112 lines
2.6 KiB
C
112 lines
2.6 KiB
C
/*
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* early_ioremap() support for ARM
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*
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* Based on existing support in arch/x86/mm/ioremap.c
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*
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* Restrictions: currently only functional before paging_init()
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*/
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#include <linux/init.h>
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#include <linux/io.h>
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#include <asm/fixmap.h>
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#include <asm/pgalloc.h>
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#include <asm/pgtable.h>
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#include <asm/tlbflush.h>
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#include <asm/mach/map.h>
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static pte_t bm_pte[PTRS_PER_PTE + PTE_HWTABLE_PTRS]
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__aligned(PTE_HWTABLE_OFF + PTE_HWTABLE_SIZE) __initdata;
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static inline pmd_t * __init early_ioremap_pmd(unsigned long addr)
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{
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unsigned int index = pgd_index(addr);
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pgd_t *pgd = cpu_get_pgd() + index;
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pud_t *pud = pud_offset(pgd, addr);
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pmd_t *pmd = pmd_offset(pud, addr);
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return pmd;
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}
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static inline pte_t * __init early_ioremap_pte(unsigned long addr)
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{
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return &bm_pte[pte_index(addr)];
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}
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void __init early_ioremap_init(void)
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{
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pmd_t *pmd;
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pmd = early_ioremap_pmd(fix_to_virt(FIX_BTMAP_BEGIN));
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pmd_populate_kernel(NULL, pmd, bm_pte);
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/*
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* Make sure we don't span multiple pmds.
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*/
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BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
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!= (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
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if (pmd != early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END))) {
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WARN_ON(1);
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pr_warn("pmd %p != %p\n",
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pmd, early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END)));
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pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
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fix_to_virt(FIX_BTMAP_BEGIN));
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pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n",
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fix_to_virt(FIX_BTMAP_END));
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pr_warn("FIX_BTMAP_END: %d\n", FIX_BTMAP_END);
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pr_warn("FIX_BTMAP_BEGIN: %d\n", FIX_BTMAP_BEGIN);
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}
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early_ioremap_setup();
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}
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void __init __early_set_fixmap(enum fixed_addresses idx,
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phys_addr_t phys, pgprot_t flags)
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{
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unsigned long addr = __fix_to_virt(idx);
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pte_t *pte;
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u64 desc;
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if (idx > FIX_KMAP_END) {
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BUG();
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return;
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}
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pte = early_ioremap_pte(addr);
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if (pgprot_val(flags))
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set_pte_at(NULL, addr, pte, pfn_pte(phys >> PAGE_SHIFT, flags));
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else
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pte_clear(NULL, addr, pte);
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flush_tlb_kernel_range(addr, addr + PAGE_SIZE);
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desc = *pte;
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}
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void __init early_ioremap_shutdown(void)
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{
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int i;
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pmd_clear(early_ioremap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)));
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/* Create new entries for permanent mappings */
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for (i = 0; i < __end_of_permanent_fixed_addresses; i++) {
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pte_t *pte;
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struct map_desc map;
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map.virtual = fix_to_virt(i);
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pte = early_ioremap_pte(map.virtual);
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/* Only i/o device mappings are supported ATM */
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if (pte_none(*pte) ||
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(pte_val(*pte) & L_PTE_MT_MASK) != L_PTE_MT_DEV_SHARED)
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continue;
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map.pfn = pte_pfn(*pte);
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map.type = MT_DEVICE;
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map.length = PAGE_SIZE;
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create_mapping(&map);
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}
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}
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