_KERNEL);
+ if (!tx_descr) {
+ PRINTK (KERN_ERR, "could not allocate TX descriptor");
+ return -ENOMEM;
+ }
+ if (check_area (tx_descr, sizeof(tx_simple))) {
+ kfree (tx_descr);
+ return -ENOMEM;
+ }
+ PRINTD (DBG_TX, "fragment list allocated at %p", tx_descr);
+
+ tx_descr->skb = skb;
+
+ tx_descr->tx_frag.bytes = cpu_to_be32 (tx_len);
+ tx_descr->tx_frag.address = cpu_to_be32 (virt_to_bus (tx_data));
+
+ tx_descr->tx_frag_end.handle = virt_to_bus (tx_descr);
+ tx_descr->tx_frag_end.vc = 0;
+ tx_descr->tx_frag_end.next_descriptor_length = 0;
+ tx_descr->tx_frag_end.next_descriptor = 0;
+#ifdef AMB_NEW_MICROCODE
+ tx_descr->tx_frag_end.cpcs_uu = 0;
+ tx_descr->tx_frag_end.cpi = 0;
+ tx_descr->tx_frag_end.pad = 0;
+#endif
+
+ tx.vc = cpu_to_be16 (vcc->tx_frame_bits | vc);
+ tx.tx_descr_length = cpu_to_be16 (sizeof(tx_frag)+sizeof(tx_frag_end));
+ tx.tx_descr_addr = cpu_to_be32 (virt_to_bus (&tx_descr->tx_frag));
+
+ while (tx_give (dev, &tx))
+ schedule();
+ return 0;
+}
+
+/********** Change QoS on a VC **********/
+
+// int amb_change_qos (struct atm_vcc * atm_vcc, struct atm_qos * qos, int flags);
+
+/********** Free RX Socket Buffer **********/
+
+#if 0
+static void amb_free_rx_skb (struct atm_vcc * atm_vcc, struct sk_buff * skb) {
+ amb_dev * dev = AMB_DEV (atm_vcc->dev);
+ amb_vcc * vcc = AMB_VCC (atm_vcc);
+ unsigned char pool = vcc->rx_info.pool;
+ rx_in rx;
+
+ // This may be unsafe for various reasons that I cannot really guess
+ // at. However, I note that the ATM layer calls kfree_skb rather
+ // than dev_kfree_skb at this point so we are least covered as far
+ // as buffer locking goes. There may be bugs if pcap clones RX skbs.
+
+ PRINTD (DBG_FLOW|DBG_SKB, "amb_rx_free skb %p (atm_vcc %p, vcc %p)",
+ skb, atm_vcc, vcc);
+
+ rx.handle = virt_to_bus (skb);
+ rx.host_address = cpu_to_be32 (virt_to_bus (skb->data));
+
+ skb->data = skb->head;
+ skb->tail = skb->head;
+ skb->len = 0;
+
+ if (!rx_give (dev, &rx, pool)) {
+ // success
+ PRINTD (DBG_SKB|DBG_POOL, "recycled skb for pool %hu", pool);
+ return;
+ }
+
+ // just do what the ATM layer would have done
+ dev_kfree_skb_any (skb);
+
+ return;
+}
+#endif
+
+/********** Proc File Output **********/
+
+static int amb_proc_read (struct atm_dev * atm_dev, loff_t * pos, char * page) {
+ amb_dev * dev = AMB_DEV (atm_dev);
+ int left = *pos;
+ unsigned char pool;
+
+ PRINTD (DBG_FLOW, "amb_proc_read");
+
+ /* more diagnostics here? */
+
+ if (!left--) {
+ amb_stats * s = &dev->stats;
+ return sprintf (page,
+ "frames: TX OK %lu, RX OK %lu, RX bad %lu "
+ "(CRC %lu, long %lu, aborted %lu, unused %lu).\n",
+ s->tx_ok, s->rx.ok, s->rx.error,
+ s->rx.badcrc, s->rx.toolong,
+ s->rx.aborted, s->rx.unused);
+ }
+
+ if (!left--) {
+ amb_cq * c = &dev->cq;
+ return sprintf (page, "cmd queue [cur/hi/max]: %u/%u/%u. ",
+ c->pending, c->high, c->maximum);
+ }
+
+ if (!left--) {
+ amb_txq * t = &dev->txq;
+ return sprintf (page, "TX queue [cur/max high full]: %u/%u %u %u.\n",
+ t->pending, t->maximum, t->high, t->filled);
+ }
+
+ if (!left--) {
+ unsigned int count = sprintf (page, "RX queues [cur/max/req low empty]:");
+ for (pool = 0; pool < NUM_RX_POOLS; ++pool) {
+ amb_rxq * r = &dev->rxq[pool];
+ count += sprintf (page+count, " %u/%u/%u %u %u",
+ r->pending, r->maximum, r->buffers_wanted, r->low, r->emptied);
+ }
+ count += sprintf (page+count, ".\n");
+ return count;
+ }
+
+ if (!left--) {
+ unsigned int count = sprintf (page, "RX buffer sizes:");
+ for (pool = 0; pool < NUM_RX_POOLS; ++pool) {
+ amb_rxq * r = &dev->rxq[pool];
+ count += sprintf (page+count, " %u", r->buffer_size);
+ }
+ count += sprintf (page+count, ".\n");
+ return count;
+ }
+
+#if 0
+ if (!left--) {
+ // suni block etc?
