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2018-02-22metag: Remove arch/metag/James Hogan
The earliest Meta architecture port of Linux I have a record of was an import of a Meta port of Linux v2.4.1 in February 2004, which was worked on significantly over the next few years by Graham Whaley, Will Newton, Matt Fleming, myself and others. Eventually the port was merged into mainline in v3.9 in March 2013, not long after Imagination Technologies bought MIPS Technologies and shifted its CPU focus over to the MIPS architecture. As a result, though the port was maintained for a while, kept on life support for a while longer, and useful for testing a few specific drivers for which I don't have ready access to the equivalent MIPS hardware, it is now essentially dead with no users. It is also stuck using an out-of-tree toolchain based on GCC 4.2.4 which is no longer maintained, now struggles to build modern kernels due to toolchain bugs, and doesn't itself build with a modern GCC. The latest buildroot port is still using an old uClibc snapshot which is no longer served, and the latest uClibc doesn't build with GCC 4.2.4. So lets call it a day and drop the Meta architecture port from the kernel. RIP Meta. Signed-off-by: James Hogan <jhogan@kernel.org> Link: https://lkml.kernel.org/r/95906b76-6ce1-3f84-eaba-c29b4ae952eb@roeck-us.net Reviewed-by: Guenter Roeck <linux@roeck-us.net> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Graham Whaley <graham.whaley@gmail.com> Cc: linux-metag@vger.kernel.org
2013-07-02metag: kick: add missing irq_enter/exit to kick_handler()James Hogan
kick_handler() doesn't have an irq_enter/exit pair, but it's used for handling SMP IPIs which require work to be done in softirqs, which are invoked from irq_exit() when the hard irq nest count reaches 0. The scheduler_ipi() callback in the IPI handler calls irq_enter/exit itself, but this is inside kick_handler()'s spin lock critical section, so if an invoked softirq issues an IPI the kick_handler() will be re-entered on the same CPU and will deadlock. This is easily fixed by adding the missing irq_enter/exit to kick_handler() so that the hard irq nest count doesn't reach 0 until after the spin lock has been released. Ideally the spin lock protected handler list will also be replaced by a lockless RCU protected list since it is certainly mostly read. That can be done in a later change though. Signed-off-by: James Hogan <james.hogan@imgtec.com> Acked-by: Thomas Gleixner <tglx@linutronix.de>
2013-03-02metag: move kick.c exports out of metag_ksyms.cJames Hogan
It's less error prone to have function symbols exported immediately after the function rather than in metag_ksyms.c. Move each EXPORT_SYMBOL in metag_ksyms.c for symbols defined in kick.c into kick.c Signed-off-by: James Hogan <james.hogan@imgtec.com>
2013-03-02metag: TrapsJames Hogan
Add trap code for metag. At the lowest level Meta traps (and return from interrupt instruction - RTI) simply swap the PC and PCX registers and optionally toggle the interrupt status bit (ISTAT). Low level TBX code in tbipcx.S handles the core context save, determine the TBX signal number based on the core trigger that fired (using the TXSTATI status register), and call TBX signal handlers (mostly in traps.c) via a vector table. Signed-off-by: James Hogan <james.hogan@imgtec.com> Cc: Al Viro <viro@zeniv.linux.org.uk>