diff options
Diffstat (limited to 'drivers/net/ipa/gsi_trans.c')
| -rw-r--r-- | drivers/net/ipa/gsi_trans.c | 433 |
1 files changed, 205 insertions, 228 deletions
diff --git a/drivers/net/ipa/gsi_trans.c b/drivers/net/ipa/gsi_trans.c index 1544564bc283..26b7f683a3e1 100644 --- a/drivers/net/ipa/gsi_trans.c +++ b/drivers/net/ipa/gsi_trans.c @@ -1,7 +1,7 @@ // SPDX-License-Identifier: GPL-2.0 /* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved. - * Copyright (C) 2019-2020 Linaro Ltd. + * Copyright (C) 2019-2022 Linaro Ltd. */ #include <linux/types.h> @@ -22,37 +22,36 @@ * DOC: GSI Transactions * * A GSI transaction abstracts the behavior of a GSI channel by representing - * everything about a related group of IPA commands in a single structure. - * (A "command" in this sense is either a data transfer or an IPA immediate + * everything about a related group of IPA operations in a single structure. + * (A "operation" in this sense is either a data transfer or an IPA immediate * command.) Most details of interaction with the GSI hardware are managed - * by the GSI transaction core, allowing users to simply describe commands + * by the GSI transaction core, allowing users to simply describe operations * to be performed. When a transaction has completed a callback function * (dependent on the type of endpoint associated with the channel) allows * cleanup of resources associated with the transaction. * - * To perform a command (or set of them), a user of the GSI transaction + * To perform an operation (or set of them), a user of the GSI transaction * interface allocates a transaction, indicating the number of TREs required - * (one per command). If sufficient TREs are available, they are reserved + * (one per operation). If sufficient TREs are available, they are reserved * for use in the transaction and the allocation succeeds. This way - * exhaustion of the available TREs in a channel ring is detected - * as early as possible. All resources required to complete a transaction - * are allocated at transaction allocation time. + * exhaustion of the available TREs in a channel ring is detected as early + * as possible. Any other resources that might be needed to complete a + * transaction are also allocated when the transaction is allocated. * - * Commands performed as part of a transaction are represented in an array - * of Linux scatterlist structures. This array is allocated with the - * transaction, and its entries are initialized using standard scatterlist - * functions (such as sg_set_buf() or skb_to_sgvec()). + * Operations performed as part of a transaction are represented in an array + * of Linux scatterlist structures, allocated with the transaction. These + * scatterlist structures are initialized by "adding" operations to the + * transaction. If a buffer in an operation must be mapped for DMA, this is + * done at the time it is added to the transaction. It is possible for a + * mapping error to occur when an operation is added. In this case the + * transaction should simply be freed; this correctly releases resources + * associated with the transaction. * - * Once a transaction's scatterlist structures have been initialized, the - * transaction is committed. The caller is responsible for mapping buffers - * for DMA if necessary, and this should be done *before* allocating - * the transaction. Between a successful allocation and commit of a - * transaction no errors should occur. - * - * Committing transfers ownership of the entire transaction to the GSI - * transaction core. The GSI transaction code formats the content of - * the scatterlist array into the channel ring buffer and informs the - * hardware that new TREs are available to process. + * Once all operations have been successfully added to a transaction, the + * transaction is committed. Committing transfers ownership