From f637a49e507c88354ab32b5d914e06acfb7ee00d Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Wed, 27 May 2009 13:44:50 +1000 Subject: powerpc: Minor cleanups of kernel virt address space definitions Make FIXADDR_TOP a compile time constant and cleanup a couple of definitions relative to the layout of the kernel address space on ppc32. We also print out that layout at boot time for debugging purposes. This is a pre-requisite for properly fixing non-coherent DMA allocactions. Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/pgtable-ppc32.h | 22 ++++++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-) (limited to 'arch/powerpc/include/asm/pgtable-ppc32.h') diff --git a/arch/powerpc/include/asm/pgtable-ppc32.h b/arch/powerpc/include/asm/pgtable-ppc32.h index ba45c997830f..28fe9d4bae35 100644 --- a/arch/powerpc/include/asm/pgtable-ppc32.h +++ b/arch/powerpc/include/asm/pgtable-ppc32.h @@ -10,7 +10,7 @@ extern unsigned long va_to_phys(unsigned long address); extern pte_t *va_to_pte(unsigned long address); -extern unsigned long ioremap_bot, ioremap_base; +extern unsigned long ioremap_bot; #ifdef CONFIG_44x extern int icache_44x_need_flush; @@ -55,9 +55,27 @@ extern int icache_44x_need_flush; #define pgd_ERROR(e) \ printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e)) +/* + * This is the bottom of the PKMAP area with HIGHMEM or an arbitrary + * value (for now) on others, from where we can start layout kernel + * virtual space that goes below PKMAP and FIXMAP + */ +#ifdef CONFIG_HIGHMEM +#define KVIRT_TOP PKMAP_BASE +#else +#define KVIRT_TOP (0xfe000000UL) /* for now, could be FIXMAP_BASE ? */ +#endif + +/* + * ioremap_bot starts at that address. Early ioremaps move down from there, + * until mem_init() at which point this becomes the top of the vmalloc + * and ioremap space + */ +#define IOREMAP_TOP KVIRT_TOP + /* * Just any arbitrary offset to the start of the vmalloc VM area: the - * current 64MB value just means that there will be a 64MB "hole" after the + * current 16MB value just means that there will be a 64MB "hole" after the * physical memory until the kernel virtual memory starts. That means that * any out-of-bounds memory accesses will hopefully be caught. * The vmalloc() routines leaves a hole of 4kB between each vmalloced -- cgit v1.2.3-59-g8ed1b From 8b31e49d1d75729c1da9009664ba52abd1adc628 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Wed, 27 May 2009 13:50:33 +1000 Subject: powerpc: Fix up dma_alloc_coherent() on platforms without cache coherency. The implementation we just revived has issues, such as using a Kconfig-defined virtual address area in kernel space that nothing actually carves out (and thus will overlap whatever is there), or having some dependencies on being self contained in a single PTE page which adds unnecessary constraints on the kernel virtual address space. This fixes it by using more classic PTE accessors and automatically locating the area for consistent memory, carving an appropriate hole in the kernel virtual address space, leaving only the size of that area as a Kconfig option. It also brings some dma-mask related fixes from the ARM implementation which was almost identical initially but grew its own fixes. Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/Kconfig | 13 ---- arch/powerpc/include/asm/dma-mapping.h | 6 +- arch/powerpc/include/asm/pgtable-ppc32.h | 4 ++ arch/powerpc/kernel/dma.c | 2 +- arch/powerpc/mm/dma-noncoherent.c | 108 ++++++++++++------------------- arch/powerpc/mm/mem.c | 4 ++ 6 files changed, 54 insertions(+), 83 deletions(-) (limited to 'arch/powerpc/include/asm/pgtable-ppc32.h') diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 3bb43adce44d..cdc9a6ff4be8 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -868,19 +868,6 @@ config TASK_SIZE default "0x80000000" if PPC_PREP || PPC_8xx default "0xc0000000" -config CONSISTENT_START_BOOL - bool "Set custom consistent memory pool address" - depends on ADVANCED_OPTIONS && NOT_COHERENT_CACHE - help - This option allows you to set the base virtual address - of the consistent memory pool. This pool of virtual - memory is used to make consistent memory