On 2015/7/3 1:50, Liviu Dudau wrote: > On Wed, Jul 01, 2015 at 10:43:33AM +0100, Zhou Wang wrote: >> This patch had added by Arnd Bergmann during last reviewing of v1 patchset[1]. >> >> PCI core codes call pcibios_align_resource(). In ARM specific one, it will >> dereference pci_sys_data and call sys->align_resource. If we try to unify ARM >> and ARM64 PCIe API in pcie-designware. it will bring kernel crash when run into >> this dereferencing. >> >> However, in ARM there is only pci-mvebu which implements align_resource. So >> add align_resource call back in pci_host_bridge structure and override >> pcibios_align_resource with it. >> >> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> >> Signed-off-by: Zhou Wang <wangzhou1@xxxxxxxxxxxxx> >> Tested-by: Fabrice Gasnier <fabrice.gasnier@xxxxxx> >> >> [1] http://www.spinics.net/lists/linux-pci/msg41671.html >> --- >> arch/arm/kernel/bios32.c | 6 ------ >> drivers/pci/host/pci-mvebu.c | 47 ++++++++++++++++++++++++++++---------------- >> drivers/pci/setup-res.c | 27 ++++++++++++++++++++----- >> include/linux/pci.h | 3 +++ >> 4 files changed, 55 insertions(+), 28 deletions(-) >> >> diff --git a/arch/arm/kernel/bios32.c b/arch/arm/kernel/bios32.c >> index fcbbbb1..b01189f 100644 >> --- a/arch/arm/kernel/bios32.c >> +++ b/arch/arm/kernel/bios32.c >> @@ -468,7 +468,6 @@ static void pcibios_init_hw(struct device *parent, struct hw_pci *hw, >> sys->busnr = busnr; >> sys->swizzle = hw->swizzle; >> sys->map_irq = hw->map_irq; >> - sys->align_resource = hw->align_resource; >> INIT_LIST_HEAD(&sys->resources); >> >> if (hw->private_data) >> @@ -588,8 +587,6 @@ char * __init pcibios_setup(char *str) >> resource_size_t pcibios_align_resource(void *data, const struct resource *res, >> resource_size_t size, resource_size_t align) >> { >> - struct pci_dev *dev = data; >> - struct pci_sys_data *sys = dev->sysdata; >> resource_size_t start = res->start; >> >> if (res->flags & IORESOURCE_IO && start & 0x300) >> @@ -597,9 +594,6 @@ resource_size_t pcibios_align_resource(void *data, const struct resource *res, >> >> start = (start + align - 1) & ~(align - 1); >> >> - if (sys->align_resource) >> - return sys->align_resource(dev, res, start, size, align); >> - >> return start; >> } >> >> diff --git a/drivers/pci/host/pci-mvebu.c b/drivers/pci/host/pci-mvebu.c >> index 1ab8635..155d05f 100644 >> --- a/drivers/pci/host/pci-mvebu.c >> +++ b/drivers/pci/host/pci-mvebu.c >> @@ -22,6 +22,8 @@ >> #include <linux/of_pci.h> >> #include <linux/of_platform.h> >> >> +#include "../pci.h" /* HACK to see pci_find_host_bridge */ >> + >> /* >> * PCIe unit register offsets. >> */ >> @@ -751,27 +753,20 @@ static int mvebu_pcie_setup(int nr, struct pci_sys_data *sys) >> return 1; >> } >> >> -static struct pci_bus *mvebu_pcie_scan_bus(int nr, struct pci_sys_data *sys) >> +static resource_size_t mvebu_pcie_align_resource(void *data, >> + const struct resource *res, >> + resource_size_t size, >> + resource_size_t align) >> { >> - struct mvebu_pcie *pcie = sys_to_pcie(sys); >> - struct pci_bus *bus; >> + struct pci_dev *dev = data; >> >> - bus = pci_create_root_bus(&pcie->pdev->dev, sys->busnr, >> - &mvebu_pcie_ops, sys, &sys->resources); >> - if (!bus) >> - return NULL; >> + resource_size_t start = res->start; >> >> - pci_scan_child_bus(bus); >> + if (res->flags & IORESOURCE_IO && start & 0x300) >> + start = (start + 0x3ff) & ~0x3ff; >> >> - return bus; >> -} >> + start = (start + align - 1) & ~(align - 1); > > Honestly, I don't see here anything that is mvebu specific. Could you move What I mean is that there is only mvebu who implemented sys->align_resource callback in ARM arch. > this function in the generic pci/host area and have a flag in the pci_host_bridge > structure whether the function should be called or not? I know that in a way > that looks very close to the existing implementation which uses pcibios_align_resource, I am confused about "the existing implementation". Now pcibios_align_resource are implemented by each arch code and are called directly. Did I miss anything about pcibios_align_resource? Best rgards, Zhou > but the problem with pcibios_ version is that it is arch specific and not driver > specific the way we want. > > Having this version as a generic implementation would also remove