linux/drivers/misc/cxl/irq.c

515 lines
14 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/interrupt.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"
/* XXX: This is implementation specific */
static irqreturn_t handle_psl_slice_error(struct cxl_context *ctx, u64 dsisr, u64 errstat)
{
u64 fir1, fir2, fir_slice, serr, afu_debug;
fir1 = cxl_p1_read(ctx->afu->adapter, CXL_PSL_FIR1);
fir2 = cxl_p1_read(ctx->afu->adapter, CXL_PSL_FIR2);
fir_slice = cxl_p1n_read(ctx->afu, CXL_PSL_FIR_SLICE_An);
serr = cxl_p1n_read(ctx->afu, CXL_PSL_SERR_An);
afu_debug = cxl_p1n_read(ctx->afu, CXL_AFU_DEBUG_An);
dev_crit(&ctx->afu->dev, "PSL ERROR STATUS: 0x%.16llx\n", errstat);
dev_crit(&ctx->afu->dev, "PSL_FIR1: 0x%.16llx\n", fir1);
dev_crit(&ctx->afu->dev, "PSL_FIR2: 0x%.16llx\n", fir2);
dev_crit(&ctx->afu->dev, "PSL_SERR_An: 0x%.16llx\n", serr);
dev_crit(&ctx->afu->dev, "PSL_FIR_SLICE_An: 0x%.16llx\n", fir_slice);
dev_crit(&ctx->afu->dev, "CXL_PSL_AFU_DEBUG_An: 0x%.16llx\n", afu_debug);
dev_crit(&ctx->afu->dev, "STOPPING CXL TRACE\n");
cxl_stop_trace(ctx->afu->adapter);
return cxl_ack_irq(ctx, 0, errstat);
}
irqreturn_t cxl_slice_irq_err(int irq, void *data)
{
struct cxl_afu *afu = data;
u64 fir_slice, errstat, serr, afu_debug;
WARN(irq, "CXL SLICE ERROR interrupt %i\n", irq);
serr = cxl_p1n_read(afu, CXL_PSL_SERR_An);
fir_slice = cxl_p1n_read(afu, CXL_PSL_FIR_SLICE_An);
errstat = cxl_p2n_read(afu, CXL_PSL_ErrStat_An);
afu_debug = cxl_p1n_read(afu, CXL_AFU_DEBUG_An);
dev_crit(&afu->dev, "PSL_SERR_An: 0x%.16llx\n", serr);
dev_crit(&afu->dev, "PSL_FIR_SLICE_An: 0x%.16llx\n", fir_slice);
dev_crit(&afu->dev, "CXL_PSL_ErrStat_An: 0x%.16llx\n", errstat);
dev_crit(&afu->dev, "CXL_PSL_AFU_DEBUG_An: 0x%.16llx\n", afu_debug);
cxl_p1n_write(afu, CXL_PSL_SERR_An, serr);
return IRQ_HANDLED;
}
static irqreturn_t cxl_irq_err(int irq, void *data)
{
struct cxl *adapter = data;
u64 fir1, fir2, err_ivte;
WARN(1, "CXL ERROR interrupt %i\n", irq);
err_ivte = cxl_p1_read(adapter, CXL_PSL_ErrIVTE);
dev_crit(&adapter->dev, "PSL_ErrIVTE: 0x%.16llx\n", err_ivte);
dev_crit(&adapter->dev, "STOPPING CXL TRACE\n");
cxl_stop_trace(adapter);
fir1 = cxl_p1_read(adapter, CXL_PSL_FIR1);
fir2 = cxl_p1_read(adapter, CXL_PSL_FIR2);
dev_crit(&adapter->dev, "PSL_FIR1: 0x%.16llx\nPSL_FIR2: 0x%.16llx\n", fir1, fir2);
return IRQ_HANDLED;
}
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;
}
static irqreturn_t cxl_irq(int irq, void *data, struct cxl_irq_info *irq_info)
{
struct cxl_context *ctx = data;
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 handle_psl_slice_error(ctx, dsisr, irq_info->errstat);
if (dsisr & CXL_PSL_DSISR_An_AE) {
pr_devel("CXL interrupt: AFU Error %.llx\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: %.llx\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_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 fail_psl_irq(struct cxl_afu *afu, struct cxl_irq_info *irq_info)
{
if (irq_info->dsisr & CXL_PSL_DSISR_TRANS)
cxl_p2n_write(afu, CXL_PSL_TFC_An, CXL_PSL_TFC_An_AE);
else
cxl_p2n_write(afu, CXL_PSL_TFC_An, CXL_PSL_TFC_An_A);
return IRQ_HANDLED;
}
static irqreturn_t cxl_irq_multiplexed(int irq, void *data)
{
struct cxl_afu *afu = data;
struct cxl_context *ctx;
struct cxl_irq_info irq_info;
int ph = cxl_p2n_read(afu, CXL_PSL_PEHandle_An) & 0xffff;
int ret;
if ((ret = cxl_get_irq(afu, &irq_info))) {
WARN(1, "Unable to get CXL IRQ Info: %i\n", ret);
return fail_psl_irq(afu, &irq_info);
}
rcu_read_lock();
ctx = idr_find(&afu->contexts_idr, ph);
if (ctx) {
ret = cxl_irq(irq, ctx, &irq_info);
rcu_read_unlock();
return ret;
}
rcu_read_unlock();
WARN(1, "Unable to demultiplex CXL PSL IRQ for PE %i DSISR %.16llx DAR"
" %.16llx\n(Possible AFU HW issue - was a term/remove acked"
