SK-AM62P-LP: CAN Interface Not Visible After Enabling via Device Tree Overlay

Bibin Robint

Prodigy 10 points

Part Number: SK-AM62P-LP
Other Parts Discussed in Thread: AM62P

Tool/software:

Dear Expert,

I tried to enable CAN via a device tree overlay by following the Android 15 documentation:

software-dl.ti.com/.../Application_Notes_dtbo_support.html

I used the following commands:

After the device booted successfully, I could not find the CAN interface in the ip link show list.

am62p:/ # ip link show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: dummy0: <BROADCAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/ether 7e:e0:7f:9f:22:00 brd ff:ff:ff:ff:ff:ff
3: ifb0: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 32
link/ether ce:95:53:a0:98:d7 brd ff:ff:ff:ff:ff:ff
4: ifb1: <BROADCAST,NOARP> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 32
link/ether 02:3d:db:d9:3f:ed brd ff:ff:ff:ff:ff:ff
5: tunl0@NONE: <NOARP> mtu 1480 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ipip 0.0.0.0 brd 0.0.0.0
6: gre0@NONE: <NOARP> mtu 1476 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/gre 0.0.0.0 brd 0.0.0.0
7: gretap0@NONE: <BROADCAST,MULTICAST> mtu 1462 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether 00:00:00:00:00:00 brd ff:ff:ff:ff:ff:ff
8: erspan0@NONE: <BROADCAST,MULTICAST> mtu 1450 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether 00:00:00:00:00:00 brd ff:ff:ff:ff:ff:ff
9: ip_vti0@NONE: <NOARP> mtu 1480 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ipip 0.0.0.0 brd 0.0.0.0
10: ip6_vti0@NONE: <NOARP> mtu 1364 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/tunnel6 :: brd ::
11: sit0@NONE: <NOARP> mtu 1480 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/sit 0.0.0.0 brd 0.0.0.0
12: ip6tnl0@NONE: <NOARP> mtu 1452 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/tunnel6 :: brd ::
13: ip6gre0@NONE: <NOARP> mtu 1448 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/gre6 00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00 brd 00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00
14: eth0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether c0:d6:0a:f9:6a:db brd ff:ff:ff:ff:ff:ff
15: eth1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether 2e:c7:a4:1c:83:00 brd ff:ff:ff:ff:ff:ff

Best Regards,

Bibin Robin

1 month ago

0 Varun C 1 month ago

TI__Prodigy 180 points

Hi,

Could you please confirm whether you are using Linux or MCU+,RTOS, Bare Metal domain ?

0 Bibin Robint 1 month ago in reply to Varun C

Prodigy 10 points

i am using android 15

0 Bibin Robint 1 month ago in reply to Bibin Robint

Prodigy 10 points

Hi,
looking forward for your response.

Regards,
Bibin

0 Bibin Robint 1 month ago in reply to Bibin Robint

Prodigy 10 points

Hi Varun,

I wanted to follow up on my previous question posted a few days ago about Device Tree Overlay. I understand you may be busy, but your input would be really helpful for my project.

Regards,

Bibin

0 Bibin Robint 1 month ago in reply to Bibin Robint

Prodigy 10 points

hi Divyansh Mittal .Could you please check ?

0 Bibin Robint 1 month ago in reply to Bibin Robint

Prodigy 10 points

Hi Varun C , Divyansh Mittal

these are the log mesage of dmesg -w

130|console:/vendor_dlkm/lib/modules # dmesg -w
[ 1167.467962] m_can: Unknown symbol alloc_candev_mqs (err -2)
[ 1167.468035] m_can: Unknown symbol free_candev (err -2)
[ 1167.468071] m_can: Unknown symbol can_rx_offload_add_manual (err -2)
[ 1167.468117] m_can: Unknown symbol can_rx_offload_del (err -2)
[ 1167.468144] m_can: Unknown symbol of_can_transceiver (err -2)
[ 1167.468169] m_can: Protected symbol: irq_wake_thread (err -13)
[ 1167.468193] m_can: Unknown symbol register_candev (err -2)
[ 1167.468215] m_can: Unknown symbol unregister_candev (err -2)
[ 1167.468287] m_can: Unknown symbol can_rx_offload_get_echo_skb_queue_timestamp (err -2)
[ 1167.468304] m_can: Unknown symbol can_get_echo_skb (err -2)
[ 1167.468319] m_can: Unknown symbol can_rx_offload_threaded_irq_finish (err -2)
[ 1167.468337] m_can: Unknown symbol alloc_can_err_skb (err -2)
[ 1167.468352] m_can: Unknown symbol can_rx_offload_queue_timestamp (err -2)
[ 1167.468373] m_can: Unknown symbol alloc_can_skb (err -2)
[ 1167.468542] m_can: Unknown symbol alloc_canfd_skb (err -2)
[ 1167.468573] m_can: Unknown symbol can_fd_dlc2len (err -2)
[ 1167.468634] m_can: Unknown symbol can_bus_off (err -2)
[ 1167.468656] m_can: Unknown symbol can_free_echo_skb (err -2)
[ 1167.468695] m_can: Unknown symbol open_candev (err -2)
[ 1167.468711] m_can: Unknown symbol can_rx_offload_enable (err -2)
[ 1167.468777] m_can: Unknown symbol close_candev (err -2)
[ 1167.468799] m_can: Unknown symbol can_dropped_invalid_skb (err -2)
[ 1167.468815] m_can: Unknown symbol can_skb_get_frame_len (err -2)
[ 1167.468856] m_can: Unknown symbol can_fd_len2dlc (err -2)
[ 1167.468880] m_can: Unknown symbol can_put_echo_skb (err -2)
[ 1167.468915] m_can: Unknown symbol can_change_mtu (err -2)

