// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright 2016,2017 IBM Corporation.
*/
#define pr_fmt(fmt) "xive: " fmt
#include <linux/types.h>
#include <linux/irq.h>
#include <linux/smp.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/cpumask.h>
#include <linux/mm.h>
#include <linux/delay.h>
#include <linux/libfdt.h>
#include <asm/prom.h>
#include <asm/io.h>
#include <asm/smp.h>
#include <asm/irq.h>
#include <asm/errno.h>
#include <asm/xive.h>
#include <asm/xive-regs.h>
#include <asm/hvcall.h>
#include "xive-internal.h"
static u32 xive_queue_shift;
struct xive_irq_bitmap {
unsigned long *bitmap;
unsigned int base;
unsigned int count;
spinlock_t lock;
struct list_head list;
};
static LIST_HEAD(xive_irq_bitmaps);
static int xive_irq_bitmap_add(int base, int count)
{
struct xive_irq_bitmap *xibm;
xibm = kzalloc(sizeof(*xibm), GFP_KERNEL);
if (!xibm)
return -ENOMEM;
spin_lock_init(&xibm->lock);
xibm->base = base;
xibm->count = count;
xibm->bitmap = kzalloc(xibm->count, GFP_KERNEL);
if (!xibm->bitmap) {
kfree(xibm);
return -ENOMEM;
}
list_add(&xibm->list, &xive_irq_bitmaps);
pr_info("Using IRQ range [%x-%x]", xibm->base,
xibm->base + xibm->count - 1);
return 0;
}
static int __xive_irq_bitmap_alloc(struct xive_irq_bitmap *xibm)
{
int irq;
irq = find_first_zero_bit(xibm->bitmap, xibm->count);
if (irq != xibm->count) {
set_bit(irq, xibm->bitmap);
irq += xibm->base;
} else {
irq = -ENOMEM;
}
return irq;
}
static int xive_irq_bitmap_alloc(void)
{
struct xive_irq_bitmap *xibm;
unsigned long flags;
int irq = -ENOENT;
list_for_each_entry(xibm, &xive_irq_bitmaps, list) {
spin_lock_irqsave(&xibm->lock, flags);
irq = __xive_irq_bitmap_alloc(xibm);
spin_unlock_irqrestore(&xibm->lock, flags);
if (irq >= 0)
break;
}
return irq;
}
static void xive_irq_bitmap_free(int irq)
{
unsigned long flags;
struct xive_irq_bitmap *xibm;
list_for_each_entry(xibm, &xive_irq_bitmaps, list) {
if ((irq >= xibm->base) && (irq < xibm->base + xibm->count)) {
spin_lock_irqsave(&xibm->lock, flags);
clear_bit(irq - xibm->base, xibm->bitmap);
spin_unlock_irqrestore(&xibm->lock, flags);
break;
}
}
}
/* Based on the similar routines in RTAS */
static unsigned int plpar_busy_delay_time(long rc)
{
unsigned int ms = 0;
if (H_IS_LONG_BUSY(rc)) {
ms = get_longbusy_msecs(rc);
} else if (rc == H_BUSY) {
ms = 10; /* seems appropriate for XIVE hcalls */
}
return ms;
}
static unsigned int plpar_busy_delay(int rc)
{
unsigned int ms;
ms = plpar_busy_delay_time(rc);
if (ms)
mdelay(ms);
return ms;
}
/*
* Note: this call has a partition wide scope and can take a while to
* complete. If it returns H_LONG_BUSY_* it should be retried
* periodically.
