On Tue, Jul 07, 2015 at 06:44:01AM +0100, Zhou Wang wrote: > 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? Sorry, I meant existing implementation_s_ and yes, I was reffering to the arch specific code. If you look at the cris, frv/mb93090-mb00, m68k, microblaze, powerpc, unicore32 and x86 they all share the code with your version, plus or minus additional checks. I was thinking that for those arch versions that match your version you can create just one version and use it as the alignf function. Best regards, Liviu > > 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 linux-pci" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- ==================== | I would like to | | fix the world, | | but they're not | | giving me the | \ source code! / --------------- ¯\_(ツ)_/¯ -- 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