+ }
+#endif
+
+ return 0;
+}
+
+/********** Operation Structure **********/
+
+static const struct atmdev_ops amb_ops = {
+ .open = amb_open,
+ .close = amb_close,
+ .send = amb_send,
+ .proc_read = amb_proc_read,
+ .owner = THIS_MODULE,
+};
+
+/********** housekeeping **********/
+static void do_housekeeping (unsigned long arg) {
+ amb_dev * dev = (amb_dev *) arg;
+
+ // could collect device-specific (not driver/atm-linux) stats here
+
+ // last resort refill once every ten seconds
+ fill_rx_pools (dev);
+ mod_timer(&dev->housekeeping, jiffies + 10*HZ);
+
+ return;
+}
+
+/********** creation of communication queues **********/
+
+static int __devinit create_queues (amb_dev * dev, unsigned int cmds,
+ unsigned int txs, unsigned int * rxs,
+ unsigned int * rx_buffer_sizes) {
+ unsigned char pool;
+ size_t total = 0;
+ void * memory;
+ void * limit;
+
+ PRINTD (DBG_FLOW, "create_queues %p", dev);
+
+ total += cmds * sizeof(command);
+
+ total += txs * (sizeof(tx_in) + sizeof(tx_out));
+
+ for (pool = 0; pool < NUM_RX_POOLS; ++pool)
+ total += rxs[pool] * (sizeof(rx_in) + sizeof(rx_out));
+
+ memory = kmalloc (total, GFP_KERNEL);
+ if (!memory) {
+ PRINTK (KERN_ERR, "could not allocate queues");
+ return -ENOMEM;
+ }
+ if (check_area (memory, total)) {
+ PRINTK (KERN_ERR, "queues allocated in nasty area");
+ kfree (memory);
+ return -ENOMEM;
+ }
+
+ limit = memory + total;
+ PRINTD (DBG_INIT, "queues from %p to %p", memory, limit);
+
+ PRINTD (DBG_CMD, "command queue at %p", memory);
+
+ {
+ command * cmd = memory;
+ amb_cq * cq = &dev->cq;
+
+ cq->pending = 0;
+ cq->high = 0;
+ cq->maximum = cmds - 1;
+
+ cq->ptrs.start = cmd;
+ cq->ptrs.in = cmd;
+ cq->ptrs.out = cmd;
+ cq->ptrs.limit = cmd + cmds;
+
+ memory = cq->ptrs.limit;
+ }
+
+ PRINTD (DBG_TX, "TX queue pair at %p", memory);
+
+ {
+ tx_in * in = memory;
+ tx_out * out;
+ amb_txq * txq = &dev->txq;
+
+ txq->pending = 0;
+ txq->high = 0;
+ txq->filled = 0;
+ txq->maximum = txs - 1;
+
+ txq->in.start = in;
+ txq->in.ptr = in;
+ txq->in.limit = in + txs;
+
+ memory = txq->in.limit;
+ out = memory;
+
+ txq->out.start = out;
+ txq->out.ptr = out;
+ txq->out.limit = out + txs;
+
+ memory = txq->out.limit;
+ }
+
+ PRINTD (DBG_RX, "RX queue pairs at %p", memory);
+
+ for (pool = 0; pool < NUM_RX_POOLS; ++pool) {
+ rx_in * in = memory;
+ rx_out * out;
+ amb_rxq * rxq = &dev->rxq[pool];
+
+ rxq->buffer_size = rx_buffer_sizes[pool];
+ rxq->buffers_wanted = 0;
+
+ rxq->pending = 0;
+ rxq->low = rxs[pool] - 1;
+ rxq->emptied = 0;
+ rxq->maximum = rxs[pool] - 1;
+
+ rxq->in.start = in;
+ rxq->in.ptr = in;
+ rxq->in.limit = in + rxs[pool];
+
+ memory = rxq->in.limit;
+ out = memory;
+
+ rxq->out.start = out;
+ rxq->out.ptr = out;
+ rxq->out.limit = out + rxs[pool];
+
+ memory = rxq->out.limit;
+ }
+
+ if (memory == limit) {
+ return 0;
+ } else {
+ PRINTK (KERN_ERR, "bad queue alloc %p != %p (tell maintainer)", memory, limit);
+ kfree (limit - total);
+ return -ENOMEM;
+ }
+
+}
+
+/********** destruction of communication queues **********/
+
+static void destroy_queues (amb_dev * dev) {
+ // all queues assumed empty
+ void * memory = dev->cq.ptrs.start;
+ // includes txq.in, txq.out, rxq[].in and rxq[].out
+
+ PRINTD (DBG_FLOW, "destroy_queues %p", dev);
+
+ PRINTD (DBG_INIT, "freeing queues at %p", memory);
+ kfree (memory);
+
+ return;
+}
+
+/********** basic loader commands and error handling **********/
