korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-11-15 00:04:15 +08:00
Code Issues Packages Projects Releases Wiki Activity

[ARM] 3209/1: Configurable DMA-consistent memory region

Browse Source 
Patch from Kevin Hilman

This patch increase available DMA-consistent memory allocated by dma_coherent_alloc(). The default remains at 2M (defined in asm/memory.h) and each platform has the ability to override in asm/arch-foo/memory.h.

Signed-off-by: Kevin Hilman <kevin@hilman.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Kevin Hilman 2006-01-12 16:12:21 +00:00 committed by Russell King
parent a3e4943686
commit 37134cd55d
2 changed files with 50 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

53
arch/arm/mm/consistent.c
View File

@ -20,15 +20,25 @@
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
#include <asm/sizes.h>
/* Sanity check size */
#if (CONSISTENT_DMA_SIZE % SZ_2M)
#error "CONSISTENT_DMA_SIZE must be multiple of 2MiB"
#endif
#define CONSISTENT_BASE (0xffc00000)
#define CONSISTENT_END (0xffe00000)
#define CONSISTENT_BASE (CONSISTENT_END - CONSISTENT_DMA_SIZE)
#define CONSISTENT_OFFSET(x) (((unsigned long)(x) - CONSISTENT_BASE) >> PAGE_SHIFT)
#define CONSISTENT_PTE_INDEX(x) (((unsigned long)(x) - CONSISTENT_BASE) >> PGDIR_SHIFT)
#define NUM_CONSISTENT_PTES (CONSISTENT_DMA_SIZE >> PGDIR_SHIFT)
/*
* This is the page table (2MB) covering uncached, DMA consistent allocations
* These are the page tables (2MB each) covering uncached, DMA consistent allocations
*/
static pte_t *consistent_pte;
static pte_t *consistent_pte[NUM_CONSISTENT_PTES];
static DEFINE_SPINLOCK(consistent_lock);
/*
@ -142,7 +152,7 @@ __dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp,
unsigned long order;
u64 mask = ISA_DMA_THRESHOLD, limit;
if (!consistent_pte) {
if (!consistent_pte[0]) {
printk(KERN_ERR "%s: not initialised\n", __func__);
dump_stack();
return NULL;
@ -205,9 +215,12 @@ __dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp,
c = vm_region_alloc(&consistent_head, size,
gfp & ~(__GFP_DMA | __GFP_HIGHMEM));
if (c) {
pte_t *pte = consistent_pte + CONSISTENT_OFFSET(c->vm_start);
pte_t *pte;
struct page *end = page + (1 << order);
int idx = CONSISTENT_PTE_INDEX(c->vm_start);
u32 off = CONSISTENT_OFFSET(c->vm_start) & (PTRS_PER_PTE-1);
pte = consistent_pte[idx] + off;
c->vm_pages = page;
/*
@ -226,6 +239,11 @@ __dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp,
set_pte(pte, mk_pte(page, prot));
page++;
pte++;
off++;
if (off >= PTRS_PER_PTE) {
off = 0;
pte = consistent_pte[++idx];
}
} while (size -= PAGE_SIZE);
/*
@ -327,6 +345,8 @@ void dma_free_coherent(struct device *dev, size_t size, void *cpu_addr, dma_addr
struct vm_region *c;
unsigned long flags, addr;
pte_t *ptep;
int idx;
u32 off;
WARN_ON(irqs_disabled());
@ -347,7 +367,9 @@ void dma_free_coherent(struct device *dev, size_t size, void *cpu_addr, dma_addr
size = c->vm_end - c->vm_start;
}
ptep = consistent_pte + CONSISTENT_OFFSET(c->vm_start);
idx = CONSISTENT_PTE_INDEX(c->vm_start);
off = CONSISTENT_OFFSET(c->vm_start) & (PTRS_PER_PTE-1);
ptep = consistent_pte[idx] + off;
addr = c->vm_start;
do {
pte_t pte = ptep_get_and_clear(&init_mm, addr, ptep);
@ -355,6 +377,11 @@ void dma_free_coherent(struct device *dev, size_t size, void *cpu_addr, dma_addr
ptep++;
addr += PAGE_SIZE;
off++;
if (off >= PTRS_PER_PTE) {
off = 0;
ptep = consistent_pte[++idx];
}
if (!pte_none(pte) && pte_present(pte)) {
pfn = pte_pfn(pte);
@ -401,11 +428,12 @@ static int __init consistent_init(void)
pgd_t *pgd;
pmd_t *pmd;
pte_t *pte;
int ret = 0;
int ret = 0, i = 0;
u32 base = CONSISTENT_BASE;
do {
pgd = pgd_offset(&init_mm, CONSISTENT_BASE);
pmd = pmd_alloc(&init_mm, pgd, CONSISTENT_BASE);
pgd = pgd_offset(&init_mm, base);
pmd = pmd_alloc(&init_mm, pgd, base);
if (!pmd) {
printk(KERN_ERR "%s: no pmd tables\n", __func__);
ret = -ENOMEM;
@ -413,15 +441,16 @@ static int __init consistent_init(void)
}
WARN_ON(!pmd_none(*pmd));
pte = pte_alloc_kernel(pmd, CONSISTENT_BASE);
pte = pte_alloc_kernel(pmd, base);
if (!pte) {
printk(KERN_ERR "%s: no pte tables\n", __func__);
ret = -ENOMEM;
break;
}
consistent_pte = pte;
} while (0);
consistent_pte[i++] = pte;
base += (1 << PGDIR_SHIFT);
} while (base < CONSISTENT_END);
return ret;
}

9
include/asm-arm/memory.h
View File

@ -25,6 +25,7 @@
#include <linux/config.h>
#include <linux/compiler.h>
#include <asm/arch/memory.h>
#include <asm/sizes.h>
#ifndef TASK_SIZE
/*
@ -47,6 +48,14 @@
#define PAGE_OFFSET UL(0xc0000000)
#endif
/*
* Size of DMA-consistent memory region. Must be multiple of 2M,
* between 2MB and 14MB inclusive.
*/
#ifndef CONSISTENT_DMA_SIZE
#define CONSISTENT_DMA_SIZE SZ_2M
#endif
/*
* Physical vs virtual RAM address space conversion. These are
* private definitions which should NOT be used outside memory.h