[PATCH v3 2/2] ARM: pci: kill pcibios_msi_controller
Jingoo Han
jingoohan1 at gmail.com
Wed Jul 29 01:32:01 PDT 2015
On 2015. 7. 28., at PM 7:32, Lorenzo Pieralisi <lorenzo.pieralisi at arm.com> wrote:
>
> On ARM PCI systems relying on the pcibios API to initialize PCI host
> controllers, the pcibios_msi_controller weak callback is used to look-up
> the msi_controller pointer, through pci_sys_data msi_ctrl pointer.
>
> pci_sys_data is an ARM specific structure, which prevents using the
> same mechanism (so same PCI host controller drivers) on ARM64 systems.
>
> Since the struct pci_bus already contains an msi_controller pointer and
> the kernel already uses it to look-up the msi controller,
> this patch converts ARM host controller and related pcibios/host bridges
> initialization routines so that the msi_controller pointer look-up can be
> carried out by PCI core code through the struct pci_bus msi pointer,
> removing the need for the arch specific pcibios_msi_controller callback
> and the related pci_sys_data msi_ctrl pointer.
>
> To simplify the conversion, this patch adds a new function in PCI
> core code (pci_scan_root_bus_msi()) that takes the msi_controller
> pointer as an additional parameter wrt pci_scan_root_bus() so that
> the msi controller pointer can be effectively propagated at probe time
> through the augmented API.
>
> The existing pci_scan_root_bus() API is made to rely on the newly
> introduced function, by passing a NULL msi pointer to it so
> that it can be used when no msi controller pointer passing is required
> without additional code (and API conversions) in the core PCI layer.
>
> ARM is the only arch relying on the pcibios_msi_controller() weak
> function, hence this patch also removes its default weak implementation
> from PCI core code since it becomes of no use.
>
> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi at arm.com>
> Suggested-by: Russell King <linux at arm.linux.org.uk>
> Acked-by: Marc Zyngier <marc.zyngier at arm.com>
> Cc: Pratyush Anand <pratyush.anand at gmail.com>
> Cc: Arnd Bergmann <arnd at arndb.de>
> Cc: Jingoo Han <jingoohan1 at gmail.com>
> Cc: Bjorn Helgaas <bhelgaas at google.com>
> Cc: Simon Horman <horms at verge.net.au>
> Cc: Russell King <linux at arm.linux.org.uk>
> Cc: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>
> Cc: Thierry Reding <thierry.reding at gmail.com>
> Cc: Michal Simek <michal.simek at xilinx.com>
> Cc: Marc Zyngier <marc.zyngier at arm.com>
> ---
> v2->v3
>
> - Added pci_scan_root_bus_msi() in core PCI code and converted ARM bios32 to
> use it
>
> v2: http://lists.infradead.org/pipermail/linux-arm-kernel/2015-July/359183.html
>
> v1->v2
>
> - Added patch to replace panic statements with WARN
> - Removed unused pcibios_msi_controller() and pci_msi_controller() from
> core code
> - Dropped RFT status
>
> v1: http://lists.infradead.org/pipermail/linux-arm-kernel/2015-July/356028.html
>
> arch/arm/include/asm/mach/pci.h | 5 -----
> arch/arm/kernel/bios32.c | 17 +++--------------
> drivers/pci/host/pcie-designware.c | 9 +++++++--
> drivers/pci/host/pcie-xilinx.c | 12 ++++++++++--
> drivers/pci/msi.c | 17 +----------------
> drivers/pci/probe.c | 15 +++++++++++++--
> include/linux/pci.h | 4 ++++
> 7 files changed, 38 insertions(+), 41 deletions(-)
>
> diff --git a/arch/arm/include/asm/mach/pci.h b/arch/arm/include/asm/mach/pci.h
> index 28b9bb3..8857d28 100644
> --- a/arch/arm/include/asm/mach/pci.h
> +++ b/arch/arm/include/asm/mach/pci.h
> @@ -19,9 +19,7 @@ struct pci_bus;
> struct device;
>
> struct hw_pci {
> -#ifdef CONFIG_PCI_MSI
> struct msi_controller *msi_ctrl;
> -#endif
> struct pci_ops *ops;
> int nr_controllers;
> void **private_data;
> @@ -42,9 +40,6 @@ struct hw_pci {
> * Per-controller structure
> */
> struct pci_sys_data {
> -#ifdef CONFIG_PCI_MSI
> - struct msi_controller *msi_ctrl;
> -#endif
> struct list_head node;
> int busnr; /* primary bus number */
> u64 mem_offset; /* bus->cpu memory mapping offset */
> diff --git a/arch/arm/kernel/bios32.c b/arch/arm/kernel/bios32.c
> index a5c782c..1a20076 100644
> --- a/arch/arm/kernel/bios32.c
> +++ b/arch/arm/kernel/bios32.c
> @@ -18,15 +18,6 @@
>
> static int debug_pci;
>
> -#ifdef CONFIG_PCI_MSI
> -struct msi_controller *pcibios_msi_controller(struct pci_dev *dev)
> -{
> - struct pci_sys_data *sysdata = dev->bus->sysdata;
> -
> - return sysdata->msi_ctrl;
> -}
> -#endif
> -
> /*
> * We can't use pci_get_device() here since we are
> * called from interrupt context.
