diff options
Diffstat (limited to 'drivers/staging/unisys/visorbus/visorchannel.c')
| -rw-r--r-- | drivers/staging/unisys/visorbus/visorchannel.c | 613 |
1 files changed, 613 insertions, 0 deletions
diff --git a/drivers/staging/unisys/visorbus/visorchannel.c b/drivers/staging/unisys/visorbus/visorchannel.c new file mode 100644 index 000000000000..20b63496e9f2 --- /dev/null +++ b/drivers/staging/unisys/visorbus/visorchannel.c @@ -0,0 +1,613 @@ +/* visorchannel_funcs.c + * + * Copyright (C) 2010 - 2013 UNISYS CORPORATION + * All rights reserved. + * + * 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, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for more + * details. + */ + +/* + * This provides Supervisor channel communication primitives, which are + * independent of the mechanism used to access the channel data. + */ + +#include <linux/uuid.h> + +#include "version.h" +#include "visorbus.h" +#include "controlvmchannel.h" + +#define MYDRVNAME "visorchannel" + +#define SPAR_CONSOLEVIDEO_CHANNEL_PROTOCOL_GUID \ + UUID_LE(0x3cd6e705, 0xd6a2, 0x4aa5, \ + 0xad, 0x5c, 0x7b, 0x8, 0x88, 0x9d, 0xff, 0xe2) +static const uuid_le spar_video_guid = SPAR_CONSOLEVIDEO_CHANNEL_PROTOCOL_GUID; + +struct visorchannel { + u64 physaddr; + ulong nbytes; + void __iomem *mapped; + bool requested; + struct channel_header chan_hdr; + uuid_le guid; + ulong size; + bool needs_lock; /* channel creator knows if more than one + * thread will be inserting or removing */ + spinlock_t insert_lock; /* protect head writes in chan_hdr */ + spinlock_t remove_lock; /* protect tail writes in chan_hdr */ + + struct { + struct signal_queue_header req_queue; + struct signal_queue_header rsp_queue; + struct signal_queue_header event_queue; + struct signal_queue_header ack_queue; + } safe_uis_queue; + uuid_le type; + uuid_le inst; +}; + +/* Creates the struct visorchannel abstraction for a data area in memory, + * but does NOT modify this data area. + */ +static struct visorchannel * +visorchannel_create_guts(u64 physaddr, unsigned long channel_bytes, + gfp_t gfp, unsigned long off, + uuid_le guid, bool needs_lock) +{ + struct visorchannel *channel; + int err; + size_t size = sizeof(struct channel_header); + + if (physaddr == 0) + return NULL; + + channel = kzalloc(sizeof(*channel), gfp); + if (!channel) + goto cleanup; + + channel->needs_lock = needs_lock; + spin_lock_init(&channel->insert_lock); + spin_lock_init(&channel->remove_lock); + + /* Video driver constains the efi framebuffer so it will get a + * conflict resource when requesting its full mem region. Since + * we are only using the efi framebuffer for video we can ignore + * this. Remember that we haven't requested it so we don't try to + * release later on. + */ + channel->requested = request_mem_region(physaddr, size, MYDRVNAME); + if (!channel->requested) { + if (uuid_le_cmp(guid, spar_video_guid)) { + /* Not the video channel we care about this */ + goto cleanup; + } + } + + channel->mapped = ioremap_cache(physaddr, size); + if (!channel->mapped) { + release_mem_region(physaddr, size); + goto cleanup; + } + + channel->physaddr = physaddr; + channel->nbytes = size; + + err = visorchannel_read(channel, 0, &channel->chan_hdr, + sizeof(struct channel_header)); + if (err) + goto cleanup; + + /* we had better be a CLIENT of