+// centisecond timeouts - guessing away here
+static unsigned int command_timeouts [] = {
+ [host_memory_test] = 15,
+ [read_adapter_memory] = 2,
+ [write_adapter_memory] = 2,
+ [adapter_start] = 50,
+ [get_version_number] = 10,
+ [interrupt_host] = 1,
+ [flash_erase_sector] = 1,
+ [adap_download_block] = 1,
+ [adap_erase_flash] = 1,
+ [adap_run_in_iram] = 1,
+ [adap_end_download] = 1
+};
+
+
+static unsigned int command_successes [] = {
+ [host_memory_test] = COMMAND_PASSED_TEST,
+ [read_adapter_memory] = COMMAND_READ_DATA_OK,
+ [write_adapter_memory] = COMMAND_WRITE_DATA_OK,
+ [adapter_start] = COMMAND_COMPLETE,
+ [get_version_number] = COMMAND_COMPLETE,
+ [interrupt_host] = COMMAND_COMPLETE,
+ [flash_erase_sector] = COMMAND_COMPLETE,
+ [adap_download_block] = COMMAND_COMPLETE,
+ [adap_erase_flash] = COMMAND_COMPLETE,
+ [adap_run_in_iram] = COMMAND_COMPLETE,
+ [adap_end_download] = COMMAND_COMPLETE
+};
+
+static int decode_loader_result (loader_command cmd, u32 result)
+{
+ int res;
+ const char *msg;
+
+ if (result == command_successes[cmd])
+ return 0;
+
+ switch (result) {
+ case BAD_COMMAND:
+ res = -EINVAL;
+ msg = "bad command";
+ break;
+ case COMMAND_IN_PROGRESS:
+ res = -ETIMEDOUT;
+ msg = "command in progress";
+ break;
+ case COMMAND_PASSED_TEST:
+ res = 0;
+ msg = "command passed test";
+ break;
+ case COMMAND_FAILED_TEST:
+ res = -EIO;
+ msg = "command failed test";
+ break;
+ case COMMAND_READ_DATA_OK:
+ res = 0;
+ msg = "command read data ok";
+ break;
+ case COMMAND_READ_BAD_ADDRESS:
+ res = -EINVAL;
+ msg = "command read bad address";
+ break;
+ case COMMAND_WRITE_DATA_OK:
+ res = 0;
+ msg = "command write data ok";
+ break;
+ case COMMAND_WRITE_BAD_ADDRESS:
+ res = -EINVAL;
+ msg = "command write bad address";
+ break;
+ case COMMAND_WRITE_FLASH_FAILURE:
+ res = -EIO;
+ msg = "command write flash failure";
+ break;
+ case COMMAND_COMPLETE:
+ res = 0;
+ msg = "command complete";
+ break;
+ case COMMAND_FLASH_ERASE_FAILURE:
+ res = -EIO;
+ msg = "command flash erase failure";
+ break;
+ case COMMAND_WRITE_BAD_DATA:
+ res = -EINVAL;
+ msg = "command write bad data";
+ break;
+ default:
+ res = -EINVAL;
+ msg = "unknown error";
+ PRINTD (DBG_LOAD|DBG_ERR,
+ "decode_loader_result got %d=%x !",
+ result, result);
+ break;
+ }
+
+ PRINTK (KERN_ERR, "%s", msg);
+ return res;
+}
+
+static int __devinit do_loader_command (volatile loader_block * lb,
+ const amb_dev * dev, loader_command cmd) {
+
+ unsigned long timeout;
+
+ PRINTD (DBG_FLOW|DBG_LOAD, "do_loader_command");
+
+ /* do a command
+
+ Set the return value to zero, set the command type and set the
+ valid entry to the right magic value. The payload is already
+ correctly byte-ordered so we leave it alone. Hit the doorbell
+ with the bus address of this structure.
+
+ */
+
+ lb->result = 0;
+ lb->command = cpu_to_be32 (cmd);
+ lb->valid = cpu_to_be32 (DMA_VALID);
+ // dump_registers (dev);
+ // dump_loader_block (lb);
+ wr_mem (dev, offsetof(amb_mem, doorbell), virt_to_bus (lb) & ~onegigmask);
+
+ timeout = command_timeouts[cmd] * 10;
+
+ while (!lb->result || lb->result == cpu_to_be32 (COMMAND_IN_PROGRESS))
+ if (timeout) {
+ timeout = msleep_interruptible(timeout);
+ } else {
+ PRINTD (DBG_LOAD|DBG_ERR, "command %d timed out", cmd);
+ dump_registers (dev);
+ dump_loader_block (lb);
+ return -ETIMEDOUT;
+ }
+
+ if (cmd == adapter_start) {
+ // wait for start command to acknowledge...
