Re: [RFC PATCH 4/4] ACPI: IORT: Add SMMUv3 MSI support

Hanjun Guo
2017-08-17T07:49:56Z

Hi Lorenzo,

On 2017/8/16 1:15, Lorenzo Pieralisi wrote:
> On Fri, Aug 11, 2017 at 09:56:31PM +0800, Hanjun Guo wrote:
>> Hi Lorenzo,
>>
>> On 11 August 2017 at 17:33, Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> wrote:
>>> On Wed, Aug 09, 2017 at 06:53:37PM +0800, Hanjun Guo wrote:
>>>> From: Hanjun Guo <hanjun.guo@linaro.org>
>>>>
>>>> Since we have a mapping index for SMMUv3 MSI, we can
>>>> directly use that index to get the map entry, then
>>>> retrieve dev ID and ITS parent to add SMMUv3 MSI
>>>> support.
>>>>
>>>> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
>>>> ---
>>>> drivers/acpi/arm64/iort.c | 46 ++++++++++++++++++++++++++++++++++++----------
>>>> 1 file changed, 36 insertions(+), 10 deletions(-)
>>>>
>>>> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
>>>> index 9439f02..ce03298 100644
>>>> --- a/drivers/acpi/arm64/iort.c
>>>> +++ b/drivers/acpi/arm64/iort.c
>>>> @@ -313,7 +313,8 @@ static int iort_id_map(struct acpi_iort_id_mapping *map, u8 type, u32 rid_in,
>>>> /* Single mapping does not care for input id */
>>>> if (map->flags & ACPI_IORT_ID_SINGLE_MAPPING) {
>>>> if (type == ACPI_IORT_NODE_NAMED_COMPONENT ||
>>>> - type == ACPI_IORT_NODE_PCI_ROOT_COMPLEX) {
>>>> + type == ACPI_IORT_NODE_PCI_ROOT_COMPLEX ||
>>>> + type == ACPI_IORT_NODE_SMMU_V3) {
>>>> *rid_out = map->output_base;
>>>> return 0;
>>>> }
>>>> @@ -357,7 +358,8 @@ struct acpi_iort_node *iort_node_get_id(struct acpi_iort_node *node,
>>>>
>>>> if (map->flags & ACPI_IORT_ID_SINGLE_MAPPING) {
>>>> if (node->type == ACPI_IORT_NODE_NAMED_COMPONENT ||
>>>> - node->type == ACPI_IORT_NODE_PCI_ROOT_COMPLEX) {
>>>> + node->type == ACPI_IORT_NODE_PCI_ROOT_COMPLEX ||
>>>> + node->type == ACPI_IORT_NODE_SMMU_V3) {
>>>> *id_out = map->output_base;
>>>> return parent;
>>>> }
>>>> @@ -549,9 +551,21 @@ int iort_pmsi_get_dev_id(struct device *dev, u32 *dev_id)
>>>> if (!node)
>>>> return -ENODEV;
>>>>
>>>> - for (i = 0; i < node->mapping_count; i++) {
>>>> - if (iort_node_map_platform_id(node, dev_id, IORT_MSI_TYPE, i))
>>>> + if (node->type == ACPI_IORT_NODE_SMMU_V3) {
>>>> + u32 index;
>>>> +
>>>> + if (iort_get_smmu_v3_id_mapping_index(node, &index))
>>>> + return -ENODEV;
>>>> +
>>>> + if (iort_node_map_platform_id(node, dev_id, IORT_MSI_TYPE,
>>>> + index))
>>>> return 0;
>>>> + } else {
>>>> + for (i = 0; i < node->mapping_count; i++) {
>>>> + if (iort_node_map_platform_id(node, dev_id,
>>>> + IORT_MSI_TYPE, i))
>>>> + return 0;
>>>> + }
>>>> }
>>>>
>>>> return -ENODEV;
>>>> @@ -626,20 +640,30 @@ static struct irq_domain *iort_get_platform_device_domain(struct device *dev)
>>>> struct acpi_iort_node *node, *msi_parent;
>>>> struct fwnode_handle *iort_fwnode;
>>>> struct acpi_iort_its_group *its;
>>>> - int i;
>>>>
>>>> /* find its associated iort node */
>>>> - node = iort_scan_node(ACPI_IORT_NODE_NAMED_COMPONENT,
>>>> - iort_match_node_callback, dev);
>>>> + node = iort_find_dev_node(dev);
>>>> if (!node)
