| /* |
| * Coherency fabric: low level functions |
| * |
| * Copyright (C) 2012 Marvell |
| * |
| * Gregory CLEMENT <gregory.clement@free-electrons.com> |
| * |
| * This file is licensed under the terms of the GNU General Public |
| * License version 2. This program is licensed "as is" without any |
| * warranty of any kind, whether express or implied. |
| * |
| * This file implements the assembly function to add a CPU to the |
| * coherency fabric. This function is called by each of the secondary |
| * CPUs during their early boot in an SMP kernel, this why this |
| * function have to callable from assembly. It can also be called by a |
| * primary CPU from C code during its boot. |
| */ |
| |
| #include <linux/linkage.h> |
| #define ARMADA_XP_CFB_CTL_REG_OFFSET 0x0 |
| #define ARMADA_XP_CFB_CFG_REG_OFFSET 0x4 |
| |
| .text |
| /* |
| * r0: Coherency fabric base register address |
| * r1: HW CPU id |
| */ |
| ENTRY(ll_set_cpu_coherent) |
| /* Create bit by cpu index */ |
| mov r3, #(1 << 24) |
| lsl r1, r3, r1 |
| |
| /* Add CPU to SMP group - Atomic */ |
| add r3, r0, #ARMADA_XP_CFB_CTL_REG_OFFSET |
| 1: |
| ldrex r2, [r3] |
| orr r2, r2, r1 |
| strex r0, r2, [r3] |
| cmp r0, #0 |
| bne 1b |
| |
| /* Enable coherency on CPU - Atomic */ |
| add r3, r3, #ARMADA_XP_CFB_CFG_REG_OFFSET |
| 1: |
| ldrex r2, [r3] |
| orr r2, r2, r1 |
| strex r0, r2, [r3] |
| cmp r0, #0 |
| bne 1b |
| |
| dsb |
| |
| mov r0, #0 |
| mov pc, lr |
| ENDPROC(ll_set_cpu_coherent) |