From: Vabhav Sharma vabhav.sharma@nxp.com
U-Boot DM model probe only single device at a time which is enabled and configured using device tree or platform data method.
PL011 UART IP is SBSA compliant and firmware does the serial port set-up, initialization and let the kernel use UART port for sending and receiving characters.
Normally software talk to one serial port time but some LayerScape platform require all the UART devices enabled in Linux for various use case.
Adding support to probe all enabled serial devices like SBSA compliant PL011 UART ports probe and initialization by firmware.
Signed-off-by: Vabhav Sharma vabhav.sharma@nxp.com Reviewed-by: Stefan Roese sr@denx.de Reviewed-by: Simon Glass sjg@chromium.org -- v5: Incorporated review comments from Sean Anderson - Modified the macro description - Added error check
v3: Incorporated Simon and Stephan review comment - Define generic function uclass_probe_all(enum uclass_id) in drivers/core/uclass.c - Added the function in caller of serial_find_console_or_panic() - Removed repeated sequence with generic function call uclass_probe_all() - Dependent on other patch [PATCH] dm: core: add function uclass_probe_all() to probe all devices
v2: Incorporated Stefan review comment, Update #ifdef with macro if (IS_ENABLED).. --- drivers/serial/Kconfig | 16 ++++++++++++++++ drivers/serial/serial-uclass.c | 9 +++++++++ 2 files changed, 25 insertions(+)
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig index b4805a2..1294943 100644 --- a/drivers/serial/Kconfig +++ b/drivers/serial/Kconfig @@ -134,6 +134,22 @@ config SERIAL_SEARCH_ALL
If unsure, say N.
+config SERIAL_PROBE_ALL + bool "Probe all available serial devices" + depends on DM_SERIAL + default n + help + The serial subsystem only probes for a single serial device, + but does not probe for other remaining serial devices. + With this option set, we make probing and searching for + all available devices optional. + Normally, U-Boot talks to one serial port at a time, but SBSA + compliant UART devices like PL011 require initialization + by firmware and to let the kernel use serial port for sending + and receiving the characters. + + If unsure, say N. + config SPL_DM_SERIAL bool "Enable Driver Model for serial drivers in SPL" depends on DM_SERIAL && SPL_DM diff --git a/drivers/serial/serial-uclass.c b/drivers/serial/serial-uclass.c index f3c25d4..48e0080 100644 --- a/drivers/serial/serial-uclass.c +++ b/drivers/serial/serial-uclass.c @@ -172,6 +172,15 @@ int serial_init(void) /* Called after relocation */ int serial_initialize(void) { + /* Scanning uclass to probe devices */ + if (IS_ENABLED(CONFIG_SERIAL_PROBE_ALL)) { + int ret; + + ret = uclass_probe_all(UCLASS_SERIAL); + if (ret) + return ret; + } + return serial_init(); }