of the entire + * transaction to the GSI transaction core. The GSI transaction code + * formats the content of the scatterlist array into the channel ring + * buffer and informs the hardware that new TREs are available to process. * * The last TRE in each transaction is marked to interrupt the AP when the * GSI hardware has completed it. Because transfers described by TREs are @@ -125,11 +124,10 @@ void gsi_trans_pool_exit(struct gsi_trans_pool *pool) memset(pool, 0, sizeof(*pool)); } -/* Allocate the requested number of (zeroed) entries from the pool */ -/* Home-grown DMA pool. This way we can preallocate and use the tre_count - * to guarantee allocations will succeed. Even though we specify max_alloc - * (and it can be more than one), we only allow allocation of a single - * element from a DMA pool. +/* Home-grown DMA pool. This way we can preallocate the pool, and guarantee + * allocations will succeed. The immediate commands in a transaction can + * require up to max_alloc elements from the pool. But we only allow + * allocation of a single element from a DMA pool at a time. */ int gsi_trans_pool_init_dma(struct device *dev, struct gsi_trans_pool *pool, size_t size, u32 count, u32 max_alloc) @@ -214,26 +212,14 @@ void *gsi_trans_pool_alloc_dma(struct gsi_trans_pool *pool, dma_addr_t *addr) return pool->base + offset; } -/* Return the pool element that immediately follows the one given. - * This only works done if elements are allocated one at a time. - */ -void *gsi_trans_pool_next(struct gsi_trans_pool *pool, void *element) +/* Map a TRE ring entry index to the transaction it is associated with */ +static void gsi_trans_map(struct gsi_trans *trans, u32 index) { - void *end = pool->base + pool->count * pool->size; - - WARN_ON(element < pool->base); - WARN_ON(element >= end); - WARN_ON(pool->max_alloc != 1); - - element += pool->size; + struct gsi_channel *channel = &trans->gsi->channel[trans->channel_id]; - return element < end ? element : pool->base; -} + /* The completion event will indicate the last TRE used */ + index += trans->used_count - 1; -/* Map a given ring entry index to the transaction associated with it */ -static void gsi_channel_trans_map(struct gsi_channel *channel, u32 index, - struct gsi_trans *trans) -{ /* Note: index *must* be used modulo the ring count here */ channel->trans_info.map[index % channel->tre_ring.count] = trans; } @@ -249,52 +235,63 @@ gsi_channel_trans_mapped(struct gsi_channel *channel, u32 index) /* Return the oldest completed transaction for a channel (or null) */ struct gsi_trans *gsi_channel_trans_complete(struct gsi_channel *channel) { - return list_first_entry_or_null(&channel->trans_info.complete, - struct gsi_trans, links); + struct gsi_trans_info *trans_info = &channel->trans_info; + u16 trans_id = trans_info->completed_id; + + if (trans_id == trans_info->pending_id) { + gsi_channel_update(channel); + if (trans_id == trans_info->pending_id) + return NULL; + } + + return &trans_info->trans[trans_id %= channel->tre_count]; } -/* Move a transaction from the allocated list to the pending list */ -static void gsi_trans_move_pending(struct gsi_trans *trans) +/* Move a transaction from allocated to committed state */ +static void gsi_trans_move_committed(struct gsi_trans *trans) { struct gsi_channel *channel = &trans->gsi->channel[trans->channel_id]; struct gsi_trans_info *trans_info = &channel->trans_info; - spin_lock_bh(&trans_info->spinlock); + /* This allocated transaction is now committed */ + trans_info->allocated_id++; +} - list_move_tail(&trans->links, &trans_info->pending); +/* Move committed transactions to pending state */ +static void gsi_trans_move_pending(struct gsi_trans *trans) +{ + struct gsi_channel *channel = &trans->gsi->channel[trans->channel_id]; + struct gsi_trans_info *trans_info = &channel->trans_info; + u16 trans_index = trans - &trans_info->trans[0]; + u16 delta; - spin_unlock_bh(&trans_info->spinlock); + /* These committed transactions are now pending */ + delta = trans_index - trans_info->committed_id + 1; + trans_info->committed_id += delta % channel->tre_count; } -/* Move a transaction and all of its predecessors from the pending list - * to the completed list. - */ +/* Move pending transactions to completed state */ void gsi_trans_move_complete(struct gsi_trans *trans) { struct gsi_channel *channel = &trans->gsi->channel[trans->channel_id]; struct gsi_trans_info *trans_info = &channel->trans_info; - struct list_head list; - - spin_lock_bh(&trans_info->spinlock); - - /* Move this transaction and all predecessors to completed list */ - list_cut_position(&list, &trans_info->pending, &trans->links); - list_splice_tail(&list, &trans_info->complete); + u16 trans_index = trans - trans_info->trans; + u16 delta; - spin_unlock_bh(&trans_info->spinlock); + /* These pending transactions are now completed */ + delta = trans_index - trans_info->pending_id + 1; + delta %= channel->tre_count; + trans_info->pending_id += delta; } -/* Move a transaction from the completed list to the polled list */ +/* Move a transaction from completed to polled state */ void gsi_trans_move_polled(struct gsi_trans *trans) { struct gsi_channel *channel = &trans->gsi->channel[trans->channel_id]; struct gsi_trans_info *trans_info = &channel->trans_info; - spin_lock_bh(&trans_info->spinlock); - - list_move_tail(&trans->links, &trans_info->polled); - - spin_unlock_bh(&trans_info->spinlock); + /* This completed transaction is now polled */ + trans_info->completed_id++; } /* Reserve some number of TREs on a channel. Returns true if successful */ @@ -320,6 +317,17 @@ gsi_trans_tre_release(struct gsi_trans_info *trans_info, u32 tre_count) atomic_add(tre_count, &trans_info->tre_avail); } +/* Return true if no transactions are allocated, false otherwise */ +bool gsi_channel_trans_idle(struct gsi *gsi, u32 channel_id) +{ + u32 tre_max = gsi_channel_tre_max(gsi, channel_id); + struct gsi_trans_info *trans_info; + + trans_info = &gsi->channel[channel_id].trans_info; + + return atomic_read(&trans_info->tre_avail) == tre_max; +} + /* Allocate a GSI transaction on a channel */ struct gsi_trans *gsi_channel_trans_alloc(struct gsi *gsi, u32 channel_id, u32 tre_count, @@ -328,85 +336,78 @@ struct gsi_trans *gsi_channel_trans_alloc(struct gsi *gsi, u32 channel_id, struct gsi_channel *channel = &gsi->channel[channel_id]; struct gsi_trans_info *trans_info; struct gsi_trans *trans; + u16 trans_index; - if (WARN_ON(tre_count > gsi_channel_trans_tre_max(gsi, channel_id))) + if (WARN_ON(tre_count > channel->trans_tre_max)) return NULL; trans_info = &channel->trans_info; - /* We reserve the TREs now, but consume them at commit time. - * If there aren't enough available, we're done. - */ + /* If we can't reserve the TREs for the transaction, we're done */ if (!gsi_trans_tre_reserve(trans_info, tre_count)) return NULL; - /* Allocate and initialize non-zero fields in the the transaction */ - trans = gsi_trans_pool_alloc(&trans_info->pool, 1); + trans_index = trans_info->free_id % channel->tre_count; + trans = &trans_info->trans[trans_index]; + memset(trans, 0, sizeof(*trans)); + + /* Initialize non-zero fields in the transaction */ trans->gsi = gsi; trans->channel_id = channel_id; - trans->tre_count = tre_count; + trans->rsvd_count = tre_count; init_completion(&trans->completion); - /* Allocate the scatterlist and (if requested) info entries. */ + /* Allocate the scatterlist */ trans->sgl = gsi_trans_pool_alloc(&trans_info->sg_pool, tre_count); sg_init_marker(trans->sgl, tre_count); trans->direction = direction; - - spin_lock_bh(&trans_info->spinlock); - - list_add_tail(&trans->links, &trans_info->alloc); - - spin_unlock_bh(&trans_info->spinlock); - refcount_set(&trans->refcount, 