From 25078dc1f74be16b858e914f52cc8f4d03c2271a Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Sun, 16 Dec 2018 17:53:49 +0100 Subject: powerpc: use mm zones more sensibly Powerpc has somewhat odd usage where ZONE_DMA is used for all memory on common 64-bit configfs, and ZONE_DMA32 is used for 31-bit schemes. Move to a scheme closer to what other architectures use (and I dare to say the intent of the system): - ZONE_DMA: optionally for memory < 31-bit (64-bit embedded only) - ZONE_NORMAL: everything addressable by the kernel - ZONE_HIGHMEM: memory > 32-bit for 32-bit kernels Also provide information on how ZONE_DMA is used by defining ARCH_ZONE_DMA_BITS. Contains various fixes from Benjamin Herrenschmidt. Signed-off-by: Christoph Hellwig Signed-off-by: Michael Ellerman --- arch/powerpc/Kconfig | 8 ++--- arch/powerpc/include/asm/page.h | 2 ++ arch/powerpc/include/asm/pgtable.h | 1 - arch/powerpc/kernel/dma-swiotlb.c | 6 +--- arch/powerpc/kernel/dma.c | 8 ++--- arch/powerpc/mm/mem.c | 47 ++++++++++----------------- arch/powerpc/platforms/85xx/corenet_generic.c | 10 ------ arch/powerpc/platforms/85xx/qemu_e500.c | 9 ----- 8 files changed, 25 insertions(+), 66 deletions(-) (limited to 'arch/powerpc') diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index c446e377acd3..6d6e1ffdafba 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -375,9 +375,9 @@ config PPC_ADV_DEBUG_DAC_RANGE depends on PPC_ADV_DEBUG_REGS && 44x default y -config ZONE_DMA32 +config ZONE_DMA bool - default y if PPC64 + default y if PPC_BOOK3E_64 config PGTABLE_LEVELS int @@ -870,10 +870,6 @@ config ISA have an IBM RS/6000 or pSeries machine, say Y. If you have an embedded board, consult your board documentation. -config ZONE_DMA - bool - default y - config GENERIC_ISA_DMA bool depends on ISA_DMA_API diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h index a7624a3b1435..5c5ea2413413 100644 --- a/arch/powerpc/include/asm/page.h +++ b/arch/powerpc/include/asm/page.h @@ -340,4 +340,6 @@ struct vm_area_struct; #endif /* __ASSEMBLY__ */ #include +#define ARCH_ZONE_DMA_BITS 31 + #endif /* _ASM_POWERPC_PAGE_H */ diff --git a/arch/powerpc/include/asm/pgtable.h b/arch/powerpc/include/asm/pgtable.h index f2bfaf674674..dad1d27e196d 100644 --- a/arch/powerpc/include/asm/pgtable.h +++ b/arch/powerpc/include/asm/pgtable.h @@ -66,7 +66,6 @@ extern unsigned long empty_zero_page[]; extern pgd_t swapper_pg_dir[]; -void limit_zone_pfn(enum zone_type zone, unsigned long max_pfn); int dma_pfn_limit_to_zone(u64 pfn_limit); extern void paging_init(void); diff --git a/arch/powerpc/kernel/dma-swiotlb.c b/arch/powerpc/kernel/dma-swiotlb.c index 5fc335f4d9cd..678811abccfc 100644 --- a/arch/powerpc/kernel/dma-swiotlb.c +++ b/arch/powerpc/kernel/dma-swiotlb.c @@ -108,12 +108,8 @@ int __init swiotlb_setup_bus_notifier(void) void __init swiotlb_detect_4g(void) { - if ((memblock_end_of_DRAM() - 1) > 0xffffffff) { + if ((memblock_end_of_DRAM() - 1) > 0xffffffff) ppc_swiotlb_enable = 1; -#ifdef CONFIG_ZONE_DMA32 - limit_zone_pfn(ZONE_DMA32, (1ULL << 32) >> PAGE_SHIFT); -#endif - } } static int __init check_swiotlb_enabled(void) diff --git a/arch/powerpc/kernel/dma.c b/arch/powerpc/kernel/dma.c index e51ff967808c..b1903ebb2e9c 100644 --- a/arch/powerpc/kernel/dma.c +++ b/arch/powerpc/kernel/dma.c @@ -50,7 +50,8 @@ static int dma_nommu_dma_supported(struct device *dev, u64 mask) return 1; #ifdef CONFIG_FSL_SOC - /* Freescale gets another chance via ZONE_DMA/ZONE_DMA32, however + /* + * Freescale gets another chance via ZONE_DMA, however * that will have to be refined if/when they support iommus */ return 1; @@ -88,13 +89,10 @@ void *__dma_nommu_alloc_coherent(struct device *dev, size_t size, } switch (zone) { +#ifdef CONFIG_ZONE_DMA case ZONE_DMA: flag |= GFP_DMA; break; -#ifdef CONFIG_ZONE_DMA32 - case ZONE_DMA32: - flag |= GFP_DMA32; - break; #endif }; #endif /* CONFIG_FSL_SOC */ diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index 065c37d54b49..20394e52fe27 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -246,35 +246,19 @@ static int __init mark_nonram_nosave(void) } #endif -static bool zone_limits_final; - /* - * The memory zones past TOP_ZONE are managed by generic mm code. - * These should be set to zero since that's what every other - * architecture does. + * Zones usage: + * + * We setup ZONE_DMA to be 31-bits on all platforms and ZONE_NORMAL to be + * everything else. GFP_DMA32 page allocations automatically fall back to + * ZONE_DMA. + * + * By using 31-bit unconditionally, we can exploit ARCH_ZONE_DMA_BITS to + * inform the generic DMA mapping code. 32-bit only devices (if not handled + * by an IOMMU anyway) will take a first dip into ZONE_NORMAL and get + * otherwise served by ZONE_DMA. */ -static unsigned long max_zone_pfns[MAX_NR_ZONES] = { - [0 ... TOP_ZONE ] = ~0UL, - [TOP_ZONE + 1 ... MAX_NR_ZONES - 1] = 0 -}; - -/* - * Restrict the specified zone and all more restrictive zones - * to be below the specified pfn. May not be called after - * paging_init(). - */ -void __init limit_zone_pfn(enum zone_type zone, unsigned long pfn_limit) -{ - int i; - - if (WARN_ON(zone_limits_final)) - return; - - for (i = zone; i >= 0; i--) { - if (max_zone_pfns[i] > pfn_limit) - max_zone_pfns[i] = pfn_limit; - } -} +static unsigned long max_zone_pfns[MAX_NR_ZONES]; /* * Find the least restrictive zone that is entirely below the @@ -324,11 +308,14 @@ void __init paging_init(void) printk(KERN_DEBUG "Memory hole size: %ldMB\n", (long int)((top_of_ram - total_ram) >> 20)); +#ifdef CONFIG_ZONE_DMA + max_zone_pfns[ZONE_DMA] = min(max_low_pfn, 0x7fffffffUL >> PAGE_SHIFT); +#endif + max_zone_pfns[ZONE_NORMAL] = max_low_pfn; #ifdef CONFIG_HIGHMEM - limit_zone_pfn(ZONE_NORMAL, lowmem_end_addr >> PAGE_SHIFT); + max_zone_pfns[ZONE_HIGHMEM] = max_pfn; #endif - limit_zone_pfn(TOP_ZONE, top_of_ram >> PAGE_SHIFT); - zone_limits_final = true; + free_area_init_nodes(max_zone_pfns); mark_nonram_nosave(); diff --git a/arch/powerpc/platforms/85xx/corenet_generic.c b/arch/powerpc/platforms/85xx/corenet_generic.c index ac191a7a1337..b0dac307bebf 100644 --- a/arch/powerpc/platforms/85xx/corenet_generic.c +++ b/arch/powerpc/platforms/85xx/corenet_generic.c @@ -68,16 +68,6 @@ void __init corenet_gen_setup_arch(void) swiotlb_detect_4g(); -#if defined(CONFIG_FSL_PCI) && defined(CONFIG_ZONE_DMA32) - /* - * Inbound windows don't cover the full lower 4 GiB - * due to conflicts with PCICSRBAR and outbound windows, - * so limit the DMA32 zone to 2 GiB, to allow consistent - * allocations to succeed. - */ - limit_zone_pfn(ZONE_DMA32, 1UL << (31 - PAGE_SHIFT)); -#endif - pr_info("%s board\n", ppc_md.name); mpc85xx_qe_init(); diff --git a/arch/powerpc/platforms/85xx/qemu_e500.c b/arch/powerpc/platforms/85xx/qemu_e500.c index b63a8548366f..27631c607f3d 100644 --- a/arch/powerpc/platforms/85xx/qemu_e500.c +++ b/arch/powerpc/platforms/85xx/qemu_e500.c @@ -45,15 +45,6 @@ static void __init qemu_e500_setup_arch(void) fsl_pci_assign_primary(); swiotlb_detect_4g(); -#if defined(CONFIG_FSL_PCI) && defined(CONFIG_ZONE_DMA32) - /* - * Inbound windows don't cover the full lower 4 GiB - * due to conflicts with PCICSRBAR and outbound windows, - * so limit the DMA32 zone to 2 GiB, to allow consistent - * allocations to succeed. - */ - limit_zone_pfn(ZONE_DMA32, 1UL << (31 - PAGE_SHIFT)); -#endif mpc85xx_smp_init(); } -- cgit v1.2.3