Re: [PATCH 2/3] Import fw-ohci driver.

Jeff Garzik
2006-12-05T05:58:42Z

Kristian Høgsberg wrote:
> Add the OHCI driver to the stack and build system.
>
> Signed-off-by: Kristian Høgsberg <krh@redhat.com>
> ---
>
> drivers/fw/fw-ohci.c | 1334 ++++++++++++++++++++++++++++++++++++++++++++++++++
> drivers/fw/fw-ohci.h | 152 ++++++
> 2 files changed, 1486 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/fw/fw-ohci.c b/drivers/fw/fw-ohci.c
> new file mode 100644
> index 0000000..78e0324
> --- /dev/null
> +++ b/drivers/fw/fw-ohci.c
> @@ -0,0 +1,1334 @@
> +/* -*- c-basic-offset: 8 -*-
> + *
> + * fw-ohci.c - Driver for OHCI 1394 boards
> + * Copyright (C) 2003 Kristian Høgsberg <krh@bitplanet.net>
> + *
> + * 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.
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/init.h>
> +#include <linux/interrupt.h>
> +#include <linux/pci.h>
> +#include <linux/delay.h>
> +#include <linux/poll.h>
> +#include <asm/uaccess.h>
> +#include <asm/semaphore.h>
> +
> +#include "fw-transaction.h"
> +#include "fw-ohci.h"
> +
> +struct descriptor {
> + u32 req_count:16;
> +
> + u32 wait:2;
> + u32 branch:2;
> + u32 irq:2;
> + u32 yy:1;
> + u32 ping:1;
> +
> + u32 key:3;
> + u32 status:1;
> + u32 command:4;
> +
> + u32 data_address;
> + u32 branch_address;
> +
> + u32 res_count:16;
> + u32 transfer_status:16;
> +} __attribute__ ((aligned(16)));

you probably want __le32 annotations for sparse, right?

> +#define DESCRIPTOR_OUTPUT_MORE 0
> +#define DESCRIPTOR_OUTPUT_LAST 1
> +#define DESCRIPTOR_INPUT_MORE 2
> +#define DESCRIPTOR_INPUT_LAST 3
> +#define DESCRIPTOR_NO_IRQ 0
> +#define DESCRIPTOR_IRQ_ERROR 1
> +#define DESCRIPTOR_IRQ_ALWAYS 3
> +#define DESCRIPTOR_KEY_IMMEDIATE 2
> +#define DESCRIPTOR_BRANCH_ALWAYS 3
> +
> +struct ar_context {
> + struct fw_ohci *ohci;
> + struct descriptor descriptor;
> + u32 buffer[512];
> + dma_addr_t descriptor_bus;
> + dma_addr_t buffer_bus;
> +
> + u32 command_ptr;
> + u32 control_set;
> + u32 control_clear;
> +
> + struct tasklet_struct tasklet;
> +};
> +
> +struct at_context {
> + struct fw_ohci *ohci;
> + dma_addr_t descriptor_bus;
> + dma_addr_t buffer_bus;
> +
> + struct list_head list;
> +
> + struct {
> + struct descriptor more;
> + u32 header[4];
> + struct descriptor last;
> + } descriptor;
> +
> + u32 command_ptr;
> + u32 control_set;
> + u32 control_clear;
> +
> + struct tasklet_struct tasklet;
> +};
> +
> +struct it_header {
> + u32 sy:4;
> + u32 tcode:4;
> + u32 channel:6;
> + u32 tag:2;
> + u32 speed:3;
> + u32 reserved0:13;
> + u32 reserved1:16;
> + u32 data_length:16;
> +};

ditto.

And for the last two fields, I bet that using the normal 'u16' type
(__le16?) would generate much better code than a bitfield:16 ever would.

> +struct iso_context {
> + struct fw_iso_context base;
> + struct tasklet_struct tasklet;
> + u32 control_set;
> + u32 control_clear;
> + u32 command_ptr;
> + u32 context_match;
> +
> + struct descriptor *buffer;
> + dma_addr_t buffer_bus;
> + struct descriptor *head_descriptor;
> + struct descriptor *tail_descriptor;
> + struct descriptor *tail_descriptor_last;
> + struct descriptor *prev_descriptor;
> +};
> +
> +#define CONFIG_ROM_SIZE 1024
> +
> +struct fw_ohci {
> + struct fw_card card;
> +
> + struct pci_dev *dev;

struct device* instead? grep for to_pci_dev() to see how to get pci-dev
from device.

> + char *registers;

should be 'void __iomem *'

See Documentation/sparse.txt for more info on checking your code with
sparse.

> + dma_addr_t self_id_bus;
> + u32 *self_id_cpu;
> + struct tasklet_struct bus_reset_tasklet;
> + int generation;
> + int request_generation;
> +
> + spinlock_t lock;
> + u32 self_id_buffer[512];
> +
> + /* Config rom buffers */
> + u32 *config_rom;
> + dma_addr_t config_rom_bus;
> + u32 *next_config_rom;
> + dma_addr_t next_config_rom_bus;
> +
> + struct ar_context ar_request_ctx;
> + struct ar_context ar_response_ctx;
> + struct at_context at_request_ctx;
> + struct at_context at_response_ctx;
> +
> + u32 it_context_mask;
> + struct iso_context *it_context_list;
> + u32 ir_context_mask;
> + struct iso_context *ir_context_list;
> +};
> +
> +extern inline struct fw_ohci *fw_ohci(struct fw_card *card)
> +{
> + return container_of(card, struct fw_ohci, card);
> +}
> +
> +#define CONTEXT_CYCLE_MATCH_ENABLE 0x80000000
> +
> +#define CONTEXT_RUN 0x8000
> +#define CONTEXT_WAKE 0x1000
> +#define CONTEXT_DEAD 0x0800
> +#define CONTEXT_ACTIVE 0x0400
> +
> +#define OHCI1394_MAX_AT_REQ_RETRIES 0x2
> +#define OHCI1394_MAX_AT_RESP_RETRIES 0x2
> +#define OHCI1394_MAX_PHYS_RESP_RETRIES 0x8
> +
> +#define FW_OHCI_MAJOR 240
> +#define OHCI1394_REGISTER_SIZE 0x800
> +#define OHCI_LOOP_COUNT 500
> +#define OHCI1394_PCI_HCI_Control 0x40
> +#define SELF_ID_BUF_SIZE 0x800

consider using

enum {
constant1 = 1234,
constant2 = 5678,
};

for constants. These actually have some type information attached by
the compiler, and they show up as symbols in the debugger since they are
not stripped out by the C pre-processor.

