summaryrefslogtreecommitdiff
path: root/drivers/firmware
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/firmware')
-rw-r--r--drivers/firmware/arm_scmi/common.h4
-rw-r--r--drivers/firmware/arm_scmi/driver.c1
-rw-r--r--drivers/firmware/arm_scmi/mailbox.c2
-rw-r--r--drivers/firmware/arm_scmi/optee.c2
-rw-r--r--drivers/firmware/arm_scmi/shmem.c31
-rw-r--r--drivers/firmware/arm_scmi/smc.c2
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);