Attempt to acquire the APCS IPC through the mailbox framework and fall
back to the old syscon based approach, to allow us to move away from
using the syscon.
Reviewed-by: Arun Kumar Neelakantam <aneela@xxxxxxxxxxxxxx>
Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
---
Changes since v2:
- Added comment about mbox_send_message() return value.
.../devicetree/bindings/soc/qcom/qcom,smd.txt | 8 ++-
drivers/rpmsg/Kconfig | 1 +
drivers/rpmsg/qcom_smd.c | 67 ++++++++++++++++------
3 files changed, 56 insertions(+), 20 deletions(-)
diff --git a/Documentation/devicetree/bindings/soc/qcom/qcom,smd.txt b/Documentation/devicetree/bindings/soc/qcom/qcom,smd.txt
index ea1dc75ec9ea..234ae2256501 100644
--- a/Documentation/devicetree/bindings/soc/qcom/qcom,smd.txt
+++ b/Documentation/devicetree/bindings/soc/qcom/qcom,smd.txt
@@ -22,9 +22,15 @@ The edge is described by the following properties:
Definition: should specify the IRQ used by the remote processor to
signal this processor about communication related updates
-- qcom,ipc:
+- mboxes:
Usage: required
Value type: <prop-encoded-array>
+ Definition: reference to the associated doorbell in APCS, as described
+ in mailbox/mailbox.txt
+
+- qcom,ipc:
+ Usage: required, unless mboxes is specified
+ Value type: <prop-encoded-array>
Definition: three entries specifying the outgoing ipc bit used for
signaling the remote processor:
- phandle to a syscon node representing the apcs registers
diff --git a/drivers/rpmsg/Kconfig b/drivers/rpmsg/Kconfig
index 0fe6eac46512..2e4fb4ffd562 100644
--- a/drivers/rpmsg/Kconfig
+++ b/drivers/rpmsg/Kconfig
@@ -39,6 +39,7 @@ config RPMSG_QCOM_GLINK_SMEM
config RPMSG_QCOM_SMD
tristate "Qualcomm Shared Memory Driver (SMD)"
+ depends on MAILBOX
depends on QCOM_SMEM
select RPMSG
help
diff --git a/drivers/rpmsg/qcom_smd.c b/drivers/rpmsg/qcom_smd.c
index bc0b30657230..3ff271a44bef 100644
--- a/drivers/rpmsg/qcom_smd.c
+++ b/drivers/rpmsg/qcom_smd.c
@@ -14,6 +14,7 @@
#include <linux/interrupt.h>
#include <linux/io.h>
+#include <linux/mailbox_client.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of_irq.h>
@@ -107,6 +108,8 @@ static const struct {
* @ipc_regmap: regmap handle holding the outgoing ipc register
* @ipc_offset: offset within @ipc_regmap of the register for ipc
* @ipc_bit: bit in the register at @ipc_offset of @ipc_regmap
+ * @mbox_client: mailbox client handle
+ * @mbox_chan: apcs ipc mailbox channel handle
* @channels: list of all channels detected on this edge
* @channels_lock: guard for modifications of @channels
* @allocated: array of bitmaps representing already allocated channels
@@ -129,6 +132,9 @@ struct qcom_smd_edge {
int ipc_offset;
int ipc_bit;
+ struct mbox_client mbox_client;
+ struct mbox_chan *mbox_chan;
+
struct list_head channels;
spinlock_t channels_lock;
@@ -366,7 +372,17 @@ static void qcom_smd_signal_channel(struct qcom_smd_channel *channel)
{
struct qcom_smd_edge *edge = channel->edge;
- regmap_write(edge->ipc_regmap, edge->ipc_offset, BIT(edge->ipc_bit));
+ if (edge->mbox_chan) {
+ /*
+ * We can ignore a failing mbox_send_message() as the only
+ * possible cause is that the FIFO in the framework is full of
+ * other writes to the same bit.
+ */
+ mbox_send_message(edge->mbox_chan, NULL);
+ mbox_client_txdone(edge->mbox_chan, 0);
+ } else {
+ regmap_write(edge->ipc_regmap, edge->ipc_offset, BIT(edge->ipc_bit));
+ }
}
/*
@@ -1326,27 +1342,37 @@ static int qcom_smd_parse_edge(struct device *dev,
key = "qcom,remote-pid";
of_property_read_u32(node, key, &edge->remote_pid);
- syscon_np = of_parse_phandle(node, "qcom,ipc", 0);
- if (!syscon_np) {
- dev_err(dev, "no qcom,ipc node\n");
- return -ENODEV;
- }
+ edge->mbox_client.dev = dev;
+ edge->mbox_client.knows_txdone = true;
+ edge->mbox_chan = mbox_request_channel(&edge->mbox_client, 0);
+ if (IS_ERR(edge->mbox_chan)) {
+ if (PTR_ERR(edge->mbox_chan) != -ENODEV)
+ return PTR_ERR(edge->mbox_chan);
- edge->ipc_regmap = syscon_node_to_regmap(syscon_np);
- if (IS_ERR(edge->ipc_regmap))
- return PTR_ERR(edge->ipc_regmap);
+ edge->mbox_chan = NULL;
- key = "qcom,ipc";
- ret = of_property_read_u32_index(node, key, 1, &edge->ipc_offset);
- if (ret < 0) {
- dev_err(dev, "no offset in %s\n", key);
- return -EINVAL;
- }
+ syscon_np = of_parse_phandle(node, "qcom,ipc", 0);
+ if (!syscon_np) {
+ dev_err(dev, "no qcom,ipc node\n");
+ return -ENODEV;
+ }
- ret = of_property_read_u32_index(node, key, 2, &edge->ipc_bit);
- if (ret < 0) {
- dev_err(dev, "no bit in %s\n", key);
- return -EINVAL;
+ edge->ipc_regmap = syscon_node_to_regmap(syscon_np);
+ if (IS_ERR(edge->ipc_regmap))
+ return PTR_ERR(edge->ipc_regmap);
+
+ key = "qcom,ipc";
+ ret = of_property_read_u32_index(node, key, 1, &edge->ipc_offset);
+ if (ret < 0) {
+ dev_err(dev, "no offset in %s\n", key);
+ return -EINVAL;
+ }
+
+ ret = of_property_read_u32_index(node, key, 2, &edge->ipc_bit);
+ if (ret < 0) {
+ dev_err(dev, "no bit in %s\n", key);
+ return -EINVAL;
+ }
}
ret = of_property_read_string(node, "label", &edge->name);
@@ -1452,6 +1478,8 @@ struct qcom_smd_edge *qcom_smd_register_edge(struct device *parent,
return edge;
unregister_dev:
+ if (!IS_ERR_OR_NULL(edge->mbox_chan))
+ mbox_free_channel(edge->mbox_chan);
put_device(&edge->dev);
return ERR_PTR(ret);
}
@@ -1480,6 +1508,7 @@ int qcom_smd_unregister_edge(struct qcom_smd_edge *edge)
if (ret)
dev_warn(&edge->dev, "can't remove smd device: %d\n", ret);
+ mbox_free_channel(edge->mbox_chan);
device_unregister(&edge->dev);
return 0;
--
2.16.2
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
