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soc: qcom: ipa: GSI transactions
This patch implements GSI transactions. A GSI transaction is a structure that represents a single request (consisting of one or more TREs) sent to the GSI hardware. The last TRE in a transaction includes a flag requesting that the GSI interrupt the AP to notify that it has completed. TREs are executed and completed strictly in order. For this reason, the completion of a single TRE implies that all previous TREs (in particular all of those "earlier" in a transaction) have completed. Whenever there is a need to send a request (a set of TREs) to the IPA, a GSI transaction is allocated, specifying the number of TREs that will be required. Details of the request (e.g. transfer offsets and length) are represented by in a Linux scatterlist array that is incorporated in the transaction structure. Once all commands (TREs) are added to a transaction it is committed. When the hardware signals that the request has completed, a callback function allows for cleanup or followup activity to be performed before the transaction is freed. Signed-off-by: Alex Elder <elder@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Alex Elder
David S. Miller
parent
c3f398b141
commit
9dd441e4ed
786
drivers/net/ipa/gsi_trans.c
Normal file
786
drivers/net/ipa/gsi_trans.c
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@ -0,0 +1,786 @@
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// SPDX-License-Identifier: GPL-2.0
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/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
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* Copyright (C) 2019-2020 Linaro Ltd.
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*/
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#include <linux/types.h>
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#include <linux/bits.h>
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#include <linux/bitfield.h>
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#include <linux/refcount.h>
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#include <linux/scatterlist.h>
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#include <linux/dma-direction.h>
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#include "gsi.h"
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#include "gsi_private.h"
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#include "gsi_trans.h"
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#include "ipa_gsi.h"
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#include "ipa_data.h"
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#include "ipa_cmd.h"
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/**
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* DOC: GSI Transactions
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*
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* A GSI transaction abstracts the behavior of a GSI channel by representing
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* everything about a related group of IPA commands in a single structure.
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* (A "command" in this sense is either a data transfer or an IPA immediate
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* command.) Most details of interaction with the GSI hardware are managed
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* by the GSI transaction core, allowing users to simply describe commands
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* to be performed. When a transaction has completed a callback function
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* (dependent on the type of endpoint associated with the channel) allows
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* cleanup of resources associated with the transaction.
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*
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* To perform a command (or set of them), a user of the GSI transaction
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* interface allocates a transaction, indicating the number of TREs required
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* (one per command). If sufficient TREs are available, they are reserved
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* for use in the transaction and the allocation succeeds. This way
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* exhaustion of the available TREs in a channel ring is detected
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* as early as possible. All resources required to complete a transaction
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* are allocated at transaction allocation time.
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*
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* Commands performed as part of a transaction are represented in an array
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* of Linux scatterlist structures. This array is allocated with the
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* transaction, and its entries are initialized using standard scatterlist
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* functions (such as sg_set_buf() or skb_to_sgvec()).
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*
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* Once a transaction's scatterlist structures have been initialized, the
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* transaction is committed. The caller is responsible for mapping buffers
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* for DMA if necessary, and this should be done *before* allocating
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* the transaction. Between a successful allocation and commit of a
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* transaction no errors should occur.
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*
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* Committing transfers ownership of the entire transaction to the GSI
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* transaction core. The GSI transaction code formats the content of
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* the scatterlist array into the channel ring buffer and informs the
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* hardware that new TREs are available to process.
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*
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* The last TRE in each transaction is marked to interrupt the AP when the
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* GSI hardware has completed it. Because transfers described by TREs are
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* performed strictly in order, signaling the completion of just the last
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* TRE in the transaction is sufficient to indicate the full transaction
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* is complete.
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*
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* When a transaction is complete, ipa_gsi_trans_complete() is called by the
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* GSI code into the IPA layer, allowing it to perform any final cleanup
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* required before the transaction is freed.
