// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright 2014 IBM Corp.
*/
#include <linux/interrupt.h>
#include <linux/irqdomain.h>
#include <linux/workqueue.h>
#include <linux/sched.h>
#include <linux/wait.h>
#include <linux/slab.h>
#include <linux/pid.h>
#include <asm/cputable.h>
#include <misc/cxl-base.h>
#include "cxl.h"
#include "trace.h"
static int afu_irq_range_start(void)
{
if (cpu_has_feature(CPU_FTR_HVMODE))
return 1;
return 0;
}
static irqreturn_t schedule_cxl_fault(struct cxl_context *ctx, u64 dsisr, u64 dar)
{
ctx->dsisr = dsisr;
ctx->dar = dar;
schedule_work(&ctx->fault_work);
return IRQ_HANDLED;
}
irqreturn_t cxl_irq_psl9(int irq, struct cxl_context *ctx, struct cxl_irq_info *irq_info)
{
u64 dsisr, dar;
dsisr = irq_info->dsisr;
dar = irq_info->dar;
trace_cxl_psl9_irq(ctx, irq, dsisr, dar);
pr_devel("CXL interrupt %i for afu pe: %i DSISR: %#llx DAR: %#llx\n", irq, ctx->pe, dsisr, dar);
if (dsisr & CXL_PSL9_DSISR_An_TF) {
pr_devel("CXL interrupt: Scheduling translation fault handling for later (pe: %i)\n", ctx->pe);
return schedule_cxl_fault(ctx, dsisr, dar);
}
if (dsisr & CXL_PSL9_DSISR_An_PE)
return cxl_ops->handle_psl_slice_error(ctx, dsisr,
irq_info->errstat);
if (dsisr & CXL_PSL9_DSISR_An_AE) {
pr_devel("CXL interrupt: AFU Error 0x%016llx\n", irq_info->afu_err);
if (ctx->pending_afu_err) {
/*
* This shouldn't happen - the PSL treats these errors
* as fatal and will have reset the AFU, so there's not
* much point buffering multiple AFU errors.
* OTOH if we DO ever see a storm of these come in it's
* probably best that we log them somewhere:
*/
dev_err_ratelimited(&ctx->afu->dev, "CXL AFU Error undelivered to pe %i: 0x%016llx\n",
ctx->pe, irq_info->afu_err);
} else {
spin_lock(&ctx->lock);
ctx->afu_err = irq_info->afu_err;
ctx->pending_afu_err = 1;
spin_unlock(&ctx->lock);
wake_up_all(&ctx->wq);
}
cxl_ops->ack_irq(ctx, CXL_PSL_TFC_An_A, 0);
return IRQ_HANDLED;
}
if (dsisr & CXL_PSL9_DSISR_An_OC)
pr_devel("CXL interrupt: OS Context Warning\n");
WARN(1, "Unhandled CXL PSL IRQ\n");
return IRQ_HANDLED;
}
irqreturn_t cxl_irq_psl8(int irq, struct cxl_context *ctx, struct cxl_irq_info *irq_info)
{
u64 dsisr, dar;
dsisr = irq_info->dsisr;
dar = irq_info->dar;
trace_cxl_psl_irq(ctx, irq, dsisr, dar);
pr_devel("CXL interrupt %i for afu pe: %i DSISR: %#llx DAR: %#llx\n", irq, ctx->pe, dsisr, dar);
if (dsisr & CXL_PSL_DSISR_An_DS) {
/*
* We don't inherently need to sleep to handle this, but we do
* need to get a ref to the task's mm, which we can't do from
* irq context without the potential for a deadlock since it
* takes the task_lock. An alternate option would be to keep a
* reference to the task's mm the entire time it has cxl open,
* but to do that we need to solve the issue where we hold a
* ref to the mm, but the mm can hold a ref to the fd after an
* mmap preventing anything from being cleaned up.