+ timeout = 100;
+ while (rd_plain (dev, offsetof(amb_mem, doorbell)))
+ if (timeout) {
+ timeout = msleep_interruptible(timeout);
+ } else {
+ PRINTD (DBG_LOAD|DBG_ERR, "start command did not clear doorbell, res=%08x",
+ be32_to_cpu (lb->result));
+ dump_registers (dev);
+ return -ETIMEDOUT;
+ }
+ return 0;
+ } else {
+ return decode_loader_result (cmd, be32_to_cpu (lb->result));
+ }
+
+}
+
+/* loader: determine loader version */
+
+static int __devinit get_loader_version (loader_block * lb,
+ const amb_dev * dev, u32 * version) {
+ int res;
+
+ PRINTD (DBG_FLOW|DBG_LOAD, "get_loader_version");
+
+ res = do_loader_command (lb, dev, get_version_number);
+ if (res)
+ return res;
+ if (version)
+ *version = be32_to_cpu (lb->payload.version);
+ return 0;
+}
+
+/* loader: write memory data blocks */
+
+static int __devinit loader_write (loader_block * lb,
+ const amb_dev * dev, const u32 * data,
+ u32 address, unsigned int count) {
+ unsigned int i;
+ transfer_block * tb = &lb->payload.transfer;
+
+ PRINTD (DBG_FLOW|DBG_LOAD, "loader_write");
+
+ if (count > MAX_TRANSFER_DATA)
+ return -EINVAL;
+ tb->address = cpu_to_be32 (address);
+ tb->count = cpu_to_be32 (count);
+ for (i = 0; i < count; ++i)
+ tb->data[i] = cpu_to_be32 (data[i]);
+ return do_loader_command (lb, dev, write_adapter_memory);
+}
+
+/* loader: verify memory data blocks */
+
+static int __devinit loader_verify (loader_block * lb,
+ const amb_dev * dev, const u32 * data,
+ u32 address, unsigned int count) {
+ unsigned int i;
+ transfer_block * tb = &lb->payload.transfer;
+ int res;
+
+ PRINTD (DBG_FLOW|DBG_LOAD, "loader_verify");
+
+ if (count > MAX_TRANSFER_DATA)
+ return -EINVAL;
+ tb->address = cpu_to_be32 (address);
+ tb->count = cpu_to_be32 (count);
+ res = do_loader_command (lb, dev, read_adapter_memory);
+ if (!res)
+ for (i = 0; i < count; ++i)
+ if (tb->data[i] != cpu_to_be32 (data[i])) {
+ res = -EINVAL;
+ break;
+ }
+ return res;
+}
+
+/* loader: start microcode */
+
+static int __devinit loader_start (loader_block * lb,
+ const amb_dev * dev, u32 address) {
+ PRINTD (DBG_FLOW|DBG_LOAD, "loader_start");
+
+ lb->payload.start = cpu_to_be32 (address);
+ return do_loader_command (lb, dev, adapter_start);
+}
+
+/********** reset card **********/
+
+static inline void sf (const char * msg)
+{
+ PRINTK (KERN_ERR, "self-test failed: %s", msg);
+}
+
+static int amb_reset (amb_dev * dev, int diags) {
+ u32 word;
+
+ PRINTD (DBG_FLOW|DBG_LOAD, "amb_reset");
+
+ word = rd_plain (dev, offsetof(amb_mem, reset_control));
+ // put card into reset state
+ wr_plain (dev, offsetof(amb_mem, reset_control), word | AMB_RESET_BITS);
+ // wait a short while
+ udelay (10);
+#if 1
+ // put card into known good state
+ wr_plain (dev, offsetof(amb_mem, interrupt_control), AMB_DOORBELL_BITS);
+ // clear all interrupts just in case
+ wr_plain (dev, offsetof(amb_mem, interrupt), -1);
+#endif
+ // clear self-test done flag
+ wr_plain (dev, offsetof(amb_mem, mb.loader.ready), 0);
+ // take card out of reset state
+ wr_plain (dev, offsetof(amb_mem, reset_control), word &~ AMB_RESET_BITS);
+
+ if (diags) {
+ unsigned long timeout;
+ // 4.2 second wait
+ msleep(4200);
+ // half second time-out
+ timeout = 500;
+ while (!rd_plain (dev, offsetof(amb_mem, mb.loader.ready)))
+ if (timeout) {
+ timeout = msleep_interruptible(timeout);
+ } else {
+ PRINTD (DBG_LOAD|DBG_ERR, "reset timed out");
+ return -ETIMEDOUT;
+ }
+
+ // get results of self-test
+ // XXX double check byte-order
+ word = rd_mem (dev, offsetof(amb_mem, mb.loader.result));
+ if (word & SELF_TEST_FAILURE) {
+ if (word & GPINT_TST_FAILURE)
+ sf ("interrupt");
+ if (word & SUNI_DATA_PATTERN_FAILURE)
+ sf ("SUNI data pattern");
+ if (word & SUNI_DATA_BITS_FAILURE)
+ sf ("SUNI data bits");
+ if (word & SUNI_UTOPIA_FAILURE)
+ sf ("SUNI UTOPIA interface");
+ if (word & SUNI_FIFO_FAILURE)
+ sf ("SUNI cell buffer FIFO");
+ if (word & SRAM_FAILURE)
+ sf ("bad SRAM");
+ // better return value?