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*/
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/* Hardware values representing a transfer element type */
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enum gsi_tre_type {
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GSI_RE_XFER = 0x2,
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GSI_RE_IMMD_CMD = 0x3,
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};
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/* An entry in a channel ring */
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struct gsi_tre {
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__le64 addr; /* DMA address */
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__le16 len_opcode; /* length in bytes or enum IPA_CMD_* */
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__le16 reserved;
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__le32 flags; /* TRE_FLAGS_* */
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};
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/* gsi_tre->flags mask values (in CPU byte order) */
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#define TRE_FLAGS_CHAIN_FMASK GENMASK(0, 0)
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#define TRE_FLAGS_IEOB_FMASK GENMASK(8, 8)
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#define TRE_FLAGS_IEOT_FMASK GENMASK(9, 9)
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#define TRE_FLAGS_BEI_FMASK GENMASK(10, 10)
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#define TRE_FLAGS_TYPE_FMASK GENMASK(23, 16)
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int gsi_trans_pool_init(struct gsi_trans_pool *pool, size_t size, u32 count,
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u32 max_alloc)
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{
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void *virt;
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#ifdef IPA_VALIDATE
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if (!size || size % 8)
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return -EINVAL;
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if (count < max_alloc)
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return -EINVAL;
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if (!max_alloc)
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return -EINVAL;
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#endif /* IPA_VALIDATE */
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/* By allocating a few extra entries in our pool (one less
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* than the maximum number that will be requested in a
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* single allocation), we can always satisfy requests without
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* ever worrying about straddling the end of the pool array.
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* If there aren't enough entries starting at the free index,
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* we just allocate free entries from the beginning of the pool.
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*/
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virt = kcalloc(count + max_alloc - 1, size, GFP_KERNEL);
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if (!virt)
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return -ENOMEM;
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pool->base = virt;
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/* If the allocator gave us any extra memory, use it */
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pool->count = ksize(pool->base) / size;
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pool->free = 0;
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pool->max_alloc = max_alloc;
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pool->size = size;
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pool->addr = 0; /* Only used for DMA pools */
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return 0;
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}
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void gsi_trans_pool_exit(struct gsi_trans_pool *pool)
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{
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kfree(pool->base);
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memset(pool, 0, sizeof(*pool));
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}
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/* Allocate the requested number of (zeroed) entries from the pool */
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/* Home-grown DMA pool. This way we can preallocate and use the tre_count
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* to guarantee allocations will succeed. Even though we specify max_alloc
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* (and it can be more than one), we only allow allocation of a single
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* element from a DMA pool.
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*/
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int gsi_trans_pool_init_dma(struct device *dev, struct gsi_trans_pool *pool,
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size_t size, u32 count, u32 max_alloc)
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{
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size_t total_size;
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dma_addr_t addr;
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void *virt;
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#ifdef IPA_VALIDATE
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if (!size || size % 8)
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return -EINVAL;
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if (count < max_alloc)
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return -EINVAL;
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if (!max_alloc)
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return -EINVAL;
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#endif /* IPA_VALIDATE */
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/* Don't let allocations cross a power-of-two boundary */
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size = __roundup_pow_of_two(size);
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total_size = (count + max_alloc - 1) * size;
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/* The allocator will give us a power-of-2 number of pages. But we
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* can't guarantee that, so request it. That way we won't waste any
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* memory that would be available beyond the required space.
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*/
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total_size = get_order(total_size) << PAGE_SHIFT;
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virt = dma_alloc_coherent(dev, total_size, &addr, GFP_KERNEL);
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if (!virt)
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return -ENOMEM;
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pool->base = virt;
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pool->count = total_size / size;
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pool->free = 0;
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pool->size = size;
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pool->max_alloc = max_alloc;
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pool->addr = addr;
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return 0;
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}
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void gsi_trans_pool_exit_dma(struct device *dev, struct gsi_trans_pool *pool)
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{
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dma_free_coherent(dev, pool->size, pool->base, pool->addr);
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memset(pool, 0, sizeof(*pool));
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}
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/* Return the byte offset of the next free entry in the pool */
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static u32 gsi_trans_pool_alloc_common(struct gsi_trans_pool *pool, u32 count)
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{
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u32 offset;
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/* assert(count > 0); */
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/* assert(count <= pool->max_alloc); */
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/* Allocate from beginning if wrap would occur */
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if (count > pool->count - pool->free)
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pool->free = 0;
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offset = pool->free * pool->size;
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pool->free += count;
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memset(pool->base + offset, 0, count * pool->size);
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return offset;
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}
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/* Allocate a contiguous block of zeroed entries from a pool */
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void *gsi_trans_pool_alloc(struct gsi_trans_pool *pool, u32 count)
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{
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return pool->base + gsi_trans_pool_alloc_common(pool, count);
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}
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/* Allocate a single zeroed entry from a DMA pool */
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void *gsi_trans_pool_alloc_dma(struct gsi_trans_pool *pool, dma_addr_t *addr)
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{
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u32 offset = gsi_trans_pool_alloc_common(pool, 1);
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*addr = pool->addr + offset;
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return pool->base + offset;
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}
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/* Return the pool element that immediately follows the one given.