> +#define PCI_CLASS_FIREWIRE_OHCI ((PCI_CLASS_SERIAL_FIREWIRE << 8) | 0x10)
> +
> +static char ohci_driver_name[] = KBUILD_MODNAME;
> +
> +extern inline void reg_write(const struct fw_ohci *ohci, int offset, u32 data)
> +{
> + writel(data, ohci->registers + offset);
> +}
> +
> +extern inline u32 reg_read(const struct fw_ohci *ohci, int offset)
> +{
> + return readl(ohci->registers + offset);
> +}
> +
> +static int read_phy_reg(struct fw_ohci *ohci, u8 addr)
> +{
> + u32 val;
> +
> + reg_write(ohci, OHCI1394_PhyControl, OHCI1394_PhyControl_Read(addr));
> + msleep(2);
> + val = reg_read(ohci, OHCI1394_PhyControl);
> + if ((val & OHCI1394_PhyControl_ReadDone) == 0)
> + return -EBUSY;
> +
> + return OHCI1394_PhyControl_ReadData(val);
> +}
> +
> +static void write_phy_reg(struct fw_ohci *ohci, u8 addr, u8 data)
> +{
> + reg_write(ohci, OHCI1394_PhyControl,
> + OHCI1394_PhyControl_Write(addr, data));
> +}
> +
> +static int
> +ohci_update_phy_reg(struct fw_card *card, int addr,
> + int clear_bits, int set_bits)
> +{
> + struct fw_ohci *ohci = fw_ohci(card);
> + int old;
> +
> + old = read_phy_reg(ohci, addr);
> + if (old < 0) {
> + fw_error("failed to set phy reg bits.\n");
> + return old;
> + }
> + old = (old & ~clear_bits) | set_bits;
> + write_phy_reg(ohci, addr, old);
> +
> + return 0;
> +}
> +
> +static void ar_context_run(struct ar_context *ctx)
> +{
> + reg_write(ctx->ohci, ctx->command_ptr, ctx->descriptor_bus | 1);
> + reg_write(ctx->ohci, ctx->control_set, CONTEXT_RUN);

PCI posting?

> +static void ar_context_tasklet(unsigned long data)
> +{
> + struct ar_context *ctx = (struct ar_context *)data;
> + struct fw_ohci *ohci = ctx->ohci;
> + u32 status;
> + int length, speed, ack, timestamp;
> +
> + /* FIXME: What to do about evt_* errors? */
> + length = ctx->descriptor.req_count - ctx->descriptor.res_count - 4;
> + status = ctx->buffer[length / 4];
> + ack = ((status >> 16) & 0x1f) - 16;
> + speed = (status >> 21) & 0x7;
> + timestamp = status & 0xffff;
> +
> + /* The OHCI bus reset handler synthesizes a phy packet with
> + * the new generation number when a bus reset happens (see
> + * section 8.4.2.3). This helps us determine when a request
> + * was received and make sure we send the response in the same
> + * generation. We only need this for requests; for responses
> + * we use the unique tlabel for finding the matching
> + * request. */
> + if (ack + 16 == 0x09)
> + ohci->request_generation = (ctx->buffer[2] >> 16) & 0xff;
> + else if (ctx == &ohci->ar_request_ctx)
> + fw_core_handle_request(&ohci->card, speed, ack, timestamp,
> + ohci->request_generation,
> + length, ctx->buffer);
> + else
> + fw_core_handle_response(&ohci->card, speed, ack, timestamp,
> + length, ctx->buffer);
> +
> + ctx->descriptor.data_address = ctx->buffer_bus;
> + ctx->descriptor.req_count = sizeof ctx->buffer;
> + ctx->descriptor.res_count = ctx->descriptor.req_count;
> +
> + dma_sync_single_for_device(&ohci->dev->dev, ctx->descriptor_bus,
> + sizeof ctx->descriptor_bus, DMA_TO_DEVICE);
> +
> + /* FIXME: We stop and restart the ar context here, what if we
> + * stop while a receive is in progress? Maybe we could just
> + * loop the context back to itself and use it in buffer fill
> + * mode as intended... */
> +
> + reg_write(ctx->ohci, ctx->control_clear, CONTEXT_RUN);
> + ar_context_run(ctx);
> +}
> +
> +static int
> +ar_context_init(struct ar_context *ctx, struct fw_ohci *ohci, u32 control_set)
> +{
> + /* FIXME: cpu_to_le32. */
> +
> + ctx->descriptor_bus =
> + dma_map_single(&ohci->dev->dev, &ctx->descriptor,
> + sizeof ctx->descriptor, PCI_DMA_TODEVICE);
> + if (ctx->descriptor_bus == 0)
> + return -ENOMEM;
> +
> + if (ctx->descriptor_bus & 0xf)
> + fw_notify("descriptor not 16-byte aligned: 0x%08x\n",
> + ctx->descriptor_bus);
> +
> + ctx->buffer_bus =
> + dma_map_single(&ohci->dev->dev, ctx->buffer,
> + sizeof ctx->buffer, PCI_DMA_FROMDEVICE);
> +
> + if (ctx->buffer_bus == 0)
> + return -ENOMEM;

leak on error

> + memset(&ctx->descriptor, 0, sizeof ctx->descriptor);
> + ctx->descriptor.command = DESCRIPTOR_INPUT_MORE;
> + ctx->descriptor.status = 1;
> + ctx->descriptor.irq = DESCRIPTOR_NO_IRQ;
> + ctx->descriptor.branch = DESCRIPTOR_BRANCH_ALWAYS;
> + ctx->descriptor.req_count = sizeof ctx->buffer;
> + ctx->descriptor.data_address = ctx->buffer_bus;
> + ctx->descriptor.res_count = ctx->descriptor.req_count;
> +
> + ctx->control_set = control_set;
> + ctx->control_clear = control_set + 4;
> + ctx->command_ptr = control_set + 12;
> + ctx->ohci = ohci;
> +
> + tasklet_init(&ctx->tasklet, ar_context_tasklet, (unsigned long)ctx);
> +
> + ar_context_run(ctx);
> +
> + return 0;
> +}
> +
> + ohci->next_config_rom = NULL;
> + }
> +
> + spin_unlock_irqrestore(&ohci->lock, flags);
> +
> + fw_core_handle_bus_reset(&ohci->card, node_id, generation,
> + self_id_count, ohci->self_id_buffer);
> +}
> +
> +static irqreturn_t irq_handler(int irq, void *data, struct pt_regs *unused)
> +{
> + struct fw_ohci *ohci = data;
> + u32 event, iso_event;
> + int i;
> +
> + event = reg_read(ohci, OHCI1394_IntEventClear);
> +
> + if (!event)
> + return IRQ_NONE;

