[mirror_ubuntu-artful-kernel.git] / drivers / misc / cxl / main.c

/*
 * 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 <linux/sched/task.h>

#include <asm/cputable.h>
#include <misc/cxl-base.h>

#include "cxl.h"
#include "trace.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");

const struct cxl_backend_ops *cxl_ops;

int cxl_afu_slbia(struct cxl_afu *afu)
{
	unsigned long timeout = jiffies + (HZ * CXL_TIMEOUT);

	pr_devel("cxl_afu_slbia issuing SLBIA command\n");
	cxl_p2n_write(afu, CXL_SLBIA_An, CXL_TLB_SLB_IQ_ALL);
	while (cxl_p2n_read(afu, CXL_SLBIA_An) & CXL_TLB_SLB_P) {
		if (time_after_eq(jiffies, timeout)) {
			dev_warn(&afu->dev, "WARNING: CXL AFU SLBIA timed out!\n");
			return -EBUSY;
		}
		/* If the adapter has gone down, we can assume that we
		 * will PERST it and that will invalidate everything.
		 */
		if (!cxl_ops->link_ok(afu->adapter, afu))
			return -EIO;
		cpu_relax();
	}
	return 0;
}

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);
	trace_cxl_slbia(ctx);
	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 || !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,
	.cxl_pci_associate_default_context = _cxl_pci_associate_default_context,
	.cxl_pci_disable_device = _cxl_pci_disable_device,
	.cxl_next_msi_hwirq = _cxl_next_msi_hwirq,
	.cxl_cx4_setup_msi_irqs = _cxl_cx4_setup_msi_irqs,
	.cxl_cx4_teardown_msi_irqs = _cxl_cx4_teardown_msi_irqs,
	.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;
}

/* print buffer content as integers when debugging */
void cxl_dump_debug_buffer(void *buf, size_t buf_len)
{
#ifdef DEBUG
	int i, *ptr;

	/*
	 * We want to regroup up to 4 integers per line, which means they
	 * need to be in the same pr_devel() statement
	 */
	ptr = (int *) buf;
	for (i = 0; i * 4 < buf_len; i += 4) {
		if ((i + 3) * 4 < buf_len)
			pr_devel("%.8x %.8x %.8x %.8x\n", ptr[i], ptr[i + 1],
				ptr[i + 2], ptr[i + 3]);
		else if ((i + 2) * 4 < buf_len)
			pr_devel("%.8x %.8x %.8x\n", ptr[i], ptr[i + 1],
				ptr[i + 2]);
		else if ((i + 1) * 4 < buf_len)
			pr_devel("%.8x %.8x\n", ptr[i], ptr[i + 1]);
		else
			pr_devel("%.8x\n", ptr[i]);
	}
#endif /* DEBUG */
}

/* 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;
}

static 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);
}

struct cxl *cxl_alloc_adapter(void)
{
	struct cxl *adapter;

	if (!(adapter = kzalloc(sizeof(struct cxl), GFP_KERNEL)))
		return NULL;

	spin_lock_init(&adapter->afu_list_lock);

	if (cxl_alloc_adapter_nr(adapter))
		goto err1;

	if (dev_set_name(&adapter->dev, "card%i", adapter->adapter_num))
		goto err2;

	/* start with context lock taken */
	atomic_set(&adapter->contexts_num, -1);

	return adapter;
err2:
	cxl_remove_adapter_nr(adapter);
err1:
	kfree(adapter);
	return NULL;
}

struct cxl_afu *cxl_alloc_afu(struct cxl *adapter, int slice)
{
	struct cxl_afu *afu;

	if (!(afu = kzalloc(sizeof(struct cxl_afu), GFP_KERNEL)))
		return NULL;

	afu->adapter = adapter;
	afu->dev.parent = &adapter->dev;
	afu->dev.release = cxl_ops->release_afu;
	afu->slice = slice;
	idr_init(&afu->contexts_idr);
	mutex_init(&afu->contexts_lock);
	spin_lock_init(&afu->afu_cntl_lock);
	atomic_set(&afu->configured_state, -1);
	afu->prefault_mode = CXL_PREFAULT_NONE;
	afu->irqs_max = afu->adapter->user_irqs;

