RE: [EXT] Re: [PATCH v2 12/12] bus: fsl-mc: Add ACPI support for fsl-mc

[Makarand Pawagi <makarand.pawagi@nxp.com>]

> -----Original Message-----
> From: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
> Sent: Wednesday, July 15, 2020 3:37 PM
> To: Makarand Pawagi <makarand.pawagi@nxp.com>
> Cc: Diana Madalina Craciun (OSS) <diana.craciun@oss.nxp.com>; Laurentiu
> Tudor <laurentiu.tudor@nxp.com>; linux-arm-kernel@lists.infradead.org;
> iommu@lists.linux-foundation.org; linux-acpi@vger.kernel.org;
> devicetree@vger.kernel.org; linux-pci@vger.kernel.org; Rob Herring
> <robh+dt@kernel.org>; Rafael J. Wysocki <rjw@rjwysocki.net>; Joerg Roedel
> <joro@8bytes.org>; Hanjun Guo <guohanjun@huawei.com>; Bjorn Helgaas
> <bhelgaas@google.com>; Sudeep Holla <sudeep.holla@arm.com>; Robin
> Murphy <robin.murphy@arm.com>; Catalin Marinas
> <catalin.marinas@arm.com>; Will Deacon <will@kernel.org>; Marc Zyngier
> <maz@kernel.org>
> Subject: Re: [EXT] Re: [PATCH v2 12/12] bus: fsl-mc: Add ACPI support for fsl-mc
> 
> Caution: EXT Email
> 
> On Thu, Jul 09, 2020 at 10:52:52AM +0000, Makarand Pawagi wrote:
> 
> [...]
> 
> > > >>>> fsl_mc_bus_probe(struct platform_device *pdev)
> > > >>>>>>      struct fsl_mc_io *mc_io = NULL;
> > > >>>>>>      int container_id;
> > > >>>>>>      phys_addr_t mc_portal_phys_addr;
> > > >>>>>> -   u32 mc_portal_size;
> > > >>>>>> -   struct resource res;
> > > >>>>>> +   u32 mc_portal_size, mc_stream_id;
> > > >>>>>> +   struct resource *plat_res;
> > > >>>>>> +
> > > >>>>>> +   if (!iommu_present(&fsl_mc_bus_type))
> > > >>>>>> +           return -EPROBE_DEFER;
> > > >>>>>>
> > > >>>>>>      mc = devm_kzalloc(&pdev->dev, sizeof(*mc), GFP_KERNEL);
> > > >>>>>>      if (!mc)
> > > >>>>>> @@ -874,19 +887,33 @@ static int fsl_mc_bus_probe(struct
> > > >>>>>> platform_device *pdev)
> > > >>>>>>
> > > >>>>>>      platform_set_drvdata(pdev, mc);
> > > >>>>>>
> > > >>>>>> +   plat_res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> > > >>>>>> +   mc->fsl_mc_regs = devm_ioremap_resource(&pdev->dev,
> plat_res);
> > > >>>>>> +   if (IS_ERR(mc->fsl_mc_regs))
> > > >>>>>> +           return PTR_ERR(mc->fsl_mc_regs);
> > > >>>>>> +
> > > >>>>>> +   if (IS_ENABLED(CONFIG_ACPI) && !dev_of_node(&pdev->dev)) {
> > > >>>>>> +           mc_stream_id = readl(mc->fsl_mc_regs + FSL_MC_FAPR);
> > > >>>>>> +           /*
> > > >>>>>> +            * HW ORs the PL and BMT bit, places the result in bit 15 of
> > > >>>>>> +            * the StreamID and ORs in the ICID. Calculate it accordingly.
> > > >>>>>> +            */
> > > >>>>>> +           mc_stream_id = (mc_stream_id & 0xffff) |
> > > >>>>>> +                           ((mc_stream_id & (MC_FAPR_PL | MC_FAPR_BMT)) ?
> > > >>>>>> +                                   0x4000 : 0);
> > > >>>>>> +           error = acpi_dma_configure_id(&pdev->dev,
> > > DEV_DMA_COHERENT,
> > > >>>>>> +                                         &mc_stream_id);
> > > >>>>>> +           if (error)
> > > >>>>>> +                   dev_warn(&pdev->dev, "failed to configure dma: %d.\n",
> > > >>>>>> +                            error);
> > > >>>>>> +   }
> > > >>>>>> +
> > > >>>>>>      /*
> > > >>>>>>       * Get physical address of MC portal for the root DPRC:
> > > >>>>>>       */
> > > >>>>>> -   error = of_address_to_resource(pdev->dev.of_node, 0, &res);
> > > >>>>>> -   if (error < 0) {
> > > >>>>>> -           dev_err(&pdev->dev,
