[PATCH 04/10] staging: fsl-mc: Extended MC bus allocator to include IRQs

From: J. German Rivera
Date: Mon Oct 26 2015 - 12:06:44 EST


All the IRQs for DPAA2 objects in the same DPRC must use
the ICID of that DPRC, as their device Id in the GIC-ITS.
Thus, all these IRQs must share the same ITT table in the GIC.
As a result, a pool of IRQs with the same device Id must be
preallocated per DPRC (fsl-mc bus instance). So, the fsl-mc
bus object allocator is extended to also provide services
to allocate IRQs to DPAA2 devices, from their parent fsl-mc bus
IRQ pool.

Signed-off-by: J. German Rivera <German.Rivera@xxxxxxxxxxxxx>
---
drivers/staging/fsl-mc/bus/mc-allocator.c | 199 ++++++++++++++++++++++++++++
drivers/staging/fsl-mc/include/mc-private.h | 15 +++
drivers/staging/fsl-mc/include/mc.h | 9 ++
3 files changed, 223 insertions(+)

diff --git a/drivers/staging/fsl-mc/bus/mc-allocator.c b/drivers/staging/fsl-mc/bus/mc-allocator.c
index 88d1857..6f1049a 100644
--- a/drivers/staging/fsl-mc/bus/mc-allocator.c
+++ b/drivers/staging/fsl-mc/bus/mc-allocator.c
@@ -15,6 +15,7 @@
#include "../include/dpcon-cmd.h"
#include "dpmcp-cmd.h"
#include "dpmcp.h"
+#include <linux/msi.h>

/**
* fsl_mc_resource_pool_add_device - add allocatable device to a resource
@@ -160,6 +161,7 @@ static const char *const fsl_mc_pool_type_strings[] = {
[FSL_MC_POOL_DPMCP] = "dpmcp",
[FSL_MC_POOL_DPBP] = "dpbp",
[FSL_MC_POOL_DPCON] = "dpcon",
+ [FSL_MC_POOL_IRQ] = "irq",
};

static int __must_check object_type_to_pool_type(const char *object_type,
@@ -465,6 +467,203 @@ void fsl_mc_object_free(struct fsl_mc_device *mc_adev)
}
EXPORT_SYMBOL_GPL(fsl_mc_object_free);

