Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 410 insertions, 0 deletions

diff --git a/drivers/base/platform-msi.c b/drivers/base/platform-msi.c
new file mode 100644
index 000000000..6d54905c6
--- /dev/null
+++ b/drivers/base/platform-msi.c
@@ -0,0 +1,410 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * MSI framework for platform devices
+ *
+ * Copyright (C) 2015 ARM Limited, All Rights Reserved.
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ */
+
+#include <linux/device.h>
+#include <linux/idr.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/msi.h>
+#include <linux/slab.h>
+
+#define DEV_ID_SHIFT	21
+#define MAX_DEV_MSIS	(1 << (32 - DEV_ID_SHIFT))
+
+/*
+ * Internal data structure containing a (made up, but unique) devid
+ * and the callback to write the MSI message.
+ */
+struct platform_msi_priv_data {
+	struct device		*dev;
+	void 			*host_data;
+	msi_alloc_info_t	arg;
+	irq_write_msi_msg_t	write_msg;
+	int			devid;
+};
+
+/* The devid allocator */
+static DEFINE_IDA(platform_msi_devid_ida);
+
+#ifdef GENERIC_MSI_DOMAIN_OPS
+/*
+ * Convert an msi_desc to a globaly unique identifier (per-device
+ * devid + msi_desc position in the msi_list).
+ */
+static irq_hw_number_t platform_msi_calc_hwirq(struct msi_desc *desc)
+{
+	u32 devid;
+
+	devid = desc->platform.msi_priv_data->devid;
+
+	return (devid << (32 - DEV_ID_SHIFT)) | desc->platform.msi_index;
+}
+
+static void platform_msi_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc)
+{
+	arg->desc = desc;
+	arg->hwirq = platform_msi_calc_hwirq(desc);
+}
+
+static int platform_msi_init(struct irq_domain *domain,
+			     struct msi_domain_info *info,
+			     unsigned int virq, irq_hw_number_t hwirq,
+			     msi_alloc_info_t *arg)
+{
+	return irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
+					     info->chip, info->chip_data);
+}
+#else
+#define platform_msi_set_desc		NULL
+#define platform_msi_init		NULL
+#endif
+
+static void platform_msi_update_dom_ops(struct msi_domain_info *info)
+{
+	struct msi_domain_ops *ops = info->ops;
+
+	BUG_ON(!ops);
+
+	if (ops->msi_init == NULL)
+		ops->msi_init = platform_msi_init;
+	if (ops->set_desc == NULL)
+		ops->set_desc = platform_msi_set_desc;
+}
+
+static void platform_msi_write_msg(struct irq_data *data, struct msi_msg *msg)
+{
+	struct msi_desc *desc = irq_data_get_msi_desc(data);
+	struct platform_msi_priv_data *priv_data;
+
+	priv_data = desc->platform.msi_priv_data;
+
+	priv_data->write_msg(desc, msg);
+}
+
+static void platform_msi_update_chip_ops(struct msi_domain_info *info)
+{
+	struct irq_chip *chip = info->chip;
+
+	BUG_ON(!chip);
+	if (!chip->irq_mask)
+		chip->irq_mask = irq_chip_mask_parent;
+	if (!chip->irq_unmask)
+		chip->irq_unmask = irq_chip_unmask_parent;
+	if (!chip->irq_eoi)
+		chip->irq_eoi = irq_chip_eoi_parent;
+	if (!chip->irq_set_affinity)
+		chip->irq_set_affinity = msi_domain_set_affinity;
+	if (!chip->irq_write_msi_msg)
+		chip->irq_write_msi_msg = platform_msi_write_msg;
+	if (WARN_ON((info->flags & MSI_FLAG_LEVEL_CAPABLE) &&
+		    !(chip->flags & IRQCHIP_SUPPORTS_LEVEL_MSI)))
+		info->flags &= ~MSI_FLAG_LEVEL_CAPABLE;
+}
+
+static void platform_msi_free_descs(struct device *dev, int base, int nvec)
+{
+	struct msi_desc *desc, *tmp;
+
+	list_for_each_entry_safe(desc, tmp, dev_to_msi_list(dev), list) {
+		if (desc->platform.msi_index >= base &&
+		    desc->platform.msi_index < (base + nvec)) {
+			list_del(&desc->list);
+			free_msi_entry(desc);
+		}
+	}
+}
+
+static int platform_msi_alloc_descs_with_irq(struct device *dev, int virq,
+					     int nvec,
+					     struct platform_msi_priv_data *data)
+
+{
+	struct msi_desc *desc;
+	int i, base = 0;
+
+	if (!list_empty(dev_to_msi_list(dev))) {
+		desc = list_last_entry(dev_to_msi_list(dev),
+				       struct msi_desc, list);
+		base = desc->platform.msi_index + 1;
+	}
+
+	for (i = 0; i < nvec; i++) {
+		desc = alloc_msi_entry(dev, 1, NULL);
+		if (!desc)
+			break;
+
+		desc->platform.msi_priv_data = data;
+		desc->platform.msi_index = base + i;
+		desc->irq = virq ? virq + i : 0;
+
+		list_add_tail(&desc->list, dev_to_msi_list(dev));
+	}
+
+	if (i != nvec) {
+		/* Clean up the mess */
+		platform_msi_free_descs(dev, base, nvec);
+
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static int platform_msi_alloc_descs(struct device *dev, int nvec,
+				    struct platform_msi_priv_data *data)
+
+{
+	return platform_msi_alloc_descs_with_irq(dev, 0, nvec, data);
+}
+
+/**
+ * platform_msi_create_irq_domain - Create a platform MSI interrupt domain
+ * @fwnode:		Optional fwnode of the interrupt controller
+ * @info:	MSI domain info
+ * @parent:	Parent irq domain
+ *
+ * Updates the domain and chip ops and creates a platform MSI
+ * interrupt domain.