check for 0xffffffff also

> + reg_write(ohci, OHCI1394_IntEventClear, event);
> +
> + if (event & OHCI1394_selfIDComplete)
> + tasklet_schedule(&ohci->bus_reset_tasklet);
> +
> + if (event & OHCI1394_RQPkt)
> + tasklet_schedule(&ohci->ar_request_ctx.tasklet);
> +
> + if (event & OHCI1394_RSPkt)
> + tasklet_schedule(&ohci->ar_response_ctx.tasklet);
> +
> + if (event & OHCI1394_reqTxComplete)
> + tasklet_schedule(&ohci->at_request_ctx.tasklet);
> +
> + if (event & OHCI1394_respTxComplete)
> + tasklet_schedule(&ohci->at_response_ctx.tasklet);
> +
> + iso_event = reg_read(ohci, OHCI1394_IsoRecvIntEventSet);
> + reg_write(ohci, OHCI1394_IsoRecvIntEventClear, iso_event);
> +
> + while (iso_event) {
> + i = ffs(iso_event) - 1;
> + tasklet_schedule(&ohci->ir_context_list[i].tasklet);
> + iso_event &= ~(1 << i);
> + }
> +
> + iso_event = reg_read(ohci, OHCI1394_IsoXmitIntEventSet);
> + reg_write(ohci, OHCI1394_IsoXmitIntEventClear, iso_event);
> +
> + while (iso_event) {
> + i = ffs(iso_event) - 1;
> + tasklet_schedule(&ohci->it_context_list[i].tasklet);
> + iso_event &= ~(1 << i);
> + }
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int ohci_enable(struct fw_card *card, u32 * config_rom, size_t length)
> +{
> + struct fw_ohci *ohci = fw_ohci(card);
> +
> + /* When the link is not yet enabled, the atomic config rom
> + * described above is not active. We have to update
> + * ConfigRomHeader and BusOptions manually, and the write to
> + * ConfigROMmap takes effect immediately. We tie this to the
> + * enabling of the link, so we ensure that we have a valid
> + * config rom before enabling - the OHCI requires that
> + * ConfigROMhdr and BusOptions have valid values before
> + * enabling.
> + */
> +
> + ohci->config_rom = pci_alloc_consistent(ohci->dev, CONFIG_ROM_SIZE,
> + &ohci->config_rom_bus);
> + if (ohci->config_rom == NULL)
> + return -ENOMEM;
> +
> + memset(ohci->config_rom, 0, CONFIG_ROM_SIZE);
> + fw_memcpy_to_be32(ohci->config_rom, config_rom, length * 4);
> +
> + reg_write(ohci, OHCI1394_ConfigROMmap, ohci->config_rom_bus);
> + reg_write(ohci, OHCI1394_ConfigROMhdr, config_rom[0]);
> + reg_write(ohci, OHCI1394_BusOptions, config_rom[2]);
> +
> + reg_write(ohci, OHCI1394_AsReqFilterHiSet, 0x80000000);
> +
> + if (request_irq(ohci->dev->irq, irq_handler,
> + SA_SHIRQ, ohci_driver_name, ohci)) {
> + fw_error("Failed to allocate shared interrupt %d.\n",
> + ohci->dev->irq);
> + return -EIO;

leak on error

> + reg_write(ohci, OHCI1394_HCControlSet,
> + OHCI1394_HCControl_linkEnable |
> + OHCI1394_HCControl_BIBimageValid);

PCI posting

> + /* We are ready to go, initiate bus reset to finish the
> + * initialization. */
> +
> + fw_core_initiate_bus_reset(&ohci->card, 1);
> +
> + return 0;
> +}
> +
> +static int
> +ohci_set_config_rom(struct fw_card *card, u32 * config_rom, size_t length)
> +{
> + struct fw_ohci *ohci;
> + unsigned long flags;
> + int retval = 0;
> +
> + ohci = fw_ohci(card);
> +
> + /* When the OHCI controller is enabled, the config rom update
> + * mechanism is a bit tricky, but easy enough to use. See
> + * section 5.5.6 in the OHCI specification.
> + *
> + * The OHCI controller caches the new config rom address in a
> + * shadow register (ConfigROMmapNext) and needs a bus reset
> + * for the changes to take place. When the bus reset is
> + * detected, the controller loads the new values for the
> + * ConfigRomHeader and BusOptions registers from the specified
> + * config rom and loads ConfigROMmap from the ConfigROMmapNext
> + * shadow register. All automatically and atomically.
> + *
> + * We use ohci->lock to avoid racing with the code that sets
> + * ohci->next_config_rom to NULL (see bus_reset_tasklet).
> + */
> +
> + spin_lock_irqsave(&ohci->lock, flags);
> +
> + if (ohci->next_config_rom == NULL) {
> + ohci->next_config_rom =
> + pci_alloc_consistent(ohci->dev, CONFIG_ROM_SIZE,
> + &ohci->next_config_rom_bus);
> +
> + memset(ohci->next_config_rom, 0, CONFIG_ROM_SIZE);

next_config_rom could be NULL. you have got to check allocations inside
spinlocks (GFP_ATOMIC), they are more likely to fail than GFP_KERNEL.

> + fw_memcpy_to_be32(ohci->next_config_rom, config_rom,
> + length * 4);
> + reg_write(ohci, OHCI1394_ConfigROMmap,
> + ohci->next_config_rom_bus);
> +
> + /* Now initiate a bus reset to have the changes take
> + * effect. We clean up the old config rom memory and
> + * DMA mappings in the bus reset tasklet, since the
> + * OHCI controller could need to access it before the
> + * bus reset takes effect.
> + */
> +
> + fw_core_initiate_bus_reset(&ohci->card, 1);
> + } else
> + retval = -EBUSY;
> +
> + spin_unlock_irqrestore(&ohci->lock, flags);
> +
> + return retval;
> +}
> +
> +static void ohci_send_request(struct fw_card *card, struct fw_packet *packet)
> +{
> + struct fw_ohci *ohci = fw_ohci(card);
> +
> + at_context_transmit(&ohci->at_request_ctx, packet);
> +}
> +
> +static void ohci_send_response(struct fw_card *card, struct fw_packet *packet)
> +{
> + struct fw_ohci *ohci = fw_ohci(card);
> +
> + at_context_transmit(&ohci->at_response_ctx, packet);
> +}
> +
> +static int
> +ohci_enable_phys_dma(struct fw_card *card, int node_id, int generation)
> +{
> + struct fw_ohci *ohci = fw_ohci(card);
> + unsigned long flags;
> + int retval = 0;
> +
> + /* FIXME: make sure this bitmask is cleared when we clear the
> + * busReset interrupt bit. */
> +
> + spin_lock_irqsave(&ohci->lock, flags);
> +
> + if (ohci->generation != generation) {
> + retval = -ESTALE;
> + goto out;
> + }
> +
> + if (node_id < 32) {
> + reg_write(ohci, OHCI1394_PhyReqFilterLoSet, 1 << node_id);
> + } else {
> + reg_write(ohci, OHCI1394_PhyReqFilterHiSet,
> + 1 << (node_id - 32));
> + }

