OpenCloudOS-Kernel/arch/m68k/include/asm/atari_stram.h

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#ifndef _M68K_ATARI_STRAM_H
#define _M68K_ATARI_STRAM_H
/*
* Functions for Atari ST-RAM management
*/
/* public interface */
m68k/atari: Reserve some ST-RAM early on for device buffer use Based on an original patch from Michael Schmitz: Because mem_init() is now called before device init, devices that rely on ST-RAM may find all ST-RAM already allocated to other users by the time device init happens. In particular, a large initrd RAM disk may use up enough of ST-RAM to cause atari_stram_alloc() to resort to __get_dma_pages() allocation. In the current state of Atari memory management, all of RAM is marked DMA capable, so __get_dma_pages() may well return RAM that is not in actual fact DMA capable. Using this for frame buffer or SCSI DMA buffer causes subtle failure. The ST-RAM allocator has been changed to allocate memory from a pool of reserved ST-RAM of configurable size, set aside on ST-RAM init (i.e. before mem_init()). As long as this pool is not exhausted, allocation of real ST-RAM can be guaranteed. Other changes: - Replace the custom allocator in the ST-RAM pool by the existing allocator in the resource subsystem, - Remove mem_init_done and its hook, as memory init is now done before device init, - Remove /proc/stram, as ST-RAM usage now shows up under /proc/iomem, e.g. 005f2000-006f1fff : ST-RAM Pool 005f2000-0063dfff : atafb 0063e000-00641fff : ataflop 00642000-00642fff : SCSI Signed-off-by: Michael Schmitz <schmitz@debian.org> [Andreas Schwab <schwab@linux-m68k.org>: Use memparse()] [Geert: Use the resource subsystem instead of a custom allocator] Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2010-11-02 02:54:00 +08:00
void *atari_stram_alloc(unsigned long size, const char *owner);
void atari_stram_free(void *);
void *atari_stram_to_virt(unsigned long phys);
unsigned long atari_stram_to_phys(void *);
/* functions called internally by other parts of the kernel */
void atari_stram_init(void);
void atari_stram_reserve_pages(void *start_mem);
#endif /*_M68K_ATARI_STRAM_H */