[PATCH v6 09/16] drivers: acpi: iort: add support for ARM SMMU platform devices creation
Lorenzo Pieralisi
lorenzo.pieralisi at arm.com
Mon Nov 7 03:39:43 PST 2016
On Tue, Nov 01, 2016 at 04:30:22PM -0600, Graeme Gregory wrote:
> On Fri, Oct 28, 2016 at 04:50:07PM +0100, Lorenzo Pieralisi wrote:
> > On Tue, Oct 18, 2016 at 05:04:07PM +0100, Lorenzo Pieralisi wrote:
> > > In ARM ACPI systems, IOMMU components are specified through static
> > > IORT table entries. In order to create platform devices for the
> > > corresponding ARM SMMU components, IORT kernel code should be made
> > > able to parse IORT table entries and create platform devices
> > > dynamically.
> > >
> > > This patch adds the generic IORT infrastructure required to create
> > > platform devices for ARM SMMUs.
> > >
> > > ARM SMMU versions have different resources requirement therefore this
> > > patch also introduces an IORT specific structure (ie iort_iommu_config)
> > > that contains hooks (to be defined when the corresponding ARM SMMU
> > > driver support is added to the kernel) to be used to define the
> > > platform devices names, init the IOMMUs, count their resources and
> > > finally initialize them.
> > >
> > > Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi at arm.com>
> > > Cc: Hanjun Guo <hanjun.guo at linaro.org>
> > > Cc: Tomasz Nowicki <tn at semihalf.com>
> > > Cc: "Rafael J. Wysocki" <rjw at rjwysocki.net>
> > > ---
> > > drivers/acpi/arm64/iort.c | 151 ++++++++++++++++++++++++++++++++++++++++++++++
> > > 1 file changed, 151 insertions(+)
> > >
> > > diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
> > > index 1433de3..2eda2f5 100644
> > > --- a/drivers/acpi/arm64/iort.c
> > > +++ b/drivers/acpi/arm64/iort.c
> > > @@ -19,9 +19,11 @@
> > > #define pr_fmt(fmt) "ACPI: IORT: " fmt
> > >
> > > #include <linux/acpi_iort.h>
> > > +#include <linux/iommu.h>
> > > #include <linux/kernel.h>
> > > #include <linux/list.h>
> > > #include <linux/pci.h>
> > > +#include <linux/platform_device.h>
> > > #include <linux/slab.h>
> > >
> > > struct iort_its_msi_chip {
> > > @@ -457,6 +459,153 @@ struct irq_domain *iort_get_device_domain(struct device *dev, u32 req_id)
> > > return irq_find_matching_fwnode(handle, DOMAIN_BUS_PCI_MSI);
> > > }
> > >
> > > +struct iort_iommu_config {
> > > + const char *name;
> > > + int (*iommu_init)(struct acpi_iort_node *node);
> > > + bool (*iommu_is_coherent)(struct acpi_iort_node *node);
> > > + int (*iommu_count_resources)(struct acpi_iort_node *node);
> > > + void (*iommu_init_resources)(struct resource *res,
> > > + struct acpi_iort_node *node);
> > > +};
> > > +
> > > +static __init
> > > +const struct iort_iommu_config *iort_get_iommu_cfg(struct acpi_iort_node *node)
> > > +{
> > > + return NULL;
> > > +}
> > > +
> > > +/**
> > > + * iort_add_smmu_platform_device() - Allocate a platform device for SMMU
> > > + * @node: Pointer to SMMU ACPI IORT node
> > > + *
> > > + * Returns: 0 on success, <0 failure
> > > + */
> > > +static int __init iort_add_smmu_platform_device(struct acpi_iort_node *node)
> > > +{
> > > + struct fwnode_handle *fwnode;
> > > + struct platform_device *pdev;
> > > + struct resource *r;
> > > + enum dev_dma_attr attr;
> > > + int ret, count;
> > > + const struct iort_iommu_config *ops = iort_get_iommu_cfg(node);
> > > +
> > > + if (!ops)
> > > + return -ENODEV;
> > > +
> > > + pdev = platform_device_alloc(ops->name, PLATFORM_DEVID_AUTO);
> > > + if (!pdev)
> > > + return PTR_ERR(pdev);
> > > +
> > > + count = ops->iommu_count_resources(node);
> > > +
> > > + r = kcalloc(count, sizeof(*r), GFP_KERNEL);
> > > + if (!r) {
> > > + ret = -ENOMEM;
> > > + goto dev_put;
> > > + }
> > > +
> > > + ops->iommu_init_resources(r, node);
> > > +
> > > + ret = platform_device_add_resources(pdev, r, count);
> > > + /*
> > > + * Resources are duplicated in platform_device_add_resources,
> > > + * free their allocated memory
> > > + */
> > > + kfree(r);
> > > +
> > > + if (ret)
> > > + goto dev_put;
> > > +
> > > + /*
> > > + * Add a copy of IORT node pointer to platform_data to
> > > + * be used to retrieve IORT data information.
