3e3e406e38
This fixes a boot hang observed when the bootloader already enabled the PCIe link for its own use. The fundamental problem is that Freescale forgot to wire up the core reset, so software doesn't have a sane way to get the core into a defined state. According to the DW PCIe core reference manual, configuration of the core may only happen when the LTSSM is disabled, so this is one of the first things we need to do. Apparently this isn't safe to do when the LTSSM is in any state other than "detect" as we observe an instant machine hang when trying to do so while the link is already up. As a workaround, force LTSSM into detect state right before hitting the disable switch. There is still a race window because the LTSSM may transition out of "detect" before we can disable it, but it's the best we can do for now. [bhelgaas: mention race window] Link: http://lkml.kernel.org/r/1406830565-23450-3-git-send-email-l.stach@pengutronix.de Reported-by: Fabio Estevam <fabio.estevam@freescale.com> Signed-off-by: Lucas Stach <l.stach@pengutronix.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Tim Harvey <tharvey@gateworks.com> |
||
|---|---|---|
| .. | ||
| Kconfig | ||
| Makefile | ||
| pci-dra7xx.c | ||
| pci-exynos.c | ||
| pci-host-generic.c | ||
| pci-imx6.c | ||
| pci-mvebu.c | ||
| pci-rcar-gen2.c | ||
| pci-tegra.c | ||
| pcie-designware.c | ||
| pcie-designware.h | ||
| pcie-rcar.c | ||
| pcie-spear13xx.c | ||