blob: 0f52c068c46d635954e78c1796b1c63041cdd36b [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
* Copyright (C) 2019-2022 Linaro Ltd.
*/
#include <linux/types.h>
#include <linux/bits.h>
#include <linux/bitfield.h>
#include <linux/refcount.h>
#include <linux/scatterlist.h>
#include <linux/dma-direction.h>
#include "gsi.h"
#include "gsi_private.h"
#include "gsi_trans.h"
#include "ipa_gsi.h"
#include "ipa_data.h"
#include "ipa_cmd.h"
/**
* DOC: GSI Transactions
*
* A GSI transaction abstracts the behavior of a GSI channel by representing
* 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 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 an operation (or set of them), a user of the GSI transaction
* interface allocates a transaction, indicating the number of TREs required
* (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. Any other resources that might be needed to complete a
* transaction are also allocated when the transaction is allocated.
*
* 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 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
* performed strictly in order, signaling the completion of just the last
* TRE in the transaction is sufficient to indicate the full transaction
* is complete.
*
* When a transaction is complete, ipa_gsi_trans_complete() is called by the
* GSI code into the IPA layer, allowing it to perform any final cleanup
* required before the transaction is freed.
*/
/* Hardware values representing a transfer element type */
enum gsi_tre_type {
GSI_RE_XFER = 0x2,
GSI_RE_IMMD_CMD = 0x3,
};
/* An entry in a channel ring */
struct gsi_tre {
__le64 addr; /* DMA address */
__le16 len_opcode; /* length in bytes or enum IPA_CMD_* */
__le16 reserved;
__le32 flags; /* TRE_FLAGS_* */
};
/* gsi_tre->flags mask values (in CPU byte order) */
#define TRE_FLAGS_CHAIN_FMASK GENMASK(0, 0)
#define TRE_FLAGS_IEOT_FMASK GENMASK(9, 9)
#define TRE_FLAGS_BEI_FMASK GENMASK(10, 10)
#define TRE_FLAGS_TYPE_FMASK GENMASK(23, 16)
int gsi_trans_pool_init(struct gsi_trans_pool *pool, size_t size, u32 count,
u32 max_alloc)
{
size_t alloc_size;
void *virt;
if (!size)
return -EINVAL;
if (count < max_alloc)
return -EINVAL;
if (!max_alloc)
return -EINVAL;
/* By allocating a few extra entries in our pool (one less
* than the maximum number that will be requested in a
* single allocation), we can always satisfy requests without
* ever worrying about straddling the end of the pool array.
* If there aren't enough entries starting at the free index,
* we just allocate free entries from the beginning of the pool.
*/
alloc_size = size_mul(count + max_alloc - 1, size);
alloc_size = kmalloc_size_roundup(alloc_size);
virt = kzalloc(alloc_size, GFP_KERNEL);
if (!virt)
return -ENOMEM;
pool->base = virt;
/* If the allocator gave us any extra memory, use it */
pool->count = alloc_size / size;
pool->free = 0;
pool->max_alloc = max_alloc;
pool->size = size;
pool->addr = 0; /* Only used for DMA pools */
return 0;
}
void gsi_trans_pool_exit(struct gsi_trans_pool *pool)
{
kfree(pool->base);
memset(pool, 0, sizeof(*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)
{
size_t total_size;
dma_addr_t addr;
void *virt;
if (!size)
return -EINVAL;
if (count < max_alloc)
return -EINVAL;
if (!max_alloc)
return -EINVAL;
/* Don't let allocations cross a power-of-two boundary */
size = __roundup_pow_of_two(size);
total_size = (count + max_alloc - 1) * size;
/* The allocator will give us a power-of-2 number of pages
* sufficient to satisfy our request. Round up our requested
* size to avoid any unused space in the allocation. This way
* gsi_trans_pool_exit_dma() can assume the total allocated
* size is exactly (count * size).