> @@ -462,9 +453,6 @@ static void pcibios_init_hw(struct device *parent, struct hw_pci *hw,
> if (WARN(!sys, "PCI: unable to allocate sys data!"))
> break;
>
> -#ifdef CONFIG_PCI_MSI
> - sys->msi_ctrl = hw->msi_ctrl;
> -#endif
> sys->busnr = busnr;
> sys->swizzle = hw->swizzle;
> sys->map_irq = hw->map_irq;
> @@ -486,8 +474,9 @@ static void pcibios_init_hw(struct device *parent, struct hw_pci *hw,
> if (hw->scan)
> sys->bus = hw->scan(nr, sys);
> else
> - sys->bus = pci_scan_root_bus(parent, sys->busnr,
> - hw->ops, sys, &sys->resources);
> + sys->bus = pci_scan_root_bus_msi(parent,
> + sys->busnr, hw->ops, sys,
> + &sys->resources, hw->msi_ctrl);
>
> if (WARN(!sys->bus, "PCI: unable to scan bus!")) {
> kfree(sys);
> diff --git a/drivers/pci/host/pcie-designware.c b/drivers/pci/host/pcie-designware.c
> index 69486be..e584dfa 100644
> --- a/drivers/pci/host/pcie-designware.c
> +++ b/drivers/pci/host/pcie-designware.c
> @@ -526,7 +526,6 @@ int dw_pcie_host_init(struct pcie_port *pp)
>
> #ifdef CONFIG_PCI_MSI
> dw_pcie_msi_chip.dev = pp->dev;
> - dw_pci.msi_ctrl = &dw_pcie_msi_chip;
> #endif
>
> dw_pci.nr_controllers = 1;
> @@ -708,11 +707,17 @@ static struct pci_bus *dw_pcie_scan_bus(int nr, struct pci_sys_data *sys)
> struct pcie_port *pp = sys_to_pcie(sys);
>
> pp->root_bus_nr = sys->busnr;
> - bus = pci_scan_root_bus(pp->dev, sys->busnr,
> + bus = pci_create_root_bus(pp->dev, sys->busnr,
> &dw_pcie_ops, sys, &sys->resources);
How about using pci_scan_root_bus_msi()?
This is because
pci_scan_root_bus_msi() adds the msi_controller to pci_bus.
Thus, adding msi_controller and calling pci_scan_child_bus() is not necessary
when pci_scan_root_bus_msi() is called here.
If I am wrong, please let me know kindly. Thank you.