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* This only works done if elements are allocated one at a time.
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*/
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void *gsi_trans_pool_next(struct gsi_trans_pool *pool, void *element)
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{
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void *end = pool->base + pool->count * pool->size;
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/* assert(element >= pool->base); */
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/* assert(element < end); */
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/* assert(pool->max_alloc == 1); */
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element += pool->size;
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return element < end ? element : pool->base;
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}
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/* Map a given ring entry index to the transaction associated with it */
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static void gsi_channel_trans_map(struct gsi_channel *channel, u32 index,
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struct gsi_trans *trans)
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{
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/* Note: index *must* be used modulo the ring count here */
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channel->trans_info.map[index % channel->tre_ring.count] = trans;
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}
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/* Return the transaction mapped to a given ring entry */
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struct gsi_trans *
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gsi_channel_trans_mapped(struct gsi_channel *channel, u32 index)
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{
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/* Note: index *must* be used modulo the ring count here */
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return channel->trans_info.map[index % channel->tre_ring.count];
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}
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/* Return the oldest completed transaction for a channel (or null) */
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struct gsi_trans *gsi_channel_trans_complete(struct gsi_channel *channel)
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{
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return list_first_entry_or_null(&channel->trans_info.complete,
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struct gsi_trans, links);
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}
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/* Move a transaction from the allocated list to the pending list */
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static void gsi_trans_move_pending(struct gsi_trans *trans)
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{
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struct gsi_channel *channel = &trans->gsi->channel[trans->channel_id];
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struct gsi_trans_info *trans_info = &channel->trans_info;
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spin_lock_bh(&trans_info->spinlock);
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list_move_tail(&trans->links, &trans_info->pending);
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spin_unlock_bh(&trans_info->spinlock);
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}
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/* Move a transaction and all of its predecessors from the pending list
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* to the completed list.
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*/
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void gsi_trans_move_complete(struct gsi_trans *trans)
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{
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struct gsi_channel *channel = &trans->gsi->channel[trans->channel_id];
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struct gsi_trans_info *trans_info = &channel->trans_info;
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struct list_head list;
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spin_lock_bh(&trans_info->spinlock);
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/* Move this transaction and all predecessors to completed list */
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list_cut_position(&list, &trans_info->pending, &trans->links);
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list_splice_tail(&list, &trans_info->complete);
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spin_unlock_bh(&trans_info->spinlock);
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}
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/* Move a transaction from the completed list to the polled list */
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void gsi_trans_move_polled(struct gsi_trans *trans)
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{
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struct gsi_channel *channel = &trans->gsi->channel[trans->channel_id];
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struct gsi_trans_info *trans_info = &channel->trans_info;
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spin_lock_bh(&trans_info->spinlock);
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list_move_tail(&trans->links, &trans_info->polled);
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spin_unlock_bh(&trans_info->spinlock);
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}
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/* Reserve some number of TREs on a channel. Returns true if successful */
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static bool
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gsi_trans_tre_reserve(struct gsi_trans_info *trans_info, u32 tre_count)
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{
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int avail = atomic_read(&trans_info->tre_avail);
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int new;
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do {
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new = avail - (int)tre_count;
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if (unlikely(new < 0))
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return false;
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} while (!atomic_try_cmpxchg(&trans_info->tre_avail, &avail, new));
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return true;
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}
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/* Release previously-reserved TRE entries to a channel */
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static void
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gsi_trans_tre_release(struct gsi_trans_info *trans_info, u32 tre_count)
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{
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atomic_add(tre_count, &trans_info->tre_avail);
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}
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/* Allocate a GSI transaction on a channel */
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struct gsi_trans *gsi_channel_trans_alloc(struct gsi *gsi, u32 channel_id,
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u32 tre_count,
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enum dma_data_direction direction)
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{
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struct gsi_channel *channel = &gsi->channel[channel_id];
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struct gsi_trans_info *trans_info;
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struct gsi_trans *trans;
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/* assert(tre_count <= gsi_channel_trans_tre_max(gsi, channel_id)); */
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trans_info = &channel->trans_info;
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/* We reserve the TREs now, but consume them at commit time.