	return afu;
}

int cxl_afu_select_best_mode(struct cxl_afu *afu)
{
	if (afu->modes_supported & CXL_MODE_DIRECTED)
		return cxl_ops->afu_activate_mode(afu, CXL_MODE_DIRECTED);

	if (afu->modes_supported & CXL_MODE_DEDICATED)
		return cxl_ops->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;
}

int cxl_adapter_context_get(struct cxl *adapter)
{
	int rc;

	rc = atomic_inc_unless_negative(&adapter->contexts_num);
	return rc >= 0 ? 0 : -EBUSY;
}

void cxl_adapter_context_put(struct cxl *adapter)
{
	atomic_dec_if_positive(&adapter->contexts_num);
}

int cxl_adapter_context_lock(struct cxl *adapter)
{
	int rc;
	/* no active contexts -> contexts_num == 0 */
	rc = atomic_cmpxchg(&adapter->contexts_num, 0, -1);
	return rc ? -EBUSY : 0;
}

void cxl_adapter_context_unlock(struct cxl *adapter)
{
	int val = atomic_cmpxchg(&adapter->contexts_num, -1, 0);

	/*
	 * contexts lock taken -> contexts_num == -1
	 * If not true then show a warning and force reset the lock.
	 * This will happen when context_unlock was requested without
	 * doing a context_lock.
	 */
	if (val != -1) {
		atomic_set(&adapter->contexts_num, 0);
		WARN(1, "Adapter context unlocked with %d active contexts",
		     val);
	}
}

static int __init init_cxl(void)
{
	int rc = 0;

	if ((rc = cxl_file_init()))
		return rc;

	cxl_debugfs_init();

	if ((rc = register_cxl_calls(&cxl_calls)))
		goto err;

	if (cpu_has_feature(CPU_FTR_HVMODE)) {
		cxl_ops = &cxl_native_ops;
		rc = pci_register_driver(&cxl_pci_driver);
	}
#ifdef CONFIG_PPC_PSERIES
	else {
		cxl_ops = &cxl_guest_ops;
		rc = platform_driver_register(&cxl_of_driver);
	}
#endif
	if (rc)
		goto err1;

	return 0;
err1:
	unregister_cxl_calls(&cxl_calls);
err:
	cxl_debugfs_exit();
	cxl_file_exit();

	return rc;
}

static void exit_cxl(void)
{
	if (cpu_has_feature(CPU_FTR_HVMODE))
		pci_unregister_driver(&cxl_pci_driver);
#ifdef CONFIG_PPC_PSERIES
	else
		platform_driver_unregister(&cxl_of_driver);
#endif

	cxl_debugfs_exit();
	cxl_file_exit();
	unregister_cxl_calls(&cxl_calls);
	idr_destroy(&cxl_adapter_idr);
}

module_init(init_cxl);
module_exit(exit_cxl);

