diff options
Diffstat (limited to 'drivers/misc/cxl/main.c')
| -rw-r--r-- | drivers/misc/cxl/main.c | 230 |
1 files changed, 230 insertions, 0 deletions
diff --git a/drivers/misc/cxl/main.c b/drivers/misc/cxl/main.c new file mode 100644 index 000000000000..4cde9b661642 --- /dev/null +++ b/drivers/misc/cxl/main.c @@ -0,0 +1,230 @@ +/* + * Copyright 2014 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. + */ + +#include <linux/spinlock.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/device.h> +#include <linux/mutex.h> +#include <linux/init.h> +#include <linux/list.h> +#include <linux/mm.h> +#include <linux/of.h> +#include <linux/slab.h> +#include <linux/idr.h> +#include <linux/pci.h> +#include <asm/cputable.h> +#include <misc/cxl.h> + +#include "cxl.h" + +static DEFINE_SPINLOCK(adapter_idr_lock); +static DEFINE_IDR(cxl_adapter_idr); + +uint cxl_verbose; +module_param_named(verbose, cxl_verbose, uint, 0600); +MODULE_PARM_DESC(verbose, "Enable verbose dmesg output"); + +static inline void _cxl_slbia(struct cxl_context *ctx, struct mm_struct *mm) +{ + struct task_struct *task; + unsigned long flags; + if (!(task = get_pid_task(ctx->pid, PIDTYPE_PID))) { + pr_devel("%s unable to get task %i\n", + __func__, pid_nr(ctx->pid)); + return; + } + + if (task->mm != mm) + goto out_put; + + pr_devel("%s matched mm - card: %i afu: %i pe: %i\n", __func__, + ctx->afu->adapter->adapter_num, ctx->afu->slice, ctx->pe); + + spin_lock_irqsave(&ctx->sste_lock, flags); + memset(ctx->sstp, 0, ctx->sst_size); + spin_unlock_irqrestore(&ctx->sste_lock, flags); + mb(); + cxl_afu_slbia(ctx->afu); +out_put: + put_task_struct(task); +} + +static inline void cxl_slbia_core(struct mm_struct *mm) +{ + struct cxl *adapter; + struct cxl_afu *afu; + struct cxl_context *ctx; + int card, slice, id; + + pr_devel("%s called\n", __func__); + + spin_lock(&adapter_idr_lock); + idr_for_each_entry(&cxl_adapter_idr, adapter, card) { + /* XXX: Make this lookup faster with link from mm to ctx */ + spin_lock(&adapter->afu_list_lock); + for (slice = 0; slice < adapter->slices; slice++) { + afu = adapter->afu[slice]; + if (!afu->enabled) + continue; + rcu_read_lock(); + idr_for_each_entry(&afu->contexts_idr, ctx, id) + _cxl_slbia(ctx, mm); + rcu_read_unlock(); + } + spin_unlock(&adapter->afu_list_lock); + } + spin_unlock(&adapter_idr_lock); +} + +static struct cxl_calls cxl_calls = { + .cxl_slbia = cxl_slbia_core, + .owner = THIS_MODULE, +}; + +int cxl_alloc_sst(struct cxl_context *ctx) +{ + unsigned long vsid; + u64 ea_mask, size, sstp0, sstp1; + + sstp0 = 0; + sstp1 = 0; + + ctx->sst_size = PAGE_SIZE; + ctx->sst_lru = 0; + ctx->sstp = (struct cxl_sste *)get_zeroed_page(GFP_KERNEL); + if (!ctx->sstp) { + pr_err("cxl_alloc_sst: Unable to allocate segment table\n"); + return -ENOMEM; + } + pr_devel("SSTP allocated at 0x%p\n", ctx->sstp); + + vsid = get_kernel_vsid((u64)ctx->sstp, mmu_kernel_ssize) << 