+ return -EIO;
+ }
+
+ }
+ return 0;
+}
+
+/********** transfer and start the microcode **********/
+
+static int __devinit ucode_init (loader_block * lb, amb_dev * dev) {
+ unsigned int i = 0;
+ unsigned int total = 0;
+ const u32 * pointer = ucode_data;
+ u32 address;
+ unsigned int count;
+ int res;
+
+ PRINTD (DBG_FLOW|DBG_LOAD, "ucode_init");
+
+ while (address = ucode_regions[i].start,
+ count = ucode_regions[i].count) {
+ PRINTD (DBG_LOAD, "starting region (%x, %u)", address, count);
+ while (count) {
+ unsigned int words;
+ if (count <= MAX_TRANSFER_DATA)
+ words = count;
+ else
+ words = MAX_TRANSFER_DATA;
+ total += words;
+ res = loader_write (lb, dev, pointer, address, words);
+ if (res)
+ return res;
+ res = loader_verify (lb, dev, pointer, address, words);
+ if (res)
+ return res;
+ count -= words;
+ address += sizeof(u32) * words;
+ pointer += words;
+ }
+ i += 1;
+ }
+ if (*pointer == 0xdeadbeef) {
+ return loader_start (lb, dev, ucode_start);
+ } else {
+ // cast needed as there is no %? for pointer differnces
+ PRINTD (DBG_LOAD|DBG_ERR,
+ "offset=%li, *pointer=%x, address=%x, total=%u",
+ (long) (pointer - ucode_data), *pointer, address, total);
+ PRINTK (KERN_ERR, "incorrect microcode data");
+ return -ENOMEM;
+ }
+}
+
+/********** give adapter parameters **********/
+
+static inline __be32 bus_addr(void * addr) {
+ return cpu_to_be32 (virt_to_bus (addr));
+}
+
+static int __devinit amb_talk (amb_dev * dev) {
+ adap_talk_block a;
+ unsigned char pool;
+ unsigned long timeout;
+
+ PRINTD (DBG_FLOW, "amb_talk %p", dev);
+
+ a.command_start = bus_addr (dev->cq.ptrs.start);
+ a.command_end = bus_addr (dev->cq.ptrs.limit);
+ a.tx_start = bus_addr (dev->txq.in.start);
+ a.tx_end = bus_addr (dev->txq.in.limit);
+ a.txcom_start = bus_addr (dev->txq.out.start);
+ a.txcom_end = bus_addr (dev->txq.out.limit);
+
+ for (pool = 0; pool < NUM_RX_POOLS; ++pool) {
+ // the other "a" items are set up by the adapter
+ a.rec_struct[pool].buffer_start = bus_addr (dev->rxq[pool].in.start);
+ a.rec_struct[pool].buffer_end = bus_addr (dev->rxq[pool].in.limit);
+ a.rec_struct[pool].rx_start = bus_addr (dev->rxq[pool].out.start);
+ a.rec_struct[pool].rx_end = bus_addr (dev->rxq[pool].out.limit);
+ a.rec_struct[pool].buffer_size = cpu_to_be32 (dev->rxq[pool].buffer_size);
+ }
+
+#ifdef AMB_NEW_MICROCODE
+ // disable fast PLX prefetching
+ a.init_flags = 0;
+#endif
+
+ // pass the structure
+ wr_mem (dev, offsetof(amb_mem, doorbell), virt_to_bus (&a));
+
+ // 2.2 second wait (must not touch doorbell during 2 second DMA test)
+ msleep(2200);
+ // give the adapter another half second?