*/
pr_devel("Scheduling segment miss handling for later pe: %i\n", ctx->pe);
return schedule_cxl_fault(ctx, dsisr, dar);
}
if (dsisr & CXL_PSL_DSISR_An_M)
pr_devel("CXL interrupt: PTE not found\n");
if (dsisr & CXL_PSL_DSISR_An_P)
pr_devel("CXL interrupt: Storage protection violation\n");
if (dsisr & CXL_PSL_DSISR_An_A)
pr_devel("CXL interrupt: AFU lock access to write through or cache inhibited storage\n");
if (dsisr & CXL_PSL_DSISR_An_S)
pr_devel("CXL interrupt: Access was afu_wr or afu_zero\n");
if (dsisr & CXL_PSL_DSISR_An_K)
pr_devel("CXL interrupt: Access not permitted by virtual page class key protection\n");
if (dsisr & CXL_PSL_DSISR_An_DM) {
/*
* In some cases we might be able to handle the fault
* immediately if hash_page would succeed, but we still need
* the task's mm, which as above we can't get without a lock
*/
pr_devel("Scheduling page fault handling for later pe: %i\n", ctx->pe);
return schedule_cxl_fault(ctx, dsisr, dar);
}
if (dsisr & CXL_PSL_DSISR_An_ST)
WARN(1, "CXL interrupt: Segment Table PTE not found\n");
if (dsisr & CXL_PSL_DSISR_An_UR)
pr_devel("CXL interrupt: AURP PTE not found\n");
if (dsisr & CXL_PSL_DSISR_An_PE)
return cxl_ops->handle_psl_slice_error(ctx, dsisr,
irq_info->errstat);
if (dsisr & CXL_PSL_DSISR_An_AE) {
pr_devel("CXL interrupt: AFU Error 0x%016llx\n", irq_info->afu_err);
if (ctx->pending_afu_err) {
/*
* This shouldn't happen - the PSL treats these errors
* as fatal and will have reset the AFU, so there's not
* much point buffering multiple AFU errors.
* OTOH if we DO ever see a storm of these come in it's
* probably best that we log them somewhere:
*/
dev_err_ratelimited(&ctx->afu->dev, "CXL AFU Error "
"undelivered to pe %i: 0x%016llx\n",
ctx->pe, irq_info->afu_err);
} else {
spin_lock(&ctx->lock);
ctx->afu_err = irq_info->afu_err;
ctx->pending_afu_err = true;
spin_unlock(&ctx->lock);
wake_up_all(&ctx->wq);
}
cxl_ops->ack_irq(ctx, CXL_PSL_TFC_An_A, 0);
return IRQ_HANDLED;
}
if (dsisr & CXL_PSL_DSISR_An_OC)
pr_devel("CXL interrupt: OS Context Warning\n");
WARN(1, "Unhandled CXL PSL IRQ\n");
return IRQ_HANDLED;
}
static irqreturn_t cxl_irq_afu(int irq, void *data)
{
struct cxl_context *ctx = data;
irq_hw_number_t hwirq = irqd_to_hwirq(irq_get_irq_data(irq));
int irq_off, afu_irq = 0;
__u16 range;
int r;
/*
* Look for the interrupt number.
* On bare-metal, we know range 0 only contains the PSL
* interrupt so we could start counting at range 1 and initialize
* afu_irq at 1.
* In a guest, range 0 also contains AFU interrupts, so it must
* be counted for. Therefore we initialize afu_irq at 0 to take into
* account the PSL interrupt.
*
* For code-readability, it just seems easier to go over all
* the ranges on bare-metal and guest. The end result is the same.
