[PATCH v2 2/2] firmware: arm_scmi: mailbox: support P2A channel completion
Peng Fan (OSS)
peng.fan at oss.nxp.com
Thu May 9 20:19:48 PDT 2024
From: Peng Fan <peng.fan at nxp.com>
i.MX95 System Manager firmware is fully interrupt driven. The notification
channel needs completion interrupt to drive its notification queue. Without
completion interrupt, the notification will work abnormal.
- Add an optional unidirectional mailbox channel. If the channel flag has
INTR set, and the completion interrupt channel is provided, issue the
mbox message to Platform after the channel is freed.
- Support bidirectional channel completion interrupt.
Signed-off-by: Peng Fan <peng.fan at nxp.com>
---
drivers/firmware/arm_scmi/common.h | 1 +
drivers/firmware/arm_scmi/mailbox.c | 60 +++++++++++++++++++++++++++++++++----
drivers/firmware/arm_scmi/shmem.c | 5 ++++
3 files changed, 60 insertions(+), 6 deletions(-)
diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
index b5ac25dbc1ca..4b8c5250cdb5 100644
--- a/drivers/firmware/arm_scmi/common.h
+++ b/drivers/firmware/arm_scmi/common.h
@@ -326,6 +326,7 @@ void shmem_clear_channel(struct scmi_shared_mem __iomem *shmem);
bool shmem_poll_done(struct scmi_shared_mem __iomem *shmem,
struct scmi_xfer *xfer);
bool shmem_channel_free(struct scmi_shared_mem __iomem *shmem);
+bool shmem_channel_intr_enabled(struct scmi_shared_mem __iomem *shmem);
/* declarations for message passing transports */
struct scmi_msg_payld;
diff --git a/drivers/firmware/arm_scmi/mailbox.c b/drivers/firmware/arm_scmi/mailbox.c
index 615a3b2ad83d..adb69a6a0223 100644
--- a/drivers/firmware/arm_scmi/mailbox.c
+++ b/drivers/firmware/arm_scmi/mailbox.c
@@ -21,6 +21,7 @@
* @cl: Mailbox Client
* @chan: Transmit/Receive mailbox uni/bi-directional channel
* @chan_receiver: Optional Receiver mailbox unidirectional channel
+ * @chan_platform_receiver: Optional Platform Receiver mailbox unidirectional channel
* @cinfo: SCMI channel info
* @shmem: Transmit/Receive shared memory area
*/
@@ -28,6 +29,7 @@ struct scmi_mailbox {
struct mbox_client cl;
struct mbox_chan *chan;
struct mbox_chan *chan_receiver;
+ struct mbox_chan *chan_platform_receiver;
struct scmi_chan_info *cinfo;
struct scmi_shared_mem __iomem *shmem;
};
@@ -91,6 +93,8 @@ static bool mailbox_chan_available(struct device_node *of_node, int idx)
* for replies on the a2p channel. Set as zero if not present.
* @p2a_chan: A reference to the optional p2a channel.
* Set as zero if not present.
+ * @p2a_rx_chan: A reference to the optional p2a completion channel.
+ * Set as zero if not present.
*
* At first, validate the transport configuration as described in terms of
* 'mboxes' and 'shmem', then determin which mailbox channel indexes are
@@ -98,8 +102,8 @@ static bool mailbox_chan_available(struct device_node *of_node, int idx)
*
* Return: 0 on Success or error
*/
-static int mailbox_chan_validate(struct device *cdev,
- int *a2p_rx_chan, int *p2a_chan)
+static int mailbox_chan_validate(struct device *cdev, int *a2p_rx_chan,
+ int *p2a_chan, int *p2a_rx_chan)
{
int num_mb, num_sh, ret = 0;
struct device_node *np = cdev->of_node;
@@ -109,8 +113,9 @@ static int mailbox_chan_validate(struct device *cdev,
dev_dbg(cdev, "Found %d mboxes and %d shmems !\n", num_mb, num_sh);
/* Bail out if mboxes and shmem descriptors are inconsistent */
- if (num_mb <= 0 || num_sh <= 0 || num_sh > 2 || num_mb > 3 ||
- (num_mb == 1 && num_sh != 1) || (num_mb == 3 && num_sh != 2)) {
