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path: root/payloads/libpayload/drivers/cbmem_console.c
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2017-07-13Rename __attribute__((packed)) --> __packedStefan Reinauer
Also unify __attribute__ ((..)) to __attribute__((..)) and handle ((__packed__)) like ((packed)) Change-Id: Ie60a51c3fa92b5009724a5b7c2932e361bf3490c Signed-off-by: Stefan Reinauer <stefan.reinauer@coreboot.org> Reviewed-on: https://review.coreboot.org/15921 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2017-04-20Turn CBMEM console into a ring buffer that can persist across rebootsJulius Werner
This patch allows the CBMEM console to persist across reboots, which should greatly help post factum debugging of issues involving multiple reboots. In order to prevent the console from filling up, it will instead operate as a ring buffer that continues to evict the oldest lines once full. (This means that if even a single boot doesn't fit into the buffer, we will now drop the oldest lines whereas previous code would've dropped the newest lines instead.) The console control structure is modified in a sorta backwards-compatible way, so that new readers can continue to work with old console buffers and vice versa. When an old reader reads a new buffer that has already once overflowed (i.e. is operating in true ring buffer mode) it will print lines out of order, but it will at least still print out the whole console content and not do any illegal memory accesses (assuming it correctly implemented cursor overflow as it was already possible before this patch). BUG=chromium:651966 TEST=Rebooted and confirmed output repeatedly on a Kevin and a Falco. Also confirmed correct behavior across suspend/resume for the latter. Change-Id: Ifcbf59d58e1ad20995b98d111c4647281fbb45ff Signed-off-by: Julius Werner <jwerner@chromium.org> Reviewed-on: https://review.coreboot.org/18301 Tested-by: build bot (Jenkins) Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2014-12-22libpayload: console: Allow output drivers to print whole strings at onceJulius Werner
The console output driver framework in libpayload is currently built on the putchar primitive, meaning that every driver's function gets called one character at a time. This becomes an issue when we add drivers that could output multiple characters at a time, but have a high constant overhead per invocation (such as the planned GDB stub, which needs to wrap a special frame around output strings and wait for an acknowledgement from the server). This patch adds a new 'write' function pointer to the console_output_driver structure as an alternative to 'putchar'. Output drivers need to provide at least one of the two ('write' is preferred if available). The CBMEM console driver is ported as a proof of concept (since it's our most performace-critical driver and should in theory benefit the most from less function pointer invocations, although it's probably still negligible compared to the big sprawling mess that is printf()). Even with this fix, the problem remains that printf() was written with the putchar primitive in mind. Even though normal text already contains an optimization to allow multiple characters at a time, almost all formatting directives cause their output (including things like padding whitespace) to be putchar()ed one character at a time. Therefore, this patch reworks parts of the output code (especially number printing) to all but remove that inefficiency (directives still invoke an extra write() call, but at least not one per character). Since I'm touching printf() core code anyway, I also tried to salvage what I could from that weird, broken "return negative on error" code path (not that any of our current output drivers can trigger it anyway). A final consequence of this patch is that the responsibility to prepend line feeds with carriage returns is moved into the output driver implementations. Doing this only makes sense for drivers with explicit cursor position control (i.e. serial or video), and things like the CBMEM console that appears like a normal file to the system really have no business containing carriage returns (we don't want people to accidentally associate us with Windows, now, do we?). BUG=chrome-os-partner:18390 TEST=Made sure video and CBMEM console still look good, tried printf() with as many weird edge-case strings as I could find and compared serial output as well as sprintf() return value. Original-Change-Id: Ie05ae489332a0103461620f5348774b6d4afd91a Original-Signed-off-by: Julius Werner <jwerner@chromium.org> Original-Reviewed-on: https://chromium-review.googlesource.com/196384 Original-Reviewed-by: Hung-Te Lin <hungte@chromium.org> Original-Reviewed-by: David Hendricks <dhendrix@chromium.org> (cherry picked from commit ab1ef0c07736fe1aa3e0baaf02d258731e6856c0) Signed-off-by: Marc Jones <marc.jones@se-eng.com> Change-Id: I78f5aedf6d0c3665924995cdab691ee0162de404 Reviewed-on: http://review.coreboot.org/7880 Tested-by: build bot (Jenkins) Reviewed-by: Patrick Georgi <pgeorgi@google.com>
2013-02-20libpayload: Fix license headersStefan Reinauer
Not only were these files checked in with the Chromium OS Authors copyright, but in addition they were wrongly licensed as GPL. Switch to 3-clause BSD (and, since we're changing it, fix copyright, too) Change-Id: I3656c1f4304d53e343d89bb7c909fd4b929249f4 Signed-off-by: Stefan Reinauer <reinauer@google.com> Reviewed-on: http://review.coreboot.org/2456 Tested-by: build bot (Jenkins) Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
2012-11-09libpayload: Add support for the CBMEM in memory console.Gabe Black
Change-Id: I1489b5306ef1ca078686fed4dba2d242f70ad941 Signed-off-by: Gabe Black <gabeblack@google.com> Reviewed-on: http://review.coreboot.org/1727 Tested-by: build bot (Jenkins) Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>