arch/csky/mm/tcm.c

Source file repositories/reference/linux-study-clean/arch/csky/mm/tcm.c

File Facts

System
Linux kernel
Corpus path
arch/csky/mm/tcm.c
Extension
.c
Size
3855 bytes
Lines
170
Domain
Architecture Layer
Bucket
arch/csky
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

// SPDX-License-Identifier: GPL-2.0

#include <linux/highmem.h>
#include <linux/genalloc.h>
#include <asm/tlbflush.h>
#include <asm/fixmap.h>

#if (CONFIG_ITCM_RAM_BASE == 0xffffffff)
#error "You should define ITCM_RAM_BASE"
#endif

#ifdef CONFIG_HAVE_DTCM
#if (CONFIG_DTCM_RAM_BASE == 0xffffffff)
#error "You should define DTCM_RAM_BASE"
#endif

#if (CONFIG_DTCM_RAM_BASE == CONFIG_ITCM_RAM_BASE)
#error "You should define correct DTCM_RAM_BASE"
#endif
#endif

extern char __tcm_start, __tcm_end, __dtcm_start;

static struct gen_pool *tcm_pool;

static void __init tcm_mapping_init(void)
{
	pte_t *tcm_pte;
	unsigned long vaddr, paddr;
	int i;

	paddr = CONFIG_ITCM_RAM_BASE;

	if (pfn_valid(PFN_DOWN(CONFIG_ITCM_RAM_BASE)))
		goto panic;

#ifndef CONFIG_HAVE_DTCM
	for (i = 0; i < TCM_NR_PAGES; i++) {
#else
	for (i = 0; i < CONFIG_ITCM_NR_PAGES; i++) {
#endif
		vaddr = __fix_to_virt(FIX_TCM - i);

		tcm_pte =
			pte_offset_kernel((pmd_t *)pgd_offset_k(vaddr), vaddr);

		set_pte(tcm_pte, pfn_pte(__phys_to_pfn(paddr), PAGE_KERNEL));

		flush_tlb_one(vaddr);

		paddr = paddr + PAGE_SIZE;
	}

#ifdef CONFIG_HAVE_DTCM
	if (pfn_valid(PFN_DOWN(CONFIG_DTCM_RAM_BASE)))
		goto panic;

	paddr = CONFIG_DTCM_RAM_BASE;

	for (i = 0; i < CONFIG_DTCM_NR_PAGES; i++) {
		vaddr = __fix_to_virt(FIX_TCM - CONFIG_ITCM_NR_PAGES - i);

		tcm_pte =
			pte_offset_kernel((pmd_t *) pgd_offset_k(vaddr), vaddr);

		set_pte(tcm_pte, pfn_pte(__phys_to_pfn(paddr), PAGE_KERNEL));

		flush_tlb_one(vaddr);

		paddr = paddr + PAGE_SIZE;
	}
#endif

#ifndef CONFIG_HAVE_DTCM
	memcpy((void *)__fix_to_virt(FIX_TCM),
				&__tcm_start, &__tcm_end - &__tcm_start);

	pr_info("%s: mapping tcm va:0x%08lx to pa:0x%08x\n",
			__func__, __fix_to_virt(FIX_TCM), CONFIG_ITCM_RAM_BASE);

	pr_info("%s: __tcm_start va:0x%08lx size:%d\n",
			__func__, (unsigned long)&__tcm_start, &__tcm_end - &__tcm_start);
#else
	memcpy((void *)__fix_to_virt(FIX_TCM),
				&__tcm_start, &__dtcm_start - &__tcm_start);

	pr_info("%s: mapping itcm va:0x%08lx to pa:0x%08x\n",
			__func__, __fix_to_virt(FIX_TCM), CONFIG_ITCM_RAM_BASE);

	pr_info("%s: __itcm_start va:0x%08lx size:%d\n",

Annotation

Implementation Notes