PCI posting

> + spin_unlock_irqrestore(&ohci->lock, flags);
> +
> + out:
> + return retval;
> +}
> +
> +static void ir_context_tasklet(unsigned long data)
> +{
> + struct iso_context *ctx = (struct iso_context *)data;
> +
> + (void)ctx;
> +}
> +
> +#define ISO_BUFFER_SIZE (64 * 1024)
> +
> +static void flush_iso_context(struct iso_context *ctx)
> +{
> + struct fw_ohci *ohci = fw_ohci(ctx->base.card);
> + struct descriptor *d, *last;
> + int z;
> +
> + dma_sync_single_for_cpu(ohci->card.device, ctx->buffer_bus,
> + ISO_BUFFER_SIZE, DMA_TO_DEVICE);
> +
> + d = ctx->tail_descriptor;
> + last = ctx->tail_descriptor_last;
> +
> + while (last->branch_address != 0 && last->transfer_status != 0) {
> + z = last->branch_address & 0xf;
> + d = ctx->buffer + (last->branch_address -
> + ctx->buffer_bus) / sizeof *d;
> +
> + if (z == 2)
> + last = d;
> + else
> + last = d + z - 1;
> +
> + if (last->irq)
> + ctx->base.callback(&ctx->base,
> + 0, last->res_count,
> + ctx->base.callback_data);
> + }
> +
> + ctx->tail_descriptor = d;
> + ctx->tail_descriptor_last = last;
> +}
> +
> +static void it_context_tasklet(unsigned long data)
> +{
> + struct iso_context *ctx = (struct iso_context *)data;
> +
> + flush_iso_context(ctx);
> +}
> +
> +static struct fw_iso_context *ohci_allocate_iso_context(struct fw_card *card,
> + int type)
> +{
> + struct fw_ohci *ohci = fw_ohci(card);
> + struct iso_context *ctx, *list;
> + void (*tasklet) (unsigned long data);
> + u32 *mask;
> + unsigned long flags;
> + int index;
> +
> + if (type == FW_ISO_CONTEXT_TRANSMIT) {
> + mask = &ohci->it_context_mask;
> + list = ohci->it_context_list;
> + tasklet = it_context_tasklet;
> + } else {
> + mask = &ohci->ir_context_mask;
> + list = ohci->ir_context_list;
> + tasklet = ir_context_tasklet;
> + }
> +
> + spin_lock_irqsave(&ohci->lock, flags);
> + index = ffs(*mask) - 1;
> + if (index >= 0)
> + *mask &= ~(1 << index);
> + spin_unlock_irqrestore(&ohci->lock, flags);
> +
> + if (index < 0)
> + return ERR_PTR(-EBUSY);
> +
> + ctx = &list[index];
> + memset(ctx, 0, sizeof *ctx);
> + tasklet_init(&ctx->tasklet, tasklet, (unsigned long)ctx);
> +
> + ctx->buffer = kmalloc(ISO_BUFFER_SIZE, GFP_KERNEL);
> + if (ctx->buffer == NULL) {
> + spin_lock_irqsave(&ohci->lock, flags);
> + *mask |= 1 << index;
> + spin_unlock_irqrestore(&ohci->lock, flags);
> + return ERR_PTR(-ENOMEM);
> + }
> +
> + ctx->buffer_bus =
> + dma_map_single(card->device, ctx->buffer,
> + ISO_BUFFER_SIZE, PCI_DMA_TODEVICE);
> +
> + ctx->head_descriptor = ctx->buffer;
> + ctx->prev_descriptor = ctx->buffer;
> + ctx->tail_descriptor = ctx->buffer;
> + ctx->tail_descriptor_last = ctx->buffer;
> +
> + /* We put a dummy descriptor in the buffer that has a NULL
> + * branch address and looks like it's been sent. That way we
> + * have a descriptor to append DMA programs to. Also, the
> + * ring buffer invariant is that it always has at least one
> + * element so that head == tail means buffer full. */
> +
> + memset(ctx->head_descriptor, 0, sizeof *ctx->head_descriptor);
> + ctx->head_descriptor->command = DESCRIPTOR_OUTPUT_LAST;
> + ctx->head_descriptor->transfer_status = 0x8011;
> + ctx->head_descriptor++;
> +
> + return &ctx->base;
> +}
> +
> +static int ohci_send_iso(struct fw_iso_context *base, s32 cycle)
> +{
> + struct iso_context *ctx = (struct iso_context *)base;
> + struct fw_ohci *ohci = fw_ohci(ctx->base.card);
> + u32 cycle_match = 0;
> + int index;
> +
> + index = ctx - ohci->it_context_list;
> + if (cycle > 0)
> + cycle_match = CONTEXT_CYCLE_MATCH_ENABLE |
> + (cycle & 0x7fff) << 16;
> +
> + reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, 1 << index);
> + reg_write(ohci, OHCI1394_IsoXmitCommandPtr(index),
> + ctx->tail_descriptor_last->branch_address);
> + reg_write(ohci, OHCI1394_IsoXmitContextControlClear(index), ~0);
> + reg_write(ohci, OHCI1394_IsoXmitContextControlSet(index),
> + CONTEXT_RUN | cycle_match);

PCI posting?

