From 1bd4d8a6de5cda605e8b99fbf081be2ea2959380 Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Fri, 16 Jan 2015 17:11:29 +0100 Subject: [PATCH] ARM: mvebu: use arm_coherent_dma_ops and re-enable hardware I/O coherency Now that we have enabled automatic I/O synchronization barriers, we no longer need any explicit barriers. We can therefore simplify arch/arm/mach-mvebu/coherency.c by using the existing arm_coherent_dma_ops instead of our custom mvebu_hwcc_dma_ops, and re-enable hardware I/O coherency support. Signed-off-by: Thomas Petazzoni [Andrew Lunn : Remove forgotten comment] Signed-off-by: Andrew Lunn --- arch/arm/mach-mvebu/coherency.c | 58 ++------------------------------- 1 file changed, 3 insertions(+), 55 deletions(-) diff --git a/arch/arm/mach-mvebu/coherency.c b/arch/arm/mach-mvebu/coherency.c index caa21e9b8cd9..440799ba664a 100644 --- a/arch/arm/mach-mvebu/coherency.c +++ b/arch/arm/mach-mvebu/coherency.c @@ -33,6 +33,7 @@ #include #include #include +#include #include "coherency.h" #include "mvebu-soc-id.h" @@ -76,54 +77,6 @@ int set_cpu_coherent(void) return ll_enable_coherency(); } -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_notifier(struct notifier_block *nb, unsigned long event, void *__dev) { @@ -131,7 +84,7 @@ static int mvebu_hwcc_notifier(struct notifier_block *nb, if (event != BUS_NOTIFY_ADD_DEVICE) return NOTIFY_DONE; - set_dma_ops(dev, &mvebu_hwcc_dma_ops); + set_dma_ops(dev, &arm_coherent_dma_ops); return NOTIFY_OK; } @@ -246,14 +199,9 @@ static int coherency_type(void) return type; } -/* - * As a precaution, we currently completely disable hardware I/O - * coherency, until enough testing is done with automatic I/O - * synchronization barriers to validate that it is a proper solution. - */ int coherency_available(void) { - return false; + return coherency_type() != COHERENCY_FABRIC_TYPE_NONE; } int __init coherency_init(void) -- 2.20.1