// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Low-level SPU handling
*
* (C) Copyright IBM Deutschland Entwicklung GmbH 2005
*
* Author: Arnd Bergmann <[email protected]>
*/
#undef DEBUG
#include <linux/interrupt.h>
#include <linux/list.h>
#include <linux/init.h>
#include <linux/ptrace.h>
#include <linux/slab.h>
#include <linux/wait.h>
#include <linux/mm.h>
#include <linux/io.h>
#include <linux/mutex.h>
#include <linux/linux_logo.h>
#include <linux/syscore_ops.h>
#include <asm/spu.h>
#include <asm/spu_priv1.h>
#include <asm/spu_csa.h>
#include <asm/xmon.h>
#include <asm/kexec.h>
const struct spu_management_ops *spu_management_ops;
EXPORT_SYMBOL_GPL(spu_management_ops);
const struct spu_priv1_ops *spu_priv1_ops;
EXPORT_SYMBOL_GPL(spu_priv1_ops);
struct cbe_spu_info cbe_spu_info[MAX_NUMNODES];
EXPORT_SYMBOL_GPL(cbe_spu_info);
/*
* The spufs fault-handling code needs to call force_sig_fault to raise signals
* on DMA errors. Export it here to avoid general kernel-wide access to this
* function
*/
EXPORT_SYMBOL_GPL(force_sig_fault);
/*
* Protects cbe_spu_info and spu->number.
*/
static DEFINE_SPINLOCK(spu_lock);
/*
* List of all spus in the system.
*
* This list is iterated by callers from irq context and callers that
* want to sleep. Thus modifications need to be done with both
* spu_full_list_lock and spu_full_list_mutex held, while iterating
* through it requires either of these locks.
*
* In addition spu_full_list_lock protects all assignments to
* spu->mm.
*/
static LIST_HEAD(spu_full_list);
static DEFINE_SPINLOCK(spu_full_list_lock);
static DEFINE_MUTEX(spu_full_list_mutex);
void spu_invalidate_slbs(struct spu *spu)
{
struct spu_priv2 __iomem *priv2 = spu->priv2;
unsigned long flags;
spin_lock_irqsave(&spu->register_lock, flags);
if (spu_mfc_sr1_get(spu) & MFC_STATE1_RELOCATE_MASK)
out_be64(&priv2->slb_invalidate_all_W, 0UL);
spin_unlock_irqrestore(&spu->register_lock, flags);
}
EXPORT_SYMBOL_GPL(spu_invalidate_slbs);
/* This is called by the MM core when a segment size is changed, to
* request a flush of all the SPEs using a given mm
*/
void spu_flush_all_slbs(struct mm_struct *mm)
{
struct spu *spu;
unsigned long flags;
spin_lock_irqsave(&spu_full_list_lock, flags);
list_for_each_entry(spu, &spu_full_list, full_list) {
if (spu->mm == mm)
spu_invalidate_slbs(spu);
}
spin_unlock_irqrestore(&spu_full_list_lock, flags);
}
/* The hack below stinks... try to do something better one of
* these days... Does it even work properly with NR_CPUS == 1 ?
