linux/drivers/misc/cxl/main.c

234 lines
5.4 KiB
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 <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");
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,
.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);
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");