kernel/linux.git/drivers/tty/serial/earlycon.c, branch v4.9.331

earlycon: Use a pointer table to fix __earlycon_table stride

2018-05-01T22:13:09+00:00

commit dd709e72cb934eefd44de8d9969097173fbf45dc upstream. Commit 99492c39f39f ("earlycon: Fix __earlycon_table stride") tried to fix __earlycon_table stride by forcing the earlycon_id struct alignment to 32 and asking the linker to 32-byte align the __earlycon_table symbol. This fix was based on commit 07fca0e57fca92 ("tracing: Properly align linker defined symbols") which tried a similar fix for the tracing subsystem. However, this fix doesn't quite work because there is no guarantee that gcc will place structures packed into an array format. In fact, gcc 4.9 chooses to 64-byte align these structs by inserting additional padding between the entries because it has no clue that they are supposed to be in an array. If we are unlucky, the linker will assign symbol "__earlycon_table" to a 32-byte aligned address which does not correspond to the 64-byte aligned contents of section "__earlycon_table". To address this same problem, the fix to the tracing system was subsequently re-implemented using a more robust table of pointers approach by commits: 3d56e331b653 ("tracing: Replace syscall_meta_data struct array with pointer array") 654986462939 ("tracepoints: Fix section alignment using pointer array") e4a9ea5ee7c8 ("tracing: Replace trace_event struct array with pointer array") Let's use this same "array of pointers to structs" approach for EARLYCON_TABLE. Fixes: 99492c39f39f ("earlycon: Fix __earlycon_table stride") Signed-off-by: Daniel Kurtz Suggested-by: Aaron Durbin Reviewed-by: Rob Herring Tested-by: Guenter Roeck Reviewed-by: Guenter Roeck Cc: stable Signed-off-by: Greg Kroah-Hartman

earlycon: add reg-offset to physical address before mapping

2018-03-18T10:18:56+00:00

commit 1f66dd36bb18437397ea0d7882c52f7e3c476e15 upstream. It will get the wrong virtual address because port->mapbase is not added the correct reg-offset yet. We have to update it before earlycon_map() is called Signed-off-by: Greentime Hu Acked-by: Arnd Bergmann Cc: Peter Hurley Cc: stable@vger.kernel.org Fixes: 088da2a17619 ("of: earlycon: Initialize port fields from DT properties") Acked-by: Rob Herring Signed-off-by: Greg Kroah-Hartman

ACPI: parse SPCR and enable matching console

2016-09-28T15:46:46+00:00

'ARM Server Base Boot Requiremets' [1] mentions SPCR (Serial Port Console Redirection Table) [2] as a mandatory ACPI table that specifies the configuration of serial console. Defer initialization of DT earlycon until ACPI/DT decision is made. Parse the ACPI SPCR table, setup earlycon if required, enable specified console. Thanks to Peter Hurley for explaining how this should work. [1] http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.den0044a/index.html [2] https://msdn.microsoft.com/en-us/library/windows/hardware/dn639132(v=vs.85).aspx Signed-off-by: Aleksey Makarov Acked-by: Rafael J. Wysocki Reviewed-by: Peter Hurley Tested-by: Kefeng Wang Tested-by: Christopher Covington Signed-off-by: Greg Kroah-Hartman

of/serial: move earlycon early_param handling to serial

2016-09-28T15:43:15+00:00

We have multiple "earlycon" early_param handlers - merge the DT one into the main earlycon one. It's a cleanup that also will be useful to defer setting up DT console until ACPI/DT decision is made. Rename the exported function to avoid clashing with the function from arch/microblaze/kernel/prom.c Signed-off-by: Leif Lindholm Signed-off-by: Aleksey Makarov Acked-by: Rob Herring Acked-by: Greg Kroah-Hartman Reviewed-by: Peter Hurley Tested-by: Kefeng Wang Tested-by: Christopher Covington Signed-off-by: Greg Kroah-Hartman

serial: earlycon: Extend earlycon command line option to support 64-bit addresses

2016-09-02T13:03:35+00:00

earlycon implementation used "unsigned long" internally, but there are systems (ARM with LPAE) where sizeof(unsigned long) == 4 and uart is mapped beyond 4GiB address range. Switch to resource_size_t internally and replace obsoleted simple_strtoul() with kstrtoull(). Signed-off-by: Alexander Sverdlin Signed-off-by: Greg Kroah-Hartman

serial: earlycon: Show the earlycon "driver" in banner

2016-02-07T06:07:37+00:00

Output the earlycon "driver" from the just-parsed console 'name' and 'index' fields. NB: ->mapbase is a resource_size_t so use %pa format specifier Acked-by: Rob Herring Signed-off-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman

serial: earlycon: Common log banner for command line and DT

2016-02-07T06:07:37+00:00

Refactor the command line earlycon banner into earlycon_init() so both earlycon startup methods output an info banner. Acked-by: Rob Herring Signed-off-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman

of: earlycon: Move address translation to of_setup_earlycon()

2016-02-07T06:07:37+00:00

Cleanup the early DT/earlycon separation; remove the 'addr' parameter from of_setup_earlycon() and get the uart phys addr directly with a new wrapper function, of_flat_dt_translate_addr(). Limit fdt_translate_address() to file scope. Acked-by: Rob Herring Signed-off-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman

of: earlycon: Initialize port fields from DT properties

2016-02-07T06:07:37+00:00

Read the optional "reg-offset", "reg-shift", "reg-io-width" and endianness properties and initialize the respective struct uart_port field if found. NB: These bindings are common to several drivers and the values merely indicate the default value; the registering earlycon setup() method can simply override the values if required. Acked-by: Rob Herring Signed-off-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman

of: earlycon: Add options string handling

2016-02-07T06:07:37+00:00

Pass-through any options string in the 'stdout-path' property to the earlycon "driver" setup. Acked-by: Rob Herring Signed-off-by: Peter Hurley Signed-off-by: Greg Kroah-Hartman