>>>> return NULL;
>>>>
>>>> /* then find its msi parent node */
>>>> - for (i = 0; i < node->mapping_count; i++) {
>>>> + if (node->type == ACPI_IORT_NODE_SMMU_V3) {
>>>> + u32 index;
>>>> +
>>>> + if (iort_get_smmu_v3_id_mapping_index(node, &index))
>>>> + return NULL;
>>>> +
>>>> msi_parent = iort_node_map_platform_id(node, NULL,
>>>> + IORT_MSI_TYPE, index);
>>>> + } else {
>>>> + int i;
>>>> +
>>>> + for (i = 0; i < node->mapping_count; i++) {
>>>> + msi_parent = iort_node_map_platform_id(node, NULL,
>>>> IORT_MSI_TYPE, i);
>>>> - if (msi_parent)
>>>> - break;
>>>> + if (msi_parent)
>>>> + break;
>>>> + }
>>>> }
>>>>
>>>> if (!msi_parent)
>>>> @@ -1233,6 +1257,8 @@ static int __init iort_add_smmu_platform_device(struct acpi_iort_node *node)
>>>> /* Configure DMA for the page table walker */
>>>> acpi_dma_configure(&pdev->dev, attr);
>>>>
>>>> + acpi_configure_pmsi_domain(&pdev->dev);
>>>
>>> I think this is just overkill. There are two separate things to solve
>>> here:
>>>
>>> 1) Make single mappings valid for SMMUv3 (and PMCG); that's fair enough
>>> and goes with the logic to skip the ITS DeviceID index for "normal"
>>> mappings, I can live with that
>>> 2) Find the MSI domain for an SMMUv3 (or any other IORT table node); I
>>> do not think you need all this complexity to do it via
>>> acpi_configure_pmsi_domain(), it can be done in a easier way with
>>> an ad-hoc stub (it does not even have to be SMMUv3 specific)
>>>
>>> My worry is that we are peppering the generic IORT mapping code with
>>> node types specific kludges and it is becoming a mess.
>>
>> Agreed.
>>
>>>
>>> I can rework the patch to show you what I have in mind, please let
>>> me know.
>>
>> Please, thank you very much for doing so.
>
> Here, untested just to get your opinion, please let me know.
>
> Thanks,
> Lorenzo
>
> -- >8 --
> Subject: [PATCH 4/4] ACPI/IORT: IORT nodes MSI handling
>
> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
> ---
> drivers/acpi/arm64/iort.c | 76 +++++++++++++++++++++++++++++++++++++++--------
> 1 file changed, 63 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c
> index 24678c3..21a0aab 100644
> --- a/drivers/acpi/arm64/iort.c
> +++ b/drivers/acpi/arm64/iort.c
> @@ -366,7 +366,7 @@ struct acpi_iort_node *iort_node_get_id(struct acpi_iort_node *node,
> return NULL;
> }
>
> -static int iort_get_smmu_v3_id_mapping_index(struct acpi_iort_node *node,
> +static int iort_get_id_mapping_index(struct acpi_iort_node *node,
> u32 *index)
> {
> struct acpi_iort_smmu_v3 *smmu;
> @@ -378,20 +378,25 @@ static int iort_get_smmu_v3_id_mapping_index(struct acpi_iort_node *node,
> if (node->revision < 1)
> return -EINVAL;
>
> - smmu = (struct acpi_iort_smmu_v3 *)node->node_data;
> - /* if any of the gsi for control interrupts is not 0, ignore the MSI */
> - if (smmu->event_gsiv || smmu->pri_gsiv || smmu->gerr_gsiv
> - || smmu->sync_gsiv)
> - return -EINVAL;
> + switch (node->type) {
> + case ACPI_IORT_NODE_SMMU_V3:
> + smmu = (struct acpi_iort_smmu_v3 *)node->node_data;
