On Tue, Mar 03, 2020 at 05:55:05PM +0200, Laurentiu Tudor wrote:
> From c98dc05cdd45ae923654f2427985bd28bcde4bb2 Mon Sep 17 00:00:00 2001
> From: Laurentiu Tudor <laurentiu.tu...@nxp.com>
> Date: Thu, 13 Feb 2020 11:59:12 +0200
> Subject: [PATCH 1/4] bus: fsl-mc: add custom .dma_configure implementation
> Content-Type: text/plain; charset="us-ascii"
>
> The devices on this bus are not discovered by way of device tree
> but by queries to the firmware. It makes little sense to trick the
> generic of layer into thinking that these devices are of related so
> that we can get our dma configuration. Instead of doing that, add
> our custom dma configuration implementation.
Firstly, applying this to v5.5 results in a build failure, due to a
missing linux/iommu.h include.
Secondly, this on its own appears to make the DPAA2 network interfaces
completely disappear. Looking in /sys/bus/fsl-mc/drivers/*, none of
the DPAA2 drivers are bound to anything, and looking in
/sys/bus/fsl-mc/devices/, there is:
lrwxrwxrwx 1 root root 0 Mar 3 22:06 dprc.1 ->
../../../devices/platform/soc/80c000000.fsl-mc/dprc.1
This is booting with u-boot, so using DT rather than ACPI.
> Signed-off-by: Laurentiu Tudor <laurentiu.tu...@nxp.com>
> ---
> drivers/bus/fsl-mc/fsl-mc-bus.c | 42 ++++++++++++++++++++++++++++++++-
> 1 file changed, 41 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/bus/fsl-mc/fsl-mc-bus.c b/drivers/bus/fsl-mc/fsl-mc-bus.c
> index 36eb25f82c8e..3df015eedae4 100644
> --- a/drivers/bus/fsl-mc/fsl-mc-bus.c
> +++ b/drivers/bus/fsl-mc/fsl-mc-bus.c
> @@ -132,11 +132,51 @@ static int fsl_mc_bus_uevent(struct device *dev, struct
> kobj_uevent_env *env)
> static int fsl_mc_dma_configure(struct device *dev)
> {
> struct device *dma_dev = dev;
> + struct iommu_fwspec *fwspec;
> + const struct iommu_ops *iommu_ops;
> + struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
> + int ret;
> + u32 icid;
> +
> + /* Skip DMA setup for devices that are not DMA masters */
> + if (dev->type == &fsl_mc_bus_dpmcp_type ||
> + dev->type == &fsl_mc_bus_dpbp_type ||
> + dev->type == &fsl_mc_bus_dpcon_type ||
> + dev->type == &fsl_mc_bus_dpio_type)
> + return 0;
>
> while (dev_is_fsl_mc(dma_dev))
> dma_dev = dma_dev->parent;
>
> - return of_dma_configure(dev, dma_dev->of_node, 0);
> + fwspec = dev_iommu_fwspec_get(dma_dev);
> + if (!fwspec)
> + return -ENODEV;
The problem appears to be here - fwspec is NULL for dprc.1.
> + iommu_ops = iommu_ops_from_fwnode(fwspec->iommu_fwnode);
> + if (!iommu_ops)
> + return -ENODEV;
> +
> + ret = iommu_fwspec_init(dev, fwspec->iommu_fwnode, iommu_ops);
> + if (ret)
> + return ret;
> +
> + icid = mc_dev->icid;
> + ret = iommu_fwspec_add_ids(dev, &icid, 1);
> + if (ret) {
> + iommu_fwspec_free(dev);
> + return ret;
> + }
> +
> + if (!device_iommu_mapped(dev)) {
> + ret = iommu_probe_device(dev);
> + if (ret) {
> + iommu_fwspec_free(dev);
> + return ret;
> + }
> + }
> +
> + arch_setup_dma_ops(dev, 0, *dma_dev->dma_mask + 1, iommu_ops, true);
> +
> + return 0;
> }
>
> static ssize_t modalias_show(struct device *dev, struct device_attribute
> *attr,
> --
> 2.17.1
>
--
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up
According to speedtest.net: 11.9Mbps down 500kbps up
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
