linux/arch/arm/mach-iop13xx/include/mach/memory.h
Nicolas Pitre 58edb51572 [ARM] make page_to_dma() highmem aware
If a machine class has a custom __virt_to_bus() implementation then it
must provide a __arch_page_to_dma() implementation as well which is
_not_ based on page_address() to support highmem.

This patch fixes existing __arch_page_to_dma() and provide a default
implementation otherwise.  The default implementation for highmem is
based on __pfn_to_bus() which is defined only when no custom
__virt_to_bus() is provided by the machine class.

That leaves only ebsa110 and footbridge which cannot support highmem
until they provide their own __arch_page_to_dma() implementation.
But highmem support on those legacy platforms with limited memory is
certainly not a priority.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
2009-03-15 21:01:21 -04:00

73 lines
1.9 KiB
C

#ifndef __ASM_ARCH_MEMORY_H
#define __ASM_ARCH_MEMORY_H
#include <mach/hardware.h>
/*
* Physical DRAM offset.
*/
#define PHYS_OFFSET UL(0x00000000)
#ifndef __ASSEMBLY__
#if defined(CONFIG_ARCH_IOP13XX)
#define IOP13XX_PMMR_V_START (IOP13XX_PMMR_VIRT_MEM_BASE)
#define IOP13XX_PMMR_V_END (IOP13XX_PMMR_VIRT_MEM_BASE + IOP13XX_PMMR_SIZE)
#define IOP13XX_PMMR_P_START (IOP13XX_PMMR_PHYS_MEM_BASE)
#define IOP13XX_PMMR_P_END (IOP13XX_PMMR_PHYS_MEM_BASE + IOP13XX_PMMR_SIZE)
static inline dma_addr_t __virt_to_lbus(unsigned long x)
{
return x + IOP13XX_PMMR_PHYS_MEM_BASE - IOP13XX_PMMR_VIRT_MEM_BASE;
}
static inline unsigned long __lbus_to_virt(dma_addr_t x)
{
return x + IOP13XX_PMMR_VIRT_MEM_BASE - IOP13XX_PMMR_PHYS_MEM_BASE;
}
#define __is_lbus_dma(a) \
((a) >= IOP13XX_PMMR_P_START && (a) < IOP13XX_PMMR_P_END)
#define __is_lbus_virt(a) \
((a) >= IOP13XX_PMMR_V_START && (a) < IOP13XX_PMMR_V_END)
/* Device is an lbus device if it is on the platform bus of the IOP13XX */
#define is_lbus_device(dev) \
(dev && strncmp(dev->bus->name, "platform", 8) == 0)
#define __arch_dma_to_virt(dev, addr) \
({ \
unsigned long __virt; \
dma_addr_t __dma = addr; \
if (is_lbus_device(dev) && __is_lbus_dma(__dma)) \
__virt = __lbus_to_virt(__dma); \
else \
__virt = __phys_to_virt(__dma); \
(void *)__virt; \
})
#define __arch_virt_to_dma(dev, addr) \
({ \
unsigned long __virt = (unsigned long)addr; \
dma_addr_t __dma; \
if (is_lbus_device(dev) && __is_lbus_virt(__virt)) \
__dma = __virt_to_lbus(__virt); \
else \
__dma = __virt_to_phys(__virt); \
__dma; \
})
#define __arch_page_to_dma(dev, page) \
({ \
/* __is_lbus_virt() can never be true for RAM pages */ \
(dma_addr_t)page_to_phys(page); \
})
#endif /* CONFIG_ARCH_IOP13XX */
#endif /* !ASSEMBLY */
#define PFN_TO_NID(addr) (0)
#endif