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path: root/drivers/tty/serial/earlycon.c
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2016-09-28ACPI: parse SPCR and enable matching consoleAleksey Makarov1-2/+17
'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 <aleksey.makarov@linaro.org> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Tested-by: Kefeng Wang <wangkefeng.wang@huawei.com> Tested-by: Christopher Covington <cov@codeaurora.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-28of/serial: move earlycon early_param handling to serialLeif Lindholm1-1/+1
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 <leif.lindholm@linaro.org> Signed-off-by: Aleksey Makarov <aleksey.makarov@linaro.org> Acked-by: Rob Herring <robh@kernel.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Tested-by: Kefeng Wang <wangkefeng.wang@huawei.com> Tested-by: Christopher Covington <cov@codeaurora.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-02serial: earlycon: Extend earlycon command line option to support 64-bit ↵Alexander Sverdlin1-4/+3
addresses 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 <alexander.sverdlin@nokia.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07serial: earlycon: Show the earlycon "driver" in bannerPeter Hurley1-6/+6
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 <robh@kernel.org> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07serial: earlycon: Common log banner for command line and DTPeter Hurley1-13/+14
Refactor the command line earlycon banner into earlycon_init() so both earlycon startup methods output an info banner. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07of: earlycon: Move address translation to of_setup_earlycon()Peter Hurley1-3/+9
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 <robh@kernel.org> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07of: earlycon: Initialize port fields from DT propertiesPeter Hurley1-0/+31
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 <robh@kernel.org> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07of: earlycon: Add options string handlingPeter Hurley1-2/+7
Pass-through any options string in the 'stdout-path' property to the earlycon "driver" setup. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07of: earlycon: Fixup earlycon console name and indexPeter Hurley1-3/+3
Use the console name embedded in the OF earlycon table by the OF_EARLYCON_DECLARE() macro to initialize the struct console 'name' and 'index' fields. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07serial: earlycon: Fixup earlycon console name and indexPeter Hurley1-3/+22
Properly initialize the struct console 'name' and 'index' fields for the registering earlycon. For earlycons w/o trailing numerals, the index is set to 0; otherwise, the index is set to the value of the trailing numeral. For example, the 'exynos4210' earlycon name == "exynos" and index == 4210. Earlycons with embedded numerals will have all non-trailing numerals as part of the name; for example, the 's3c2412' earlycon name == "s3c" and index == 2412. This ackward scheme was initially added for the uart8250 earlycon; adopt this scheme for the other earlycon "drivers". Introduce earlycon_init() which performs the string scanning and initializes the name and index fields; encapsulate the other console field initializations within. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07earlycon: Use common framework for earlycon declarationsPeter Hurley1-9/+1
Use a single common table of struct earlycon_id for both command line and devicetree. Re-define OF_EARLYCON_DECLARE() macro to instance a unique earlycon declaration (the declaration is only guaranteed to be unique within a compilation unit; separate compilation units must still use unique earlycon names). The semantics of OF_EARLYCON_DECLARE() is different; it declares an earlycon which can matched either on the command line or by devicetree. EARLYCON_DECLARE() is semantically unchanged; it declares an earlycon which is matched by command line only. Remove redundant instances of EARLYCON_DECLARE(). This enables all earlycons to properly initialize struct console with the appropriate name and index, which improves diagnostics and enables direct earlycon-to-console handoff. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-07of: earlycon: of_setup_earlycon() requires CONFIG_OF_EARLY_FLATTREEPeter Hurley1-0/+4
DT earlycon is only supported for CONFIG_OF_EARLY_FLATTREE=y; exclude of_setup_earlycon() if not defined. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-21Merge 4.4-rc6 into tty-nextGreg Kroah-Hartman1-0/+2
We want the serial/tty fixes in here as well. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-14serial: support 16-bit register interface for consoleMasahiro Yamada1-4/+11