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* If there aren't enough available, we're done.
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*/
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if (!gsi_trans_tre_reserve(trans_info, tre_count))
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return NULL;
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/* Allocate and initialize non-zero fields in the the transaction */
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trans = gsi_trans_pool_alloc(&trans_info->pool, 1);
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trans->gsi = gsi;
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trans->channel_id = channel_id;
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trans->tre_count = tre_count;
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init_completion(&trans->completion);
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/* Allocate the scatterlist and (if requested) info entries. */
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trans->sgl = gsi_trans_pool_alloc(&trans_info->sg_pool, tre_count);
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sg_init_marker(trans->sgl, tre_count);
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trans->direction = direction;
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spin_lock_bh(&trans_info->spinlock);
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list_add_tail(&trans->links, &trans_info->alloc);
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spin_unlock_bh(&trans_info->spinlock);
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refcount_set(&trans->refcount, 1);
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return trans;
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}
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/* Free a previously-allocated transaction (used only in case of error) */
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void gsi_trans_free(struct gsi_trans *trans)
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{
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struct gsi_trans_info *trans_info;
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if (!refcount_dec_and_test(&trans->refcount))
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return;
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trans_info = &trans->gsi->channel[trans->channel_id].trans_info;
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spin_lock_bh(&trans_info->spinlock);
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list_del(&trans->links);
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spin_unlock_bh(&trans_info->spinlock);
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ipa_gsi_trans_release(trans);
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/* Releasing the reserved TREs implicitly frees the sgl[] and
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* (if present) info[] arrays, plus the transaction itself.
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*/
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gsi_trans_tre_release(trans_info, trans->tre_count);
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}
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/* Add an immediate command to a transaction */
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void gsi_trans_cmd_add(struct gsi_trans *trans, void *buf, u32 size,
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dma_addr_t addr, enum dma_data_direction direction,
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enum ipa_cmd_opcode opcode)
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{
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struct ipa_cmd_info *info;
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u32 which = trans->used++;
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struct scatterlist *sg;
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/* assert(which < trans->tre_count); */
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/* Set the page information for the buffer. We also need to fill in
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* the DMA address for the buffer (something dma_map_sg() normally
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* does).
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*/
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sg = &trans->sgl[which];
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sg_set_buf(sg, buf, size);
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sg_dma_address(sg) = addr;
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info = &trans->info[which];
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info->opcode = opcode;
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info->direction = direction;
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}
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/* Add a page transfer to a transaction. It will fill the only TRE. */
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int gsi_trans_page_add(struct gsi_trans *trans, struct page *page, u32 size,
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u32 offset)
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{
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struct scatterlist *sg = &trans->sgl[0];
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int ret;
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/* assert(trans->tre_count == 1); */
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/* assert(!trans->used); */
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sg_set_page(sg, page, size, offset);
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ret = dma_map_sg(trans->gsi->dev, sg, 1, trans->direction);
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if (!ret)
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return -ENOMEM;
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trans->used++; /* Transaction now owns the (DMA mapped) page */
