drivers/gpu/drm/radeon/kv_smc.c

Source file repositories/reference/linux-study-clean/drivers/gpu/drm/radeon/kv_smc.c

File Facts

System
Linux kernel
Corpus path
drivers/gpu/drm/radeon/kv_smc.c
Extension
.c
Size
4866 bytes
Lines
215
Domain
Driver Families
Bucket
drivers/gpu
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

while (count > 0) {
			if (t_byte > 0) {
				mask = (mask << 8) | 0xff;
				t_byte--;
			} else if (byte_count > 0) {
				data = (data << 8) + *src++;
				byte_count--;
				mask <<= 8;
			} else {
				data <<= 8;
				mask = (mask << 8) | 0xff;
			}
			count--;
		}

		data |= original_data & mask;

		ret = kv_set_smc_sram_address(rdev, addr, limit);
		if (ret)
			return ret;

		WREG32(SMC_IND_DATA_0, data);

		addr += 4;
	}

	while (byte_count >= 4) {
		/* SMC address space is BE */
		data = (src[0] << 24) + (src[1] << 16) + (src[2] << 8) + src[3];

		ret = kv_set_smc_sram_address(rdev, addr, limit);
		if (ret)
			return ret;

		WREG32(SMC_IND_DATA_0, data);

		src += 4;
		byte_count -= 4;
		addr += 4;
	}

	/* RMW for the final bytes */
	if (byte_count > 0) {
		data = 0;

		ret = kv_set_smc_sram_address(rdev, addr, limit);
		if (ret)
			return ret;

		original_data = RREG32(SMC_IND_DATA_0);

		extra_shift = 8 * (4 - byte_count);

		while (byte_count > 0) {
			/* SMC address space is BE */
			data = (data << 8) + *src++;
			byte_count--;
		}

		data <<= extra_shift;

		data |= (original_data & ~((~0UL) << extra_shift));

		ret = kv_set_smc_sram_address(rdev, addr, limit);
		if (ret)
			return ret;

		WREG32(SMC_IND_DATA_0, data);
	}
	return 0;
}

Annotation

Implementation Notes