linux/arch/mips/include/asm/mach-powertv/dma-coherence.h

118 lines
2.7 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Version from mach-generic modified to support PowerTV port
* Portions Copyright (C) 2009 Cisco Systems, Inc.
* Copyright (C) 2006 Ralf Baechle <ralf@linux-mips.org>
*
*/
#ifndef __ASM_MACH_POWERTV_DMA_COHERENCE_H
#define __ASM_MACH_POWERTV_DMA_COHERENCE_H
#include <linux/sched.h>
#include <linux/device.h>
#include <asm/mach-powertv/asic.h>
static inline bool is_kseg2(void *addr)
{
return (unsigned long)addr >= KSEG2;
}
static inline unsigned long virt_to_phys_from_pte(void *addr)
{
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
pte_t *ptep, pte;
unsigned long virt_addr = (unsigned long)addr;
unsigned long phys_addr = 0UL;
/* get the page global directory. */
pgd = pgd_offset_k(virt_addr);
if (!pgd_none(*pgd)) {
/* get the page upper directory */
pud = pud_offset(pgd, virt_addr);
if (!pud_none(*pud)) {
/* get the page middle directory */
pmd = pmd_offset(pud, virt_addr);
if (!pmd_none(*pmd)) {
/* get a pointer to the page table entry */
ptep = pte_offset(pmd, virt_addr);
pte = *ptep;
/* check for a valid page */
if (pte_present(pte)) {
/* get the physical address the page is
* referring to */
phys_addr = (unsigned long)
page_to_phys(pte_page(pte));
/* add the offset within the page */
phys_addr |= (virt_addr & ~PAGE_MASK);
}
}
}
}
return phys_addr;
}
static inline dma_addr_t plat_map_dma_mem(struct device *dev, void *addr,
size_t size)
{
if (is_kseg2(addr))
return phys_to_dma(virt_to_phys_from_pte(addr));
else
return phys_to_dma(virt_to_phys(addr));
}
static inline dma_addr_t plat_map_dma_mem_page(struct device *dev,
struct page *page)
{
return phys_to_dma(page_to_phys(page));
}
static inline unsigned long plat_dma_addr_to_phys(struct device *dev,
dma_addr_t dma_addr)
{
return dma_to_phys(dma_addr);
}
static inline void plat_unmap_dma_mem(struct device *dev, dma_addr_t dma_addr,
size_t size, enum dma_data_direction direction)
{
}
static inline int plat_dma_supported(struct device *dev, u64 mask)
{
/*
* we fall back to GFP_DMA when the mask isn't all 1s,
* so we can't guarantee allocations that must be
* within a tighter range than GFP_DMA..
*/
if (mask < DMA_BIT_MASK(24))
return 0;
return 1;
}
static inline void plat_extra_sync_for_device(struct device *dev)
{
}
static inline int plat_dma_mapping_error(struct device *dev,
dma_addr_t dma_addr)
{
return 0;
}
static inline int plat_device_is_coherent(struct device *dev)
{
return 0;
}
#endif /* __ASM_MACH_POWERTV_DMA_COHERENCE_H */