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return 0;
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}
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/* Add an SKB transfer to a transaction. No other TREs will be used. */
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int gsi_trans_skb_add(struct gsi_trans *trans, struct sk_buff *skb)
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{
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struct scatterlist *sg = &trans->sgl[0];
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u32 used;
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int ret;
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/* assert(trans->tre_count == 1); */
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/* assert(!trans->used); */
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/* skb->len will not be 0 (checked early) */
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ret = skb_to_sgvec(skb, sg, 0, skb->len);
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if (ret < 0)
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return ret;
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used = ret;
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||||
ret = dma_map_sg(trans->gsi->dev, sg, used, trans->direction);
|
||||
if (!ret)
|
||||
return -ENOMEM;
|
||||
|
||||
trans->used += used; /* Transaction now owns the (DMA mapped) skb */
|
||||
|
||||
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 the
|
||||
* pending list. 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;
|
||||
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;
|
||||
u32 avail;
|
||||
u32 i;
|
||||
|
||||
/* assert(trans->used > 0); */
|
||||
|
||||
/* 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;
|
||||
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;
|
||||
|
||||
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 last TRE with the transaction */
|
||||
gsi_channel_trans_map(channel, ring->index - 1, trans);
|
||||
|
||||
gsi_trans_move_pending(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_channel_doorbell(channel);
|
||||
}
|
||||
}
|
||||
|
||||
/* Commit a GSI transaction */
|
||||
void gsi_trans_commit(struct gsi_trans *trans, bool ring_db)
|
||||
{
|
||||
if (trans->used)
|
||||
__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)
|
||||
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);
|
||||
}
|
||||
|
||||
/* 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,
|
||||
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;
|
||||
struct gsi_trans *trans;
|
||||
bool cancelled;
|
||||
|
||||
/* 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;
|
||||
|
||||
list_splice_tail_init(&trans_info->pending, &trans_info->complete);
|
||||
|
||||
spin_unlock_bh(&trans_info->spinlock);
|
||||
|
||||
/* Schedule NAPI polling to complete the cancelled transactions */
|
||||
if (cancelled)
|
||||
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_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 the reserved TRE and tell the hardware */
|
||||
|
||||
dest_tre = gsi_ring_virt(ring, ring->index);
|
||||
gsi_trans_tre_fill(dest_tre, addr, 1, true, false, IPA_CMD_NONE);
|
||||
|
||||
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];
|
||||
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);
|
||||
|
||||
/* 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.
|
||||
*/
|
||||
tre_max = gsi_channel_tre_max(channel->gsi, channel_id);
|
||||
|
||||
/* 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;
|
||||
|
||||
/* 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);
|
||||
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);
|
||||
|
||||
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:
|
||||
kfree(trans_info->map);
|
||||
|
||||
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);
|
||||
gsi_trans_pool_exit(&trans_info->pool);
|
||||
kfree(trans_info->map);
|
||||
}
|
||||
226
drivers/net/ipa/gsi_trans.h
Normal file
226
drivers/net/ipa/gsi_trans.h
Normal file
@ -0,0 +1,226 @@
|
||||
/* SPDX-License-Identifier: GPL-2.0 */
|
||||
|
||||
/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
|
||||
* Copyright (C) 2019-2020 Linaro Ltd.
|
||||
*/
|
||||
#ifndef _GSI_TRANS_H_
|
||||
#define _GSI_TRANS_H_
|
||||
|
||||
#include <linux/types.h>
|
||||
#include <linux/refcount.h>
|
||||
#include <linux/completion.h>
|
||||
#include <linux/dma-direction.h>
|
||||
|
||||
#include "ipa_cmd.h"
|
||||
|
||||
struct scatterlist;
|
||||
struct device;
|
||||
struct sk_buff;
|
||||
|
||||
struct gsi;
|
||||
struct gsi_trans;
|
||||
struct gsi_trans_pool;
|
||||
|
||||
/**
|
||||
* struct gsi_trans - a GSI transaction
|
||||
*
|
||||
* Most fields in this structure for internal use by the transaction core code:
|
||||
* @links: Links for channel transaction lists by state
|
||||
* @gsi: GSI pointer
|
||||
* @channel_id: Channel number transaction is associated with
|
||||
* @cancelled: If set by the core code, transaction was cancelled
|
||||
* @tre_count: Number of TREs reserved for this transaction
|
||||
* @used: Number of TREs *used* (could be less than tre_count)
|
||||
* @len: Total # of transfer bytes represented in sgl[] (set by core)
|
||||
* @data: Preserved but not touched by the core transaction code
|
||||
* @sgl: An array of scatter/gather entries managed by core code
|
||||
* @info: Array of command information structures (command channel)
|
||||
* @direction: DMA transfer direction (DMA_NONE for commands)
|
||||
* @refcount: Reference count used for destruction
|
||||
* @completion: Completed when the transaction completes
|
||||
* @byte_count: TX channel byte count recorded when transaction committed
|
||||
* @trans_count: Channel transaction count when committed (for BQL accounting)
|
||||
*
|
||||
* The size used for some fields in this structure were chosen to ensure
|
||||
* the full structure size is no larger than 128 bytes.
