linux/arch/powerpc/perf/bhrb.S
Nicholas Piggin dab3b8f4fd powerpc/64: asm use consistent global variable declaration and access
Use helper macros to access global variables, and place them in .data
sections rather than in .toc. Putting addresses in TOC is not required
because the kernel is linked with a single TOC.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220926034057.2360083-3-npiggin@gmail.com
2022-09-28 19:22:12 +10:00

41 lines
991 B
ArmAsm

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Basic assembly code to read BHRB entries
*
* Copyright 2013 Anshuman Khandual, IBM Corporation.
*/
#include <asm/ppc_asm.h>
#include <asm/ppc-opcode.h>
.text
.balign 8
/* r3 = n (where n = [0-31])
* The maximum number of BHRB entries supported with PPC_MFBHRBE instruction
* is 1024. We have limited number of table entries here as POWER8 implements
* 32 BHRB entries.
*/
/* .global read_bhrb */
_GLOBAL(read_bhrb)
cmpldi r3,31
bgt 1f
LOAD_REG_ADDR(r4, bhrb_table)
sldi r3,r3,3
add r3,r4,r3
mtctr r3
bctr
1: li r3,0
blr
#define MFBHRB_TABLE1(n) PPC_MFBHRBE(R3,n); blr
#define MFBHRB_TABLE2(n) MFBHRB_TABLE1(n); MFBHRB_TABLE1(n+1)
#define MFBHRB_TABLE4(n) MFBHRB_TABLE2(n); MFBHRB_TABLE2(n+2)
#define MFBHRB_TABLE8(n) MFBHRB_TABLE4(n); MFBHRB_TABLE4(n+4)
#define MFBHRB_TABLE16(n) MFBHRB_TABLE8(n); MFBHRB_TABLE8(n+8)
#define MFBHRB_TABLE32(n) MFBHRB_TABLE16(n); MFBHRB_TABLE16(n+16)
bhrb_table:
MFBHRB_TABLE32(0)