diff options
author | Alex Elder <elder@linaro.org> | 2020-03-06 07:28:23 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2020-03-09 08:07:10 +0300 |
commit | 9dd441e4ed5755c2a74c206bd9bc50a431b1689b (patch) | |
tree | 687681876d6de6d6490dbc4fc39718a30c8be6a7 /drivers/net/ipa/gsi_trans.h | |
parent | c3f398b141a8d80e502d36ad56102608f3031aa3 (diff) | |
download | linux-9dd441e4ed5755c2a74c206bd9bc50a431b1689b.tar.xz |
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>
Diffstat (limited to 'drivers/net/ipa/gsi_trans.h')
-rw-r--r-- | drivers/net/ipa/gsi_trans.h | 226 |
1 files changed, 226 insertions, 0 deletions
diff --git a/drivers/net/ipa/gsi_trans.h b/drivers/net/ipa/gsi_trans.h new file mode 100644 index 000000000000..1477fc15b30a --- /dev/null +++ b/drivers/net/ipa/gsi_trans.h @@ -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_ */ |