this channel */ + if (channel_bytes == 0) + channel_bytes = (ulong)channel->chan_hdr.size; + if (uuid_le_cmp(guid, NULL_UUID_LE) == 0) + guid = channel->chan_hdr.chtype; + + iounmap(channel->mapped); + if (channel->requested) + release_mem_region(channel->physaddr, channel->nbytes); + channel->mapped = NULL; + channel->requested = request_mem_region(channel->physaddr, + channel_bytes, MYDRVNAME); + if (!channel->requested) { + if (uuid_le_cmp(guid, spar_video_guid)) { + /* Different we care about this */ + goto cleanup; + } + } + + channel->mapped = ioremap_cache(channel->physaddr, channel_bytes); + if (!channel->mapped) { + release_mem_region(channel->physaddr, channel_bytes); + goto cleanup; + } + + channel->nbytes = channel_bytes; + + channel->size = channel_bytes; + channel->guid = guid; + return channel; + +cleanup: + visorchannel_destroy(channel); + return NULL; +} + +struct visorchannel * +visorchannel_create(u64 physaddr, unsigned long channel_bytes, + gfp_t gfp, uuid_le guid) +{ + return visorchannel_create_guts(physaddr, channel_bytes, gfp, 0, guid, + false); +} +EXPORT_SYMBOL_GPL(visorchannel_create); + +struct visorchannel * +visorchannel_create_with_lock(u64 physaddr, unsigned long channel_bytes, + gfp_t gfp, uuid_le guid) +{ + return visorchannel_create_guts(physaddr, channel_bytes, gfp, 0, guid, + true); +} +EXPORT_SYMBOL_GPL(visorchannel_create_with_lock); + +void +visorchannel_destroy(struct visorchannel *channel) +{ + if (!channel) + return; + if (channel->mapped) { + iounmap(channel->mapped); + if (channel->requested) + release_mem_region(channel->physaddr, channel->nbytes); + } + kfree(channel); +} +EXPORT_SYMBOL_GPL(visorchannel_destroy); + +u64 +visorchannel_get_physaddr(struct visorchannel *channel) +{ + return channel->physaddr; +} +EXPORT_SYMBOL_GPL(visorchannel_get_physaddr); + +ulong +visorchannel_get_nbytes(struct visorchannel *channel) +{ + return channel->size; +} +EXPORT_SYMBOL_GPL(visorchannel_get_nbytes); + +char * +visorchannel_uuid_id(uuid_le *guid, char *s) +{ + sprintf(s, "%pUL", guid); + return s; +} +EXPORT_SYMBOL_GPL(visorchannel_uuid_id); + +char * +visorchannel_id(struct visorchannel *channel, char *s) +{ + return visorchannel_uuid_id(&channel->guid, s); +} +EXPORT_SYMBOL_GPL(visorchannel_id); + +char * +visorchannel_zoneid(struct visorchannel *channel, char *s) +{ + return visorchannel_uuid_id(&channel->chan_hdr.zone_uuid, s); +} +EXPORT_SYMBOL_GPL(visorchannel_zoneid); + +u64 +visorchannel_get_clientpartition(struct visorchannel *channel) +{ + return channel->chan_hdr.partition_handle; +} +EXPORT_SYMBOL_GPL(visorchannel_get_clientpartition); + +int +visorchannel_set_clientpartition(struct visorchannel *channel, + u64 partition_handle) +{ + channel->chan_hdr.partition_handle = partition_handle; + return 0; +} +EXPORT_SYMBOL_GPL(visorchannel_set_clientpartition); + +uuid_le +visorchannel_get_uuid(struct visorchannel *channel) +{ + return channel->guid; +} +EXPORT_SYMBOL_GPL(visorchannel_get_uuid); + +int +visorchannel_read(struct visorchannel *channel, ulong offset, + void *local, ulong nbytes) +{ + if (offset + nbytes > channel->nbytes) + return -EIO; + + memcpy_fromio(local, channel->mapped + offset, nbytes); + + return 0; +} +EXPORT_SYMBOL_GPL(visorchannel_read); + +int +visorchannel_write(struct visorchannel *channel, ulong offset, + void *local, ulong nbytes) +{ + size_t chdr_size = sizeof(struct channel_header); + size_t copy_size; + + if (offset + nbytes > channel->nbytes) + return -EIO; + + if (offset < chdr_size) { + copy_size = min(chdr_size - offset, nbytes); + memcpy(&channel->chan_hdr + offset, local, copy_size); + } + + memcpy_toio(channel->mapped + offset, local, nbytes); + + return 0; +} +EXPORT_SYMBOL_GPL(visorchannel_write); + +int +visorchannel_clear(struct visorchannel *channel, ulong offset, u8 ch, + ulong nbytes) +{ + int err; + int bufsize = PAGE_SIZE; + int written = 0; + u8 *buf; + + buf = (u8 *) __get_free_page(GFP_KERNEL); + if (!buf) + return -ENOMEM; + + memset(buf, ch, bufsize); + + while (nbytes > 0) { + int thisbytes = bufsize; + + if (nbytes < thisbytes) + thisbytes = nbytes; + err = visorchannel_write(channel, offset + written, + buf, thisbytes); + if (err) + goto cleanup; + + written += thisbytes; + nbytes -= thisbytes; + } + err = 0; + +cleanup: + free_page((unsigned long) buf); + return err; +} +EXPORT_SYMBOL_GPL(visorchannel_clear); + +void __iomem * +visorchannel_get_header(struct visorchannel *channel) +{ + return (void __iomem *)&channel->chan_hdr; +} +EXPORT_SYMBOL_GPL(visorchannel_get_header); + +/** Return offset of a specific SIGNAL_QUEUE_HEADER from the beginning of a + * channel header + */ +#define SIG_QUEUE_OFFSET(chan_hdr, q) \ + ((chan_hdr)->ch_space_offset + \ + ((q) * sizeof(struct signal_queue_header))) + +/** Return offset of a specific queue entry (data) from the beginning of a + * channel header + */ +#define SIG_DATA_OFFSET(chan_hdr, q, sig_hdr, slot) \ + (SIG_QUEUE_OFFSET(chan_hdr, q) + (sig_hdr)->sig_base_offset + \ + ((slot) * (sig_hdr)->signal_size)) + +/** Write the contents of a specific field within a SIGNAL_QUEUE_HEADER back + * into host memory + */ +#define SIG_WRITE_FIELD(channel, queue, sig_hdr, FIELD) \ + (visorchannel_write(channel, \ + SIG_QUEUE_OFFSET(&channel->chan_hdr, queue)+ \ + offsetof(struct signal_queue_header, FIELD), \ + &((sig_hdr)->FIELD), \ + sizeof((sig_hdr)->FIELD)) >= 0) + +static bool +sig_read_header(struct visorchannel *channel, u32 queue, + struct signal_queue_header *sig_hdr) +{ + int err; + + if (channel->chan_hdr.ch_space_offset < sizeof(struct channel_header)) + return false; + + /* Read the appropriate SIGNAL_QUEUE_HEADER into local memory. */ + err = visorchannel_read(channel, + SIG_QUEUE_OFFSET(&channel->chan_hdr, queue), + sig_hdr, sizeof(struct signal_queue_header)); + if (err) + return false; + + return true; +} + +static inline bool +sig_read_data(struct visorchannel *channel, u32 queue, + struct signal_queue_header *sig_hdr, u32 slot, void *data) +{ + int err; + int signal_data_offset = SIG_DATA_OFFSET(&channel->chan_hdr, queue, + sig_hdr, slot); + + err = visorchannel_read(channel, signal_data_offset, + data, sig_hdr->signal_size); + if (err) + return false; + + return true; +} + +static inline bool +sig_write_data(struct visorchannel *channel, u32 queue, + struct signal_queue_header *sig_hdr, u32 slot, void *data) +{ + int err; + int signal_data_offset = SIG_DATA_OFFSET(&channel->chan_hdr, queue, + sig_hdr, slot); + + err = visorchannel_write(channel, signal_data_offset, + data, sig_hdr->signal_size); + if (err) + return false; + + return true; +} + +static