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-rw-r--r--arch/arm/mach-mvebu/coherency.c155
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diff --git a/arch/arm/mach-mvebu/coherency.c b/arch/arm/mach-mvebu/coherency.c
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+/*
+ * Coherency fabric (Aurora) support for Armada 370 and XP platforms.
+ *
+ * Copyright (C) 2012 Marvell
+ *
+ * Yehuda Yitschak <yehuday@marvell.com>
+ * Gregory Clement <gregory.clement@free-electrons.com>
+ * Thomas Petazzoni <thomas.petazzoni@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 <linux/dma-mapping.h>
+#include <linux/platform_device.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;
+static void __iomem *coherency_cpu_base;
+
+/* Coherency fabric registers */
+#define COHERENCY_FABRIC_CFG_OFFSET 0x4
+
+#define IO_SYNC_BARRIER_CTL_OFFSET 0x0
+
+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);
+}
+
+static inline void mvebu_hwcc_sync_io_barrier(void)
+{
+ writel(0x1, coherency_cpu_base + IO_SYNC_BARRIER_CTL_OFFSET);
+ while (readl(coherency_cpu_base + IO_SYNC_BARRIER_CTL_OFFSET) & 0x1);
+}
+
+static dma_addr_t mvebu_hwcc_dma_map_page(struct device *dev, struct page *page,
+ unsigned long offset, size_t size,
+ enum dma_data_direction dir,
+ struct dma_attrs *attrs)
+{
+ if (dir != DMA_TO_DEVICE)
+ mvebu_hwcc_sync_io_barrier();
+ return pfn_to_dma(dev, page_to_pfn(page)) + offset;
+}
+
+
+static void mvebu_hwcc_dma_unmap_page(struct device *dev, dma_addr_t dma_handle,
+ size_t size, enum dma_data_direction dir,
+ struct dma_attrs *attrs)
+{
+ if (dir != DMA_TO_DEVICE)
+ mvebu_hwcc_sync_io_barrier();
+}
+
+static void mvebu_hwcc_dma_sync(struct device *dev, dma_addr_t dma_handle,
+ size_t size, enum dma_data_direction dir)
+{
+ if (dir != DMA_TO_DEVICE)
+ mvebu_hwcc_sync_io_barrier();
+}
+
+static struct dma_map_ops mvebu_hwcc_dma_ops = {
+ .alloc = arm_dma_alloc,
+ .free = arm_dma_free,
+ .mmap = arm_dma_mmap,
+ .map_page = mvebu_hwcc_dma_map_page,
+ .unmap_page = mvebu_hwcc_dma_unmap_page,
+ .get_sgtable = arm_dma_get_sgtable,
+ .map_sg = arm_dma_map_sg,
+ .unmap_sg = arm_dma_unmap_sg,
+ .sync_single_for_cpu = mvebu_hwcc_dma_sync,
+ .sync_single_for_device = mvebu_hwcc_dma_sync,
+ .sync_sg_for_cpu = arm_dma_sync_sg_for_cpu,
+ .sync_sg_for_device = arm_dma_sync_sg_for_device,
+ .set_dma_mask = arm_dma_set_mask,
+};
+
+static int mvebu_hwcc_platform_notifier(struct notifier_block *nb,
+ unsigned long event, void *__dev)
+{
+ struct device *dev = __dev;
+
+ if (event != BUS_NOTIFY_ADD_DEVICE)
+ return NOTIFY_DONE;
+ set_dma_ops(dev, &mvebu_hwcc_dma_ops);
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block mvebu_hwcc_platform_nb = {
+ .notifier_call = mvebu_hwcc_platform_notifier,
+};
+
+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);
+ coherency_cpu_base = of_iomap(np, 1);
+ set_cpu_coherent(cpu_logical_map(smp_processor_id()), 0);
+ bus_register_notifier(&platform_bus_type,
+ &mvebu_hwcc_platform_nb);
+ }
+
+ return 0;
+}