firmware: scmi: Validate device tree node before setup channel

SCMI base protocol device does not have a device tree, it should use and
need to use the agent base channel.

For scmi_base.[x], there is no real device tree node for it. ofnode_null() is
assigned as the device tree node for scmi base protocol device:
commit 7eb4eb541c14 ("firmware: scmi: install base protocol to SCMI agent")

However with recent update in commit 0535e46d55d7
("scripts/dtc: Update to upstream version v1.7.2-35-g52f07dcca47c"),
SPL panic in fdt_check_node_offset_()->fdt_next_tag(), because offset is -1
and SPL_OF_LIBFDT_ASSUME_MASK is 0xFF.

So add a check in x_get_channel() to validate the protocol devices'
ofnode.

Reported-by: Ye Li <ye.li@nxp.com>
Closes: https://lore.kernel.org/u-boot/939a9696-27fa-45a1-b428-feffe21ac6d5@oss.nxp.com/
Signed-off-by: Peng Fan <peng.fan@nxp.com>

diff --git a/drivers/firmware/scmi/mailbox_agent.c b/drivers/firmware/scmi/mailbox_agent.c
index 16a82f55ab7f7550e7744066cd640b0c439f75eb..cda94565de56d0d89615ef03ce665c23001bc650 100644 (file)
--- a/drivers/firmware/scmi/mailbox_agent.c
+++ b/drivers/firmware/scmi/mailbox_agent.c
@@ -101,7 +101,7 @@ static int scmi_mbox_get_channel(struct udevice *dev,
        struct scmi_mbox_channel *chan;
        int ret;
 
-       if (!dev_read_prop(protocol, "shmem", NULL)) {
+       if (!dev_has_ofnode(protocol) || !dev_read_prop(protocol, "shmem", NULL)) {
                /* Uses agent base channel */
                *channel = container_of(base_chan, struct scmi_channel, ref);
 

diff --git a/drivers/firmware/scmi/optee_agent.c b/drivers/firmware/scmi/optee_agent.c
index 631625d715bfaaf71578da69a0dd4f853d056b48..7170bd1e682061c42a031c327594a4088584f4ca 100644 (file)
--- a/drivers/firmware/scmi/optee_agent.c
+++ b/drivers/firmware/scmi/optee_agent.c
@@ -331,7 +331,8 @@ static int scmi_optee_get_channel(struct udevice *dev,
        u32 channel_id;
        int ret;
 
-       if (dev_read_u32(protocol, "linaro,optee-channel-id", &channel_id)) {
+       if (!dev_has_ofnode(protocol) ||
+           dev_read_u32(protocol, "linaro,optee-channel-id", &channel_id)) {
                /* Uses agent base channel */
                *channel = container_of(base_chan, struct scmi_channel, ref);