From e380a0394c36a3a878c858418d5dd7f5f195b6fc Mon Sep 17 00:00:00 2001 From: Nicolas Saenz Julienne Date: Thu, 7 Nov 2019 16:06:45 +0100 Subject: x86/PCI: sta2x11: use default DMA address translation The devices found behind this PCIe chip have unusual DMA mapping constraints as there is an AMBA interconnect placed in between them and the different PCI endpoints. The offset between physical memory addresses and AMBA's view is provided by reading a PCI config register, which is saved and used whenever DMA mapping is needed. It turns out that this DMA setup can be represented by properly setting 'dma_pfn_offset', 'dma_bus_mask' and 'dma_mask' during the PCI device enable fixup. And ultimately allows us to get rid of this device's custom DMA functions. Aside from the code deletion and DMA setup, sta2x11_pdev_to_mapping() is moved to avoid warnings whenever CONFIG_PM is not enabled. Signed-off-by: Nicolas Saenz Julienne Signed-off-by: Christoph Hellwig --- arch/x86/Kconfig | 1 - arch/x86/include/asm/device.h | 3 - arch/x86/include/asm/dma-direct.h | 9 --- arch/x86/pci/sta2x11-fixup.c | 135 ++++++++------------------------------ 4 files changed, 26 insertions(+), 122 deletions(-) delete mode 100644 arch/x86/include/asm/dma-direct.h (limited to 'arch/x86') diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index d6e1faa28c58..35dd8f147f99 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -708,7 +708,6 @@ config X86_SUPPORTS_MEMORY_FAILURE config STA2X11 bool "STA2X11 Companion Chip Support" depends on X86_32_NON_STANDARD && PCI - select ARCH_HAS_PHYS_TO_DMA select SWIOTLB select MFD_STA2X11 select GPIOLIB diff --git a/arch/x86/include/asm/device.h b/arch/x86/include/asm/device.h index a8f6c809d9b1..5e12c63b47aa 100644 --- a/arch/x86/include/asm/device.h +++ b/arch/x86/include/asm/device.h @@ -6,9 +6,6 @@ struct dev_archdata { #if defined(CONFIG_INTEL_IOMMU) || defined(CONFIG_AMD_IOMMU) void *iommu; /* hook for IOMMU specific extension */ #endif -#ifdef CONFIG_STA2X11 - bool is_sta2x11; -#endif }; #if defined(CONFIG_X86_DEV_DMA_OPS) && defined(CONFIG_PCI_DOMAINS) diff --git a/arch/x86/include/asm/dma-direct.h b/arch/x86/include/asm/dma-direct.h deleted file mode 100644 index 1a19251eaac9..000000000000 --- a/arch/x86/include/asm/dma-direct.h +++ /dev/null @@ -1,9 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -#ifndef ASM_X86_DMA_DIRECT_H -#define ASM_X86_DMA_DIRECT_H 1 - -bool dma_capable(struct device *dev, dma_addr_t addr, size_t size); -dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr); -phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t daddr); - -#endif /* ASM_X86_DMA_DIRECT_H */ diff --git a/arch/x86/pci/sta2x11-fixup.c b/arch/x86/pci/sta2x11-fixup.c index 6269a175385d..4a631264b809 100644 --- a/arch/x86/pci/sta2x11-fixup.c +++ b/arch/x86/pci/sta2x11-fixup.c @@ -30,7 +30,6 @@ struct sta2x11_ahb_regs { /* saved during suspend */ }; struct sta2x11_mapping { - u32 amba_base; int is_suspended; struct sta2x11_ahb_regs regs[STA2X11_NR_FUNCS]; }; @@ -92,18 +91,6 @@ static int sta2x11_pdev_to_ep(struct pci_dev *pdev) return pdev->bus->number - instance->bus0; } -static struct sta2x11_mapping *sta2x11_pdev_to_mapping(struct pci_dev *pdev) -{ - struct sta2x11_instance *instance; - int ep; - - instance = sta2x11_pdev_to_instance(pdev); - if (!instance) - return NULL; - ep = sta2x11_pdev_to_ep(pdev); - return instance->map + ep; -} - /* This is exported, as some devices need to access the MFD registers */ struct sta2x11_instance *sta2x11_get_instance(struct pci_dev *pdev) { @@ -111,39 +98,6 @@ struct sta2x11_instance *sta2x11_get_instance(struct pci_dev *pdev) } EXPORT_SYMBOL(sta2x11_get_instance); - -/** - * p2a - Translate physical address to STA2x11 AMBA address, - * used for DMA transfers to STA2x11 - * @p: Physical address - * @pdev: PCI device (must be hosted within the connext) - */ -static dma_addr_t p2a(dma_addr_t p, struct pci_dev *pdev) -{ - struct sta2x11_mapping *map; - dma_addr_t a; - - map = sta2x11_pdev_to_mapping(pdev); - a = p + map->amba_base; - return