1); + /* This free transaction is now allocated */ + trans_info->free_id++; + return trans; } /* Free a previously-allocated transaction */ void gsi_trans_free(struct gsi_trans *trans) { - refcount_t *refcount = &trans->refcount; struct gsi_trans_info *trans_info; - bool last; - /* We must hold the lock to release the last reference */ - if (refcount_dec_not_one(refcount)) + if (!refcount_dec_and_test(&trans->refcount)) return; + /* Unused transactions are allocated but never committed, pending, + * completed, or polled. + */ trans_info = &trans->gsi->channel[trans->channel_id].trans_info; + if (!trans->used_count) { + trans_info->allocated_id++; + trans_info->committed_id++; + trans_info->pending_id++; + trans_info->completed_id++; + } else { + ipa_gsi_trans_release(trans); + } - spin_lock_bh(&trans_info->spinlock); - - /* Reference might have been added before we got the lock */ - last = refcount_dec_and_test(refcount); - if (last) - list_del(&trans->links); - - spin_unlock_bh(&trans_info->spinlock); - - if (!last) - return; - - ipa_gsi_trans_release(trans); + /* This transaction is now free */ + trans_info->polled_id++; /* Releasing the reserved TREs implicitly frees the sgl[] and * (if present) info[] arrays, plus the transaction itself. */ - gsi_trans_tre_release(trans_info, trans->tre_count); + gsi_trans_tre_release(trans_info, trans->rsvd_count); } /* Add an immediate command to a transaction */ void gsi_trans_cmd_add(struct gsi_trans *trans, void *buf, u32 size, - dma_addr_t addr, enum dma_data_direction direction, - enum ipa_cmd_opcode opcode) + dma_addr_t addr, enum ipa_cmd_opcode opcode) { - struct ipa_cmd_info *info; - u32 which = trans->used++; + u32 which = trans->used_count++; struct scatterlist *sg; - WARN_ON(which >= trans->tre_count); + WARN_ON(which >= trans->rsvd_count); /* Commands are quite different from data transfer requests. * Their payloads come from a pool whose memory is allocated @@ -427,9 +428,7 @@ void gsi_trans_cmd_add(struct gsi_trans *trans, void *buf, u32 size, sg_dma_address(sg) = addr; sg_dma_len(sg) = size; - info = &trans->info[which]; - info->opcode = opcode; - info->direction = direction; + trans->cmd_opcode[which] = opcode; } /* Add a page transfer to a transaction. It will fill the only TRE. */ @@ -439,9 +438,9 @@ int gsi_trans_page_add(struct gsi_trans *trans, struct page *page, u32 size, struct scatterlist *sg = &trans->sgl[0]; int ret; - if (WARN_ON(trans->tre_count != 1)) + if (WARN_ON(trans->rsvd_count != 1)) return -EINVAL; - if (WARN_ON(trans->used)) + if (WARN_ON(trans->used_count)) return -EINVAL; sg_set_page(sg, page, size, offset); @@ -449,7 +448,7 @@ int gsi_trans_page_add(struct gsi_trans *trans, struct page *page, u32 size, if (!ret) return -ENOMEM; - trans->used++; /* Transaction now owns the (DMA mapped) page */ + trans->used_count++; /* Transaction now owns the (DMA mapped) page */ return 0; } @@ -458,25 +457,26 @@ int gsi_trans_page_add(struct gsi_trans *trans, struct page *page, u32 size, int gsi_trans_skb_add(struct gsi_trans *trans, struct sk_buff *skb) { struct scatterlist *sg = &trans->sgl[0]; - u32 used; + u32 used_count; int ret; - if (WARN_ON(trans->tre_count != 1)) + if (WARN_ON(trans->rsvd_count != 1)) return -EINVAL; - if (WARN_ON(trans->used)) + if (WARN_ON(trans->used_count)) return -EINVAL; /* skb->len will not be 0 (checked early) */ ret = skb_to_sgvec(skb, sg, 0, skb->len); if (ret < 0) return ret; - used = ret; + used_count = ret; - ret = dma_map_sg(trans->gsi->dev, sg, used, trans->direction); + ret = dma_map_sg(trans->gsi->dev, sg, used_count, trans->direction); if (!ret) return -ENOMEM; - trans->used += used; /* Transaction now owns the (DMA mapped) skb */ + /* Transaction now owns the (DMA mapped) skb */ + trans->used_count += used_count; return 0; } @@ -535,68 +535,64 @@ static