*/
static inline void mm_needs_global_tlbie(struct mm_struct *mm)
{
int nr = (NR_CPUS > 1) ? NR_CPUS : NR_CPUS + 1;
/* Global TLBIE broadcast required with SPEs. */
bitmap_fill(cpumask_bits(mm_cpumask(mm)), nr);
}
void spu_associate_mm(struct spu *spu, struct mm_struct *mm)
{
unsigned long flags;
spin_lock_irqsave(&spu_full_list_lock, flags);
spu->mm = mm;
spin_unlock_irqrestore(&spu_full_list_lock, flags);
if (mm)
mm_needs_global_tlbie(mm);
}
EXPORT_SYMBOL_GPL(spu_associate_mm);
int spu_64k_pages_available(void)
{
return mmu_psize_defs[MMU_PAGE_64K].shift != 0;
}
EXPORT_SYMBOL_GPL(spu_64k_pages_available);
static void spu_restart_dma(struct spu *spu)
{
struct spu_priv2 __iomem *priv2 = spu->priv2;
if (!test_bit(SPU_CONTEXT_SWITCH_PENDING, &spu->flags))
out_be64(&priv2->mfc_control_RW, MFC_CNTL_RESTART_DMA_COMMAND);
else {
set_bit(SPU_CONTEXT_FAULT_PENDING, &spu->flags);
mb();
}
}
static inline void spu_load_slb(struct spu *spu, int slbe, struct copro_slb *slb)
{
struct spu_priv2 __iomem *priv2 = spu->priv2;
pr_debug("%s: adding SLB[%d] 0x%016llx 0x%016llx\n",
__func__, slbe, slb->vsid, slb->esid);
out_be64(&priv2->slb_index_W, slbe);
/* set invalid before writing vsid */
out_be64(&priv2->slb_esid_RW, 0);
/* now it's safe to write the vsid */
out_be64(&priv2->slb_vsid_RW, slb->vsid);
/* setting the new esid makes the entry valid again */
out_be64(&priv2->slb_esid_RW, slb->esid);
}
static int __spu_trap_data_seg(struct spu *spu, unsigned long ea)
{
struct copro_slb slb;
int ret;
ret = copro_calculate_slb(spu->mm, ea, &slb);
if (ret)
return ret;
spu_load_slb(spu, spu->slb_replace, &slb);
spu->slb_replace++;
if (spu->slb_replace >= 8)
spu->slb_replace = 0;
spu_restart_dma(spu);
spu->stats.slb_flt++;
return 0;
}
extern int hash_page(unsigned long ea, unsigned long access,
unsigned long trap, unsigned long dsisr); //XXX
static int __spu_trap_data_map(struct spu *spu, unsigned long ea, u64 dsisr)
{
int ret;
pr_debug("%s, %llx, %lx\n", __func__, dsisr, ea);
/*
* Handle kernel space hash faults immediately. User hash
* faults need to be deferred to process context.
*/
if ((dsisr & MFC_DSISR_PTE_NOT_FOUND) &&
(get_region_id(ea) != USER_REGION_ID)) {
spin_unlock(&spu->register_lock);
ret = hash_page(ea,
_PAGE_PRESENT | _PAGE_READ | _PAGE_PRIVILEGED,
0x300, dsisr);
spin_lock(&spu->register_lock);
if (!ret) {
spu_restart_dma(spu);
return 0;
}
}
spu->class_1_dar = ea;
spu->class_1_dsisr = dsisr;
spu->stop_callback(spu, 1);
spu->class_1_dar = 0;
spu->class_1_dsisr = 0;
return 0;
}
static void __spu_kernel_slb(void *addr, struct copro_slb *slb)
{
unsigned long ea = (unsigned long)addr;
u64 llp;
if (get_region_id(ea) == LINEAR_MAP_REGION_ID)
llp = mmu_psize_defs[mmu_linear_psize].sllp;
else
llp = mmu_psize_defs[mmu_virtual_psize].sllp;
slb->vsid = (get_kernel_vsid(ea, MMU_SEGSIZE_256M) << SLB_VSID_SHIFT) |
SLB_VSID_KERNEL | llp;
slb->esid = (ea & ESID_MASK) | SLB_ESID_V;
}
/**
* Given an array of @nr_slbs SLB entries, @slbs, return non-zero if the
* address @new_addr is present.
*/
static inline int __slb_present(struct copro_slb *slbs, int nr_slbs,
void *new_addr)
{
unsigned long ea = (unsigned long)new_addr;
int i;
for (i = 0; i < nr_slbs; i++)
if (!((slbs[i].esid ^ ea) & ESID_MASK))
return 1;
return 0;
}
/**
* Setup the SPU kernel SLBs, in preparation for a context save/restore. We
* need to map both the context save area, and the save/restore code.
*
* Because the lscsa and code may cross segment boundaries, we check to see
* if mappings are required for the start and end of each range. We currently
* assume that the mappings are smaller that one segment - if not, something
* is seriously wrong.