MODULE_DESCRIPTION("IBM Coherent Accelerator");
MODULE_AUTHOR("Ian Munsie <imunsie@au1.ibm.com>");
MODULE_LICENSE("GPL");
Commit	Line	Data
f204e0b8 IM	1	/*
	2	* Copyright 2014 IBM Corp.
	3	*
	4	* This program is free software; you can redistribute it and/or
	5	* modify it under the terms of the GNU General Public License
	6	* as published by the Free Software Foundation; either version
	7	* 2 of the License, or (at your option) any later version.
	8	*/
	9
	10	#include <linux/spinlock.h>
	11	#include <linux/kernel.h>
	12	#include <linux/module.h>
	13	#include <linux/device.h>
	14	#include <linux/mutex.h>
	15	#include <linux/init.h>
	16	#include <linux/list.h>
	17	#include <linux/mm.h>
	18	#include <linux/of.h>
	19	#include <linux/slab.h>
	20	#include <linux/idr.h>
	21	#include <linux/pci.h>
0881e7bd IM	22	#include <linux/sched/task.h>
0881e7bd IM	23
f204e0b8	24	#include <asm/cputable.h>
ec249dd8	25	#include <misc/cxl-base.h>
f204e0b8 IM	26
f204e0b8 IM	27	#include "cxl.h"
9bcf28cd	28	#include "trace.h"
f204e0b8 IM	29
	30	static DEFINE_SPINLOCK(adapter_idr_lock);
	31	static DEFINE_IDR(cxl_adapter_idr);
	32
	33	uint cxl_verbose;
	34	module_param_named(verbose, cxl_verbose, uint, 0600);
	35	MODULE_PARM_DESC(verbose, "Enable verbose dmesg output");
	36
5be587b1 FB	37	const struct cxl_backend_ops *cxl_ops;
5be587b1 FB	38
86331862 CL	39	int cxl_afu_slbia(struct cxl_afu *afu)
	40	{
	41	unsigned long timeout = jiffies + (HZ * CXL_TIMEOUT);
	42
	43	pr_devel("cxl_afu_slbia issuing SLBIA command\n");
	44	cxl_p2n_write(afu, CXL_SLBIA_An, CXL_TLB_SLB_IQ_ALL);
	45	while (cxl_p2n_read(afu, CXL_SLBIA_An) & CXL_TLB_SLB_P) {
	46	if (time_after_eq(jiffies, timeout)) {
	47	dev_warn(&afu->dev, "WARNING: CXL AFU SLBIA timed out!\n");
	48	return -EBUSY;
	49	}
	50	/* If the adapter has gone down, we can assume that we
	51	* will PERST it and that will invalidate everything.
	52	*/
0d400f77	53	if (!cxl_ops->link_ok(afu->adapter, afu))
86331862 CL	54	return -EIO;
	55	cpu_relax();
	56	}
	57	return 0;
	58	}
	59
f204e0b8 IM	60	static inline void _cxl_slbia(struct cxl_context ctx, struct mm_struct mm)
	61	{
	62	struct task_struct *task;
	63	unsigned long flags;
	64	if (!(task = get_pid_task(ctx->pid, PIDTYPE_PID))) {
	65	pr_devel("%s unable to get task %i\n",
	66	__func__, pid_nr(ctx->pid));
	67	return;
	68	}
	69
	70	if (task->mm != mm)
	71	goto out_put;
	72
	73	pr_devel("%s matched mm - card: %i afu: %i pe: %i\n", __func__,
	74	ctx->afu->adapter->adapter_num, ctx->afu->slice, ctx->pe);
	75
	76	spin_lock_irqsave(&ctx->sste_lock, flags);
9bcf28cd	77	trace_cxl_slbia(ctx);
f204e0b8 IM	78	memset(ctx->sstp, 0, ctx->sst_size);
	79	spin_unlock_irqrestore(&ctx->sste_lock, flags);
	80	mb();
	81	cxl_afu_slbia(ctx->afu);
	82	out_put:
	83	put_task_struct(task);
	84	}
	85
	86	static inline void cxl_slbia_core(struct mm_struct *mm)
	87	{
	88	struct cxl *adapter;
