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/*
** Dynamic DMA mapping support.
** See Documentation/DMA-mapping.txt for interface definitions.
**
** (c) Copyright 1999,2000 Hewlett-Packard Company
** (c) Copyright 2000 Grant Grundler
** (c) Copyright 2000 Philipp Rumpf <prumpf@tux.org>
** (c) Copyright 2000 John Marvin
**
** This implementation is for PA-RISC platforms that do not support
** I/O TLBs (aka DMA address translation hardware).
**
** "leveraged" from 2.3.47: arch/ia64/kernel/pci-dma.c.
** (I assume it's from David Mosberger-Tang but there was no Copyright)
**
** AFAIK, all PA7100LC and PA7300LC platforms can use this code.
** All PA2.0 machines but V-class can alias xxx_alloc_consistent()
** to use regular cacheable memory.
**
** - ggg
*/
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <asm/uaccess.h>
#include <asm/pgalloc.h>
#include <asm/io.h>
#include <asm/page.h> /* get_order */
#include <asm/dma.h> /* for DMA_CHUNK_SIZE */
#include <linux/proc_fs.h>
static struct proc_dir_entry * proc_gsc_root = NULL;
static int pcxl_proc_info(char *buffer, char **start, off_t offset, int length);
static unsigned long pcxl_used_bytes = 0;
static unsigned long pcxl_used_pages = 0;
extern unsigned long pcxl_dma_start; /* Start of pcxl dma mapping area */
static spinlock_t pcxl_res_lock;
static char *pcxl_res_map;
static int pcxl_res_hint;
static int pcxl_res_size;
#ifdef DEBUG_PCXL_RESOURCE
#define DBG_RES(x...) printk(x)
#else
#define DBG_RES(x...)
#endif
/*
** Dump a hex representation of the resource map.
*/
#ifdef DUMP_RESMAP
static
void dump_resmap(void)
{
u_long *res_ptr = (unsigned long *)pcxl_res_map;
u_long i = 0;
printk("res_map: ");
for(; i < (pcxl_res_size / sizeof(unsigned long)); ++i, ++res_ptr)
printk("%08lx ", *res_ptr);
printk("\n");
}
#else
static inline void dump_resmap(void) {;}
#endif
static int pa11_dma_supported( struct pci_dev *dev, u64 mask)
{
return 1;
}
static inline int map_pte_uncached(pte_t * pte,
unsigned long vaddr,
unsigned long size, unsigned long *paddr_ptr)
{
unsigned long end;
unsigned long orig_vaddr = vaddr;
vaddr &= ~PMD_MASK;
end = vaddr + size;
if (end > PMD_SIZE)
end = PMD_SIZE;
do {
if (!pte_none(*pte))
printk(KERN_ERR "map_pte_uncached: page already exists\n");
set_pte(pte, __mk_pte(*paddr_ptr, PAGE_KERNEL_UNC));
pdtlb_kernel(orig_vaddr);
vaddr += PAGE_SIZE;
orig_vaddr += PAGE_SIZE;
(*paddr_ptr) += PAGE_SIZE;
pte++;
} while (vaddr < end);
return 0;
}
static inline int map_pmd_uncached(pmd_t * pmd, unsigned long vaddr,
unsigned long size, unsigned long *paddr_ptr)
{
unsigned long end;
unsigned long orig_vaddr = vaddr;
vaddr &= ~PGDIR_MASK;
end = vaddr + size;
if (end > PGDIR_SIZE)
end = PGDIR_SIZE;
do {
pte_t * pte = pte_alloc_kernel(pmd, vaddr);
if (!pte)
return -ENOMEM;
if (map_pte_uncached(pte, orig_vaddr, end - vaddr, paddr_ptr))
return -ENOMEM;
vaddr = (vaddr + PMD_SIZE) & PMD_MASK;
orig_vaddr += PMD_SIZE;
pmd++;
} while (vaddr < end);
return 0;
}
static inline int map_uncached_pages(unsigned long vaddr, unsigned long size,
unsigned long paddr)
{
pgd_t * dir;
unsigned long end = vaddr + size;
dir = pgd_offset_k(vaddr);
do {
pmd_t *pmd;
pmd = pmd_alloc_kernel(dir, vaddr);
if (!pmd)
return -ENOMEM;
if (map_pmd_uncached(pmd, vaddr, end - vaddr, &paddr))
return -ENOMEM;
vaddr = vaddr + PGDIR_SIZE;
dir++;
} while (vaddr && (vaddr < end));