void gsi_trans_tre_fill(struct gsi_tre *dest_tre, dma_addr_t addr, * * Formats channel ring TRE entries based on the content of the scatterlist. * Maps a transaction pointer to the last ring entry used for the transaction, - * so it can be recovered when it completes. Moves the transaction to the - * pending list. Finally, updates the channel ring pointer and optionally + * so it can be recovered when it completes. Moves the transaction to + * pending state. Finally, updates the channel ring pointer and optionally * rings the doorbell. */ static void __gsi_trans_commit(struct gsi_trans *trans, bool ring_db) { struct gsi_channel *channel = &trans->gsi->channel[trans->channel_id]; - struct gsi_ring *ring = &channel->tre_ring; + struct gsi_ring *tre_ring = &channel->tre_ring; enum ipa_cmd_opcode opcode = IPA_CMD_NONE; bool bei = channel->toward_ipa; - struct ipa_cmd_info *info; struct gsi_tre *dest_tre; struct scatterlist *sg; u32 byte_count = 0; + u8 *cmd_opcode; u32 avail; u32 i; - WARN_ON(!trans->used); + WARN_ON(!trans->used_count); /* Consume the entries. If we cross the end of the ring while * filling them we'll switch to the beginning to finish. * If there is no info array we're doing a simple data * transfer request, whose opcode is IPA_CMD_NONE. */ - info = trans->info ? &trans->info[0] : NULL; - avail = ring->count - ring->index % ring->count; - dest_tre = gsi_ring_virt(ring, ring->index); - for_each_sg(trans->sgl, sg, trans->used, i) { - bool last_tre = i == trans->used - 1; + cmd_opcode = channel->command ? &trans->cmd_opcode[0] : NULL; + avail = tre_ring->count - tre_ring->index % tre_ring->count; + dest_tre = gsi_ring_virt(tre_ring, tre_ring->index); + for_each_sg(trans->sgl, sg, trans->used_count, i) { + bool last_tre = i == trans->used_count - 1; dma_addr_t addr = sg_dma_address(sg); u32 len = sg_dma_len(sg); byte_count += len; if (!avail--) - dest_tre = gsi_ring_virt(ring, 0); - if (info) - opcode = info++->opcode; + dest_tre = gsi_ring_virt(tre_ring, 0); + if (cmd_opcode) + opcode = *cmd_opcode++; gsi_trans_tre_fill(dest_tre, addr, len, last_tre, bei, opcode); dest_tre++; } - ring->index += trans->used; - - if (channel->toward_ipa) { - /* We record TX bytes when they are sent */ - trans->len = byte_count; - trans->trans_count = channel->trans_count; - trans->byte_count = channel->byte_count; - channel->trans_count++; - channel->byte_count += byte_count; - } + /* Associate the TRE with the transaction */ + gsi_trans_map(trans, tre_ring->index); + + tre_ring->index += trans->used_count; - /* Associate the last TRE with the transaction */ - gsi_channel_trans_map(channel, ring->index - 1, trans); + trans->len = byte_count; + if (channel->toward_ipa) + gsi_trans_tx_committed(trans); - gsi_trans_move_pending(trans); + gsi_trans_move_committed(trans); /* Ring doorbell if requested, or if all TREs are allocated */ if (ring_db || !atomic_read(&channel->trans_info.tre_avail)) { /* Report what we're handing off to hardware for TX channels */ if (channel->toward_ipa) - gsi_channel_tx_queued(channel); + gsi_trans_tx_queued(trans); + gsi_trans_move_pending(trans); gsi_channel_doorbell(channel); } } @@ -604,7 +600,7 @@ static void __gsi_trans_commit(struct gsi_trans *trans, bool ring_db) /* Commit a GSI transaction */ void gsi_trans_commit(struct gsi_trans *trans, bool ring_db) { - if (trans->used) + if (trans->used_count) __gsi_trans_commit(trans, ring_db); else gsi_trans_free(trans); @@ -613,7 +609,7 @@ void gsi_trans_commit(struct gsi_trans *trans, bool ring_db) /* Commit a GSI transaction and wait for it to complete */ void gsi_trans_commit_wait(struct gsi_trans *trans) { - if (!trans->used) + if (!trans->used_count) goto out_trans_free; refcount_inc(&trans->refcount); @@ -626,34 +622,12 @@ out_trans_free: gsi_trans_free(trans); } -/* Commit a GSI transaction and wait for it to complete, with timeout */ -int gsi_trans_commit_wait_timeout(struct gsi_trans *trans, - unsigned long timeout) -{ - unsigned long timeout_jiffies = msecs_to_jiffies(timeout); - unsigned long remaining = 1; /* In case of empty transaction */ - - if (!trans->used) - goto out_trans_free; - - refcount_inc(&trans->refcount); - - __gsi_trans_commit(trans, true); - - remaining = wait_for_completion_timeout(&trans->completion, - timeout_jiffies); -out_trans_free: - gsi_trans_free(trans); - - return remaining ? 