> +static void ohci_free_iso_context(struct fw_iso_context *base)
> +{
> + struct fw_ohci *ohci = fw_ohci(base->card);
> + struct iso_context *ctx = (struct iso_context *)base;
> + unsigned long flags;
> + int index;
> +
> + flush_iso_context(ctx);
> +
> + spin_lock_irqsave(&ohci->lock, flags);
> +
> + if (ctx->base.type == FW_ISO_CONTEXT_TRANSMIT) {
> + index = ctx - ohci->it_context_list;
> + reg_write(ohci, OHCI1394_IsoXmitContextControlClear(index), ~0);
> + reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, 1 << index);
> + ohci->it_context_mask |= 1 << index;
> + } else {
> + index = ctx - ohci->ir_context_list;
> + reg_write(ohci, OHCI1394_IsoRcvContextControlClear(index), ~0);
> + reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, 1 << index);
> + ohci->ir_context_mask |= 1 << index;
> + }
> +
> + dma_unmap_single(ohci->card.device, ctx->buffer_bus,
> + ISO_BUFFER_SIZE, DMA_TO_DEVICE);

PCI posting?

> + spin_unlock_irqrestore(&ohci->lock, flags);
> +}
> +
> +static int
> +ohci_queue_iso(struct fw_iso_context *base,
> + struct fw_iso_packet *packet, void *payload)
> +{
> + struct iso_context *ctx = (struct iso_context *)base;
> + struct fw_ohci *ohci = fw_ohci(ctx->base.card);
> + struct descriptor *d, *end, *last, *tail, *pd;
> + struct fw_iso_packet *p;
> + struct it_header *header;
> + dma_addr_t d_bus;
> + u32 z, header_z, payload_z;
> + u32 payload_index, payload_end_index, next_page_index;
> + int index, page, end_page, i, length, offset;
> +
> + /* FIXME: Cycle lost behavior should be configurable: lose
> + * packet, retransmit or terminate.. */
> +
> + p = packet;
> + payload_index = payload - ctx->base.buffer;
> + d = ctx->head_descriptor;
> + tail = ctx->tail_descriptor;
> + end = ctx->buffer + ISO_BUFFER_SIZE / sizeof(struct descriptor);
> +
> + if (p->skip)
> + z = 1;
> + else
> + z = 2;
> + if (p->header_length > 0)
> + z++;
> +
> + /* Determine the first page the payload isn't contained in. */
> + end_page = PAGE_ALIGN(payload_index + p->payload_length) >> PAGE_SHIFT;
> + if (p->payload_length > 0)
> + payload_z = end_page - (payload_index >> PAGE_SHIFT);
> + else
> + payload_z = 0;
> +
> + z += payload_z;
> +
> + /* Get header size in number of descriptors. */
> + header_z = DIV_ROUND_UP(p->header_length, sizeof *d);
> +
> + if (d + z + header_z <= tail) {
> + goto has_space;
> + } else if (d > tail && d + z + header_z <= end) {
> + goto has_space;
> + } else if (d > tail && ctx->buffer + z + header_z <= tail) {
> + d = ctx->buffer;
> + goto has_space;
> + }
> +
> + /* No space in buffer */
> + return -1;
> +
> + has_space:
> + memset(d, 0, (z + header_z) * sizeof *d);
> + d_bus = ctx->buffer_bus + (d - ctx->buffer) * sizeof *d;
> +
> + if (p->skip) {
> + d[0].key = 0;
> + d[0].req_count = 0;
> + } else {
> + d[0].key = DESCRIPTOR_KEY_IMMEDIATE;
> + d[0].req_count = 8;
> +
> + header = (struct it_header *)&d[1];
> + header->sy = p->sy;
> + header->tag = p->tag;
> + header->tcode = TCODE_STREAM_DATA;
> + header->channel = ctx->base.channel;
> + header->speed = ctx->base.speed;
> + header->data_length = p->header_length + p->payload_length;
> + }
> +
> + if (p->header_length > 0) {
> + d[2].req_count = p->header_length;
> + d[2].data_address = d_bus + z * sizeof *d;
> + memcpy(&d[z], p->header, p->header_length);
> + }
> +
> + pd = d + z - payload_z;
> + payload_end_index = payload_index + p->payload_length;
> + for (i = 0; i < payload_z; i++) {
> + page = payload_index >> PAGE_SHIFT;
> + offset = payload_index & ~PAGE_MASK;
> + next_page_index = (page + 1) << PAGE_SHIFT;
> + length =
> + min(next_page_index, payload_end_index) - payload_index;
> + pd[i].req_count = length;
> + pd[i].data_address = ctx->base.pages[page] + offset;
> +
> + payload_index += length;
> + }
> +
> + if (z == 2)
> + last = d;
> + else
> + last = d + z - 1;
> +
> + last->command = DESCRIPTOR_OUTPUT_LAST;
> + last->status = 1;
> + last->branch = DESCRIPTOR_BRANCH_ALWAYS;
> + if (p->interrupt)
> + last->irq = DESCRIPTOR_IRQ_ALWAYS;
> + else
> + last->irq = DESCRIPTOR_NO_IRQ;
> +
> + dma_sync_single_for_device(ohci->card.device, ctx->buffer_bus,
> + ISO_BUFFER_SIZE, DMA_TO_DEVICE);
> +
> + ctx->head_descriptor = d + z + header_z;
> + ctx->prev_descriptor->branch_address = d_bus | z;
> + ctx->prev_descriptor = last;
> +
> + index = ctx - ohci->it_context_list;
> + reg_write(ohci, OHCI1394_IsoXmitContextControlSet(index), CONTEXT_WAKE);

PCI posting?

> +static struct fw_card_driver ohci_driver = {
> + .name = ohci_driver_name,
> + .enable = ohci_enable,
> + .update_phy_reg = ohci_update_phy_reg,
> + .set_config_rom = ohci_set_config_rom,
> + .send_request = ohci_send_request,
> + .send_response = ohci_send_response,
> + .enable_phys_dma = ohci_enable_phys_dma,
> +
> + .allocate_iso_context = ohci_allocate_iso_context,
> + .free_iso_context = ohci_free_iso_context,
> + .queue_iso = ohci_queue_iso,
> + .send_iso = ohci_send_iso
> +};
> +
> +static int software_reset(struct fw_ohci *ohci)
> +{
> + int i;
> +
> + reg_write(ohci, OHCI1394_HCControlSet, OHCI1394_HCControl_softReset);
> +
> + for (i = 0; i < OHCI_LOOP_COUNT; i++) {
> + if ((reg_read(ohci, OHCI1394_HCControlSet) &
> + OHCI1394_HCControl_softReset) == 0)
> + return 0;
> + msleep(1);
> + }
> +
> + return -EBUSY;
> +}
> +
> +/* ---------- pci subsystem interface ---------- */
> +
> +enum {
> + CLEANUP_IRQ,
> + CLEANUP_SELF_ID,
> + CLEANUP_REGISTERS,
> + CLEANUP_IOMEM,
> + CLEANUP_OHCI
> +};
> +
> +static int cleanup(struct fw_ohci *ohci, int stage, int code)
> +{
> + switch (stage) {
> + case CLEANUP_SELF_ID:
> + pci_free_consistent(ohci->dev, SELF_ID_BUF_SIZE,
> + ohci->self_id_cpu, ohci->self_id_bus);
> + case CLEANUP_REGISTERS:
> + kfree(ohci->it_context_list);
> + kfree(ohci->ir_context_list);
> + iounmap(ohci->registers);
> + case CLEANUP_IOMEM:
> + release_mem_region(pci_resource_start(ohci->dev, 0),
> + OHCI1394_REGISTER_SIZE);
> + case CLEANUP_OHCI:
> + fw_card_put(&ohci->card);
> + }
> +
> + return code;
> +}
> +
> +static int __devinit
> +pci_probe(struct pci_dev *dev, const struct pci_device_id *ent)
> +{
> + struct fw_ohci *ohci;
> + u32 base, bus_options, max_receive, link_speed;
> + u64 guid;
> + int error_code;
> + size_t size;
> +
> + if (pci_enable_device(dev)) {
> + fw_error("Failed to enable OHCI hardware.\n");
> + return -ENXIO;
> + }
> +
> + ohci = kzalloc(sizeof *ohci, SLAB_KERNEL);

