Commit af6f23b8 authored by Christoph Hellwig's avatar Christoph Hellwig
Browse files

ARM/dma-mapping: use the generic versions of dma_to_phys/phys_to_dma by default 



Only the footbridge platforms provide their own DMA address translation
helpers, so switch to the generic version for all other platforms, and
consolidate the footbridge implementation to remove two levels of
indirection.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarArnd Bergmann <arnd@arndb.de>
Tested-by: default avatarMarc Zyngier <maz@kernel.org>
parent f9774cfd

arch/arm/Kconfig

+0 −1
Original line number Diff line number Diff line
@@ -15,7 +15,6 @@ config ARM 
	select ARCH_HAS_MEMBARRIER_SYNC_CORE

	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE

	select ARCH_HAS_PTE_SPECIAL if ARM_LPAE

	select ARCH_HAS_PHYS_TO_DMA

	select ARCH_HAS_SETUP_DMA_OPS

	select ARCH_HAS_SET_MEMORY

	select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL

arch/arm/include/asm/dma-direct.h

+1 −40
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0 */

#ifndef ASM_ARM_DMA_DIRECT_H

#define ASM_ARM_DMA_DIRECT_H 1



#include <asm/memory.h>



/*

 * dma_to_pfn/pfn_to_dma are architecture private

 * functions used internally by the DMA-mapping API to provide DMA

 * addresses. They must not be used by drivers.

 */

static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)

{

	if (dev && dev->dma_range_map)

		pfn = PFN_DOWN(translate_phys_to_dma(dev, PFN_PHYS(pfn)));

	return (dma_addr_t)__pfn_to_bus(pfn);

}



static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr)

{

	unsigned long pfn = __bus_to_pfn(addr);



	if (dev && dev->dma_range_map)

		pfn = PFN_DOWN(translate_dma_to_phys(dev, PFN_PHYS(pfn)));

	return pfn;

}



static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)

{

	unsigned int offset = paddr & ~PAGE_MASK;

	return pfn_to_dma(dev, __phys_to_pfn(paddr)) + offset;

}



static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)

{

	unsigned int offset = dev_addr & ~PAGE_MASK;

	return __pfn_to_phys(dma_to_pfn(dev, dev_addr)) + offset;

}



#endif /* ASM_ARM_DMA_DIRECT_H */
 
#include <mach/dma-direct.h>

arch/arm/include/asm/memory.h

+0 −2
Original line number Diff line number Diff line
@@ -378,8 +378,6 @@ static inline unsigned long __virt_to_idmap(unsigned long x) 
#ifndef __virt_to_bus

#define __virt_to_bus	__virt_to_phys

#define __bus_to_virt	__phys_to_virt

#define __pfn_to_bus(x)	__pfn_to_phys(x)

#define __bus_to_pfn(x)	__phys_to_pfn(x)

#endif



/*

arch/arm/mach-footbridge/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -60,6 +60,7 @@ endmenu 


# Footbridge support

config FOOTBRIDGE

	select ARCH_HAS_PHYS_TO_DMA

	bool



# Footbridge in host mode

arch/arm/mach-footbridge/common.c

+11 −8
Original line number Diff line number Diff line
@@ -12,6 +12,7 @@ 
#include <linux/init.h>

#include <linux/io.h>

#include <linux/spinlock.h>

#include <linux/dma-direct.h>

#include <video/vga.h>



#include <asm/page.h>
@@ -335,17 +336,19 @@ unsigned long __bus_to_virt(unsigned long res) 
	return res;

}

EXPORT_SYMBOL(__bus_to_virt);



unsigned long __pfn_to_bus(unsigned long pfn)

#else

static inline unsigned long fb_bus_sdram_offset(void)

{

	return __pfn_to_phys(pfn) + (fb_bus_sdram_offset() - PHYS_OFFSET);

	return BUS_OFFSET;

}

EXPORT_SYMBOL(__pfn_to_bus);

#endif /* CONFIG_FOOTBRIDGE_ADDIN */



unsigned long __bus_to_pfn(unsigned long bus)

dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)

{

	return __phys_to_pfn(bus - (fb_bus_sdram_offset() - PHYS_OFFSET));

	return paddr + (fb_bus_sdram_offset() - PHYS_OFFSET);

}

EXPORT_SYMBOL(__bus_to_pfn);



#endif
 
phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)

{

	return dev_addr - (fb_bus_sdram_offset() - PHYS_OFFSET);

}