ARC: [Review] Multi-platform image #6: cpu-to-dma-addr optional

All the current platforms can work with 0x8000_0000 based dma_addr_t
since the Bus Bridges typically ignore the top bit (the only excpetion
was Angel4 PCI-AHB bridge which we no longer care for).
That way we don't need plat-specific cpu-addr to bus-addr conversion.

Hooks still provided - just in case a platform has an obscure device
which say needs 0 based bus address.

That way <asm/dma_mapping.h> no longer needs to unconditinally include
<plat/dma_addr.h>

Also verfied that on Angel4 board, other peripherals (IDE-disk / EMAC)
work fine with 0x8000_0000 based dma addresses.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 0 insertions, 45 deletions

diff --git a/arch/arc/plat-arcfpga/include/plat/dma_addr.h b/arch/arc/plat-arcfpga/include/plat/dma_addr.h
deleted file mode 100644
index 0e963431b729..000000000000
--- a/arch/arc/plat-arcfpga/include/plat/dma_addr.h
+++ /dev/null
@@ -1,45 +0,0 @@
-/*
- * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * vineetg: Feb 2009
- *  -For AA4 board, kernel to DMA address APIs
- */
-
-/*
- * kernel addresses are 0x800_000 based, while Bus addr are 0 based
- */
-
-#ifndef __PLAT_DMA_ADDR_H
-#define __PLAT_DMA_ADDR_H
-
-#include <linux/device.h>
-
-static inline unsigned long plat_dma_addr_to_kernel(struct device *dev,
-                                                    dma_addr_t dma_addr)
-{
-        return dma_addr + PAGE_OFFSET;
-}
-
-static inline dma_addr_t plat_kernel_addr_to_dma(struct device *dev, void *ptr)
-{
-        unsigned long addr = (unsigned long)ptr;
-        /*
-         * To Catch buggy drivers which can call DMA map API with kernel vaddr
-         * i.e. for buffers alloc via vmalloc or ioremap which are not
-         * gaurnateed to be PHY contiguous and hence unfit for DMA anyways.
-         * On ARC kernel virtual address is 0x7000_0000 to 0x7FFF_FFFF, so
-         * ideally we want to check this range here, but our implementation is
-         * better as it checks for even worse user virtual address as well.
-         */
-        if (likely(addr >= PAGE_OFFSET))
-                return addr - PAGE_OFFSET;
-
-        BUG();
-        return addr;
-}
-
-#endif