diff options
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/bus/Kconfig | 1 | ||||
-rw-r--r-- | drivers/bus/Makefile | 3 | ||||
-rw-r--r-- | drivers/bus/mhi/Kconfig | 14 | ||||
-rw-r--r-- | drivers/bus/mhi/Makefile | 2 | ||||
-rw-r--r-- | drivers/bus/mhi/core/Makefile | 3 | ||||
-rw-r--r-- | drivers/bus/mhi/core/init.c | 402 | ||||
-rw-r--r-- | drivers/bus/mhi/core/internal.h | 151 |
7 files changed, 576 insertions, 0 deletions
diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig index 6095b6df8a81..6d4e4497b59b 100644 --- a/drivers/bus/Kconfig +++ b/drivers/bus/Kconfig @@ -201,5 +201,6 @@ config DA8XX_MSTPRI peripherals. source "drivers/bus/fsl-mc/Kconfig" +source "drivers/bus/mhi/Kconfig" endmenu diff --git a/drivers/bus/Makefile b/drivers/bus/Makefile index 1320bcf9fa9d..05f32cd694a4 100644 --- a/drivers/bus/Makefile +++ b/drivers/bus/Makefile @@ -34,3 +34,6 @@ obj-$(CONFIG_UNIPHIER_SYSTEM_BUS) += uniphier-system-bus.o obj-$(CONFIG_VEXPRESS_CONFIG) += vexpress-config.o obj-$(CONFIG_DA8XX_MSTPRI) += da8xx-mstpri.o + +# MHI +obj-$(CONFIG_MHI_BUS) += mhi/ diff --git a/drivers/bus/mhi/Kconfig b/drivers/bus/mhi/Kconfig new file mode 100644 index 000000000000..a8bd9bd7db7c --- /dev/null +++ b/drivers/bus/mhi/Kconfig @@ -0,0 +1,14 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# MHI bus +# +# Copyright (c) 2018-2020, The Linux Foundation. All rights reserved. +# + +config MHI_BUS + tristate "Modem Host Interface (MHI) bus" + help + Bus driver for MHI protocol. Modem Host Interface (MHI) is a + communication protocol used by the host processors to control + and communicate with modem devices over a high speed peripheral + bus or shared memory. diff --git a/drivers/bus/mhi/Makefile b/drivers/bus/mhi/Makefile new file mode 100644 index 000000000000..19e6443b72df --- /dev/null +++ b/drivers/bus/mhi/Makefile @@ -0,0 +1,2 @@ +# core layer +obj-y += core/ diff --git a/drivers/bus/mhi/core/Makefile b/drivers/bus/mhi/core/Makefile new file mode 100644 index 000000000000..2db32697c67f --- /dev/null +++ b/drivers/bus/mhi/core/Makefile @@ -0,0 +1,3 @@ +obj-$(CONFIG_MHI_BUS) := mhi.o + +mhi-y := init.o diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c new file mode 100644 index 000000000000..6f24c21284ec --- /dev/null +++ b/drivers/bus/mhi/core/init.c @@ -0,0 +1,402 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved. + * + */ + +#include <linux/device.h> +#include <linux/dma-direction.h> +#include <linux/dma-mapping.h> +#include <linux/interrupt.h> +#include <linux/list.h> +#include <linux/mhi.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/vmalloc.h> +#include <linux/wait.h> +#include "internal.h" + +static int parse_ev_cfg(struct mhi_controller *mhi_cntrl, + struct mhi_controller_config *config) +{ + struct mhi_event *mhi_event; + struct mhi_event_config *event_cfg; + struct device *dev = &mhi_cntrl->mhi_dev->dev; + int i, num; + + num = config->num_events; + mhi_cntrl->total_ev_rings = num; + mhi_cntrl->mhi_event = kcalloc(num, sizeof(*mhi_cntrl->mhi_event), + GFP_KERNEL); + if (!mhi_cntrl->mhi_event) + return -ENOMEM; + + /* Populate event ring */ + mhi_event = mhi_cntrl->mhi_event; + for (i = 0; i < num; i++) { + event_cfg = &config->event_cfg[i]; + + mhi_event->er_index = i; + mhi_event->ring.elements = event_cfg->num_elements; + mhi_event->intmod = event_cfg->irq_moderation_ms; + mhi_event->irq = event_cfg->irq; + + if (event_cfg->channel != U32_MAX) { + /* This event ring has a dedicated channel */ + mhi_event->chan = event_cfg->channel; + if (mhi_event->chan >= mhi_cntrl->max_chan) { + dev_err(dev, + "Event Ring channel not available\n"); + goto error_ev_cfg; + } + + mhi_event->mhi_chan = + &mhi_cntrl->mhi_chan[mhi_event->chan]; + } + + /* Priority is fixed to 1 for now */ + mhi_event->priority = 1; + + mhi_event->db_cfg.brstmode = event_cfg->mode; + if (MHI_INVALID_BRSTMODE(mhi_event->db_cfg.brstmode)) + goto error_ev_cfg; + + mhi_event->data_type = event_cfg->data_type; + + mhi_event->hw_ring = event_cfg->hardware_event; + if (mhi_event->hw_ring) + mhi_cntrl->hw_ev_rings++; + else + mhi_cntrl->sw_ev_rings++; + + mhi_event->cl_manage = event_cfg->client_managed; + mhi_event->offload_ev = event_cfg->offload_channel; + mhi_event++; + } + + /* We need IRQ for each event ring + additional one for BHI */ + mhi_cntrl->nr_irqs_req = mhi_cntrl->total_ev_rings + 1; + + return 0; + +error_ev_cfg: + + kfree(mhi_cntrl->mhi_event); + return -EINVAL; +} + +static int parse_ch_cfg(struct mhi_controller *mhi_cntrl, + struct mhi_controller_config *config) +{ + struct mhi_channel_config *ch_cfg; + struct device *dev = &mhi_cntrl->mhi_dev->dev; + int i; + u32 chan; + + mhi_cntrl->max_chan = config->max_channels; + + /* + * The allocation of MHI channels can exceed 32KB in some scenarios, + * so to avoid any memory possible allocation failures, vzalloc is + * used here + */ + mhi_cntrl->mhi_chan = vzalloc(mhi_cntrl->max_chan * + sizeof(*mhi_cntrl->mhi_chan)); + if (!mhi_cntrl->mhi_chan) + return -ENOMEM; + + INIT_LIST_HEAD(&mhi_cntrl->lpm_chans); + + /* Populate channel configurations */ + for (i = 0; i < config->num_channels; i++) { + struct mhi_chan *mhi_chan; + + ch_cfg = &config->ch_cfg[i]; + + chan = ch_cfg->num; + if (chan >= mhi_cntrl->max_chan) { + dev_err(dev, "Channel %d not available\n", chan); + goto error_chan_cfg; + } + + mhi_chan = &mhi_cntrl->mhi_chan[chan]; + mhi_chan->name = ch_cfg->name; + mhi_chan->chan = chan; + + mhi_chan->tre_ring.elements = ch_cfg->num_elements; + if (!mhi_chan->tre_ring.elements) + goto error_chan_cfg; + + /* + * For some channels, local ring length should be bigger than + * the transfer ring length due to internal logical channels + * in device. So host can queue much more buffers than transfer + * ring length. Example, RSC channels should have a larger local + * channel length than transfer ring length. + */ + mhi_chan->buf_ring.elements = ch_cfg->local_elements; + if (!mhi_chan->buf_ring.elements) + mhi_chan->buf_ring.elements = mhi_chan->tre_ring.elements; + mhi_chan->er_index = ch_cfg->event_ring; + mhi_chan->dir = ch_cfg->dir; + + /* + * For most channels, chtype is identical to channel directions. + * So, if it is not defined then assign channel direction to + * chtype + */ + mhi_chan->type = ch_cfg->type; + if (!mhi_chan->type) + mhi_chan->type = (enum mhi_ch_type)mhi_chan->dir; + + mhi_chan->ee_mask = ch_cfg->ee_mask; + mhi_chan->db_cfg.pollcfg = ch_cfg->pollcfg; + mhi_chan->lpm_notify = ch_cfg->lpm_notify; + mhi_chan->offload_ch = ch_cfg->offload_channel; + mhi_chan->db_cfg.reset_req = ch_cfg->doorbell_mode_switch; + mhi_chan->pre_alloc = ch_cfg->auto_queue; + mhi_chan->auto_start = ch_cfg->auto_start; + + /* + * If MHI host allocates buffers, then the channel direction + * should be DMA_FROM_DEVICE + */ + if (mhi_chan->pre_alloc && mhi_chan->dir != DMA_FROM_DEVICE) { + dev_err(dev, "Invalid channel configuration\n"); + goto error_chan_cfg; + } + + /* + * Bi-directional and direction less channel must be an + * offload channel + */ + if ((mhi_chan->dir == DMA_BIDIRECTIONAL || + mhi_chan->dir == DMA_NONE) && !mhi_chan->offload_ch) { + dev_err(dev, "Invalid channel configuration\n"); + goto error_chan_cfg; + } + + if (!mhi_chan->offload_ch) { + mhi_chan->db_cfg.brstmode = ch_cfg->doorbell; + if (MHI_INVALID_BRSTMODE(mhi_chan->db_cfg.brstmode)) { + dev_err(dev, "Invalid Door bell mode\n"); + goto error_chan_cfg; + } + } + + mhi_chan->configured = true; + + if (mhi_chan->lpm_notify) + list_add_tail(&mhi_chan->node, &mhi_cntrl->lpm_chans); + } + + return 0; + +error_chan_cfg: + vfree(mhi_cntrl->mhi_chan); + + return -EINVAL; +} + +static int parse_config(struct mhi_controller *mhi_cntrl, + struct mhi_controller_config *config) +{ + int ret; + + /* Parse MHI channel configuration */ + ret = parse_ch_cfg(mhi_cntrl, config); + if (ret) + return ret; + + /* Parse MHI event configuration */ + ret = parse_ev_cfg(mhi_cntrl, config); + if (ret) + goto error_ev_cfg; + + mhi_cntrl->timeout_ms = config->timeout_ms; + if (!mhi_cntrl->timeout_ms) + mhi_cntrl->timeout_ms = MHI_TIMEOUT_MS; + + mhi_cntrl->bounce_buf = config->use_bounce_buf; + mhi_cntrl->buffer_len = config->buf_len; + if (!mhi_cntrl->buffer_len) + mhi_cntrl->buffer_len = MHI_MAX_MTU; + + return 0; + +error_ev_cfg: + vfree(mhi_cntrl->mhi_chan); + + return ret; +} + +int mhi_register_controller(struct mhi_controller *mhi_cntrl, + struct mhi_controller_config *config) +{ + int ret; + int i; + struct mhi_event *mhi_event; + struct mhi_chan *mhi_chan; + struct mhi_cmd *mhi_cmd; + struct mhi_device *mhi_dev; + + if (!mhi_cntrl) + return -EINVAL; + + if (!mhi_cntrl->runtime_get || !mhi_cntrl->runtime_put) + return -EINVAL; + + if (!mhi_cntrl->status_cb || !mhi_cntrl->link_status) + return -EINVAL; + + ret = parse_config(mhi_cntrl, config); + if (ret) + return -EINVAL; + + mhi_cntrl->mhi_cmd = kcalloc(NR_OF_CMD_RINGS, + sizeof(*mhi_cntrl->mhi_cmd), GFP_KERNEL); + if (!mhi_cntrl->mhi_cmd) { + ret = -ENOMEM; + goto error_alloc_cmd; + } + + INIT_LIST_HEAD(&mhi_cntrl->transition_list); + spin_lock_init(&mhi_cntrl->transition_lock); + spin_lock_init(&mhi_cntrl->wlock); + init_waitqueue_head(&mhi_cntrl->state_event); + + mhi_cmd = mhi_cntrl->mhi_cmd; + for (i = 0; i < NR_OF_CMD_RINGS; i++, mhi_cmd++) + spin_lock_init(&mhi_cmd->lock); + + mhi_event = mhi_cntrl->mhi_event; + for (i = 0; i < mhi_cntrl->total_ev_rings; i++, mhi_event++) { + /* Skip for offload events */ + if (mhi_event->offload_ev) + continue; + + mhi_event->mhi_cntrl = mhi_cntrl; + spin_lock_init(&mhi_event->lock); + } + + mhi_chan = mhi_cntrl->mhi_chan; + for (i = 0; i < mhi_cntrl->max_chan; i++, mhi_chan++) { + mutex_init(&mhi_chan->mutex); + init_completion(&mhi_chan->completion); + rwlock_init(&mhi_chan->lock); + } + + /* Register controller with MHI bus */ + mhi_dev = mhi_alloc_device(mhi_cntrl); + if (IS_ERR(mhi_dev)) { + dev_err(mhi_cntrl->cntrl_dev, "Failed to allocate MHI device\n"); + ret = PTR_ERR(mhi_dev); + goto error_alloc_dev; + } + + mhi_dev->dev_type = MHI_DEVICE_CONTROLLER; + mhi_dev->mhi_cntrl = mhi_cntrl; + dev_set_name(&mhi_dev->dev, "%s", dev_name(mhi_cntrl->cntrl_dev)); + + /* Init wakeup source */ + device_init_wakeup(&mhi_dev->dev, true); + + ret = device_add(&mhi_dev->dev); + if (ret) + goto error_add_dev; + + mhi_cntrl->mhi_dev = mhi_dev; + + return 0; + +error_add_dev: + put_device(&mhi_dev->dev); + +error_alloc_dev: + kfree(mhi_cntrl->mhi_cmd); + +error_alloc_cmd: + vfree(mhi_cntrl->mhi_chan); + kfree(mhi_cntrl->mhi_event); + + return ret; +} +EXPORT_SYMBOL_GPL(mhi_register_controller); + +void mhi_unregister_controller(struct mhi_controller *mhi_cntrl) +{ + struct mhi_device *mhi_dev = mhi_cntrl->mhi_dev; + struct mhi_chan *mhi_chan = mhi_cntrl->mhi_chan; + unsigned int i; + + kfree(mhi_cntrl->mhi_cmd); + kfree(mhi_cntrl->mhi_event); + + /* Drop the references to MHI devices created for channels */ + for (i = 0; i < mhi_cntrl->max_chan; i++, mhi_chan++) { + if (!mhi_chan->mhi_dev) + continue; + + put_device(&mhi_chan->mhi_dev->dev); + } + vfree(mhi_cntrl->mhi_chan); + + device_del(&mhi_dev->dev); + put_device(&mhi_dev->dev); +} +EXPORT_SYMBOL_GPL(mhi_unregister_controller); + +static void mhi_release_device(struct device *dev) +{ + struct mhi_device *mhi_dev = to_mhi_device(dev); + + kfree(mhi_dev); +} + +struct mhi_device *mhi_alloc_device(struct mhi_controller *mhi_cntrl) +{ + struct mhi_device *mhi_dev; + struct device *dev; + + mhi_dev = kzalloc(sizeof(*mhi_dev), GFP_KERNEL); + if (!mhi_dev) + return ERR_PTR(-ENOMEM); + + dev = &mhi_dev->dev; + device_initialize(dev); + dev->bus = &mhi_bus_type; + dev->release = mhi_release_device; + dev->parent = mhi_cntrl->cntrl_dev; + mhi_dev->mhi_cntrl = mhi_cntrl; + mhi_dev->dev_wake = 0; + + return mhi_dev; +} + +static int mhi_match(struct device *dev, struct device_driver *drv) +{ + return 0; +}; + +struct bus_type mhi_bus_type = { + .name = "mhi", + .dev_name = "mhi", + .match = mhi_match, +}; + +static int __init mhi_init(void) +{ + return bus_register(&mhi_bus_type); +} + +static void __exit mhi_exit(void) +{ + bus_unregister(&mhi_bus_type); +} + +postcore_initcall(mhi_init); +module_exit(mhi_exit); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("MHI Host Interface"); diff --git a/drivers/bus/mhi/core/internal.h b/drivers/bus/mhi/core/internal.h new file mode 100644 index 000000000000..6af59ac3ec9d --- /dev/null +++ b/drivers/bus/mhi/core/internal.h @@ -0,0 +1,151 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (c) 2018-2020, The Linux Foundation. All rights reserved. + * + */ + +#ifndef _MHI_INT_H +#define _MHI_INT_H + +#include <linux/mhi.h> + +extern struct bus_type mhi_bus_type; + +/* MHI transfer completion events */ +enum mhi_ev_ccs { + MHI_EV_CC_INVALID = 0x0, + MHI_EV_CC_SUCCESS = 0x1, + MHI_EV_CC_EOT = 0x2, /* End of transfer event */ + MHI_EV_CC_OVERFLOW = 0x3, + MHI_EV_CC_EOB = 0x4, /* End of block event */ + MHI_EV_CC_OOB = 0x5, /* Out of block event */ + MHI_EV_CC_DB_MODE = 0x6, + MHI_EV_CC_UNDEFINED_ERR = 0x10, + MHI_EV_CC_BAD_TRE = 0x11, +}; + +enum mhi_ch_state { + MHI_CH_STATE_DISABLED = 0x0, + MHI_CH_STATE_ENABLED = 0x1, + MHI_CH_STATE_RUNNING = 0x2, + MHI_CH_STATE_SUSPENDED = 0x3, + MHI_CH_STATE_STOP = 0x4, + MHI_CH_STATE_ERROR = 0x5, +}; + +#define MHI_INVALID_BRSTMODE(mode) (mode != MHI_DB_BRST_DISABLE && \ + mode != MHI_DB_BRST_ENABLE) + +#define NR_OF_CMD_RINGS 1 +#define CMD_EL_PER_RING 128 +#define PRIMARY_CMD_RING 0 +#define MHI_MAX_MTU 0xffff + +enum mhi_er_type { + MHI_ER_TYPE_INVALID = 0x0, + MHI_ER_TYPE_VALID = 0x1, +}; + +struct db_cfg { + bool reset_req; + bool db_mode; + u32 pollcfg; + enum mhi_db_brst_mode brstmode; + dma_addr_t db_val; + void (*process_db)(struct mhi_controller *mhi_cntrl, + struct db_cfg *db_cfg, void __iomem *io_addr, + dma_addr_t db_val); +}; + +struct mhi_ring { + dma_addr_t dma_handle; + dma_addr_t iommu_base; + u64 *ctxt_wp; /* point to ctxt wp */ + void *pre_aligned; + void *base; + void *rp; + void *wp; + size_t el_size; + size_t len; + size_t elements; + size_t alloc_size; + void __iomem *db_addr; +}; + +struct mhi_cmd { + struct mhi_ring ring; + spinlock_t lock; +}; + +struct mhi_buf_info { + void *v_addr; + void *bb_addr; + void *wp; + void *cb_buf; + dma_addr_t p_addr; + size_t len; + enum dma_data_direction dir; +}; + +struct mhi_event { + struct mhi_controller *mhi_cntrl; + struct mhi_chan *mhi_chan; /* dedicated to channel */ + u32 er_index; + u32 intmod; + u32 irq; + int chan; /* this event ring is dedicated to a channel (optional) */ + u32 priority; + enum mhi_er_data_type data_type; + struct mhi_ring ring; + struct db_cfg db_cfg; + struct tasklet_struct task; + spinlock_t lock; + int (*process_event)(struct mhi_controller *mhi_cntrl, + struct mhi_event *mhi_event, + u32 event_quota); + bool hw_ring; + bool cl_manage; + bool offload_ev; /* managed by a device driver */ +}; + +struct mhi_chan { + const char *name; + /* + * Important: When consuming, increment tre_ring first and when + * releasing, decrement buf_ring first. If tre_ring has space, buf_ring + * is guranteed to have space so we do not need to check both rings. + */ + struct mhi_ring buf_ring; + struct mhi_ring tre_ring; + u32 chan; + u32 er_index; + u32 intmod; + enum mhi_ch_type type; + enum dma_data_direction dir; + struct db_cfg db_cfg; + enum mhi_ch_ee_mask ee_mask; + enum mhi_ch_state ch_state; + enum mhi_ev_ccs ccs; + struct mhi_device *mhi_dev; + void (*xfer_cb)(struct mhi_device *mhi_dev, struct mhi_result *result); + struct mutex mutex; + struct completion completion; + rwlock_t lock; + struct list_head node; + bool lpm_notify; + bool configured; + bool offload_ch; + bool pre_alloc; + bool auto_start; + bool wake_capable; +}; + +/* Default MHI timeout */ +#define MHI_TIMEOUT_MS (1000) + +struct mhi_device *mhi_alloc_device(struct mhi_controller *mhi_cntrl); + +int mhi_destroy_device(struct device *dev, void *data); +void mhi_create_devices(struct mhi_controller *mhi_cntrl); + +#endif /* _MHI_INT_H */ |