*/
static long plpar_int_reset(unsigned long flags)
{
long rc;
do {
rc = plpar_hcall_norets(H_INT_RESET, flags);
} while (plpar_busy_delay(rc));
if (rc)
pr_err("H_INT_RESET failed %ld\n", rc);
return rc;
}
static long plpar_int_get_source_info(unsigned long flags,
unsigned long lisn,
unsigned long *src_flags,
unsigned long *eoi_page,
unsigned long *trig_page,
unsigned long *esb_shift)
{
unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
long rc;
do {
rc = plpar_hcall(H_INT_GET_SOURCE_INFO, retbuf, flags, lisn);
} while (plpar_busy_delay(rc));
if (rc) {
pr_err("H_INT_GET_SOURCE_INFO lisn=%ld failed %ld\n", lisn, rc);
return rc;
}
*src_flags = retbuf[0];
*eoi_page = retbuf[1];
*trig_page = retbuf[2];
*esb_shift = retbuf[3];
pr_devel("H_INT_GET_SOURCE_INFO flags=%lx eoi=%lx trig=%lx shift=%lx\n",
retbuf[0], retbuf[1], retbuf[2], retbuf[3]);
return 0;
}
#define XIVE_SRC_SET_EISN (1ull << (63 - 62))
#define XIVE_SRC_MASK (1ull << (63 - 63)) /* unused */
static long plpar_int_set_source_config(unsigned long flags,
unsigned long lisn,
unsigned long target,
unsigned long prio,
unsigned long sw_irq)
{
long rc;
pr_devel("H_INT_SET_SOURCE_CONFIG flags=%lx lisn=%lx target=%lx prio=%lx sw_irq=%lx\n",
flags, lisn, target, prio, sw_irq);
do {
rc = plpar_hcall_norets(H_INT_SET_SOURCE_CONFIG, flags, lisn,
target, prio, sw_irq);
} while (plpar_busy_delay(rc));
if (rc) {
pr_err("H_INT_SET_SOURCE_CONFIG lisn=%ld target=%lx prio=%lx failed %ld\n",
lisn, target, prio, rc);
return rc;
}
return 0;
}
static long plpar_int_get_source_config(unsigned long flags,
unsigned long lisn,
unsigned long *target,
unsigned long *prio,
unsigned long *sw_irq)
{
unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
long rc;
pr_devel("H_INT_GET_SOURCE_CONFIG flags=%lx lisn=%lx\n", flags, lisn);
do {
rc = plpar_hcall(H_INT_GET_SOURCE_CONFIG, retbuf, flags, lisn,
target, prio, sw_irq);
} while (plpar_busy_delay(rc));
if (rc) {
pr_err("H_INT_GET_SOURCE_CONFIG lisn=%ld failed %ld\n",
lisn, rc);
return rc;
}
*target = retbuf[0];
*prio = retbuf[1];
*sw_irq = retbuf[2];
pr_devel("H_INT_GET_SOURCE_CONFIG target=%lx prio=%lx sw_irq=%lx\n",
retbuf[0], retbuf[1], retbuf[2]);
return 0;
}
static long plpar_int_get_queue_info(unsigned long flags,
unsigned long target,
unsigned long priority,
unsigned long *esn_page,
unsigned long *esn_size)
{
unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
long rc;
do {
rc = plpar_hcall(H_INT_GET_QUEUE_INFO, retbuf, flags, target,
priority);
} while (plpar_busy_delay(rc));
if (rc) {
pr_err("H_INT_GET_QUEUE_INFO cpu=%ld prio=%ld failed %ld\n",
target, priority, rc);
return rc;
}
*esn_page = retbuf[0];
*esn_size = retbuf[1];
pr_devel("H_INT_GET_QUEUE_INFO page=%lx size=%lx\n",
retbuf[0], retbuf[1]);
return 0;
}
#define XIVE_EQ_ALWAYS_NOTIFY (1ull << (63 - 63))