+ timeout = 500;
+ while (rd_plain (dev, offsetof(amb_mem, doorbell)))
+ if (timeout) {
+ timeout = msleep_interruptible(timeout);
+ } else {
+ PRINTD (DBG_INIT|DBG_ERR, "adapter init timed out");
+ return -ETIMEDOUT;
+ }
+
+ return 0;
+}
+
+// get microcode version
+static void __devinit amb_ucode_version (amb_dev * dev) {
+ u32 major;
+ u32 minor;
+ command cmd;
+ cmd.request = cpu_to_be32 (SRB_GET_VERSION);
+ while (command_do (dev, &cmd)) {
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ schedule();
+ }
+ major = be32_to_cpu (cmd.args.version.major);
+ minor = be32_to_cpu (cmd.args.version.minor);
+ PRINTK (KERN_INFO, "microcode version is %u.%u", major, minor);
+}
+
+// swap bits within byte to get Ethernet ordering
+static u8 bit_swap (u8 byte)
+{
+ const u8 swap[] = {
+ 0x0, 0x8, 0x4, 0xc,
+ 0x2, 0xa, 0x6, 0xe,
+ 0x1, 0x9, 0x5, 0xd,
+ 0x3, 0xb, 0x7, 0xf
+ };
+ return ((swap[byte & 0xf]<<4) | swap[byte>>4]);
+}
+
+// get end station address
+static void __devinit amb_esi (amb_dev * dev, u8 * esi) {
+ u32 lower4;
+ u16 upper2;
+ command cmd;
+
+ cmd.request = cpu_to_be32 (SRB_GET_BIA);
+ while (command_do (dev, &cmd)) {
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ schedule();
+ }
+ lower4 = be32_to_cpu (cmd.args.bia.lower4);
+ upper2 = be32_to_cpu (cmd.args.bia.upper2);
+ PRINTD (DBG_LOAD, "BIA: lower4: %08x, upper2 %04x", lower4, upper2);
+
+ if (esi) {
+ unsigned int i;
+
+ PRINTDB (DBG_INIT, "ESI:");
+ for (i = 0; i < ESI_LEN; ++i) {
+ if (i < 4)
+ esi[i] = bit_swap (lower4>>(8*i));
+ else
+ esi[i] = bit_swap (upper2>>(8*(i-4)));
+ PRINTDM (DBG_INIT, " %02x", esi[i]);
+ }
+
+ PRINTDE (DBG_INIT, "");
+ }
+
+ return;
+}
+
+static void fixup_plx_window (amb_dev *dev, loader_block *lb)
+{
+ // fix up the PLX-mapped window base address to match the block
+ unsigned long blb;
+ u32 mapreg;
+ blb = virt_to_bus(lb);
+ // the kernel stack had better not ever cross a 1Gb boundary!
+ mapreg = rd_plain (dev, offsetof(amb_mem, stuff[10]));
+ mapreg &= ~onegigmask;
+ mapreg |= blb & onegigmask;
+ wr_plain (dev, offsetof(amb_mem, stuff[10]), mapreg);
+ return;
+}
+
+static int __devinit amb_init (amb_dev * dev)
+{
+ loader_block lb;
+
+ u32 version;
+
+ if (amb_reset (dev, 1)) {
+ PRINTK (KERN_ERR, "card reset failed!");
+ } else {
+ fixup_plx_window (dev, &lb);
+
+ if (get_loader_version (&lb, dev, &version)) {
+ PRINTK (KERN_INFO, "failed to get loader version");
+ } else {
+ PRINTK (KERN_INFO, "loader version is %08x", version);
+
+ if (ucode_init (&lb, dev)) {
+ PRINTK (KERN_ERR, "microcode failure");
+ } else if (create_queues (dev, cmds, txs, rxs, rxs_bs)) {
+ PRINTK (KERN_ERR, "failed to get memory for queues");
+ } else {
+
+ if (amb_talk (dev)) {
+ PRINTK (KERN_ERR, "adapter did not accept queues");
+ } else {
+
+ amb_ucode_version (dev);
+ return 0;
+
+ } /* amb_talk */
+
+ destroy_queues (dev);
+ } /* create_queues, ucode_init */
+
+ amb_reset (dev, 0);
+ } /* get_loader_version */
+
+ } /* amb_reset */
+
+ return -EINVAL;
+}
+
+static void setup_dev(amb_dev *dev, struct pci_dev *pci_dev)
+{
+ unsigned char pool;
+ memset (dev, 0, sizeof(amb_dev));
+
+ // set up known dev items straight away
+ dev->pci_dev = pci_dev;
+ pci_set_drvdata(pci_dev, dev);
+
+ dev->iobase = pci_resource_start (pci_dev, 1);
+ dev->irq = pci_dev->irq;
+ dev->membase = bus_to_virt(pci_resource_start(pci_dev, 0));
+
+ // flags (currently only dead)
+ dev->flags = 0;
+
+ // Allocate cell rates (fibre)
+ // ATM_OC3_PCR = 1555200000/8/270*260/53 - 29/53
+ // to be really pedantic, this should be ATM_OC3c_PCR
+ dev->tx_avail = ATM_OC3_PCR;