allocations. - -config CONSISTENT_START - hex "Base virtual address of consistent memory pool" if CONSISTENT_START_BOOL - default "0xfd000000" if (NOT_COHERENT_CACHE && 8xx) - default "0xff100000" if NOT_COHERENT_CACHE - config CONSISTENT_SIZE_BOOL bool "Set custom consistent memory pool size" depends on ADVANCED_OPTIONS && NOT_COHERENT_CACHE diff --git a/arch/powerpc/include/asm/dma-mapping.h b/arch/powerpc/include/asm/dma-mapping.h index c69f2b5f0cc4..cb448d68452c 100644 --- a/arch/powerpc/include/asm/dma-mapping.h +++ b/arch/powerpc/include/asm/dma-mapping.h @@ -26,7 +26,9 @@ * allocate the space "normally" and use the cache management functions * to ensure it is consistent. */ -extern void *__dma_alloc_coherent(size_t size, dma_addr_t *handle, gfp_t gfp); +struct device; +extern void *__dma_alloc_coherent(struct device *dev, size_t size, + dma_addr_t *handle, gfp_t gfp); extern void __dma_free_coherent(size_t size, void *vaddr); extern void __dma_sync(void *vaddr, size_t size, int direction); extern void __dma_sync_page(struct page *page, unsigned long offset, @@ -37,7 +39,7 @@ extern void __dma_sync_page(struct page *page, unsigned long offset, * Cache coherent cores. */ -#define __dma_alloc_coherent(gfp, size, handle) NULL +#define __dma_alloc_coherent(dev, gfp, size, handle) NULL #define __dma_free_coherent(size, addr) ((void)0) #define __dma_sync(addr, size, rw) ((void)0) #define __dma_sync_page(pg, off, sz, rw) ((void)0) diff --git a/arch/powerpc/include/asm/pgtable-ppc32.h b/arch/powerpc/include/asm/pgtable-ppc32.h index 28fe9d4bae35..c9ff9d75990e 100644 --- a/arch/powerpc/include/asm/pgtable-ppc32.h +++ b/arch/powerpc/include/asm/pgtable-ppc32.h @@ -71,7 +71,11 @@ extern int icache_44x_need_flush; * until mem_init() at which point this becomes the top of the vmalloc * and ioremap space */ +#ifdef CONFIG_NOT_COHERENT_CACHE +#define IOREMAP_TOP ((KVIRT_TOP - CONFIG_CONSISTENT_SIZE) & PAGE_MASK) +#else #define IOREMAP_TOP KVIRT_TOP +#endif /* * Just any arbitrary offset to the start of the vmalloc VM area: the diff --git a/arch/powerpc/kernel/dma.c b/arch/powerpc/kernel/dma.c index 53c7788cba78..6b02793dc75b 100644 --- a/arch/powerpc/kernel/dma.c +++ b/arch/powerpc/kernel/dma.c @@ -32,7 +32,7 @@ void *dma_direct_alloc_coherent(struct device *dev, size_t size, { void *ret; #ifdef CONFIG_NOT_COHERENT_CACHE - ret = __dma_alloc_coherent(size, dma_handle, flag); + ret = __dma_alloc_coherent(dev, size, dma_handle, flag); if (ret == NULL) return NULL; *dma_handle += get_dma_direct_offset(dev); diff --git a/arch/powerpc/mm/dma-noncoherent.c b/arch/powerpc/mm/dma-noncoherent.c index b7dc4c19f582..36692f5c9a76 100644 --- a/arch/powerpc/mm/dma-noncoherent.c +++ b/arch/powerpc/mm/dma-noncoherent.c @@ -32,20 +32,21 @@ #include +#include "mmu_decl.h" + /* * This address range defaults to a value that is safe for all * platforms which currently set CONFIG_NOT_COHERENT_CACHE. It * can be further configured for specific applications under * the "Advanced Setup" menu. -Matt */ -#define CONSISTENT_BASE (CONFIG_CONSISTENT_START) -#define CONSISTENT_END (CONFIG_CONSISTENT_START + CONFIG_CONSISTENT_SIZE) +#define CONSISTENT_BASE (IOREMAP_TOP) +#define CONSISTENT_END (CONSISTENT_BASE + CONFIG_CONSISTENT_SIZE) #define CONSISTENT_OFFSET(x) (((unsigned long)(x) - CONSISTENT_BASE) >> PAGE_SHIFT) /* * This is the page table (2MB) covering uncached, DMA consistent allocations */ -static pte_t *consistent_pte; static DEFINE_SPINLOCK(consistent_lock); /* @@ -148,22 +149,38 @@ static struct ppc_vm_region *ppc_vm_region_find(struct ppc_vm_region *head, unsi * virtual and bus address for that space. */ void * -__dma_alloc_coherent(size_t size, dma_addr_t *handle, gfp_t gfp) +__dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp) { struct page *page; struct ppc_vm_region *c; unsigned long order; - u64 mask = 0x00ffffff, limit; /* ISA default */ + u64 mask = ISA_DMA_THRESHOLD, limit; - if (!consistent_pte) { - printk(KERN_ERR "%s: not initialised\n", __func__); - dump_stack(); - return NULL; + if (dev) { + mask = dev->coherent_dma_mask; + + /* + * Sanity check the DMA mask - it must be non-zero, and + * must