	89	struct cxl_afu *afu;
	90	struct cxl_context *ctx;
	91	int card, slice, id;
	92
	93	pr_devel("%s called\n", __func__);
	94
	95	spin_lock(&adapter_idr_lock);
	96	idr_for_each_entry(&cxl_adapter_idr, adapter, card) {
	97	/* XXX: Make this lookup faster with link from mm to ctx */
	98	spin_lock(&adapter->afu_list_lock);
	99	for (slice = 0; slice < adapter->slices; slice++) {
	100	afu = adapter->afu[slice];
2c069a11	101	if (!afu \|\| !afu->enabled)
f204e0b8 IM	102	continue;
	103	rcu_read_lock();
	104	idr_for_each_entry(&afu->contexts_idr, ctx, id)
	105	_cxl_slbia(ctx, mm);
	106	rcu_read_unlock();
	107	}
	108	spin_unlock(&adapter->afu_list_lock);
	109	}
	110	spin_unlock(&adapter_idr_lock);
	111	}
	112
	113	static struct cxl_calls cxl_calls = {
	114	.cxl_slbia = cxl_slbia_core,
a19bd79e IM	115	.cxl_pci_associate_default_context = _cxl_pci_associate_default_context,
a19bd79e IM	116	.cxl_pci_disable_device = _cxl_pci_disable_device,
cbce0917	117	.cxl_next_msi_hwirq = _cxl_next_msi_hwirq,
a2f67d5e IM	118	.cxl_cx4_setup_msi_irqs = _cxl_cx4_setup_msi_irqs,
a2f67d5e IM	119	.cxl_cx4_teardown_msi_irqs = _cxl_cx4_teardown_msi_irqs,
f204e0b8 IM	120	.owner = THIS_MODULE,
	121	};
	122
	123	int cxl_alloc_sst(struct cxl_context *ctx)
	124	{
	125	unsigned long vsid;
	126	u64 ea_mask, size, sstp0, sstp1;
	127
	128	sstp0 = 0;
	129	sstp1 = 0;
	130
	131	ctx->sst_size = PAGE_SIZE;
	132	ctx->sst_lru = 0;
	133	ctx->sstp = (struct cxl_sste *)get_zeroed_page(GFP_KERNEL);
	134	if (!ctx->sstp) {
	135	pr_err("cxl_alloc_sst: Unable to allocate segment table\n");
	136	return -ENOMEM;
	137	}
	138	pr_devel("SSTP allocated at 0x%p\n", ctx->sstp);
	139
	140	vsid = get_kernel_vsid((u64)ctx->sstp, mmu_kernel_ssize) << 12;
	141
	142	sstp0 \|= (u64)mmu_kernel_ssize << CXL_SSTP0_An_B_SHIFT;
	143	sstp0 \|= (SLB_VSID_KERNEL \| mmu_psize_defs[mmu_linear_psize].sllp) << 50;
	144
	145	size = (((u64)ctx->sst_size >> 8) - 1) << CXL_SSTP0_An_SegTableSize_SHIFT;
	146	if (unlikely(size & ~CXL_SSTP0_An_SegTableSize_MASK)) {
	147	WARN(1, "Impossible segment table size\n");
	148	return -EINVAL;
	149	}
	150	sstp0 \|= size;
	151
	152	if (mmu_kernel_ssize == MMU_SEGSIZE_256M)
	153	ea_mask = 0xfffff00ULL;
	154	else
	155	ea_mask = 0xffffffff00ULL;
	156
	157	sstp0 \|= vsid >> (50-14); /* Top 14 bits of VSID */
	158	sstp1 \|= (vsid << (64-(50-14))) & ~ea_mask;
	159	sstp1 \|= (u64)ctx->sstp & ea_mask;
	160	sstp1 \|= CXL_SSTP1_An_V;
	161
	162	pr_devel("Looked up %#llx: slbfee. %#llx (ssize: %x, vsid: %#lx), copied to SSTP0: %#llx, SSTP1: %#llx\n",
	163	(u64)ctx->sstp, (u64)ctx->sstp & ESID_MASK, mmu_kernel_ssize, vsid, sstp0, sstp1);
	164
	165	/* Store calculated sstp hardware points for use later */
	166	ctx->sstp0 = sstp0;
	167	ctx->sstp1 = sstp1;
	168
	169	return 0;
	170	}
	171
444c4ba4 CL	172	/* print buffer content as integers when debugging */
	173	void cxl_dump_debug_buffer(void *buf, size_t buf_len)
