Add support for transferring data between external modem and host processor using MHI protocol. This is based on the patch submitted by Sujeev Dias: https://lkml.org/lkml/2018/7/9/988 Signed-off-by: Sujeev Dias <sdias@xxxxxxxxxxxxxx> Signed-off-by: Siddartha Mohanadoss <smohanad@xxxxxxxxxxxxxx> [mani: splitted the data transfer patch and cleaned up for upstream] Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> --- drivers/bus/mhi/core/init.c | 162 ++++++- drivers/bus/mhi/core/internal.h | 33 ++ drivers/bus/mhi/core/main.c | 777 +++++++++++++++++++++++++++++++- drivers/bus/mhi/core/pm.c | 40 ++ include/linux/mhi.h | 55 +++ 5 files changed, 1058 insertions(+), 9 deletions(-) diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c index 1b5169e20e2b..4d0e5bbb3389 100644 --- a/drivers/bus/mhi/core/init.c +++ b/drivers/bus/mhi/core/init.c @@ -493,6 +493,73 @@ int mhi_init_mmio(struct mhi_controller *mhi_cntrl) return 0; } +void mhi_deinit_chan_ctxt(struct mhi_controller *mhi_cntrl, + struct mhi_chan *mhi_chan) +{ + struct mhi_ring *buf_ring; + struct mhi_ring *tre_ring; + struct mhi_chan_ctxt *chan_ctxt; + + buf_ring = &mhi_chan->buf_ring; + tre_ring = &mhi_chan->tre_ring; + chan_ctxt = &mhi_cntrl->mhi_ctxt->chan_ctxt[mhi_chan->chan]; + + mhi_free_coherent(mhi_cntrl, tre_ring->alloc_size, + tre_ring->pre_aligned, tre_ring->dma_handle); + vfree(buf_ring->base); + + buf_ring->base = tre_ring->base = NULL; + chan_ctxt->rbase = 0; +} + +int mhi_init_chan_ctxt(struct mhi_controller *mhi_cntrl, + struct mhi_chan *mhi_chan) +{ + struct mhi_ring *buf_ring; + struct mhi_ring *tre_ring; + struct mhi_chan_ctxt *chan_ctxt; + u32 tmp; + int ret; + + buf_ring = &mhi_chan->buf_ring; + tre_ring = &mhi_chan->tre_ring; + tre_ring->el_size = sizeof(struct mhi_tre); + tre_ring->len = tre_ring->el_size * tre_ring->elements; + chan_ctxt = &mhi_cntrl->mhi_ctxt->chan_ctxt[mhi_chan->chan]; + ret = mhi_alloc_aligned_ring(mhi_cntrl, tre_ring, tre_ring->len); + if (ret) + return -ENOMEM; + + buf_ring->el_size = sizeof(struct mhi_buf_info); + buf_ring->len = buf_ring->el_size * buf_ring->elements; + buf_ring->base = vzalloc(buf_ring->len); + + if (!buf_ring->base) { + mhi_free_coherent(mhi_cntrl, tre_ring->alloc_size, + tre_ring->pre_aligned, tre_ring->dma_handle); + return -ENOMEM; + } + + tmp = chan_ctxt->chcfg; + tmp &= ~CHAN_CTX_CHSTATE_MASK; + tmp |= (MHI_CH_STATE_ENABLED << CHAN_CTX_CHSTATE_SHIFT); + chan_ctxt->chcfg = tmp; + + chan_ctxt->rbase = tre_ring->iommu_base; + chan_ctxt->rp = chan_ctxt->wp = chan_ctxt->rbase; + chan_ctxt->rlen = tre_ring->len; + tre_ring->ctxt_wp = &chan_ctxt->wp; + + tre_ring->rp = tre_ring->wp = tre_ring->base; + buf_ring->rp = buf_ring->wp = buf_ring->base; + mhi_chan->db_cfg.db_mode = 1; + + /* Update to all cores */ + smp_wmb(); + + return 0; +} + static int parse_ev_cfg(struct mhi_controller *mhi_cntrl, struct mhi_controller_config *config) { @@ -648,6 +715,31 @@ static int parse_ch_cfg(struct mhi_controller *mhi_cntrl, mhi_chan->db_cfg.pollcfg = ch_cfg->pollcfg; mhi_chan->xfer_type = ch_cfg->data_type; + switch (mhi_chan->xfer_type) { + case MHI_BUF_RAW: + mhi_chan->gen_tre = mhi_gen_tre; + mhi_chan->queue_xfer = mhi_queue_buf; + break; + case MHI_BUF_SKB: + mhi_chan->queue_xfer = mhi_queue_skb; + break; + case MHI_BUF_SCLIST: + mhi_chan->gen_tre = mhi_gen_tre; + mhi_chan->queue_xfer = mhi_queue_sclist; + break; + case MHI_BUF_NOP: + mhi_chan->queue_xfer = mhi_queue_nop; + break; + case MHI_BUF_DMA: + case MHI_BUF_RSC_DMA: + mhi_chan->queue_xfer = mhi_queue_dma; + break; + default: + dev_err(mhi_cntrl->dev, + "Channel datatype not supported\n"); + goto error_chan_cfg; + } + 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; @@ -677,6 +769,13 @@ static int parse_ch_cfg(struct mhi_controller *mhi_cntrl, goto error_chan_cfg; } + /* + * If MHI host pre-allocates buffers then client drivers + * cannot queue + */ + if (mhi_chan->pre_alloc) + mhi_chan->queue_xfer = mhi_queue_nop; + if (!mhi_chan->offload_ch) { mhi_chan->db_cfg.brstmode = ch_cfg->doorbell; if (MHI_INVALID_BRSTMODE(mhi_chan->db_cfg.brstmode)) { @@ -809,6 +908,14 @@ int mhi_register_controller(struct mhi_controller *mhi_cntrl, rwlock_init(&mhi_chan->lock); } + if (mhi_cntrl->bounce_buf) { + mhi_cntrl->map_single = mhi_map_single_use_bb; + mhi_cntrl->unmap_single = mhi_unmap_single_use_bb; + } else { + mhi_cntrl->map_single = mhi_map_single_no_bb; + mhi_cntrl->unmap_single = mhi_unmap_single_no_bb; + } + /* Register controller with MHI bus */ mhi_dev = mhi_alloc_device(mhi_cntrl); if (IS_ERR(mhi_dev)) { @@ -974,6 +1081,14 @@ static int mhi_driver_probe(struct device *dev) struct mhi_event *mhi_event; struct mhi_chan *ul_chan = mhi_dev->ul_chan; struct mhi_chan *dl_chan = mhi_dev->dl_chan; + int ret; + + /* Bring device out of LPM */ + ret = mhi_device_get_sync(mhi_dev); + if (ret) + return ret; + + ret = -EINVAL; if (ul_chan) { /* @@ -981,13 +1096,18 @@ static int mhi_driver_probe(struct device *dev) * be provided */ if (ul_chan->lpm_notify && !mhi_drv->status_cb) - return -EINVAL; + goto exit_probe; /* For non-offload channels then xfer_cb should be provided */ if (!ul_chan->offload_ch && !mhi_drv->ul_xfer_cb) - return -EINVAL; + goto exit_probe; ul_chan->xfer_cb = mhi_drv->ul_xfer_cb; + if (ul_chan->auto_start) { + ret = mhi_prepare_channel(mhi_cntrl, ul_chan); + if (ret) + goto exit_probe; + } } if (dl_chan) { @@ -996,11 +1116,11 @@ static int mhi_driver_probe(struct device *dev) * be provided */ if (dl_chan->lpm_notify && !mhi_drv->status_cb) - return -EINVAL; + goto exit_probe; /* For non-offload channels then xfer_cb should be provided */ if (!dl_chan->offload_ch && !mhi_drv->dl_xfer_cb) - return -EINVAL; + goto exit_probe; mhi_event = &mhi_cntrl->mhi_event[dl_chan->er_index]; @@ -1010,19 +1130,36 @@ static int mhi_driver_probe(struct device *dev) * notify pending data */ if (mhi_event->cl_manage && !mhi_drv->status_cb) - return -EINVAL; + goto exit_probe; dl_chan->xfer_cb = mhi_drv->dl_xfer_cb; } /* Call the user provided probe function */ - return mhi_drv->probe(mhi_dev, mhi_dev->id); + ret = mhi_drv->probe(mhi_dev, mhi_dev->id); + if (ret) + goto exit_probe; + + if (dl_chan && dl_chan->auto_start) + mhi_prepare_channel(mhi_cntrl, dl_chan); + + mhi_device_put(mhi_dev); + + return ret; + +exit_probe: + mhi_unprepare_from_transfer(mhi_dev); + + mhi_device_put(mhi_dev); + + return ret; } static int mhi_driver_remove(struct device *dev) { struct mhi_device *mhi_dev = to_mhi_device(dev); struct mhi_driver *mhi_drv = to_mhi_driver(dev->driver); + struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl; struct mhi_chan *mhi_chan; enum mhi_ch_state ch_state[] = { MHI_CH_STATE_DISABLED, @@ -1054,6 +1191,10 @@ static int mhi_driver_remove(struct device *dev) mhi_chan->ch_state = MHI_CH_STATE_SUSPENDED; write_unlock_irq(&mhi_chan->lock); + /* Reset the non-offload channel */ + if (!mhi_chan->offload_ch) + mhi_reset_chan(mhi_cntrl, mhi_chan); + mutex_unlock(&mhi_chan->mutex); } @@ -1068,11 +1209,20 @@ static int mhi_driver_remove(struct device *dev) mutex_lock(&mhi_chan->mutex); + if (ch_state[dir] == MHI_CH_STATE_ENABLED && + !mhi_chan->offload_ch) + mhi_deinit_chan_ctxt(mhi_cntrl, mhi_chan); + mhi_chan->ch_state = MHI_CH_STATE_DISABLED; mutex_unlock(&mhi_chan->mutex); } + read_lock_bh(&mhi_cntrl->pm_lock); + while (mhi_dev->dev_wake) + mhi_device_put(mhi_dev); + read_unlock_bh(&mhi_cntrl->pm_lock); + return 0; } diff --git a/drivers/bus/mhi/core/internal.h b/drivers/bus/mhi/core/internal.h index aa8a3433afae..0b95a1ab6dfd 100644 --- a/drivers/bus/mhi/core/internal.h +++ b/drivers/bus/mhi/core/internal.h @@ -599,6 +599,8 @@ int mhi_pm_m0_transition(struct mhi_controller *mhi_cntrl); void mhi_pm_m1_transition(struct mhi_controller *mhi_cntrl); int mhi_pm_m3_transition(struct mhi_controller *mhi_cntrl); int __mhi_device_get_sync(struct mhi_controller *mhi_cntrl); +int mhi_send_cmd(struct mhi_controller *mhi_cntrl, struct mhi_chan *mhi_chan, + enum mhi_cmd_type cmd); /* Register access methods */ void mhi_db_brstmode(struct mhi_controller *mhi_cntrl, struct db_cfg *db_cfg, @@ -630,6 +632,14 @@ int mhi_init_irq_setup(struct mhi_controller *mhi_cntrl); void mhi_deinit_free_irq(struct mhi_controller *mhi_cntrl); void mhi_rddm_prepare(struct mhi_controller *mhi_cntrl, struct image_info *img_info); +int mhi_prepare_channel(struct mhi_controller *mhi_cntrl, + struct mhi_chan *mhi_chan); +int mhi_init_chan_ctxt(struct mhi_controller *mhi_cntrl, + struct mhi_chan *mhi_chan); +void mhi_deinit_chan_ctxt(struct mhi_controller *mhi_cntrl, + struct mhi_chan *mhi_chan); +void mhi_reset_chan(struct mhi_controller *mhi_cntrl, + struct mhi_chan *mhi_chan); /* Memory allocation methods */ static inline void *mhi_alloc_coherent(struct mhi_controller *mhi_cntrl, @@ -663,4 +673,27 @@ irqreturn_t mhi_irq_handler(int irq_number, void *dev); irqreturn_t mhi_intvec_threaded_handler(int irq_number, void *dev); irqreturn_t mhi_intvec_handler(int irq_number, void *dev); +/* Queue transfer methods */ +int mhi_queue_dma(struct mhi_device *mhi_dev, struct mhi_chan *mhi_chan, + void *buf, size_t len, enum mhi_flags mflags); +int mhi_gen_tre(struct mhi_controller *mhi_cntrl, struct mhi_chan *mhi_chan, + void *buf, void *cb, size_t buf_len, enum mhi_flags flags); +int mhi_queue_buf(struct mhi_device *mhi_dev, struct mhi_chan *mhi_chan, + void *buf, size_t len, enum mhi_flags mflags); +int mhi_queue_skb(struct mhi_device *mhi_dev, struct mhi_chan *mhi_chan, + void *buf, size_t len, enum mhi_flags mflags); +int mhi_queue_sclist(struct mhi_device *mhi_dev, struct mhi_chan *mhi_chan, + void *buf, size_t len, enum mhi_flags mflags); +int mhi_queue_nop(struct mhi_device *mhi_dev, struct mhi_chan *mhi_chan, + void *buf, size_t len, enum mhi_flags mflags); + +int mhi_map_single_no_bb(struct mhi_controller *mhi_cntrl, + struct mhi_buf_info *buf_info); +int mhi_map_single_use_bb(struct mhi_controller *mhi_cntrl, + struct mhi_buf_info *buf_info); +void mhi_unmap_single_no_bb(struct mhi_controller *mhi_cntrl, + struct mhi_buf_info *buf_info); +void mhi_unmap_single_use_bb(struct mhi_controller *mhi_cntrl, + struct mhi_buf_info *buf_info); + #endif /* _MHI_INT_H */ diff --git a/drivers/bus/mhi/core/main.c b/drivers/bus/mhi/core/main.c index 775d4a8fdefd..9891a5c0ce2c 100644 --- a/drivers/bus/mhi/core/main.c +++ b/drivers/bus/mhi/core/main.c @@ -144,11 +144,82 @@ enum mhi_state mhi_get_mhi_state(struct mhi_controller *mhi_cntrl) return ret ? MHI_STATE_MAX : state; } +int mhi_map_single_no_bb(struct mhi_controller *mhi_cntrl, + struct mhi_buf_info *buf_info) +{ + buf_info->p_addr = dma_map_single(mhi_cntrl->dev, buf_info->v_addr, + buf_info->len, buf_info->dir); + if (dma_mapping_error(mhi_cntrl->dev, buf_info->p_addr)) + return -ENOMEM; + + return 0; +} + +int mhi_map_single_use_bb(struct mhi_controller *mhi_cntrl, + struct mhi_buf_info *buf_info) +{ + void *buf = mhi_alloc_coherent(mhi_cntrl, buf_info->len, + &buf_info->p_addr, GFP_ATOMIC); + + if (!buf) + return -ENOMEM; + + if (buf_info->dir == DMA_TO_DEVICE) + memcpy(buf, buf_info->v_addr, buf_info->len); + + buf_info->bb_addr = buf; + + return 0; +} + +void mhi_unmap_single_no_bb(struct mhi_controller *mhi_cntrl, + struct mhi_buf_info *buf_info) +{ + dma_unmap_single(mhi_cntrl->dev, buf_info->p_addr, buf_info->len, + buf_info->dir); +} + +void mhi_unmap_single_use_bb(struct mhi_controller *mhi_cntrl, + struct mhi_buf_info *buf_info) +{ + if (buf_info->dir == DMA_FROM_DEVICE) + memcpy(buf_info->v_addr, buf_info->bb_addr, buf_info->len); + + mhi_free_coherent(mhi_cntrl, buf_info->len, buf_info->bb_addr, + buf_info->p_addr); +} + +static int get_nr_avail_ring_elements(struct mhi_controller *mhi_cntrl, + struct mhi_ring *ring) +{ + int nr_el; + + if (ring->wp < ring->rp) { + nr_el = ((ring->rp - ring->wp) / ring->el_size) - 1; + } else { + nr_el = (ring->rp - ring->base) / ring->el_size; + nr_el += ((ring->base + ring->len - ring->wp) / + ring->el_size) - 1; + } + + return nr_el; +} + static void *mhi_to_virtual(struct mhi_ring *ring, dma_addr_t addr) { return (addr - ring->iommu_base) + ring->base; } +static void mhi_add_ring_element(struct mhi_controller *mhi_cntrl, + struct mhi_ring *ring) +{ + ring->wp += ring->el_size; + if (ring->wp >= (ring->base + ring->len)) + ring->wp = ring->base; + /* smp update */ + smp_wmb(); +} + static void mhi_del_ring_element(struct mhi_controller *mhi_cntrl, struct mhi_ring *ring) { @@ -415,23 +486,25 @@ static int parse_xfer_event(struct mhi_controller *mhi_cntrl, /* Get the TRB this event points to */ ev_tre = mhi_to_virtual(tre_ring, ptr); - /* device rp after servicing the TREs */ dev_rp = ev_tre + 1; if (dev_rp >= (tre_ring->base + tre_ring->len)) dev_rp = tre_ring->base; result.dir = mhi_chan->dir; - /* local rp */ local_rp = tre_ring->rp; while (local_rp != dev_rp) { buf_info = buf_ring->rp; - /* if it's last tre get len from the event */ + /* If it's the last TRE, get length from the event */ if (local_rp == ev_tre) xfer_len = MHI_TRE_GET_EV_LEN(event); else xfer_len = buf_info->len; + /* Unmap if it's not pre-mapped by client */ + if (likely(!buf_info->pre_mapped)) + mhi_cntrl->unmap_single(mhi_cntrl, buf_info); + result.buf_addr = buf_info->cb_buf; result.bytes_xferd = xfer_len; mhi_del_ring_element(mhi_cntrl, buf_ring); @@ -443,6 +516,22 @@ static int parse_xfer_event(struct mhi_controller *mhi_cntrl, if (mhi_chan->dir == DMA_TO_DEVICE) atomic_dec(&mhi_cntrl->pending_pkts); + + /* + * Recycle the buffer if buffer is pre-allocated, + * if