Blackfin arch: allow people to select the feature that is unavailable to the kernel

[pandora-kernel.git] / arch / blackfin / Kconfig

diff --git a/arch/blackfin/Kconfig b/arch/blackfin/Kconfig
index cdce8cc..26ebb0e 100644 (file)
--- a/arch/blackfin/Kconfig
+++ b/arch/blackfin/Kconfig
@@ -521,6 +521,52 @@ config BFIN_IDLE_LED_NUM
        help
          Select the LED (marked on the board) for you to blink.
 
+choice
+       prompt "Blackfin Exception Scratch Register"
+       default BFIN_SCRATCH_REG_RETN
+       help
+         Select the resource to reserve for the Exception handler:
+           - RETN: Non-Maskable Interrupt (NMI)
+           - RETE: Exception Return (JTAG/ICE)
+           - CYCLES: Performance counter
+
+         If you are unsure, please select "RETN".
+
+config BFIN_SCRATCH_REG_RETN
+       bool "RETN"
+       help
+         Use the RETN register in the Blackfin exception handler
+         as a stack scratch register.  This means you cannot
+         safely use NMI on the Blackfin while running Linux, but
+         you can debug the system with a JTAG ICE and use the
+         CYCLES performance registers.
+
+         If you are unsure, please select "RETN".
+
+config BFIN_SCRATCH_REG_RETE
+       bool "RETE"
+       help
+         Use the RETE register in the Blackfin exception handler
+         as a stack scratch register.  This means you cannot
+         safely use a JTAG ICE while debugging a Blackfin board,
+         but you can safely use the CYCLES performance registers
+         and the NMI.
+
+         If you are unsure, please select "RETN".
+
+config BFIN_SCRATCH_REG_CYCLES
+       bool "CYCLES"
+       help
+         Use the CYCLES register in the Blackfin exception handler
+         as a stack scratch register.  This means you cannot
+         safely use the CYCLES performance registers on a Blackfin
+         board at anytime, but you can debug the system with a JTAG
+         ICE and use the NMI.
+
+         If you are unsure, please select "RETN".
+
+endchoice
+
 #
 # Sorry - but you need to put the hex address here -
 #