alpha: Notice if we're being run under QEMU

When building a generic kernel, do a run-time check on the serial
number, like we do for MILO.  When building a custom kernel, make
this a configure-time check.

Signed-off-by: Richard Henderson <rth@twiddle.net>

1 files changed, 14 insertions, 0 deletions

diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig
index 135c674eaf9e..51cc8c353164 100644
--- a/arch/alpha/Kconfig
+++ b/arch/alpha/Kconfig
@@ -488,6 +488,20 @@ config VGA_HOSE
           which always have multiple hoses, and whose consoles support it.
 
 
+config ALPHA_QEMU
+        bool "Run under QEMU emulation"
+        depends on !ALPHA_GENERIC
+        ---help---
+          Assume the presence of special features supported by QEMU PALcode
+          that reduce the overhead of system emulation.
+
+          Generic kernels will auto-detect QEMU.  But when building a
+          system-specific kernel, the assumption is that we want to
+          elimiate as many runtime tests as possible.
+
+          If unsure, say N.
+
+
 config ALPHA_SRM
         bool "Use SRM as bootloader" if ALPHA_CABRIOLET || ALPHA_AVANTI_CH || ALPHA_EB64P || ALPHA_PC164 || ALPHA_TAKARA || ALPHA_EB164 || ALPHA_ALCOR || ALPHA_MIATA || ALPHA_LX164 || ALPHA_SX164 || ALPHA_NAUTILUS || ALPHA_NONAME
         depends on TTY