1 /* SPDX-License-Identifier: GPL-2.0 */ 2 3 /* Copyright (c) 2015-2018, The Linux Foundation. All rights reserved. 4 * Copyright (C) 2018-2021 Linaro Ltd. 5 */ 6 #ifndef _GSI_H_ 7 #define _GSI_H_ 8 9 #include <linux/types.h> 10 #include <linux/spinlock.h> 11 #include <linux/mutex.h> 12 #include <linux/completion.h> 13 #include <linux/platform_device.h> 14 #include <linux/netdevice.h> 15 16 #include "ipa_version.h" 17 18 /* Maximum number of channels and event rings supported by the driver */ 19 #define GSI_CHANNEL_COUNT_MAX 23 20 #define GSI_EVT_RING_COUNT_MAX 24 21 22 /* Maximum TLV FIFO size for a channel; 64 here is arbitrary (and high) */ 23 #define GSI_TLV_MAX 64 24 25 struct device; 26 struct scatterlist; 27 struct platform_device; 28 29 struct gsi; 30 struct gsi_trans; 31 struct gsi_channel_data; 32 struct ipa_gsi_endpoint_data; 33 34 /* Execution environment IDs */ 35 enum gsi_ee_id { 36 GSI_EE_AP = 0x0, 37 GSI_EE_MODEM = 0x1, 38 GSI_EE_UC = 0x2, 39 GSI_EE_TZ = 0x3, 40 }; 41 42 struct gsi_ring { 43 void *virt; /* ring array base address */ 44 dma_addr_t addr; /* primarily low 32 bits used */ 45 u32 count; /* number of elements in ring */ 46 47 /* The ring index value indicates the next "open" entry in the ring. 48 * 49 * A channel ring consists of TRE entries filled by the AP and passed 50 * to the hardware for processing. For a channel ring, the ring index 51 * identifies the next unused entry to be filled by the AP. 52 * 53 * An event ring consists of event structures filled by the hardware 54 * and passed to the AP. For event rings, the ring index identifies 55 * the next ring entry that is not known to have been filled by the 56 * hardware. 57 */ 58 u32 index; 59 }; 60 61 /* Transactions use several resources that can be allocated dynamically 62 * but taken from a fixed-size pool. The number of elements required for 63 * the pool is limited by the total number of TREs that can be outstanding. 64 * 65 * If sufficient TREs are available to reserve for a transaction, 66 * allocation from these pools is guaranteed to succeed. Furthermore, 67 * these resources are implicitly freed whenever the TREs in the 68 * transaction they're associated with are released. 69 * 70 * The result of a pool allocation of multiple elements is always 71 * contiguous. 72 */ 73 struct gsi_trans_pool { 74 void *base; /* base address of element pool */ 75 u32 count; /* # elements in the pool */ 76 u32 free; /* next free element in pool (modulo) */ 77 u32 size; /* size (bytes) of an element */ 78 u32 max_alloc; /* max allocation request */ 79 dma_addr_t addr; /* DMA address if DMA pool (or 0) */ 80 }; 81 82 struct gsi_trans_info { 83 atomic_t tre_avail; /* TREs available for allocation */ 84 struct gsi_trans_pool pool; /* transaction pool */ 85 struct gsi_trans_pool sg_pool; /* scatterlist pool */ 86 struct gsi_trans_pool cmd_pool; /* command payload DMA pool */ 87 struct gsi_trans **map; /* TRE -> transaction map */ 88 89 spinlock_t spinlock; /* protects updates to the lists */ 90 struct list_head alloc; /* allocated, not committed */ 91 struct list_head pending; /* committed, awaiting completion */ 92 struct list_head complete; /* completed, awaiting poll */ 93 struct list_head polled; /* returned by gsi_channel_poll_one() */ 94 }; 95 96 /* Hardware values signifying the state of a channel */ 97 