*/
void spu_setup_kernel_slbs(struct spu *spu, struct spu_lscsa *lscsa,
void *code, int code_size)
{
struct copro_slb slbs[4];
int i, nr_slbs = 0;
/* start and end addresses of both mappings */
void *addrs[] = {
lscsa, (void *)lscsa + sizeof(*lscsa) - 1,
code, code + code_size - 1
};
/* check the set of addresses, and create a new entry in the slbs array
* if there isn't already a SLB for that address */
for (i = 0; i < ARRAY_SIZE(addrs); i++) {
if (__slb_present(slbs, nr_slbs, addrs[i]))
continue;
__spu_kernel_slb(addrs[i], &slbs[nr_slbs]);
nr_slbs++;
}
spin_lock_irq(&spu->register_lock);
/* Add the set of SLBs */
for (i = 0; i < nr_slbs; i++)
spu_load_slb(spu, i, &slbs[i]);
spin_unlock_irq(&spu->register_lock);
}
EXPORT_SYMBOL_GPL(spu_setup_kernel_slbs);
static irqreturn_t
spu_irq_class_0(int irq, void *data)
{
struct spu *spu;
unsigned long stat, mask;
spu = data;
spin_lock(&spu->register_lock);
mask = spu_int_mask_get(spu, 0);
stat = spu_int_stat_get(spu, 0) & mask;
spu->class_0_pending |= stat;
spu->class_0_dar = spu_mfc_dar_get(spu);
spu->stop_callback(spu, 0);
spu->class_0_pending = 0;
spu->class_0_dar = 0;
spu_int_stat_clear(spu, 0, stat);
spin_unlock(&spu->register_lock);
return IRQ_HANDLED;
}
static irqreturn_t
spu_irq_class_1(int irq, void *data)
{
struct spu *spu;
unsigned long stat, mask, dar, dsisr;
spu = data;
/* atomically read & clear class1 status. */
spin_lock(&spu->register_lock);
mask = spu_int_mask_get(spu, 1);
stat = spu_int_stat_get(spu, 1) & mask;
dar = spu_mfc_dar_get(spu);
dsisr = spu_mfc_dsisr_get(spu);
if (stat & CLASS1_STORAGE_FAULT_INTR)
spu_mfc_dsisr_set(spu, 0ul);
spu_int_stat_clear(spu, 1, stat);
pr_debug("%s: %lx %lx %lx %lx\n", __func__, mask, stat,
dar, dsisr);
if (stat & CLASS1_SEGMENT_FAULT_INTR)
__spu_trap_data_seg(spu, dar);
if (stat & CLASS1_STORAGE_FAULT_INTR)
__spu_trap_data_map(spu, dar, dsisr);
spu->class_1_dsisr = 0;
spu->class_1_dar = 0;
spin_unlock(&spu->register_lock);
return stat ? IRQ_HANDLED : IRQ_NONE;
}
static irqreturn_t
spu_irq_class_2(int irq, void *data)
{
struct spu *spu;
unsigned long stat;
unsigned long mask;
const int mailbox_intrs =
CLASS2_MAILBOX_THRESHOLD_INTR | CLASS2_MAILBOX_INTR;
spu = data;
spin_lock(&spu->register_lock);
stat = spu_int_stat_get(spu, 2);
mask = spu_int_mask_get(spu, 2);
/* ignore interrupts we're not waiting for */
stat &= mask;
/* mailbox interrupts are level triggered. mask them now before
* acknowledging */
if (stat & mailbox_intrs)
spu_int_mask_and(spu, 2, ~(stat & mailbox_intrs));
/* acknowledge all interrupts before the callbacks */
spu_int_stat_clear(spu, 2, stat);
pr_debug("class 2 interrupt %d, %lx, %lx\n", irq, stat, mask);
if (stat & CLASS2_MAILBOX_INTR)
spu->ibox_callback(spu);
if (stat & CLASS2_SPU_STOP_INTR)
spu->stop_callback(spu, 2);
