1. 08 Sep, 2010 2 commits
    • Will Deacon's avatar
      ARM: 6356/1: hw-breakpoint: add ARM backend for the hw-breakpoint framework · f81ef4a9
      Will Deacon authored
      The hw-breakpoint framework in the kernel requires architecture-specific
      support in order to install, remove, validate and manage hardware
      breakpoints.
      
      This patch adds initial support for this framework to the ARM architecture,
      but restricts the number of watchpoints to a single resource to get around
      the fact that the Data Fault Address Register is unknown when a watchpoint
      debug exception is taken.
      
      On cores with v7 debug, the Kernel can handle breakpoint and watchpoint
      exceptions occuring from userspace. Older cores require clients to handle
      the exception themselves by registering an appropriate overflow handler
      or, in the case of ptrace, handling the raised SIGTRAP.
      
      The memory-mapped extended debug interface is unsupported due to its
      unreliability in real implementations.
      
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: S. Karthikeyan <informkarthik@gmail.com>
      Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
      Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
      f81ef4a9
    • Will Deacon's avatar
      ARM: 6355/1: hw-breakpoint: add mechanism for hooking into prefetch aborts · 3a4b5dca
      Will Deacon authored
      On ARM processors with hardware breakpoint and watchpoint support,
      triggering these events results in a debug exception. These manifest
      as prefetch and data aborts respectively.
      
      arch/arm/mm/fault.c already provides hook_fault_code for hooking
      into data aborts dependent on the DFSR. This patch adds a new function,
      hook_ifault_code for hooking into prefetch aborts in the same manner.
      
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: S. Karthikeyan <informkarthik@gmail.com>
      Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
      Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
      3a4b5dca
  2. 07 Sep, 2010 38 commits