enum gsi_channel_state { 98 GSI_CHANNEL_STATE_NOT_ALLOCATED = 0x0, 99 GSI_CHANNEL_STATE_ALLOCATED = 0x1, 100 GSI_CHANNEL_STATE_STARTED = 0x2, 101 GSI_CHANNEL_STATE_STOPPED = 0x3, 102 GSI_CHANNEL_STATE_STOP_IN_PROC = 0x4, 103 GSI_CHANNEL_STATE_FLOW_CONTROLLED = 0x5, /* IPA v4.2-v4.9 */ 104 GSI_CHANNEL_STATE_ERROR = 0xf, 105 }; 106 107 /* We only care about channels between IPA and AP */ 108 struct gsi_channel { 109 struct gsi *gsi; 110 bool toward_ipa; 111 bool command; /* AP command TX channel or not */ 112 113 u8 tlv_count; /* # entries in TLV FIFO */ 114 u16 tre_count; 115 u16 event_count; 116 117 struct gsi_ring tre_ring; 118 u32 evt_ring_id; 119 120 u64 byte_count; /* total # bytes transferred */ 121 u64 trans_count; /* total # transactions */ 122 /* The following counts are used only for TX endpoints */ 123 u64 queued_byte_count; /* last reported queued byte count */ 124 u64 queued_trans_count; /* ...and queued trans count */ 125 u64 compl_byte_count; /* last reported completed byte count */ 126 u64 compl_trans_count; /* ...and completed trans count */ 127 128 struct gsi_trans_info trans_info; 129 130 struct napi_struct napi; 131 }; 132 133 /* Hardware values signifying the state of an event ring */ 134 enum gsi_evt_ring_state { 135 GSI_EVT_RING_STATE_NOT_ALLOCATED = 0x0, 136 GSI_EVT_RING_STATE_ALLOCATED = 0x1, 137 GSI_EVT_RING_STATE_ERROR = 0xf, 138 }; 139 140 struct gsi_evt_ring { 141 struct gsi_channel *channel; 142 struct gsi_ring ring; 143 }; 144 145 struct gsi { 146 struct device *dev; /* Same as IPA device */ 147 enum ipa_version version; 148 void __iomem *virt_raw; /* I/O mapped address range */ 149 void __iomem *virt; /* Adjusted for most registers */ 150 u32 irq; 151 u32 channel_count; 152 u32 evt_ring_count; 153 u32 event_bitmap; /* allocated event rings */ 154 u32 modem_channel_bitmap; /* modem channels to allocate */ 155 u32 type_enabled_bitmap; /* GSI IRQ types enabled */ 156 u32 ieob_enabled_bitmap; /* IEOB IRQ enabled (event rings) */ 157 int result; /* Negative errno (generic commands) */ 158 struct completion completion; /* Signals GSI command completion */ 159 struct mutex mutex; /* protects commands, programming */ 160 struct gsi_channel channel[GSI_CHANNEL_COUNT_MAX]; 161 struct gsi_evt_ring evt_ring[GSI_EVT_RING_COUNT_MAX]; 162 struct net_device dummy_dev; /* needed for NAPI */ 163 }; 164 165 /** 166 * gsi_setup() - Set up the GSI subsystem 167 * @gsi: Address of GSI structure embedded in an IPA structure 168 * 169 * Return: 0 if successful, or a negative error code 170 * 171 * Performs initialization that must wait until the GSI hardware is 172 * ready (including firmware loaded). 173 */ 174 int gsi_setup(struct gsi *gsi); 175 176 /** 177 * gsi_teardown() - Tear down GSI subsystem 178 * @gsi: GSI address previously passed to a successful gsi_setup() call 179 */ 180 void gsi_teardown(struct gsi *gsi); 181 182 /** 183 * gsi_channel_tre_max() - Channel maximum number of in-flight TREs 184 * @gsi: GSI pointer 185 * @channel_id: Channel whose limit is to be returned 186 * 187 * Return: The maximum number of TREs oustanding on the channel 188 */ 189 u32 gsi_channel_tre_max(struct gsi *gsi, u32 channel_id); 190 191 /** 192 * gsi_channel_trans_tre_max() - Maximum TREs in a single transaction 193 * @gsi: GSI pointer 194 * @channel_id: Channel whose limit is to be