if (stat & CLASS2_SPU_HALT_INTR)
spu->stop_callback(spu, 2);
if (stat & CLASS2_SPU_DMA_TAG_GROUP_COMPLETE_INTR)
spu->mfc_callback(spu);
if (stat & CLASS2_MAILBOX_THRESHOLD_INTR)
spu->wbox_callback(spu);
spu->stats.class2_intr++;
spin_unlock(&spu->register_lock);
return stat ? IRQ_HANDLED : IRQ_NONE;
}
static int __init spu_request_irqs(struct spu *spu)
{
int ret = 0;
if (spu->irqs[0]) {
snprintf(spu->irq_c0, sizeof (spu->irq_c0), "spe%02d.0",
spu->number);
ret = request_irq(spu->irqs[0], spu_irq_class_0,
0, spu->irq_c0, spu);
if (ret)
goto bail0;
}
if (spu->irqs[1]) {
snprintf(spu->irq_c1, sizeof (spu->irq_c1), "spe%02d.1",
spu->number);
ret = request_irq(spu->irqs[1], spu_irq_class_1,
0, spu->irq_c1, spu);
if (ret)
goto bail1;
}
if (spu->irqs[2]) {
snprintf(spu->irq_c2, sizeof (spu->irq_c2), "spe%02d.2",
spu->number);
ret = request_irq(spu->irqs[2], spu_irq_class_2,
0, spu->irq_c2, spu);
if (ret)
goto bail2;
}
return 0;
bail2:
if (spu->irqs[1])
free_irq(spu->irqs[1], spu);
bail1:
if (spu->irqs[0])
free_irq(spu->irqs[0], spu);
bail0:
return ret;
}
static void spu_free_irqs(struct spu *spu)
{
if (spu->irqs[0])
free_irq(spu->irqs[0], spu);
if (spu->irqs[1])
free_irq(spu->irqs[1], spu);
if (spu->irqs[2])
free_irq(spu->irqs[2], spu);
}
void spu_init_channels(struct spu *spu)
{
static const struct {
unsigned channel;
unsigned count;
} zero_list[] = {
{ 0x00, 1, }, { 0x01, 1, }, { 0x03, 1, }, { 0x04, 1, },
{ 0x18, 1, }, { 0x19, 1, }, { 0x1b, 1, }, { 0x1d, 1, },
}, count_list[] = {
{ 0x00, 0, }, { 0x03, 0, }, { 0x04, 0, }, { 0x15, 16, },
{ 0x17, 1, }, { 0x18, 0, }, { 0x19, 0, }, { 0x1b, 0, },
{ 0x1c, 1, }, { 0x1d, 0, }, { 0x1e, 1, },
};
struct spu_priv2 __iomem *priv2;
int i;
priv2 = spu->priv2;
/* initialize all channel data to zero */
for (i = 0; i < ARRAY_SIZE(zero_list); i++) {
int count;
out_be64(&priv2->spu_chnlcntptr_RW, zero_list[i].channel);
for (count = 0; count < zero_list[i].count; count++)
out_be64(&priv2->spu_chnldata_RW, 0);
}
/* initialize channel counts to meaningful values */
for (i = 0; i < ARRAY_SIZE(count_list); i++) {
out_be64(&priv2->spu_chnlcntptr_RW, count_list[i].channel);
out_be64(&priv2->spu_chnlcnt_RW, count_list[i].count);
}
}
EXPORT_SYMBOL_GPL(spu_init_channels);
static struct bus_type spu_subsys = {
.name = "spu",
.dev_name = "spu",
};
int spu_add_dev_attr(struct device_attribute *attr)
{
struct spu *spu;
mutex_lock(&spu_full_list_mutex);
list_for_each_entry(spu, &spu_full_list, full_list)
device_create_file(&spu->dev, attr);
mutex_unlock(&spu_full_list_mutex);
return 0;
}
EXPORT_SYMBOL_GPL(spu_add_dev_attr);
int spu_add_dev_attr_group(const struct attribute_group *attrs)
{
struct spu *spu;
int rc = 0;
mutex_lock(&spu_full_list_mutex);
list_for_each_entry(spu, &spu_full_list, full_list) {
rc = sysfs_create_group(&spu->dev.kobj, attrs);
