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Diffstat (limited to 'arch/arm/mach-mvebu/coherency.c')
| -rw-r--r-- | arch/arm/mach-mvebu/coherency.c | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/arch/arm/mach-mvebu/coherency.c b/arch/arm/mach-mvebu/coherency.c new file mode 100644 index 0000000..8278960 --- /dev/null +++ b/arch/arm/mach-mvebu/coherency.c @@ -0,0 +1,155 @@ +/* + * 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; +} |