*/
total_size = get_order(total_size) << PAGE_SHIFT;
virt = dma_alloc_coherent(dev, total_size, &addr, GFP_KERNEL);
if (!virt)
return -ENOMEM;
pool->base = virt;
pool->count = total_size / size;
pool->free = 0;
pool->size = size;
pool->max_alloc = max_alloc;
pool->addr = addr;
return 0;
}
void gsi_trans_pool_exit_dma(struct device *dev, struct gsi_trans_pool *pool)
{
size_t total_size = pool->count * pool->size;
dma_free_coherent(dev, total_size, pool->base, pool->addr);
memset(pool, 0, sizeof(*pool));
}
/* Return the byte offset of the next free entry in the pool */
static u32 gsi_trans_pool_alloc_common(struct gsi_trans_pool *pool, u32 count)
{
u32 offset;
WARN_ON(!count);
WARN_ON(count > pool->max_alloc);
/* Allocate from beginning if wrap would occur */
if (count > pool->count - pool->free)
pool->free = 0;
offset = pool->free * pool->size;
pool->free += count;
memset(pool->base + offset, 0, count * pool->size);
return offset;
}
/* Allocate a contiguous block of zeroed entries from a pool */
void *gsi_trans_pool_alloc(struct gsi_trans_pool *pool, u32 count)
{
return pool->base + gsi_trans_pool_alloc_common(pool, count);
}
/* Allocate a single zeroed entry from a DMA pool */
void *gsi_trans_pool_alloc_dma(struct gsi_trans_pool *pool, dma_addr_t *addr)
{
u32 offset = gsi_trans_pool_alloc_common(pool, 1);
*addr = pool->addr + offset;
return pool->base + offset;
}
/* Map a TRE ring entry index to the transaction it is associated with */
static void gsi_trans_map(struct gsi_trans *trans, u32 index)
{
struct gsi_channel *channel = &trans->gsi->channel[trans->channel_id];
/* The completion event will indicate the last TRE used */
index += trans->used_count - 1;
/* Note: index *must* be used modulo the ring count here */
channel->trans_info.map[index % channel->tre_ring.count] = trans;
}
/* Return the transaction mapped to a given ring entry */
struct gsi_trans *
gsi_channel_trans_mapped(struct gsi_channel *channel, u32 index)
{
/* Note: index *must* be used modulo the ring count here */
return channel->trans_info.map[index % channel->tre_ring.count];
}
/* Return the oldest completed transaction for a channel (or null) */
struct gsi_trans *gsi_channel_trans_complete(struct gsi_channel *channel)
{
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 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;
/* This allocated transaction is now committed */
trans_info->allocated_id++;
}
/* 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;
/* These committed transactions are now pending */
delta = trans_index - trans_info->committed_id + 1;
trans_info->committed_id += delta % channel->tre_count;
}
/* 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;
u16 trans_index = trans - trans_info->trans;
u16 delta;
/* 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 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;
/* This completed transaction is now polled */
trans_info->completed_id++;
}
/* Reserve some number of TREs on a channel. Returns true if successful */
static bool
gsi_trans_tre_reserve(struct gsi_trans_info *trans_info, u32 tre_count)
{
int avail = atomic_read(&trans_info->tre_avail);
int new;
do {
new = avail - (int)tre_count;
if (unlikely(new < 0))
return false;
} while (!atomic_try_cmpxchg(&trans_info->tre_avail, &avail, new));
return true;
}
/* Release previously-reserved TRE entries to a channel */
static void
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,
enum dma_data_direction direction)
{
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 > channel->trans_tre_max))
return NULL;
trans_info = &channel->trans_info;
/* If we can't reserve the TREs for the transaction, we're done */
if (!gsi_trans_tre_reserve(trans_info, tre_count))
return NULL;
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->rsvd_count = tre_count;
init_completion(&trans->completion);
/* 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;
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)
{
struct gsi_trans_info *trans_info;
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);
}
/* 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->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 ipa_cmd_opcode opcode)
{
u32 which = trans->used_count++;
struct scatterlist *sg;
WARN_ON(which >= trans->rsvd_count);
/* Commands are quite different from data transfer requests.