*/
for (r = 0; r < CXL_IRQ_RANGES; r++) {
irq_off = hwirq - ctx->irqs.offset[r];
range = ctx->irqs.range[r];
if (irq_off >= 0 && irq_off < range) {
afu_irq += irq_off;
break;
}
afu_irq += range;
}
if (unlikely(r >= CXL_IRQ_RANGES)) {
WARN(1, "Received AFU IRQ out of range for pe %i (virq %i hwirq %lx)\n",
ctx->pe, irq, hwirq);
return IRQ_HANDLED;
}
trace_cxl_afu_irq(ctx, afu_irq, irq, hwirq);
pr_devel("Received AFU interrupt %i for pe: %i (virq %i hwirq %lx)\n",
afu_irq, ctx->pe, irq, hwirq);
if (unlikely(!ctx->irq_bitmap)) {
WARN(1, "Received AFU IRQ for context with no IRQ bitmap\n");
return IRQ_HANDLED;
}
spin_lock(&ctx->lock);
set_bit(afu_irq - 1, ctx->irq_bitmap);
ctx->pending_irq = true;
spin_unlock(&ctx->lock);
wake_up_all(&ctx->wq);
return IRQ_HANDLED;
}
unsigned int cxl_map_irq(struct cxl *adapter, irq_hw_number_t hwirq,
irq_handler_t handler, void *cookie, const char *name)
{
unsigned int virq;
int result;
/* IRQ Domain? */
virq = irq_create_mapping(NULL, hwirq);
if (!virq) {
dev_warn(&adapter->dev, "cxl_map_irq: irq_create_mapping failed\n");
return 0;
}
if (cxl_ops->setup_irq)
cxl_ops->setup_irq(adapter, hwirq, virq);
pr_devel("hwirq %#lx mapped to virq %u\n", hwirq, virq);
result = request_irq(virq, handler, 0, name, cookie);
if (result) {
dev_warn(&adapter->dev, "cxl_map_irq: request_irq failed: %i\n", result);
return 0;
}
return virq;
}
void cxl_unmap_irq(unsigned int virq, void *cookie)
{
free_irq(virq, cookie);
}
int cxl_register_one_irq(struct cxl *adapter,
irq_handler_t handler,
void *cookie,
irq_hw_number_t *dest_hwirq,
unsigned int *dest_virq,
const char *name)
{
int hwirq, virq;
if ((hwirq = cxl_ops->alloc_one_irq(adapter)) < 0)
return hwirq;
if (!(virq = cxl_map_irq(adapter, hwirq, handler, cookie, name)))
goto err;
*dest_hwirq = hwirq;
*dest_virq = virq;
return 0;
err:
cxl_ops->release_one_irq(adapter, hwirq);
return -ENOMEM;
}
void afu_irq_name_free(struct cxl_context *ctx)
{
struct cxl_irq_name *irq_name, *tmp;
list_for_each_entry_safe(irq_name, tmp, &ctx->irq_names, list) {
kfree(irq_name->name);
list_del(&irq_name->list);
kfree(irq_name);
}
}
int afu_allocate_irqs(struct cxl_context *ctx, u32 count)
{
int rc, r, i, j = 1;
struct cxl_irq_name *irq_name;
int alloc_count;
/*
* In native mode, range 0 is reserved for the multiplexed
* PSL interrupt. It has been allocated when the AFU was initialized.
*
* In a guest, the PSL interrupt is not mutliplexed, but per-context,
* and is the first interrupt from range 0. It still needs to be
* allocated, so bump the count by one.
*/
if (cpu_has_feature(CPU_FTR_HVMODE))
alloc_count = count;
else
alloc_count = count + 1;
if ((rc = cxl_ops->alloc_irq_ranges(&ctx->irqs, ctx->afu->adapter,
alloc_count)))
return rc;
if (cpu_has_feature(CPU_FTR_HVMODE)) {
/* Multiplexed PSL Interrupt */
ctx->irqs.offset[0] = ctx->afu->native->psl_hwirq;
ctx->irqs.range[0] = 1;
}
ctx->irq_count = count;
ctx->irq_bitmap = bitmap_zalloc(count, GFP_KERNEL);
if (!ctx->irq_bitmap)
goto out;
/*
* Allocate names first. If any fail, bail out before allocating
* actual hardware IRQs.
