Commit 994dcf70 authored by Richard Henderson's avatar Richard Henderson Committed by Matt Turner
Browse files

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: default avatarRichard Henderson <rth@twiddle.net>
parent a47e5bb5

arch/alpha/Kconfig

+14 −0
Original line number Diff line number Diff line
@@ -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

arch/alpha/include/asm/machvec.h

+12 −6
Original line number Diff line number Diff line
@@ -126,13 +126,19 @@ extern struct alpha_machine_vector alpha_mv; 


#ifdef CONFIG_ALPHA_GENERIC

extern int alpha_using_srm;

extern int alpha_using_qemu;

#else

# ifdef CONFIG_ALPHA_SRM

#  define alpha_using_srm 1

# else

#  define alpha_using_srm 0

# endif

# ifdef CONFIG_ALPHA_QEMU

#  define alpha_using_qemu 1

# else

#  define alpha_using_qemu 0

# endif

#endif /* GENERIC */



#endif

#endif /* __KERNEL__ */

#endif /* __ALPHA_MACHVEC_H */

arch/alpha/kernel/setup.c

+12 −1
Original line number Diff line number Diff line
@@ -115,10 +115,17 @@ unsigned long alpha_agpgart_size = DEFAULT_AGP_APER_SIZE; 


#ifdef CONFIG_ALPHA_GENERIC

struct alpha_machine_vector alpha_mv;

#endif



#ifndef alpha_using_srm

int alpha_using_srm;

EXPORT_SYMBOL(alpha_using_srm);

#endif



#ifndef alpha_using_qemu

int alpha_using_qemu;

#endif



static struct alpha_machine_vector *get_sysvec(unsigned long, unsigned long,

					       unsigned long);

static struct alpha_machine_vector *get_sysvec_byname(const char *);
@@ -529,11 +536,15 @@ setup_arch(char **cmdline_p) 
	atomic_notifier_chain_register(&panic_notifier_list,

			&alpha_panic_block);



#ifdef CONFIG_ALPHA_GENERIC

#ifndef alpha_using_srm

	/* Assume that we've booted from SRM if we haven't booted from MILO.

	   Detect the later by looking for "MILO" in the system serial nr.  */

	alpha_using_srm = strncmp((const char *)hwrpb->ssn, "MILO", 4) != 0;

#endif

#ifndef alpha_using_qemu

	/* Similarly, look for QEMU.  */

	alpha_using_qemu = strstr((const char *)hwrpb->ssn, "QEMU") != 0;

#endif



	/* If we are using SRM, we want to allow callbacks

	   as early as possible, so do this NOW, and then