GFP_KERNEL

> + if (ohci == NULL) {
> + fw_error("Could not malloc fw_ohci data.\n");
> + return -ENOMEM;
> + }
> +
> + pci_set_master(dev);
> + pci_write_config_dword(dev, OHCI1394_PCI_HCI_Control, 0);
> + pci_set_drvdata(dev, ohci);
> +
> + ohci->dev = dev;
> + spin_lock_init(&ohci->lock);
> +
> + tasklet_init(&ohci->bus_reset_tasklet,
> + bus_reset_tasklet, (unsigned long)ohci);
> +
> + /* We hardcode the register set size, since some cards get
> + * this wrong and others have some extra registers after the
> + * OHCI range. We only use the OHCI registers, so there's no
> + * need to be clever. */
> + base = pci_resource_start(dev, 0);
> + if (!request_mem_region(base, OHCI1394_REGISTER_SIZE, ohci_driver_name)) {

ugh! use pci_request_regions(), not request_mem_region()

> + fw_error("MMIO resource (0x%x - 0x%x) unavailable\n",
> + base, base + OHCI1394_REGISTER_SIZE);
> + return cleanup(ohci, CLEANUP_OHCI, -EBUSY);
> + }
> +
> + ohci->registers = ioremap(base, OHCI1394_REGISTER_SIZE);
> + if (ohci->registers == NULL) {
> + fw_error("Failed to remap registers\n");
> + return cleanup(ohci, CLEANUP_IOMEM, -ENXIO);
> + }

pci_iomap() does a lot of this

> + if (software_reset(ohci)) {
> + fw_error("Failed to reset ohci card.\n");
> + return cleanup(ohci, CLEANUP_REGISTERS, -EBUSY);
> + }
> +
> + /* Now enable LPS, which we need in order to start accessing
> + * most of the registers. In fact, on some cards (ALI M5251),
> + * accessing registers in the SClk domain without LPS enabled
> + * will lock up the machine. Wait 50msec to make sure we have
> + * full link enabled. */
> + reg_write(ohci, OHCI1394_HCControlSet,
> + OHCI1394_HCControl_LPS |
> + OHCI1394_HCControl_postedWriteEnable);
> + msleep(50);

PCI posting

> + /* self-id dma buffer allocation */
> + ohci->self_id_cpu = pci_alloc_consistent(ohci->dev, SELF_ID_BUF_SIZE,
> + &ohci->self_id_bus);
> + if (ohci->self_id_cpu == NULL) {
> + fw_error("Out of memory for self ID buffer.\n");
> + return cleanup(ohci, CLEANUP_REGISTERS, -ENOMEM);
> + }
> + reg_write(ohci, OHCI1394_SelfIDBuffer, ohci->self_id_bus);
> + reg_write(ohci, OHCI1394_LinkControlSet,
> + OHCI1394_LinkControl_rcvSelfID |
> + OHCI1394_LinkControl_cycleTimerEnable |
> + OHCI1394_LinkControl_cycleMaster);
> +
> + ar_context_init(&ohci->ar_request_ctx, ohci,
> + OHCI1394_AsReqRcvContextControlSet);
> +
> + ar_context_init(&ohci->ar_response_ctx, ohci,
> + OHCI1394_AsRspRcvContextControlSet);
> +
> + at_context_init(&ohci->at_request_ctx, ohci,
> + OHCI1394_AsReqTrContextControlSet);
> +
> + at_context_init(&ohci->at_response_ctx, ohci,
> + OHCI1394_AsRspTrContextControlSet);
> +
> + reg_write(ohci, OHCI1394_ATRetries,
> + OHCI1394_MAX_AT_REQ_RETRIES |
> + (OHCI1394_MAX_AT_RESP_RETRIES << 4) |
> + (OHCI1394_MAX_PHYS_RESP_RETRIES << 8));
> +
> + reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, ~0);
> + ohci->it_context_mask = reg_read(ohci, OHCI1394_IsoRecvIntMaskSet);
> + reg_write(ohci, OHCI1394_IsoRecvIntMaskClear, ~0);
> + size = sizeof(struct iso_context) * hweight32(ohci->it_context_mask);
> + ohci->it_context_list = kzalloc(size, GFP_KERNEL);
> +
> + reg_write(ohci, OHCI1394_IsoXmitIntMaskSet, ~0);
> + ohci->ir_context_mask = reg_read(ohci, OHCI1394_IsoXmitIntMaskSet);
> + reg_write(ohci, OHCI1394_IsoXmitIntMaskClear, ~0);
> + size = sizeof(struct iso_context) * hweight32(ohci->ir_context_mask);
> + ohci->ir_context_list = kzalloc(size, GFP_KERNEL);
> +
> + if (ohci->it_context_list == NULL || ohci->ir_context_list == NULL) {
> + fw_error("Out of memory for it/ir contexts.\n");
> + return cleanup(ohci, CLEANUP_REGISTERS, -ENOMEM);
> + }
> +
> + reg_write(ohci, OHCI1394_PhyUpperBound, 0x00010000);
> + reg_write(ohci, OHCI1394_IntEventClear, ~0);
> + reg_write(ohci, OHCI1394_IntMaskClear, ~0);
> + reg_write(ohci, OHCI1394_IntMaskSet,
> + OHCI1394_selfIDComplete |
> + OHCI1394_RQPkt | OHCI1394_RSPkt |
> + OHCI1394_reqTxComplete | OHCI1394_respTxComplete |
> + OHCI1394_isochRx | OHCI1394_isochTx |
> + OHCI1394_masterIntEnable);
> +
> + bus_options = reg_read(ohci, OHCI1394_BusOptions);
> + max_receive = (bus_options >> 12) & 0xf;
> + link_speed = bus_options & 0x7;
> + guid = (__u64) reg_read(ohci, OHCI1394_GUIDHi) << 32 |
> + reg_read(ohci, OHCI1394_GUIDLo);
> +
> + error_code = fw_core_add_card(&ohci->card, &ohci_driver, &dev->dev,
> + max_receive, link_speed, guid);
> + if (error_code < 0)
> + return cleanup(ohci, CLEANUP_SELF_ID, error_code);
> +
> + fw_notify("Added fw-ohci device %s.\n", dev->dev.bus_id);
> +
> + return 0;
> +}
> +
> +static void pci_remove(struct pci_dev *dev)
> +{
> + struct fw_ohci *ohci;
> +
> + ohci = pci_get_drvdata(dev);
> + if (ohci == NULL)
> + return;

