Commit 31ee4b2f authored by Martin Schwidefsky's avatar Martin Schwidefsky
Browse files

[S390] Calibrate delay and bogomips. 



Preset the bogomips number to the cpu capacity value reported by
store system information in SYSIB 1.2.2. This value is constant
for a particular machine model and can be used to determine
relative performance differences between machines.

Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent 31cb4bd3

arch/s390/Kconfig

+0 −4
Original line number Diff line number Diff line
@@ -34,10 +34,6 @@ config GENERIC_HWEIGHT 
	bool

	default y



config GENERIC_CALIBRATE_DELAY

	bool

	default y



config GENERIC_TIME

	def_bool y

arch/s390/kernel/setup.c

+1 −0
Original line number Diff line number Diff line
@@ -938,6 +938,7 @@ static int show_cpuinfo(struct seq_file *m, void *v) 
        struct cpuinfo_S390 *cpuinfo;

	unsigned long n = (unsigned long) v - 1;



	s390_adjust_jiffies();

	preempt_disable();

	if (!n) {

		seq_printf(m, "vendor_id       : IBM/S390\n"

arch/s390/lib/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -4,7 +4,7 @@ 


EXTRA_AFLAGS := -traditional



lib-y += delay.o string.o uaccess_std.o uaccess_pt.o

lib-y += delay.o string.o uaccess_std.o uaccess_pt.o qrnnd.o

lib-$(CONFIG_32BIT) += div64.o

lib-$(CONFIG_64BIT) += uaccess_mvcos.o

lib-$(CONFIG_SMP) += spinlock.o

arch/s390/lib/qrnnd.S

0 → 100644
+77 −0
Original line number Diff line number Diff line 
# S/390 __udiv_qrnnd



# r2 : &__r

# r3 : upper half of 64 bit word n

# r4 : lower half of 64 bit word n

# r5 : divisor d

# the reminder r of the division is to be stored to &__r and

# the quotient q is to be returned



	.text

	.globl __udiv_qrnnd

__udiv_qrnnd:

	st    %r2,24(%r15)	  # store pointer to reminder for later

	lr    %r0,%r3		  # reload n

	lr    %r1,%r4

	ltr   %r2,%r5		  # reload and test divisor

	jp    5f

	# divisor >= 0x80000000

	srdl  %r0,2		  # n/4

	srl   %r2,1		  # d/2

	slr   %r1,%r2		  # special case if last bit of d is set

	brc   3,0f		  #  (n/4) div (n/2) can overflow by 1

	ahi   %r0,-1		  #  trick: subtract n/2, then divide

0:	dr    %r0,%r2		  # signed division

	ahi   %r1,1		  #  trick part 2: add 1 to the quotient

	# now (n >> 2) = (d >> 1) * %r1 + %r0

	lhi   %r3,1

	nr    %r3,%r1		  # test last bit of q

	jz    1f

	alr   %r0,%r2		  # add (d>>1) to r

1:	srl   %r1,1		  # q >>= 1

	# now (n >> 2) = (d&-2) * %r1 + %r0

	lhi   %r3,1

	nr    %r3,%r5		  # test last bit of d

	jz    2f

	slr   %r0,%r1		  # r -= q

	brc   3,2f		  # borrow ?

	alr   %r0,%r5		  # r += d

	ahi   %r1,-1

2:	# now (n >> 2) = d * %r1 + %r0

	alr   %r1,%r1		  # q <<= 1

	alr   %r0,%r0		  # r <<= 1

	brc   12,3f		  # overflow on r ?

	slr   %r0,%r5		  # r -= d

	ahi   %r1,1		  # q += 1

3:	lhi   %r3,2

	nr    %r3,%r4		  # test next to last bit of n

	jz    4f

	ahi   %r0,1		  # r += 1

4:	clr   %r0,%r5		  # r >= d ?

	jl    6f

	slr   %r0,%r5		  # r -= d

	ahi   %r1,1		  # q += 1

	# now (n >> 1) = d * %r1 + %r0

	j     6f

5:	# divisor < 0x80000000

	srdl  %r0,1

	dr    %r0,%r2		  # signed division

	# now (n >> 1) = d * %r1 + %r0

6:	alr   %r1,%r1		  # q <<= 1

	alr   %r0,%r0		  # r <<= 1

	brc   12,7f		  # overflow on r ?

	slr   %r0,%r5		  # r -= d

	ahi   %r1,1		  # q += 1

7:	lhi   %r3,1

	nr    %r3,%r4		  # isolate last bit of n

	alr   %r0,%r3		  # r += (n & 1)

	clr   %r0,%r5		  # r >= d ?

	jl    8f

	slr   %r0,%r5		  # r -= d

	ahi   %r1,1		  # q += 1

8:	# now n = d * %r1 + %r0

	l     %r2,24(%r15)

	st    %r0,0(%r2)

	lr    %r2,%r1

	br    %r14

	.end	__udiv_qrnnd

arch/s390/math-emu/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -2,7 +2,7 @@ 
# Makefile for the FPU instruction emulation.

#



obj-$(CONFIG_MATHEMU) := math.o qrnnd.o

obj-$(CONFIG_MATHEMU) := math.o



EXTRA_CFLAGS := -I$(src) -Iinclude/math-emu -w

EXTRA_AFLAGS := -traditional