[질문] kernel의 include/linux/ioport.h에 있는 io resource flags에 대하여

kernel의 include/linux/ioport.h에 있는 io resource flags에 대하여
설명좀 부탁드립니다.

혹여 참고할 만한 자료가 있으면 부탁드립니다.

참고로, sdram에 약 2Mb 정도를 할당하여 전용으로 사용하고자 합니다.
즉, 특정 physical address를 다른 것들은 사용하지 못하게 하고, phys_to_virt()를
이용하여 virtual address를 구하여 커널 동작중에 사용하려고 합니다.
그래서, request_resource()이용하려고 합니다.

/*
* IO resources have these defined flags.
*/
#define IORESOURCE_BITS 0x000000ff /* Bus-specific bits */

#define IORESOURCE_IO 0x00000100 /* Resource type */
#define IORESOURCE_MEM 0x00000200
#define IORESOURCE_IRQ 0x00000400
#define IORESOURCE_DMA 0x00000800

#define IORESOURCE_PREFETCH 0x00001000 /* No side effects */
#define IORESOURCE_READONLY 0x00002000
#define IORESOURCE_CACHEABLE 0x00004000
#define IORESOURCE_RANGELENGTH 0x00008000
#define IORESOURCE_SHADOWABLE 0x00010000
#define IORESOURCE_BUS_HAS_VGA 0x00080000

#define IORESOURCE_UNSET 0x20000000
#define IORESOURCE_AUTO 0x40000000
#define IORESOURCE_BUSY 0x80000000 /* Driver has marked this resource busy
*/

/* ISA PnP IRQ specific bits (IORESOURCE_BITS) */
#define IORESOURCE_IRQ_HIGHEDGE (1<<0)
#define IORESOURCE_IRQ_LOWEDGE (1<<1)
#define IORESOURCE_IRQ_HIGHLEVEL (1<<2)
#define IORESOURCE_IRQ_LOWLEVEL (1<<3)

/* ISA PnP DMA specific bits (IORESOURCE_BITS) */
#define IORESOURCE_DMA_TYPE_MASK (3<<0)
#define IORESOURCE_DMA_8BIT (0<<0)
#define IORESOURCE_DMA_8AND16BIT (1<<0)
#define IORESOURCE_DMA_16BIT (2<<0)

#define IORESOURCE_DMA_MASTER (1<<2)
#define IORESOURCE_DMA_BYTE (1<<3)
#define IORESOURCE_DMA_WORD (1<<4)

#define IORESOURCE_DMA_SPEED_MASK (3<<6)
#define IORESOURCE_DMA_COMPATIBLE (0<<6)
#define IORESOURCE_DMA_TYPEA (1<<6)
#define IORESOURCE_DMA_TYPEB (2<<6)
#define IORESOURCE_DMA_TYPEF (3<<6)

/* ISA PnP memory I/O specific bits (IORESOURCE_BITS) */
#define IORESOURCE_MEM_WRITEABLE (1<<0) /* dup: IORESOURCE_READONLY */
#define IORESOURCE_MEM_CACHEABLE (1<<1) /* dup: IORESOURCE_CACHEABLE */
#define IORESOURCE_MEM_RANGELENGTH (1<<2) /* dup: IORESOURCE_RANGELENGTH */
#define IORESOURCE_MEM_TYPE_MASK (3<<3)
#define IORESOURCE_MEM_8BIT (0<<3)
#define IORESOURCE_MEM_16BIT (1<<3)
#define IORESOURCE_MEM_8AND16BIT (2<<3)
#define IORESOURCE_MEM_SHADOWABLE (1<<5) /* dup: IORESOURCE_SHADOWABLE */
#define IORESOURCE_MEM_EXPANSIONROM (1<<6)