Both OMAP5 and sun6i/sun7i SoCs share this UART driver for early_printk.
Signed-off-by: Chen Baozi <baozich@gmail.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
With the help of the previous patches add a stanza to
xen/arch/arm/Rules.mk to specify the UART configuration of the
Calxeda Midway machine.
The information has been taken from the Linux kernel's .dts file.
This can be enabled by adding "CONFIG_EARLY_PRINTK=midway" to
Config.mk.
Signed-off-by: Andre Przywara <andre.przywara@calxeda.com>
Reviewed-by: Julien Grall <julien.grall@linaro.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Though the ARM Fastmodel software emulator mimics a Versatile Express
board, the boot process is different compared to the real hardware,
so the early printk differs slightly. Create a new early-printk
target to model this correctly.
Signed-off-by: Andre Przywara <andre.przywara@calxeda.com>
Reviewed-by: Julien Grall <julien.grall@linaro.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
The UART memory mapped base address is currently hardcoded in the
early-printk UART driver, which denies the driver to be used by
two machines with a different mapping.
Move this definition out to xen/arch/arm/Rules.mk, allowing easier
user access and later sharing of the driver.
Signed-off-by: Andre Przywara <andre.przywara@calxeda.com>
Reviewed-by: Julien Grall <julien.grall@linaro.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
While it seems obvious to initialize the UART before using it, chances
are that some firmware code or the bootloader already did this.
So it may actually be a good idea to skip the initialization, in fact
this fixes early printk on my TC2 Versatile Express.
So provide an option in xen/arch/arm/Rules.mk to only initialize the
UART when needed.
Signed-off-by: Andre Przywara <andre.przywara@calxeda.com>
Reviewed-by: Julien Grall <julien.grall@linaro.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
For early-printk the used baud rate was hardcoded in the code, using
precalculated divisor values.
Let the calculation of these values be done by the preprocessor and
use a human readable value in xen/arch/arm/Rules.mk to drive this.
Signed-off-by: Andre Przywara <andre.przywara@calxeda.com>
Reviewed-by: Julien Grall <julien.grall@linaro.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Add CONFIG_EARLY_PRINTK options in configs/arm{32,64}.mk to let the user
to choose if he wants to have early output, ie before the console is initialized.
This code is specific for each UART. When CONFIG_EARLY_PRINTK is enabled,
Xen will only be able to run on a board with this UART.
If a developper wants to add support for a new UART, he must implement the
following assembly macro/define:
- EALY_UART_BASE_ADDRESS: variable which contains the physical base address
for the UART
- early_uart_init: initialize the UART
- early_uart_ready: check and wait until the UART can transmit a new
character
- early_uart_transmit: transmit a character
For more details about the parameters of each function,
see arm{32,64}/debug-pl011.inc comments.
Signed-off-by: Julien Grall <julien.grall@linaro.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
The bootloader should populate /chosen/modules/module@<N>/ for each
module it wishes to pass to the hypervisor. The content of these nodes
is described in docs/misc/arm/device-tree/booting.txt
Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Chen Baozi
Andre Przywara
Anthony PERARD
Julien Grall
Ian Campbell