	174	{
	175	#ifdef DEBUG
	176	int i, *ptr;
	177
	178	/*
	179	* We want to regroup up to 4 integers per line, which means they
	180	* need to be in the same pr_devel() statement
	181	*/
	182	ptr = (int *) buf;
	183	for (i = 0; i * 4 < buf_len; i += 4) {
	184	if ((i + 3) * 4 < buf_len)
	185	pr_devel("%.8x %.8x %.8x %.8x\n", ptr[i], ptr[i + 1],
	186	ptr[i + 2], ptr[i + 3]);
	187	else if ((i + 2) * 4 < buf_len)
	188	pr_devel("%.8x %.8x %.8x\n", ptr[i], ptr[i + 1],
	189	ptr[i + 2]);
	190	else if ((i + 1) * 4 < buf_len)
	191	pr_devel("%.8x %.8x\n", ptr[i], ptr[i + 1]);
	192	else
	193	pr_devel("%.8x\n", ptr[i]);
	194	}
	195	#endif /* DEBUG */
	196	}
	197
f204e0b8 IM	198	/* Find a CXL adapter by it's number and increase it's refcount */
	199	struct cxl *get_cxl_adapter(int num)
	200	{
	201	struct cxl *adapter;
	202
	203	spin_lock(&adapter_idr_lock);
	204	if ((adapter = idr_find(&cxl_adapter_idr, num)))
	205	get_device(&adapter->dev);
	206	spin_unlock(&adapter_idr_lock);
	207
	208	return adapter;
	209	}
	210
d56d301b	211	static int cxl_alloc_adapter_nr(struct cxl *adapter)
f204e0b8 IM	212	{
	213	int i;
	214
	215	idr_preload(GFP_KERNEL);
	216	spin_lock(&adapter_idr_lock);
	217	i = idr_alloc(&cxl_adapter_idr, adapter, 0, 0, GFP_NOWAIT);
	218	spin_unlock(&adapter_idr_lock);
	219	idr_preload_end();
	220	if (i < 0)
	221	return i;
	222
	223	adapter->adapter_num = i;
	224
	225	return 0;
	226	}
	227
	228	void cxl_remove_adapter_nr(struct cxl *adapter)
	229	{
	230	idr_remove(&cxl_adapter_idr, adapter->adapter_num);
	231	}
	232
86331862 CL	233	struct cxl *cxl_alloc_adapter(void)
	234	{
	235	struct cxl *adapter;
	236
	237	if (!(adapter = kzalloc(sizeof(struct cxl), GFP_KERNEL)))
	238	return NULL;
	239
	240	spin_lock_init(&adapter->afu_list_lock);
	241
	242	if (cxl_alloc_adapter_nr(adapter))
	243	goto err1;
	244
	245	if (dev_set_name(&adapter->dev, "card%i", adapter->adapter_num))
	246	goto err2;
	247
70b565bb VJ	248	/* start with context lock taken */
70b565bb VJ	249	atomic_set(&adapter->contexts_num, -1);
86331862	250
70b565bb	251	return adapter;
86331862 CL	252	err2:
	253	cxl_remove_adapter_nr(adapter);
	254	err1:
	255	kfree(adapter);
	256	return NULL;
	257	}
	258
	259	struct cxl_afu cxl_alloc_afu(struct cxl adapter, int slice)
	260	{
	261	struct cxl_afu *afu;
	262
	263	if (!(afu = kzalloc(sizeof(struct cxl_afu), GFP_KERNEL)))
	264	return NULL;
	265
	266	afu->adapter = adapter;
	267	afu->dev.parent = &adapter->dev;
5be587b1	268	afu->dev.release = cxl_ops->release_afu;
86331862 CL	269	afu->slice = slice;
	270	idr_init(&afu->contexts_idr);
	271	mutex_init(&afu->contexts_lock);
	272	spin_lock_init(&afu->afu_cntl_lock);
171ed0fc	273	atomic_set(&afu->configured_state, -1);
86331862 CL	274	afu->prefault_mode = CXL_PREFAULT_NONE;
	275	afu->irqs_max = afu->adapter->user_irqs;
	276
	277	return afu;
	278	}
	279
f204e0b8 IM	280	int cxl_afu_select_best_mode(struct cxl_afu *afu)
