From 009f13159bfdccd6e06fe3b62a39fee6dce26c39 Mon Sep 17 00:00:00 2001 From: Gregory CLEMENT Date: Thu, 2 Aug 2012 11:16:29 +0300 Subject: arm: mvebu: Add support for coherency fabric in mach-mvebu The Armada 370 and Armada XP SOCs have a coherency fabric unit which is responsible for ensuring hardware coherency between all CPUs and between CPUs and I/O masters. This patch provides the basic support needed for SMP. Signed-off-by: Yehuda Yitschak Signed-off-by: Gregory CLEMENT Reviewed-by: Will Deacon --- arch/arm/mach-mvebu/coherency_ll.S | 49 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 arch/arm/mach-mvebu/coherency_ll.S (limited to 'arch/arm/mach-mvebu/coherency_ll.S') diff --git a/arch/arm/mach-mvebu/coherency_ll.S b/arch/arm/mach-mvebu/coherency_ll.S new file mode 100644 index 000000000000..53e8391192cd --- /dev/null +++ b/arch/arm/mach-mvebu/coherency_ll.S @@ -0,0 +1,49 @@ +/* + * Coherency fabric: low level functions + * + * Copyright (C) 2012 Marvell + * + * Gregory CLEMENT + * + * 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 +#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 + ldr r2, [r3] + orr r2, r2, r1 + str r2, [r3] + + /* Enable coherency on CPU - Atomic */ + add r3, r0, #ARMADA_XP_CFB_CFG_REG_OFFSET + ldr r2, [r3] + orr r2, r2, r1 + str r2, [r3] + + dsb + + mov r0, #0 + mov pc, lr +ENDPROC(ll_set_cpu_coherent) -- cgit v1.2.3