ARM/PCI, designware, xilinx: Use pci_scan_root_bus_msi()

ARM previously stored the msi_controller pointer in its sysdata, struct
pci_sys_data, and implemented pcibios_msi_controller() to retrieve it.
That made PCI host controller drivers specific to ARM because they had to
put the msi_controller pointer in the ARM-specific pci_sys_data.

There is now a generic mechanism, pci_scan_root_bus_msi(), for giving the
msi_controller pointer to the PCI core.  Use this for all ARM systems and
for the DesignWare and Xilinx PCI host controller drivers.

This removes an ARM dependency from the DesignWare, DRA7xx, EXYNOS, i.MX6,
Keystone, Layerscape, SPEAr13xx, and Xilinx drivers.

[bhelgaas: changelog, split into separate patch]
Suggested-by: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Jingoo Han <jingoohan1@gmail.com>
CC: Pratyush Anand <pratyush.anand@gmail.com>
CC: Arnd Bergmann <arnd@arndb.de>
CC: Simon Horman <horms@verge.net.au>
CC: Russell King <linux@arm.linux.org.uk>
CC: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
CC: Thierry Reding <thierry.reding@gmail.com>
CC: Michal Simek <michal.simek@xilinx.com>
CC: Marc Zyngier <marc.zyngier@arm.com>

4 files changed, 20 insertions, 10 deletions

diff --git a/arch/arm/include/asm/mach/pci.h b/arch/arm/include/asm/mach/pci.h
index 28b9bb35949e..c074e7a319e7 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;
diff --git a/arch/arm/kernel/bios32.c b/arch/arm/kernel/bios32.c
index 4e95260efb39..283bc1c7b502 100644
--- a/arch/arm/kernel/bios32.c
+++ b/arch/arm/kernel/bios32.c
@@ -486,8 +486,9 @@ 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 69486be7181e..fe11cc175f77 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;
@@ -708,8 +707,15 @@ 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,
-                                  &dw_pcie_ops, sys, &sys->resources);
+
+        if (IS_ENABLED(CONFIG_PCI_MSI))
+                bus = pci_scan_root_bus_msi(pp->dev, sys->busnr, &dw_pcie_ops,
+                                            sys, &sys->resources,
+                                            &dw_pcie_msi_chip);
+        else
+                bus = pci_scan_root_bus(pp->dev, sys->busnr, &dw_pcie_ops,
+                                        sys, &sys->resources);
+
         if (!bus)
                 return NULL;
 
diff --git a/drivers/pci/host/pcie-xilinx.c b/drivers/pci/host/pcie-xilinx.c
index f1a06a091ccb..38d3114b97d3 100644
--- a/drivers/pci/host/pcie-xilinx.c
+++ b/drivers/pci/host/pcie-xilinx.c
@@ -647,9 +647,15 @@ 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,
-                                sys, &sys->resources);
 
+        if (IS_ENABLED(CONFIG_PCI_MSI))
+                bus = pci_scan_root_bus_msi(port->dev, sys->busnr,
+                                            &xilinx_pcie_ops, sys,
+                                            &sys->resources,
+                                            &xilinx_pcie_msi_chip);
+        else
+                bus = pci_scan_root_bus(port->dev, sys->busnr,
+                                        &xilinx_pcie_ops, sys, &sys->resources);
         return bus;
 }
 
@@ -847,7 +853,6 @@ 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);