there is an error, not much we can do apart + * from dropping the packet + */ + if (mhi_chan->pre_alloc) { + if (mhi_queue_buf(mhi_chan->mhi_dev, mhi_chan, + buf_info->cb_buf, + buf_info->len, MHI_EOT)) { + dev_err(mhi_cntrl->dev, + "Error recycling buffer for chan:%d\n", + mhi_chan->chan); + kfree(buf_info->cb_buf); + } + } } break; } /* CC_EOT */ @@ -803,3 +892,685 @@ void mhi_ctrl_ev_task(unsigned long data) schedule_work(&mhi_cntrl->syserr_worker); } } + +static bool mhi_is_ring_full(struct mhi_controller *mhi_cntrl, + struct mhi_ring *ring) +{ + void *tmp = ring->wp + ring->el_size; + + if (tmp >= (ring->base + ring->len)) + tmp = ring->base; + + return (tmp == ring->rp); +} + +/* TODO: Scatter-Gather transfer not implemented */ +int mhi_queue_sclist(struct mhi_device *mhi_dev, struct mhi_chan *mhi_chan, + void *buf, size_t len, enum mhi_flags mflags) +{ + return -EINVAL; +} + +/* + * MHI client drivers are not allowed to queue buffer for pre allocated + * channels. Hence, this function just returns -EINVAL. + */ +int mhi_queue_nop(struct mhi_device *mhi_dev, struct mhi_chan *mhi_chan, + void *buf, size_t len, enum mhi_flags mflags) +{ + return -EINVAL; +} + +int mhi_queue_skb(struct mhi_device *mhi_dev, struct mhi_chan *mhi_chan, + void *buf, size_t len, enum mhi_flags mflags) +{ + struct sk_buff *skb = buf; + struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl; + struct mhi_ring *tre_ring = &mhi_chan->tre_ring; + struct mhi_ring *buf_ring = &mhi_chan->buf_ring; + struct mhi_buf_info *buf_info; + struct mhi_tre *mhi_tre; + int ret; + + if (mhi_is_ring_full(mhi_cntrl, tre_ring)) + return -ENOMEM; + + read_lock_bh(&mhi_cntrl->pm_lock); + if (unlikely(MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state))) { + read_unlock_bh(&mhi_cntrl->pm_lock); + return -EIO; + } + + /* we're in M3 or transitioning to M3 */ + if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state)) { + mhi_cntrl->runtime_get(mhi_cntrl); + mhi_cntrl->runtime_put(mhi_cntrl); + } + + /* Toggle wake to exit out of M2 */ + mhi_cntrl->wake_toggle(mhi_cntrl); + + /* Generate the TRE */ + buf_info = buf_ring->wp; + + buf_info->v_addr = skb->data; + buf_info->cb_buf = skb; + buf_info->wp = tre_ring->wp; + buf_info->dir = mhi_chan->dir; + buf_info->len = len; + ret = mhi_cntrl->map_single(mhi_cntrl, buf_info); + if (ret) + goto map_error; + + mhi_tre = tre_ring->wp; + + mhi_tre->ptr = MHI_TRE_DATA_PTR(buf_info->p_addr); + mhi_tre->dword[0] = MHI_TRE_DATA_DWORD0(buf_info->len); + mhi_tre->dword[1] = MHI_TRE_DATA_DWORD1(1, 1, 0, 0); + + /* increment WP */ + mhi_add_ring_element(mhi_cntrl, tre_ring); + mhi_add_ring_element(mhi_cntrl, buf_ring); + + if (mhi_chan->dir == DMA_TO_DEVICE) + atomic_inc(&mhi_cntrl->pending_pkts); + + if (likely(MHI_DB_ACCESS_VALID(mhi_cntrl))) { + read_lock_bh(&mhi_chan->lock); + mhi_ring_chan_db(mhi_cntrl, mhi_chan); + read_unlock_bh(&mhi_chan->lock); + } + + read_unlock_bh(&mhi_cntrl->pm_lock); + + return 0; + +map_error: + read_unlock_bh(&mhi_cntrl->pm_lock); + + return ret; +} + +int mhi_queue_dma(struct mhi_device *mhi_dev, + struct mhi_chan *mhi_chan, + void *buf, + size_t len, + enum mhi_flags mflags) +{ + struct mhi_buf *mhi_buf = buf; + struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl; + struct mhi_ring *tre_ring = &mhi_chan->tre_ring; + struct mhi_ring *buf_ring = &mhi_chan->buf_ring; + struct mhi_buf_info *buf_info; + struct mhi_tre *mhi_tre; + + if (mhi_is_ring_full(mhi_cntrl, tre_ring)) + return -ENOMEM; + + read_lock_bh(&mhi_cntrl->pm_lock); + if (unlikely(MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state))) { + dev_err(mhi_cntrl->dev, + "MHI is not in activate state, PM state: %s\n", + to_mhi_pm_state_str(mhi_cntrl->pm_state)); + read_unlock_bh(&mhi_cntrl->pm_lock); + + return -EIO; + } + + /* we're in M3 or transitioning to M3 */ + if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state)) { + mhi_cntrl->runtime_get(mhi_cntrl); + mhi_cntrl->runtime_put(mhi_cntrl); + } + + /* Toggle wake to exit out of M2 */ + mhi_cntrl->wake_toggle(mhi_cntrl); + + /* Generate the TRE */ + buf_info = buf_ring->wp; + WARN_ON(buf_info->used); + buf_info->p_addr = mhi_buf->dma_addr; + buf_info->pre_mapped = true; + buf_info->cb_buf = mhi_buf; + buf_info->wp = tre_ring->wp; + buf_info->dir = mhi_chan->dir; + buf_info->len = len; + + mhi_tre = tre_ring->wp; + + if (mhi_chan->xfer_type == MHI_BUF_RSC_DMA) { + buf_info->used = true; + mhi_tre->ptr = + MHI_RSCTRE_DATA_PTR(buf_info->p_addr, buf_info->len); + mhi_tre->dword[0] = + MHI_RSCTRE_DATA_DWORD0(buf_ring->wp - buf_ring->base); + mhi_tre->dword[1] = MHI_RSCTRE_DATA_DWORD1; + } else { + mhi_tre->ptr = MHI_TRE_DATA_PTR(buf_info->p_addr); + mhi_tre->dword[0] = MHI_TRE_DATA_DWORD0(buf_info->len); + mhi_tre->dword[1] = MHI_TRE_DATA_DWORD1(1, 1, 0, 0); + } + + /* increment WP */ + mhi_add_ring_element(mhi_cntrl, tre_ring); + mhi_add_ring_element(mhi_cntrl, buf_ring); + + if (mhi_chan->dir == DMA_TO_DEVICE) + atomic_inc(&mhi_cntrl->pending_pkts); + + if (likely(MHI_DB_ACCESS_VALID(mhi_cntrl))) { + read_lock_bh(&mhi_chan->lock); + mhi_ring_chan_db(mhi_cntrl, mhi_chan); + read_unlock_bh(&mhi_chan->lock); + } + + read_unlock_bh(&mhi_cntrl->pm_lock); + + return 0; +} + +int mhi_gen_tre(struct mhi_controller *mhi_cntrl, struct mhi_chan *mhi_chan, + void *buf, void *cb, size_t buf_len, enum mhi_flags flags) +{ + struct mhi_ring *buf_ring, *tre_ring; + struct mhi_tre *mhi_tre; + struct mhi_buf_info *buf_info; + int eot, eob, chain, bei; + int ret; + + buf_ring = &mhi_chan->buf_ring; + tre_ring = &mhi_chan->tre_ring; + + buf_info = buf_ring->wp; + buf_info->v_addr = buf; + buf_info->cb_buf = cb; + buf_info->wp = tre_ring->wp; + buf_info->dir = mhi_chan->dir; + buf_info->len = buf_len; + + ret = mhi_cntrl->map_single(mhi_cntrl, buf_info); + if (ret) + return ret; + + eob = !!(flags & MHI_EOB); + eot = !!(flags & MHI_EOT); + chain = !!(flags & MHI_CHAIN); + bei = !!(mhi_chan->intmod); + + mhi_tre = tre_ring->wp; + mhi_tre->ptr = MHI_TRE_DATA_PTR(buf_info->p_addr); + mhi_tre->dword[0] = MHI_TRE_DATA_DWORD0(buf_len); + mhi_tre->dword[1] = MHI_TRE_DATA_DWORD1(bei, eot, eob, chain); + + /* increment WP */ + mhi_add_ring_element(mhi_cntrl, tre_ring); + mhi_add_ring_element(mhi_cntrl, buf_ring); + + return 0; +} + +int mhi_queue_transfer(struct mhi_device *mhi_dev, + enum dma_data_direction dir, void *buf, size_t len, + enum mhi_flags mflags) +{ + if (dir == DMA_TO_DEVICE) + return mhi_dev->ul_chan->queue_xfer(mhi_dev, mhi_dev->ul_chan, + buf, len, mflags); + else + return mhi_dev->dl_chan->queue_xfer(mhi_dev, mhi_dev->dl_chan, + buf, len, mflags); +} +EXPORT_SYMBOL_GPL(mhi_queue_transfer); + +int mhi_queue_buf(struct mhi_device *mhi_dev, struct mhi_chan *mhi_chan, + void *buf, size_t len, enum mhi_flags mflags) +{ + struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl; + struct mhi_ring *tre_ring; + unsigned long flags; + int ret; + + /* + * this check here only as a guard, it's always + * possible mhi can enter error while executing rest of function, + * which is not fatal so we do not need to hold pm_lock + */ + if (unlikely(MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state))) + return -EIO; + + tre_ring = &mhi_chan->tre_ring; + if (mhi_is_ring_full(mhi_cntrl, tre_ring)) + return -ENOMEM; + + ret = mhi_chan->gen_tre(mhi_cntrl, mhi_chan, buf, buf, len, mflags); + if (unlikely(ret)) + return ret; + + read_lock_irqsave(&mhi_cntrl->pm_lock, flags); + + /* we're in M3 or transitioning to M3 */ + if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state)) { + mhi_cntrl->runtime_get(mhi_cntrl); + mhi_cntrl->runtime_put(mhi_cntrl); + } + + /* Toggle wake to exit out of M2 */ + mhi_cntrl->wake_toggle(mhi_cntrl); + + if (mhi_chan->dir == DMA_TO_DEVICE) + atomic_inc(&mhi_cntrl->pending_pkts); + + if (likely(MHI_DB_ACCESS_VALID(mhi_cntrl))) { + unsigned long flags; + + read_lock_irqsave(&mhi_chan->lock, flags); + mhi_ring_chan_db(mhi_cntrl, mhi_chan); + read_unlock_irqrestore(&mhi_chan->lock, flags); + } + + read_unlock_irqrestore(&mhi_cntrl->pm_lock, flags); + + return 0; +} + +int mhi_send_cmd(struct mhi_controller *mhi_cntrl, + struct mhi_chan *mhi_chan, + enum mhi_cmd_type cmd) +{ + struct mhi_tre *cmd_tre = NULL; + struct mhi_cmd *mhi_cmd = &mhi_cntrl->mhi_cmd[PRIMARY_CMD_RING]; + struct mhi_ring *ring = &mhi_cmd->ring; + int chan = 0; + + if (mhi_chan) + chan = mhi_chan->chan; + + spin_lock_bh(&mhi_cmd->lock); + if (!get_nr_avail_ring_elements(mhi_cntrl, ring)) { + spin_unlock_bh(&mhi_cmd->lock); + return -ENOMEM; + } + + /* prepare the cmd tre */ + cmd_tre = ring->wp; + switch (cmd) { + case MHI_CMD_RESET_CHAN: + cmd_tre->ptr = MHI_TRE_CMD_RESET_PTR; + cmd_tre->dword[0] = MHI_TRE_CMD_RESET_DWORD0; + cmd_tre->dword[1] = MHI_TRE_CMD_RESET_DWORD1(chan); + break; + case MHI_CMD_START_CHAN: + cmd_tre->ptr = MHI_TRE_CMD_START_PTR; + cmd_tre->dword[0] = MHI_TRE_CMD_START_DWORD0; + cmd_tre->dword[1] = MHI_TRE_CMD_START_DWORD1(chan); + break; + default: + dev_err(mhi_cntrl->dev, "Command