[RFC PATCH v1 1/3] PCI: designware: Add ARM64 support
Zhou Wang
wangzhou1 at hisilicon.com
Thu May 28 04:48:37 PDT 2015
On 2015/5/28 3:51, Arnd Bergmann wrote:
> On Wednesday 27 May 2015 18:19:57 Fabrice Gasnier wrote:
>> On 05/27/2015 05:43 PM, Arnd Bergmann wrote:
>>> On Wednesday 27 May 2015 17:31:46 Arnd Bergmann wrote:
>>>> Yes, that works. However there are two problems with the approach:
>>>>
>>>> - we have to change all PCI host drivers on ARM to do this in order to remove
>>>> the ARM-specific pcibios_msi_controller() function
>>>> - it's possible that there are dw_pcie implementations that do not include
>>>> an MSI controller, so that pointer would be NULL, which leads to the
>>>> core code to still call the ARM-specific pcibios_msi_controller() function
>>>> unless we remove it.
>>> I wonder if this simple patch would be sufficient to kill off
>>> pcibios_msi_controller().
>>>
>>> Can one of you try it?
>>>
>>> Arnd
>>
>> Hi Arnd,
>> I tested it quickly on my platform, with and without CONFIG_PCI_MSI.
>> In both case it seems to run fine with dw pcie.
>>
>
> Awesome. Now we just need to find a way to move the align_resource callback.
> I wonder if the approach below would be acceptable.
>
> Arnd
>
Hi Arnd,
Many thanks for your kindly suggestions.
> diff --git a/arch/arm/kernel/bios32.c b/arch/arm/kernel/bios32.c
> index fcbbbb1b9e95..20839d26a490 100644
> --- a/arch/arm/kernel/bios32.c
> +++ b/arch/arm/kernel/bios32.c
> @@ -597,9 +588,6 @@ 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 1ab863551920..74216c9c2822 100644
> --- a/drivers/pci/host/pci-mvebu.c
> +++ b/drivers/pci/host/pci-mvebu.c
> @@ -751,27 +751,20 @@ 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 device *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);
>
> -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 +789,25 @@ 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 +824,6 @@ 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 232f9254c11a..e1f5e13c4636 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 +255,19 @@ 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;
> 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;
>
I think this code is fine, and we also should add a funtion point in struct pci_host_bridge to
store mvebu_pcie_align_resource. How about I make a new version patchset with above codes for
further reviewing ?
Best Regards,
Zhou
>
> .
>
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