highmem.h

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/* highmem.h: virtual kernel memory mappings for high memory
 *
 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells ([email protected])
 * - Derived from include/asm-i386/highmem.h
 *
 * See Documentation/frv/mmu-layout.txt for more information.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */

#ifndef _ASM_HIGHMEM_H
#define _ASM_HIGHMEM_H

#ifdef __KERNEL__

#include <linux/init.h>
#include <linux/highmem.h>
#include <asm/mem-layout.h>
#include <asm/spr-regs.h>
#include <asm/mb-regs.h>

#define NR_TLB_LINES        64  /* number of lines in the TLB */

#ifndef __ASSEMBLY__

#include <linux/interrupt.h>
#include <asm/kmap_types.h>
#include <asm/pgtable.h>

#ifdef CONFIG_DEBUG_HIGHMEM
#define HIGHMEM_DEBUG 1
#else
#define HIGHMEM_DEBUG 0
#endif

/* declarations for highmem.c */
extern unsigned long highstart_pfn, highend_pfn;

#define kmap_prot PAGE_KERNEL
#define kmap_pte ______kmap_pte_in_TLB
extern pte_t *pkmap_page_table;

#define flush_cache_kmaps()  do { } while (0)

/*
 * Right now we initialize only a single pte table. It can be extended
 * easily, subsequent pte tables have to be allocated in one physical
 * chunk of RAM.
 */
#define LAST_PKMAP  PTRS_PER_PTE
#define LAST_PKMAP_MASK (LAST_PKMAP - 1)
#define PKMAP_NR(virt)  ((virt - PKMAP_BASE) >> PAGE_SHIFT)
#define PKMAP_ADDR(nr)  (PKMAP_BASE + ((nr) << PAGE_SHIFT))

extern void *kmap_high(struct page *page);
extern void kunmap_high(struct page *page);

extern void *kmap(struct page *page);
extern void kunmap(struct page *page);

extern struct page *kmap_atomic_to_page(void *ptr);

#endif /* !__ASSEMBLY__ */

/*
 * The use of kmap_atomic/kunmap_atomic is discouraged - kmap/kunmap
 * gives a more generic (and caching) interface. But kmap_atomic can
 * be used in IRQ contexts, so in some (very limited) cases we need
 * it.
 */
#define KMAP_ATOMIC_CACHE_DAMR      8

#ifndef __ASSEMBLY__

#define __kmap_atomic_primary(cached, paddr, ampr)                      \
({                                              \
    unsigned long damlr, dampr;                             \
                                                \
    dampr = paddr | xAMPRx_L | xAMPRx_M | xAMPRx_S | xAMPRx_SS_16Kb | xAMPRx_V;     \
                                                \
    if (!cached)                                        \
        asm volatile("movgs %0,dampr"#ampr :: "r"(dampr) : "memory");           \
    else                                            \
        /* cache flush page attachment point */                     \
        asm volatile("movgs %0,iampr"#ampr"\n"                      \
                 "movgs %0,dampr"#ampr"\n"                      \
                 :: "r"(dampr) : "memory"                       \
                 );                                 \
                                                \
    asm("movsg damlr"#ampr",%0" : "=r"(damlr));                     \
                                                \
    /*printk("DAMR"#ampr": PRIM sl=%d L=%08lx P=%08lx\n", type, damlr, dampr);*/        \
                                                \
    (void *) damlr;                                     \
})

#define __kmap_atomic_secondary(slot, paddr)                              \
({                                                \
    unsigned long damlr = KMAP_ATOMIC_SECONDARY_FRAME + (slot) * PAGE_SIZE;           \
    unsigned long dampr = paddr | xAMPRx_L | xAMPRx_M | xAMPRx_S | xAMPRx_SS_16Kb | xAMPRx_V; \
                                                  \
    asm volatile("movgs %0,tplr \n"                               \
             "movgs %1,tppr \n"                               \
             "tlbpr %0,gr0,#2,#1"                             \
             : : "r"(damlr), "r"(dampr) : "memory");                      \
                                                  \
    /*printk("TLB: SECN sl=%d L=%08lx P=%08lx\n", slot, damlr, dampr);*/              \
                                                  \
    (void *) damlr;                                       \
})

static inline void *kmap_atomic_primary(struct page *page)
{
    unsigned long paddr;

    pagefault_disable();
    paddr = page_to_phys(page);

        return __kmap_atomic_primary(1, paddr, 2);
}

#define __kunmap_atomic_primary(cached, ampr)               \
do {                                    \
    asm volatile("movgs gr0,dampr"#ampr"\n" ::: "memory");      \
    if (cached)                         \
        asm volatile("movgs gr0,iampr"#ampr"\n" ::: "memory");  \
} while(0)

#define __kunmap_atomic_secondary(slot, vaddr)              \
do {                                    \
    asm volatile("tlbpr %0,gr0,#4,#1" : : "r"(vaddr) : "memory");   \
} while(0)

static inline void kunmap_atomic_primary(void *kvaddr)
{
        __kunmap_atomic_primary(1, 2);
    pagefault_enable();
}

void *kmap_atomic(struct page *page);
void __kunmap_atomic(void *kvaddr);

#endif /* !__ASSEMBLY__ */

#endif /* __KERNEL__ */

#endif /* _ASM_HIGHMEM_H */