diff options
| author | Gregory CLEMENT <gregory.clement@free-electrons.com> | 2012-08-02 11:16:29 +0300 |
|---|---|---|
| committer | Gregory CLEMENT <gregory.clement@free-electrons.com> | 2012-11-21 16:49:06 +0100 |
| commit | 009f13159bfdccd6e06fe3b62a39fee6dce26c39 (patch) | |
| tree | 681d68bde140a819f18af537a51131c850dc8edb /arch/arm/mach-mvebu/coherency_ll.S | |
| parent | 1611f872513735ac7105535689c0dd668fbf1c04 (diff) | |
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 <yehuday@marvell.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Reviewed-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'arch/arm/mach-mvebu/coherency_ll.S')
| -rw-r--r-- | arch/arm/mach-mvebu/coherency_ll.S | 49 |
1 files changed, 49 insertions, 0 deletions
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 <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 + 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) |