Since CDX 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/Kconfig | 1 + drivers/bus/cdx/Makefile | 2 +- drivers/bus/cdx/cdx.c | 18 ++++ drivers/bus/cdx/cdx.h | 10 +++ drivers/bus/cdx/cdx_msi.c | 161 ++++++++++++++++++++++++++++++++++++ include/linux/cdx/cdx_bus.h | 26 ++++++ kernel/irq/msi.c | 1 + 7 files changed, 218 insertions(+), 1 deletion(-) create mode 100644 drivers/bus/cdx/cdx_msi.c diff --git a/drivers/bus/cdx/Kconfig b/drivers/bus/cdx/Kconfig index 98ec05ad708d..062443080d6f 100644 --- a/drivers/bus/cdx/Kconfig +++ b/drivers/bus/cdx/Kconfig @@ -7,6 +7,7 @@ config CDX_BUS bool "CDX Bus driver" + select GENERIC_MSI_IRQ_DOMAIN help Driver to enable CDX Bus infrastructure. CDX bus uses CDX controller and firmware to scan the FPGA based diff --git a/drivers/bus/cdx/Makefile b/drivers/bus/cdx/Makefile index 2e8f42611dfc..95f8fa3b4db8 100644 --- a/drivers/bus/cdx/Makefile +++ b/drivers/bus/cdx/Makefile @@ -5,4 +5,4 @@ # Copyright (C) 2022, Advanced Micro Devices, Inc. # -obj-$(CONFIG_CDX_BUS) += cdx.o +obj-$(CONFIG_CDX_BUS) += cdx.o cdx_msi.o diff --git a/drivers/bus/cdx/cdx.c b/drivers/bus/cdx/cdx.c index 41c61bf6d5f0..a3accde0421f 100644 --- a/drivers/bus/cdx/cdx.c +++ b/drivers/bus/cdx/cdx.c @@ -56,6 +56,7 @@ */ #include <linux/init.h> +#include <linux/irqdomain.h> #include <linux/kernel.h> #include <linux/of_device.h> #include <linux/slab.h> @@ -449,6 +450,7 @@ int cdx_device_add(struct cdx_dev_params_t *dev_params) struct cdx_controller_t *cdx = dev_params->cdx; struct device *parent = cdx->dev; struct cdx_device *cdx_dev; + struct irq_domain *cdx_msi_domain; int ret; cdx_dev = kzalloc(sizeof(*cdx_dev), GFP_KERNEL); @@ -465,6 +467,7 @@ int cdx_device_add(struct cdx_dev_params_t *dev_params) /* 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_num = dev_params->bus_num; @@ -483,6 +486,21 @@ int cdx_device_add(struct cdx_dev_params_t *dev_params) dev_set_name(&cdx_dev->dev, "cdx-%02x:%02x", cdx_dev->bus_num, cdx_dev->dev_num); + /* If CDX MSI domain is not created, create one. */ + cdx_msi_domain = irq_find_host(parent->of_node); + 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 -ENODEV; + } + } + + /* 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 80496865ae9c..5fd40c7e633e 100644 --- a/drivers/bus/cdx/cdx.h +++ b/drivers/bus/cdx/cdx.h @@ -23,6 +23,7 @@ * @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 { struct cdx_controller_t *cdx; @@ -35,6 +36,7 @@ struct cdx_dev_params_t { struct resource res[MAX_CDX_DEV_RESOURCES]; u8 res_count; u32 req_id; + u32 num_msi; }; /** @@ -63,4 +65,12 @@ void cdx_unregister_controller(struct cdx_controller_t *cdx); */ int cdx_device_add(struct cdx_dev_params_t *dev_params); +/** + * 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); + #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..b9e7e9d6fb51 --- /dev/null +++ b/drivers/bus/cdx/cdx_msi.c @@ -0,0 +1,161 @@ +// 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" + +#define REQ_ID_SHIFT 10 + +/* + * Convert an msi_desc to a globaly unique identifier (per-device + * reqid + msi_desc position in the msi_list). + */ +static irq_hw_number_t cdx_domain_calc_hwirq(struct cdx_device *dev, + struct msi_desc *desc) +{ + return (dev->req_id << REQ_ID_SHIFT) | desc->msi_index; +} + +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); +} + +static