Best regards,
Jingoo Han
> if (!bus)
> return NULL;
>
> +#ifdef CONFIG_PCI_MSI
> + bus->msi = &dw_pcie_msi_chip;
> +#endif
> +
> + pci_scan_child_bus(bus);
> +
> if (bus && pp->ops->scan_bus)
> pp->ops->scan_bus(pp);
>
> diff --git a/drivers/pci/host/pcie-xilinx.c b/drivers/pci/host/pcie-xilinx.c
> index f1a06a0..b21eb7d 100644
> --- a/drivers/pci/host/pcie-xilinx.c
> +++ b/drivers/pci/host/pcie-xilinx.c
> @@ -647,9 +647,18 @@ static struct pci_bus *xilinx_pcie_scan_bus(int nr, struct pci_sys_data *sys)
> struct pci_bus *bus;
>
> port->root_busno = sys->busnr;
> - bus = pci_scan_root_bus(port->dev, sys->busnr, &xilinx_pcie_ops,
> + bus = pci_create_root_bus(port->dev, sys->busnr, &xilinx_pcie_ops,
> sys, &sys->resources);
>
> + if (!bus)
> + return NULL;
> +
> +#ifdef CONFIG_PCI_MSI
> + bus->msi = &xilinx_pcie_msi_chip;
> +#endif
> +
> + pci_scan_child_bus(bus);
> +
> return bus;
> }
>
> @@ -847,7 +856,6 @@ static int xilinx_pcie_probe(struct platform_device *pdev)
>
> #ifdef CONFIG_PCI_MSI
> xilinx_pcie_msi_chip.dev = port->dev;
> - hw.msi_ctrl = &xilinx_pcie_msi_chip;
> #endif
> pci_common_init_dev(dev, &hw);
>
> diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
> index f66be86..0d20142 100644
> --- a/drivers/pci/msi.c
> +++ b/drivers/pci/msi.c
> @@ -77,24 +77,9 @@ static void pci_msi_teardown_msi_irqs(struct pci_dev *dev)
>
> /* Arch hooks */
>
> -struct msi_controller * __weak pcibios_msi_controller(struct pci_dev *dev)
> -{
> - return NULL;
> -}
> -
> -static struct msi_controller *pci_msi_controller(struct pci_dev *dev)
> -{
> - struct msi_controller *msi_ctrl = dev->bus->msi;
> -
> - if (msi_ctrl)
> - return msi_ctrl;
> -
> - return pcibios_msi_controller(dev);
> -}
> -
> int __weak arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)
> {
> - struct msi_controller *chip = pci_msi_controller(dev);
> + struct msi_controller *chip = dev->bus->msi;
> int err;
>
> if (!chip || !chip->setup_irq)
> diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
> index cefd636..4915c6d 100644
> --- a/drivers/pci/probe.c
> +++ b/drivers/pci/probe.c
> @@ -2096,8 +2096,9 @@ void pci_bus_release_busn_res(struct pci_bus *b)
> res, ret ? "can not be" : "is");
> }
>
> -struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
> - struct pci_ops *ops, void *sysdata, struct list_head *resources)
> +struct pci_bus *pci_scan_root_bus_msi(struct device *parent, int bus,
> + struct pci_ops *ops, void *sysdata,
> + struct list_head *resources, struct msi_controller *msi)
> {
> struct resource_entry *window;
> bool found = false;
> @@ -2114,6 +2115,8 @@ struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
> if (!b)
> return NULL;
>
> + b->msi = msi;
> +
> if (!found) {
> dev_info(&b->dev,
> "No busn resource found for root bus, will use [bus %02x-ff]\n",
> @@ -2128,6 +2131,14 @@ struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
>
> return b;
> }
> +EXPORT_SYMBOL(pci_scan_root_bus_msi);
> +
> +struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
> + struct pci_ops *ops, void *sysdata, struct list_head *resources)
> +{
> + return pci_scan_root_bus_msi(parent, bus, ops, sysdata, resources,
> + NULL);
> +}
> EXPORT_SYMBOL(pci_scan_root_bus);
>
> struct pci_bus *pci_scan_bus(int bus, struct pci_ops *ops,
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index 8a0321a..4d4f9d2 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -787,6 +787,10 @@ struct pci_bus *pci_create_root_bus(struct device *parent, int bus,
> int pci_bus_insert_busn_res(struct pci_bus *b, int bus, int busmax);
> int pci_bus_update_busn_res_end(struct pci_bus *b, int busmax);
> void pci_bus_release_busn_res(struct pci_bus *b);
> +struct pci_bus *pci_scan_root_bus_msi(struct device *parent, int bus,
> + struct pci_ops *ops, void *sysdata,
> + struct list_head *resources,
> + struct msi_controller *msi);
> struct pci_bus *pci_scan_root_bus(struct device *parent, int bus,
> struct pci_ops *ops, void *sysdata,
> struct list_head *resources);
> --
> 2.2.1
>
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