|
||||
*/
|
||||
struct gsi_trans {
|
||||
struct list_head links; /* gsi_channel lists */
|
||||
|
||||
struct gsi *gsi;
|
||||
u8 channel_id;
|
||||
|
||||
bool cancelled; /* true if transaction was cancelled */
|
||||
|
||||
u8 tre_count; /* # TREs requested */
|
||||
u8 used; /* # entries used in sgl[] */
|
||||
u32 len; /* total # bytes across sgl[] */
|
||||
|
||||
void *data;
|
||||
struct scatterlist *sgl;
|
||||
struct ipa_cmd_info *info; /* array of entries, or null */
|
||||
enum dma_data_direction direction;
|
||||
|
||||
refcount_t refcount;
|
||||
struct completion completion;
|
||||
|
||||
u64 byte_count; /* channel byte_count when committed */
|
||||
u64 trans_count; /* channel trans_count when committed */
|
||||
};
|
||||
|
||||
/**
|
||||
* gsi_trans_pool_init() - Initialize a pool of structures for transactions
|
||||
* @gsi: GSI pointer
|
||||
* @size: Size of elements in the pool
|
||||
* @count: Minimum number of elements in the pool
|
||||
* @max_alloc: Maximum number of elements allocated at a time from pool
|
||||
*
|
||||
* @Return: 0 if successful, or a negative error code
|
||||
*/
|
||||
int gsi_trans_pool_init(struct gsi_trans_pool *pool, size_t size, u32 count,
|
||||
u32 max_alloc);
|
||||
|
||||
/**
|
||||
* gsi_trans_pool_alloc() - Allocate one or more elements from a pool
|
||||
* @pool: Pool pointer
|
||||
* @count: Number of elements to allocate from the pool
|
||||
*
|
||||
* @Return: Virtual address of element(s) allocated from the pool
|
||||
*/
|
||||
void *gsi_trans_pool_alloc(struct gsi_trans_pool *pool, u32 count);
|
||||
|
||||
/**
|
||||
* gsi_trans_pool_exit() - Inverse of gsi_trans_pool_init()
|
||||
* @pool: Pool pointer
|
||||
*/
|
||||
void gsi_trans_pool_exit(struct gsi_trans_pool *pool);
|
||||
|
||||
/**
|
||||
* gsi_trans_pool_init_dma() - Initialize a pool of DMA-able structures
|
||||
* @dev: Device used for DMA
|
||||
* @pool: Pool pointer
|
||||
* @size: Size of elements in the pool
|
||||
* @count: Minimum number of elements in the pool
|
||||
* @max_alloc: Maximum number of elements allocated at a time from pool
|
||||
*
|
||||
* @Return: 0 if successful, or a negative error code
|
||||
*
|
||||
* Structures in this pool reside in DMA-coherent memory.
|
||||
*/
|
||||
int gsi_trans_pool_init_dma(struct device *dev, struct gsi_trans_pool *pool,
|
||||
size_t size, u32 count, u32 max_alloc);
|
||||
|
||||
/**
|
||||
* gsi_trans_pool_alloc_dma() - Allocate an element from a DMA pool
|
||||
* @pool: DMA pool pointer
|
||||
* @addr: DMA address "handle" associated with the allocation
|
||||
*
|
||||
* @Return: Virtual address of element allocated from the pool
|
||||
*
|
||||
* Only one element at a time may be allocated from a DMA pool.
