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Diffstat (limited to 'drivers/net/ipa/gsi.h')
| -rw-r--r-- | drivers/net/ipa/gsi.h | 281 |
1 files changed, 281 insertions, 0 deletions
diff --git a/drivers/net/ipa/gsi.h b/drivers/net/ipa/gsi.h new file mode 100644 index 0000000000..42063b227c --- /dev/null +++ b/drivers/net/ipa/gsi.h @@ -0,0 +1,281 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +/* Copyright (c) 2015-2018, The Linux Foundation. All rights reserved. + * Copyright (C) 2018-2023 Linaro Ltd. + */ +#ifndef _GSI_H_ +#define _GSI_H_ + +#include <linux/types.h> +#include <linux/spinlock.h> +#include <linux/mutex.h> +#include <linux/completion.h> +#include <linux/platform_device.h> +#include <linux/netdevice.h> + +#include "ipa_version.h" + +/* Maximum number of channels and event rings supported by the driver */ +#define GSI_CHANNEL_COUNT_MAX 28 +#define GSI_EVT_RING_COUNT_MAX 28 + +/* Maximum TLV FIFO size for a channel; 64 here is arbitrary (and high) */ +#define GSI_TLV_MAX 64 + +struct device; +struct scatterlist; +struct platform_device; + +struct gsi; +struct gsi_trans; +struct gsi_channel_data; +struct ipa_gsi_endpoint_data; + +struct gsi_ring { + void *virt; /* ring array base address */ + dma_addr_t addr; /* primarily low 32 bits used */ + u32 count; /* number of elements in ring */ + + /* The ring index value indicates the next "open" entry in the ring. + * + * A channel ring consists of TRE entries filled by the AP and passed + * to the hardware for processing. For a channel ring, the ring index + * identifies the next unused entry to be filled by the AP. In this + * case the initial value is assumed by hardware to be 0. + * + * An event ring consists of event structures filled by the hardware + * and passed to the AP. For event rings, the ring index identifies + * the next ring entry that is not known to have been filled by the + * hardware. The initial value used is arbitrary (so we use 0). + */ + u32 index; +}; + +/* Transactions use several resources that can be allocated dynamically + * but taken from a fixed-size pool. The number of elements required for + * the pool is limited by the total number of TREs that can be outstanding. + * + * If sufficient TREs are available to reserve for a transaction, + * allocation from these pools is guaranteed to succeed. Furthermore, + * these resources are implicitly freed whenever the TREs in the + * transaction they're associated with are released. + * + * The result of a pool allocation of multiple elements is always + * contiguous. + */ +struct gsi_trans_pool { + void *base; /* base address of element pool */ + u32 count; /* # elements in the pool */ + u32 free; /* next free element in pool (modulo) */ + u32 size; /* size (bytes) of an element */ + u32 max_alloc; /* max allocation request */ + dma_addr_t addr; /* DMA address if DMA pool (or 0) */ +}; + +struct gsi_trans_info { + atomic_t tre_avail; /* TREs available for allocation */ + + u16 free_id; /* first free trans in array */ + u16 allocated_id; /* first allocated transaction */ + u16 committed_id; /* first committed transaction */ + u16 pending_id; /* first pending transaction */ + u16 completed_id; /* first completed transaction */ + u16 polled_id; /* first polled transaction */ + struct gsi_trans *trans; /* transaction array */ + struct gsi_trans **map; /* TRE -> transaction map */ + + struct gsi_trans_pool sg_pool; /* scatterlist pool */ + struct gsi_trans_pool cmd_pool; /* command payload DMA pool */ +}; + +/* Hardware values signifying the state of a channel */ +enum gsi_channel_state { + GSI_CHANNEL_STATE_NOT_ALLOCATED = 0x0, + GSI_CHANNEL_STATE_ALLOCATED = 0x1, + GSI_CHANNEL_STATE_STARTED = 0x2, + GSI_CHANNEL_STATE_STOPPED = 0x3, + GSI_CHANNEL_STATE_STOP_IN_PROC = 0x4, + GSI_CHANNEL_STATE_FLOW_CONTROLLED = 0x5, /* IPA v4.2-v4.9 */ + GSI_CHANNEL_STATE_ERROR = 0xf, +}; + +/* We only care about channels between IPA and AP */ +struct gsi_channel { + struct gsi *gsi; + bool toward_ipa; + bool command; /* AP command TX channel or not */ + + u8 trans_tre_max; /* max TREs in a transaction */ + u16 tre_count; + u16 event_count; + + struct gsi_ring tre_ring; + u32 evt_ring_id; + + /* The following counts are used only for TX endpoints */ + u64 byte_count; /* total # bytes transferred */ + u64 trans_count; /* total # transactions */ + u64 queued_byte_count; /* last reported queued byte count */ + u64 queued_trans_count; /* ...and queued trans count */ + u64 compl_byte_count; /* last reported completed byte count */ + u64 compl_trans_count; /* ...and completed trans count */ + + struct gsi_trans_info trans_info; + + struct napi_struct napi; +}; + +/* Hardware values signifying the state of an event ring */ +enum gsi_evt_ring_state { + GSI_EVT_RING_STATE_NOT_ALLOCATED = 0x0, + GSI_EVT_RING_STATE_ALLOCATED = 0x1, + GSI_EVT_RING_STATE_ERROR = 0xf, +}; + +struct gsi_evt_ring { + struct gsi_channel *channel; + struct gsi_ring ring; +}; + +struct gsi { + struct device *dev; /* Same as IPA device */ + enum ipa_version version; + void __iomem *virt; /* I/O mapped registers */ + const struct regs *regs; + + u32 irq; + u32 channel_count; + u32 evt_ring_count; + u32 event_bitmap; /* allocated event rings */ + u32 modem_channel_bitmap; /* modem channels to allocate */ + u32 type_enabled_bitmap; /* GSI IRQ types enabled */ + u32 ieob_enabled_bitmap; /* IEOB IRQ enabled (event rings) */ + int result; /* Negative errno (generic commands) */ + struct completion completion; /* Signals GSI command completion */ + struct mutex mutex; /* protects commands, programming */ + struct gsi_channel channel[GSI_CHANNEL_COUNT_MAX]; + struct gsi_evt_ring evt_ring[GSI_EVT_RING_COUNT_MAX]; + struct net_device dummy_dev; /* needed for NAPI */ +}; + +/** + * gsi_setup() - Set up the GSI subsystem + * @gsi: Address of GSI structure embedded in an IPA structure + * + * Return: 0 if successful, or a negative error code + * + * Performs initialization that must wait until the GSI hardware is + * ready (including firmware loaded). + */ +int gsi_setup(struct gsi *gsi); + +/** + * gsi_teardown() - Tear down GSI subsystem + * @gsi: GSI address previously passed to a successful gsi_setup() call + */ +void gsi_teardown(struct gsi *gsi); + +/** + * gsi_channel_tre_max() - Channel maximum number of in-flight TREs + * @gsi: GSI pointer + * @channel_id: Channel whose limit is to be returned + * + * Return: The maximum number of TREs outstanding on the channel + */ +u32 gsi_channel_tre_max(struct gsi *gsi, u32 channel_id); + +/** + * gsi_channel_start() - Start an allocated GSI channel + * @gsi: GSI pointer + * @channel_id: Channel to start + * + * Return: 0 if successful, or a negative error code + */ +int gsi_channel_start(struct gsi *gsi, u32 channel_id); + +/** + * gsi_channel_stop() - Stop a started GSI channel + * @gsi: GSI pointer returned by gsi_setup() + * @channel_id: Channel to stop + * + * Return: 0 if successful, or a negative error code + */ +int gsi_channel_stop(struct gsi *gsi, u32 channel_id); + +/** + * gsi_modem_channel_flow_control() - Set channel flow control state (IPA v4.2+) + * @gsi: GSI pointer returned by gsi_setup() + * @channel_id: Modem TX channel to control + * @enable: Whether to enable flow control (i.e., prevent flow) + */ +void gsi_modem_channel_flow_control(struct gsi *gsi, u32 channel_id, + bool enable); + +/** + * gsi_channel_reset() - Reset an allocated GSI channel + * @gsi: GSI pointer + * @channel_id: Channel to be reset + * @doorbell: Whether to (possibly) enable the doorbell engine + * + * Reset a channel and reconfigure it. The @doorbell flag indicates + * that the doorbell engine should be enabled if needed. + * + * GSI hardware relinquishes ownership of all pending receive buffer + * transactions and they will complete with their cancelled flag set. + */ +void gsi_channel_reset(struct gsi *gsi, u32 channel_id, bool doorbell); + +/** + * gsi_suspend() - Prepare the GSI subsystem for suspend + * @gsi: GSI pointer + */ +void gsi_suspend(struct gsi *gsi); + +/** + * gsi_resume() - Resume the GSI subsystem following suspend + * @gsi: GSI pointer + */ +void gsi_resume(struct gsi *gsi); + +/** + * gsi_channel_suspend() - Suspend a GSI channel + * @gsi: GSI pointer + * @channel_id: Channel to suspend + * + * For IPA v4.0+, suspend is implemented by stopping the channel. + */ +int gsi_channel_suspend(struct gsi *gsi, u32 channel_id); + +/** + * gsi_channel_resume() - Resume a suspended GSI channel + * @gsi: GSI pointer + * @channel_id: Channel to resume + * + * For IPA v4.0+, the stopped channel is started again. + */ +int gsi_channel_resume(struct gsi *gsi, u32 channel_id); + +/** + * gsi_init() - Initialize the GSI subsystem + * @gsi: Address of GSI structure embedded in an IPA structure + * @pdev: IPA platform device + * @version: IPA hardware version (implies GSI version) + * @count: Number of entries in the configuration data array + * @data: Endpoint and channel configuration data + * + * Return: 0 if successful, or a negative error code + * + * Early stage initialization of the GSI subsystem, performing tasks + * that can be done before the GSI hardware is ready to use. + */ +int gsi_init(struct gsi *gsi, struct platform_device *pdev, + enum ipa_version version, u32 count, + const struct ipa_gsi_endpoint_data *data); + +/** + * gsi_exit() - Exit the GSI subsystem + * @gsi: GSI address previously passed to a successful gsi_init() call + */ +void gsi_exit(struct gsi *gsi); + +#endif /* _GSI_H_ */ |