+ dev->rx_avail = ATM_OC3_PCR;
+
+#ifdef FILL_RX_POOLS_IN_BH
+ // initialise bottom half
+ INIT_WORK(&dev->bh, (void (*)(void *)) fill_rx_pools, dev);
+#endif
+
+ // semaphore for txer/rxer modifications - we cannot use a
+ // spinlock as the critical region needs to switch processes
+ init_MUTEX (&dev->vcc_sf);
+ // queue manipulation spinlocks; we want atomic reads and
+ // writes to the queue descriptors (handles IRQ and SMP)
+ // consider replacing "int pending" -> "atomic_t available"
+ // => problem related to who gets to move queue pointers
+ spin_lock_init (&dev->cq.lock);
+ spin_lock_init (&dev->txq.lock);
+ for (pool = 0; pool < NUM_RX_POOLS; ++pool)
+ spin_lock_init (&dev->rxq[pool].lock);
+}
+
+static void setup_pci_dev(struct pci_dev *pci_dev)
+{
+ unsigned char lat;
+
+ // enable bus master accesses
+ pci_set_master(pci_dev);
+
+ // frobnicate latency (upwards, usually)
+ pci_read_config_byte (pci_dev, PCI_LATENCY_TIMER, &lat);
+
+ if (!pci_lat)
+ pci_lat = (lat < MIN_PCI_LATENCY) ? MIN_PCI_LATENCY : lat;
+
+ if (lat != pci_lat) {
+ PRINTK (KERN_INFO, "Changing PCI latency timer from %hu to %hu",
+ lat, pci_lat);
+ pci_write_config_byte(pci_dev, PCI_LATENCY_TIMER, pci_lat);
+ }
+}
+
+static int __devinit amb_probe(struct pci_dev *pci_dev, const struct pci_device_id *pci_ent)
+{
+ amb_dev * dev;
+ int err;
+ unsigned int irq;
+
+ err = pci_enable_device(pci_dev);
+ if (err < 0) {
+ PRINTK (KERN_ERR, "skipped broken (PLX rev 2) card");
+ goto out;
+ }
+
+ // read resources from PCI configuration space
+ irq = pci_dev->irq;
+
+ if (pci_dev->device == PCI_DEVICE_ID_MADGE_AMBASSADOR_BAD) {
+ PRINTK (KERN_ERR, "skipped broken (PLX rev 2) card");
+ err = -EINVAL;
+ goto out_disable;
+ }
+
+ PRINTD (DBG_INFO, "found Madge ATM adapter (amb) at"
+ " IO %lx, IRQ %u, MEM %p", pci_resource_start(pci_dev, 1),
+ irq, bus_to_virt(pci_resource_start(pci_dev, 0)));
+
+ // check IO region
+ err = pci_request_region(pci_dev, 1, DEV_LABEL);
+ if (err < 0) {
+ PRINTK (KERN_ERR, "IO range already in use!");
+ goto out_disable;
+ }
+
+ dev = kmalloc (sizeof(amb_dev), GFP_KERNEL);
+ if (!dev) {
+ PRINTK (KERN_ERR, "out of memory!");
+ err = -ENOMEM;
+ goto out_release;
+ }
+
+ setup_dev(dev, pci_dev);
+
+ err = amb_init(dev);
+ if (err < 0) {
+ PRINTK (KERN_ERR, "adapter initialisation failure");
+ goto out_free;
+ }
+
+ setup_pci_dev(pci_dev);
+
+ // grab (but share) IRQ and install handler
+ err = request_irq(irq, interrupt_handler, SA_SHIRQ, DEV_LABEL, dev);
+ if (err < 0) {
+ PRINTK (KERN_ERR, "request IRQ failed!");
+ goto out_reset;
+ }
+
+ dev->atm_dev = atm_dev_register (DEV_LABEL, &amb_ops, -1, NULL);
+ if (!dev->atm_dev) {
+ PRINTD (DBG_ERR, "failed to register Madge ATM adapter");
+ err = -EINVAL;
+ goto out_free_irq;
+ }
+
+ PRINTD (DBG_INFO, "registered Madge ATM adapter (no. %d) (%p) at %p",
+ dev->atm_dev->number, dev, dev->atm_dev);
+ dev->atm_dev->dev_data = (void *) dev;
+
+ // register our address
+ amb_esi (dev, dev->atm_dev->esi);
+
+ // 0 bits for vpi, 10 bits for vci
+ dev->atm_dev->ci_range.vpi_bits = NUM_VPI_BITS;
+ dev->atm_dev->ci_range.vci_bits = NUM_VCI_BITS;
+
+ init_timer(&dev->housekeeping);
+ dev->housekeeping.function = do_housekeeping;
+ dev->housekeeping.data = (unsigned long) dev;
+ mod_timer(&dev->housekeeping, jiffies);
+
+ // enable host interrupts
+ interrupts_on (dev);
+
+out:
+ return err;
+
+out_free_irq:
+ free_irq(irq, dev);
+out_reset:
+ amb_reset(dev, 0);
+out_free:
+ kfree(dev);
+out_release:
+ pci_release_region(pci_dev, 1);
+out_disable:
+ pci_disable_device(pci_dev);
+ goto out;
+}
+
+