12; + + sstp0 |= (u64)mmu_kernel_ssize << CXL_SSTP0_An_B_SHIFT; + sstp0 |= (SLB_VSID_KERNEL | mmu_psize_defs[mmu_linear_psize].sllp) << 50; + + size = (((u64)ctx->sst_size >> 8) - 1) << CXL_SSTP0_An_SegTableSize_SHIFT; + if (unlikely(size & ~CXL_SSTP0_An_SegTableSize_MASK)) { + WARN(1, "Impossible segment table size\n"); + return -EINVAL; + } + sstp0 |= size; + + if (mmu_kernel_ssize == MMU_SEGSIZE_256M) + ea_mask = 0xfffff00ULL; + else + ea_mask = 0xffffffff00ULL; + + sstp0 |= vsid >> (50-14); /* Top 14 bits of VSID */ + sstp1 |= (vsid << (64-(50-14))) & ~ea_mask; + sstp1 |= (u64)ctx->sstp & ea_mask; + sstp1 |= CXL_SSTP1_An_V; + + pr_devel("Looked up %#llx: slbfee. %#llx (ssize: %x, vsid: %#lx), copied to SSTP0: %#llx, SSTP1: %#llx\n", + (u64)ctx->sstp, (u64)ctx->sstp & ESID_MASK, mmu_kernel_ssize, vsid, sstp0, sstp1); + + /* Store calculated sstp hardware points for use later */ + ctx->sstp0 = sstp0; + ctx->sstp1 = sstp1; + + return 0; +} + +/* Find a CXL adapter by it's number and increase it's refcount */ +struct cxl *get_cxl_adapter(int num) +{ + struct cxl *adapter; + + spin_lock(&adapter_idr_lock); + if ((adapter = idr_find(&cxl_adapter_idr, num))) + get_device(&adapter->dev); + spin_unlock(&adapter_idr_lock); + + return adapter; +} + +int cxl_alloc_adapter_nr(struct cxl *adapter) +{ + int i; + + idr_preload(GFP_KERNEL); + spin_lock(&adapter_idr_lock); + i = idr_alloc(&cxl_adapter_idr, adapter, 0, 0, GFP_NOWAIT); + spin_unlock(&adapter_idr_lock); + idr_preload_end(); + if (i < 0) + return i; + + adapter->adapter_num = i; + + return 0; +} + +void cxl_remove_adapter_nr(struct cxl *adapter) +{ + idr_remove(&cxl_adapter_idr, adapter->adapter_num); +} + +int cxl_afu_select_best_mode(struct cxl_afu *afu) +{ + if (afu->modes_supported & CXL_MODE_DIRECTED) + return cxl_afu_activate_mode(afu, CXL_MODE_DIRECTED); + + if (afu->modes_supported & CXL_MODE_DEDICATED) + return cxl_afu_activate_mode(afu, CXL_MODE_DEDICATED); + + dev_warn(&afu->dev, "No supported programming modes available\n"); + /* We don't fail this so the user can inspect sysfs */ + return 0; +} + +static int __init init_cxl(void) +{ + int rc = 0; + + if (!cpu_has_feature(CPU_FTR_HVMODE)) + return -EPERM; + + if ((rc = cxl_file_init())) + return rc; + + cxl_debugfs_init(); + + if ((rc = register_cxl_calls(&cxl_calls))) + goto err; + + if ((rc = pci_register_driver(&cxl_pci_driver))) + goto err1; + + return 0; +err1: + unregister_cxl_calls(&cxl_calls); +err: + cxl_debugfs_exit(); + cxl_file_exit(); + + return rc; +} + +static void exit_cxl(void) +{ + pci_unregister_driver(&cxl_pci_driver); + + cxl_debugfs_exit(); + cxl_file_exit(); + unregister_cxl_calls(&cxl_calls); +} + +module_init(init_cxl); +module_exit(exit_cxl); + +MODULE_DESCRIPTION("IBM Coherent Accelerator"); +MODULE_AUTHOR("Ian Munsie <imunsie@au1.ibm.com>"); +MODULE_LICENSE("GPL"); |