not supported\n"); + break; + } + + /* queue to hardware */ + mhi_add_ring_element(mhi_cntrl, ring); + read_lock_bh(&mhi_cntrl->pm_lock); + if (likely(MHI_DB_ACCESS_VALID(mhi_cntrl))) + mhi_ring_cmd_db(mhi_cntrl, mhi_cmd); + read_unlock_bh(&mhi_cntrl->pm_lock); + spin_unlock_bh(&mhi_cmd->lock); + + return 0; +} + +static void __mhi_unprepare_channel(struct mhi_controller *mhi_cntrl, + struct mhi_chan *mhi_chan) +{ + int ret; + + dev_dbg(mhi_cntrl->dev, "Entered: unprepare channel:%d\n", + mhi_chan->chan); + + /* no more processing events for this channel */ + mutex_lock(&mhi_chan->mutex); + write_lock_irq(&mhi_chan->lock); + if (mhi_chan->ch_state != MHI_CH_STATE_ENABLED) { + write_unlock_irq(&mhi_chan->lock); + mutex_unlock(&mhi_chan->mutex); + return; + } + + mhi_chan->ch_state = MHI_CH_STATE_DISABLED; + write_unlock_irq(&mhi_chan->lock); + + reinit_completion(&mhi_chan->completion); + read_lock_bh(&mhi_cntrl->pm_lock); + if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) { + read_unlock_bh(&mhi_cntrl->pm_lock); + goto error_invalid_state; + } + + mhi_cntrl->wake_toggle(mhi_cntrl); + read_unlock_bh(&mhi_cntrl->pm_lock); + + mhi_cntrl->runtime_get(mhi_cntrl); + mhi_cntrl->runtime_put(mhi_cntrl); + ret = mhi_send_cmd(mhi_cntrl, mhi_chan, MHI_CMD_RESET_CHAN); + if (ret) + goto error_invalid_state; + + /* even if it fails we will still reset */ + ret = wait_for_completion_timeout(&mhi_chan->completion, + msecs_to_jiffies(mhi_cntrl->timeout_ms)); + if (!ret || mhi_chan->ccs != MHI_EV_CC_SUCCESS) + dev_err(mhi_cntrl->dev, + "Failed to receive cmd completion, still resetting\n"); + +error_invalid_state: + if (!mhi_chan->offload_ch) { + mhi_reset_chan(mhi_cntrl, mhi_chan); + mhi_deinit_chan_ctxt(mhi_cntrl, mhi_chan); + } + dev_dbg(mhi_cntrl->dev, "chan:%d successfully resetted\n", + mhi_chan->chan); + mutex_unlock(&mhi_chan->mutex); +} + +int mhi_prepare_channel(struct mhi_controller *mhi_cntrl, + struct mhi_chan *mhi_chan) +{ + int ret = 0; + + dev_dbg(mhi_cntrl->dev, "Preparing channel: %d\n", + mhi_chan->chan); + + if (!(BIT(mhi_cntrl->ee) & mhi_chan->ee_mask)) { + dev_err(mhi_cntrl->dev, + "Current EE: %s Required EE Mask: 0x%x for chan: %s\n", + TO_MHI_EXEC_STR(mhi_cntrl->ee), mhi_chan->ee_mask, + mhi_chan->name); + return -ENOTCONN; + } + + mutex_lock(&mhi_chan->mutex); + + /* If channel is not in disable state, do not allow it to start */ + if (mhi_chan->ch_state != MHI_CH_STATE_DISABLED) { + ret = -EIO; + dev_dbg(mhi_cntrl->dev, + "channel: %d is not in disabled state\n", + mhi_chan->chan); + goto error_init_chan; + } + + /* Check of client manages channel context for offload channels */ + if (!mhi_chan->offload_ch) { + ret = mhi_init_chan_ctxt(mhi_cntrl, mhi_chan); + if (ret) + goto error_init_chan; + } + + reinit_completion(&mhi_chan->completion); + read_lock_bh(&mhi_cntrl->pm_lock); + if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) { + read_unlock_bh(&mhi_cntrl->pm_lock); + ret = -EIO; + goto error_pm_state; + } + + mhi_cntrl->wake_toggle(mhi_cntrl); + read_unlock_bh(&mhi_cntrl->pm_lock); + mhi_cntrl->runtime_get(mhi_cntrl); + mhi_cntrl->runtime_put(mhi_cntrl); + + ret = mhi_send_cmd(mhi_cntrl, mhi_chan, MHI_CMD_START_CHAN); + if (ret) + goto error_pm_state; + + ret = wait_for_completion_timeout(&mhi_chan->completion, + msecs_to_jiffies(mhi_cntrl->timeout_ms)); + if (!ret || mhi_chan->ccs != MHI_EV_CC_SUCCESS) { + ret = -EIO; + goto error_pm_state; + } + + write_lock_irq(&mhi_chan->lock); + mhi_chan->ch_state = MHI_CH_STATE_ENABLED; + write_unlock_irq(&mhi_chan->lock); + + /* Pre-allocate buffer for xfer ring */ + if (mhi_chan->pre_alloc) { + int nr_el = get_nr_avail_ring_elements(mhi_cntrl, + &mhi_chan->tre_ring); + size_t len = mhi_cntrl->buffer_len; + + while (nr_el--) { + void *buf; + + buf = kmalloc(len, GFP_KERNEL); + if (!buf) { + ret = -ENOMEM; + goto error_pre_alloc; + } + + /* Prepare transfer descriptors */ + ret = mhi_chan->gen_tre(mhi_cntrl, mhi_chan, buf, buf, + len, MHI_EOT); + if (ret) { + kfree(buf); + goto error_pre_alloc; + } + } + + read_lock_bh(&mhi_cntrl->pm_lock); + if (MHI_DB_ACCESS_VALID(mhi_cntrl)) { + read_lock_irq(&mhi_chan->lock); + mhi_ring_chan_db(mhi_cntrl, mhi_chan); + read_unlock_irq(&mhi_chan->lock); + } + read_unlock_bh(&mhi_cntrl->pm_lock); + } + + mutex_unlock(&mhi_chan->mutex); + + dev_dbg(mhi_cntrl->dev, "Chan: %d successfully moved to start state\n", + mhi_chan->chan); + + return 0; + +error_pm_state: + if (!mhi_chan->offload_ch) + mhi_deinit_chan_ctxt(mhi_cntrl, mhi_chan); + +error_init_chan: + mutex_unlock(&mhi_chan->mutex); + + return ret; + +error_pre_alloc: + mutex_unlock(&mhi_chan->mutex); + __mhi_unprepare_channel(mhi_cntrl, mhi_chan); + + return ret; +} + +static void mhi_mark_stale_events(struct mhi_controller *mhi_cntrl, + struct mhi_event *mhi_event, + struct mhi_event_ctxt *er_ctxt, + int chan) + +{ + struct mhi_tre *dev_rp, *local_rp; + struct mhi_ring *ev_ring; + unsigned long flags; + + dev_dbg(mhi_cntrl->dev, + "Marking all events for chan: %d as stale\n", chan); + + ev_ring = &mhi_event->ring; + + /* mark all stale events related to channel as STALE event */ + spin_lock_irqsave(&mhi_event->lock, flags); + dev_rp = mhi_to_virtual(ev_ring, er_ctxt->rp); + + local_rp = ev_ring->rp; + while (dev_rp != local_rp) { + if (MHI_TRE_GET_EV_TYPE(local_rp) == + MHI_PKT_TYPE_TX_EVENT && + chan == MHI_TRE_GET_EV_CHID(local_rp)) + local_rp->dword[1] = MHI_TRE_EV_DWORD1(chan, + MHI_PKT_TYPE_STALE_EVENT); + local_rp++; + if (local_rp == (ev_ring->base + ev_ring->len)) + local_rp = ev_ring->base; + } + + + dev_dbg(mhi_cntrl->dev, + "Finished marking events as stale events\n"); + spin_unlock_irqrestore(&mhi_event->lock, flags); +} + +static void mhi_reset_data_chan(struct mhi_controller *mhi_cntrl, + struct mhi_chan *mhi_chan) +{ + struct mhi_ring *buf_ring, *tre_ring; + struct mhi_result result; + + /* Reset any pending buffers */ + buf_ring = &mhi_chan->buf_ring; + tre_ring = &mhi_chan->tre_ring; + result.transaction_status = -ENOTCONN; + result.bytes_xferd = 0; + while (tre_ring->rp != tre_ring->wp) { + struct mhi_buf_info *buf_info = buf_ring->rp; + + if (mhi_chan->dir == DMA_TO_DEVICE) + atomic_dec(&mhi_cntrl->pending_pkts); + + if (!buf_info->pre_mapped) + mhi_cntrl->unmap_single(mhi_cntrl, buf_info); + + mhi_del_ring_element(mhi_cntrl, buf_ring); + mhi_del_ring_element(mhi_cntrl, tre_ring); + + if (mhi_chan->pre_alloc) { + kfree(buf_info->cb_buf); + } else { + result.buf_addr = buf_info->cb_buf; + mhi_chan->xfer_cb(mhi_chan->mhi_dev, &result); + } + } +} + +static void mhi_reset_rsc_chan(struct mhi_controller *mhi_cntrl, + struct mhi_chan *mhi_chan) +{ + struct mhi_ring *buf_ring, *tre_ring; + struct mhi_result result; + struct mhi_buf_info *buf_info; + + /* Reset any pending buffers */ + buf_ring = &mhi_chan->buf_ring; + tre_ring = &mhi_chan->tre_ring; + result.transaction_status = -ENOTCONN; + result.bytes_xferd = 0; + + buf_info = buf_ring->base; + for (; (void *)buf_info < buf_ring->base + buf_ring->len; buf_info++) { + if (!buf_info->used) + continue; + + result.buf_addr = buf_info->cb_buf; + mhi_chan->xfer_cb(mhi_chan->mhi_dev, &result); + buf_info->used = false; + } +} + +void mhi_reset_chan(struct mhi_controller *mhi_cntrl, struct mhi_chan *mhi_chan) +{ + + struct mhi_event *mhi_event; + struct mhi_event_ctxt *er_ctxt; + int chan = mhi_chan->chan; + + /* Nothing to reset, client doesn't queue buffers */ + if (mhi_chan->offload_ch) + return; + + read_lock_bh(&mhi_cntrl->pm_lock); + mhi_event = &mhi_cntrl->mhi_event[mhi_chan->er_index]; + er_ctxt = &mhi_cntrl->mhi_ctxt->er_ctxt[mhi_chan->er_index]; + + mhi_mark_stale_events(mhi_cntrl, mhi_event, er_ctxt, chan); + + if (mhi_chan->xfer_type == MHI_BUF_RSC_DMA) + mhi_reset_rsc_chan(mhi_cntrl, mhi_chan); + else + mhi_reset_data_chan(mhi_cntrl, mhi_chan); + + read_unlock_bh(&mhi_cntrl->pm_lock); +} + +/* Move channel to start state */ +int mhi_prepare_for_transfer(struct mhi_device *mhi_dev) +{ + int ret, dir; + struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl; + struct mhi_chan *mhi_chan; + + for (dir = 0; dir < 2; dir++) { + mhi_chan = dir ? mhi_dev->dl_chan : mhi_dev->ul_chan; + + if (!mhi_chan) + continue; + + ret = mhi_prepare_channel(mhi_cntrl, mhi_chan); + if (ret) + goto error_open_chan; + } + + return 0; + +error_open_chan: + for (--dir; dir >= 0; dir--) { + mhi_chan = dir ? mhi_dev->dl_chan : mhi_dev->ul_chan; + + if (!mhi_chan) + continue; + + __mhi_unprepare_channel(mhi_cntrl, mhi_chan); + } + + return ret; +} +EXPORT_SYMBOL_GPL(mhi_prepare_for_transfer); + +void mhi_unprepare_from_transfer(struct mhi_device *mhi_dev) +{ + struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl; + struct mhi_chan *mhi_chan; + int dir; + + for (dir = 0; dir < 2; dir++) { + mhi_chan = dir ? mhi_dev->ul_chan : mhi_dev->dl_chan; + + if (!mhi_chan) + continue; + + __mhi_unprepare_channel(mhi_cntrl, mhi_chan); + } +} +EXPORT_SYMBOL_GPL(mhi_unprepare_from_transfer); + +int mhi_poll(struct mhi_device *mhi_dev, u32 budget) +{ + struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl; + struct mhi_chan *mhi_chan = mhi_dev->dl_chan; + struct mhi_event *mhi_event = &mhi_cntrl->mhi_event[mhi_chan->er_index]; + int ret; + + spin_lock_bh(&mhi_event->lock); + ret = mhi_event->process_event(mhi_cntrl, mhi_event, budget); + spin_unlock_bh(&mhi_event->lock); + + return ret; +} +EXPORT_SYMBOL_GPL(mhi_poll); diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c index 19987068b475..e37678037cde 100644 --- a/drivers/bus/mhi/core/pm.c +++ b/drivers/bus/mhi/core/pm.c @@ -925,3 +925,43 @@ int mhi_force_rddm_mode(struct mhi_controller *mhi_cntrl) return ret; } EXPORT_SYMBOL_GPL(mhi_force_rddm_mode); + +void mhi_device_get(struct mhi_device *mhi_dev) +{ + struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl; + + mhi_dev->dev_wake++; + read_lock_bh(&mhi_cntrl->pm_lock); + mhi_cntrl->wake_get(mhi_cntrl, true); + read_unlock_bh(&mhi_cntrl->pm_lock); +} +EXPORT_SYMBOL_GPL(mhi_device_get); + +int mhi_device_get_sync(struct mhi_device *mhi_dev) +{ + struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl; + int ret; + + ret = __mhi_device_get_sync(mhi_cntrl); + if (!ret) + mhi_dev->dev_wake++; + + return ret; +} +EXPORT_SYMBOL_GPL(mhi_device_get_sync); + +void mhi_device_put(struct mhi_device *mhi_dev) +{ + struct mhi_controller *mhi_cntrl = mhi_dev->mhi_cntrl; + + mhi_dev->dev_wake--; + read_lock_bh(&mhi_cntrl->pm_lock); + if (MHI_PM_IN_SUSPEND_STATE(mhi_cntrl->pm_state)) { + mhi_cntrl->runtime_get(mhi_cntrl); + mhi_cntrl->runtime_put(mhi_cntrl); + } + + mhi_cntrl->wake_put(mhi_cntrl, false); + read_unlock_bh(&mhi_cntrl->pm_lock); +} +EXPORT_SYMBOL_GPL(mhi_device_put); diff --git a/include/linux/mhi.h b/include/linux/mhi.h index 2ea2deb922a1..a32548ac3425 100644 --- a/include/linux/mhi.h +++ b/include/linux/mhi.h @@ -359,6 +359,8 @@ struct mhi_controller_config { * @wake_toggle: CB function to assert and de-assert device wake (optional) * @runtime_get: CB function to controller runtime resume (required) * @runtimet_put: CB function to decrement pm usage (required) + * @map_single: CB function to create TRE buffer + * @unmap_single: CB function to destroy TRE buffer * @buffer_len: Bounce buffer length * @bounce_buf: Use of bounce buffer * @fbc_download: MHI host needs to do complete image transfer (optional) @@ -421,6 +423,10 @@ struct mhi_controller { void (*wake_toggle)(struct mhi_controller *mhi_cntrl); int (*runtime_get)(struct mhi_controller *mhi_cntrl); void (*runtime_put)(struct mhi_controller *mhi_cntrl); + int (*map_single)(struct mhi_controller *mhi_cntrl, + struct mhi_buf_info *buf); + void (*unmap_single)(struct mhi_controller *mhi_cntrl, + struct mhi_buf_info *buf); size_t buffer_len; bool bounce_buf; @@ -603,4 +609,53 @@ int mhi_force_rddm_mode(struct mhi_controller *mhi_cntrl); */ enum mhi_state mhi_get_mhi_state(struct mhi_controller *mhi_cntrl); +/** + * mhi_device_get - Disable device low power mode + * @mhi_dev: Device associated with the channel + */ +void mhi_device_get(struct mhi_device *mhi_dev); + +/** + * mhi_device_get_sync - Disable device low power mode. Synchronously + * take the controller out of suspended state + * @mhi_dev: Device associated with the channel + */ +int mhi_device_get_sync(struct mhi_device *mhi_dev); + +/** + * mhi_device_put - Re-enable device low power mode + * @mhi_dev: Device associated with the channel + */ +void mhi_device_put(struct mhi_device *mhi_dev); + +/** + * mhi_prepare_for_transfer - Setup channel for data transfer + * @mhi_dev: Device associated with the channels + */ +int mhi_prepare_for_transfer(struct mhi_device *mhi_dev); + +/** + * mhi_unprepare_from_transfer - Unprepare the channels + * @mhi_dev: Device associated with the channels + */ +void mhi_unprepare_from_transfer(struct mhi_device *mhi_dev); + +/** + * mhi_poll - Poll for any available data in DL direction + * @mhi_dev: Device associated with the channels + * @budget: # of events to process + */ +int mhi_poll(struct mhi_device *mhi_dev, u32 budget); + +/** + * mhi_queue_transfer - Send or receive data from client device over MHI channel + * @mhi_dev: Device associated with the channels + * @dir: DMA direction for the channel + * @buf: Buffer for holding the data + * @len: Buffer length + * @mflags: MHI transfer flags used for the transfer + */ +int mhi_queue_transfer(struct mhi_device *mhi_dev, enum dma_data_direction dir, + void *buf, size_t len, enum mhi_flags mflags); + #endif /* _MHI_H_ */ -- 2.17.1
