blob: b7f943f96068d116b2ee86217013f6cdc44e3655 [file] [log] [blame]
/*
* Freescale SCFG MSI(-X) support
*
* Copyright (C) 2016 Freescale Semiconductor.
*
* Author: Minghuan Lian <Minghuan.Lian@nxp.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/msi.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/irqdomain.h>
#include <linux/of_irq.h>
#include <linux/of_pci.h>
#include <linux/of_platform.h>
#include <linux/spinlock.h>
#include <linux/dma-iommu.h>
#define MSI_IRQS_PER_MSIR 32
#define MSI_MSIR_OFFSET 4
#define MSI_LS1043V1_1_IRQS_PER_MSIR 8
#define MSI_LS1043V1_1_MSIR_OFFSET 0x10
struct ls_scfg_msi_cfg {
u32 ibs_shift; /* Shift of interrupt bit select */
u32 msir_irqs; /* The irq number per MSIR */
u32 msir_base; /* The base address of MSIR */
};
struct ls_scfg_msir {
struct ls_scfg_msi *msi_data;
unsigned int index;
unsigned int gic_irq;
unsigned int bit_start;
unsigned int bit_end;
unsigned int srs; /* Shared interrupt register select */
void __iomem *reg;
};
struct ls_scfg_msi {
spinlock_t lock;
struct platform_device *pdev;
struct irq_domain *parent;
struct irq_domain *msi_domain;
void __iomem *regs;
phys_addr_t msiir_addr;
struct ls_scfg_msi_cfg *cfg;
u32 msir_num;
struct ls_scfg_msir *msir;
u32 irqs_num;
unsigned long *used;
};
static struct irq_chip ls_scfg_msi_irq_chip = {
.name = "MSI",
.irq_mask = pci_msi_mask_irq,
.irq_unmask = pci_msi_unmask_irq,
};
static struct msi_domain_info ls_scfg_msi_domain_info = {
.flags = (MSI_FLAG_USE_DEF_DOM_OPS |
MSI_FLAG_USE_DEF_CHIP_OPS |
MSI_FLAG_PCI_MSIX),
.chip = &ls_scfg_msi_irq_chip,
};
static int msi_affinity_flag = 1;
static int __init early_parse_ls_scfg_msi(char *p)
{
if (p && strncmp(p, "no-affinity", 11) == 0)
msi_affinity_flag = 0;
else
msi_affinity_flag = 1;
return 0;
}
early_param("lsmsi", early_parse_ls_scfg_msi);
static void ls_scfg_msi_compose_msg(struct irq_data *data, struct msi_msg *msg)
{
struct ls_scfg_msi *msi_data = irq_data_get_irq_chip_data(data);
msg->address_hi = upper_32_bits(msi_data->msiir_addr);
msg->address_lo = lower_32_bits(msi_data->msiir_addr);
msg->data = data->hwirq;
if (msi_affinity_flag)
msg->data |= cpumask_first(data->common->affinity);
iommu_dma_map_msi_msg(data->irq, msg);
}
static int ls_scfg_msi_set_affinity(struct irq_data *irq_data,
const struct cpumask *mask, bool force)
{
struct ls_scfg_msi *msi_data = irq_data_get_irq_chip_data(irq_data);
u32 cpu;
if (!msi_affinity_flag)
return -EINVAL;
if (!force)
cpu = cpumask_any_and(mask, cpu_online_mask);
else
cpu = cpumask_first(mask);
if (cpu >= msi_data->msir_num)
return -EINVAL;
if (msi_data->msir[cpu].gic_irq <= 0) {
pr_warn("cannot bind the irq to cpu%d\n", cpu);
return -EINVAL;
}
cpumask_copy(irq_data->common->affinity, mask);
return IRQ_SET_MASK_OK;
}
static struct irq_chip ls_scfg_msi_parent_chip = {
.name = "SCFG",
.irq_compose_msi_msg = ls_scfg_msi_compose_msg,
.irq_set_affinity = ls_scfg_msi_set_affinity,
};
static int ls_scfg_msi_domain_irq_alloc(struct irq_domain *domain,
unsigned int virq,
unsigned int nr_irqs,
void *args)
{
struct ls_scfg_msi *msi_data = domain->host_data;
int pos, err = 0;
WARN_ON(nr_irqs != 1);
spin_lock(&msi_data->lock);
pos = find_first_zero_bit(msi_data->used, msi_data->irqs_num);
if (pos < msi_data->irqs_num)
__set_bit(pos, msi_data->used);
else
err = -ENOSPC;
spin_unlock(&msi_data->lock);
if (err)
return err;
irq_domain_set_info(domain, virq, pos,
