[PATCH V7 1/5] arm: mvebu: Add support for coherency fabric in mach-mvebu
Gregory CLEMENT
gregory.clement at free-electrons.com
Wed Nov 21 11:00:12 EST 2012
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 at marvell.com>
Signed-off-by: Gregory CLEMENT <gregory.clement at free-electrons.com>
Reviewed-by: Will Deacon <will.deacon at arm.com>
---
.../devicetree/bindings/arm/coherency-fabric.txt | 16 ++++
arch/arm/boot/dts/armada-370-xp.dtsi | 5 ++
arch/arm/mach-mvebu/Makefile | 2 +-
arch/arm/mach-mvebu/coherency.c | 82 ++++++++++++++++++++
arch/arm/mach-mvebu/coherency.h | 24 ++++++
arch/arm/mach-mvebu/coherency_ll.S | 49 ++++++++++++
arch/arm/mach-mvebu/common.h | 1 +
7 files changed, 178 insertions(+), 1 deletion(-)
create mode 100644 Documentation/devicetree/bindings/arm/coherency-fabric.txt
create mode 100644 arch/arm/mach-mvebu/coherency.c
create mode 100644 arch/arm/mach-mvebu/coherency.h
create mode 100644 arch/arm/mach-mvebu/coherency_ll.S
diff --git a/Documentation/devicetree/bindings/arm/coherency-fabric.txt b/Documentation/devicetree/bindings/arm/coherency-fabric.txt
new file mode 100644
index 0000000..2bfbf67
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/coherency-fabric.txt
@@ -0,0 +1,16 @@
+Coherency fabric
+----------------
+Available on Marvell SOCs: Armada 370 and Armada XP
+
+Required properties:
+
+- compatible: "marvell,coherency-fabric"
+- reg: Should contain,coherency fabric registers location and length.
+
+Example:
+
+coherency-fabric at d0020200 {
+ compatible = "marvell,coherency-fabric";
+ reg = <0xd0020200 0xb0>;
+};
+
diff --git a/arch/arm/boot/dts/armada-370-xp.dtsi b/arch/arm/boot/dts/armada-370-xp.dtsi
index 94b4b9e..b0d075b 100644
--- a/arch/arm/boot/dts/armada-370-xp.dtsi
+++ b/arch/arm/boot/dts/armada-370-xp.dtsi
@@ -36,6 +36,11 @@
interrupt-controller;
};
+ coherency-fabric at d0020200 {
+ compatible = "marvell,coherency-fabric";
+ reg = <0xd0020200 0xb0>;
+ };
+
soc {
#address-cells = <1>;
#size-cells = <1>;
diff --git a/arch/arm/mach-mvebu/Makefile b/arch/arm/mach-mvebu/Makefile
index 57f996b..5ce4b42 100644
--- a/arch/arm/mach-mvebu/Makefile
+++ b/arch/arm/mach-mvebu/Makefile
@@ -2,4 +2,4 @@ ccflags-$(CONFIG_ARCH_MULTIPLATFORM) := -I$(srctree)/$(src)/include \
-I$(srctree)/arch/arm/plat-orion/include
obj-y += system-controller.o
-obj-$(CONFIG_MACH_ARMADA_370_XP) += armada-370-xp.o irq-armada-370-xp.o addr-map.o
+obj-$(CONFIG_MACH_ARMADA_370_XP) += armada-370-xp.o irq-armada-370-xp.o addr-map.o coherency.o coherency_ll.o
diff --git a/arch/arm/mach-mvebu/coherency.c b/arch/arm/mach-mvebu/coherency.c
new file mode 100644
index 0000000..596ee66
--- /dev/null
+++ b/arch/arm/mach-mvebu/coherency.c
@@ -0,0 +1,82 @@
+/*
+ * Coherency fabric (Aurora) support for Armada 370 and XP platforms.
+ *
+ * Copyright (C) 2012 Marvell
+ *
+ * Yehuda Yitschak <yehuday at marvell.com>
+ * Gregory Clement <gregory.clement at free-electrons.com>
+ * Thomas Petazzoni <thomas.petazzoni at 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.