return 0;
}
static inline void unmap_uncached_pte(pmd_t * pmd, unsigned long vaddr,
unsigned long size)
{
pte_t * pte;
unsigned long end;
unsigned long orig_vaddr = vaddr;
if (pmd_none(*pmd))
return;
if (pmd_bad(*pmd)) {
pmd_ERROR(*pmd);
pmd_clear(pmd);
return;
}
pte = pte_offset(pmd, vaddr);
vaddr &= ~PMD_MASK;
end = vaddr + size;
if (end > PMD_SIZE)
end = PMD_SIZE;
do {
pte_t page = *pte;
pte_clear(pte);
pdtlb_kernel(orig_vaddr);
vaddr += PAGE_SIZE;
orig_vaddr += PAGE_SIZE;
pte++;
if (pte_none(page) || pte_present(page))
continue;
printk(KERN_CRIT "Whee.. Swapped out page in kernel page table\n");
} while (vaddr < end);
}
static inline void unmap_uncached_pmd(pgd_t * dir, unsigned long vaddr,
unsigned long size)
{
pmd_t * pmd;
unsigned long end;
unsigned long orig_vaddr = vaddr;
if (pgd_none(*dir))
return;
if (pgd_bad(*dir)) {
pgd_ERROR(*dir);
pgd_clear(dir);
return;
}
pmd = pmd_offset(dir, vaddr);
vaddr &= ~PGDIR_MASK;
end = vaddr + size;
if (end > PGDIR_SIZE)
end = PGDIR_SIZE;
do {
unmap_uncached_pte(pmd, orig_vaddr, end - vaddr);
vaddr = (vaddr + PMD_SIZE) & PMD_MASK;
orig_vaddr += PMD_SIZE;
pmd++;
} while (vaddr < end);
}
static void unmap_uncached_pages(unsigned long vaddr, unsigned long size)
{
pgd_t * dir;
unsigned long end = vaddr + size;
dir = pgd_offset_k(vaddr);
do {
unmap_uncached_pmd(dir, vaddr, end - vaddr);
vaddr = vaddr + PGDIR_SIZE;
dir++;
} while (vaddr && (vaddr < end));
}
#define PCXL_SEARCH_LOOP(idx, mask, size) \
for(; res_ptr < res_end; ++res_ptr) \
{ \
if(0 == ((*res_ptr) & mask)) { \
*res_ptr |= mask; \
idx = (int)((u_long)res_ptr - (u_long)pcxl_res_map); \
pcxl_res_hint = idx + (size >> 3); \
goto resource_found; \
} \
}
#define PCXL_FIND_FREE_MAPPING(idx, mask, size) { \
u##size *res_ptr = (u##size *)&(pcxl_res_map[pcxl_res_hint & ~((size >> 3) - 1)]); \
u##size *res_end = (u##size *)&pcxl_res_map[pcxl_res_size]; \
PCXL_SEARCH_LOOP(idx, mask, size); \
res_ptr = (u##size *)&pcxl_res_map[0]; \
PCXL_SEARCH_LOOP(idx, mask, size); \
}
unsigned long
pcxl_alloc_range(size_t size)
{
int res_idx;
u_long mask, flags;
unsigned int pages_needed = size >> PAGE_SHIFT;
ASSERT(pages_needed);
ASSERT((pages_needed * PAGE_SIZE) < DMA_CHUNK_SIZE);
ASSERT(pages_needed < (BITS_PER_LONG - PAGE_SHIFT));
mask = (u_long) -1L;
mask >>= BITS_PER_LONG - pages_needed;
DBG_RES("pcxl_alloc_range() size: %d pages_needed %d pages_mask 0x%08lx\n",
size, pages_needed, mask);
spin_lock_irqsave(&pcxl_res_lock, flags);
if(pages_needed <= 8) {
PCXL_FIND_FREE_MAPPING(res_idx, mask, 8);
} else if(pages_needed <= 16) {
PCXL_FIND_FREE_MAPPING(res_idx, mask, 16);
} else if(pages_needed <= 32) {
PCXL_FIND_FREE_MAPPING(res_idx, mask, 32);
} else {
panic(__FILE__ ": pcxl_alloc_range() Too many pages to map.\n");
}
dump_resmap();
panic(__FILE__ ": pcxl_alloc_range() out of dma mapping resources\n");
resource_found:
DBG_RES("pcxl_alloc_range() res_idx %d mask 0x%08lx res_hint: %d\n",
res_idx, mask, pcxl_res_hint);
pcxl_used_pages += pages_needed;
pcxl_used_bytes += ((pages_needed >> 3) ? (pages_needed >> 3) : 1);
spin_unlock_irqrestore(&pcxl_res_lock, flags);
dump_resmap();
/*
** return the corresponding vaddr in the pcxl dma map
*/
return (pcxl_dma_start + (res_idx << (PAGE_SHIFT + 3)));
}
#define PCXL_FREE_MAPPINGS(idx, m, size) \
u##size *res_ptr = (u##size *)&(pcxl_res_map[(idx) + (((size >> 3) - 1) & (~((size >> 3) - 1)))]); \