&ls_scfg_msi_parent_chip, msi_data,
handle_simple_irq, NULL, NULL);
return 0;
}
static void ls_scfg_msi_domain_irq_free(struct irq_domain *domain,
unsigned int virq, unsigned int nr_irqs)
{
struct irq_data *d = irq_domain_get_irq_data(domain, virq);
struct ls_scfg_msi *msi_data = irq_data_get_irq_chip_data(d);
int pos;
pos = d->hwirq;
if (pos < 0 || pos >= msi_data->irqs_num) {
pr_err("failed to teardown msi. Invalid hwirq %d\n", pos);
return;
}
spin_lock(&msi_data->lock);
__clear_bit(pos, msi_data->used);
spin_unlock(&msi_data->lock);
}
static const struct irq_domain_ops ls_scfg_msi_domain_ops = {
.alloc = ls_scfg_msi_domain_irq_alloc,
.free = ls_scfg_msi_domain_irq_free,
};
static void ls_scfg_msi_irq_handler(struct irq_desc *desc)
{
struct ls_scfg_msir *msir = irq_desc_get_handler_data(desc);
struct ls_scfg_msi *msi_data = msir->msi_data;
unsigned long val;
int pos, size, virq, hwirq;
chained_irq_enter(irq_desc_get_chip(desc), desc);
val = ioread32be(msir->reg);
pos = msir->bit_start;
size = msir->bit_end + 1;
for_each_set_bit_from(pos, &val, size) {
hwirq = ((msir->bit_end - pos) << msi_data->cfg->ibs_shift) |
msir->srs;
virq = irq_find_mapping(msi_data->parent, hwirq);
if (virq)
generic_handle_irq(virq);
}
chained_irq_exit(irq_desc_get_chip(desc), desc);
}
static int ls_scfg_msi_domains_init(struct ls_scfg_msi *msi_data)
{
/* Initialize MSI domain parent */
msi_data->parent = irq_domain_add_linear(NULL,
msi_data->irqs_num,
&ls_scfg_msi_domain_ops,
msi_data);
if (!msi_data->parent) {
dev_err(&msi_data->pdev->dev, "failed to create IRQ domain\n");
return -ENOMEM;
}
msi_data->msi_domain = pci_msi_create_irq_domain(
of_node_to_fwnode(msi_data->pdev->dev.of_node),
&ls_scfg_msi_domain_info,
msi_data->parent);
if (!msi_data->msi_domain) {
dev_err(&msi_data->pdev->dev, "failed to create MSI domain\n");
irq_domain_remove(msi_data->parent);
return -ENOMEM;
}
return 0;
}
static int ls_scfg_msi_setup_hwirq(struct ls_scfg_msi *msi_data, int index)
{
struct ls_scfg_msir *msir;
int virq, i, hwirq;
virq = platform_get_irq(msi_data->pdev, index);
if (virq <= 0)
return -ENODEV;
msir = &msi_data->msir[index];
msir->index = index;
msir->msi_data = msi_data;
msir->gic_irq = virq;
msir->reg = msi_data->regs + msi_data->cfg->msir_base + 4 * index;
if (msi_data->cfg->msir_irqs == MSI_LS1043V1_1_IRQS_PER_MSIR) {
msir->bit_start = 32 - ((msir->index + 1) *
MSI_LS1043V1_1_IRQS_PER_MSIR);
msir->bit_end = msir->bit_start +
MSI_LS1043V1_1_IRQS_PER_MSIR - 1;
} else {
msir->bit_start = 0;
msir->bit_end = msi_data->cfg->msir_irqs - 1;
}
irq_set_chained_handler_and_data(msir->gic_irq,
ls_scfg_msi_irq_handler,
msir);
if (msi_affinity_flag) {
/* Associate MSIR interrupt to the cpu */
irq_set_affinity(msir->gic_irq, get_cpu_mask(index));
msir->srs = 0; /* This value is determined by the CPU */
} else
msir->srs = index;
/* Release the hwirqs corresponding to this MSIR */
if (!msi_affinity_flag || msir->index == 0) {
for (i = 0; i < msi_data->cfg->msir_irqs; i++) {
hwirq = i << msi_data->cfg->ibs_shift | msir->index;
bitmap_clear(msi_data->used, hwirq, 1);
}
}
return 0;
}
static int ls_scfg_msi_teardown_hwirq(struct ls_scfg_msir *msir)
{
struct ls_scfg_msi *msi_data = msir->msi_data;
int i, hwirq;
if (msir->gic_irq > 0)
irq_set_chained_handler_and_data(msir->gic_irq, NULL, NULL);
for (i = 0; i < msi_data->cfg->msir_irqs; i++) {
hwirq = i << msi_data->cfg->ibs_shift | msir->index;