|
||||
*/
|
||||
void *gsi_trans_pool_alloc_dma(struct gsi_trans_pool *pool, dma_addr_t *addr);
|
||||
|
||||
/**
|
||||
* gsi_trans_pool_exit() - Inverse of gsi_trans_pool_init()
|
||||
* @pool: Pool pointer
|
||||
*/
|
||||
void gsi_trans_pool_exit_dma(struct device *dev, struct gsi_trans_pool *pool);
|
||||
|
||||
/**
|
||||
* gsi_channel_trans_alloc() - Allocate a GSI transaction on a channel
|
||||
* @gsi: GSI pointer
|
||||
* @channel_id: Channel the transaction is associated with
|
||||
* @tre_count: Number of elements in the transaction
|
||||
* @direction: DMA direction for entire SGL (or DMA_NONE)
|
||||
*
|
||||
* @Return: A GSI transaction structure, or a null pointer if all
|
||||
* available transactions are in use
|
||||
*/
|
||||
struct gsi_trans *gsi_channel_trans_alloc(struct gsi *gsi, u32 channel_id,
|
||||
u32 tre_count,
|
||||
enum dma_data_direction direction);
|
||||
|
||||
/**
|
||||
* gsi_trans_free() - Free a previously-allocated GSI transaction
|
||||
* @trans: Transaction to be freed
|
||||
*/
|
||||
void gsi_trans_free(struct gsi_trans *trans);
|
||||
|
||||
/**
|
||||
* gsi_trans_cmd_add() - Add an immediate command to a transaction
|
||||
* @trans: Transaction
|
||||
* @buf: Buffer pointer for command payload
|
||||
* @size: Number of bytes in buffer
|
||||
* @addr: DMA address for payload
|
||||
* @direction: Direction of DMA transfer (or DMA_NONE if none required)
|
||||
* @opcode: IPA immediate command opcode
|
||||
*/
|
||||
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);
|
||||
|
||||
/**
|
||||
* gsi_trans_page_add() - Add a page transfer to a transaction
|
||||
* @trans: Transaction
|
||||
* @page: Page pointer
|
||||
* @size: Number of bytes (starting at offset) to transfer
|
||||
* @offset: Offset within page for start of transfer
|
||||
*/
|
||||
int gsi_trans_page_add(struct gsi_trans *trans, struct page *page, u32 size,
|
||||
u32 offset);
|
||||
|
||||
/**
|
||||
* gsi_trans_skb_add() - Add a socket transfer to a transaction
|
||||
* @trans: Transaction
|
||||
* @skb: Socket buffer for transfer (outbound)
|
||||
*
|
||||
* @Return: 0, or -EMSGSIZE if socket data won't fit in transaction.
|
||||
*/
|
||||
int gsi_trans_skb_add(struct gsi_trans *trans, struct sk_buff *skb);
|
||||
|
||||
/**
|
||||
* gsi_trans_commit() - Commit a GSI transaction
|
||||
* @trans: Transaction to commit
|
||||
* @ring_db: Whether to tell the hardware about these queued transfers
|
||||
*/
|
||||
void gsi_trans_commit(struct gsi_trans *trans, bool ring_db);
|
||||
|
||||
/**
|
||||
* gsi_trans_commit_wait() - Commit a GSI transaction and wait for it
|
||||
* to complete
|
||||
* @trans: Transaction to commit
|
||||
*/
|
||||
void gsi_trans_commit_wait(struct gsi_trans *trans);
|
||||
|
||||
/**
|
||||
* gsi_trans_commit_wait_timeout() - Commit a GSI transaction and wait for
|
||||
* it to complete, with timeout
|
||||
* @trans: Transaction to commit
|
||||
* @timeout: Timeout period (in milliseconds)
|
||||
*/
|
||||
int gsi_trans_commit_wait_timeout(struct gsi_trans *trans,
|
||||
unsigned long timeout);
|
||||
|
||||
/**
|
||||
* gsi_trans_read_byte() - Issue a single byte read TRE on a channel
|
||||
* @gsi: GSI pointer
|
||||
* @channel_id: Channel on which to read a byte
|
||||
* @addr: DMA address into which to transfer the one byte
|
||||
*
|
||||
* This is not a transaction operation at all. It's defined here because
|
||||
* it needs to be done in coordination with other transaction activity.
|
||||
*/
|
||||
int gsi_trans_read_byte(struct gsi *gsi, u32 channel_id, dma_addr_t addr);
|
||||
|
||||
/**
|
||||
* gsi_trans_read_byte_done() - Clean up after a single byte read TRE
|
||||
* @gsi: GSI pointer
|
||||
* @channel_id: Channel on which byte was read
|
||||
*
|
||||
* This function needs to be called to signal that the work related
|
||||
* to reading a byte initiated by gsi_trans_read_byte() is complete.
|
||||
*/
|
||||
void gsi_trans_read_byte_done(struct gsi *gsi, u32 channel_id);
|
||||
|
||||
#endif /* _GSI_TRANS_H_ */
|
||||
Loading…
Reference in New Issue
Block a user