void cdx_msi_write_msg(struct irq_data *irq_data, + struct msi_msg *msg) +{ + struct msi_desc *msi_desc = irq_data_get_msi_desc(irq_data); + struct cdx_device *cdx_dev = to_cdx_device(msi_desc->dev); + struct cdx_controller_t *cdx = cdx_dev->cdx; + uint64_t addr; + int ret; + + addr = ((uint64_t)(msi_desc->msg.address_hi) << 32) | + msi_desc->msg.address_lo; + + ret = cdx->ops.write_msi(cdx, cdx_dev->bus_num, cdx_dev->dev_num, + msi_desc->msi_index, msi_desc->msg.data, + addr); + if (ret) + dev_err(&cdx_dev->dev, "Write MSI failed to CDX controller\n"); +} + +int cdx_msi_domain_alloc_irqs(struct device *dev, unsigned int irq_count) +{ + int ret; + + ret = msi_setup_device_data(dev); + if (ret) + return ret; + + msi_lock_descs(dev); + if (msi_first_desc(dev, MSI_DESC_ALL)) + ret = -EINVAL; + msi_unlock_descs(dev); + if (ret) + return ret; + + ret = msi_domain_alloc_irqs(dev, irq_count); + if (ret) + dev_err(dev, "Failed to allocate IRQs\n"); + + return ret; +} +EXPORT_SYMBOL_GPL(cdx_msi_domain_alloc_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, + .irq_write_msi_msg = cdx_msi_write_msg +}; + +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); + + 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, + .set_desc = cdx_msi_set_desc +}; + +static struct msi_domain_info cdx_msi_domain_info = { + .ops = &cdx_msi_ops, + .chip = &cdx_msi_irq_chip, + .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS | + MSI_FLAG_ALLOC_SIMPLE_MSI_DESCS | MSI_FLAG_FREE_MSI_DESCS +}; + +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 = 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; +} diff --git a/include/linux/cdx/cdx_bus.h b/include/linux/cdx/cdx_bus.h index 9e6872a03215..dfc0bd289834 100644 --- a/include/linux/cdx/cdx_bus.h +++ b/include/linux/cdx/cdx_bus.h @@ -21,14 +21,21 @@ typedef int (*cdx_scan_t)(struct cdx_controller_t *cdx); typedef int (*cdx_dev_reset_t)(struct cdx_controller_t *cdx, uint8_t bus_num, uint8_t dev_num); +typedef int (*cdx_write_msi_msg_t)(struct cdx_controller_t *cdx, + uint8_t bus_num, uint8_t dev_num, + uint16_t msi_index, uint32_t data, + uint64_t addr); + /** * Callbacks supported by CDX controller. * @scan: scan the devices on the controller * @reset_dev: reset a CDX device + * @write_msi: callback to write the MSI message */ struct cdx_ops_t { cdx_scan_t scan; cdx_dev_reset_t reset_dev; + cdx_write_msi_msg_t write_msi; }; /** @@ -57,6 +64,7 @@ struct cdx_controller_t { * @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. @@ -73,6 +81,7 @@ struct cdx_device { u64 dma_mask; u16 flags; u32 req_id; + u32 num_msi; const char *driver_override; }; @@ -136,4 +145,21 @@ extern struct bus_type cdx_bus_type; */ int cdx_dev_reset(struct device *dev); +/** + * 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 + */ +#define cdx_msi_domain_free_irqs msi_domain_free_irqs + #endif /* _CDX_BUS_H_ */ diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c index 14983c82a9e3..f55a5e395686 100644 --- a/kernel/irq/msi.c +++ b/kernel/irq/msi.c @@ -1034,6 +1034,7 @@ void msi_domain_free_irqs(struct device *dev) msi_domain_free_irqs_descs_locked(dev); msi_unlock_descs(dev); } +EXPORT_SYMBOL_GPL(msi_domain_free_irqs); /** * msi_get_domain_info - Get the MSI interrupt domain info for @domain -- 2.25.1