Currently, 8-bit (MMIO) and 32-bit (MMIO32) register interfaces are supported for the 8250 console, but the 16-bit (MMIO16) is not. The 8250 UART device on my board is connected to a 16-bit bus and my main motivation is to use earlycon with it. (Refer to arch/arm/boot/dts/uniphier-support-card.dtsi) Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-12-13serial: earlycon: Add missing spinlock initializationGeert Uytterhoeven1-0/+2
If an earlycon console driver needs to acquire the uart_port.lock spinlock for serial console output, and CONFIG_DEBUG_SPINLOCK=y: BUG: spinlock bad magic on CPU#0, swapper/0 lock: sci_ports+0x0/0x3480, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0 CPU: 0 PID: 0 Comm: swapper Not tainted 4.4.0-rc2-koelsch-g62ea5edf143bb1d0-dirty #2083 Hardware name: Generic R8A7791 (Flattened Device Tree) [<c00173a0>] (unwind_backtrace) from [<c0013094>] (show_stack+0x10/0x14) [<c0013094>] (show_stack) from [<c01f2338>] (dump_stack+0x70/0x8c) [<c01f2338>] (dump_stack) from [<c00702d8>] (do_raw_spin_lock+0x20/0x190) [<c00702d8>] (do_raw_spin_lock) from [<c0267590>] (serial_console_write+0x4c/0x130) [<c0267590>] (serial_console_write) from [<c00734c4>] (call_console_drivers.constprop.13+0xc8/0xec) [<c00734c4>] (call_console_drivers.constprop.13) from [<c0074ef0>] (console_unlock+0x354/0x440) [<c0074ef0>] (console_unlock) from [<c0075bb4>] (register_console+0x2a0/0x394) [<c0075bb4>] (register_console) from [<c06cb750>] (of_setup_earlycon+0x90/0xa4) [<c06cb750>] (of_setup_earlycon) from [<c06cfb60>] (setup_of_earlycon+0x118/0x13c) [<c06cfb60>] (setup_of_earlycon) from [<c06b34ac>] (do_early_param+0x64/0xb4) [<c06b34ac>] (do_early_param) from [<c00472c0>] (parse_args+0x254/0x350) [<c00472c0>] (parse_args) from [<c06b3860>] (parse_early_options+0x2c/0x3c) [<c06b3860>] (parse_early_options) from [<c06b389c>] (parse_early_param+0x2c/0x40) [<c06b389c>] (parse_early_param) from [<c06b5b08>] (setup_arch+0x520/0xaf0) [<c06b5b08>] (setup_arch) from [<c06b3948>] (start_kernel+0x94/0x370) [<c06b3948>] (start_kernel) from [<40008090>] (0x40008090) Initialize the spinlock in of_setup_earlycon() and register_earlycon(), to fix this for both DT-based and legacy earlycon. If the driver would reinitialize the spinlock again, this is harmless, as it's allowed to reinitialize an unlocked spinlock. Alternatives are: - Drivers having an early_serial_console_write() that only performs the core functionality of serial_console_write(), without acquiring the lock (which may be unsafe, depending on the hardware), - Drivers initializing the spinlock in their private earlycon setup functions. As uart_port is owned by generic serial_core, and uart_port.lock is initialized by uart_add_one_port() for the normal case, this can better be handled in the earlycon core. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Peter Hurley <peter@hurleysoftware.com> Reported-by: Bjorn Andersson <bjorn.andersson@sonymobile.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-06-01serial: earlycon: Add support for big-endian MMIO accessesNoam Camus1-3/+6
Support command line parameters of the form: earlycon=<name>,io|mmio|mmio32|mmio32be,<addr>,<options> This commit seem to be needed even after commit: serial: 8250: Add support for big-endian MMIO accesses c627f2ceb692e8a9358b64ac2d139314e7bb0d17 Signed-off-by: Noam Camus <noamc@ezchip.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-05-08earlycon: Revert log warningsPeter Hurley1-7/+2
Log warnings meant to help diagnose problems setting up earlycon are reporting false positives for 'console='. Revert to the previous behavior which reported nothing. Cc: Maciej W. Rozycki <macro@linux-mips.org> Cc: Robert Schwebel <r.schwebel@pengutronix.de> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-26serial: earlycon: Enable earlycon without command line paramPeter Hurley1-19/+73
Earlycon matching can only be triggered if 'earlycon=...' has been specified on the kernel command line. To workaround this limitation requires tight coupling between arches and specific serial drivers in order to start an earlycon. Devicetree avoids this limitation with a link table that contains the required data to match earlycons. Mirror this approach for earlycon match by name. Re-purpose EARLYCON_DECLARE to generate a table entry which associates name with setup() function. Re-purpose setup_earlycon() to scan this table for an earlycon match, which is registered if found. Declare one "earlycon" early_param, which calls setup_earlycon(). This design allows setup_earlycon() to be called directly with a param string (as if 'earlycon=...' had been set on the command line). Re-registration (either directly or by early_param) is prevented. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-26serial: earlycon: Refactor earlycon registrationPeter Hurley1-17/+25