ASSERT((*res_ptr & m) == m); \
*res_ptr &= ~m;
/*
** clear bits in the pcxl resource map
*/
static void
pcxl_free_range(unsigned long vaddr, size_t size)
{
u_long mask, flags;
unsigned int res_idx = (vaddr - pcxl_dma_start) >> (PAGE_SHIFT + 3);
unsigned int pages_mapped = size >> PAGE_SHIFT;
ASSERT(pages_mapped);
ASSERT((pages_mapped * PAGE_SIZE) < DMA_CHUNK_SIZE);
ASSERT(pages_mapped < (BITS_PER_LONG - PAGE_SHIFT));
mask = (u_long) -1L;
mask >>= BITS_PER_LONG - pages_mapped;
DBG_RES("pcxl_free_range() res_idx: %d size: %d pages_mapped %d mask 0x%08lx\n",
res_idx, size, pages_mapped, mask);
spin_lock_irqsave(&pcxl_res_lock, flags);
if(pages_mapped <= 8) {
PCXL_FREE_MAPPINGS(res_idx, mask, 8);
} else if(pages_mapped <= 16) {
PCXL_FREE_MAPPINGS(res_idx, mask, 16);
} else if(pages_mapped <= 32) {
PCXL_FREE_MAPPINGS(res_idx, mask, 32);
} else {
panic(__FILE__ ": pcxl_free_range() Too many pages to unmap.\n");
}
pcxl_used_pages -= (pages_mapped ? pages_mapped : 1);
pcxl_used_bytes -= ((pages_mapped >> 3) ? (pages_mapped >> 3) : 1);
spin_unlock_irqrestore(&pcxl_res_lock, flags);
dump_resmap();
}
static int __init
pcxl_dma_init(void)
{
if (pcxl_dma_start == 0)
return 0;
spin_lock_init(&pcxl_res_lock);
pcxl_res_size = PCXL_DMA_MAP_SIZE >> (PAGE_SHIFT + 3);
pcxl_res_hint = 0;
pcxl_res_map = (char *)__get_free_pages(GFP_KERNEL,
get_order(pcxl_res_size));
proc_gsc_root = proc_mkdir("gsc", 0);
create_proc_info_entry("dino", 0, proc_gsc_root, pcxl_proc_info);
return 0;
}
__initcall(pcxl_dma_init);
static void * pa11_dma_alloc_consistent (struct pci_dev *hwdev, size_t size, dma_addr_t *dma_handle)
{
unsigned long vaddr;
unsigned long paddr;
int order;
order = get_order(size);
size = 1 << (order + PAGE_SHIFT);
vaddr = pcxl_alloc_range(size);
paddr = __get_free_pages(GFP_ATOMIC, order);
flush_kernel_dcache_range(paddr, size);
paddr = __pa(paddr);
map_uncached_pages(vaddr, size, paddr);
*dma_handle = (dma_addr_t) paddr;
#if 0
/* This probably isn't needed to support EISA cards.
** ISA cards will certainly only support 24-bit DMA addressing.
** Not clear if we can, want, or need to support ISA.
*/
if (!hwdev || hwdev->dma_mask != 0xffffffff)
gfp |= GFP_DMA;
#endif
return (void *)vaddr;
}
static void pa11_dma_free_consistent (struct pci_dev *hwdev, size_t size, void *vaddr, dma_addr_t dma_handle)
{
int order;
order = get_order(size);
size = 1 << (order + PAGE_SHIFT);
unmap_uncached_pages((unsigned long)vaddr, size);
pcxl_free_range((unsigned long)vaddr, size);
free_pages((unsigned long)__va(dma_handle), order);
}
static dma_addr_t pa11_dma_map_single(struct pci_dev *dev, void *addr, size_t size, int direction)
{
if (direction == PCI_DMA_NONE) {
printk(KERN_ERR "pa11_dma_map_single(PCI_DMA_NONE) called by %p\n", __builtin_return_address(0));
BUG();
}
flush_kernel_dcache_range((unsigned long) addr, size);
return virt_to_phys(addr);
}
static void pa11_dma_unmap_single(struct pci_dev *dev, dma_addr_t dma_handle, size_t size, int direction)
{
if (direction == PCI_DMA_NONE) {
printk(KERN_ERR "pa11_dma_unmap_single(PCI_DMA_NONE) called by %p\n", __builtin_return_address(0));
BUG();
}
if (direction == PCI_DMA_TODEVICE)
return;
/*
* For PCI_DMA_FROMDEVICE this flush is not necessary for the
* simple map/unmap case. However, it IS necessary if if
* pci_dma_sync_single has been called and the buffer reused.
