From 31e45ec3a4e73dcbeb51e03ab559812ba3e82cc2 Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Thu, 26 Dec 2013 16:52:41 +0100 Subject: [PATCH] PCI: mvebu: Call pci_ioremap_io() at startup instead of dynamically The mvebu PCI host controller driver uses an emulated PCI-to-PCI bridge to leverage the core PCI kernel enumeration logic to dynamically create and remove the MBus windows needed to access the memory and I/O regions of each PCI interface. In the context of this PCI-to-PCI bridge emulation, the driver emulates all reads and writes to the PCI bridge registers. Upon a write to the registers configuring the I/O base and limit, the driver was creating the MBus window and calling pci_ioremap_io() to setup the mapping. However, it turns out that accesses to these registers are made in an IRQ disabled context, while pci_ioremap_io() is a potentially sleeping function. Not only this is wrong, but it is causing fairly loud warnings at boot time when the appropriate kernel hacking options are enabled. This patch solves this by moving the pci_ioremap_io() call to the startup of the driver. At this point, we don't know how many PCI interfaces will be enabled, so we are simply remapping the entire PCI I/O space to virtual addresses. This is reasonable since this I/O space is limited to 1 MB in size, and also because the MBus windows continue to be created in a dynamic fashion only when devices need them. Signed-off-by: Thomas Petazzoni Signed-off-by: Bjorn Helgaas --- drivers/pci/host/pci-mvebu.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/pci/host/pci-mvebu.c b/drivers/pci/host/pci-mvebu.c index afd2af04980c..18057905689a 100644 --- a/drivers/pci/host/pci-mvebu.c +++ b/drivers/pci/host/pci-mvebu.c @@ -342,8 +342,6 @@ static void mvebu_pcie_handle_iobase_change(struct mvebu_pcie_port *port) mvebu_mbus_add_window_remap_by_id(port->io_target, port->io_attr, port->iowin_base, port->iowin_size, iobase); - - pci_ioremap_io(iobase, port->iowin_base); } static void mvebu_pcie_handle_membase_change(struct mvebu_pcie_port *port) @@ -988,6 +986,10 @@ static int mvebu_pcie_probe(struct platform_device *pdev) } pcie->nports = i; + + for (i = 0; i < (IO_SPACE_LIMIT - SZ_64K); i += SZ_64K) + pci_ioremap_io(i, pcie->io.start + i); + mvebu_pcie_msi_enable(pcie); mvebu_pcie_enable(pcie);