a; -} - -/** - * a2p - Translate STA2x11 AMBA address to physical address - * used for DMA transfers from STA2x11 - * @a: STA2x11 AMBA address - * @pdev: PCI device (must be hosted within the connext) - */ -static dma_addr_t a2p(dma_addr_t a, struct pci_dev *pdev) -{ - struct sta2x11_mapping *map; - dma_addr_t p; - - map = sta2x11_pdev_to_mapping(pdev); - p = a - map->amba_base; - return p; -} - /* At setup time, we use our own ops if the device is a ConneXt one */ static void sta2x11_setup_pdev(struct pci_dev *pdev) { @@ -151,70 +105,12 @@ static void sta2x11_setup_pdev(struct pci_dev *pdev) if (!instance) /* either a sta2x11 bridge or another ST device */ return; - pci_set_consistent_dma_mask(pdev, STA2X11_AMBA_SIZE - 1); - pci_set_dma_mask(pdev, STA2X11_AMBA_SIZE - 1); - pdev->dev.archdata.is_sta2x11 = true; /* We must enable all devices as master, for audio DMA to work */ pci_set_master(pdev); } DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, sta2x11_setup_pdev); -/* - * The following three functions are exported (used in swiotlb: FIXME) - */ -/** - * dma_capable - Check if device can manage DMA transfers (FIXME: kill it) - * @dev: device for a PCI device - * @addr: DMA address - * @size: DMA size - */ -bool dma_capable(struct device *dev, dma_addr_t addr, size_t size) -{ - struct sta2x11_mapping *map; - - if (!dev->archdata.is_sta2x11) { - if (!dev->dma_mask) - return false; - return addr + size - 1 <= *dev->dma_mask; - } - - map = sta2x11_pdev_to_mapping(to_pci_dev(dev)); - - if (!map || (addr < map->amba_base)) - return false; - if (addr + size >= map->amba_base + STA2X11_AMBA_SIZE) { - return false; - } - - return true; -} - -/** - * __phys_to_dma - Return the DMA AMBA address used for this STA2x11 device - * @dev: device for a PCI device - * @paddr: Physical address - */ -dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr) -{ - if (!dev->archdata.is_sta2x11) - return paddr; - return p2a(paddr, to_pci_dev(dev)); -} - -/** - * dma_to_phys - Return the physical address used for this STA2x11 DMA address - * @dev: device for a PCI device - * @daddr: STA2x11 AMBA DMA address - */ -phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t daddr) -{ - if (!dev->archdata.is_sta2x11) - return daddr; - return a2p(daddr, to_pci_dev(dev)); -} - - /* * At boot we must set up the mappings for the pcie-to-amba bridge. * It involves device access, and the same happens at suspend/resume time @@ -234,12 +130,22 @@ phys_addr_t __dma_to_phys(struct device *dev, dma_addr_t daddr) /* At probe time, enable mapping for each endpoint, using the pdev */ static void sta2x11_map_ep(struct pci_dev *pdev) { - struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev); + struct sta2x11_instance *instance = sta2x11_pdev_to_instance(pdev); + struct device *dev = &pdev->dev; + u32 amba_base, max_amba_addr; int i; - if (!map) + if (!instance) return; - pci_read_config_dword(pdev, AHB_BASE(0), &map->amba_base); + + pci_read_config_dword(pdev, AHB_BASE(0), &amba_base); + max_amba_addr = amba_base + STA2X11_AMBA_SIZE - 1; + + dev->dma_pfn_offset = PFN_DOWN(-amba_base); + + dev->bus_dma_mask = max_amba_addr; + pci_set_consistent_dma_mask(pdev, max_amba_addr); + pci_set_dma_mask(pdev, max_amba_addr); /* Configure AHB mapping */ pci_write_config_dword(pdev, AHB_PEXLBASE(0), 0); @@ -253,13 +159,24 @@ static void sta2x11_map_ep(struct pci_dev *pdev) dev_info(&pdev->dev, "sta2x11: Map EP %i: AMBA address %#8x-%#8x\n", - sta2x11_pdev_to_ep(pdev), map->amba_base, - map->amba_base + STA2X11_AMBA_SIZE - 1); + sta2x11_pdev_to_ep(pdev), amba_base, max_amba_addr); } DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, sta2x11_map_ep); #ifdef CONFIG_PM /* Some register values must be saved and restored */ +static struct sta2x11_mapping *sta2x11_pdev_to_mapping(struct pci_dev *pdev) +{ + struct sta2x11_instance *instance; + int ep; + + instance = sta2x11_pdev_to_instance(pdev); + if (!instance) + return NULL; + ep = sta2x11_pdev_to_ep(pdev); + return instance->map + ep; +} + static void suspend_mapping(struct pci_dev *pdev) { struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev); -- cgit v1.2.3 From 68a33b1794665ba8a1d1ef1d3bfcc7c587d380a6 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 19 Nov 2019 17:38:58 +0100 Subject: dma-direct: exclude dma_direct_map_resource from the min_low_pfn check The valid memory address check in dma_capable only makes sense when mapping normal memory, not when using dma_map_resource to map a device resource. Add a new boolean argument to dma_capable to exclude that check for the dma_map_resource case. Fixes: b12d66278dd6 ("dma-direct: check for overflows on 32 bit DMA addresses") Reported-by: Marek Szyprowski Signed-off-by: Christoph Hellwig Acked-by: Marek Szyprowski Tested-by: Marek Szyprowski --- arch/x86/kernel/amd_gart_64.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/kernel/amd_gart_64.c b/arch/x86/kernel/amd_gart_64.c index a6ac3712db8b..5cfab41e8509 100644 --- a/arch/x86/kernel/amd_gart_64.c +++ b/arch/x86/kernel/amd_gart_64.c @@ -185,13 +185,13 @@ static void iommu_full(struct device *dev, size_t size, int dir) static inline int need_iommu(struct device *dev, unsigned long addr, size_t size) { - return force_iommu || !dma_capable(dev, addr, size); + return force_iommu || !dma_capable(dev, addr, size, true); } static inline int nonforced_iommu(struct device *dev, unsigned long addr, size_t size) { - return !dma_capable(dev, addr, size); + return !dma_capable(dev, addr, size, true); } /* Map a single continuous physical area into the IOMMU. -- cgit v1.2.3 From a7ba70f1787f977f970cd116076c6fce4b9e01cc Mon Sep 17 00:00:00 2001 From: Nicolas Saenz Julienne Date: Thu, 21 Nov 2019 10:26:44 +0100 Subject: dma-mapping: treat dev->bus_dma_mask as a DMA limit Using a mask to represent bus DMA constraints has a set of limitations. The biggest one being it can only hold a power of two (minus one). The DMA mapping code is already aware of this and treats dev->bus_dma_mask as a limit. This quirk is already used by some architectures although still rare. With the introduction of the Raspberry Pi 4 we've found a new contender for the use of bus DMA limits, as its PCIe bus can only address the lower 3GB of memory (of a total of 4GB). This is impossible to represent with a mask. To make things worse the device-tree code rounds non power of two bus DMA limits to the next power of two, which is unacceptable in this case. In the light of this, rename dev->bus_dma_mask to dev->bus_dma_limit all over the tree and treat it as such. Note that dev->bus_dma_limit should contain the higher accessible DMA address. Signed-off-by: Nicolas Saenz Julienne Reviewed-by: Robin Murphy Signed-off-by: Christoph Hellwig --- arch/x86/kernel/pci-dma.c | 2 +- arch/x86/mm/mem_encrypt.c | 2 +- arch/x86/pci/sta2x11-fixup.c | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c index fa4352dce491..3a75d665d43c 100644 --- a/arch/x86/kernel/pci-dma.c +++ b/arch/x86/kernel/pci-dma.c @@ -146,7 +146,7 @@ rootfs_initcall(pci_iommu_init); static int via_no_dac_cb(struct pci_dev *pdev, void *data) { - pdev->dev.bus_dma_mask = DMA_BIT_MASK(32); + pdev->dev.bus_dma_limit = DMA_BIT_MASK(32); return 0; } diff --git a/arch/x86/mm/mem_encrypt.c b/arch/x86/mm/mem_encrypt.c index 9268c12458c8..a03614bd3e1a 100644 --- a/arch/x86/mm/mem_encrypt.c +++ b/arch/x86/mm/mem_encrypt.c @@ -367,7 +367,7 @@ bool force_dma_unencrypted(struct device *dev) if (sme_active()) { u64 dma_enc_mask = DMA_BIT_MASK(__ffs64(sme_me_mask)); u64 dma_dev_mask = min_not_zero(dev->coherent_dma_mask, - dev->bus_dma_mask); + dev->bus_dma_limit); if (dma_dev_mask <= dma_enc_mask) return true; diff --git a/arch/x86/pci/sta2x11-fixup.c b/arch/x86/pci/sta2x11-fixup.c index 4a631264b809..c313d784efab 100644 --- a/arch/x86/pci/sta2x11-fixup.c +++ b/arch/x86/pci/sta2x11-fixup.c @@ -143,7 +143,7 @@ static void sta2x11_map_ep(struct pci_dev *pdev) dev->dma_pfn_offset = PFN_DOWN(-amba_base); - dev->bus_dma_mask = max_amba_addr; + dev->bus_dma_limit = max_amba_addr; pci_set_consistent_dma_mask(pdev, max_amba_addr); pci_set_dma_mask(pdev, max_amba_addr); -- cgit v1.2.3