arch/sh/include/cpu-sh3/cpu/dma-register.h
Source file repositories/reference/linux-study-clean/arch/sh/include/cpu-sh3/cpu/dma-register.h
File Facts
- System
- Linux kernel
- Corpus path
arch/sh/include/cpu-sh3/cpu/dma-register.h- Extension
.h- Size
- 855 bytes
- Lines
- 39
- Domain
- Architecture Layer
- Bucket
- arch/sh
- Inferred role
- Architecture Layer: implementation source
- Status
- source implementation candidate
Why This File Exists
CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.
- CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.
Dependency Surface
- No C-style include directives detected by the generator.
Detected Declarations
- No top-level syscall, struct, function, initcall, or export declaration detected by the generator.
Annotated Snippet
#ifndef CPU_DMA_REGISTER_H
#define CPU_DMA_REGISTER_H
#define CHCR_TS_LOW_MASK 0x18
#define CHCR_TS_LOW_SHIFT 3
#define CHCR_TS_HIGH_MASK 0
#define CHCR_TS_HIGH_SHIFT 0
#define DMAOR_INIT DMAOR_DME
/*
* The SuperH DMAC supports a number of transmit sizes, we list them here,
* with their respective values as they appear in the CHCR registers.
*/
enum {
XMIT_SZ_8BIT,
XMIT_SZ_16BIT,
XMIT_SZ_32BIT,
XMIT_SZ_128BIT,
};
/* log2(size / 8) - used to calculate number of transfers */
#define TS_SHIFT { \
[XMIT_SZ_8BIT] = 0, \
[XMIT_SZ_16BIT] = 1, \
[XMIT_SZ_32BIT] = 2, \
[XMIT_SZ_128BIT] = 4, \
}
#define TS_INDEX2VAL(i) (((i) & 3) << CHCR_TS_LOW_SHIFT)
#endif
Annotation
- Atlas domain: Architecture Layer / arch/sh.
- Implementation status: source implementation candidate.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.