+ *
+ * Returns:
+ * A domain pointer or NULL in case of failure.
+ */
+struct irq_domain *platform_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)
+		platform_msi_update_dom_ops(info);
+	if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS)
+		platform_msi_update_chip_ops(info);
+
+	domain = msi_create_irq_domain(fwnode, info, parent);
+	if (domain)
+		irq_domain_update_bus_token(domain, DOMAIN_BUS_PLATFORM_MSI);
+
+	return domain;
+}
+
+static struct platform_msi_priv_data *
+platform_msi_alloc_priv_data(struct device *dev, unsigned int nvec,
+			     irq_write_msi_msg_t write_msi_msg)
+{
+	struct platform_msi_priv_data *datap;
+	/*
+	 * Limit the number of interrupts to 2048 per device. Should we
+	 * need to bump this up, DEV_ID_SHIFT should be adjusted
+	 * accordingly (which would impact the max number of MSI
+	 * capable devices).
+	 */
+	if (!dev->msi_domain || !write_msi_msg || !nvec || nvec > MAX_DEV_MSIS)
+		return ERR_PTR(-EINVAL);
+
+	if (dev->msi_domain->bus_token != DOMAIN_BUS_PLATFORM_MSI) {
+		dev_err(dev, "Incompatible msi_domain, giving up\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	/* Already had a helping of MSI? Greed... */
+	if (!list_empty(dev_to_msi_list(dev)))
+		return ERR_PTR(-EBUSY);
+
+	datap = kzalloc(sizeof(*datap), GFP_KERNEL);
+	if (!datap)
+		return ERR_PTR(-ENOMEM);
+
+	datap->devid = ida_simple_get(&platform_msi_devid_ida,
+				      0, 1 << DEV_ID_SHIFT, GFP_KERNEL);
+	if (datap->devid < 0) {
+		int err = datap->devid;
+		kfree(datap);
+		return ERR_PTR(err);
+	}
+
+	datap->write_msg = write_msi_msg;
+	datap->dev = dev;
+
+	return datap;
+}
+
+static void platform_msi_free_priv_data(struct platform_msi_priv_data *data)
+{
+	ida_simple_remove(&platform_msi_devid_ida, data->devid);
+	kfree(data);
+}
+
+/**
+ * platform_msi_domain_alloc_irqs - Allocate MSI interrupts for @dev
+ * @dev:		The device for which to allocate interrupts
+ * @nvec:		The number of interrupts to allocate
+ * @write_msi_msg:	Callback to write an interrupt message for @dev
+ *
+ * Returns:
+ * Zero for success, or an error code in case of failure
+ */
+int platform_msi_domain_alloc_irqs(struct device *dev, unsigned int nvec,
+				   irq_write_msi_msg_t write_msi_msg)
+{
+	struct platform_msi_priv_data *priv_data;
+	int err;
+
+	priv_data = platform_msi_alloc_priv_data(dev, nvec, write_msi_msg);
+	if (IS_ERR(priv_data))
+		return PTR_ERR(priv_data);
+
+	err = platform_msi_alloc_descs(dev, nvec, priv_data);
+	if (err)
+		goto out_free_priv_data;
+
+	err = msi_domain_alloc_irqs(dev->msi_domain, dev, nvec);
+	if (err)
+		goto out_free_desc;
+
+	return 0;
+
+out_free_desc:
+	platform_msi_free_descs(dev, 0, nvec);
+out_free_priv_data:
+	platform_msi_free_priv_data(priv_data);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(platform_msi_domain_alloc_irqs);
+
+/**
+ * platform_msi_domain_free_irqs - Free MSI interrupts for @dev
+ * @dev:	The device for which to free interrupts
+ */
+void platform_msi_domain_free_irqs(struct device *dev)
+{
+	if (!list_empty(dev_to_msi_list(dev))) {
+		struct msi_desc *desc;
+
+		desc = first_msi_entry(dev);
+		platform_msi_free_priv_data(desc->platform.msi_priv_data);
+	}
+
+	msi_domain_free_irqs(dev->msi_domain, dev);
+	platform_msi_free_descs(dev, 0, MAX_DEV_MSIS);
+}
+EXPORT_SYMBOL_GPL(platform_msi_domain_free_irqs);
+
+/**
+ * platform_msi_get_host_data - Query the private data associated with
+ *                              a platform-msi domain
+ * @domain:	The platform-msi domain
+ *
+ * Returns the private data provided when calling
+ * platform_msi_create_device_domain.