static long plpar_int_set_queue_config(unsigned long flags,
unsigned long target,
unsigned long priority,
unsigned long qpage,
unsigned long qsize)
{
long rc;
pr_devel("H_INT_SET_QUEUE_CONFIG flags=%lx target=%lx priority=%lx qpage=%lx qsize=%lx\n",
flags, target, priority, qpage, qsize);
do {
rc = plpar_hcall_norets(H_INT_SET_QUEUE_CONFIG, flags, target,
priority, qpage, qsize);
} while (plpar_busy_delay(rc));
if (rc) {
pr_err("H_INT_SET_QUEUE_CONFIG cpu=%ld prio=%ld qpage=%lx returned %ld\n",
target, priority, qpage, rc);
return rc;
}
return 0;
}
static long plpar_int_sync(unsigned long flags, unsigned long lisn)
{
long rc;
do {
rc = plpar_hcall_norets(H_INT_SYNC, flags, lisn);
} while (plpar_busy_delay(rc));
if (rc) {
pr_err("H_INT_SYNC lisn=%ld returned %ld\n", lisn, rc);
return rc;
}
return 0;
}
#define XIVE_ESB_FLAG_STORE (1ull << (63 - 63))
static long plpar_int_esb(unsigned long flags,
unsigned long lisn,
unsigned long offset,
unsigned long in_data,
unsigned long *out_data)
{
unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
long rc;
pr_devel("H_INT_ESB flags=%lx lisn=%lx offset=%lx in=%lx\n",
flags, lisn, offset, in_data);
do {
rc = plpar_hcall(H_INT_ESB, retbuf, flags, lisn, offset,
in_data);
} while (plpar_busy_delay(rc));
if (rc) {
pr_err("H_INT_ESB lisn=%ld offset=%ld returned %ld\n",
lisn, offset, rc);
return rc;
}
*out_data = retbuf[0];
return 0;
}
static u64 xive_spapr_esb_rw(u32 lisn, u32 offset, u64 data, bool write)
{
unsigned long read_data;
long rc;
rc = plpar_int_esb(write ? XIVE_ESB_FLAG_STORE : 0,
lisn, offset, data, &read_data);
if (rc)
return -1;
return write ? 0 : read_data;
}
#define XIVE_SRC_H_INT_ESB (1ull << (63 - 60))
#define XIVE_SRC_LSI (1ull << (63 - 61))
#define XIVE_SRC_TRIGGER (1ull << (63 - 62))
#define XIVE_SRC_STORE_EOI (1ull << (63 - 63))
static int xive_spapr_populate_irq_data(u32 hw_irq, struct xive_irq_data *data)
{
long rc;
unsigned long flags;
unsigned long eoi_page;
unsigned long trig_page;
unsigned long esb_shift;
memset(data, 0, sizeof(*data));
rc = plpar_int_get_source_info(0, hw_irq, &flags, &eoi_page, &trig_page,
&esb_shift);
if (rc)
return -EINVAL;
if (flags & XIVE_SRC_H_INT_ESB)
data->flags |= XIVE_IRQ_FLAG_H_INT_ESB;
if (flags & XIVE_SRC_STORE_EOI)
data->flags |= XIVE_IRQ_FLAG_STORE_EOI;
if (flags & XIVE_SRC_LSI)
data->flags |= XIVE_IRQ_FLAG_LSI;
data->eoi_page = eoi_page;
data->esb_shift = esb_shift;
data->trig_page = trig_page;
data->hw_irq = hw_irq;
/*
* No chip-id for the sPAPR backend. This has an impact how we
* pick a target. See xive_pick_irq_target().
*/
data->src_chip = XIVE_INVALID_CHIP_ID;
/*
* When the H_INT_ESB flag is set, the H_INT_ESB hcall should
* be used for interrupt management. Skip the remapping of the
* ESB pages which are not available.
