diff options
Diffstat (limited to 'drivers/misc/ocxl/afu_irq.c')
| -rw-r--r-- | drivers/misc/ocxl/afu_irq.c | 212 |
1 files changed, 212 insertions, 0 deletions
diff --git a/drivers/misc/ocxl/afu_irq.c b/drivers/misc/ocxl/afu_irq.c new file mode 100644 index 000000000..a06920b7e --- /dev/null +++ b/drivers/misc/ocxl/afu_irq.c @@ -0,0 +1,212 @@ +// SPDX-License-Identifier: GPL-2.0+ +// Copyright 2017 IBM Corp. +#include <linux/interrupt.h> +#include <linux/irqdomain.h> +#include <asm/pnv-ocxl.h> +#include <asm/xive.h> +#include "ocxl_internal.h" +#include "trace.h" + +struct afu_irq { + int id; + int hw_irq; + unsigned int virq; + char *name; + irqreturn_t (*handler)(void *private); + void (*free_private)(void *private); + void *private; +}; + +int ocxl_irq_offset_to_id(struct ocxl_context *ctx, u64 offset) +{ + return (offset - ctx->afu->irq_base_offset) >> PAGE_SHIFT; +} + +u64 ocxl_irq_id_to_offset(struct ocxl_context *ctx, int irq_id) +{ + return ctx->afu->irq_base_offset + (irq_id << PAGE_SHIFT); +} + +int ocxl_irq_set_handler(struct ocxl_context *ctx, int irq_id, + irqreturn_t (*handler)(void *private), + void (*free_private)(void *private), + void *private) +{ + struct afu_irq *irq; + int rc; + + mutex_lock(&ctx->irq_lock); + irq = idr_find(&ctx->irq_idr, irq_id); + if (!irq) { + rc = -EINVAL; + goto unlock; + } + + irq->handler = handler; + irq->private = private; + irq->free_private = free_private; + + rc = 0; + // Fall through to unlock + +unlock: + mutex_unlock(&ctx->irq_lock); + return rc; +} +EXPORT_SYMBOL_GPL(ocxl_irq_set_handler); + +static irqreturn_t afu_irq_handler(int virq, void *data) +{ + struct afu_irq *irq = (struct afu_irq *) data; + + trace_ocxl_afu_irq_receive(virq); + + if (irq->handler) + return irq->handler(irq->private); + + return IRQ_HANDLED; // Just drop it on the ground +} + +static int setup_afu_irq(struct ocxl_context *ctx, struct afu_irq *irq) +{ + int rc; + + irq->virq = irq_create_mapping(NULL, irq->hw_irq); + if (!irq->virq) { + pr_err("irq_create_mapping failed\n"); + return -ENOMEM; + } + pr_debug("hw_irq %d mapped to virq %u\n", irq->hw_irq, irq->virq); + + irq->name = kasprintf(GFP_KERNEL, "ocxl-afu-%u", irq->virq); + if (!irq->name) { + irq_dispose_mapping(irq->virq); + return -ENOMEM; + } + + rc = request_irq(irq->virq, afu_irq_handler, 0, irq->name, irq); + if (rc) { + kfree(irq->name); + irq->name = NULL; + irq_dispose_mapping(irq->virq); + pr_err("request_irq failed: %d\n", rc); + return rc; + } + return 0; +} + +static void release_afu_irq(struct afu_irq *irq) +{ + free_irq(irq->virq, irq); + irq_dispose_mapping(irq->virq); + kfree(irq->name); +} + +int ocxl_afu_irq_alloc(struct ocxl_context *ctx, int *irq_id) +{ + struct afu_irq *irq; + int rc; + + irq = kzalloc(sizeof(struct afu_irq), GFP_KERNEL); + if (!irq) + return -ENOMEM; + + /* + * We limit the number of afu irqs per context and per link to + * avoid a single process or user depleting the pool of IPIs + */ + + mutex_lock(&ctx->irq_lock); + + irq->id = idr_alloc(&ctx->irq_idr, irq, 0, MAX_IRQ_PER_CONTEXT, + GFP_KERNEL); + if (irq->id < 0) { + rc = -ENOSPC; + goto err_unlock; + } + + rc = ocxl_link_irq_alloc(ctx->afu->fn->link, &irq->hw_irq); + if (rc) + goto err_idr; + + rc = setup_afu_irq(ctx, irq); + if (rc) + goto err_alloc; + + trace_ocxl_afu_irq_alloc(ctx->pasid, irq->id, irq->virq, irq->hw_irq); + mutex_unlock(&ctx->irq_lock); + + *irq_id = irq->id; + + return 0; + +err_alloc: + ocxl_link_free_irq(ctx->afu->fn->link, irq->hw_irq); +err_idr: + idr_remove(&ctx->irq_idr, irq->id); +err_unlock: + mutex_unlock(&ctx->irq_lock); + kfree(irq); + return rc; +} +EXPORT_SYMBOL_GPL(ocxl_afu_irq_alloc); + +static void afu_irq_free(struct afu_irq *irq, struct ocxl_context *ctx) +{ + trace_ocxl_afu_irq_free(ctx->pasid, irq->id); + if (ctx->mapping) + unmap_mapping_range(ctx->mapping, + ocxl_irq_id_to_offset(ctx, irq->id), + 1 << PAGE_SHIFT, 1); + release_afu_irq(irq); + if (irq->free_private) + irq->free_private(irq->private); + ocxl_link_free_irq(ctx->afu->fn->link, irq->hw_irq); + kfree(irq); +} + +int ocxl_afu_irq_free(struct ocxl_context *ctx, int irq_id) +{ + struct afu_irq *irq; + + mutex_lock(&ctx->irq_lock); + + irq = idr_find(&ctx->irq_idr, irq_id); + if (!irq) { + mutex_unlock(&ctx->irq_lock); + return -EINVAL; + } + idr_remove(&ctx->irq_idr, irq->id); + afu_irq_free(irq, ctx); + mutex_unlock(&ctx->irq_lock); + return 0; +} +EXPORT_SYMBOL_GPL(ocxl_afu_irq_free); + +void ocxl_afu_irq_free_all(struct ocxl_context *ctx) +{ + struct afu_irq *irq; + int id; + + mutex_lock(&ctx->irq_lock); + idr_for_each_entry(&ctx->irq_idr, irq, id) + afu_irq_free(irq, ctx); + mutex_unlock(&ctx->irq_lock); +} + +u64 ocxl_afu_irq_get_addr(struct ocxl_context *ctx, int irq_id) +{ + struct xive_irq_data *xd; + struct afu_irq *irq; + u64 addr = 0; + + mutex_lock(&ctx->irq_lock); + irq = idr_find(&ctx->irq_idr, irq_id); + if (irq) { + xd = irq_get_handler_data(irq->virq); + addr = xd ? xd->trig_page : 0; + } + mutex_unlock(&ctx->irq_lock); + return addr; +} +EXPORT_SYMBOL_GPL(ocxl_afu_irq_get_addr); |