--- /dev/null
+/*
+ * Freescale Management Complex (MC) bus driver MSI support
+ *
+ * Copyright (C) 2015 Freescale Semiconductor, Inc.
+ * Author: German Rivera <German.Rivera@freescale.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/of_device.h>
+#include <linux/of_address.h>
+#include <linux/irqchip/arm-gic-v3.h>
+#include <linux/of_irq.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/msi.h>
+#include "../include/mc-bus.h"
+
+/*
+ * Generate a unique ID identifying the interrupt (only used within the MSI
+ * irqdomain. Combine the icid with the interrupt index.
+ */
+static irq_hw_number_t fsl_mc_domain_calc_hwirq(struct fsl_mc_device *dev,
+ struct msi_desc *desc)
+{
+ /*
+ * Make the base hwirq value for ICID*10000 so it is readable
+ * as a decimal value in /proc/interrupts.
+ */
+ return (irq_hw_number_t)(desc->fsl_mc.msi_index + (dev->icid * 10000));
+}
+
+static void fsl_mc_msi_set_desc(msi_alloc_info_t *arg,
+ struct msi_desc *desc)
+{
+ arg->desc = desc;
+ arg->hwirq = fsl_mc_domain_calc_hwirq(to_fsl_mc_device(desc->dev),
+ desc);
+}
+
+static void fsl_mc_msi_update_dom_ops(struct msi_domain_info *info)
+{
+ struct msi_domain_ops *ops = info->ops;
+
+ if (WARN_ON(!ops))
+ return;
+
+ /*
+ * set_desc should not be set by the caller
+ */
+ if (ops->set_desc == NULL)
+ ops->set_desc = fsl_mc_msi_set_desc;
+}
+
+static void __fsl_mc_msi_write_msg(struct fsl_mc_device *mc_bus_dev,
+ struct fsl_mc_device_irq *mc_dev_irq)
+{
+ int error;
+ struct fsl_mc_device *owner_mc_dev = mc_dev_irq->mc_dev;
+ struct msi_desc *msi_desc = mc_dev_irq->msi_desc;
+ struct dprc_irq_cfg irq_cfg;
+
+ /*
+ * msi_desc->msg.address is 0x0 when this function is invoked in
+ * the free_irq() code path. In this case, for the MC, we don't
+ * really need to "unprogram" the MSI, so we just return.
+ */
+ if (msi_desc->msg.address_lo == 0x0 && msi_desc->msg.address_hi == 0x0)
+ return;
+
+ if (WARN_ON(!owner_mc_dev))
+ return;
+
+ irq_cfg.paddr = ((u64)msi_desc->msg.address_hi << 32) |
+ msi_desc->msg.address_lo;
+ irq_cfg.val = msi_desc->msg.data;
+ irq_cfg.irq_num = msi_desc->irq;
+
+ if (owner_mc_dev == mc_bus_dev) {
+ /*
+ * IRQ is for the mc_bus_dev's DPRC itself
+ */
+ error = dprc_set_irq(mc_bus_dev->mc_io,
+ MC_CMD_FLAG_INTR_DIS | MC_CMD_FLAG_PRI,
+ mc_bus_dev->mc_handle,
+ mc_dev_irq->dev_irq_index,
+ &irq_cfg);
+ if (error < 0) {
+ dev_err(&owner_mc_dev->dev,
+ "dprc_set_irq() failed: %d\n", error);
+ }
+ } else {
+ /*
+ * IRQ is for for a child device of mc_bus_dev
+ */
+ error = dprc_set_obj_irq(mc_bus_dev->mc_io,
+ MC_CMD_FLAG_INTR_DIS | MC_CMD_FLAG_PRI,
+ mc_bus_dev->mc_handle,
+ owner_mc_dev->obj_desc.type,
+ owner_mc_dev->obj_desc.id,
+ mc_dev_irq->dev_irq_index,
+ &irq_cfg);
+ if (error < 0) {
+ dev_err(&owner_mc_dev->dev,
+ "dprc_obj_set_irq() failed: %d\n", error);
+ }
+ }
+}
+
+/*
+ * NOTE: This function is invoked with interrupts disabled
+ */
+static void fsl_mc_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 fsl_mc_device *mc_bus_dev = to_fsl_mc_device(msi_desc->dev);
+ struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
+ struct fsl_mc_device_irq *mc_dev_irq =
+ &mc_bus->irq_resources[msi_desc->fsl_mc.msi_index];
+
+ WARN_ON(mc_dev_irq->msi_desc != msi_desc);
+ msi_desc->msg = *msg;
+
+ /*
+ * Program the MSI (paddr, value) pair in the device:
+ */
+ __fsl_mc_msi_write_msg(mc_bus_dev, mc_dev_irq);
+}
+
+static void fsl_mc_msi_update_chip_ops(struct msi_domain_info *info)
+{
+ struct irq_chip *chip = info->chip;
+
+ if (WARN_ON((!chip)))
+ return;
+
+ /*
+ * irq_write_msi_msg should not be set by the caller
+ */
+ if (chip->irq_write_msi_msg == NULL)
+ chip->irq_write_msi_msg = fsl_mc_msi_write_msg;
+}
+
+/**
+ * fsl_mc_msi_create_irq_domain - Create a fsl-mc MSI interrupt domain
+ * @np: Optional device-tree node of the interrupt controller
+ * @info: MSI domain info
+ * @parent: Parent irq domain
+ *
+ * Updates the domain and chip ops and creates a fsl-mc MSI
+ * interrupt domain.