*/
if (data->flags & XIVE_IRQ_FLAG_H_INT_ESB)
return 0;
data->eoi_mmio = ioremap(data->eoi_page, 1u << data->esb_shift);
if (!data->eoi_mmio) {
pr_err("Failed to map EOI page for irq 0x%x\n", hw_irq);
return -ENOMEM;
}
/* Full function page supports trigger */
if (flags & XIVE_SRC_TRIGGER) {
data->trig_mmio = data->eoi_mmio;
return 0;
}
data->trig_mmio = ioremap(data->trig_page, 1u << data->esb_shift);
if (!data->trig_mmio) {
pr_err("Failed to map trigger page for irq 0x%x\n", hw_irq);
return -ENOMEM;
}
return 0;
}
static int xive_spapr_configure_irq(u32 hw_irq, u32 target, u8 prio, u32 sw_irq)
{
long rc;
rc = plpar_int_set_source_config(XIVE_SRC_SET_EISN, hw_irq, target,
prio, sw_irq);
return rc == 0 ? 0 : -ENXIO;
}
static int xive_spapr_get_irq_config(u32 hw_irq, u32 *target, u8 *prio,
u32 *sw_irq)
{
long rc;
unsigned long h_target;
unsigned long h_prio;
unsigned long h_sw_irq;
rc = plpar_int_get_source_config(0, hw_irq, &h_target, &h_prio,
&h_sw_irq);
*target = h_target;
*prio = h_prio;
*sw_irq = h_sw_irq;
return rc == 0 ? 0 : -ENXIO;
}
/* This can be called multiple time to change a queue configuration */
static int xive_spapr_configure_queue(u32 target, struct xive_q *q, u8 prio,
__be32 *qpage, u32 order)
{
s64 rc = 0;
unsigned long esn_page;
unsigned long esn_size;
u64 flags, qpage_phys;
/* If there's an actual queue page, clean it */
if (order) {
if (WARN_ON(!qpage))
return -EINVAL;
qpage_phys = __pa(qpage);
} else {
qpage_phys = 0;
}
/* Initialize the rest of the fields */
q->msk = order ? ((1u << (order - 2)) - 1) : 0;
q->idx = 0;
q->toggle = 0;
rc = plpar_int_get_queue_info(0, target, prio, &esn_page, &esn_size);
if (rc) {
pr_err("Error %lld getting queue info CPU %d prio %d\n", rc,
target, prio);
rc = -EIO;
goto fail;
}
/* TODO: add support for the notification page */
q->eoi_phys = esn_page;
/* Default is to always notify */
flags = XIVE_EQ_ALWAYS_NOTIFY;
/* Configure and enable the queue in HW */
rc = plpar_int_set_queue_config(flags, target, prio, qpage_phys, order);
if (rc) {
pr_err("Error %lld setting queue for CPU %d prio %d\n", rc,
target, prio);
rc = -EIO;
} else {
q->qpage = qpage;
}
fail:
return rc;
}
static int xive_spapr_setup_queue(unsigned int cpu, struct xive_cpu *xc,
u8 prio)
{
struct xive_q *q = &xc->queue[prio];
__be32 *qpage;
qpage = xive_queue_page_alloc(cpu, xive_queue_shift);
if (IS_ERR(qpage))
return PTR_ERR(qpage);
return xive_spapr_configure_queue(get_hard_smp_processor_id(cpu),
q, prio, qpage, xive_queue_shift);
}
static void xive_spapr_cleanup_queue(unsigned int cpu, struct xive_cpu *xc,
u8 prio)
{
struct xive_q *q = &xc->queue[prio];
unsigned int alloc_order;
long rc;
int hw_cpu = get_hard_smp_processor_id(cpu);
rc = plpar_int_set_queue_config(0, hw_cpu, prio, 0, 0);
if (rc)
pr_err("Error %ld setting queue for CPU %d prio %d\n", rc,
hw_cpu, prio);
alloc_order = xive_alloc_order(xive_queue_shift);
free_pages((unsigned long)q->qpage, alloc_order);
q->qpage = NULL;
}
static bool xive_spapr_match(struct device_node *node)
{
/* Ignore cascaded controllers for the moment */
return 1;
}
#ifdef CONFIG_SMP
static int xive_spapr_get_ipi(unsigned int cpu, struct xive_cpu *xc)
{
int irq = xive_irq_bitmap_alloc();
if (irq < 0) {
pr_err("Failed to allocate IPI on CPU %d\n", cpu);
return -ENXIO;
}
xc->hw_ipi = irq;
return 0;
}
static void xive_spapr_put_ipi(unsigned int cpu, struct xive_cpu *xc)
{
if (!xc->hw_ipi)
return;
xive_irq_bitmap_free(xc->hw_ipi);
xc->hw_ipi = 0;
}
#endif /* CONFIG_SMP */
static void xive_spapr_shutdown(void)
{
plpar_int_reset(0);
}
/*
* Perform an "ack" cycle on the current thread. Grab the pending
* active priorities and update the CPPR to the most favored one.