test for event that will never occur

> + free_irq(ohci->dev->irq, ohci);
> + fw_core_remove_card(&ohci->card);
> +
> + /* FIXME: Fail all pending packets here, now that the upper
> + * layers can't queue any more. */
> +
> + software_reset(ohci);
> + cleanup(ohci, CLEANUP_SELF_ID, 0);
> +
> + fw_notify("Removed fw-ohci device.\n");

need to call pci_disable_device(), pci_release_regions()

> +static struct pci_device_id pci_table[] = {
> + {
> + .class = PCI_CLASS_FIREWIRE_OHCI,
> + .class_mask = PCI_ANY_ID,

I'm not sure this is a proper class_mask?

> + .vendor = PCI_ANY_ID,
> + .device = PCI_ANY_ID,
> + .subvendor = PCI_ANY_ID,
> + .subdevice = PCI_ANY_ID,
> + },
> + { }
> +};
> +
> +MODULE_DEVICE_TABLE(pci, pci_table);
> +
> +static struct pci_driver fw_ohci_pci_driver = {
> + .name = ohci_driver_name,
> + .id_table = pci_table,
> + .probe = pci_probe,
> + .remove = pci_remove,
> +};
> +
> +MODULE_AUTHOR("Kristian Høgsberg <krh@bitplanet.net>");
> +MODULE_DESCRIPTION("Driver for PCI OHCI IEEE1394 controllers");
> +MODULE_LICENSE("GPL");
> +
> +static int __init fw_ohci_init(void)
> +{
> + if (pci_register_driver(&fw_ohci_pci_driver)) {
> + fw_error("Failed to register PCI driver.\n");
> + return -EBUSY;
> + }
> +
> + fw_notify("Loaded fw-ohci driver.\n");
> +
> + return 0;

just return pci_register_driver() return value directly, don't invent
your own error when pci_register_driver() already returned a
more-correct error code

