linux.git/drivers/tty/serial/earlycon.c, branch v6.1 Linux kernel source tree tty: move from strlcpy with unused retval to strscpy 2022-08-30T12:21:59+00:00 Wolfram Sang wsa+renesas@sang-engineering.com 2022-08-18T21:01:12+00:00 eb9e109d010cb79ab01d8562e851d53bcecf059b Follow the advice of the below link and prefer 'strscpy' in this subsystem. Conversion is 1:1 because the return value is not used. Generated by a coccinelle script. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Link: https://lore.kernel.org/r/20220818210113.7469-1-wsa+renesas@sang-engineering.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Follow the advice of the below link and prefer 'strscpy' in this
subsystem. Conversion is 1:1 because the return value is not used.
Generated by a coccinelle script.

Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Link: https://lore.kernel.org/r/20220818210113.7469-1-wsa+renesas@sang-engineering.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
earlycon: prevent multiple register_console() 2022-06-30T15:10:11+00:00 Michael Walle michael@walle.cc 2022-06-28T12:07:05+00:00 65e20e8cbbccaf0968474d27420c3a5170a5a5b8 If the earlycon parameter is given twice, the kernel will spit out a WARN() in register_console() because it was already registered. The non-dt variant setup_earlycon() already handles that gracefully. The dt variant of_setup_earlycon() doesn't. Add the check there and add the -EALREADY handling in early_init_dt_scan_chosen_stdout(). FWIW, this doesn't happen if CONFIG_ACPI_SPCR_TABLE is set. In that case the registration is delayed until after earlycon parameter(s) are parsed. Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Michael Walle <michael@walle.cc> Link: https://lore.kernel.org/r/20220628120705.200617-1-michael@walle.cc Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
If the earlycon parameter is given twice, the kernel will spit out a
WARN() in register_console() because it was already registered. The
non-dt variant setup_earlycon() already handles that gracefully. The dt
variant of_setup_earlycon() doesn't. Add the check there and add the
-EALREADY handling in early_init_dt_scan_chosen_stdout().

FWIW, this doesn't happen if CONFIG_ACPI_SPCR_TABLE is set. In that case
the registration is delayed until after earlycon parameter(s) are
parsed.

Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20220628120705.200617-1-michael@walle.cc
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
earlycon: simplify earlycon-table implementation 2020-12-04T14:49:48+00:00 Johan Hovold johan@kernel.org 2020-11-23T10:23:13+00:00 62dcd9c59f324e484c1d655884e0101a988f6671 Instead of using the array-of-pointers trick to avoid having gcc mess up the earlycon array stride, specify type alignment when declaring entries to prevent gcc from increasing alignment. This is essentially an alternative (one-line) fix to the problem addressed by commit dd709e72cb93 ("earlycon: Use a pointer table to fix __earlycon_table stride"). gcc can increase the alignment of larger objects with static extent as an optimisation, but this can be suppressed by using the aligned attribute when declaring variables. Note that we have been relying on this behaviour for kernel parameters for 16 years and it indeed hasn't changed since the introduction of the aligned attribute in gcc-3.1. Signed-off-by: Johan Hovold <johan@kernel.org> Link: https://lore.kernel.org/r/20201123102319.8090-3-johan@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Instead of using the array-of-pointers trick to avoid having gcc mess up
the earlycon array stride, specify type alignment when declaring entries
to prevent gcc from increasing alignment.

This is essentially an alternative (one-line) fix to the problem
addressed by commit dd709e72cb93 ("earlycon: Use a pointer table to fix
__earlycon_table stride").

gcc can increase the alignment of larger objects with static extent as
an optimisation, but this can be suppressed by using the aligned
attribute when declaring variables.

Note that we have been relying on this behaviour for kernel parameters
for 16 years and it indeed hasn't changed since the introduction of the
aligned attribute in gcc-3.1.

Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20201123102319.8090-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tty: serial: print earlycon info after match->setup 2020-09-16T11:16:20+00:00 Hsin-Yi Wang hsinyi@chromium.org 2020-09-15T05:48:25+00:00 f28295cc8ce14b7a78bc3900eaba2e6c34111595 8250 devices may modify iotype in their own earlycon setup. For example: 8250_mtk and 8250_uniphier force iotype to be MMIO32. Print earlycon info after match->setup to reflect actual earlycon info. Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org> Link: https://lore.kernel.org/r/20200915054825.3289105-1-hsinyi@chromium.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
8250 devices may modify iotype in their own earlycon setup. For example:
8250_mtk and 8250_uniphier force iotype to be MMIO32. Print earlycon info
after match->setup to reflect actual earlycon info.

Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
Link: https://lore.kernel.org/r/20200915054825.3289105-1-hsinyi@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: earlycon: prefer EARLYCON_DECLARE() variant 2020-03-07T08:52:01+00:00 Michael Walle michael@walle.cc 2020-02-20T17:46:07+00:00 f8c3686c65f099f0915bbf96885765594d675d5b If a driver exposes early consoles with EARLYCON_DECLARE() and OF_EARLYCON_DECLARE(), pefer the non-OF variant if the user specifies it by earlycon=<driver>,<options> The rationale behind this is that some drivers register multiple setup functions under the same driver name. Eg. OF_EARLYCON_DECLARE(lpuart, "fsl,vf610-lpuart", lpuart_early_console_setup); OF_EARLYCON_DECLARE(lpuart32, "fsl,ls1021a-lpuart", lpuart32_early_console_setup); OF_EARLYCON_DECLARE(lpuart32, "fsl,imx7ulp-lpuart", lpuart32_imx_early_console_setup); EARLYCON_DECLARE(lpuart, lpuart_early_console_setup); EARLYCON_DECLARE(lpuart32, lpuart32_early_console_setup); It depends on the order of the entries which console_setup() actually gets called. To make things worse, I guess it also depends on the compiler how these are ordered. Thus always prefer the EARLYCON_DECLARE() ones. Signed-off-by: Michael Walle <michael@walle.cc> Link: https://lore.kernel.org/r/20200220174607.24285-1-michael@walle.cc Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
If a driver exposes early consoles with EARLYCON_DECLARE() and
OF_EARLYCON_DECLARE(), pefer the non-OF variant if the user specifies it
by
  earlycon=<driver>,<options>

The rationale behind this is that some drivers register multiple setup
functions under the same driver name. Eg.

OF_EARLYCON_DECLARE(lpuart, "fsl,vf610-lpuart", lpuart_early_console_setup);
OF_EARLYCON_DECLARE(lpuart32, "fsl,ls1021a-lpuart", lpuart32_early_console_setup);
OF_EARLYCON_DECLARE(lpuart32, "fsl,imx7ulp-lpuart", lpuart32_imx_early_console_setup);
EARLYCON_DECLARE(lpuart, lpuart_early_console_setup);
EARLYCON_DECLARE(lpuart32, lpuart32_early_console_setup);

It depends on the order of the entries which console_setup() actually
gets called. To make things worse, I guess it also depends on the
compiler how these are ordered. Thus always prefer the EARLYCON_DECLARE()
ones.

Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200220174607.24285-1-michael@walle.cc
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
earlycon: Remove hardcoded port->uartclk initialization in of_setup_earlycon 2018-05-14T11:41:05+00:00 Michal Simek michal.simek@xilinx.com 2018-04-25T13:48:42+00:00 182ead3e418a20328b73152b8e81fc8b4cac3b0b There is no reason to initialize uartclk to BASE_BAUD * 16 for DT based systems. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Tested-by: Matt Redfearn <matt.redfearn@mips.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
There is no reason to initialize uartclk to BASE_BAUD * 16 for DT based
systems.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Tested-by: Matt Redfearn <matt.redfearn@mips.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Merge 4.17-rc3 into tty-next 2018-04-30T12:14:55+00:00 Greg Kroah-Hartman gregkh@linuxfoundation.org 2018-04-30T12:14:55+00:00 7b6c81f46c5dd7af316bf09aa1991ceed7e53dcd We want the tty and serial driver fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
We want the tty and serial driver fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
earlycon: Initialize port->uartclk based on clock-frequency property 2018-04-23T08:14:57+00:00 Michal Simek michal.simek@xilinx.com 2018-04-10T13:32:28+00:00 814453adea7d081ad8917aa0f32d6a14165a3563 On DT based platforms when current-speed property is present baudrate is setup. Also port->uartclk is initialized to bogus BASE_BAUD * 16 value. Drivers like uartps/ns16550 contain logic when baudrate and uartclk is used for baudrate calculation. The patch is reading optional clock-frequency property to replace bogus BASE_BAUD * 16 calculation to have proper baudrate calculation. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
On DT based platforms when current-speed property is present baudrate
is setup. Also port->uartclk is initialized to bogus BASE_BAUD * 16
value. Drivers like uartps/ns16550 contain logic when baudrate and
uartclk is used for baudrate calculation.

The patch is reading optional clock-frequency property to replace bogus
BASE_BAUD * 16 calculation to have proper baudrate calculation.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
earlycon: Use a pointer table to fix __earlycon_table stride 2018-04-23T08:06:59+00:00 Daniel Kurtz djkurtz@chromium.org 2018-04-06T23:21:53+00:00 dd709e72cb934eefd44de8d9969097173fbf45dc 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 <djkurtz@chromium.org> Suggested-by: Aaron Durbin <adurbin@chromium.org> Reviewed-by: Rob Herring <robh@kernel.org> Tested-by: Guenter Roeck <groeck@chromium.org> Reviewed-by: Guenter Roeck <groeck@chromium.org> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
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 <djkurtz@chromium.org>
Suggested-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Tested-by: Guenter Roeck <groeck@chromium.org>
Reviewed-by: Guenter Roeck <groeck@chromium.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
earlycon: add reg-offset to physical address before mapping 2018-02-28T12:48:21+00:00 Greentime Hu green.hu@gmail.com 2018-02-13T09:09:08+00:00 1f66dd36bb18437397ea0d7882c52f7e3c476e15 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 <greentime@andestech.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: stable@vger.kernel.org Fixes: 088da2a17619 ("of: earlycon: Initialize port fields from DT properties") Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
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 <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: stable@vger.kernel.org
Fixes: 088da2a17619 ("of: earlycon: Initialize port fields from DT properties")
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>