| Message ID | 20220212182117.49438-21-manivannan.sadhasivam@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | Add initial support for MHI endpoint stack | expand |
On 2/12/22 12:21 PM, Manivannan Sadhasivam wrote: > Add support for processing the command ring. Command ring is used by the > host to issue channel specific commands to the ep device. Following > commands are supported: > > 1. Start channel > 2. Stop channel > 3. Reset channel > > Once the device receives the command doorbell interrupt from host, it > executes the command and generates a command completion event to the > host in the primary event ring. > > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> I'll let you consider my few comments below, but whether or not you address them, this looks OK to me. Reviewed-by: Alex Elder <elder@linaro.org> > --- > drivers/bus/mhi/ep/main.c | 151 ++++++++++++++++++++++++++++++++++++++ > 1 file changed, 151 insertions(+) > > diff --git a/drivers/bus/mhi/ep/main.c b/drivers/bus/mhi/ep/main.c > index 6378ac5c7e37..4c2ee517832c 100644 > --- a/drivers/bus/mhi/ep/main.c > +++ b/drivers/bus/mhi/ep/main.c > @@ -21,6 +21,7 @@ > > static DEFINE_IDA(mhi_ep_cntrl_ida); > > +static int mhi_ep_create_device(struct mhi_ep_cntrl *mhi_cntrl, u32 ch_id); > static int mhi_ep_destroy_device(struct device *dev, void *data); > > static int mhi_ep_send_event(struct mhi_ep_cntrl *mhi_cntrl, u32 ring_idx, > @@ -185,6 +186,156 @@ void mhi_ep_unmap_free(struct mhi_ep_cntrl *mhi_cntrl, u64 pci_addr, phys_addr_t > mhi_cntrl->free_addr(mhi_cntrl, phys - offset, virt - offset, size); > } > > +int mhi_ep_process_cmd_ring(struct mhi_ep_ring *ring, struct mhi_ep_ring_element *el) > +{ > + struct mhi_ep_cntrl *mhi_cntrl = ring->mhi_cntrl; > + struct device *dev = &mhi_cntrl->mhi_dev->dev; > + struct mhi_result result = {}; > + struct mhi_ep_chan *mhi_chan; > + struct mhi_ep_ring *ch_ring; > + u32 tmp, ch_id; > + int ret; > + > + ch_id = MHI_TRE_GET_CMD_CHID(el); > + mhi_chan = &mhi_cntrl->mhi_chan[ch_id]; > + ch_ring = &mhi_cntrl->mhi_chan[ch_id].ring; > + > + switch (MHI_TRE_GET_CMD_TYPE(el)) { No MHI_PKT_TYPE_NOOP_CMD? > + case MHI_PKT_TYPE_START_CHAN_CMD: > + dev_dbg(dev, "Received START command for channel (%d)\n", ch_id); > + > + mutex_lock(&mhi_chan->lock); > + /* Initialize and configure the corresponding channel ring */ > + if (!ch_ring->started) { > + ret = mhi_ep_ring_start(mhi_cntrl, ch_ring, > + (union mhi_ep_ring_ctx *)&mhi_cntrl->ch_ctx_cache[ch_id]); > + if (ret) { > + dev_err(dev, "Failed to start ring for channel (%d)\n", ch_id); > + ret = mhi_ep_send_cmd_comp_event(mhi_cntrl, > + MHI_EV_CC_UNDEFINED_ERR); > + if (ret) > + dev_err(dev, "Error sending completion event (%d)\n", > + MHI_EV_CC_UNDEFINED_ERR); Print the value of ret in the above message (not UNDEFINED_ERR). > + > + goto err_unlock; > + } > + } > + > + /* Enable DB for the channel */ > + mhi_ep_mmio_enable_chdb_a7(mhi_cntrl, ch_id); If an error occurs later, this will be enabled. Is that what you want? Maybe wait to enable the doorbell until everything else succeeds. > + > + /* Set channel state to RUNNING */ > + mhi_chan->state = MHI_CH_STATE_RUNNING; > + tmp = le32_to_cpu(mhi_cntrl->ch_ctx_cache[ch_id].chcfg); > + tmp &= ~CHAN_CTX_CHSTATE_MASK; > + tmp |= FIELD_PREP(CHAN_CTX_CHSTATE_MASK, MHI_CH_STATE_RUNNING); > + mhi_cntrl->ch_ctx_cache[ch_id].chcfg = cpu_to_le32(tmp); > + > + ret = mhi_ep_send_cmd_comp_event(mhi_cntrl, MHI_EV_CC_SUCCESS); > + if (ret) { > + dev_err(dev, "Error sending command completion event (%d)\n", > + MHI_EV_CC_SUCCESS); > + goto err_unlock; > + } > + > + mutex_unlock(&mhi_chan->lock); > + > + /* > + * Create MHI device only during UL channel start. Since the MHI > + * channels operate in a pair, we'll associate both UL and DL > + * channels to the same device. > + * > + * We also need to check for mhi_dev != NULL because, the host > + * will issue START_CHAN command during resume and we don't > + * destroy the device during suspend. > + */ > + if (!(ch_id % 2) && !mhi_chan->mhi_dev) { > + ret = mhi_ep_create_device(mhi_cntrl, ch_id); > + if (ret) { If this occurs, the host will already have been told the request completed successfully. Is that a problem that can/should be avoided? > + dev_err(dev, "Error creating device for channel (%d)\n", ch_id); > + return ret; > + } > + } > + > + break; > + case MHI_PKT_TYPE_STOP_CHAN_CMD: > + dev_dbg(dev, "Received STOP command for channel (%d)\n", ch_id); > + if (!ch_ring->started) { > + dev_err(dev, "Channel (%d) not opened\n", ch_id); > + return -ENODEV; > + } > + > + mutex_lock(&mhi_chan->lock); > + /* Disable DB for the channel */ > + mhi_ep_mmio_disable_chdb_a7(mhi_cntrl, ch_id); > + > + /* Send channel disconnect status to client drivers */ > + result.transaction_status = -ENOTCONN; > + result.bytes_xferd = 0; > + mhi_chan->xfer_cb(mhi_chan->mhi_dev, &result); > + > + /* Set channel state to STOP */ > + mhi_chan->state = MHI_CH_STATE_STOP; > + tmp = le32_to_cpu(mhi_cntrl->ch_ctx_cache[ch_id].chcfg); > + tmp &= ~CHAN_CTX_CHSTATE_MASK; > + tmp |= FIELD_PREP(CHAN_CTX_CHSTATE_MASK, MHI_CH_STATE_STOP); > + mhi_cntrl->ch_ctx_cache[ch_id].chcfg = cpu_to_le32(tmp); > + > + ret = mhi_ep_send_cmd_comp_event(mhi_cntrl, MHI_EV_CC_SUCCESS); > + if (ret) { > + dev_err(dev, "Error sending command completion event (%d)\n", > + MHI_EV_CC_SUCCESS); > + goto err_unlock; > + } > + > + mutex_unlock(&mhi_chan->lock); > + break; > + case MHI_PKT_TYPE_RESET_CHAN_CMD: > + dev_dbg(dev, "Received STOP command for channel (%d)\n", ch_id); > + if (!ch_ring->started) { > + dev_err(dev, "Channel (%d) not opened\n", ch_id); > + return -ENODEV; > + } > + > + mutex_lock(&mhi_chan->lock); > + /* Stop and reset the transfer ring */ > + mhi_ep_ring_reset(mhi_cntrl, ch_ring); > + > + /* Send channel disconnect status to client driver */ > + result.transaction_status = -ENOTCONN; > + result.bytes_xferd = 0; > + mhi_chan->xfer_cb(mhi_chan->mhi_dev, &result); > + > + /* Set channel state to DISABLED */ > + mhi_chan->state = MHI_CH_STATE_DISABLED; > + tmp = le32_to_cpu(mhi_cntrl->ch_ctx_cache[ch_id].chcfg); > + tmp &= ~CHAN_CTX_CHSTATE_MASK; > + tmp |= FIELD_PREP(CHAN_CTX_CHSTATE_MASK, MHI_CH_STATE_DISABLED); > + mhi_cntrl->ch_ctx_cache[ch_id].chcfg = cpu_to_le32(tmp); > + > + ret = mhi_ep_send_cmd_comp_event(mhi_cntrl, MHI_EV_CC_SUCCESS); > + if (ret) { > + dev_err(dev, "Error sending command completion event (%d)\n", > + MHI_EV_CC_SUCCESS); > + goto err_unlock; > + } > + > + mutex_unlock(&mhi_chan->lock); > + break; > + default: > + dev_err(dev, "Invalid command received: %d for channel (%d)\n", > + MHI_TRE_GET_CMD_TYPE(el), ch_id); > + return -EINVAL; > + } > + > + return 0; > + > +err_unlock: > + mutex_unlock(&mhi_chan->lock); > + > + return ret; > +} > + > static int mhi_ep_cache_host_cfg(struct mhi_ep_cntrl *mhi_cntrl) > { > struct device *dev = &mhi_cntrl->mhi_dev->dev;
diff --git a/drivers/bus/mhi/ep/main.c b/drivers/bus/mhi/ep/main.c index 6378ac5c7e37..4c2ee517832c 100644 --- a/drivers/bus/mhi/ep/main.c +++ b/drivers/bus/mhi/ep/main.c @@ -21,6 +21,7 @@ static DEFINE_IDA(mhi_ep_cntrl_ida); +static int mhi_ep_create_device(struct mhi_ep_cntrl *mhi_cntrl, u32 ch_id); static int mhi_ep_destroy_device(struct device *dev, void *data); static int mhi_ep_send_event(struct mhi_ep_cntrl *mhi_cntrl, u32 ring_idx, @@ -185,6 +186,156 @@ void mhi_ep_unmap_free(struct mhi_ep_cntrl *mhi_cntrl, u64 pci_addr, phys_addr_t mhi_cntrl->free_addr(mhi_cntrl, phys - offset, virt - offset, size); } +int mhi_ep_process_cmd_ring(struct mhi_ep_ring *ring, struct mhi_ep_ring_element *el) +{ + struct mhi_ep_cntrl *mhi_cntrl = ring->mhi_cntrl; + struct device *dev = &mhi_cntrl->mhi_dev->dev; + struct mhi_result result = {}; + struct mhi_ep_chan *mhi_chan; + struct mhi_ep_ring *ch_ring; + u32 tmp, ch_id; + int ret; + + ch_id = MHI_TRE_GET_CMD_CHID(el); + mhi_chan = &mhi_cntrl->mhi_chan[ch_id]; + ch_ring = &mhi_cntrl->mhi_chan[ch_id].ring; + + switch (MHI_TRE_GET_CMD_TYPE(el)) { + case MHI_PKT_TYPE_START_CHAN_CMD: + dev_dbg(dev, "Received START command for channel (%d)\n", ch_id); + + mutex_lock(&mhi_chan->lock); + /* Initialize and configure the corresponding channel ring */ + if (!ch_ring->started) { + ret = mhi_ep_ring_start(mhi_cntrl, ch_ring, + (union mhi_ep_ring_ctx *)&mhi_cntrl->ch_ctx_cache[ch_id]); + if (ret) { + dev_err(dev, "Failed to start ring for channel (%d)\n", ch_id); + ret = mhi_ep_send_cmd_comp_event(mhi_cntrl, + MHI_EV_CC_UNDEFINED_ERR); + if (ret) + dev_err(dev, "Error sending completion event (%d)\n", + MHI_EV_CC_UNDEFINED_ERR); + + goto err_unlock; + } + } + + /* Enable DB for the channel */ + mhi_ep_mmio_enable_chdb_a7(mhi_cntrl, ch_id); + + /* Set channel state to RUNNING */ + mhi_chan->state = MHI_CH_STATE_RUNNING; + tmp = le32_to_cpu(mhi_cntrl->ch_ctx_cache[ch_id].chcfg); + tmp &= ~CHAN_CTX_CHSTATE_MASK; + tmp |= FIELD_PREP(CHAN_CTX_CHSTATE_MASK, MHI_CH_STATE_RUNNING); + mhi_cntrl->ch_ctx_cache[ch_id].chcfg = cpu_to_le32(tmp); + + ret = mhi_ep_send_cmd_comp_event(mhi_cntrl, MHI_EV_CC_SUCCESS); + if (ret) { + dev_err(dev, "Error sending command completion event (%d)\n", + MHI_EV_CC_SUCCESS); + goto err_unlock; + } + + mutex_unlock(&mhi_chan->lock); + + /* + * Create MHI device only during UL channel start. Since the MHI + * channels operate in a pair, we'll associate both UL and DL + * channels to the same device. + * + * We also need to check for mhi_dev != NULL because, the host + * will issue START_CHAN command during resume and we don't + * destroy the device during suspend. + */ + if (!