> +static void __exit fw_ohci_cleanup(void)
> +{
> + pci_unregister_driver(&fw_ohci_pci_driver);
> + fw_notify("Unloaded fw-ohci driver.\n");
> +}
> +
> +module_init(fw_ohci_init);
> +module_exit(fw_ohci_cleanup);
> diff --git a/drivers/fw/fw-ohci.h b/drivers/fw/fw-ohci.h
> new file mode 100644
> index 0000000..e200b1b
> --- /dev/null
> +++ b/drivers/fw/fw-ohci.h
> @@ -0,0 +1,152 @@
> +#ifndef __fw_ohci_h
> +#define __fw_ohci_h
> +
> +/* OHCI register map */
> +
> +#define OHCI1394_Version 0x000
> +#define OHCI1394_GUID_ROM 0x004
> +#define OHCI1394_ATRetries 0x008
> +#define OHCI1394_CSRData 0x00C
> +#define OHCI1394_CSRCompareData 0x010
> +#define OHCI1394_CSRControl 0x014
> +#define OHCI1394_ConfigROMhdr 0x018
> +#define OHCI1394_BusID 0x01C
> +#define OHCI1394_BusOptions 0x020
> +#define OHCI1394_GUIDHi 0x024
> +#define OHCI1394_GUIDLo 0x028
> +#define OHCI1394_ConfigROMmap 0x034
> +#define OHCI1394_PostedWriteAddressLo 0x038
> +#define OHCI1394_PostedWriteAddressHi 0x03C
> +#define OHCI1394_VendorID 0x040
> +#define OHCI1394_HCControlSet 0x050
> +#define OHCI1394_HCControlClear 0x054
> +#define OHCI1394_HCControl_BIBimageValid 0x80000000
> +#define OHCI1394_HCControl_noByteSwap 0x40000000
> +#define OHCI1394_HCControl_programPhyEnable 0x00800000
> +#define OHCI1394_HCControl_aPhyEnhanceEnable 0x00400000
> +#define OHCI1394_HCControl_LPS 0x00080000
> +#define OHCI1394_HCControl_postedWriteEnable 0x00040000
> +#define OHCI1394_HCControl_linkEnable 0x00020000
> +#define OHCI1394_HCControl_softReset 0x00010000
> +#define OHCI1394_SelfIDBuffer 0x064
> +#define OHCI1394_SelfIDCount 0x068
> +#define OHCI1394_IRMultiChanMaskHiSet 0x070
> +#define OHCI1394_IRMultiChanMaskHiClear 0x074
> +#define OHCI1394_IRMultiChanMaskLoSet 0x078
> +#define OHCI1394_IRMultiChanMaskLoClear 0x07C
> +#define OHCI1394_IntEventSet 0x080
> +#define OHCI1394_IntEventClear 0x084
> +#define OHCI1394_IntMaskSet 0x088
> +#define OHCI1394_IntMaskClear 0x08C
> +#define OHCI1394_IsoXmitIntEventSet 0x090
> +#define OHCI1394_IsoXmitIntEventClear 0x094
> +#define OHCI1394_IsoXmitIntMaskSet 0x098
> +#define OHCI1394_IsoXmitIntMaskClear 0x09C
> +#define OHCI1394_IsoRecvIntEventSet 0x0A0
> +#define OHCI1394_IsoRecvIntEventClear 0x0A4
> +#define OHCI1394_IsoRecvIntMaskSet 0x0A8
> +#define OHCI1394_IsoRecvIntMaskClear 0x0AC
> +#define OHCI1394_InitialBandwidthAvailable 0x0B0
> +#define OHCI1394_InitialChannelsAvailableHi 0x0B4
> +#define OHCI1394_InitialChannelsAvailableLo 0x0B8
> +#define OHCI1394_FairnessControl 0x0DC
> +#define OHCI1394_LinkControlSet 0x0E0
> +#define OHCI1394_LinkControlClear 0x0E4
> +#define OHCI1394_LinkControl_rcvSelfID (1 << 9)
> +#define OHCI1394_LinkControl_rcvPhyPkt (1 << 10)
> +#define OHCI1394_LinkControl_cycleTimerEnable (1 << 20)
> +#define OHCI1394_LinkControl_cycleMaster (1 << 21)
> +#define OHCI1394_LinkControl_cycleSource (1 << 22)
> +#define OHCI1394_NodeID 0x0E8
> +#define OHCI1394_NodeID_idValid 0x80000000
> +#define OHCI1394_PhyControl 0x0EC
> +#define OHCI1394_PhyControl_Read(addr) (((addr) << 8) | 0x00008000)
> +#define OHCI1394_PhyControl_ReadDone 0x80000000
> +#define OHCI1394_PhyControl_ReadData(r) (((r) & 0x00ff0000) >> 16)
> +#define OHCI1394_PhyControl_Write(addr, data) (((addr) << 8) | (data) | 0x00004000)
> +#define OHCI1394_PhyControl_WriteDone 0x00004000
> +#define OHCI1394_IsochronousCycleTimer 0x0F0
> +#define OHCI1394_AsReqFilterHiSet 0x100
> +#define OHCI1394_AsReqFilterHiClear 0x104
> +#define OHCI1394_AsReqFilterLoSet 0x108
> +#define OHCI1394_AsReqFilterLoClear 0x10C
> +#define OHCI1394_PhyReqFilterHiSet 0x110
> +#define OHCI1394_PhyReqFilterHiClear 0x114
> +#define OHCI1394_PhyReqFilterLoSet 0x118
> +#define OHCI1394_PhyReqFilterLoClear 0x11C
> +#define OHCI1394_PhyUpperBound 0x120
> +
> +#define OHCI1394_AsReqTrContextBase 0x180
> +#define OHCI1394_AsReqTrContextControlSet 0x180
> +#define OHCI1394_AsReqTrContextControlClear 0x184
> +#define OHCI1394_AsReqTrCommandPtr 0x18C
> +
> +#define OHCI1394_AsRspTrContextBase 0x1A0
> +#define OHCI1394_AsRspTrContextControlSet 0x1A0
> +#define OHCI1394_AsRspTrContextControlClear 0x1A4
> +#define OHCI1394_AsRspTrCommandPtr 0x1AC
> +
> +#define OHCI1394_AsReqRcvContextBase 0x1C0
> +#define OHCI1394_AsReqRcvContextControlSet 0x1C0
> +#define OHCI1394_AsReqRcvContextControlClear 0x1C4
> +#define OHCI1394_AsReqRcvCommandPtr 0x1CC
> +
> +#define OHCI1394_AsRspRcvContextBase 0x1E0
> +#define OHCI1394_AsRspRcvContextControlSet 0x1E0
> +#define OHCI1394_AsRspRcvContextControlClear 0x1E4
> +#define OHCI1394_AsRspRcvCommandPtr 0x1EC
> +
> +/* Isochronous transmit registers */
> +#define OHCI1394_IsoXmitContextBase(n) (0x200 + 16 * (n))
> +#define OHCI1394_IsoXmitContextControlSet(n) (0x200 + 16 * (n))
> +#define OHCI1394_IsoXmitContextControlClear(n) (0x204 + 16 * (n))
> +#define OHCI1394_IsoXmitCommandPtr(n) (0x20C + 16 * (n))
> +
> +/* Isochronous receive registers */
> +#define OHCI1394_IsoRcvContextControlSet(n) (0x400 + 32 * (n))
> +#define OHCI1394_IsoRcvContextControlClear(n) (0x404 + 32 * (n))
> +#define OHCI1394_IsoRcvCommandPtr(n) (0x40C + 32 * (n))
> +#define OHCI1394_IsoRcvContextMatch(n) (0x410 + 32 * (n))
> +
> +/* Interrupts Mask/Events */
> +#define OHCI1394_reqTxComplete 0x00000001
> +#define OHCI1394_respTxComplete 0x00000002
> +#define OHCI1394_ARRQ 0x00000004
> +#define OHCI1394_ARRS 0x00000008
> +#define OHCI1394_RQPkt 0x00000010
> +#define OHCI1394_RSPkt 0x00000020
> +#define OHCI1394_isochTx 0x00000040
> +#define OHCI1394_isochRx 0x00000080
> +#define OHCI1394_postedWriteErr 0x00000100
> +#define OHCI1394_lockRespErr 0x00000200
> +#define OHCI1394_selfIDComplete 0x00010000
> +#define OHCI1394_busReset 0x00020000
> +#define OHCI1394_phy 0x00080000
> +#define OHCI1394_cycleSynch 0x00100000
> +#define OHCI1394_cycle64Seconds 0x00200000
> +#define OHCI1394_cycleLost 0x00400000
> +#define OHCI1394_cycleInconsistent 0x00800000
> +#define OHCI1394_unrecoverableError 0x01000000
> +#define OHCI1394_cycleTooLong 0x02000000
> +#define OHCI1394_phyRegRcvd 0x04000000
> +#define OHCI1394_masterIntEnable 0x80000000
> +
> +#define OHCI1394_evt_no_status 0x0
> +#define OHCI1394_evt_long_packet 0x2
> +#define OHCI1394_evt_missing_ack 0x3
> +#define OHCI1394_evt_underrun 0x4
> +#define OHCI1394_evt_overrun 0x5
> +#define OHCI1394_evt_descriptor_read 0x6
> +#define OHCI1394_evt_data_read 0x7
> +#define OHCI1394_evt_data_write 0x8
> +#define OHCI1394_evt_bus_reset 0x9
> +#define OHCI1394_evt_timeout 0xa
> +#define OHCI1394_evt_tcode_err 0xb
> +#define OHCI1394_evt_reserved_b 0xc
> +#define OHCI1394_evt_reserved_c 0xd
> +#define OHCI1394_evt_unknown 0xe
> +#define OHCI1394_evt_flushed 0xf
> +
> +#define OHCI1394_phy_tcode 0xe

consider enum{} for reasons mentioned above