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cab49bc95d
While the core resource handling code is safe, our global counter must still be protected against concurrent modifications. Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
124 lines
2.6 KiB
C
124 lines
2.6 KiB
C
/*
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** linux/amiga/chipram.c
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**
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** Modified 03-May-94 by Geert Uytterhoeven <geert@linux-m68k.org>
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** - 64-bit aligned allocations for full AGA compatibility
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**
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** Rewritten 15/9/2000 by Geert to use resource management
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*/
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/mm.h>
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#include <linux/init.h>
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#include <linux/ioport.h>
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#include <linux/slab.h>
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#include <linux/string.h>
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#include <linux/module.h>
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#include <asm/atomic.h>
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#include <asm/page.h>
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#include <asm/amigahw.h>
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unsigned long amiga_chip_size;
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EXPORT_SYMBOL(amiga_chip_size);
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static struct resource chipram_res = {
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.name = "Chip RAM", .start = CHIP_PHYSADDR
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};
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static atomic_t chipavail;
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void __init amiga_chip_init(void)
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{
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if (!AMIGAHW_PRESENT(CHIP_RAM))
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return;
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chipram_res.end = amiga_chip_size-1;
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request_resource(&iomem_resource, &chipram_res);
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atomic_set(&chipavail, amiga_chip_size);
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}
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void *amiga_chip_alloc(unsigned long size, const char *name)
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{
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struct resource *res;
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void *p;
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res = kzalloc(sizeof(struct resource), GFP_KERNEL);
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if (!res)
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return NULL;
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res->name = name;
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p = amiga_chip_alloc_res(size, res);
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if (!p) {
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kfree(res);
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return NULL;
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}
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return p;
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}
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EXPORT_SYMBOL(amiga_chip_alloc);
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/*
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* Warning:
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* amiga_chip_alloc_res is meant only for drivers that need to
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* allocate Chip RAM before kmalloc() is functional. As a consequence,
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* those drivers must not free that Chip RAM afterwards.
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*/
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void *amiga_chip_alloc_res(unsigned long size, struct resource *res)
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{
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int error;
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/* round up */
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size = PAGE_ALIGN(size);
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pr_debug("amiga_chip_alloc_res: allocate %lu bytes\n", size);
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error = allocate_resource(&chipram_res, res, size, 0, UINT_MAX,
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PAGE_SIZE, NULL, NULL);
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if (error < 0) {
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pr_err("amiga_chip_alloc_res: allocate_resource() failed %d!\n",
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error);
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return NULL;
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}
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atomic_sub(size, &chipavail);
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pr_debug("amiga_chip_alloc_res: returning %pR\n", res);
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return (void *)ZTWO_VADDR(res->start);
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}
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void amiga_chip_free(void *ptr)
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{
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unsigned long start = ZTWO_PADDR(ptr);
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struct resource **p, *res;
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unsigned long size;
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for (p = &chipram_res.child; (res = *p); p = &res->sibling) {
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if (res->start != start)
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continue;
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*p = res->sibling;
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size = res->end-start;
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pr_debug("amiga_chip_free: free %lu bytes at %p\n", size, ptr);
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atomic_add(size, &chipavail);
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kfree(res);
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return;
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}
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pr_err("amiga_chip_free: trying to free nonexistent region at %p\n",
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ptr);
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}
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EXPORT_SYMBOL(amiga_chip_free);
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unsigned long amiga_chip_avail(void)
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{
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unsigned long n = atomic_read(&chipavail);
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pr_debug("amiga_chip_avail : %lu bytes\n", n);
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return n;
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}
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EXPORT_SYMBOL(amiga_chip_avail);
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