arch/m68k/mm/sun3kmap.c

Source file repositories/reference/linux-study-clean/arch/m68k/mm/sun3kmap.c

File Facts

System
Linux kernel
Corpus path
arch/m68k/mm/sun3kmap.c
Extension
.c
Size
3399 bytes
Lines
160
Domain
Architecture Layer
Bucket
arch/m68k
Inferred role
Architecture Layer: exported/initcall integration point
Status
integration 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

#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/vmalloc.h>

#include <asm/page.h>
#include <asm/io.h>
#include <asm/sun3mmu.h>

#include "../sun3/sun3.h"

#undef SUN3_KMAP_DEBUG

extern void mmu_emu_map_pmeg (int context, int vaddr);

static inline void do_page_mapin(unsigned long phys, unsigned long virt,
				 unsigned long type)
{
	unsigned long pte;
	pte_t ptep;

	ptep = pfn_pte(phys >> PAGE_SHIFT, PAGE_KERNEL);
	pte = pte_val(ptep);
	pte |= type;

	sun3_put_pte(virt, pte);

#ifdef SUN3_KMAP_DEBUG
	pr_info("mapin:");
	print_pte_vaddr(virt);
#endif

}

static inline void do_pmeg_mapin(unsigned long phys, unsigned long virt,
				 unsigned long type, int pages)
{

	if(sun3_get_segmap(virt & ~SUN3_PMEG_MASK) == SUN3_INVALID_PMEG)
		mmu_emu_map_pmeg(sun3_get_context(), virt);

	while(pages) {
		do_page_mapin(phys, virt, type);
		phys += PAGE_SIZE;
		virt += PAGE_SIZE;
		pages--;
	}
}

void __iomem *sun3_ioremap(unsigned long phys, unsigned long size,
		   unsigned long type)
{
	struct vm_struct *area;
	unsigned long offset, virt, ret;
	int pages;

	if(!size)
		return NULL;

	/* page align */
	offset = phys & (PAGE_SIZE-1);
	phys &= ~(PAGE_SIZE-1);

	size += offset;
	size = PAGE_ALIGN(size);
	if((area = get_vm_area(size, VM_IOREMAP)) == NULL)
		return NULL;

#ifdef SUN3_KMAP_DEBUG
	pr_info("ioremap: got virt %p size %lx(%lx)\n", area->addr, size,
		area->size);
#endif

	pages = size / PAGE_SIZE;
	virt = (unsigned long)area->addr;
	ret = virt + offset;

	while(pages) {
		int seg_pages;

		seg_pages = (SUN3_PMEG_SIZE - (virt & SUN3_PMEG_MASK)) / PAGE_SIZE;
		if(seg_pages > pages)
			seg_pages = pages;

		do_pmeg_mapin(phys, virt, type, seg_pages);

		pages -= seg_pages;
		phys += seg_pages * PAGE_SIZE;
		virt += seg_pages * PAGE_SIZE;

Annotation

Implementation Notes