/* we're in trouble here, but try unwinding anyway */
if (rc) {
printk(KERN_ERR "%s: can't create sysfs group '%s'\n",
__func__, attrs->name);
list_for_each_entry_continue_reverse(spu,
&spu_full_list, full_list)
sysfs_remove_group(&spu->dev.kobj, attrs);
break;
}
}
mutex_unlock(&spu_full_list_mutex);
return rc;
}
EXPORT_SYMBOL_GPL(spu_add_dev_attr_group);
void spu_remove_dev_attr(struct device_attribute *attr)
{
struct spu *spu;
mutex_lock(&spu_full_list_mutex);
list_for_each_entry(spu, &spu_full_list, full_list)
device_remove_file(&spu->dev, attr);
mutex_unlock(&spu_full_list_mutex);
}
EXPORT_SYMBOL_GPL(spu_remove_dev_attr);
void spu_remove_dev_attr_group(const struct attribute_group *attrs)
{
struct spu *spu;
mutex_lock(&spu_full_list_mutex);
list_for_each_entry(spu, &spu_full_list, full_list)
sysfs_remove_group(&spu->dev.kobj, attrs);
mutex_unlock(&spu_full_list_mutex);
}
EXPORT_SYMBOL_GPL(spu_remove_dev_attr_group);
static int __init spu_create_dev(struct spu *spu)
{
int ret;
spu->dev.id = spu->number;
spu->dev.bus = &spu_subsys;
ret = device_register(&spu->dev);
if (ret) {
printk(KERN_ERR "Can't register SPU %d with sysfs\n",
spu->number);
return ret;
}
sysfs_add_device_to_node(&spu->dev, spu->node);
return 0;
}
static int __init create_spu(void *data)
{
struct spu *spu;
int ret;
static int number;
unsigned long flags;
ret = -ENOMEM;
spu = kzalloc(sizeof (*spu), GFP_KERNEL);
if (!spu)
goto out;
spu->alloc_state = SPU_FREE;
spin_lock_init(&spu->register_lock);
spin_lock(&spu_lock);
spu->number = number++;
spin_unlock(&spu_lock);
ret = spu_create_spu(spu, data);
if (ret)
goto out_free;
spu_mfc_sdr_setup(spu);
spu_mfc_sr1_set(spu, 0x33);
ret = spu_request_irqs(spu);
if (ret)
goto out_destroy;
ret = spu_create_dev(spu);
if (ret)
goto out_free_irqs;
mutex_lock(&cbe_spu_info[spu->node].list_mutex);
list_add(&spu->cbe_list, &cbe_spu_info[spu->node].spus);
cbe_spu_info[spu->node].n_spus++;
mutex_unlock(&cbe_spu_info[spu->node].list_mutex);
mutex_lock(&spu_full_list_mutex);
spin_lock_irqsave(&spu_full_list_lock, flags);
list_add(&spu->full_list, &spu_full_list);
spin_unlock_irqrestore(&spu_full_list_lock, flags);
mutex_unlock(&spu_full_list_mutex);
spu->stats.util_state = SPU_UTIL_IDLE_LOADED;
spu->stats.tstamp = ktime_get_ns();
INIT_LIST_HEAD(&spu->aff_list);
goto out;
out_free_irqs:
spu_free_irqs(spu);
out_destroy:
spu_destroy_spu(spu);
out_free:
kfree(spu);
out:
return ret;
}
static const char *spu_state_names[] = {
"user", "system", "iowait", "idle"
};
static unsigned long long spu_acct_time(struct spu *spu,
enum spu_utilization_state state)
{
unsigned long long time = spu->stats.times[state];
/*
* If the spu is idle or the context is stopped, utilization
* statistics are not updated. Apply the time delta from the
* last recorded state of the spu.