bool +signalremove_inner(struct visorchannel *channel, u32 queue, void *msg) +{ + struct signal_queue_header sig_hdr; + + if (!sig_read_header(channel, queue, &sig_hdr)) + return false; + if (sig_hdr.head == sig_hdr.tail) + return false; /* no signals to remove */ + + sig_hdr.tail = (sig_hdr.tail + 1) % sig_hdr.max_slots; + if (!sig_read_data(channel, queue, &sig_hdr, sig_hdr.tail, msg)) + return false; + sig_hdr.num_received++; + + /* For each data field in SIGNAL_QUEUE_HEADER that was modified, + * update host memory. + */ + mb(); /* required for channel synch */ + if (!SIG_WRITE_FIELD(channel, queue, &sig_hdr, tail)) + return false; + if (!SIG_WRITE_FIELD(channel, queue, &sig_hdr, num_received)) + return false; + return true; +} + +bool +visorchannel_signalremove(struct visorchannel *channel, u32 queue, void *msg) +{ + bool rc; + + if (channel->needs_lock) { + spin_lock(&channel->remove_lock); + rc = signalremove_inner(channel, queue, msg); + spin_unlock(&channel->remove_lock); + } else { + rc = signalremove_inner(channel, queue, msg); + } + + return rc; +} +EXPORT_SYMBOL_GPL(visorchannel_signalremove); + +static bool +signalinsert_inner(struct visorchannel *channel, u32 queue, void *msg) +{ + struct signal_queue_header sig_hdr; + + if (!sig_read_header(channel, queue, &sig_hdr)) + return false; + + sig_hdr.head = ((sig_hdr.head + 1) % sig_hdr.max_slots); + if (sig_hdr.head == sig_hdr.tail) { + sig_hdr.num_overflows++; + visorchannel_write(channel, + SIG_QUEUE_OFFSET(&channel->chan_hdr, queue) + + offsetof(struct signal_queue_header, + num_overflows), + &(sig_hdr.num_overflows), + sizeof(sig_hdr.num_overflows)); + return false; + } + + if (!sig_write_data(channel, queue, &sig_hdr, sig_hdr.head, msg)) + return false; + + sig_hdr.num_sent++; + + /* For each data field in SIGNAL_QUEUE_HEADER that was modified, + * update host memory. + */ + mb(); /* required for channel synch */ + if (!SIG_WRITE_FIELD(channel, queue, &sig_hdr, head)) + return false; + if (!SIG_WRITE_FIELD(channel, queue, &sig_hdr, num_sent)) + return false; + + return true; +} + +bool +visorchannel_signalinsert(struct visorchannel *channel, u32 queue, void *msg) +{ + bool rc; + + if (channel->needs_lock) { + spin_lock(&channel->insert_lock); + rc = signalinsert_inner(channel, queue, msg); + spin_unlock(&channel->insert_lock); + } else { + rc = signalinsert_inner(channel, queue, msg); + } + + return rc; +} +EXPORT_SYMBOL_GPL(visorchannel_signalinsert); + +int +visorchannel_signalqueue_slots_avail(struct visorchannel *channel, u32 queue) +{ + struct signal_queue_header sig_hdr; + u32 slots_avail, slots_used; + u32 head, tail; + + if (!sig_read_header(channel, queue, &sig_hdr)) + return 0; + head = sig_hdr.head; + tail = sig_hdr.tail; + if (head < tail) + head = head + sig_hdr.max_slots; + slots_used = (head - tail); + slots_avail = sig_hdr.max_signals - slots_used; + return (int)slots_avail; +} +EXPORT_SYMBOL_GPL(visorchannel_signalqueue_slots_avail); + +int +visorchannel_signalqueue_max_slots(struct visorchannel *channel, u32 queue) +{ + struct signal_queue_header sig_hdr; + + if (!sig_read_header(channel, queue, &sig_hdr)) + return 0; + return (int)sig_hdr.max_signals; +} +EXPORT_SYMBOL_GPL(visorchannel_signalqueue_max_slots); + +static void +sigqueue_debug(struct signal_queue_header *q, int which, struct seq_file *seq) +{ + seq_printf(seq, "Signal Queue #%d\n", which); + seq_printf(seq, " VersionId = %lu\n", (ulong)q->version); + seq_printf(seq, " Type = %lu\n", (ulong)q->chtype); + seq_printf(seq, " oSignalBase = %llu\n", + (long long)q->sig_base_offset); + seq_printf(seq, " SignalSize = %lu\n", (ulong)q->signal_size); + seq_printf(seq, " MaxSignalSlots = %lu\n", + (ulong)q->max_slots); + seq_printf(seq, " MaxSignals = %lu\n", (ulong)q->max_signals); + seq_printf(seq, " FeatureFlags = %-16.16Lx\n", + (long long)q->features); + seq_printf(seq, " NumSignalsSent = %llu\n", + (long long)q->num_sent); + seq_printf(seq, " NumSignalsReceived = %llu\n", + (long long)q->num_received); + seq_printf(seq, " NumOverflows = %llu\n", + (long long)q->num_overflows); + seq_printf(seq, " Head = %lu\n", (ulong)q->head); + seq_printf(seq, " Tail = %lu\n", (ulong)q->tail); +} + +void +visorchannel_debug(struct visorchannel *channel, int num_queues, + struct seq_file *seq, u32 off) +{ + u64 addr = 0; + ulong nbytes = 0, nbytes_region = 0; + struct channel_header hdr; + struct channel_header *phdr = &hdr; + int i = 0; + int errcode = 0; + + if (!channel) + return; + + addr = visorchannel_get_physaddr(channel); + nbytes_region = visorchannel_get_nbytes(channel); + errcode = visorchannel_read(channel, off, + phdr, sizeof(struct channel_header)); + if (errcode < 0) { + seq_printf(seq, + "Read of channel header failed with errcode=%d)\n", + errcode); + if (off == 0) { + phdr = &channel->chan_hdr; + seq_puts(seq, "(following data may be stale)\n"); + } else { + return; + } + } + nbytes = (ulong)(phdr->size); + seq_printf(seq, "--- Begin channel @0x%-16.16Lx for 0x%lx bytes (region=0x%lx bytes) ---\n", + addr + off, nbytes, nbytes_region); + seq_printf(seq, "Type = %pUL\n", &phdr->chtype); + seq_printf(seq, "ZoneGuid = %pUL\n", &phdr->zone_uuid); + seq_printf(seq, "Signature = 0x%-16.16Lx\n", + (long long)phdr->signature); + seq_printf(seq, "LegacyState = %lu\n", (ulong)phdr->legacy_state); + seq_printf(seq, "SrvState = %lu\n", (ulong)phdr->srv_state); + seq_printf(seq, "CliStateBoot = %lu\n", (ulong)phdr->cli_state_boot); + seq_printf(seq, "CliStateOS = %lu\n", (ulong)phdr->cli_state_os); + seq_printf(seq, "HeaderSize = %lu\n", (ulong)phdr->header_size); + seq_printf(seq, "Size = %llu\n", (long long)phdr->size); + seq_printf(seq, "Features = 0x%-16.16llx\n", + (long long)phdr->features); + seq_printf(seq, "PartitionHandle = 0x%-16.16llx\n", + (long long)phdr->partition_handle); + seq_printf(seq, "Handle = 0x%-16.16llx\n", + (long long)phdr->handle); + seq_printf(seq, "VersionId = %lu\n", (ulong)phdr->version_id); + seq_printf(seq, "oChannelSpace = %llu\n", + (long long)phdr->ch_space_offset); + if ((phdr->ch_space_offset == 0) || (errcode < 0)) + ; + else + for (i = 0; i < num_queues; i++) { + struct signal_queue_header q; + + errcode = visorchannel_read(channel, + off + + phdr->ch_space_offset + + (i * sizeof(q)), + &q, sizeof(q)); + if (errcode < 0) { + seq_printf(seq, + "failed to read signal queue #%d from channel @0x%-16.16Lx errcode=%d\n", + i, addr, errcode); + continue; + } + sigqueue_debug(&q, i, seq); + } + seq_printf(seq, "--- End channel @0x%-16.16Lx for 0x%lx bytes ---\n", + addr + off, nbytes); +} +EXPORT_SYMBOL_GPL(visorchannel_debug); |