arch/powerpc/boot/wii.c

Source file repositories/reference/linux-study-clean/arch/powerpc/boot/wii.c

File Facts

System
Linux kernel
Corpus path
arch/powerpc/boot/wii.c
Extension
.c
Size
3008 bytes
Lines
154
Domain
Architecture Layer
Bucket
arch/powerpc
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.

Dependency Surface

Detected Declarations

Annotated Snippet

struct mipc_infohdr {
	char magic[3];
	u8 version;
	u32 mem2_boundary;
	u32 ipc_in;
	size_t ipc_in_size;
	u32 ipc_out;
	size_t ipc_out_size;
};

static int mipc_check_address(u32 pa)
{
	/* only MEM2 addresses */
	if (pa < 0x10000000 || pa > 0x14000000)
		return -EINVAL;
	return 0;
}

static struct mipc_infohdr *mipc_get_infohdr(void)
{
	struct mipc_infohdr **hdrp, *hdr;

	/* 'mini' header pointer is the last word of MEM2 memory */
	hdrp = (struct mipc_infohdr **)0x13fffffc;
	if (mipc_check_address((u32)hdrp)) {
		printf("mini: invalid hdrp %08X\n", (u32)hdrp);
		hdr = NULL;
		goto out;
	}

	hdr = *hdrp;
	if (mipc_check_address((u32)hdr)) {
		printf("mini: invalid hdr %08X\n", (u32)hdr);
		hdr = NULL;
		goto out;
	}
	if (memcmp(hdr->magic, "IPC", 3)) {
		printf("mini: invalid magic\n");
		hdr = NULL;
		goto out;
	}

out:
	return hdr;
}

static int mipc_get_mem2_boundary(u32 *mem2_boundary)
{
	struct mipc_infohdr *hdr;
	int error;

	hdr = mipc_get_infohdr();
	if (!hdr) {
		error = -1;
		goto out;
	}

	if (mipc_check_address(hdr->mem2_boundary)) {
		printf("mini: invalid mem2_boundary %08X\n",
		       hdr->mem2_boundary);
		error = -EINVAL;
		goto out;
	}
	*mem2_boundary = hdr->mem2_boundary;
	error = 0;
out:
	return error;

}

static void platform_fixups(void)
{
	void *mem;
	u32 reg[4];
	u32 mem2_boundary;
	int len;
	int error;

	mem = finddevice("/memory");
	if (!mem)
		fatal("Can't find memory node\n");

	/* two ranges of (address, size) words */
	len = getprop(mem, "reg", reg, sizeof(reg));
	if (len != sizeof(reg)) {
		/* nothing to do */
		goto out;
	}

	/* retrieve MEM2 boundary from 'mini' */

Annotation

Implementation Notes