*/
if (spu->stats.util_state == state)
time += ktime_get_ns() - spu->stats.tstamp;
return time / NSEC_PER_MSEC;
}
static ssize_t spu_stat_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct spu *spu = container_of(dev, struct spu, dev);
return sprintf(buf, "%s %llu %llu %llu %llu "
"%llu %llu %llu %llu %llu %llu %llu %llu\n",
spu_state_names[spu->stats.util_state],
spu_acct_time(spu, SPU_UTIL_USER),
spu_acct_time(spu, SPU_UTIL_SYSTEM),
spu_acct_time(spu, SPU_UTIL_IOWAIT),
spu_acct_time(spu, SPU_UTIL_IDLE_LOADED),
spu->stats.vol_ctx_switch,
spu->stats.invol_ctx_switch,
spu->stats.slb_flt,
spu->stats.hash_flt,
spu->stats.min_flt,
spu->stats.maj_flt,
spu->stats.class2_intr,
spu->stats.libassist);
}
static DEVICE_ATTR(stat, 0444, spu_stat_show, NULL);
#ifdef CONFIG_KEXEC_CORE
struct crash_spu_info {
struct spu *spu;
u32 saved_spu_runcntl_RW;
u32 saved_spu_status_R;
u32 saved_spu_npc_RW;
u64 saved_mfc_sr1_RW;
u64 saved_mfc_dar;
u64 saved_mfc_dsisr;
};
#define CRASH_NUM_SPUS 16 /* Enough for current hardware */
static struct crash_spu_info crash_spu_info[CRASH_NUM_SPUS];
static void crash_kexec_stop_spus(void)
{
struct spu *spu;
int i;
u64 tmp;
for (i = 0; i < CRASH_NUM_SPUS; i++) {
if (!crash_spu_info[i].spu)
continue;
spu = crash_spu_info[i].spu;
crash_spu_info[i].saved_spu_runcntl_RW =
in_be32(&spu->problem->spu_runcntl_RW);
crash_spu_info[i].saved_spu_status_R =
in_be32(&spu->problem->spu_status_R);
crash_spu_info[i].saved_spu_npc_RW =
in_be32(&spu->problem->spu_npc_RW);
crash_spu_info[i].saved_mfc_dar = spu_mfc_dar_get(spu);
crash_spu_info[i].saved_mfc_dsisr = spu_mfc_dsisr_get(spu);
tmp = spu_mfc_sr1_get(spu);
crash_spu_info[i].saved_mfc_sr1_RW = tmp;
tmp &= ~MFC_STATE1_MASTER_RUN_CONTROL_MASK;
spu_mfc_sr1_set(spu, tmp);
__delay(200);
}
}
static void __init crash_register_spus(struct list_head *list)
{
struct spu *spu;
int ret;
list_for_each_entry(spu, list, full_list) {
if (WARN_ON(spu->number >= CRASH_NUM_SPUS))
continue;
crash_spu_info[spu->number].spu = spu;
}
ret = crash_shutdown_register(&crash_kexec_stop_spus);
if (ret)
printk(KERN_ERR "Could not register SPU crash handler");
}
#else
static inline void crash_register_spus(struct list_head *list)
{
}
#endif
static void spu_shutdown(void)
{
struct spu *spu;
mutex_lock(&spu_full_list_mutex);
list_for_each_entry(spu, &spu_full_list, full_list) {
spu_free_irqs(spu);
spu_destroy_spu(spu);
}
mutex_unlock(&spu_full_list_mutex);
}
static struct syscore_ops spu_syscore_ops = {
.shutdown = spu_shutdown,
};
static int __init init_spu_base(void)
{
int i, ret = 0;
for (i = 0; i < MAX_NUMNODES; i++) {
mutex_init(&cbe_spu_info[i].list_mutex);
INIT_LIST_HEAD(&cbe_spu_info[i].spus);
}
if (!spu_management_ops)
goto out;
/* create system subsystem for spus */
ret = subsys_system_register(&spu_subsys, NULL);
if (ret)
goto out;
ret = spu_enumerate_spus(create_spu);
if (ret < 0) {
printk(KERN_WARNING "%s: Error initializing spus\n",
__func__);
goto out_unregister_subsys;
}
if (ret > 0)
fb_append_extra_logo(&logo_spe_clut224, ret);
mutex_lock(&spu_full_list_mutex);
xmon_register_spus(&spu_full_list);
crash_register_spus(&spu_full_list);
mutex_unlock(&spu_full_list_mutex);
spu_add_dev_attr(&dev_attr_stat);
register_syscore_ops(&spu_syscore_ops);
spu_init_affinity();
return 0;
out_unregister_subsys:
bus_unregister(&spu_subsys);
out:
return ret;
}
device_initcall(init_spu_base);
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linux