" with outstanding transactions?)\n", ph, irq_info.dsisr,
irq_info.dar);
return fail_psl_irq(afu, &irq_info);
}
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 = 1;
__u16 range;
int r;
for (r = 1; 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, "Recieved 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, "Recieved 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;
}
cxl_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);
irq_dispose_mapping(virq);
}
static 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_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_release_one_irq(adapter, hwirq);
return -ENOMEM;
}
int cxl_register_psl_err_irq(struct cxl *adapter)
{
int rc;
adapter->irq_name = kasprintf(GFP_KERNEL, "cxl-%s-err",
dev_name(&adapter->dev));
if (!adapter->irq_name)
return -ENOMEM;
if ((rc = cxl_register_one_irq(adapter, cxl_irq_err, adapter,
&adapter->err_hwirq,
&adapter->err_virq,
adapter->irq_name))) {
kfree(adapter->irq_name);
adapter->irq_name = NULL;
return rc;
}
cxl_p1_write(adapter, CXL_PSL_ErrIVTE, adapter->err_hwirq & 0xffff);
return 0;
}
void cxl_release_psl_err_irq(struct cxl *adapter)
{
cxl_p1_write(adapter, CXL_PSL_ErrIVTE, 0x0000000000000000);
cxl_unmap_irq(adapter->err_virq, adapter);
cxl_release_one_irq(adapter, adapter->err_hwirq);
kfree(adapter->irq_name);
}
int cxl_register_serr_irq(struct cxl_afu *afu)
{
u64 serr;
int rc;
afu->err_irq_name = kasprintf(GFP_KERNEL, "cxl-%s-err",
dev_name(&afu->dev));
if (!afu->err_irq_name)
return -ENOMEM;
if ((rc = cxl_register_one_irq(afu->adapter, cxl_slice_irq_err, afu,
&afu->serr_hwirq,
&afu->serr_virq, afu->err_irq_name))) {
kfree(afu->err_irq_name);
afu->err_irq_name = NULL;
return rc;
}
serr = cxl_p1n_read(afu, CXL_PSL_SERR_An);
serr = (serr & 0x00ffffffffff0000ULL) | (afu->serr_hwirq & 0xffff);
cxl_p1n_write(afu, CXL_PSL_SERR_An, serr);
return 0;
}
void cxl_release_serr_irq(struct cxl_afu *afu)
{
cxl_p1n_write(afu, CXL_PSL_SERR_An, 0x0000000000000000);
cxl_unmap_irq(afu->serr_virq, afu);
cxl_release_one_irq(afu->adapter, afu->serr_hwirq);
kfree(afu->err_irq_name);
}
int cxl_register_psl_irq(struct cxl_afu *afu)
{
int rc;
afu->psl_irq_name = kasprintf(GFP_KERNEL, "cxl-%s",
dev_name(&afu->dev));
if (!afu->psl_irq_name)
return -ENOMEM;
if ((rc = cxl_register_one_irq(afu->adapter, cxl_irq_multiplexed, afu,
&afu->psl_hwirq, &afu->psl_virq,
afu->psl_irq_name))) {
kfree(afu->psl_irq_name);
afu->psl_irq_name = NULL;
}
return rc;
}
void cxl_release_psl_irq(struct cxl_afu *afu)
{
cxl_unmap_irq(afu->psl_virq, afu);
cxl_release_one_irq(afu->adapter, afu->psl_hwirq);
kfree(afu->psl_irq_name);
}
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;
if ((rc = cxl_alloc_irq_ranges(&ctx->irqs, ctx->afu->adapter, count)))
return rc;
/* Multiplexed PSL Interrupt */
ctx->irqs.offset[0] = ctx->afu->psl_hwirq;
ctx->irqs.range[0] = 1;
ctx->irq_count = count;
ctx->irq_bitmap = kcalloc(BITS_TO_LONGS(count),
sizeof(*ctx->irq_bitmap), GFP_KERNEL);
if (!ctx->irq_bitmap)
return -ENOMEM;
/*
* Allocate names first. If any fail, bail out before allocating
* actual hardware IRQs.
*/
INIT_LIST_HEAD(&ctx->irq_names);
for (r = 1; 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:
afu_irq_name_free(ctx);
return -ENOMEM;
}
void afu_register_hwirqs(struct cxl_context *ctx)
{
irq_hw_number_t hwirq;
struct cxl_irq_name *irq_name;
int r,i;
/* 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 = 1; r < CXL_IRQ_RANGES; r++) {
hwirq = ctx->irqs.offset[r];
for (i = 0; i < ctx->irqs.range[r]; hwirq++, i++) {
cxl_map_irq(ctx->afu->adapter, hwirq,
cxl_irq_afu, 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 = 1; 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_release_irq_ranges(&ctx->irqs, ctx->afu->adapter);
}