returned 195 * 196 * Return: The maximum TRE count per transaction on the channel 197 */ 198 u32 gsi_channel_trans_tre_max(struct gsi *gsi, u32 channel_id); 199 200 /** 201 * gsi_channel_start() - Start an allocated GSI channel 202 * @gsi: GSI pointer 203 * @channel_id: Channel to start 204 * 205 * Return: 0 if successful, or a negative error code 206 */ 207 int gsi_channel_start(struct gsi *gsi, u32 channel_id); 208 209 /** 210 * gsi_channel_stop() - Stop a started GSI channel 211 * @gsi: GSI pointer returned by gsi_setup() 212 * @channel_id: Channel to stop 213 * 214 * Return: 0 if successful, or a negative error code 215 */ 216 int gsi_channel_stop(struct gsi *gsi, u32 channel_id); 217 218 /** 219 * gsi_modem_channel_flow_control() - Set channel flow control state (IPA v4.2+) 220 * @gsi: GSI pointer returned by gsi_setup() 221 * @channel_id: Modem TX channel to control 222 * @enable: Whether to enable flow control (i.e., prevent flow) 223 */ 224 void gsi_modem_channel_flow_control(struct gsi *gsi, u32 channel_id, 225 bool enable); 226 227 /** 228 * gsi_channel_reset() - Reset an allocated GSI channel 229 * @gsi: GSI pointer 230 * @channel_id: Channel to be reset 231 * @doorbell: Whether to (possibly) enable the doorbell engine 232 * 233 * Reset a channel and reconfigure it. The @doorbell flag indicates 234 * that the doorbell engine should be enabled if needed. 235 * 236 * GSI hardware relinquishes ownership of all pending receive buffer 237 * transactions and they will complete with their cancelled flag set. 238 */ 239 void gsi_channel_reset(struct gsi *gsi, u32 channel_id, bool doorbell); 240 241 /** 242 * gsi_suspend() - Prepare the GSI subsystem for suspend 243 * @gsi: GSI pointer 244 */ 245 void gsi_suspend(struct gsi *gsi); 246 247 /** 248 * gsi_resume() - Resume the GSI subsystem following suspend 249 * @gsi: GSI pointer 250 */ 251 void gsi_resume(struct gsi *gsi); 252 253 /** 254 * gsi_channel_suspend() - Suspend a GSI channel 255 * @gsi: GSI pointer 256 * @channel_id: Channel to suspend 257 * 258 * For IPA v4.0+, suspend is implemented by stopping the channel. 259 */ 260 int gsi_channel_suspend(struct gsi *gsi, u32 channel_id); 261 262 /** 263 * gsi_channel_resume() - Resume a suspended GSI channel 264 * @gsi: GSI pointer 265 * @channel_id: Channel to resume 266 * 267 * For IPA v4.0+, the stopped channel is started again. 268 */ 269 int gsi_channel_resume(struct gsi *gsi, u32 channel_id); 270 271 /** 272 * gsi_init() - Initialize the GSI subsystem 273 * @gsi: Address of GSI structure embedded in an IPA structure 274 * @pdev: IPA platform device 275 * @version: IPA hardware version (implies GSI version) 276 * @count: Number of entries in the configuration data array 277 * @data: Endpoint and channel configuration data 278 * 279 * Return: 0 if successful, or a negative error code 280 * 281 * Early stage initialization of the GSI subsystem, performing tasks 282 * that can be done before the GSI hardware is ready to use. 283 */ 284 int gsi_init(struct gsi *gsi, struct platform_device *pdev, 285 enum ipa_version version, u32 count, 286 const struct ipa_gsi_endpoint_data *data); 287 288 /** 289 * gsi_exit() - Exit the GSI subsystem 290 * @gsi: GSI address previously passed to a successful gsi_init() call 291 */ 292 void gsi_exit(struct gsi *gsi); 293 294 #endif /* _GSI_H_ */ 295