*/
static void xive_spapr_update_pending(struct xive_cpu *xc)
{
u8 nsr, cppr;
u16 ack;
/*
* Perform the "Acknowledge O/S to Register" cycle.
*
* Let's speedup the access to the TIMA using the raw I/O
* accessor as we don't need the synchronisation routine of
* the higher level ones
*/
ack = be16_to_cpu(__raw_readw(xive_tima + TM_SPC_ACK_OS_REG));
/* Synchronize subsequent queue accesses */
mb();
/*
* Grab the CPPR and the "NSR" field which indicates the source
* of the interrupt (if any)
*/
cppr = ack & 0xff;
nsr = ack >> 8;
if (nsr & TM_QW1_NSR_EO) {
if (cppr == 0xff)
return;
/* Mark the priority pending */
xc->pending_prio |= 1 << cppr;
/*
* A new interrupt should never have a CPPR less favored
* than our current one.
*/
if (cppr >= xc->cppr)
pr_err("CPU %d odd ack CPPR, got %d at %d\n",
smp_processor_id(), cppr, xc->cppr);
/* Update our idea of what the CPPR is */
xc->cppr = cppr;
}
}
static void xive_spapr_eoi(u32 hw_irq)
{
/* Not used */;
}
static void xive_spapr_setup_cpu(unsigned int cpu, struct xive_cpu *xc)
{
/* Only some debug on the TIMA settings */
pr_debug("(HW value: %08x %08x %08x)\n",
in_be32(xive_tima + TM_QW1_OS + TM_WORD0),
in_be32(xive_tima + TM_QW1_OS + TM_WORD1),
in_be32(xive_tima + TM_QW1_OS + TM_WORD2));
}
static void xive_spapr_teardown_cpu(unsigned int cpu, struct xive_cpu *xc)
{
/* Nothing to do */;
}
static void xive_spapr_sync_source(u32 hw_irq)
{
/* Specs are unclear on what this is doing */
plpar_int_sync(0, hw_irq);
}
static const struct xive_ops xive_spapr_ops = {
.populate_irq_data = xive_spapr_populate_irq_data,
.configure_irq = xive_spapr_configure_irq,
.get_irq_config = xive_spapr_get_irq_config,
.setup_queue = xive_spapr_setup_queue,
.cleanup_queue = xive_spapr_cleanup_queue,
.match = xive_spapr_match,
.shutdown = xive_spapr_shutdown,
.update_pending = xive_spapr_update_pending,
.eoi = xive_spapr_eoi,
.setup_cpu = xive_spapr_setup_cpu,
.teardown_cpu = xive_spapr_teardown_cpu,
.sync_source = xive_spapr_sync_source,
.esb_rw = xive_spapr_esb_rw,
#ifdef CONFIG_SMP
.get_ipi = xive_spapr_get_ipi,
.put_ipi = xive_spapr_put_ipi,
#endif /* CONFIG_SMP */
.name = "spapr",
};
/*
* get max priority from "/ibm,plat-res-int-priorities"
*/
static bool xive_get_max_prio(u8 *max_prio)
{
struct device_node *rootdn;
const __be32 *reg;
u32 len;
int prio, found;
rootdn = of_find_node_by_path("/");
if (!rootdn) {
pr_err("not root node found !\n");
return false;
}
reg = of_get_property(rootdn, "ibm,plat-res-int-priorities", &len);
if (!reg) {
pr_err("Failed to read 'ibm,plat-res-int-priorities' property\n");
return false;
}
if (len % (2 * sizeof(u32)) != 0) {
pr_err("invalid 'ibm,plat-res-int-priorities' property\n");
return false;
}
/* HW supports priorities in the range [0-7] and 0xFF is a
* wildcard priority used to mask. We scan the ranges reserved
* by the hypervisor to find the lowest priority we can use.
