diff options
Diffstat (limited to 'drivers/irqchip/irq-mvebu-odmi.c')
-rw-r--r-- | drivers/irqchip/irq-mvebu-odmi.c | 236 |
1 files changed, 236 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-mvebu-odmi.c b/drivers/irqchip/irq-mvebu-odmi.c new file mode 100644 index 000000000..b4d367868 --- /dev/null +++ b/drivers/irqchip/irq-mvebu-odmi.c @@ -0,0 +1,236 @@ +/* + * Copyright (C) 2016 Marvell + * + * Thomas Petazzoni <thomas.petazzoni@free-electrons.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. + */ + +#define pr_fmt(fmt) "GIC-ODMI: " fmt + +#include <linux/irq.h> +#include <linux/irqchip.h> +#include <linux/irqdomain.h> +#include <linux/kernel.h> +#include <linux/msi.h> +#include <linux/of_address.h> +#include <linux/slab.h> +#include <dt-bindings/interrupt-controller/arm-gic.h> + +#define GICP_ODMIN_SET 0x40 +#define GICP_ODMI_INT_NUM_SHIFT 12 +#define GICP_ODMIN_GM_EP_R0 0x110 +#define GICP_ODMIN_GM_EP_R1 0x114 +#define GICP_ODMIN_GM_EA_R0 0x108 +#define GICP_ODMIN_GM_EA_R1 0x118 + +/* + * We don't support the group events, so we simply have 8 interrupts + * per frame. + */ +#define NODMIS_SHIFT 3 +#define NODMIS_PER_FRAME (1 << NODMIS_SHIFT) +#define NODMIS_MASK (NODMIS_PER_FRAME - 1) + +struct odmi_data { + struct resource res; + void __iomem *base; + unsigned int spi_base; +}; + +static struct odmi_data *odmis; +static unsigned long *odmis_bm; +static unsigned int odmis_count; + +/* Protects odmis_bm */ +static DEFINE_SPINLOCK(odmis_bm_lock); + +static void odmi_compose_msi_msg(struct irq_data *d, struct msi_msg *msg) +{ + struct odmi_data *odmi; + phys_addr_t addr; + unsigned int odmin; + + if (WARN_ON(d->hwirq >= odmis_count * NODMIS_PER_FRAME)) + return; + + odmi = &odmis[d->hwirq >> NODMIS_SHIFT]; + odmin = d->hwirq & NODMIS_MASK; + + addr = odmi->res.start + GICP_ODMIN_SET; + + msg->address_hi = upper_32_bits(addr); + msg->address_lo = lower_32_bits(addr); + msg->data = odmin << GICP_ODMI_INT_NUM_SHIFT; +} + +static struct irq_chip odmi_irq_chip = { + .name = "ODMI", + .irq_mask = irq_chip_mask_parent, + .irq_unmask = irq_chip_unmask_parent, + .irq_eoi = irq_chip_eoi_parent, + .irq_set_affinity = irq_chip_set_affinity_parent, + .irq_compose_msi_msg = odmi_compose_msi_msg, +}; + +static int odmi_irq_domain_alloc(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs, void *args) +{ + struct odmi_data *odmi = NULL; + struct irq_fwspec fwspec; + struct irq_data *d; + unsigned int hwirq, odmin; + int ret; + + spin_lock(&odmis_bm_lock); + hwirq = find_first_zero_bit(odmis_bm, NODMIS_PER_FRAME * odmis_count); + if (hwirq >= NODMIS_PER_FRAME * odmis_count) { + spin_unlock(&odmis_bm_lock); + return -ENOSPC; + } + + __set_bit(hwirq, odmis_bm); + spin_unlock(&odmis_bm_lock); + + odmi = &odmis[hwirq >> NODMIS_SHIFT]; + odmin = hwirq & NODMIS_MASK; + + fwspec.fwnode = domain->parent->fwnode; + fwspec.param_count = 3; + fwspec.param[0] = GIC_SPI; + fwspec.param[1] = odmi->spi_base - 32 + odmin; + fwspec.param[2] = IRQ_TYPE_EDGE_RISING; + + ret = irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec); + if (ret) { + pr_err("Cannot allocate parent IRQ\n"); + spin_lock(&odmis_bm_lock); + __clear_bit(odmin, odmis_bm); + spin_unlock(&odmis_bm_lock); + return ret; + } + + /* Configure the interrupt line to be edge */ + d = irq_domain_get_irq_data(domain->parent, virq); + d->chip->irq_set_type(d, IRQ_TYPE_EDGE_RISING); + + irq_domain_set_hwirq_and_chip(domain, virq, hwirq, + &odmi_irq_chip, NULL); + + return 0; +} + +static void odmi_irq_domain_free(struct irq_domain *domain, + unsigned int virq, unsigned int nr_irqs) +{ + struct irq_data *d = irq_domain_get_irq_data(domain, virq); + + if (d->hwirq >= odmis_count * NODMIS_PER_FRAME) { + pr_err("Failed to teardown msi. Invalid hwirq %lu\n", d->hwirq); + return; + } + + irq_domain_free_irqs_parent(domain, virq, nr_irqs); + + /* Actually free the MSI */ + spin_lock(&odmis_bm_lock); + __clear_bit(d->hwirq, odmis_bm); + spin_unlock(&odmis_bm_lock); +} + +static const struct irq_domain_ops odmi_domain_ops = { + .alloc = odmi_irq_domain_alloc, + .free = odmi_irq_domain_free, +}; + +static struct irq_chip odmi_msi_irq_chip = { + .name = "ODMI", +}; + +static struct msi_domain_ops odmi_msi_ops = { +}; + +static struct msi_domain_info odmi_msi_domain_info = { + .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS), + .ops = &odmi_msi_ops, + .chip = &odmi_msi_irq_chip, +}; + +static int __init mvebu_odmi_init(struct device_node *node, + struct device_node *parent) +{ + struct irq_domain *inner_domain, *plat_domain; + int ret, i; + + if (of_property_read_u32(node, "marvell,odmi-frames", &odmis_count)) + return -EINVAL; + + odmis = kcalloc(odmis_count, sizeof(struct odmi_data), GFP_KERNEL); + if (!odmis) + return -ENOMEM; + + odmis_bm = kcalloc(BITS_TO_LONGS(odmis_count * NODMIS_PER_FRAME), + sizeof(long), GFP_KERNEL); + if (!odmis_bm) { + ret = -ENOMEM; + goto err_alloc; + } + + for (i = 0; i < odmis_count; i++) { + struct odmi_data *odmi = &odmis[i]; + + ret = of_address_to_resource(node, i, &odmi->res); + if (ret) + goto err_unmap; + + odmi->base = of_io_request_and_map(node, i, "odmi"); + if (IS_ERR(odmi->base)) { + ret = PTR_ERR(odmi->base); + goto err_unmap; + } + + if (of_property_read_u32_index(node, "marvell,spi-base", + i, &odmi->spi_base)) { + ret = -EINVAL; + goto err_unmap; + } + } + + inner_domain = irq_domain_create_linear(of_node_to_fwnode(node), + odmis_count * NODMIS_PER_FRAME, + &odmi_domain_ops, NULL); + if (!inner_domain) { + ret = -ENOMEM; + goto err_unmap; + } + + inner_domain->parent = irq_find_host(parent); + + plat_domain = platform_msi_create_irq_domain(of_node_to_fwnode(node), + &odmi_msi_domain_info, + inner_domain); + if (!plat_domain) { + ret = -ENOMEM; + goto err_remove_inner; + } + + return 0; + +err_remove_inner: + irq_domain_remove(inner_domain); +err_unmap: + for (i = 0; i < odmis_count; i++) { + struct odmi_data *odmi = &odmis[i]; + + if (odmi->base && !IS_ERR(odmi->base)) + iounmap(odmis[i].base); + } + kfree(odmis_bm); +err_alloc: + kfree(odmis); + return ret; +} + +IRQCHIP_DECLARE(mvebu_odmi, "marvell,odmi-controller", mvebu_odmi_init); |