0 : -ETIMEDOUT; -} - /* Process the completion of a transaction; called while polling */ void gsi_trans_complete(struct gsi_trans *trans) { /* If the entire SGL was mapped when added, unmap it now */ if (trans->direction != DMA_NONE) - dma_unmap_sg(trans->gsi->dev, trans->sgl, trans->used, + dma_unmap_sg(trans->gsi->dev, trans->sgl, trans->used_count, trans->direction); ipa_gsi_trans_complete(trans); @@ -667,30 +641,34 @@ void gsi_trans_complete(struct gsi_trans *trans) void gsi_channel_trans_cancel_pending(struct gsi_channel *channel) { struct gsi_trans_info *trans_info = &channel->trans_info; - struct gsi_trans *trans; - bool cancelled; + u16 trans_id = trans_info->pending_id; /* channel->gsi->mutex is held by caller */ - spin_lock_bh(&trans_info->spinlock); - cancelled = !list_empty(&trans_info->pending); - list_for_each_entry(trans, &trans_info->pending, links) - trans->cancelled = true; + /* If there are no pending transactions, we're done */ + if (trans_id == trans_info->committed_id) + return; - list_splice_tail_init(&trans_info->pending, &trans_info->complete); + /* Mark all pending transactions cancelled */ + do { + struct gsi_trans *trans; - spin_unlock_bh(&trans_info->spinlock); + trans = &trans_info->trans[trans_id % channel->tre_count]; + trans->cancelled = true; + } while (++trans_id != trans_info->committed_id); + + /* All pending transactions are now completed */ + trans_info->pending_id = trans_info->committed_id; /* Schedule NAPI polling to complete the cancelled transactions */ - if (cancelled) - napi_schedule(&channel->napi); + napi_schedule(&channel->napi); } /* Issue a command to read a single byte from a channel */ int gsi_trans_read_byte(struct gsi *gsi, u32 channel_id, dma_addr_t addr) { struct gsi_channel *channel = &gsi->channel[channel_id]; - struct gsi_ring *ring = &channel->tre_ring; + struct gsi_ring *tre_ring = &channel->tre_ring; struct gsi_trans_info *trans_info; struct gsi_tre *dest_tre; @@ -700,12 +678,12 @@ int gsi_trans_read_byte(struct gsi *gsi, u32 channel_id, dma_addr_t addr) if (!gsi_trans_tre_reserve(trans_info, 1)) return -EBUSY; - /* Now fill the the reserved TRE and tell the hardware */ + /* Now fill the reserved TRE and tell the hardware */ - dest_tre = gsi_ring_virt(ring, ring->index); + dest_tre = gsi_ring_virt(tre_ring, tre_ring->index); gsi_trans_tre_fill(dest_tre, addr, 1, true, false, IPA_CMD_NONE); - ring->index++; + tre_ring->index++; gsi_channel_doorbell(channel); return 0; @@ -723,6 +701,7 @@ void gsi_trans_read_byte_done(struct gsi *gsi, u32 channel_id) int gsi_channel_trans_init(struct gsi *gsi, u32 channel_id) { struct gsi_channel *channel = &gsi->channel[channel_id]; + u32 tre_count = channel->tre_count; struct gsi_trans_info *trans_info; u32 tre_max; int ret; @@ -730,68 +709,66 @@ int gsi_channel_trans_init(struct gsi *gsi, u32 channel_id) /* Ensure the size of a channel element is what's expected */ BUILD_BUG_ON(sizeof(struct gsi_tre) != GSI_RING_ELEMENT_SIZE); - /* The map array is used to determine what transaction is associated - * with a TRE that the hardware reports has completed. We need one - * map entry per TRE. - */ trans_info = &channel->trans_info; - trans_info->map = kcalloc(channel->tre_count, sizeof(*trans_info->map), - GFP_KERNEL); - if (!trans_info->map) - return -ENOMEM; - /* We can't use more TREs than there