+ if (num_mb <= 0 || num_sh <= 0 || num_sh > 2 || num_mb > 4 ||
+ (num_mb == 1 && num_sh != 1) || (num_mb == 3 && num_sh != 2) ||
+ (num_mb == 4 && num_sh != 2)) {
dev_warn(cdev,
"Invalid channel descriptor for '%s' - mbs:%d shm:%d\n",
of_node_full_name(np), num_mb, num_sh);
@@ -139,6 +144,7 @@ static int mailbox_chan_validate(struct device *cdev,
case 1:
*a2p_rx_chan = 0;
*p2a_chan = 0;
+ *p2a_rx_chan = 0;
break;
case 2:
if (num_sh == 2) {
@@ -148,10 +154,17 @@ static int mailbox_chan_validate(struct device *cdev,
*a2p_rx_chan = 1;
*p2a_chan = 0;
}
+ *p2a_rx_chan = 0;
break;
case 3:
*a2p_rx_chan = 1;
*p2a_chan = 2;
+ *p2a_rx_chan = 0;
+ break;
+ case 4:
+ *a2p_rx_chan = 1;
+ *p2a_chan = 2;
+ *p2a_rx_chan = 3;
break;
}
}
@@ -166,12 +179,12 @@ static int mailbox_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
struct device *cdev = cinfo->dev;
struct scmi_mailbox *smbox;
struct device_node *shmem;
- int ret, a2p_rx_chan, p2a_chan, idx = tx ? 0 : 1;
+ int ret, a2p_rx_chan, p2a_chan, p2a_rx_chan, idx = tx ? 0 : 1;
struct mbox_client *cl;
resource_size_t size;
struct resource res;
- ret = mailbox_chan_validate(cdev, &a2p_rx_chan, &p2a_chan);
+ ret = mailbox_chan_validate(cdev, &a2p_rx_chan, &p2a_chan, &p2a_rx_chan);
if (ret)
return ret;
@@ -229,6 +242,17 @@ static int mailbox_chan_setup(struct scmi_chan_info *cinfo, struct device *dev,
}
}
+ if (!tx && p2a_rx_chan) {
+ smbox->chan_platform_receiver = mbox_request_channel(cl, p2a_rx_chan);
+ if (IS_ERR(smbox->chan_platform_receiver)) {
+ ret = PTR_ERR(smbox->chan_platform_receiver);
+ if (ret != -EPROBE_DEFER)
+ dev_err(cdev, "failed to request SCMI P2A Receiver mailbox\n");
+ return ret;
+ }
+ }
+
+
cinfo->transport_info = smbox;
smbox->cinfo = cinfo;
@@ -243,9 +267,11 @@ static int mailbox_chan_free(int id, void *p, void *data)
if (smbox && !IS_ERR(smbox->chan)) {
mbox_free_channel(smbox->chan);
mbox_free_channel(smbox->chan_receiver);
+ mbox_free_channel(smbox->chan_platform_receiver);
cinfo->transport_info = NULL;
smbox->chan = NULL;
smbox->chan_receiver = NULL;
+ smbox->chan_platform_receiver = NULL;
smbox->cinfo = NULL;
}
@@ -300,8 +326,30 @@ static void mailbox_fetch_notification(struct scmi_chan_info *cinfo,
static void mailbox_clear_channel(struct scmi_chan_info *cinfo)
{
struct scmi_mailbox *smbox = cinfo->transport_info;
+ struct device *cdev = cinfo->dev;
+ struct mbox_chan *intr;
+ int ret;
shmem_clear_channel(smbox->shmem);
+
+ if (!shmem_channel_intr_enabled(smbox->shmem))
+ return;
+
+ if (smbox->chan_platform_receiver)
+ intr = smbox->chan_platform_receiver;
+ else if (smbox->chan)
+ intr = smbox->chan;
+ else {
+ dev_err(cdev, "Channel INTR wrongly set?\n");
+ return;
+ }
+
+ ret = mbox_send_message(intr, NULL);
+ /* mbox_send_message returns non-negative value on success, so reset */
+ if (ret > 0)
+ ret = 0;
+
+ mbox_client_txdone(intr, ret);
}
static bool
diff --git a/drivers/firmware/arm_scmi/shmem.c b/drivers/firmware/arm_scmi/shmem.c
index 8bf495bcad09..b74e5a740f2c 100644
--- a/drivers/firmware/arm_scmi/shmem.c
+++ b/drivers/firmware/arm_scmi/shmem.c
@@ -128,3 +128,8 @@ bool shmem_channel_free(struct scmi_shared_mem __iomem *shmem)
return (ioread32(&shmem->channel_status) &
SCMI_SHMEM_CHAN_STAT_CHANNEL_FREE);
}
+
+bool shmem_channel_intr_enabled(struct scmi_shared_mem __iomem *shmem)
+{
+ return ioread32(&shmem->flags) & SCMI_SHMEM_FLAG_INTR_ENABLED;
+}
--
2.37.1
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