Devices on cdx bus are dynamically detected and registered using platform_device_register API. As these devices are not linked to of node they need a separate MSI domain for handling device ID to be provided to the GIC ITS domain. This also introduces APIs to alloc and free IRQs for CDX domain. Signed-off-by: Nipun Gupta <nipun.gupta@xxxxxxx> Signed-off-by: Nikhil Agarwal <nikhil.agarwal@xxxxxxx> --- drivers/bus/cdx/cdx.c | 18 +++ drivers/bus/cdx/cdx.h | 19 +++ drivers/bus/cdx/cdx_msi.c | 236 +++++++++++++++++++++++++++++++++++ drivers/bus/cdx/mcdi_stubs.c | 1 + include/linux/cdx/cdx_bus.h | 19 +++ 5 files changed, 293 insertions(+) create mode 100644 drivers/bus/cdx/cdx_msi.c diff --git a/drivers/bus/cdx/cdx.c b/drivers/bus/cdx/cdx.c index fc417c32c59b..02ececce1c84 100644 --- a/drivers/bus/cdx/cdx.c +++ b/drivers/bus/cdx/cdx.c @@ -17,6 +17,7 @@ #include <linux/dma-map-ops.h> #include <linux/property.h> #include <linux/iommu.h> +#include <linux/msi.h> #include <linux/cdx/cdx_bus.h> #include "cdx.h" @@ -236,6 +237,7 @@ static int cdx_device_add(struct device *parent, struct cdx_dev_params_t *dev_params) { struct cdx_device *cdx_dev; + struct irq_domain *cdx_msi_domain; int ret; cdx_dev = kzalloc(sizeof(*cdx_dev), GFP_KERNEL); @@ -252,6 +254,7 @@ static int cdx_device_add(struct device *parent, /* Populate CDX dev params */ cdx_dev->req_id = dev_params->req_id; + cdx_dev->num_msi = dev_params->num_msi; cdx_dev->vendor = dev_params->vendor; cdx_dev->device = dev_params->device; cdx_dev->bus_id = dev_params->bus_id; @@ -269,6 +272,21 @@ static int cdx_device_add(struct device *parent, dev_set_name(&cdx_dev->dev, "cdx-%02x:%02x", cdx_dev->bus_id, cdx_dev->func_id); + /* If CDX MSI domain is not created, create one. */ + cdx_msi_domain = cdx_find_msi_domain(parent); + if (!cdx_msi_domain) { + cdx_msi_domain = cdx_msi_domain_init(parent); + if (!cdx_msi_domain) { + dev_err(&cdx_dev->dev, + "cdx_msi_domain_init() failed: %d", ret); + kfree(cdx_dev); + return -1; + } + } + + /* Set the MSI domain */ + dev_set_msi_domain(&cdx_dev->dev, cdx_msi_domain); + ret = device_add(&cdx_dev->dev); if (ret != 0) { dev_err(&cdx_dev->dev, diff --git a/drivers/bus/cdx/cdx.h b/drivers/bus/cdx/cdx.h index db0569431c10..95df440ebd73 100644 --- a/drivers/bus/cdx/cdx.h +++ b/drivers/bus/cdx/cdx.h @@ -20,6 +20,7 @@ * @res: array of MMIO region entries * @res_count: number of valid MMIO regions * @req_id: Requestor ID associated with CDX device + * @num_msi: Number of MSI's supported by the device */ struct cdx_dev_params_t { u16 vendor; @@ -29,6 +30,24 @@ struct cdx_dev_params_t { struct resource res[MAX_CDX_DEV_RESOURCES]; u8 res_count; u32 req_id; + u32 num_msi; }; +/** + * cdx_msi_domain_init - Init the CDX bus MSI domain. + * @dev: Device of the CDX bus controller + * + * Return CDX MSI domain, NULL on failure + */ +struct irq_domain *cdx_msi_domain_init(struct device *dev); + +/** + * cdx_find_msi_domain - Get the CDX-MSI domain. + * @dev: CDX controller generic device + * + * Return CDX MSI domain, NULL on error or if CDX-MSI domain is + * not yet created. + */ +struct irq_domain *cdx_find_msi_domain(struct device *parent); + #endif /* _CDX_H_ */ diff --git a/drivers/bus/cdx/cdx_msi.c b/drivers/bus/cdx/cdx_msi.c new file mode 100644 index 000000000000..2fb7bac18393 --- /dev/null +++ b/drivers/bus/cdx/cdx_msi.c @@ -0,0 +1,236 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * AMD CDX bus driver MSI support + * + * Copyright (C) 2022, Advanced Micro Devices, Inc. + * + */ + +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/irq.h> +#include <linux/irqdomain.h> +#include <linux/msi.h> +#include <linux/cdx/cdx_bus.h> + +#include "cdx.h" + +#ifdef GENERIC_MSI_DOMAIN_OPS +/* + * Generate a unique ID identifying the interrupt (only used within the MSI + * irqdomain. Combine the req_id with the interrupt index. + */ +static irq_hw_number_t cdx_domain_calc_hwirq(struct cdx_device *dev, + struct msi_desc *desc) +{ + /* + * Make the base hwirq value for req_id*10000 so it is readable + * as a decimal value in /proc/interrupts. + */ + return (irq_hw_number_t)(desc->msi_index + (dev->req_id * 10000)); +} + +static void cdx_msi_set_desc(msi_alloc_info_t *arg, + struct msi_desc *desc) +{ + arg->desc = desc; + arg->hwirq = cdx_domain_calc_hwirq(to_cdx_device(desc->dev), desc); +} +#else +#define cdx_msi_set_desc NULL +#endif + +static void cdx_msi_update_dom_ops(struct msi_domain_info *info) +{ + struct msi_domain_ops *ops = info->ops; + + if (!ops) + return; + + /* set_desc should not be set by the caller */ + if (!ops->set_desc) + ops->set_desc = cdx_msi_set_desc; +} + +static void cdx_msi_write_msg(struct irq_data *irq_data, + struct msi_msg *msg) +{ + /* + * Do nothing as CDX devices have these pre-populated + * in the hardware itself. + */ +} + +static void cdx_msi_update_chip_ops(struct msi_domain_info *info) +{ + struct irq_chip *chip = info->chip; + + if (!chip) + return; + + /* + * irq_write_msi_msg should not be set by the caller + */ + if (!chip->irq_write_msi_msg) + chip->irq_write_msi_msg = cdx_msi_write_msg; +} +/** + * cdx_msi_create_irq_domain - Create a CDX MSI interrupt domain + * @fwnode: Optional firmware node of the interrupt controller + * @info: MSI domain info + * @parent: Parent irq domain + * + * Updates the domain and chip ops and creates a CDX MSI + * interrupt domain. + * + * Returns: + * A domain pointer or NULL in case of failure. + */ +static struct irq_domain *cdx_msi_create_irq_domain(struct fwnode_handle *fwnode, + struct msi_domain_info *info, + struct irq_domain *parent) +{ + if (WARN_ON((info->flags & MSI_FLAG_LEVEL_CAPABLE))) + info->flags &= ~MSI_FLAG_LEVEL_CAPABLE; + if (info->flags & MSI_FLAG_USE_DEF_DOM_OPS) + cdx_msi_update_dom_ops(info); + if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS) + cdx_msi_update_chip_ops(info); + info->flags |= MSI_FLAG_ALLOC_SIMPLE_MSI_DESCS | MSI_FLAG_FREE_MSI_DESCS; + + return msi_create_irq_domain(fwnode, info, parent); +} + +int cdx_msi_domain_alloc_irqs(struct device *dev, unsigned int irq_count) +{ + struct irq_domain *msi_domain; + int ret; + + msi_domain = dev_get_msi_domain(dev); + if (!msi_domain) { + dev_err(dev, "msi domain get failed\n"); + return -EINVAL; + } + + ret = msi_setup_device_data(dev); + if (ret) { + dev_err(dev, "msi setup device failed: %d\n", ret); + return ret; + } + + msi_lock_descs(dev); + if (msi_first_desc(dev, MSI_DESC_ALL)) + ret = -EINVAL; + msi_unlock_descs(dev); + if (ret) { + dev_err(dev, "msi setup device failed: %d\n", ret); + return ret; + } + + ret = msi_domain_alloc_irqs(msi_domain, dev, irq_count); + if (ret) + dev_err(dev, "Failed to allocate IRQs\n"); + + return ret; +} +EXPORT_SYMBOL(cdx_msi_domain_alloc_irqs); + +void cdx_msi_domain_free_irqs(struct device *dev) +{ + struct irq_domain *msi_domain; + + msi_domain = dev_get_msi_domain(dev); + if (!msi_domain) + return; + + msi_domain_free_irqs(msi_domain, dev); +} +EXPORT_SYMBOL(cdx_msi_domain_free_irqs); + +static struct irq_chip cdx_msi_irq_chip = { + .name = "CDX-MSI", + .irq_mask = irq_chip_mask_parent, + .irq_unmask = irq_chip_unmask_parent, + .irq_eoi = irq_chip_eoi_parent, + .irq_set_affinity = msi_domain_set_affinity +}; + +static int cdx_msi_prepare(struct irq_domain *msi_domain, + struct device *dev, + int nvec, msi_alloc_info_t *info) +{ + struct cdx_device *cdx_dev = to_cdx_device(dev); + struct msi_domain_info *msi_info; + struct device *parent = dev->parent; + u32 dev_id; + int ret; + + /* Retrieve device ID from requestor ID using parent device */ + ret = of_map_id(parent->of_node, cdx_dev->req_id, "msi-map", + "msi-map-mask", NULL, &dev_id); + if (ret) { + dev_err(dev, "of_map_id failed for MSI: %d\n", ret); + return ret; + } + + /* Set the device Id to be passed to the GIC-ITS */ + info->scratchpad[0].ul = dev_id; + + msi_info = msi_get_domain_info(msi_domain->parent); + + /* Allocate at least 32 MSIs, and always as a power of 2 */ + nvec = max_t(int, 32, roundup_pow_of_two(nvec)); + return msi_info->ops->msi_prepare(msi_domain->parent, dev, nvec, info); +} + +static struct msi_domain_ops cdx_msi_ops __ro_after_init = { + .msi_prepare = cdx_msi_prepare, +}; + +static struct msi_domain_info cdx_msi_domain_info = { + .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS), + .ops = &cdx_msi_ops, + .chip = &cdx_msi_irq_chip, +}; + +struct irq_domain *cdx_msi_domain_init(struct device *dev) +{ + struct irq_domain *parent; + struct irq_domain *cdx_msi_domain; + struct fwnode_handle *fwnode_handle; + struct device_node *parent_node; + struct device_node *np = dev->of_node; + + fwnode_handle = of_node_to_fwnode(np); + + parent_node = of_parse_phandle(np, "msi-map", 1); + if (!parent_node) { + dev_err(dev, "msi-map not present on cdx controller\n"); + return NULL; + } + + parent = irq_find_matching_fwnode(of_node_to_fwnode(parent_node), + DOMAIN_BUS_NEXUS); + if (!parent || !msi_get_domain_info(parent)) { + dev_err(dev, "unable to locate ITS domain\n"); + return NULL; + } + + cdx_msi_domain = cdx_msi_create_irq_domain(fwnode_handle, + &cdx_msi_domain_info, parent); + if (!cdx_msi_domain) { + dev_err(dev, "unable to create CDX-MSI domain\n"); + return NULL; + } + + dev_dbg(dev, "CDX-MSI domain created\n"); + + return cdx_msi_domain; +} + +struct irq_domain *cdx_find_msi_domain(struct device *parent) +{ + return irq_find_host(parent->of_node); +} diff --git a/drivers/bus/cdx/mcdi_stubs.c b/drivers/bus/cdx/mcdi_stubs.c index cc9d30fa02f8..2c8db1f5a057 100644 --- a/drivers/bus/cdx/mcdi_stubs.c +++ b/drivers/bus/cdx/mcdi_stubs.c @@ -45,6 +45,7 @@ int cdx_mcdi_get_func_config(struct cdx_mcdi_t *cdx_mcdi, dev_params->res_count = 2; dev_params->req_id = 0x250; + dev_params->num_msi = 4; dev_params->vendor = 0x10ee; dev_params->device = 0x8084; dev_params->bus_id = bus_id; diff --git a/include/linux/cdx/cdx_bus.h b/include/linux/cdx/cdx_bus.h index 6e870b2c87d9..bf86024783d2 100644 --- a/include/linux/cdx/cdx_bus.h +++ b/include/linux/cdx/cdx_bus.h @@ -25,6 +25,7 @@ * @dma_mask: Default DMA mask * @flags: CDX device flags * @req_id: Requestor ID associated with CDX device + * @num_msi: Number of MSI's supported by the device * @driver_override: driver name to force a match; do not set directly, * because core frees it; use driver_set_override() to * set or clear it. @@ -40,6 +41,7 @@ struct cdx_device { u64 dma_mask; u16 flags; u32 req_id; + u32 num_msi; const char *driver_override; }; @@ -90,4 +92,21 @@ void cdx_driver_unregister(struct cdx_driver *driver); extern struct bus_type cdx_bus_type; +/** + * cdx_msi_domain_alloc_irqs - Allocate MSI's for the CDX device + * @dev: device pointer + * @irq_count: Number of MSI's to be allocated + * + * Return 0 for success, -errno on failure + */ +int cdx_msi_domain_alloc_irqs(struct device *dev, unsigned int irq_count); + +/** + * cdx_msi_domain_free_irqs - Free MSI's for CDX device + * @dev: device pointer + * + * Return 0 for success, -errno on failure + */ +void cdx_msi_domain_free_irqs(struct device *dev); + #endif /* _CDX_BUS_H_ */ -- 2.25.1