From b5a8d233a588b3acf2a7a3a8da30f8f68f376626 Mon Sep 17 00:00:00 2001 From: Loic Poulain Date: Mon, 4 Jan 2021 17:14:50 +0100 Subject: bus: mhi: core: Add device hardware reset support The MHI specification allows to perform a hard reset of the device when writing to the SOC_RESET register. It can be used to completely restart the device (e.g. in case of unrecoverable MHI error). This is up to the MHI controller driver to determine when this hard reset should be used, and in case of MHI errors, should be used as a reset of last resort (after standard MHI stack reset). This function is a stateless function, the MHI layer do nothing except triggering the reset by writing into the right register(s), this is up to the caller to ensure right mhi_controller state (e.g. unregister the controller if necessary). Signed-off-by: Loic Poulain Reviewed-by: Manivannan Sadhasivam Signed-off-by: Manivannan Sadhasivam --- include/linux/mhi.h | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'include/linux') diff --git a/include/linux/mhi.h b/include/linux/mhi.h index 562862ff819c..54afcae1709a 100644 --- a/include/linux/mhi.h +++ b/include/linux/mhi.h @@ -347,6 +347,7 @@ struct mhi_controller_config { * @unmap_single: CB function to destroy TRE buffer * @read_reg: Read a MHI register via the physical link (required) * @write_reg: Write a MHI register via the physical link (required) + * @reset: Controller specific reset function (optional) * @buffer_len: Bounce buffer length * @index: Index of the MHI controller instance * @bounce_buf: Use of bounce buffer @@ -437,6 +438,7 @@ struct mhi_controller { u32 *out); void (*write_reg)(struct mhi_controller *mhi_cntrl, void __iomem *addr, u32 val); + void (*reset)(struct mhi_controller *mhi_cntrl); size_t buffer_len; int index; @@ -672,6 +674,13 @@ enum mhi_ee_type mhi_get_exec_env(struct mhi_controller *mhi_cntrl); */ enum mhi_state mhi_get_mhi_state(struct mhi_controller *mhi_cntrl); +/** + * mhi_soc_reset - Trigger a device reset. This can be used as a last resort + * to reset and recover a device. + * @mhi_cntrl: MHI controller + */ +void mhi_soc_reset(struct mhi_controller *mhi_cntrl); + /** * mhi_device_get - Disable device low power mode * @mhi_dev: Device associated with the channel -- cgit v1.2.3 From fcba4b2047a31a55e1cef73849363a3cf7c2736d Mon Sep 17 00:00:00 2001 From: Loic Poulain Date: Tue, 5 Jan 2021 17:44:35 +0100 Subject: mhi: unconstify mhi_event_config Some parameters may have to be determined at runtime. It is the case for the event ring MSI vector. Signed-off-by: Loic Poulain Reviewed-by: Manivannan Sadhasivam Signed-off-by: Manivannan Sadhasivam --- include/linux/mhi.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/mhi.h b/include/linux/mhi.h index 54afcae1709a..48f5c9168ae0 100644 --- a/include/linux/mhi.h +++ b/include/linux/mhi.h @@ -279,7 +279,7 @@ struct mhi_controller_config { u32 num_channels; const struct mhi_channel_config *ch_cfg; u32 num_events; - const struct mhi_event_config *event_cfg; + struct mhi_event_config *event_cfg; bool use_bounce_buf; bool m2_no_db; }; -- cgit v1.2.3 From 6ffcc18d9c0b4522c95aab71ff3ff5a56e699945 Mon Sep 17 00:00:00 2001 From: Carl Huang Date: Mon, 4 Jan 2021 18:11:28 +0800 Subject: mhi: use irq_flags if controller driver configures it If controller driver has specified the irq_flags, mhi uses this specified irq_flags. Otherwise, mhi uses default irq_flags. The purpose of this change is to support one MSI vector for QCA6390. MHI will use one same MSI vector too in this scenario. In case of one MSI vector, IRQ_NO_BALANCING is needed when irq handler is requested. The reason is if irq migration happens, the msi_data may change too. However, the msi_data is already programmed to QCA6390 hardware during initialization phase. This msi_data inconsistence will result in crash in kernel. Another issue is in case of one MSI vector, IRQF_NO_SUSPEND will trigger WARNINGS because QCA6390 wants to disable the IRQ during the suspend. To avoid above two issues, QCA6390 driver specifies the irq_flags in case of one MSI vector when mhi_register_controller is called. Signed-off-by: Carl Huang Reviewed-by: Manivannan Sadhasivam Signed-off-by: Manivannan Sadhasivam --- include/linux/mhi.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux') diff --git a/include/linux/mhi.h b/include/linux/mhi.h index 562862ff819c..b7138127664f 100644 --- a/include/linux/mhi.h +++ b/include/linux/mhi.h @@ -353,6 +353,7 @@ struct mhi_controller_config { * @fbc_download: MHI host needs to do complete image transfer (optional) * @pre_init: MHI host needs to do pre-initialization before power up * @wake_set: Device wakeup set flag + * @irq_flags: irq flags passed to request_irq (optional) * * Fields marked as (required) need to be populated by the controller driver * before calling mhi_register_controller(). For the fields marked as (optional) @@ -444,6 +445,7 @@ struct mhi_controller { bool fbc_download; bool pre_init; bool wake_set; + unsigned long irq_flags; }; /** -- cgit v1.2.3 From 87baa23e0236bc1c41ce744f524bf12dbe7fde66 Mon Sep 17 00:00:00 2001 From: Hemant Kumar Date: Mon, 11 Jan 2021 19:07:40 +0100 Subject: bus: mhi: core: Add helper API to return number of free TREs Introduce mhi_get_free_desc_count() API to return number of TREs available to queue buffer. MHI clients can use this API to know before hand if ring is full without calling queue API. Signed-off-by: Hemant Kumar Reviewed-by: Jeffrey Hugo Reviewed-by: Manivannan Sadhasivam Link: https://lore.kernel.org/r/1610388462-16322-1-git-send-email-loic.poulain@linaro.org Signed-off-by: Manivannan Sadhasivam --- include/linux/mhi.h | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'include/linux') diff --git a/include/linux/mhi.h b/include/linux/mhi.h index 562862ff819c..ece53a252217 100644 --- a/include/linux/mhi.h +++ b/include/linux/mhi.h @@ -598,6 +598,15 @@ void mhi_set_mhi_state(struct mhi_controller *mhi_cntrl, */ void mhi_notify(struct mhi_device *mhi_dev, enum mhi_callback cb_reason); +/** + * mhi_get_free_desc_count - Get transfer ring length + * Get # of TD available to queue buffers + * @mhi_dev: Device associated with the channels + * @dir: Direction of the channel + */ +int mhi_get_free_desc_count(struct mhi_device *mhi_dev, + enum dma_data_direction dir); + /** * mhi_prepare_for_power_up - Do pre-initialization before power up. * This is optional, call this before power up if -- cgit v1.2.3