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@xxxxxxx>
> Cc: Hanjun Guo <hanjun.guo@xxxxxxxxxx>
> Cc: Tomasz Nowicki <tn@xxxxxxxxxxxx>
> Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
> ---
> 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.
Thanks,
Lorenzo
> + iort_init_platform_devices();
> +
> acpi_probe_device_table(iort);
> }
> --
> 2.10.0
>
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