+/*
+ * Initialize the interrupt pool associated with a MC bus.
+ * It allocates a block of IRQs from the GIC-ITS
+ */
+int fsl_mc_populate_irq_pool(struct fsl_mc_bus *mc_bus,
+ unsigned int irq_count)
+{
+ unsigned int i;
+ struct msi_desc *msi_desc;
+ struct fsl_mc_device_irq *irq_resources;
+ struct fsl_mc_device_irq *mc_dev_irq;
+ int error;
+ struct fsl_mc_device *mc_bus_dev = &mc_bus->mc_dev;
+ struct fsl_mc_resource_pool *res_pool =
+ &mc_bus->resource_pools[FSL_MC_POOL_IRQ];
+
+ if (WARN_ON(irq_count == 0 ||
+ irq_count > FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS))
+ return -EINVAL;
+
+ error = fsl_mc_msi_domain_alloc_irqs(&mc_bus_dev->dev, irq_count);
+ if (error < 0)
+ return error;
+
+ irq_resources = devm_kzalloc(&mc_bus_dev->dev,
+ sizeof(*irq_resources) * irq_count,
+ GFP_KERNEL);
+ if (!irq_resources) {
+ error = -ENOMEM;
+ goto cleanup_msi_irqs;
+ }
+
+ for (i = 0; i < irq_count; i++) {
+ mc_dev_irq = &irq_resources[i];
+
+ /*
+ * NOTE: This mc_dev_irq's MSI addr/value pair will be set
+ * by the fsl_mc_msi_write_msg() callback
+ */
+ mc_dev_irq->resource.type = res_pool->type;
+ mc_dev_irq->resource.data = mc_dev_irq;
+ mc_dev_irq->resource.parent_pool = res_pool;
+ INIT_LIST_HEAD(&mc_dev_irq->resource.node);
+ list_add_tail(&mc_dev_irq->resource.node, &res_pool->free_list);
+ }
+
+ for_each_msi_entry(msi_desc, &mc_bus_dev->dev) {
+ mc_dev_irq = &irq_resources[msi_desc->msi_attrib.entry_nr];
+ mc_dev_irq->msi_desc = msi_desc;
+ mc_dev_irq->resource.id = msi_desc->irq;
+ }
+
+ res_pool->max_count = irq_count;
+ res_pool->free_count = irq_count;
+ mc_bus->irq_resources = irq_resources;
+ return 0;
+
+cleanup_msi_irqs:
+ fsl_mc_msi_domain_free_irqs(&mc_bus_dev->dev);
+ return error;
+}
+EXPORT_SYMBOL_GPL(fsl_mc_populate_irq_pool);
+
+/**
+ * Teardown the interrupt pool associated with an MC bus.
+ * It frees the IRQs that were allocated to the pool, back to the GIC-ITS.
+ */
+void fsl_mc_cleanup_irq_pool(struct fsl_mc_bus *mc_bus)
+{
+ struct fsl_mc_device *mc_bus_dev = &mc_bus->mc_dev;
+ struct fsl_mc_resource_pool *res_pool =
+ &mc_bus->resource_pools[FSL_MC_POOL_IRQ];
+
+ if (WARN_ON(!mc_bus->irq_resources))
+ return;
+
+ if (WARN_ON(res_pool->max_count == 0))
+ return;
+
+ if (WARN_ON(res_pool->free_count != res_pool->max_count))
+ return;
+
+ INIT_LIST_HEAD(&res_pool->free_list);
+ res_pool->max_count = 0;
+ res_pool->free_count = 0;
+ mc_bus->irq_resources = NULL;
+ fsl_mc_msi_domain_free_irqs(&mc_bus_dev->dev);
+}
+EXPORT_SYMBOL_GPL(fsl_mc_cleanup_irq_pool);
+
+/**
+ * It allocates the IRQs required by a given MC object device. The
+ * IRQs are allocated from the interrupt pool associated with the
+ * MC bus that contains the device, if the device is not a DPRC device.
+ * Otherwise, the IRQs are allocated from the interrupt pool associated
+ * with the MC bus that represents the DPRC device itself.
+ */
+int __must_check fsl_mc_allocate_irqs(struct fsl_mc_device *mc_dev)
+{
+ int i;
+ int irq_count;
+ int res_allocated_count = 0;
+ int error = -EINVAL;
+ struct fsl_mc_device_irq **irqs = NULL;
+ struct fsl_mc_bus *mc_bus;
+ struct fsl_mc_resource_pool *res_pool;
+
+ if (WARN_ON(mc_dev->irqs))
+ return -EINVAL;
+
+ irq_count = mc_dev->obj_desc.irq_count;
+ if (WARN_ON(irq_count == 0))
+ return -EINVAL;
+
+ if (strcmp(mc_dev->obj_desc.type, "dprc") == 0)
+ mc_bus = to_fsl_mc_bus(mc_dev);
+ else
+ mc_bus = to_fsl_mc_bus(to_fsl_mc_device(mc_dev->dev.parent));
+
+ if (WARN_ON(!mc_bus->irq_resources))
+ return -EINVAL;
+
+ res_pool = &mc_bus->resource_pools[FSL_MC_POOL_IRQ];
+ if (res_pool->free_count < irq_count) {
+ dev_err(&mc_dev->dev,
+ "Not able to allocate %u irqs for device\n", irq_count);
+ return -ENOSPC;
+ }
+
+ irqs = devm_kzalloc(&mc_dev->dev, irq_count * sizeof(irqs[0]),
+ GFP_KERNEL);
+ if (!irqs)
+ return -ENOMEM;
+
+ for (i = 0; i < irq_count; i++) {
+ struct fsl_mc_resource *resource;
+
+ error = fsl_mc_resource_allocate(mc_bus, FSL_MC_POOL_IRQ,
+ &resource);
+ if (error < 0)
+ goto error_resource_alloc;
+
+ irqs[i] = to_fsl_mc_irq(resource);
+ res_allocated_count++;
+
+ WARN_ON(irqs[i]->mc_dev);
+ irqs[i]->mc_dev = mc_dev;
+ irqs[i]->dev_irq_index = i;
+ }
+
+ mc_dev->irqs = irqs;
+ return 0;
+
+error_resource_alloc:
+ for (i = 0; i < res_allocated_count; i++) {
+ irqs[i]->mc_dev = NULL;
+ fsl_mc_resource_free(&irqs[i]->resource);
+ }
+
+ return error;
+}
+EXPORT_SYMBOL_GPL(fsl_mc_allocate_irqs);
+
+/*
+ * It frees the IRQs that were allocated for a MC object device, by
+ * returning them to the corresponding interrupt pool.
+ */
+void fsl_mc_free_irqs(struct fsl_mc_device *mc_dev)
+{
+ int i;
+ int irq_count;
+ struct fsl_mc_bus *mc_bus;
+ struct fsl_mc_device_irq **irqs = mc_dev->irqs;
+
+ if (WARN_ON(!irqs))
+ return;
+
+ irq_count = mc_dev->obj_desc.irq_count;
+
+ if (strcmp(mc_dev->obj_desc.type, "dprc") == 0)
+ mc_bus = to_fsl_mc_bus(mc_dev);
+ else
+ mc_bus = to_fsl_mc_bus(to_fsl_mc_device(mc_dev->dev.parent));
+
+ if (WARN_ON(!mc_bus->irq_resources))
+ return;
+
+ for (i = 0; i < irq_count; i++) {
+ WARN_ON(!irqs[i]->mc_dev);
+ irqs[i]->mc_dev = NULL;
+ fsl_mc_resource_free(&irqs[i]->resource);
+ }
+
+ mc_dev->irqs = NULL;
+}
+EXPORT_SYMBOL_GPL(fsl_mc_free_irqs);
+
/**
* fsl_mc_allocator_probe - callback invoked when an allocatable device is
* being added to the system
diff --git a/drivers/staging/fsl-mc/include/mc-private.h b/drivers/staging/fsl-mc/include/mc-private.h
index f2504bc..97295f0 100644
--- a/drivers/staging/fsl-mc/include/mc-private.h
+++ b/drivers/staging/fsl-mc/include/mc-private.h
@@ -30,6 +30,16 @@ struct irq_domain;
struct msi_domain_info;