+ */
+void *platform_msi_get_host_data(struct irq_domain *domain)
+{
+	struct platform_msi_priv_data *data = domain->host_data;
+	return data->host_data;
+}
+
+/**
+ * platform_msi_create_device_domain - Create a platform-msi domain
+ *
+ * @dev:		The device generating the MSIs
+ * @nvec:		The number of MSIs that need to be allocated
+ * @write_msi_msg:	Callback to write an interrupt message for @dev
+ * @ops:		The hierarchy domain operations to use
+ * @host_data:		Private data associated to this domain
+ *
+ * Returns an irqdomain for @nvec interrupts
+ */
+struct irq_domain *
+platform_msi_create_device_domain(struct device *dev,
+				  unsigned int nvec,
+				  irq_write_msi_msg_t write_msi_msg,
+				  const struct irq_domain_ops *ops,
+				  void *host_data)
+{
+	struct platform_msi_priv_data *data;
+	struct irq_domain *domain;
+	int err;
+
+	data = platform_msi_alloc_priv_data(dev, nvec, write_msi_msg);
+	if (IS_ERR(data))
+		return NULL;
+
+	data->host_data = host_data;
+	domain = irq_domain_create_hierarchy(dev->msi_domain, 0, nvec,
+					     dev->fwnode, ops, data);
+	if (!domain)
+		goto free_priv;
+
+	err = msi_domain_prepare_irqs(domain->parent, dev, nvec, &data->arg);
+	if (err)
+		goto free_domain;
+
+	return domain;
+
+free_domain:
+	irq_domain_remove(domain);
+free_priv:
+	platform_msi_free_priv_data(data);
+	return NULL;
+}
+
+/**
+ * platform_msi_domain_free - Free interrupts associated with a platform-msi
+ *                            domain
+ *
+ * @domain:	The platform-msi domain
+ * @virq:	The base irq from which to perform the free operation
+ * @nvec:	How many interrupts to free from @virq
+ */
+void platform_msi_domain_free(struct irq_domain *domain, unsigned int virq,
+			      unsigned int nvec)
+{
+	struct platform_msi_priv_data *data = domain->host_data;
+	struct msi_desc *desc, *tmp;
+	for_each_msi_entry_safe(desc, tmp, data->dev) {
+		if (WARN_ON(!desc->irq || desc->nvec_used != 1))
+			return;
+		if (!(desc->irq >= virq && desc->irq < (virq + nvec)))
+			continue;
+
+		irq_domain_free_irqs_common(domain, desc->irq, 1);
+		list_del(&desc->list);
+		free_msi_entry(desc);
+	}
+}
+
+/**
+ * platform_msi_domain_alloc - Allocate interrupts associated with
+ *			       a platform-msi domain
+ *
+ * @domain:	The platform-msi domain
+ * @virq:	The base irq from which to perform the allocate operation
+ * @nvec:	How many interrupts to free from @virq
+ *
+ * Return 0 on success, or an error code on failure. Must be called
+ * with irq_domain_mutex held (which can only be done as part of a
+ * top-level interrupt allocation).
+ */
+int platform_msi_domain_alloc(struct irq_domain *domain, unsigned int virq,
+			      unsigned int nr_irqs)
+{
+	struct platform_msi_priv_data *data = domain->host_data;
+	int err;
+
+	err = platform_msi_alloc_descs_with_irq(data->dev, virq, nr_irqs, data);
+	if (err)
+		return err;
+
+	err = msi_domain_populate_irqs(domain->parent, data->dev,
+				       virq, nr_irqs, &data->arg);
+	if (err)
+		platform_msi_domain_free(domain, virq, nr_irqs);
+
+	return err;
+}