be able to be satisfied by a DMA allocation. + */ + if (mask == 0) { + dev_warn(dev, "coherent DMA mask is unset\n"); + goto no_page; + } + + if ((~mask) & ISA_DMA_THRESHOLD) { + dev_warn(dev, "coherent DMA mask %#llx is smaller " + "than system GFP_DMA mask %#llx\n", + mask, (unsigned long long)ISA_DMA_THRESHOLD); + goto no_page; + } } + size = PAGE_ALIGN(size); limit = (mask + 1) & ~mask; - if ((limit && size >= limit) || size >= (CONSISTENT_END - CONSISTENT_BASE)) { + if ((limit && size >= limit) || + size >= (CONSISTENT_END - CONSISTENT_BASE)) { printk(KERN_WARNING "coherent allocation too big (requested %#x mask %#Lx)\n", size, mask); return NULL; @@ -171,6 +188,7 @@ __dma_alloc_coherent(size_t size, dma_addr_t *handle, gfp_t gfp) order = get_order(size); + /* Might be useful if we ever have a real legacy DMA zone... */ if (mask != 0xffffffff) gfp |= GFP_DMA; @@ -195,7 +213,6 @@ __dma_alloc_coherent(size_t size, dma_addr_t *handle, gfp_t gfp) gfp & ~(__GFP_DMA | __GFP_HIGHMEM)); if (c) { unsigned long vaddr = c->vm_start; - pte_t *pte = consistent_pte + CONSISTENT_OFFSET(vaddr); struct page *end = page + (1 << order); split_page(page, order); @@ -206,13 +223,10 @@ __dma_alloc_coherent(size_t size, dma_addr_t *handle, gfp_t gfp) *handle = page_to_phys(page); do { - BUG_ON(!pte_none(*pte)); - SetPageReserved(page); - set_pte_at(&init_mm, vaddr, - pte, mk_pte(page, pgprot_noncached(PAGE_KERNEL))); + map_page(vaddr, page_to_phys(page), + pgprot_noncached(PAGE_KERNEL)); page++; - pte++; vaddr += PAGE_SIZE; } while (size -= PAGE_SIZE); @@ -241,8 +255,7 @@ void __dma_free_coherent(size_t size, void *vaddr) { struct ppc_vm_region *c; unsigned long flags, addr; - pte_t *ptep; - + size = PAGE_ALIGN(size); spin_lock_irqsave(&consistent_lock, flags); @@ -258,29 +271,26 @@ void __dma_free_coherent(size_t size, void *vaddr) size = c->vm_end - c->vm_start; } - ptep = consistent_pte + CONSISTENT_OFFSET(c->vm_start); addr = c->vm_start; do { - pte_t pte = ptep_get_and_clear(&init_mm, addr, ptep); + pte_t *ptep; unsigned long pfn; - ptep++; - addr += PAGE_SIZE; - - if (!pte_none(pte) && pte_present(pte)) { - pfn = pte_pfn(pte); - + ptep = pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(addr), + addr), + addr), + addr); + if (!pte_none(*ptep) && pte_present(*ptep)) { + pfn = pte_pfn(*ptep); + pte_clear(&init_mm, addr, ptep); if (pfn_valid(pfn)) { struct page *page = pfn_to_page(pfn); - ClearPageReserved(page); + ClearPageReserved(page); __free_page(page); - continue; } } - - printk(KERN_CRIT "%s: bad page in kernel page table\n", - __func__); + addr += PAGE_SIZE; } while (size -= PAGE_SIZE); flush_tlb_kernel_range(c->vm_start, c->vm_end); @@ -300,42 +310,6 @@ void __dma_free_coherent(size_t size, void *vaddr) } EXPORT_SYMBOL(__dma_free_coherent); -/* - * Initialise the consistent memory allocation. - */ -static int __init dma_alloc_init(void) -{ - pgd_t *pgd; - pud_t *pud; - pmd_t *pmd; - pte_t *pte; - int ret = 0; - - do { - pgd = pgd_offset(&init_mm, CONSISTENT_BASE); - pud = pud_alloc(&init_mm, pgd, CONSISTENT_BASE); - pmd = pmd_alloc(&init_mm, pud, CONSISTENT_BASE); - if (!pmd) { - printk(KERN_ERR "%s: no pmd tables\n", __func__); - ret = -ENOMEM; - break; - } - - pte = pte_alloc_kernel(pmd, CONSISTENT_BASE); - if (!pte) { - printk(KERN_ERR "%s: no pte tables\n", __func__); - ret = -ENOMEM; - break; - } - - consistent_pte = pte; - } while (0); - - return ret; -} - -core_initcall(dma_alloc_init); - /* * make an area consistent. */ diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index d3a4e67561fa..579382c163a9 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -387,6 +387,10 @@ void __init mem_init(void) pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n", PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP)); #endif /* CONFIG_HIGHMEM */ +#ifdef CONFIG_NOT_COHERENT_CACHE + pr_info(" * 0x%08lx..0x%08lx : consistent mem\n", + IOREMAP_TOP, IOREMAP_TOP + CONFIG_CONSISTENT_SIZE); +#endif /* CONFIG_NOT_COHERENT_CACHE */ pr_info(" * 0x%08lx..0x%08lx : early ioremap\n", ioremap_bot, IOREMAP_TOP); pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n", -- cgit v1.2.3-59-g8ed1b