* Their payloads come from a pool whose memory is allocated
* using dma_alloc_coherent(). We therefore do *not* map them
* for DMA (unlike what we do for pages and skbs).
*
* When a transaction completes, the SGL is normally unmapped.
* A command transaction has direction DMA_NONE, which tells
* gsi_trans_complete() to skip the unmapping step.
*
* The only things we use directly in a command scatter/gather
* entry are the DMA address and length. We still need the SG
* table flags to be maintained though, so assign a NULL page
* pointer for that purpose.
*/
sg = &trans->sgl[which];
sg_assign_page(sg, NULL);
sg_dma_address(sg) = addr;
sg_dma_len(sg) = size;
trans->cmd_opcode[which] = opcode;
}
/* Add a page transfer to a transaction. It will fill the only TRE. */
int gsi_trans_page_add(struct gsi_trans *trans, struct page *page, u32 size,
u32 offset)
{
struct scatterlist *sg = &trans->sgl[0];
int ret;
if (WARN_ON(trans->rsvd_count != 1))
return -EINVAL;
if (WARN_ON(trans->used_count))
return -EINVAL;
sg_set_page(sg, page, size, offset);
ret = dma_map_sg(trans->gsi->dev, sg, 1, trans->direction);
if (!ret)
return -ENOMEM;
trans->used_count++; /* Transaction now owns the (DMA mapped) page */
return 0;
}
/* Add an SKB transfer to a transaction. No other TREs will be used. */
int gsi_trans_skb_add(struct gsi_trans *trans, struct sk_buff *skb)
{
struct scatterlist *sg = &trans->sgl[0];
u32 used_count;
int ret;
if (WARN_ON(trans->rsvd_count != 1))
return -EINVAL;
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_count = ret;
ret = dma_map_sg(trans->gsi->dev, sg, used_count, trans->direction);
if (!ret)
return -ENOMEM;
/* Transaction now owns the (DMA mapped) skb */
trans->used_count += used_count;
return 0;
}
/* Compute the length/opcode value to use for a TRE */
static __le16 gsi_tre_len_opcode(enum ipa_cmd_opcode opcode, u32 len)
{
return opcode == IPA_CMD_NONE ? cpu_to_le16((u16)len)
: cpu_to_le16((u16)opcode);
}
/* Compute the flags value to use for a given TRE */
static __le32 gsi_tre_flags(bool last_tre, bool bei, enum ipa_cmd_opcode opcode)
{
enum gsi_tre_type tre_type;
u32 tre_flags;
tre_type = opcode == IPA_CMD_NONE ? GSI_RE_XFER : GSI_RE_IMMD_CMD;
tre_flags = u32_encode_bits(tre_type, TRE_FLAGS_TYPE_FMASK);
/* Last TRE contains interrupt flags */
if (last_tre) {
/* All transactions end in a transfer completion interrupt */
tre_flags |= TRE_FLAGS_IEOT_FMASK;
/* Don't interrupt when outbound commands are acknowledged */
if (bei)
tre_flags |= TRE_FLAGS_BEI_FMASK;
} else { /* All others indicate there's more to come */
tre_flags |= TRE_FLAGS_CHAIN_FMASK;
}
return cpu_to_le32(tre_flags);
}
static void gsi_trans_tre_fill(struct gsi_tre *dest_tre, dma_addr_t addr,
u32 len, bool last_tre, bool bei,
enum ipa_cmd_opcode opcode)
{
struct gsi_tre tre;
tre.addr = cpu_to_le64(addr);
tre.len_opcode = gsi_tre_len_opcode(opcode, len);
tre.reserved = 0;
tre.flags = gsi_tre_flags(last_tre, bei, opcode);
/* ARM64 can write 16 bytes as a unit with a single instruction.
* Doing the assignment this way is an attempt to make that happen.
