diff options
Diffstat (limited to 'arch/powerpc/platforms/powernv/vas.c')
| -rw-r--r-- | arch/powerpc/platforms/powernv/vas.c | 179 |
1 files changed, 179 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..5a2b24cbb --- /dev/null +++ b/arch/powerpc/platforms/powernv/vas.c @@ -0,0 +1,179 @@ +/* + * Copyright 2016-17 IBM Corp. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#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 <asm/prom.h> + +#include "vas.h" + +DEFINE_MUTEX(vas_mutex); +static LIST_HEAD(vas_instances); + +static DEFINE_PER_CPU(int, cpu_vas_id); + +static int init_vas_instance(struct platform_device *pdev) +{ + int rc, cpu, vasid; + struct resource *res; + struct vas_instance *vinst; + struct device_node *dn = pdev->dev.of_node; + + 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; + } + + 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; + + pr_devel("Initialized instance [%s, %d], paste_base 0x%llx, " + "paste_win_id_shift 0x%llx\n", pdev->name, vasid, + vinst->paste_base_addr, vinst->paste_win_id_shift); + + 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); + + 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); |