18c2ecf20Sopenharmony_ci/* SPDX-License-Identifier: GPL-2.0-or-later */
28c2ecf20Sopenharmony_ci/*
38c2ecf20Sopenharmony_ci * Basic assembly code to read BHRB entries
48c2ecf20Sopenharmony_ci *
58c2ecf20Sopenharmony_ci * Copyright 2013 Anshuman Khandual, IBM Corporation.
68c2ecf20Sopenharmony_ci */
78c2ecf20Sopenharmony_ci#include <asm/ppc_asm.h>
88c2ecf20Sopenharmony_ci#include <asm/ppc-opcode.h>
98c2ecf20Sopenharmony_ci
108c2ecf20Sopenharmony_ci	.text
118c2ecf20Sopenharmony_ci
128c2ecf20Sopenharmony_ci.balign 8
138c2ecf20Sopenharmony_ci
148c2ecf20Sopenharmony_ci/* r3 = n  (where n = [0-31])
158c2ecf20Sopenharmony_ci * The maximum number of BHRB entries supported with PPC_MFBHRBE instruction
168c2ecf20Sopenharmony_ci * is 1024. We have limited number of table entries here as POWER8 implements
178c2ecf20Sopenharmony_ci * 32 BHRB entries.
188c2ecf20Sopenharmony_ci */
198c2ecf20Sopenharmony_ci
208c2ecf20Sopenharmony_ci/* .global read_bhrb */
218c2ecf20Sopenharmony_ci_GLOBAL(read_bhrb)
228c2ecf20Sopenharmony_ci	cmpldi	r3,31
238c2ecf20Sopenharmony_ci	bgt	1f
248c2ecf20Sopenharmony_ci	ld	r4,bhrb_table@got(r2)
258c2ecf20Sopenharmony_ci	sldi	r3,r3,3
268c2ecf20Sopenharmony_ci	add	r3,r4,r3
278c2ecf20Sopenharmony_ci	mtctr	r3
288c2ecf20Sopenharmony_ci	bctr
298c2ecf20Sopenharmony_ci1:	li	r3,0
308c2ecf20Sopenharmony_ci	blr
318c2ecf20Sopenharmony_ci
328c2ecf20Sopenharmony_ci#define MFBHRB_TABLE1(n) PPC_MFBHRBE(R3,n); blr
338c2ecf20Sopenharmony_ci#define MFBHRB_TABLE2(n) MFBHRB_TABLE1(n); MFBHRB_TABLE1(n+1)
348c2ecf20Sopenharmony_ci#define MFBHRB_TABLE4(n) MFBHRB_TABLE2(n); MFBHRB_TABLE2(n+2)
358c2ecf20Sopenharmony_ci#define MFBHRB_TABLE8(n) MFBHRB_TABLE4(n); MFBHRB_TABLE4(n+4)
368c2ecf20Sopenharmony_ci#define MFBHRB_TABLE16(n) MFBHRB_TABLE8(n); MFBHRB_TABLE8(n+8)
378c2ecf20Sopenharmony_ci#define MFBHRB_TABLE32(n) MFBHRB_TABLE16(n); MFBHRB_TABLE16(n+16)
388c2ecf20Sopenharmony_ci
398c2ecf20Sopenharmony_cibhrb_table:
408c2ecf20Sopenharmony_ci	MFBHRB_TABLE32(0)
41