*/
for (r = afu_irq_range_start(); r < CXL_IRQ_RANGES; r++) {
for (i = 0; i < ctx->irqs.range[r]; i++) {
irq_name = kmalloc(sizeof(struct cxl_irq_name),
GFP_KERNEL);
if (!irq_name)
goto out;
irq_name->name = kasprintf(GFP_KERNEL, "cxl-%s-pe%i-%i",
dev_name(&ctx->afu->dev),
ctx->pe, j);
if (!irq_name->name) {
kfree(irq_name);
goto out;
}
/* Add to tail so next look get the correct order */
list_add_tail(&irq_name->list, &ctx->irq_names);
j++;
}
}
return 0;
out:
cxl_ops->release_irq_ranges(&ctx->irqs, ctx->afu->adapter);
bitmap_free(ctx->irq_bitmap);
afu_irq_name_free(ctx);
return -ENOMEM;
}
static void afu_register_hwirqs(struct cxl_context *ctx)
{
irq_hw_number_t hwirq;
struct cxl_irq_name *irq_name;
int r, i;
irqreturn_t (*handler)(int irq, void *data);
/* We've allocated all memory now, so let's do the irq allocations */
irq_name = list_first_entry(&ctx->irq_names, struct cxl_irq_name, list);
for (r = afu_irq_range_start(); r < CXL_IRQ_RANGES; r++) {
hwirq = ctx->irqs.offset[r];
for (i = 0; i < ctx->irqs.range[r]; hwirq++, i++) {
if (r == 0 && i == 0)
/*
* The very first interrupt of range 0 is
* always the PSL interrupt, but we only
* need to connect a handler for guests,
* because there's one PSL interrupt per
* context.
* On bare-metal, the PSL interrupt is
* multiplexed and was setup when the AFU
* was configured.
*/
handler = cxl_ops->psl_interrupt;
else
handler = cxl_irq_afu;
cxl_map_irq(ctx->afu->adapter, hwirq, handler, ctx,
irq_name->name);
irq_name = list_next_entry(irq_name, list);
}
}
}
int afu_register_irqs(struct cxl_context *ctx, u32 count)
{
int rc;
rc = afu_allocate_irqs(ctx, count);
if (rc)
return rc;
afu_register_hwirqs(ctx);
return 0;
}
void afu_release_irqs(struct cxl_context *ctx, void *cookie)
{
irq_hw_number_t hwirq;
unsigned int virq;
int r, i;
for (r = afu_irq_range_start(); r < CXL_IRQ_RANGES; r++) {
hwirq = ctx->irqs.offset[r];
for (i = 0; i < ctx->irqs.range[r]; hwirq++, i++) {
virq = irq_find_mapping(NULL, hwirq);
if (virq)
cxl_unmap_irq(virq, cookie);
}
}
afu_irq_name_free(ctx);
cxl_ops->release_irq_ranges(&ctx->irqs, ctx->afu->adapter);
ctx->irq_count = 0;
}
void cxl_afu_decode_psl_serr(struct cxl_afu *afu, u64 serr)
{
dev_crit(&afu->dev,
"PSL Slice error received. Check AFU for root cause.\n");
dev_crit(&afu->dev, "PSL_SERR_An: 0x%016llx\n", serr);
if (serr & CXL_PSL_SERR_An_afuto)
dev_crit(&afu->dev, "AFU MMIO Timeout\n");
if (serr & CXL_PSL_SERR_An_afudis)
dev_crit(&afu->dev,
"MMIO targeted Accelerator that was not enabled\n");
if (serr & CXL_PSL_SERR_An_afuov)
dev_crit(&afu->dev, "AFU CTAG Overflow\n");
if (serr & CXL_PSL_SERR_An_badsrc)
dev_crit(&afu->dev, "Bad Interrupt Source\n");
if (serr & CXL_PSL_SERR_An_badctx)
dev_crit(&afu->dev, "Bad Context Handle\n");
if (serr & CXL_PSL_SERR_An_llcmdis)
dev_crit(&afu->dev, "LLCMD to Disabled AFU\n");
if (serr & CXL_PSL_SERR_An_llcmdto)
dev_crit(&afu->dev, "LLCMD Timeout to AFU\n");
if (serr & CXL_PSL_SERR_An_afupar)
dev_crit(&afu->dev, "AFU MMIO Parity Error\n");
if (serr & CXL_PSL_SERR_An_afudup)
dev_crit(&afu->dev, "AFU MMIO Duplicate CTAG Error\n");
if (serr & CXL_PSL_SERR_An_AE)
dev_crit(&afu->dev,
"AFU asserted JDONE with JERROR in AFU Directed Mode\n");
}
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