[ 1218.426865] m_can_platform: Unknown symbol m_can_class_allocate_dev (err -2)
[ 1218.426910] m_can_platform: Unknown symbol m_can_class_get_clocks (err -2)
[ 1218.426991] m_can_platform: Unknown symbol m_can_class_register (err -2)
[ 1218.427012] m_can_platform: Unknown symbol m_can_class_free_dev (err -2)
[ 1218.427027] m_can_platform: Unknown symbol m_can_class_unregister (err -2)
[ 1218.427059] m_can_platform: Unknown symbol m_can_class_suspend (err -2)
[ 1218.427075] m_can_platform: Unknown symbol m_can_class_resume (err -2)

Regards,

Bibin Robin

0 Maxime Fournier 1 month ago in reply to Bibin Robint

TI__Prodigy 170 points

Hello,

sorry for the delay,

Just to confirm, given the timing of the error logs, you are trying to load the driver manually? The driver should load automatically with the device tree overlay.

The errors indicate that the can driver is prevented from loading due to a gki symbol error.

It will probably require patching and rebuilding the kernel to bypass the symbol error. The error will be fixed in the next android release.

We will get back to you with more information.

0 Bibin Robint 1 month ago in reply to Maxime Fournier

Prodigy 10 points

Hi Maxime,

yes these are the logs when i tried to load driver manually, but when i tried using DTBO I got errors like

6.109745][ T168] ueventd: Failed to insmod '/vendor/lib/modules/can-dev.ko' with args '': Permission denied
[ 6.119968][ T168] ueventd: LoadWithAliases was unable to load /vendor/lib/modules/can-dev.ko, tried: can_dev
[ 6.130255][ T168] ueventd: LoadWithAliases was unable to load of:NcanT(null)Cbosch,m_can, tried: m_can_platform, of:NcanT(null)Cbosch,m_can

6.190704][ T167] can_dev: exports protected symbol can_eth_ioctl_hwts
[ 6.256785][ T167] ueventd: Failed to insmod '/vendor/lib/modules/can-dev.ko' with args '': Permission denied
[ 6.266944][ T167] ueventd: LoadWithAliases was unable to load /vendor/lib/modules/can-dev.ko, tried: can_dev
[ 6.266988][ T167] ueventd: LoadWithAliases was unable to load of:NcanT(null)Cbosch,m_can, tried: m_can_platform, of:NcanT(null)Cbosch,m_can

Regards,

Bibin

+1 Maxime Fournier 1 month ago in reply to Bibin Robint

TI__Prodigy 170 points

Hello, yes unfortunately a kernel rebuild is required to get the can drivers to load.

Here is the patch:

Fullscreen update_symbols_list_can_drivers.diff Download

diff --git a/android/abi_gki_aarch64_ti b/android/abi_gki_aarch64_ti
index fc0e030a5832..c404a50b8ff4 100644
--- a/android/abi_gki_aarch64_ti
+++ b/android/abi_gki_aarch64_ti
@@ -2,6 +2,11 @@
 # commonly used symbols
   add_timer
   __alloc_pages
+  alloc_can_err_skb
+  alloc_can_skb
+  alloc_candev_mqs
+  alloc_canfd_skb
+  alloc_canxl_skb
   alloc_workqueue
   alt_cb_patch_nops
   __arch_copy_from_user
@@ -13,6 +18,8 @@
   bpf_trace_run5
   cache_line_size
   call_rcu
+  can_bus_off
+  can_change_mtu
   __check_object_size
   clk_disable
   clk_enable
@@ -416,23 +423,37 @@
   call_netdevice_notifiers
   call_switchdev_notifiers
   can_bus_off
+  can_eth_ioctl_hwts
+  can_ethtool_op_get_ts_info_hwts
   cancel_delayed_work
   cancel_delayed_work_sync
   cancel_work
   cancel_work_sync
   can_change_mtu
+  can_change_state
   can_dropped_invalid_skb
   can_fd_dlc2len
   can_fd_len2dlc
   can_free_echo_skb
   can_get_echo_skb
+  can_get_state_str
   can_put_echo_skb
+  can_rx_offload_add_fifo
   can_rx_offload_add_manual
+  can_rx_offload_add_timestamp
   can_rx_offload_del
   can_rx_offload_enable
+  can_rx_offload_get_echo_skb_queue_tail
   can_rx_offload_get_echo_skb_queue_timestamp
+  can_rx_offload_irq_finish
+  can_rx_offload_irq_offload_fifo
+  can_rx_offload_irq_offload_timestamp
+  can_rx_offload_queue_tail
   can_rx_offload_queue_timestamp
   can_rx_offload_threaded_irq_finish
+  can_rx_register
+  can_rx_unregister
+  can_skb_get_frame_len
   capable
   carveout_dma_heap_to_paddr
   cdc_parse_cdc_header
@@ -451,6 +472,7 @@
   class_for_each_device
   class_register
   class_unregister
+  close_candev
   __ClearPageMovable
   clk_bulk_disable
   clk_bulk_enable
@@ -1256,6 +1278,7 @@
   irq_set_irqchip_state
   irq_set_irq_type
   irq_set_irq_wake
+  irq_wake_thread
   jiffies_to_msecs
   jiffies_to_usecs
   kasprintf
@@ -1930,6 +1953,7 @@
   rtnl_unlock
   rtnl_unregister
   rtnl_unregister_all
+  safe_candev_priv
   scatterwalk_map_and_copy
   schedule_timeout_interruptible
   schedule_timeout_uninterruptible
diff --git a/android/abi_gki_protected_exports_aarch64 b/android/abi_gki_protected_exports_aarch64
index 02a37702f3a1..276de2356912 100644
--- a/android/abi_gki_protected_exports_aarch64
+++ b/android/abi_gki_protected_exports_aarch64
@@ -16,11 +16,6 @@ __regmap_init_ram
 __regmap_init_raw_ram
 __traceiter_9p_fid_ref
 __tracepoint_9p_fid_ref
-alloc_can_err_skb
-alloc_can_skb
-alloc_candev_mqs
-alloc_canfd_skb
-alloc_canxl_skb
 btbcm_check_bdaddr
 btbcm_finalize
 btbcm_initialize
@@ -30,37 +25,9 @@ btbcm_set_bdaddr
 btbcm_setup_apple
 btbcm_setup_patchram
 btbcm_write_pcm_int_params
-can_bus_off
-can_change_mtu
-can_change_state
-can_dropped_invalid_skb
-can_eth_ioctl_hwts
-can_ethtool_op_get_ts_info_hwts
-can_fd_dlc2len
-can_fd_len2dlc
-can_free_echo_skb
-can_get_echo_skb
-can_get_state_str
 can_proto_register
 can_proto_unregister
-can_put_echo_skb
-can_rx_offload_add_fifo
-can_rx_offload_add_manual
-can_rx_offload_add_timestamp
-can_rx_offload_del
-can_rx_offload_enable
-can_rx_offload_get_echo_skb_queue_tail
-can_rx_offload_get_echo_skb_queue_timestamp
-can_rx_offload_irq_finish
-can_rx_offload_irq_offload_fifo
-can_rx_offload_irq_offload_timestamp
-can_rx_offload_queue_tail
-can_rx_offload_queue_timestamp
-can_rx_offload_threaded_irq_finish
-can_rx_register
-can_rx_unregister
 can_send
-can_skb_get_frame_len
 can_sock_destruct
 cdc_ncm_bind_common
 cdc_ncm_change_mtu
@@ -73,10 +40,8 @@ cdc_ncm_rx_verify_nth32
 cdc_ncm_select_altsetting
 cdc_ncm_tx_fixup
 cdc_ncm_unbind
-close_candev
 do_trace_9p_fid_get
 do_trace_9p_fid_put
-free_candev
 generic_mii_ioctl
 h4_recv_buf
 hci_alloc_dev_priv
@@ -249,8 +214,6 @@ nl802154_beaconing_done
 nl802154_scan_done
 nl802154_scan_event
 nl802154_scan_started
-of_can_transceiver
-open_candev
 p9_client_attach
 p9_client_begin_disconnect
 p9_client_cb
@@ -317,10 +280,8 @@ qca_send_pre_shutdown_cmd
 qca_set_bdaddr
 qca_set_bdaddr_rome
 qca_uart_setup
-register_candev
 register_pppox_proto
 rtl8152_get_version
-safe_candev_priv
 slhc_compress
 slhc_free
 slhc_init
@@ -331,7 +292,6 @@ tipc_dump_done
 tipc_dump_start
 tipc_nl_sk_walk
 tipc_sk_fill_sock_diag
-unregister_candev
 unregister_pppox_proto
 usb_serial_claim_interface
 usb_serial_deregister_drivers

You will need to rebuild the kernel and the android BSP to deploy it. Please follow the documentation: https://software-dl.ti.com/processor-sdk-android/esd/AM62PX/latest/docs/android/Foundational_Components_Kernel.html

The patch applies in the "common" directory of the kernel root tree after the repo sync command.

Please let me know if this worked.

Thank you.

Regards,

Maxime

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SK-AM62P-LP: CAN Interface Not Visible After Enabling via Device Tree Overlay