diff options
| -rw-r--r-- | drivers/firmware/arm_scmi/common.h | 4 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/driver.c | 1 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/mailbox.c | 2 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/optee.c | 2 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/shmem.c | 31 | ||||
| -rw-r--r-- | drivers/firmware/arm_scmi/smc.c | 2 |
6 files changed, 34 insertions, 8 deletions
diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h index 9b87b5b69535..a1c0154c31c6 100644 --- a/drivers/firmware/arm_scmi/common.h +++ b/drivers/firmware/arm_scmi/common.h @@ -118,6 +118,7 @@ void scmi_protocol_release(const struct scmi_handle *handle, u8 protocol_id); * * @dev: Reference to device in the SCMI hierarchy corresponding to this * channel + * @rx_timeout_ms: The configured RX timeout in milliseconds. * @handle: Pointer to SCMI entity handle * @no_completion_irq: Flag to indicate that this channel has no completion * interrupt mechanism for synchronous commands. @@ -127,6 +128,7 @@ void scmi_protocol_release(const struct scmi_handle *handle, u8 protocol_id); */ struct scmi_chan_info { struct device *dev; + unsigned int rx_timeout_ms; struct scmi_handle *handle; bool no_completion_irq; void *transport_info; @@ -233,7 +235,7 @@ void scmi_free_channel(struct scmi_chan_info *cinfo, struct idr *idr, int id); struct scmi_shared_mem; void shmem_tx_prepare(struct scmi_shared_mem __iomem *shmem, - struct scmi_xfer *xfer); + struct scmi_xfer *xfer, struct scmi_chan_info *cinfo); u32 shmem_read_header(struct scmi_shared_mem __iomem *shmem); void shmem_fetch_response(struct scmi_shared_mem __iomem *shmem, struct scmi_xfer *xfer); diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c index 94be633b55a0..985775f210f9 100644 --- a/drivers/firmware/arm_scmi/driver.c +++ b/drivers/firmware/arm_scmi/driver.c @@ -2013,6 +2013,7 @@ static int scmi_chan_setup(struct scmi_info *info, struct device *dev, return -ENOMEM; cinfo->dev = dev; + cinfo->rx_timeout_ms = info->desc->max_rx_timeout_ms; ret = info->desc->ops->chan_setup(cinfo, info->dev, tx); if (ret) diff --git a/drivers/firmware/arm_scmi/mailbox.c b/drivers/firmware/arm_scmi/mailbox.c index 08ff4d110beb..1e40cb035044 100644 --- a/drivers/firmware/arm_scmi/mailbox.c +++ b/drivers/firmware/arm_scmi/mailbox.c @@ -36,7 +36,7 @@ static void tx_prepare(struct mbox_client *cl, void *m) { struct scmi_mailbox *smbox = client_to_scmi_mailbox(cl); - shmem_tx_prepare(smbox->shmem, m); + shmem_tx_prepare(smbox->shmem, m, smbox->cinfo); } static void rx_callback(struct mbox_client *cl, void *m) diff --git a/drivers/firmware/arm_scmi/optee.c b/drivers/firmware/arm_scmi/optee.c index f42dad997ac9..2a7aeab40e54 100644 --- a/drivers/firmware/arm_scmi/optee.c +++ b/drivers/firmware/arm_scmi/optee.c @@ -498,7 +498,7 @@ static int scmi_optee_send_message(struct scmi_chan_info *cinfo, msg_tx_prepare(channel->req.msg, xfer); ret = invoke_process_msg_channel(channel, msg_command_size(xfer)); } else { - shmem_tx_prepare(channel->req.shmem, xfer); + shmem_tx_prepare(channel->req.shmem, xfer, cinfo); ret = invoke_process_smt_channel(channel); } diff --git a/drivers/firmware/arm_scmi/shmem.c b/drivers/firmware/arm_scmi/shmem.c index 0e3eaea5d852..1dfe534b8518 100644 --- a/drivers/firmware/arm_scmi/shmem.c +++ b/drivers/firmware/arm_scmi/shmem.c @@ -5,10 +5,13 @@ * Copyright (C) 2019 ARM Ltd. */ +#include <linux/ktime.h> #include <linux/io.h> #include <linux/processor.h> #include <linux/types.h> +#include <asm-generic/bug.h> + #include "common.h" /* @@ -30,16 +33,36 @@ struct scmi_shared_mem { }; void shmem_tx_prepare(struct scmi_shared_mem __iomem *shmem, - struct scmi_xfer *xfer) + struct scmi_xfer *xfer, struct scmi_chan_info *cinfo) { + ktime_t stop; + /* * Ideally channel must be free by now unless OS timeout last * request and platform continued to process the same, wait * until it releases the shared memory, otherwise we may endup - * overwriting its response with new message payload or vice-versa + * overwriting its response with new message payload or vice-versa. + * Giving up anyway after twice the expected channel timeout so as + * not to bail-out on intermittent issues where the platform is + * occasionally a bit slower to answer. + * + * Note that after a timeout is detected we bail-out and carry on but + * the transport functionality is probably permanently compromised: + * this is just to ease debugging and avoid complete hangs on boot + * due to a misbehaving SCMI firmware. */ - spin_until_cond(ioread32(&shmem->channel_status) & - SCMI_SHMEM_CHAN_STAT_CHANNEL_FREE); + stop = ktime_add_ms(ktime_get(), 2 * cinfo->rx_timeout_ms); + spin_until_cond((ioread32(&shmem->channel_status) & + SCMI_SHMEM_CHAN_STAT_CHANNEL_FREE) || + ktime_after(ktime_get(), stop)); + if (!(ioread32(&shmem->channel_status) & + SCMI_SHMEM_CHAN_STAT_CHANNEL_FREE)) { + WARN_ON_ONCE(1); + dev_err(cinfo->dev, + "Timeout waiting for a free TX channel !\n"); + return; + } + /* Mark channel busy + clear error */ iowrite32(0x0, &shmem->channel_status); iowrite32(xfer->hdr.poll_completion ? 0 : SCMI_SHMEM_FLAG_INTR_ENABLED, diff --git a/drivers/firmware/arm_scmi/smc.c b/drivers/firmware/arm_scmi/smc.c index 745acfdd0b3d..87a7b13cf868 100644 --- a/drivers/firmware/arm_scmi/smc.c +++ b/drivers/firmware/arm_scmi/smc.c @@ -188,7 +188,7 @@ static int smc_send_message(struct scmi_chan_info *cinfo, */ smc_channel_lock_acquire(scmi_info, xfer); - shmem_tx_prepare(scmi_info->shmem, xfer); + shmem_tx_prepare(scmi_info->shmem, xfer, cinfo); arm_smccc_1_1_invoke(scmi_info->func_id, 0, 0, 0, 0, 0, 0, 0, &res); |