are available in the ring. - * This limits the number of transactions that can be oustanding. - * Worst case is one TRE per transaction (but we actually limit - * it to something a little less than that). We allocate resources - * for transactions (including transaction structures) based on - * this maximum number. + /* The tre_avail field is what ultimately limits the number of + * outstanding transactions and their resources. A transaction + * allocation succeeds only if the TREs available are sufficient + * for what the transaction might need. */ tre_max = gsi_channel_tre_max(channel->gsi, channel_id); + atomic_set(&trans_info->tre_avail, tre_max); - /* Transactions are allocated one at a time. */ - ret = gsi_trans_pool_init(&trans_info->pool, sizeof(struct gsi_trans), - tre_max, 1); - if (ret) - goto err_kfree; + /* We can't use more TREs than the number available in the ring. + * This limits the number of transactions that can be outstanding. + * Worst case is one TRE per transaction (but we actually limit + * it to something a little less than that). By allocating a + * power-of-two number of transactions we can use an index + * modulo that number to determine the next one that's free. + * Transactions are allocated one at a time. + */ + trans_info->trans = kcalloc(tre_count, sizeof(*trans_info->trans), + GFP_KERNEL); + if (!trans_info->trans) + return -ENOMEM; + trans_info->free_id = 0; /* all modulo channel->tre_count */ + trans_info->allocated_id = 0; + trans_info->committed_id = 0; + trans_info->pending_id = 0; + trans_info->completed_id = 0; + trans_info->polled_id = 0; + + /* A completion event contains a pointer to the TRE that caused + * the event (which will be the last one used by the transaction). + * Each entry in this map records the transaction associated + * with a corresponding completed TRE. + */ + trans_info->map = kcalloc(tre_count, sizeof(*trans_info->map), + GFP_KERNEL); + if (!trans_info->map) { + ret = -ENOMEM; + goto err_trans_free; + } /* A transaction uses a scatterlist array to represent the data * transfers implemented by the transaction. Each scatterlist * element is used to fill a single TRE when the transaction is * committed. So we need as many scatterlist elements as the * maximum number of TREs that can be outstanding. - * - * All TREs in a transaction must fit within the channel's TLV FIFO. - * A transaction on a channel can allocate as many TREs as that but - * no more. */ ret = gsi_trans_pool_init(&trans_info->sg_pool, sizeof(struct scatterlist), - tre_max, channel->tlv_count); + tre_max, channel->trans_tre_max); if (ret) - goto err_trans_pool_exit; - - /* Finally, the tre_avail field is what ultimately limits the number - * of outstanding transactions and their resources. A transaction - * allocation succeeds only if the TREs available are sufficient for - * what the transaction might need. Transaction resource pools are - * sized based on the maximum number of outstanding TREs, so there - * will always be resources available if there are TREs available. - */ - atomic_set(&trans_info->tre_avail, tre_max); + goto err_map_free; - spin_lock_init(&trans_info->spinlock); - INIT_LIST_HEAD(&trans_info->alloc); - INIT_LIST_HEAD(&trans_info->pending); - INIT_LIST_HEAD(&trans_info->complete); - INIT_LIST_HEAD(&trans_info->polled); return 0; -err_trans_pool_exit: - gsi_trans_pool_exit(&trans_info->pool); -err_kfree: +err_map_free: kfree(trans_info->map); +err_trans_free: + kfree(trans_info->trans); dev_err(gsi->dev, "error %d initializing channel %u transactions\n", ret, channel_id); @@ -805,6 +782,6 @@ void gsi_channel_trans_exit(struct gsi_channel *channel) struct gsi_trans_info *trans_info = &channel->trans_info; gsi_trans_pool_exit(&trans_info->sg_pool); - gsi_trans_pool_exit(&trans_info->pool); + kfree(trans_info->trans); kfree(trans_info->map); } |