> > > + */
> > > + ret = platform_device_add_data(pdev, &node, sizeof(node));
> > > + if (ret)
> > > + goto dev_put;
> > > +
> > > + /*
> > > + * We expect the dma masks to be equivalent for
> > > + * all SMMUs set-ups
> > > + */
> > > + pdev->dev.dma_mask = &pdev->dev.coherent_dma_mask;
> > > +
> > > + fwnode = iort_get_fwnode(node);
> > > +
> > > + if (!fwnode) {
> > > + ret = -ENODEV;
> > > + goto dev_put;
> > > + }
> > > +
> > > + pdev->dev.fwnode = fwnode;
> > > +
> > > + attr = ops->iommu_is_coherent(node) ?
> > > + DEV_DMA_COHERENT : DEV_DMA_NON_COHERENT;
> > > +
> > > + /* Configure DMA for the page table walker */
> > > + acpi_dma_configure(&pdev->dev, attr);
> > > +
> > > + ret = platform_device_add(pdev);
> > > + if (ret)
> > > + goto dma_deconfigure;
> > > +
> > > + return 0;
> > > +
> > > +dma_deconfigure:
> > > + acpi_dma_deconfigure(&pdev->dev);
> > > +dev_put:
> > > + platform_device_put(pdev);
> > > +
> > > + return ret;
> > > +}
> > > +
> > > +static void __init iort_init_platform_devices(void)
> > > +{
> > > + struct acpi_iort_node *iort_node, *iort_end;
> > > + struct acpi_table_iort *iort;
> > > + struct fwnode_handle *fwnode;
> > > + int i, ret;
> > > +
> > > + /*
> > > + * iort_table and iort both point to the start of IORT table, but
> > > + * have different struct types
> > > + */
> > > + iort = (struct acpi_table_iort *)iort_table;
> > > +
> > > + /* Get the first IORT node */
> > > + iort_node = ACPI_ADD_PTR(struct acpi_iort_node, iort,
> > > + iort->node_offset);
> > > + iort_end = ACPI_ADD_PTR(struct acpi_iort_node, iort,
> > > + iort_table->length);
> > > +
> > > + for (i = 0; i < iort->node_count; i++) {
> > > + if (iort_node >= iort_end) {
> > > + pr_err("iort node pointer overflows, bad table\n");
> > > + return;
> > > + }
> > > +
> > > + if ((iort_node->type == ACPI_IORT_NODE_SMMU) ||
> > > + (iort_node->type == ACPI_IORT_NODE_SMMU_V3)) {
> > > +
> > > + fwnode = acpi_alloc_fwnode_static();
> > > + if (!fwnode)
> > > + return;
> > > +
> > > + iort_set_fwnode(iort_node, fwnode);
> > > +
> > > + ret = iort_add_smmu_platform_device(iort_node);
> > > + if (ret) {
> > > + iort_delete_fwnode(iort_node);
> > > + acpi_free_fwnode_static(fwnode);
> > > + return;
> > > + }
> > > + }
> > > +
> > > + iort_node = ACPI_ADD_PTR(struct acpi_iort_node, iort_node,
> > > + iort_node->length);
> > > + }
> > > +}
> > > +
> > > void __init acpi_iort_init(void)
> > > {
> > > acpi_status status;
> > > @@ -468,5 +617,7 @@ void __init acpi_iort_init(void)
> > > return;
> > > }
> > >
> >
> > Slipped through the cracks while rebasing v6, I should add code that
> > returns if no IORT table found here to prevent calling:
> >
> > iort_init_platform_devices()
> >
> > I will update the next version, it is just a heads-up for testers,
> > I can push an updated/fixed branch if needed.
> >
>
> I could do with the updated branch.
Done, please find it here, I will post a v7 this week with updates.
git://git.kernel.org/pub/scm/linux/kernel/git/lpieralisi/linux.git acpi/iort-smmu-v6
Lorenzo
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