(ch_id % 2) && !mhi_chan->mhi_dev) { + ret = mhi_ep_create_device(mhi_cntrl, ch_id); + if (ret) { + dev_err(dev, "Error creating device for channel (%d)\n", ch_id); + return ret; + } + } + + break; + case MHI_PKT_TYPE_STOP_CHAN_CMD: + dev_dbg(dev, "Received STOP command for channel (%d)\n", ch_id); + if (!ch_ring->started) { + dev_err(dev, "Channel (%d) not opened\n", ch_id); + return -ENODEV; + } + + mutex_lock(&mhi_chan->lock); + /* Disable DB for the channel */ + mhi_ep_mmio_disable_chdb_a7(mhi_cntrl, ch_id); + + /* Send channel disconnect status to client drivers */ + result.transaction_status = -ENOTCONN; + result.bytes_xferd = 0; + mhi_chan->xfer_cb(mhi_chan->mhi_dev, &result); + + /* Set channel state to STOP */ + mhi_chan->state = MHI_CH_STATE_STOP; + tmp = le32_to_cpu(mhi_cntrl->ch_ctx_cache[ch_id].chcfg); + tmp &= ~CHAN_CTX_CHSTATE_MASK; + tmp |= FIELD_PREP(CHAN_CTX_CHSTATE_MASK, MHI_CH_STATE_STOP); + mhi_cntrl->ch_ctx_cache[ch_id].chcfg = cpu_to_le32(tmp); + + ret = mhi_ep_send_cmd_comp_event(mhi_cntrl, MHI_EV_CC_SUCCESS); + if (ret) { + dev_err(dev, "Error sending command completion event (%d)\n", + MHI_EV_CC_SUCCESS); + goto err_unlock; + } + + mutex_unlock(&mhi_chan->lock); + break; + case MHI_PKT_TYPE_RESET_CHAN_CMD: + dev_dbg(dev, "Received STOP command for channel (%d)\n", ch_id); + if (!ch_ring->started) { + dev_err(dev, "Channel (%d) not opened\n", ch_id); + return -ENODEV; + } + + mutex_lock(&mhi_chan->lock); + /* Stop and reset the transfer ring */ + mhi_ep_ring_reset(mhi_cntrl, ch_ring); + + /* Send channel disconnect status to client driver */ + result.transaction_status = -ENOTCONN; + result.bytes_xferd = 0; + mhi_chan->xfer_cb(mhi_chan->mhi_dev, &result); + + /* Set channel state to DISABLED */ + mhi_chan->state = MHI_CH_STATE_DISABLED; + tmp = le32_to_cpu(mhi_cntrl->ch_ctx_cache[ch_id].chcfg); + tmp &= ~CHAN_CTX_CHSTATE_MASK; + tmp |= FIELD_PREP(CHAN_CTX_CHSTATE_MASK, MHI_CH_STATE_DISABLED); + mhi_cntrl->ch_ctx_cache[ch_id].chcfg = cpu_to_le32(tmp); + + ret = mhi_ep_send_cmd_comp_event(mhi_cntrl, MHI_EV_CC_SUCCESS); + if (ret) { + dev_err(dev, "Error sending command completion event (%d)\n", + MHI_EV_CC_SUCCESS); + goto err_unlock; + } + + mutex_unlock(&mhi_chan->lock); + break; + default: + dev_err(dev, "Invalid command received: %d for channel (%d)\n", + MHI_TRE_GET_CMD_TYPE(el), ch_id); + return -EINVAL; + } + + return 0; + +err_unlock: + mutex_unlock(&mhi_chan->lock); + + return ret; +} + static int mhi_ep_cache_host_cfg(struct mhi_ep_cntrl *mhi_cntrl) { struct device *dev = &mhi_cntrl->mhi_dev->dev;
Add support for processing the command ring. Command ring is used by the host to issue channel specific commands to the ep device. Following commands are supported: 1. Start channel 2. Stop channel 3. Reset channel Once the device receives the command doorbell interrupt from host, it executes the command and generates a command completion event to the host in the primary event ring. Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> --- drivers/bus/mhi/ep/main.c | 151 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 151 insertions(+)