Commit 416379f9 authored Oct 14, 2016 by Niklas Cassel Committed by Bjorn Helgaas Nov 04, 2016

PCI: designware: Check for iATU unroll support after initializing host



dw_pcie_iatu_unroll_enabled() reads a dbi_base register.  Reading any
dbi_base register before pp->ops->host_init has been called causes
"imprecise external abort" on platforms like ARTPEC-6, where the PCIe
module is disabled at boot and first enabled in pp->ops->host_init.  Move
dw_pcie_iatu_unroll_enabled() to dw_pcie_setup_rc(), since it is after
pp->ops->host_init, but before pp->iatu_unroll_enabled is actually used.

Fixes: a0601a47 ("PCI: designware: Add iATU Unroll feature")
Tested-by: James Le Cuirot <chewi@gentoo.org>
Signed-off-by: Niklas Cassel <niklas.cassel@axis.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Joao Pinto <jpinto@synopsys.com>
Acked-by: Olof Johansson <olof@lixom.net>

parent ad110449

drivers/pci/host/pcie-designware.c

+5 −2

Original line number	Diff line number	Diff line
		@@ -637,8 +637,6 @@ int dw_pcie_host_init(struct pcie_port *pp)
		}
		}

		pp->iatu_unroll_enabled = dw_pcie_iatu_unroll_enabled(pp);

		if (pp->ops->host_init)
		pp->ops->host_init(pp);

		@@ -809,6 +807,11 @@ void dw_pcie_setup_rc(struct pcie_port *pp)
		{
		u32 val;

		/* get iATU unroll support */
		pp->iatu_unroll_enabled = dw_pcie_iatu_unroll_enabled(pp);
		dev_dbg(pp->dev, "iATU unroll: %s\n",
		pp->iatu_unroll_enabled ? "enabled" : "disabled");

		/* set the number of lanes */
		val = dw_pcie_readl_rc(pp, PCIE_PORT_LINK_CONTROL);
		val &= ~PORT_LINK_MODE_MASK;