+ *
+ * The Armada 370 and Armada XP SOCs have a coherency fabric which is
+ * responsible for ensuring hardware coherency between all CPUs and between
+ * CPUs and I/O masters. This file initializes the coherency fabric and
+ * supplies basic routines for configuring and controlling hardware coherency
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/of_address.h>
+#include <linux/io.h>
+#include <linux/smp.h>
+#include <asm/smp_plat.h>
+#include "armada-370-xp.h"
+
+/*
+ * Some functions in this file are called very early during SMP
+ * initialization. At that time the device tree framework is not yet
+ * ready, and it is not possible to get the register address to
+ * ioremap it. That's why the pointer below is given with an initial
+ * value matching its virtual mapping
+ */
+static void __iomem *coherency_base = ARMADA_370_XP_REGS_VIRT_BASE + 0x20200;
+
+/* Coherency fabric registers */
+#define COHERENCY_FABRIC_CFG_OFFSET 0x4
+
+static struct of_device_id of_coherency_table[] = {
+ {.compatible = "marvell,coherency-fabric"},
+ { /* end of list */ },
+};
+
+#ifdef CONFIG_SMP
+int coherency_get_cpu_count(void)
+{
+ int reg, cnt;
+
+ reg = readl(coherency_base + COHERENCY_FABRIC_CFG_OFFSET);
+ cnt = (reg & 0xF) + 1;
+
+ return cnt;
+}
+#endif
+
+/* Function defined in coherency_ll.S */
+int ll_set_cpu_coherent(void __iomem *base_addr, unsigned int hw_cpu_id);
+
+int set_cpu_coherent(unsigned int hw_cpu_id, int smp_group_id)
+{
+ if (!coherency_base) {
+ pr_warn("Can't make CPU %d cache coherent.\n", hw_cpu_id);
+ pr_warn("Coherency fabric is not initialized\n");
+ return 1;
+ }
+
+ return ll_set_cpu_coherent(coherency_base, hw_cpu_id);
+}
+
+int __init coherency_init(void)
+{
+ struct device_node *np;
+
+ np = of_find_matching_node(NULL, of_coherency_table);
+ if (np) {
+ pr_info("Initializing Coherency fabric\n");
+ coherency_base = of_iomap(np, 0);
+ }
+
+ return 0;
+}
diff --git a/arch/arm/mach-mvebu/coherency.h b/arch/arm/mach-mvebu/coherency.h
new file mode 100644
index 0000000..2f42813
--- /dev/null
+++ b/arch/arm/mach-mvebu/coherency.h
@@ -0,0 +1,24 @@
+/*
+ * arch/arm/mach-mvebu/include/mach/coherency.h
+ *
+ *
+ * Coherency fabric (Aurora) support for Armada 370 and XP platforms.
+ *
+ * Copyright (C) 2012 Marvell
+ *
+ * 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.
+ */
+
+#ifndef __MACH_370_XP_COHERENCY_H
+#define __MACH_370_XP_COHERENCY_H
+
+#ifdef CONFIG_SMP
+int coherency_get_cpu_count(void);
+#endif
+
+int set_cpu_coherent(int cpu_id, int smp_group_id);
+int coherency_init(void);
+
+#endif /* __MACH_370_XP_COHERENCY_H */
diff --git a/arch/arm/mach-mvebu/coherency_ll.S b/arch/arm/mach-mvebu/coherency_ll.S
new file mode 100644
index 0000000..53e8391
--- /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 at 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)
diff --git a/arch/arm/mach-mvebu/common.h b/arch/arm/mach-mvebu/common.h
index 02f89ea..ba6b62a 100644
--- a/arch/arm/mach-mvebu/common.h
+++ b/arch/arm/mach-mvebu/common.h
@@ -20,4 +20,5 @@ void mvebu_restart(char mode, const char *cmd);
void armada_370_xp_init_irq(void);
void armada_370_xp_handle_irq(struct pt_regs *regs);
+int armada_370_xp_coherency_init(void);
#endif
--
1.7.9.5
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