+ *
+ * Returns:
+ * A domain pointer or NULL in case of failure.
+ */
+struct irq_domain *fsl_mc_msi_create_irq_domain(struct fwnode_handle *fwnode,
+ struct msi_domain_info *info,
+ struct irq_domain *parent)
+{
+ struct irq_domain *domain;
+
+ if (info->flags & MSI_FLAG_USE_DEF_DOM_OPS)
+ fsl_mc_msi_update_dom_ops(info);
+ if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS)
+ fsl_mc_msi_update_chip_ops(info);
+
+ domain = msi_create_irq_domain(fwnode, info, parent);
+ if (domain)
+ domain->bus_token = DOMAIN_BUS_FSL_MC_MSI;
+
+ return domain;
+}
+
+int fsl_mc_find_msi_domain(struct device *mc_platform_dev,
+ struct irq_domain **mc_msi_domain)
+{
+ struct irq_domain *msi_domain;
+ struct device_node *mc_of_node = mc_platform_dev->of_node;
+
+ msi_domain = of_msi_get_domain(mc_platform_dev, mc_of_node,
+ DOMAIN_BUS_FSL_MC_MSI);
+ if (!msi_domain) {
+ pr_err("Unable to find fsl-mc MSI domain for %s\n",
+ mc_of_node->full_name);
+
+ return -ENOENT;
+ }
+
+ *mc_msi_domain = msi_domain;
+ return 0;
+}
+
+static void fsl_mc_msi_free_descs(struct device *dev)
+{
+ struct msi_desc *desc, *tmp;
+
+ list_for_each_entry_safe(desc, tmp, dev_to_msi_list(dev), list) {
+ list_del(&desc->list);
+ free_msi_entry(desc);
+ }
+}
+
+static int fsl_mc_msi_alloc_descs(struct device *dev, unsigned int irq_count)
+
+{
+ unsigned int i;
+ int error;
+ struct msi_desc *msi_desc;
+
+ for (i = 0; i < irq_count; i++) {
+ msi_desc = alloc_msi_entry(dev);
+ if (!msi_desc) {
+ dev_err(dev, "Failed to allocate msi entry\n");
+ error = -ENOMEM;
+ goto cleanup_msi_descs;
+ }
+
+ msi_desc->fsl_mc.msi_index = i;
+ msi_desc->nvec_used = 1;
+ INIT_LIST_HEAD(&msi_desc->list);
+ list_add_tail(&msi_desc->list, dev_to_msi_list(dev));
+ }
+
+ return 0;
+
+cleanup_msi_descs:
+ fsl_mc_msi_free_descs(dev);
+ return error;
+}
+
+int fsl_mc_msi_domain_alloc_irqs(struct device *dev,
+ unsigned int irq_count)
+{
+ struct irq_domain *msi_domain;
+ int error;
+
+ if (WARN_ON(!list_empty(dev_to_msi_list(dev))))
+ return -EINVAL;
+
+ error = fsl_mc_msi_alloc_descs(dev, irq_count);
+ if (error < 0)
+ return error;
+
+ msi_domain = dev_get_msi_domain(dev);
+ if (WARN_ON(!msi_domain)) {
+ error = -EINVAL;
+ goto cleanup_msi_descs;
+ }
+
+ /*
+ * NOTE: Calling this function will trigger the invocation of the
+ * its_fsl_mc_msi_prepare() callback
+ */
+ error = msi_domain_alloc_irqs(msi_domain, dev, irq_count);
+
+ if (error) {
+ dev_err(dev, "Failed to allocate IRQs\n");
+ goto cleanup_msi_descs;
+ }
+
+ return 0;
+
+cleanup_msi_descs:
+ fsl_mc_msi_free_descs(dev);
+ return error;
+}
+
+void fsl_mc_msi_domain_free_irqs(struct device *dev)
+{
+ struct irq_domain *msi_domain;
+
+ msi_domain = dev_get_msi_domain(dev);
+ if (WARN_ON(!msi_domain))
+ return;
+
+ msi_domain_free_irqs(msi_domain, dev);
+
+ if (WARN_ON(list_empty(dev_to_msi_list(dev))))
+ return;
+
+ fsl_mc_msi_free_descs(dev);
+}
projects / deliverable / linux.git / blobdiff