	281	{
	282	if (afu->modes_supported & CXL_MODE_DIRECTED)
5be587b1	283	return cxl_ops->afu_activate_mode(afu, CXL_MODE_DIRECTED);
f204e0b8 IM	284
f204e0b8 IM	285	if (afu->modes_supported & CXL_MODE_DEDICATED)
5be587b1	286	return cxl_ops->afu_activate_mode(afu, CXL_MODE_DEDICATED);
f204e0b8 IM	287
	288	dev_warn(&afu->dev, "No supported programming modes available\n");
	289	/* We don't fail this so the user can inspect sysfs */
	290	return 0;
	291	}
	292
70b565bb VJ	293	int cxl_adapter_context_get(struct cxl *adapter)
	294	{
	295	int rc;
	296
	297	rc = atomic_inc_unless_negative(&adapter->contexts_num);
	298	return rc >= 0 ? 0 : -EBUSY;
	299	}
	300
	301	void cxl_adapter_context_put(struct cxl *adapter)
	302	{
	303	atomic_dec_if_positive(&adapter->contexts_num);
	304	}
	305
	306	int cxl_adapter_context_lock(struct cxl *adapter)
	307	{
	308	int rc;
	309	/* no active contexts -> contexts_num == 0 */
	310	rc = atomic_cmpxchg(&adapter->contexts_num, 0, -1);
	311	return rc ? -EBUSY : 0;
	312	}
	313
	314	void cxl_adapter_context_unlock(struct cxl *adapter)
	315	{
	316	int val = atomic_cmpxchg(&adapter->contexts_num, -1, 0);
	317
	318	/*
	319	* contexts lock taken -> contexts_num == -1
	320	* If not true then show a warning and force reset the lock.
	321	* This will happen when context_unlock was requested without
	322	* doing a context_lock.
	323	*/
	324	if (val != -1) {
	325	atomic_set(&adapter->contexts_num, 0);
	326	WARN(1, "Adapter context unlocked with %d active contexts",
	327	val);
	328	}
	329	}
	330
f204e0b8 IM	331	static int __init init_cxl(void)
	332	{
	333	int rc = 0;
	334
f204e0b8 IM	335	if ((rc = cxl_file_init()))
	336	return rc;
	337
	338	cxl_debugfs_init();
	339
	340	if ((rc = register_cxl_calls(&cxl_calls)))
	341	goto err;
	342
14baf4d9 CL	343	if (cpu_has_feature(CPU_FTR_HVMODE)) {
	344	cxl_ops = &cxl_native_ops;
	345	rc = pci_register_driver(&cxl_pci_driver);
	346	}
	347	#ifdef CONFIG_PPC_PSERIES
	348	else {
	349	cxl_ops = &cxl_guest_ops;
	350	rc = platform_driver_register(&cxl_of_driver);
	351	}
	352	#endif
	353	if (rc)
f204e0b8 IM	354	goto err1;
	355
	356	return 0;
	357	err1:
	358	unregister_cxl_calls(&cxl_calls);
	359	err:
	360	cxl_debugfs_exit();
	361	cxl_file_exit();
	362
	363	return rc;
	364	}
	365
	366	static void exit_cxl(void)
	367	{
14baf4d9 CL	368	if (cpu_has_feature(CPU_FTR_HVMODE))
	369	pci_unregister_driver(&cxl_pci_driver);
	370	#ifdef CONFIG_PPC_PSERIES
	371	else
	372	platform_driver_unregister(&cxl_of_driver);
	373	#endif
f204e0b8 IM	374
	375	cxl_debugfs_exit();
	376	cxl_file_exit();
	377	unregister_cxl_calls(&cxl_calls);
b2a02ac6	378	idr_destroy(&cxl_adapter_idr);
f204e0b8 IM	379	}
	380
	381	module_init(init_cxl);
	382	module_exit(exit_cxl);
	383
	384	MODULE_DESCRIPTION("IBM Coherent Accelerator");
	385	MODULE_AUTHOR("Ian Munsie <imunsie@au1.ibm.com>");
	386	MODULE_LICENSE("GPL");