Hi Robin, >On 25/04/16 16:58, Sricharan R wrote: >> From: Laurent Pinchart <[email protected]> >> >> Configuring DMA ops at probe time will allow deferring device probe when >> the IOMMU isn't available yet. >> >> Signed-off-by: Laurent Pinchart <[email protected]> >> --- >> drivers/base/platform.c | 13 +++++++++++++ >> drivers/of/platform.c | 7 +++---- >> 2 files changed, 16 insertions(+), 4 deletions(-) >> >> diff --git a/drivers/base/platform.c b/drivers/base/platform.c >> index f437afa..17e64a4 100644 >> --- a/drivers/base/platform.c >> +++ b/drivers/base/platform.c >> @@ -557,6 +557,12 @@ static int platform_drv_probe(struct device *_dev) >> if (ret < 0) >> return ret; >> >> + if (of_have_populated_dt()) { >> + ret = of_dma_configure_ops(_dev, _dev->of_node); >> + if (ret < 0) >> + goto done; >> + } >> + >> ret = dev_pm_domain_attach(_dev, true); >> if (ret != -EPROBE_DEFER) { >> if (drv->probe) { >> @@ -569,6 +575,11 @@ static int platform_drv_probe(struct device *_dev) >> } >> } >> >> + if (of_have_populated_dt()) { >> + if (ret) >> + of_dma_deconfigure(_dev); >> + } >> +done: >> if (drv->prevent_deferred_probe && ret == -EPROBE_DEFER) { >> dev_warn(_dev, "probe deferral not supported\n"); >> ret = -ENXIO; >> @@ -591,6 +602,8 @@ static int platform_drv_remove(struct device *_dev) >> if (drv->remove) >> ret = drv->remove(dev); >> dev_pm_domain_detach(_dev, true); >> + if (of_have_populated_dt()) >> + of_dma_deconfigure(_dev); >> >> return ret; >> } >> diff --git a/drivers/of/platform.c b/drivers/of/platform.c >> index 17ee8d5..12bbc8e1 100644 >> --- a/drivers/of/platform.c >> +++ b/drivers/of/platform.c >> @@ -180,11 +180,9 @@ static struct platform_device >> *of_platform_device_create_pdata( >> dev->dev.bus = &platform_bus_type; >> dev->dev.platform_data = platform_data; >> of_dma_configure_masks(&dev->dev, dev->dev.of_node); >> - of_dma_configure_ops(&dev->dev, dev->dev.of_node); >> of_msi_configure(&dev->dev, dev->dev.of_node); >> >> if (of_device_add(dev) != 0) { >> - of_dma_deconfigure(&dev->dev); >> platform_device_put(dev); >> goto err_clear_flag; >> } >> @@ -481,11 +479,12 @@ static int of_platform_device_destroy(struct device >> *dev, void *data) >> if (dev->bus == &platform_bus_type) >> platform_device_unregister(to_platform_device(dev)); >> #ifdef CONFIG_ARM_AMBA >> - else if (dev->bus == &amba_bustype) >> + else if (dev->bus == &amba_bustype) { >> amba_device_unregister(to_amba_device(dev)); >> + of_dma_deconfigure(dev); >> + } > >Note that we definitely need this to happen properly on other buses, >too. I had something for the AMBA bus back when I last looked at >this[0], but since then we now have PCI devices going through the >of_dma_configure() path as well (hence 226d89cbb242). > >There's also now some initial ACPI code in flight[1], so it's probably >about time to take another closer look at how this can be properly >generalised, but I'm not necessarily averse to starting with a >DT-focused solution that gets at least half way, then building on top of >that.
Thanks for direction. I will definitely look at how this can be generalised for other buses as well. Based on how that looks, as you said if required a DT-only can be done first. Regards, Sricharan _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
