diff options
Diffstat (limited to 'arch/powerpc/platforms/powernv/vas.c')
| -rw-r--r-- | arch/powerpc/platforms/powernv/vas.c | 248 |
1 files changed, 248 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/powernv/vas.c b/arch/powerpc/platforms/powernv/vas.c new file mode 100644 index 000000000..598e4cd56 --- /dev/null +++ b/arch/powerpc/platforms/powernv/vas.c @@ -0,0 +1,248 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright 2016-17 IBM Corp. + */ + +#define pr_fmt(fmt) "vas: " fmt + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/export.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/platform_device.h> +#include <linux/of_platform.h> +#include <linux/of_address.h> +#include <linux/of.h> +#include <linux/irqdomain.h> +#include <linux/interrupt.h> +#include <asm/prom.h> +#include <asm/xive.h> + +#include "vas.h" + +DEFINE_MUTEX(vas_mutex); +static LIST_HEAD(vas_instances); + +static DEFINE_PER_CPU(int, cpu_vas_id); + +static int vas_irq_fault_window_setup(struct vas_instance *vinst) +{ + char devname[64]; + int rc = 0; + + snprintf(devname, sizeof(devname), "vas-%d", vinst->vas_id); + rc = request_threaded_irq(vinst->virq, vas_fault_handler, + vas_fault_thread_fn, 0, devname, vinst); + + if (rc) { + pr_err("VAS[%d]: Request IRQ(%d) failed with %d\n", + vinst->vas_id, vinst->virq, rc); + goto out; + } + + rc = vas_setup_fault_window(vinst); + if (rc) + free_irq(vinst->virq, vinst); + +out: + return rc; +} + +static int init_vas_instance(struct platform_device *pdev) +{ + struct device_node *dn = pdev->dev.of_node; + struct vas_instance *vinst; + struct xive_irq_data *xd; + uint32_t chipid, hwirq; + struct resource *res; + int rc, cpu, vasid; + + rc = of_property_read_u32(dn, "ibm,vas-id", &vasid); + if (rc) { + pr_err("No ibm,vas-id property for %s?\n", pdev->name); + return -ENODEV; + } + + rc = of_property_read_u32(dn, "ibm,chip-id", &chipid); + if (rc) { + pr_err("No ibm,chip-id property for %s?\n", pdev->name); + return -ENODEV; + } + + if (pdev->num_resources != 4) { + pr_err("Unexpected DT configuration for [%s, %d]\n", + pdev->name, vasid); + return -ENODEV; + } + + vinst = kzalloc(sizeof(*vinst), GFP_KERNEL); + if (!vinst) + return -ENOMEM; + + INIT_LIST_HEAD(&vinst->node); + ida_init(&vinst->ida); + mutex_init(&vinst->mutex); + vinst->vas_id = vasid; + vinst->pdev = pdev; + + res = &pdev->resource[0]; + vinst->hvwc_bar_start = res->start; + + res = &pdev->resource[1]; + vinst->uwc_bar_start = res->start; + + res = &pdev->resource[2]; + vinst->paste_base_addr = res->start; + + res = &pdev->resource[3]; + if (res->end > 62) { + pr_err("Bad 'paste_win_id_shift' in DT, %llx\n", res->end); + goto free_vinst; + } + + vinst->paste_win_id_shift = 63 - res->end; + + hwirq = xive_native_alloc_irq_on_chip(chipid); + if (!hwirq) { + pr_err("Inst%d: Unable to allocate global irq for chip %d\n", + vinst->vas_id, chipid); + return -ENOENT; + } + + vinst->virq = irq_create_mapping(NULL, hwirq); + if (!vinst->virq) { + pr_err("Inst%d: Unable to map global irq %d\n", + vinst->vas_id, hwirq); + return -EINVAL; + } + + xd = irq_get_handler_data(vinst->virq); + if (!xd) { + pr_err("Inst%d: Invalid virq %d\n", + vinst->vas_id, vinst->virq); + return -EINVAL; + } + + vinst->irq_port = xd->trig_page; + pr_devel("Initialized instance [%s, %d] paste_base 0x%llx paste_win_id_shift 0x%llx IRQ %d Port 0x%llx\n", + pdev->name, vasid, vinst->paste_base_addr, + vinst->paste_win_id_shift, vinst->virq, + vinst->irq_port); + + for_each_possible_cpu(cpu) { + if (cpu_to_chip_id(cpu) == of_get_ibm_chip_id(dn)) + per_cpu(cpu_vas_id, cpu) = vasid; + } + + mutex_lock(&vas_mutex); + list_add(&vinst->node, &vas_instances); + mutex_unlock(&vas_mutex); + + spin_lock_init(&vinst->fault_lock); + /* + * IRQ and fault handling setup is needed only for user space + * send windows. + */ + if (vinst->virq) { + rc = vas_irq_fault_window_setup(vinst); + /* + * Fault window is used only for user space send windows. + * So if vinst->virq is NULL, tx_win_open returns -ENODEV + * for user space. + */ + if (rc) + vinst->virq = 0; + } + + vas_instance_init_dbgdir(vinst); + + dev_set_drvdata(&pdev->dev, vinst); + + return 0; + +free_vinst: + kfree(vinst); + return -ENODEV; + +} + +/* + * Although this is read/used multiple times, it is written to only + * during initialization. + */ +struct vas_instance *find_vas_instance(int vasid) +{ + struct list_head *ent; + struct vas_instance *vinst; + + mutex_lock(&vas_mutex); + + if (vasid == -1) + vasid = per_cpu(cpu_vas_id, smp_processor_id()); + + list_for_each(ent, &vas_instances) { + vinst = list_entry(ent, struct vas_instance, node); + if (vinst->vas_id == vasid) { + mutex_unlock(&vas_mutex); + return vinst; + } + } + mutex_unlock(&vas_mutex); + + pr_devel("Instance %d not found\n", vasid); + return NULL; +} + +int chip_to_vas_id(int chipid) +{ + int cpu; + + for_each_possible_cpu(cpu) { + if (cpu_to_chip_id(cpu) == chipid) + return per_cpu(cpu_vas_id, cpu); + } + return -1; +} +EXPORT_SYMBOL(chip_to_vas_id); + +static int vas_probe(struct platform_device *pdev) +{ + return init_vas_instance(pdev); +} + +static const struct of_device_id powernv_vas_match[] = { + { .compatible = "ibm,vas",}, + {}, +}; + +static struct platform_driver vas_driver = { + .driver = { + .name = "vas", + .of_match_table = powernv_vas_match, + }, + .probe = vas_probe, +}; + +static int __init vas_init(void) +{ + int found = 0; + struct device_node *dn; + + platform_driver_register(&vas_driver); + + for_each_compatible_node(dn, NULL, "ibm,vas") { + of_platform_device_create(dn, NULL, NULL); + found++; + } + + if (!found) { + platform_driver_unregister(&vas_driver); + return -ENODEV; + } + + pr_devel("Found %d instances\n", found); + + return 0; +} +device_initcall(vas_init); |