Separate earlycon matching from registration; add register_earlycon which initializes and registers the matched earlycon. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-26serial: earlycon: Skip parse_options() if empty stringPeter Hurley1-4/+7
Earlycon param strings of the form earlycon=<name> are rejected from parse_options() with an error (which, in turn, results in a NULL argument for the setup() method options parameter). Only pass non-empty string to parse_options(); this will enable handling actual parse errors differently than expected and allow formats. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-26serial: earlycon: Ignore parse_options() error codePeter Hurley1-2/+1
Because setup_earlycon() continues to attempt console registration if an error occurred parsing the option string, the actual value of the error code from parse_options() is ignored. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-26serial: earlycon: Move ->uartclk initializePeter Hurley1-2/+1
Initializing the ->uartclk field is not related to option parsing; relocate from parse_options() to setup_earlycon() (which mirrors the behavior of of_setup_earlycon()). Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-03-07serial: earlycon: Refactor parse_options into serial corePeter Hurley1-26/+13
Prepare to support console-defined matching; refactor the command line parameter string processing from parse_options() into a new core function, uart_parse_earlycon(), which decodes command line parameters of the form: earlycon=<name>,io|mmio|mmio32,<addr>,<options> console=<name>,io|mmio|mmio32,<addr>,<options> earlycon=<name>,0x<addr>,<options> console=<name>,0x<addr>,<options> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-11-06tty/serial: earlycon: Fix print for implied MMIO caseKumar Gala1-1/+1
For the case in which we just provide an address as an argument to the earlycon console type like: earlycon=msm_serial_dm,0xf991e000 We would report this as an IO port based mapping and not as MMIO. Simple fix to use the port->iotype to decide which message to print. Signed-off-by: Kumar Gala <galak@codeaurora.org> Acked-by: Mark RUtland <mark.rutland@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-06-20tty/serial: fix 8250 early console option passing to regular consoleRob Herring1-1/+1
In the conversion to generic early console, the passing of options from the early 8250 console to the regular ttyS console was broken. This resulted in the baud rate changing when switching consoles during boot. This feature allows specifying a single console option on the kernel command line rather than both an early console and regular serial tty console. It would be nice to generalize this feature. However, it only works if the correct baud rate can be probed early which is not the case on many platforms which have non-standard UART clock rates. So for now, this is left as an 8250 specific feature. Reported-and-tested-by: Tony Luck <tony.luck@intel.com> Signed-off-by: Rob Herring <robh@kernel.org> Cc: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-05-21serial: earlycon: add DT supportRob Herring1-0/+28
This adds the infrastructure to generic earlycon for earlycon setup using DT. The actual setup is not enabled until a following commit to add the FDT parsing. Signed-off-by: Rob Herring <robh@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Arnd Bergmann <arnd@arndb.de> Acked-by: Grant Likely <grant.likely@linaro.org>
2014-05-04tty/serial: fix generic earlycon option parsingRob Herring1-13/+5
Commit 9aac5887595 (tty/serial: add generic serial earlycon) moved console option parsing from 8250_early.c and converted to kstrto* functions from simple_strtoul along the way. However, kstrto* functions are not equivalent in that they do not allow non-convertible characters at the end such as "115200n8". Fix this by changing back to simple_strtoul and ignore what checkpatch.pl says. Reported-by: Yinghai Lu <yinghai@kernel.org> Cc: Jiri Slaby <jslaby@suse.cz> Cc: linux-serial@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-04-25tty/serial: add generic serial earlyconRob Herring1-0/+152
This introduces generic earlycon infrastructure for serial devices based on the 8250 earlycon. This allows for supporting earlycon option with other serial devices. The earlycon output is enabled at the time early_params are processed. Only architectures that have fixmap support or have functional ioremap when early_params are processed are supported. This is the same restriction that the 8250 driver had. Signed-off-by: Rob Herring <robh@kernel.org> Cc: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>