*/
*dest_tre = tre;
}
/**
* __gsi_trans_commit() - Common GSI transaction commit code
* @trans: Transaction to commit
* @ring_db: Whether to tell the hardware about these queued transfers
*
* 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
* 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 *tre_ring = &channel->tre_ring;
enum ipa_cmd_opcode opcode = IPA_CMD_NONE;
bool bei = channel->toward_ipa;
struct gsi_tre *dest_tre;
struct scatterlist *sg;
u32 byte_count = 0;
u8 *cmd_opcode;
u32 avail;
u32 i;
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.
*/
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(tre_ring, 0);
if (cmd_opcode)
opcode = *cmd_opcode++;
gsi_trans_tre_fill(dest_tre, addr, len, last_tre, bei, opcode);
dest_tre++;
}
/* Associate the TRE with the transaction */
gsi_trans_map(trans, tre_ring->index);
tre_ring->index += trans->used_count;
trans->len = byte_count;
if (channel->toward_ipa)
gsi_trans_tx_committed(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_trans_tx_queued(trans);
gsi_trans_move_pending(trans);
gsi_channel_doorbell(channel);
}
}
/* Commit a GSI transaction */
void gsi_trans_commit(struct gsi_trans *trans, bool ring_db)
{
if (trans->used_count)
__gsi_trans_commit(trans, ring_db);
else
gsi_trans_free(trans);
}
/* Commit a GSI transaction and wait for it to complete */
void gsi_trans_commit_wait(struct gsi_trans *trans)
{
if (!trans->used_count)
goto out_trans_free;
refcount_inc(&trans->refcount);
__gsi_trans_commit(trans, true);
wait_for_completion(&trans->completion);
out_trans_free:
gsi_trans_free(trans);
}
/* 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_count,
trans->direction);
ipa_gsi_trans_complete(trans);
complete(&trans->completion);
gsi_trans_free(trans);
}
/* Cancel a channel's pending transactions */
void gsi_channel_trans_cancel_pending(struct gsi_channel *channel)
{
struct gsi_trans_info *trans_info = &channel->trans_info;
u16 trans_id = trans_info->pending_id;
/* channel->gsi->mutex is held by caller */
/* If there are no pending transactions, we're done */
if (trans_id == trans_info->committed_id)
return;
/* Mark all pending transactions cancelled */
do {
struct gsi_trans *trans;
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 */
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 *tre_ring = &channel->tre_ring;
struct gsi_trans_info *trans_info;
struct gsi_tre *dest_tre;
trans_info = &channel->trans_info;
/* First reserve the TRE, if possible */
if (!gsi_trans_tre_reserve(trans_info, 1))
return -EBUSY;
/* Now fill the reserved TRE and tell the hardware */
dest_tre = gsi_ring_virt(tre_ring, tre_ring->index);
gsi_trans_tre_fill(dest_tre, addr, 1, true, false, IPA_CMD_NONE);
tre_ring->index++;
gsi_channel_doorbell(channel);
return 0;
}
/* Mark a gsi_trans_read_byte() request done */
void gsi_trans_read_byte_done(struct gsi *gsi, u32 channel_id)
{
struct gsi_channel *channel = &gsi->channel[channel_id];
gsi_trans_tre_release(&channel->trans_info, 1);
}
/* Initialize a channel's GSI transaction info */
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;
/* Ensure the size of a channel element is what's expected */
BUILD_BUG_ON(sizeof(struct gsi_tre) != GSI_RING_ELEMENT_SIZE);
trans_info = &channel->trans_info;
/* 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);
/* 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.
*/
ret = gsi_trans_pool_init(&trans_info->sg_pool,
sizeof(struct scatterlist),
tre_max, channel->trans_tre_max);
if (ret)
goto err_map_free;
return 0;
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);
return ret;
}
/* Inverse of gsi_channel_trans_init() */
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);
kfree(trans_info->trans);
kfree(trans_info->map);
}