*/
found = 0xFF;
for (prio = 0; prio < 8; prio++) {
int reserved = 0;
int i;
for (i = 0; i < len / (2 * sizeof(u32)); i++) {
int base = be32_to_cpu(reg[2 * i]);
int range = be32_to_cpu(reg[2 * i + 1]);
if (prio >= base && prio < base + range)
reserved++;
}
if (!reserved)
found = prio;
}
if (found == 0xFF) {
pr_err("no valid priority found in 'ibm,plat-res-int-priorities'\n");
return false;
}
*max_prio = found;
return true;
}
static const u8 *get_vec5_feature(unsigned int index)
{
unsigned long root, chosen;
int size;
const u8 *vec5;
root = of_get_flat_dt_root();
chosen = of_get_flat_dt_subnode_by_name(root, "chosen");
if (chosen == -FDT_ERR_NOTFOUND)
return NULL;
vec5 = of_get_flat_dt_prop(chosen, "ibm,architecture-vec-5", &size);
if (!vec5)
return NULL;
if (size <= index)
return NULL;
return vec5 + index;
}
static bool xive_spapr_disabled(void)
{
const u8 *vec5_xive;
vec5_xive = get_vec5_feature(OV5_INDX(OV5_XIVE_SUPPORT));
if (vec5_xive) {
u8 val;
val = *vec5_xive & OV5_FEAT(OV5_XIVE_SUPPORT);
switch (val) {
case OV5_FEAT(OV5_XIVE_EITHER):
case OV5_FEAT(OV5_XIVE_LEGACY):
break;
case OV5_FEAT(OV5_XIVE_EXPLOIT):
/* Hypervisor only supports XIVE */
if (xive_cmdline_disabled)
pr_warn("WARNING: Ignoring cmdline option xive=off\n");
return false;
default:
pr_warn("%s: Unknown xive support option: 0x%x\n",
__func__, val);
break;
}
}
return xive_cmdline_disabled;
}
bool __init xive_spapr_init(void)
{
struct device_node *np;
struct resource r;
void __iomem *tima;
struct property *prop;
u8 max_prio;
u32 val;
u32 len;
const __be32 *reg;
int i;
if (xive_spapr_disabled())
return false;
pr_devel("%s()\n", __func__);
np = of_find_compatible_node(NULL, NULL, "ibm,power-ivpe");
if (!np) {
pr_devel("not found !\n");
return false;
}
pr_devel("Found %s\n", np->full_name);
/* Resource 1 is the OS ring TIMA */
if (of_address_to_resource(np, 1, &r)) {
pr_err("Failed to get thread mgmnt area resource\n");
return false;
}
tima = ioremap(r.start, resource_size(&r));
if (!tima) {
pr_err("Failed to map thread mgmnt area\n");
return false;
}
if (!xive_get_max_prio(&max_prio))
return false;
/* Feed the IRQ number allocator with the ranges given in the DT */
reg = of_get_property(np, "ibm,xive-lisn-ranges", &len);
if (!reg) {
pr_err("Failed to read 'ibm,xive-lisn-ranges' property\n");
return false;
}
if (len % (2 * sizeof(u32)) != 0) {
pr_err("invalid 'ibm,xive-lisn-ranges' property\n");
return false;
}
for (i = 0; i < len / (2 * sizeof(u32)); i++, reg += 2)
xive_irq_bitmap_add(be32_to_cpu(reg[0]),
be32_to_cpu(reg[1]));
/* Iterate the EQ sizes and pick one */
of_property_for_each_u32(np, "ibm,xive-eq-sizes", prop, reg, val) {
xive_queue_shift = val;
if (val == PAGE_SHIFT)
break;
}
/* Initialize XIVE core with our backend */
if (!xive_core_init(&xive_spapr_ops, tima, TM_QW1_OS, max_prio))
return false;
pr_info("Using %dkB queues\n", 1 << (xive_queue_shift - 10));
return true;
}