> > > >>>>>> -                   "of_address_to_resource() failed for %pOF\n",
> > > >>>>>> -                   pdev->dev.of_node);
> > > >>>>>> -           return error;
> > > >>>>>> -   }
> > > >>>>>> -
> > > >>>>>> -   mc_portal_phys_addr = res.start;
> > > >>>>>> -   mc_portal_size = resource_size(&res);
> > > >>>>>> +   plat_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > > >>>>>> +   mc_portal_phys_addr = plat_res->start;
> > > >>>>>> +   mc_portal_size = resource_size(plat_res);
> > > >>>>>>      error = fsl_create_mc_io(&pdev->dev, mc_portal_phys_addr,
> > > >>>>>>                               mc_portal_size, NULL,
> > > >>>>>>
> > > >>>>>> FSL_MC_IO_ATOMIC_CONTEXT_PORTAL, &mc_io); @@ -903,11
> +930,13
> > > >>>>>> @@ static int fsl_mc_bus_probe(struct
> > > >>>> platform_device *pdev)
> > > >>>>>>      dev_info(&pdev->dev, "MC firmware version: %u.%u.%u\n",
> > > >>>>>>               mc_version.major, mc_version.minor,
> > > >>>>>> mc_version.revision);
> > > >>>>>>
> > > >>>>>> -   error = get_mc_addr_translation_ranges(&pdev->dev,
> > > >>>>>> -                                          &mc->translation_ranges,
> > > >>>>>> -                                          &mc->num_translation_ranges);
> > > >>>>>> -   if (error < 0)
> > > >>>>>> -           goto error_cleanup_mc_io;
> > > >>>>>> +   if (dev_of_node(&pdev->dev)) {
> > > >>>>>> +           error = get_mc_addr_translation_ranges(&pdev->dev,
> > > >>>>>> +                                           &mc->translation_ranges,
> > > >>>>>> +                                           &mc->num_translation_ranges);
> > > >>>>>> +           if (error < 0)
> > > >>>>>> +                   goto error_cleanup_mc_io;
> > > >>>>>> +   }
> > > >>>>>>
> > > >>>>>>      error = dprc_get_container_id(mc_io, 0, &container_id);
> > > >>>>>>      if (error < 0) {
> > > >>>>>> @@ -934,6 +963,7 @@ static int fsl_mc_bus_probe(struct
> > > >>>>>> platform_device
> > > >>>> *pdev)
> > > >>>>>>              goto error_cleanup_mc_io;
> > > >>>>>>
> > > >>>>>>      mc->root_mc_bus_dev = mc_bus_dev;
> > > >>>>>> +   mc_bus_dev->dev.fwnode = pdev->dev.fwnode;
> > > >>>>> Makarand, this looks a bit weird. Is there really a reason for it?
> > > >>>> Can you clarify please so that we can reach a conclusion on this matter ?
> > > >>>>
> > > >>> Laurentiu, can you clarify what exactly is the doubt here? Are
> > > >>> you asking about
> > > >> fwnode assignment from pdev to mc_bus_dev?
> > > >> Yes. I remember that a while ago I tested without this fwnode
> > > >> assignment and didn't encounter any issues. Maybe we can just drop it?
> > > > Did you tested with PHY changes? Because this is needed for MAC
> > > > driver,
> > > where it needs the mc bus node.
> > >
> > > Maybe it worth a comment or maybe have it in a different patch?
> > >
> > Since this change is needed for ACPI case and this is ACPI support
> > case, I feel we should have this change in this patch only instead of
> > separate patch.
> 
> Anyway - you need to seek feedback from Marc on whether patches
> 11 and 12 are OK from an irqchip perspective, it is possible we can take the rest
> of the series independently if everyone agrees but I don't necessarily see a
> reason for that.
> 
> Long story short: you need Marc's ACK on [11-12], it is your code.
> 
Hi Marc, can you please review/ack this patch?

> Thanks,
> Lorenzo