/* SPDX-License-Identifier: GPL-2.0 */ /* Copyright (c) 2015-2018, The Linux Foundation. All rights reserved. * Copyright (C) 2018-2024 Linaro Ltd. */ #ifndef _GSI_H_ #define _GSI_H_ #include <linux/completion.h> #include <linux/mutex.h> #include <linux/netdevice.h> #include <linux/types.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 platform_device; struct gsi; struct gsi_trans; 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_ */
