This patchset makes it possible to use kgdb's NMI infrastructure on ARM platforms.
The patches have been previously circulated as part of a large patchset mixing together ARM architecture code and driver changes (http://thread.gmane.org/gmane.linux.ports.arm.kernel/333901 ). This patchset is dramatically cut down to include only the arch/arm code. The driver code (irqchip and tty/serial) will follow when/if the arch code is accepted.
The first two patches modify the FIQ infrastructure to allow interrupt controller drivers to register callbacks (the fiq_chip structure) to manage FIQ routings and to ACK and EOI the FIQ. This makes it possible to use FIQ in multi-platform kernels and with recent ARM interrupt controllers.
The remaining two patches provide architecture support for KGDB's NMI feature (and rely upon the preceding changes to the FIQ code).
Tested on qemu (versatile), STiH416 (B2020 board) and Freescale i.MX6 quad (wandboard).
Changes since v7:
- Introduced ack_fiq() to complement eoi_fiq(). Without this it is not possible to meet the GIC specification (previous versions worked when tested but are unpredictable according to the specification). ack_fiq() also makes is possible for drivers for devices with multiple interrupt lines to discover the interrupt source correctly.
Changes since v6:
- Corrected off-by-one comparison in has_fiq() (Nicolas Pitre) - Rewrote the FIQ stack initialization (Nicolas Pitre). This fixes a serious data corruption bug due to bad stack mismanagement. - Introduced __fiq_abt to ensure lr_abt and spsr_abt are saved and restored if we fast-interrupt an abort (Russell King). - Significantly improved the commenting of the exception handlers. - Added a call to trace_hardirqs_on() if we clear the I bit as we exit the exception handler.
Changes since v5:
- Separated anything not strictly impacting arch/arm. - Fixed a spurious add/remove of code within the series (there was broken code in intermediate patches)
For previous changes see: http://thread.gmane.org/gmane.linux.ports.arm.kernel/333901
Anton Vorontsov (2): ARM: Move some macros from entry-armv to entry-header ARM: Add KGDB/KDB FIQ debugger generic code
Daniel Thompson (2): arm: fiq: Add callbacks to manage FIQ routings arm: fiq: Allow ACK and EOI to be passed to the intc
arch/arm/Kconfig | 2 + arch/arm/Kconfig.debug | 18 +++++ arch/arm/include/asm/fiq.h | 17 ++++ arch/arm/include/asm/kgdb.h | 7 ++ arch/arm/kernel/Makefile | 1 + arch/arm/kernel/entry-armv.S | 151 +---------------------------------- arch/arm/kernel/entry-header.S | 164 +++++++++++++++++++++++++++++++++++++++ arch/arm/kernel/fiq.c | 122 ++++++++++++++++++++++++++++- arch/arm/kernel/kgdb_fiq.c | 132 +++++++++++++++++++++++++++++++ arch/arm/kernel/kgdb_fiq_entry.S | 130 +++++++++++++++++++++++++++++++ 10 files changed, 592 insertions(+), 152 deletions(-) create mode 100644 arch/arm/kernel/kgdb_fiq.c create mode 100644 arch/arm/kernel/kgdb_fiq_entry.S
-- 1.9.3