bitmap_set(msi_data->used, hwirq, 1);
}
return 0;
}
static struct ls_scfg_msi_cfg ls1021_msi_cfg = {
.ibs_shift = 3,
.msir_irqs = MSI_IRQS_PER_MSIR,
.msir_base = MSI_MSIR_OFFSET,
};
static struct ls_scfg_msi_cfg ls1046_msi_cfg = {
.ibs_shift = 2,
.msir_irqs = MSI_IRQS_PER_MSIR,
.msir_base = MSI_MSIR_OFFSET,
};
static struct ls_scfg_msi_cfg ls1043_v1_1_msi_cfg = {
.ibs_shift = 2,
.msir_irqs = MSI_LS1043V1_1_IRQS_PER_MSIR,
.msir_base = MSI_LS1043V1_1_MSIR_OFFSET,
};
static const struct of_device_id ls_scfg_msi_id[] = {
/* The following two misspelled compatibles are obsolete */
{ .compatible = "fsl,1s1021a-msi", .data = &ls1021_msi_cfg},
{ .compatible = "fsl,1s1043a-msi", .data = &ls1021_msi_cfg},
{ .compatible = "fsl,ls1021a-msi", .data = &ls1021_msi_cfg },
{ .compatible = "fsl,ls1043a-msi", .data = &ls1021_msi_cfg },
{ .compatible = "fsl,ls1043a-v1.1-msi", .data = &ls1043_v1_1_msi_cfg },
{ .compatible = "fsl,ls1046a-msi", .data = &ls1046_msi_cfg },
{},
};
MODULE_DEVICE_TABLE(of, ls_scfg_msi_id);
static int ls_scfg_msi_probe(struct platform_device *pdev)
{
const struct of_device_id *match;
struct ls_scfg_msi *msi_data;
struct resource *res;
int i, ret;
match = of_match_device(ls_scfg_msi_id, &pdev->dev);
if (!match)
return -ENODEV;
msi_data = devm_kzalloc(&pdev->dev, sizeof(*msi_data), GFP_KERNEL);
if (!msi_data)
return -ENOMEM;
msi_data->cfg = (struct ls_scfg_msi_cfg *) match->data;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
msi_data->regs = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(msi_data->regs)) {
dev_err(&pdev->dev, "failed to initialize 'regs'\n");
return PTR_ERR(msi_data->regs);
}
msi_data->msiir_addr = res->start;
msi_data->pdev = pdev;
spin_lock_init(&msi_data->lock);
msi_data->irqs_num = MSI_IRQS_PER_MSIR *
(1 << msi_data->cfg->ibs_shift);
msi_data->used = devm_kcalloc(&pdev->dev,
BITS_TO_LONGS(msi_data->irqs_num),
sizeof(*msi_data->used),
GFP_KERNEL);
if (!msi_data->used)
return -ENOMEM;
/*
* Reserve all the hwirqs
* The available hwirqs will be released in ls1_msi_setup_hwirq()
*/
bitmap_set(msi_data->used, 0, msi_data->irqs_num);
msi_data->msir_num = of_irq_count(pdev->dev.of_node);
if (msi_affinity_flag) {
u32 cpu_num;
cpu_num = num_possible_cpus();
if (msi_data->msir_num >= cpu_num)
msi_data->msir_num = cpu_num;
else
msi_affinity_flag = 0;
}
msi_data->msir = devm_kcalloc(&pdev->dev, msi_data->msir_num,
sizeof(*msi_data->msir),
GFP_KERNEL);
if (!msi_data->msir)
return -ENOMEM;
for (i = 0; i < msi_data->msir_num; i++)
ls_scfg_msi_setup_hwirq(msi_data, i);
ret = ls_scfg_msi_domains_init(msi_data);
if (ret)
return ret;
platform_set_drvdata(pdev, msi_data);
return 0;
}
static int ls_scfg_msi_remove(struct platform_device *pdev)
{
struct ls_scfg_msi *msi_data = platform_get_drvdata(pdev);
int i;
for (i = 0; i < msi_data->msir_num; i++)
ls_scfg_msi_teardown_hwirq(&msi_data->msir[i]);
irq_domain_remove(msi_data->msi_domain);
irq_domain_remove(msi_data->parent);
platform_set_drvdata(pdev, NULL);
return 0;
}
static struct platform_driver ls_scfg_msi_driver = {
.driver = {
.name = "ls-scfg-msi",
.of_match_table = ls_scfg_msi_id,
},
.probe = ls_scfg_msi_probe,
.remove = ls_scfg_msi_remove,
};
module_platform_driver(ls_scfg_msi_driver);
MODULE_AUTHOR("Minghuan Lian <Minghuan.Lian@nxp.com>");
MODULE_DESCRIPTION("Freescale Layerscape SCFG MSI controller driver");
MODULE_LICENSE("GPL v2");