/**
+ * Maximum number of total IRQs that can be pre-allocated for an MC bus'
+ * IRQ pool
+ */
+#define FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS 256
+
+struct device_node;
+struct irq_domain;
+struct msi_domain_info;
+
+/**
* struct fsl_mc - Private data of a "fsl,qoriq-mc" platform device
* @root_mc_bus_dev: MC object device representing the root DPRC
* @num_translation_ranges: number of entries in addr_translation_ranges
@@ -137,4 +147,9 @@ int __init its_fsl_mc_msi_init(void);

void its_fsl_mc_msi_cleanup(void);

+int fsl_mc_populate_irq_pool(struct fsl_mc_bus *mc_bus,
+ unsigned int irq_count);
+
+void fsl_mc_cleanup_irq_pool(struct fsl_mc_bus *mc_bus);
+
#endif /* _FSL_MC_PRIVATE_H_ */
diff --git a/drivers/staging/fsl-mc/include/mc.h b/drivers/staging/fsl-mc/include/mc.h
index 1c1d6ae..ac7c1ce 100644
--- a/drivers/staging/fsl-mc/include/mc.h
+++ b/drivers/staging/fsl-mc/include/mc.h
@@ -14,12 +14,14 @@
#include <linux/device.h>
#include <linux/mod_devicetable.h>
#include <linux/list.h>
+#include <linux/interrupt.h>
#include "../include/dprc.h"

#define FSL_MC_VENDOR_FREESCALE 0x1957

struct fsl_mc_device;
struct fsl_mc_io;
+struct fsl_mc_bus;

/**
* struct fsl_mc_driver - MC object device driver object
@@ -75,6 +77,7 @@ enum fsl_mc_pool_type {
FSL_MC_POOL_DPMCP = 0x0, /* corresponds to "dpmcp" in the MC */
FSL_MC_POOL_DPBP, /* corresponds to "dpbp" in the MC */
FSL_MC_POOL_DPCON, /* corresponds to "dpcon" in the MC */
+ FSL_MC_POOL_IRQ,

/*
* NOTE: New resource pool types must be added before this entry
@@ -141,6 +144,7 @@ struct fsl_mc_device_irq {
* NULL if none.
* @obj_desc: MC description of the DPAA device
* @regions: pointer to array of MMIO region entries
+ * @irqs: pointer to array of pointers to interrupts allocated to this device
* @resource: generic resource associated with this MC object device, if any.
*
* Generic device object for MC object devices that are "attached" to a
@@ -172,6 +176,7 @@ struct fsl_mc_device {
struct fsl_mc_io *mc_io;
struct dprc_obj_desc obj_desc;
struct resource *regions;
+ struct fsl_mc_device_irq **irqs;
struct fsl_mc_resource *resource;
};

@@ -215,6 +220,10 @@ int __must_check fsl_mc_object_allocate(struct fsl_mc_device *mc_dev,

void fsl_mc_object_free(struct fsl_mc_device *mc_adev);

+int __must_check fsl_mc_allocate_irqs(struct fsl_mc_device *mc_dev);
+
+void fsl_mc_free_irqs(struct fsl_mc_device *mc_dev);
+
extern struct bus_type fsl_mc_bus_type;

#endif /* _FSL_MC_H_ */
--
2.3.3

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