[PATCH v4 03/13] firmware: arm_scmi: Add notifications support in transport layer

Cristian Marussi
2020-03-04T16:26:43Z

Add common transport-layer methods to:
- fetch a notification instead of a response
- clear a pending notification

Add also all the needed support in mailbox/shmem transports.

Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
---
drivers/firmware/arm_scmi/common.h | 8 ++++++++
drivers/firmware/arm_scmi/mailbox.c | 17 +++++++++++++++++
drivers/firmware/arm_scmi/shmem.c | 15 +++++++++++++++
3 files changed, 40 insertions(+)

diff --git a/drivers/firmware/arm_scmi/common.h b/drivers/firmware/arm_scmi/common.h
index 5ac06469b01c..3c2e5d0d7b68 100644
--- a/drivers/firmware/arm_scmi/common.h
+++ b/drivers/firmware/arm_scmi/common.h
@@ -178,6 +178,8 @@ struct scmi_chan_info {
* @send_message: Callback to send a message
* @mark_txdone: Callback to mark tx as done
* @fetch_response: Callback to fetch response
+ * @fetch_notification: Callback to fetch notification
+ * @clear_notification: Callback to clear a pending notification
* @poll_done: Callback to poll transfer status
*/
struct scmi_transport_ops {
@@ -190,6 +192,9 @@ struct scmi_transport_ops {
void (*mark_txdone)(struct scmi_chan_info *cinfo, int ret);
void (*fetch_response)(struct scmi_chan_info *cinfo,
struct scmi_xfer *xfer);
+ void (*fetch_notification)(struct scmi_chan_info *cinfo,
+ size_t max_len, struct scmi_xfer *xfer);
+ void (*clear_notification)(struct scmi_chan_info *cinfo);
bool (*poll_done)(struct scmi_chan_info *cinfo, struct scmi_xfer *xfer);
};

@@ -222,5 +227,8 @@ void shmem_tx_prepare(struct scmi_shared_mem __iomem *shmem,
u32 shmem_read_header(struct scmi_shared_mem __iomem *shmem);
void shmem_fetch_response(struct scmi_shared_mem __iomem *shmem,
struct scmi_xfer *xfer);
+void shmem_fetch_notification(struct scmi_shared_mem __iomem *shmem,
+ size_t max_len, struct scmi_xfer *xfer);
+void shmem_clear_notification(struct scmi_shared_mem __iomem *shmem);
bool shmem_poll_done(struct scmi_shared_mem __iomem *shmem,
struct scmi_xfer *xfer);
diff --git a/drivers/firmware/arm_scmi/mailbox.c b/drivers/firmware/arm_scmi/mailbox.c
index 73077bbc4ad9..19ee058f9f44 100644
--- a/drivers/firmware/arm_scmi/mailbox.c
+++ b/drivers/firmware/arm_scmi/mailbox.c
@@ -158,6 +158,21 @@ static void mailbox_fetch_response(struct scmi_chan_info *cinfo,
shmem_fetch_response(smbox->shmem, xfer);
}

+static void mailbox_fetch_notification(struct scmi_chan_info *cinfo,
+ size_t max_len, struct scmi_xfer *xfer)
+{
+ struct scmi_mailbox *smbox = cinfo->transport_info;
+
+ shmem_fetch_notification(smbox->shmem, max_len, xfer);
+}
+
+static void mailbox_clear_notification(struct scmi_chan_info *cinfo)
+{
+ struct scmi_mailbox *smbox = cinfo->transport_info;
+
+ shmem_clear_notification(smbox->shmem);
+}
+
static bool
mailbox_poll_done(struct scmi_chan_info *cinfo, struct scmi_xfer *xfer)
{
@@ -173,6 +188,8 @@ static struct scmi_transport_ops scmi_mailbox_ops = {
.send_message = mailbox_send_message,
.mark_txdone = mailbox_mark_txdone,
.fetch_response = mailbox_fetch_response,
+ .fetch_notification = mailbox_fetch_notification,
+ .clear_notification = mailbox_clear_notification,
.poll_done = mailbox_poll_done,
};

diff --git a/drivers/firmware/arm_scmi/shmem.c b/drivers/firmware/arm_scmi/shmem.c
index ca0ffd302ea2..e1ab05be90e3 100644
--- a/drivers/firmware/arm_scmi/shmem.c
+++ b/drivers/firmware/arm_scmi/shmem.c
@@ -67,6 +67,21 @@ void shmem_fetch_response(struct scmi_shared_mem __iomem *shmem,
memcpy_fromio(xfer->rx.buf, shmem->msg_payload + 4, xfer->rx.len);
}

+void shmem_fetch_notification(struct scmi_shared_mem __iomem *shmem,
+ size_t max_len, struct scmi_xfer *xfer)
+{
+ /* Skip only the length of header in shmem area i.e 4 bytes */
+ xfer->rx.len = min_t(size_t, max_len, ioread32(&shmem->length) - 4);
+
+ /* Take a copy to the rx buffer.. */
+ memcpy_fromio(xfer->rx.buf, shmem->msg_payload, xfer->rx.len);
+}
+
+void shmem_clear_notification(struct scmi_shared_mem __iomem *shmem)
+{
+ iowrite32(SCMI_SHMEM_CHAN_STAT_CHANNEL_FREE, &shmem->channel_status);
+}
+
bool shmem_poll_done(struct scmi_shared_mem __iomem *shmem,
struct scmi_xfer *xfer)
{
--
2.17.1