This is needed with the pl011 driver. Before this change it would default
to a shift of 0, however the hardware places the registers at 4-byte
addresses meaning the value should be 2.
This patch fixes this for the pl011 when configured using the fdt. The
other drivers have a default value of 0 to keep this a no-op.
MFC after: 1 week
(class and device) FDT UART. Define second one, UART_FDT_CLASS, for UART
class only.
This paves the way for declaring uart_class data and ofw/fdt compat data
with a uart implementation, rather than needing a big global table of
compat data and weak-symbol declarations of every existing implementation.
Differential Revision: https://reviews.freebsd.org/D1992
Submitted by: Michal Meloun
strings as uart_bus_fdt's probe().
The bus code uses ofw_bus_search_compatible() and that's not an option in
cpu (console) code -- it runs way before the ofw routines are usable. So
the console probe has its own loop to search the table, but now at least
there's only one table to be maintained when new devices are added.
/chosen, following the list of allowed console properties in ePAPR. Also
do not require that stdin be defined and equal to stdout: stdin is
nonstandard (for ePAPR) and console in an unexpected place is after all
better than no console.
The TI uart hardware is ns16550-compatible, except that before it can
be used the clocks and power have to be enabled and a non-standard
mode control register has to be set to put the device in uart mode
(as opposed to irDa or other serial protocols). This adds the extra
code in an extension to the standard ns8250 probe routine, and the
rest of the driver is just the standard ns8250 code.
device compatible with multiple drivers matches the more specific driver
first and doesn't overwrite it later with the more generic. Move the
generic ns16550 to the end of the list.
1. Common headers for fdt.h and ofw_machdep.h under x86/include
with indirections under i386/include and amd64/include.
2. New modinfo for loader provided FDT blob.
3. Common x86_init_fdt() called from hammer_time() on amd64 and
init386() on i386.
4. Split-off FDT specific low-level console functions from FDT
bus methods for the uart(4) driver. The low-level console
logic has been moved to uart_cpu_fdt.c and is used for arm,
mips & powerpc only. The FDT bus methods are shared across
all architectures.
5. Add dev/fdt/fdt_x86.c to hold the fdt_fixup_table[] and the
fdt_pic_table[] arrays. Both are empty right now.
FDT addresses are I/O ports on x86. Since the core FDT code does
not handle different address spaces, adding support for both I/O
ports and memory addresses requires some thought and discussion.
It may be better to use a compile-time option that controls this.
Obtained from: Juniper Networks, Inc.