*/
flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle), size);
return;
}
static int pa11_dma_map_sg(struct pci_dev *dev, struct scatterlist *sglist, int nents, int direction)
{
int i;
if (direction == PCI_DMA_NONE)
BUG();
for (i = 0; i < nents; i++, sglist++ ) {
sg_dma_address(sglist) = (dma_addr_t) virt_to_phys(sglist->address);
sg_dma_len(sglist) = sglist->length;
flush_kernel_dcache_range((unsigned long)sglist->address,
sglist->length);
}
return nents;
}
static void pa11_dma_unmap_sg(struct pci_dev *dev, struct scatterlist *sglist, int nents, int direction)
{
int i;
if (direction == PCI_DMA_NONE)
BUG();
if (direction == PCI_DMA_TODEVICE)
return;
/* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
for (i = 0; i < nents; i++, sglist++ )
flush_kernel_dcache_range((unsigned long) sglist->address, sglist->length);
return;
}
static void pa11_dma_sync_single(struct pci_dev *dev, dma_addr_t dma_handle, size_t size, int direction)
{
if (direction == PCI_DMA_NONE)
BUG();
flush_kernel_dcache_range((unsigned long) phys_to_virt(dma_handle), size);
}
static void pa11_dma_sync_sg(struct pci_dev *dev, struct scatterlist *sglist, int nents, int direction)
{
int i;
/* once we do combining we'll need to use phys_to_virt(sg_dma_address(sglist)) */
for (i = 0; i < nents; i++, sglist++ )
flush_kernel_dcache_range((unsigned long) sglist->address, sglist->length);
}
struct pci_dma_ops pcxl_dma_ops = {
pa11_dma_supported, /* dma_support */
pa11_dma_alloc_consistent,
pa11_dma_free_consistent,
pa11_dma_map_single, /* map_single */
pa11_dma_unmap_single, /* unmap_single */
pa11_dma_map_sg, /* map_sg */
pa11_dma_unmap_sg, /* unmap_sg */
pa11_dma_sync_single, /* dma_sync_single */
pa11_dma_sync_sg /* dma_sync_sg */
};
static void *fail_alloc_consistent(struct pci_dev *hwdev, size_t size,
dma_addr_t *dma_handle)
{
return NULL;
}
static void fail_free_consistent(struct pci_dev *dev, size_t size,
void *vaddr, dma_addr_t iova)
{
return;
}
struct pci_dma_ops pcx_dma_ops = {
pa11_dma_supported, /* dma_support */
fail_alloc_consistent,
fail_free_consistent,
pa11_dma_map_single, /* map_single */
pa11_dma_unmap_single, /* unmap_single */
pa11_dma_map_sg, /* map_sg */
pa11_dma_unmap_sg, /* unmap_sg */
pa11_dma_sync_single, /* dma_sync_single */
pa11_dma_sync_sg /* dma_sync_sg */
};
struct pci_dma_ops *hppa_dma_ops;
static int pcxl_proc_info(char *buf, char **start, off_t offset, int len)
{
u_long i = 0;
unsigned long *res_ptr = (u_long *)pcxl_res_map;
unsigned long total_pages = pcxl_res_size << 3; /* 8 bits per byte */
sprintf(buf, "\nDMA Mapping Area size : %d bytes (%d pages)\n",
PCXL_DMA_MAP_SIZE,
(pcxl_res_size << 3) ); /* 1 bit per page */
sprintf(buf, "%sResource bitmap : %d bytes (%d pages)\n",
buf, pcxl_res_size, pcxl_res_size << 3); /* 8 bits per byte */
strcat(buf, " total: free: used: % used:\n");
sprintf(buf, "%sblocks %8d %8ld %8ld %8ld%%\n", buf, pcxl_res_size,
pcxl_res_size - pcxl_used_bytes, pcxl_used_bytes,
(pcxl_used_bytes * 100) / pcxl_res_size);
sprintf(buf, "%spages %8ld %8ld %8ld %8ld%%\n", buf, total_pages,
total_pages - pcxl_used_pages, pcxl_used_pages,
(pcxl_used_pages * 100 / total_pages));
strcat(buf, "\nResource bitmap:");
for(; i < (pcxl_res_size / sizeof(u_long)); ++i, ++res_ptr) {
if ((i & 7) == 0)
strcat(buf,"\n ");
sprintf(buf, "%s %08lx", buf, *res_ptr);
}
strcat(buf, "\n");
return strlen(buf);
}
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