> + /* if any of the gsi for control interrupts is not 0, ignore the MSI */
> + if (smmu->event_gsiv || smmu->pri_gsiv || smmu->gerr_gsiv
> + || smmu->sync_gsiv)
> + return -EINVAL;
> +
> + if (smmu->id_mapping_index >= node->mapping_count) {
> + pr_err(FW_BUG "[node %p type %d] ID mapping index overflows valid mappings\n",
> + node, node->type);
> + return -EINVAL;
> + }
>
> - if (smmu->id_mapping_index >= node->mapping_count) {
> - pr_err(FW_BUG "[node %p type %d] ID mapping index overflows valid mappings\n",
> - node, node->type);
> + *index = smmu->id_mapping_index;
> + return 0;
> + default:
> return -EINVAL;
> }
> -
> - *index = smmu->id_mapping_index;
> - return 0;
> }
>
> static struct acpi_iort_node *iort_node_map_id(struct acpi_iort_node *node,
> @@ -431,7 +436,7 @@ static struct acpi_iort_node *iort_node_map_id(struct acpi_iort_node *node,
> * associated ID map for single mapping cases.
> */
> if (node->type == ACPI_IORT_NODE_SMMU_V3)
> - ret = iort_get_smmu_v3_id_mapping_index(node, &index);
> + ret = iort_get_id_mapping_index(node, &index);
>
> /* Do the ID translation */
> for (i = 0; i < node->mapping_count; i++, map++) {
> @@ -620,6 +625,49 @@ struct irq_domain *iort_get_device_domain(struct device *dev, u32 req_id)
> return irq_find_matching_fwnode(handle, DOMAIN_BUS_PCI_MSI);
> }
>
> +static void iort_set_device_domain(struct device *dev,
> + struct acpi_iort_node *node)
> +{
> + struct acpi_iort_its_group *its;
> + struct acpi_iort_node *msi_parent;
> + struct acpi_iort_id_mapping *map;
> + struct fwnode_handle *iort_fwnode;
> + struct irq_domain *domain;
> + int ret, index;
> +
> + ret = iort_get_id_mapping_index(node, &index);
> + if (ret < 0)
> + return;
> +
> + map = ACPI_ADD_PTR(struct acpi_iort_id_mapping, node,
> + node->mapping_offset + index * sizeof(*map));
> +
> + /* Firmware bug! */
> + if (!map->output_reference ||
> + !(map->flags & ACPI_IORT_ID_SINGLE_MAPPING)) {
> + pr_err(FW_BUG "[node %p type %d] Invalid MSI mapping\n",
> + node, node->type);
> + return;
> + }
> +
> + msi_parent = ACPI_ADD_PTR(struct acpi_iort_node, iort_table,
> + map->output_reference);
> +
> + if (!msi_parent || msi_parent->type != ACPI_IORT_NODE_ITS_GROUP)
> + return;
> +
> + /* Move to ITS specific data */
> + its = (struct acpi_iort_its_group *)msi_parent->node_data;
> +
> + iort_fwnode = iort_find_domain_token(its->identifiers[0]);
> + if (!iort_fwnode)
> + return;
> +
> + domain = irq_find_matching_fwnode(iort_fwnode, DOMAIN_BUS_PLATFORM_MSI);
> + if (domain)
> + dev_set_msi_domain(dev, domain);
> +}
> +
> /**
> * iort_get_platform_device_domain() - Find MSI domain related to a
> * platform device
> @@ -1159,6 +1207,8 @@ static int __init iort_add_smmu_platform_device(struct acpi_iort_node *node)
> /* Configure DMA for the page table walker */
> acpi_dma_configure(&pdev->dev, attr);
>
> + iort_set_device_domain(&pdev->dev, node);

This is fine to me, but I think we still need to retrieve
the output ID as the request id for ITS, which means we
need to do that in iort_pmsi_get_dev_id(), right?

Thanks
Hanjun