+static void __devexit amb_remove_one(struct pci_dev *pci_dev)
+{
+ struct amb_dev *dev;
+
+ dev = pci_get_drvdata(pci_dev);
+
+ PRINTD(DBG_INFO|DBG_INIT, "closing %p (atm_dev = %p)", dev, dev->atm_dev);
+ del_timer_sync(&dev->housekeeping);
+ // the drain should not be necessary
+ drain_rx_pools(dev);
+ interrupts_off(dev);
+ amb_reset(dev, 0);
+ free_irq(dev->irq, dev);
+ pci_disable_device(pci_dev);
+ destroy_queues(dev);
+ atm_dev_deregister(dev->atm_dev);
+ kfree(dev);
+ pci_release_region(pci_dev, 1);
+}
+
+static void __init amb_check_args (void) {
+ unsigned char pool;
+ unsigned int max_rx_size;
+
+#ifdef DEBUG_AMBASSADOR
+ PRINTK (KERN_NOTICE, "debug bitmap is %hx", debug &= DBG_MASK);
+#else
+ if (debug)
+ PRINTK (KERN_NOTICE, "no debugging support");
+#endif
+
+ if (cmds < MIN_QUEUE_SIZE)
+ PRINTK (KERN_NOTICE, "cmds has been raised to %u",
+ cmds = MIN_QUEUE_SIZE);
+
+ if (txs < MIN_QUEUE_SIZE)
+ PRINTK (KERN_NOTICE, "txs has been raised to %u",
+ txs = MIN_QUEUE_SIZE);
+
+ for (pool = 0; pool < NUM_RX_POOLS; ++pool)
+ if (rxs[pool] < MIN_QUEUE_SIZE)
+ PRINTK (KERN_NOTICE, "rxs[%hu] has been raised to %u",
+ pool, rxs[pool] = MIN_QUEUE_SIZE);
+
+ // buffers sizes should be greater than zero and strictly increasing
+ max_rx_size = 0;
+ for (pool = 0; pool < NUM_RX_POOLS; ++pool)
+ if (rxs_bs[pool] <= max_rx_size)
+ PRINTK (KERN_NOTICE, "useless pool (rxs_bs[%hu] = %u)",
+ pool, rxs_bs[pool]);
+ else
+ max_rx_size = rxs_bs[pool];
+
+ if (rx_lats < MIN_RX_BUFFERS)
+ PRINTK (KERN_NOTICE, "rx_lats has been raised to %u",
+ rx_lats = MIN_RX_BUFFERS);
+
+ return;
+}
+
+/********** module stuff **********/
+
+MODULE_AUTHOR(maintainer_string);
+MODULE_DESCRIPTION(description_string);
+MODULE_LICENSE("GPL");
+module_param(debug, ushort, 0644);
+module_param(cmds, uint, 0);
+module_param(txs, uint, 0);
+module_param_array(rxs, uint, NULL, 0);
+module_param_array(rxs_bs, uint, NULL, 0);
+module_param(rx_lats, uint, 0);
+module_param(pci_lat, byte, 0);
+MODULE_PARM_DESC(debug, "debug bitmap, see .h file");
+MODULE_PARM_DESC(cmds, "number of command queue entries");
+MODULE_PARM_DESC(txs, "number of TX queue entries");
+MODULE_PARM_DESC(rxs, "number of RX queue entries [" __MODULE_STRING(NUM_RX_POOLS) "]");
+MODULE_PARM_DESC(rxs_bs, "size of RX buffers [" __MODULE_STRING(NUM_RX_POOLS) "]");
+MODULE_PARM_DESC(rx_lats, "number of extra buffers to cope with RX latencies");
+MODULE_PARM_DESC(pci_lat, "PCI latency in bus cycles");
+
+/********** module entry **********/
+
+static struct pci_device_id amb_pci_tbl[] = {
+ { PCI_VENDOR_ID_MADGE, PCI_DEVICE_ID_MADGE_AMBASSADOR, PCI_ANY_ID, PCI_ANY_ID,
+ 0, 0, 0 },
+ { PCI_VENDOR_ID_MADGE, PCI_DEVICE_ID_MADGE_AMBASSADOR_BAD, PCI_ANY_ID, PCI_ANY_ID,
+ 0, 0, 0 },
+ { 0, }
+};
+
+MODULE_DEVICE_TABLE(pci, amb_pci_tbl);
+
+static struct pci_driver amb_driver = {
+ .name = "amb",
+ .probe = amb_probe,
+ .remove = __devexit_p(amb_remove_one),
+ .id_table = amb_pci_tbl,
+};
+
+static int __init amb_module_init (void)
+{
+ PRINTD (DBG_FLOW|DBG_INIT, "init_module");
+
+ // sanity check - cast needed as printk does not support %Zu
+ if (sizeof(amb_mem) != 4*16 + 4*12) {
+ PRINTK (KERN_ERR, "Fix amb_mem (is %lu words).",
+ (unsigned long) sizeof(amb_mem));
+ return -ENOMEM;
+ }
+
+ show_version();
+
+ amb_check_args();
+
+ // get the juice
+ return pci_register_driver(&amb_driver);
+}
+
+/********** module exit **********/
+
+static void __exit amb_module_exit (void)
+{
+ PRINTD (DBG_FLOW|DBG_INIT, "cleanup_module");
+
+ return pci_unregister_driver(&amb_driver);
+}
+
+module_init(amb_module_init);
+module_exit(amb_module_exit);