at least 2 more > arch version, possibly more after testing by the arch maintainers. > > Best regards, > Liviu > >> >> -static resource_size_t mvebu_pcie_align_resource(struct pci_dev *dev, >> - const struct resource *res, >> - resource_size_t start, >> - resource_size_t size, >> - resource_size_t align) >> -{ >> if (dev->bus->number != 0) >> return start; >> >> @@ -796,6 +791,25 @@ static resource_size_t mvebu_pcie_align_resource(struct pci_dev *dev, >> return start; >> } >> >> +static struct pci_bus *mvebu_pcie_scan_bus(int nr, struct pci_sys_data *sys) >> +{ >> + struct mvebu_pcie *pcie = sys_to_pcie(sys); >> + struct pci_host_bridge *phb; >> + struct pci_bus *bus; >> + >> + bus = pci_create_root_bus(&pcie->pdev->dev, sys->busnr, >> + &mvebu_pcie_ops, sys, &sys->resources); >> + if (!bus) >> + return NULL; >> + >> + phb = pci_find_host_bridge(bus); >> + phb->align_resource = mvebu_pcie_align_resource; >> + >> + pci_scan_child_bus(bus); >> + >> + return bus; >> +} >> + >> static void mvebu_pcie_enable(struct mvebu_pcie *pcie) >> { >> struct hw_pci hw; >> @@ -812,7 +826,6 @@ static void mvebu_pcie_enable(struct mvebu_pcie *pcie) >> hw.scan = mvebu_pcie_scan_bus; >> hw.map_irq = of_irq_parse_and_map_pci; >> hw.ops = &mvebu_pcie_ops; >> - hw.align_resource = mvebu_pcie_align_resource; >> >> pci_common_init(&hw); >> } >> diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c >> index 232f925..73abca7 100644 >> --- a/drivers/pci/setup-res.c >> +++ b/drivers/pci/setup-res.c >> @@ -200,7 +200,11 @@ static int pci_revert_fw_address(struct resource *res, struct pci_dev *dev, >> } >> >> static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev, >> - int resno, resource_size_t size, resource_size_t align) >> + int resno, resource_size_t size, resource_size_t align, >> + resource_size_t (*alignf)(void *, >> + const struct resource *, >> + resource_size_t, >> + resource_size_t)) >> { >> struct resource *res = dev->resource + resno; >> resource_size_t min; >> @@ -217,7 +221,7 @@ static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev, >> */ >> ret = pci_bus_alloc_resource(bus, res, size, align, min, >> IORESOURCE_PREFETCH | IORESOURCE_MEM_64, >> - pcibios_align_resource, dev); >> + alignf, dev); >> if (ret == 0) >> return 0; >> >> @@ -229,7 +233,7 @@ static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev, >> (IORESOURCE_PREFETCH | IORESOURCE_MEM_64)) { >> ret = pci_bus_alloc_resource(bus, res, size, align, min, >> IORESOURCE_PREFETCH, >> - pcibios_align_resource, dev); >> + alignf, dev); >> if (ret == 0) >> return 0; >> } >> @@ -242,7 +246,7 @@ static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev, >> */ >> if (res->flags & (IORESOURCE_PREFETCH | IORESOURCE_MEM_64)) >> ret = pci_bus_alloc_resource(bus, res, size, align, min, 0, >> - pcibios_align_resource, dev); >> + alignf, dev); >> >> return ret; >> } >> @@ -251,10 +255,23 @@ static int _pci_assign_resource(struct pci_dev *dev, int resno, >> resource_size_t size, resource_size_t min_align) >> { >> struct pci_bus *bus; >> + struct pci_host_bridge *phb; >> + resource_size_t (*alignf)(void *, >> + const struct resource *, >> + resource_size_t, >> + resource_size_t); >> int ret; >> >> bus = dev->bus; >> - while ((ret = __pci_assign_resource(bus, dev, resno, size, min_align))) { >> + phb = pci_find_host_bridge(bus); >> + >> + if (phb->align_resource) >> + alignf = phb->align_resource; >> + else >> + alignf = pcibios_align_resource; >> + >> + while ((ret = __pci_assign_resource(bus, dev, resno, size, >> + min_align, alignf))) { >> if (!bus->parent || !bus->self->transparent) >> break; >> bus = bus->parent; >> diff --git a/include/linux/pci.h b/include/linux/pci.h >> index 353db8d..39e48fc 100644 >> --- a/include/linux/pci.h >> +++ b/include/linux/pci.h >> @@ -404,6 +404,9 @@ struct pci_host_bridge { >> struct device dev; >> struct pci_bus *bus; /* root bus */ >> struct list_head windows; /* resource_entry */ >> + resource_size_t (*align_resource)(void *data, >> + const struct resource *res, >> + resource_size_t size, resource_size_t align); >> void (*release_fn)(struct pci_host_bridge *); >> void *release_data; >> unsigned int ignore_reset_delay:1; /* for entire hierarchy */ >> -- >> 1.9.1 >> > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
