blob: 4dce2edd86ea0f9a4d223f2f6047e8a7db03d42e [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-only
/*
* Thunderbolt driver - NHI driver
*
* The NHI (native host interface) is the pci device that allows us to send and
* receive frames from the thunderbolt bus.
*
* Copyright (c) 2014 Andreas Noever <andreas.noever@gmail.com>
* Copyright (C) 2018, Intel Corporation
*/
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/pci.h>
#include <linux/dma-mapping.h>
#include <linux/interrupt.h>
#include <linux/iommu.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/property.h>
#include <linux/string_helpers.h>
#include "nhi.h"
#include "nhi_regs.h"
#include "tb.h"
#define RING_TYPE(ring) ((ring)->is_tx ? "TX ring" : "RX ring")
#define RING_FIRST_USABLE_HOPID 1
/*
* Used with QUIRK_E2E to specify an unused HopID the Rx credits are
* transferred.
*/
#define RING_E2E_RESERVED_HOPID RING_FIRST_USABLE_HOPID
/*
* Minimal number of vectors when we use MSI-X. Two for control channel
* Rx/Tx and the rest four are for cross domain DMA paths.
*/
#define MSIX_MIN_VECS 6
#define MSIX_MAX_VECS 16
#define NHI_MAILBOX_TIMEOUT 500 /* ms */
/* Host interface quirks */
#define QUIRK_AUTO_CLEAR_INT BIT(0)
#define QUIRK_E2E BIT(1)
static int ring_interrupt_index(struct tb_ring *ring)
{
int bit = ring->hop;
if (!ring->is_tx)
bit += ring->nhi->hop_count;
return bit;
}
/*
* ring_interrupt_active() - activate/deactivate interrupts for a single ring
*
* ring->nhi->lock must be held.
*/
static void ring_interrupt_active(struct tb_ring *ring, bool active)
{
int reg = REG_RING_INTERRUPT_BASE +
ring_interrupt_index(ring) / 32 * 4;
int bit = ring_interrupt_index(ring) & 31;
int mask = 1 << bit;
u32 old, new;
if (ring->irq > 0) {
u32 step, shift, ivr, misc;
void __iomem *ivr_base;
int index;
if (ring->is_tx)
index = ring->hop;
else
index = ring->hop + ring->nhi->hop_count;
if (ring->nhi->quirks & QUIRK_AUTO_CLEAR_INT) {
/*
* Ask the hardware to clear interrupt status
* bits automatically since we already know
* which interrupt was triggered.
*/
misc = ioread32(ring->nhi->iobase + REG_DMA_MISC);
if (!(misc & REG_DMA_MISC_INT_AUTO_CLEAR)) {
misc |= REG_DMA_MISC_INT_AUTO_CLEAR;
iowrite32(misc, ring->nhi->iobase + REG_DMA_MISC);
}
}
ivr_base = ring->nhi->iobase + REG_INT_VEC_ALLOC_BASE;
step = index / REG_INT_VEC_ALLOC_REGS * REG_INT_VEC_ALLOC_BITS;
shift = index % REG_INT_VEC_ALLOC_REGS * REG_INT_VEC_ALLOC_BITS;
ivr = ioread32(ivr_base + step);
ivr &= ~(REG_INT_VEC_ALLOC_MASK << shift);
if (active)
ivr |= ring->vector << shift;
iowrite32(ivr, ivr_base + step);
}
old = ioread32(ring->nhi->iobase + reg);
if (active)
new = old | mask;
else
new = old & ~mask;
dev_dbg(&ring->nhi->pdev->dev,
"%s interrupt at register %#x bit %d (%#x -> %#x)\n",
active ? "enabling" : "disabling", reg, bit, old, new);
if (new == old)
dev_WARN(&ring->nhi->pdev->dev,
"interrupt for %s %d is already %s\n",
RING_TYPE(ring), ring->hop,
active ? "enabled" : "disabled");
iowrite32(new, ring->nhi->iobase + reg);
}
/*
* nhi_disable_interrupts() - disable interrupts for all rings
*
* Use only during init and shutdown.
*/
static void nhi_disable_interrupts(struct tb_nhi *nhi)
{
int i = 0;
/* disable interrupts */
for (i = 0; i < RING_INTERRUPT_REG_COUNT(nhi); i++)
iowrite32(0, nhi->iobase + REG_RING_INTERRUPT_BASE + 4 * i);
/* clear interrupt status bits */
for (i = 0; i < RING_NOTIFY_REG_COUNT(nhi); i++)
ioread32(nhi->iobase + REG_RING_NOTIFY_BASE + 4 * i);
}
/* ring helper methods */
static void __iomem *ring_desc_base(struct tb_ring *ring)
{
void __iomem *io = ring->nhi->iobase;
io += ring->is_tx ? REG_TX_RING_BASE : REG_RX_RING_BASE;
io += ring->hop * 16;
return io;
}
static void __iomem *ring_options_base(struct tb_ring *ring)
{
void __iomem *io = ring->nhi->iobase;
io += ring->is_tx ? REG_TX_OPTIONS_BASE : REG_RX_OPTIONS_BASE;
io += ring->hop * 32;
return io;
}
static void ring_iowrite_cons(struct tb_ring *ring, u16 cons)
{
/*
* The other 16-bits in the register is read-only and writes to it
* are ignored by the hardware so we can save one ioread32() by
* filling the read-only bits with zeroes.
*/
iowrite32(cons, ring_desc_base(ring) + 8);
}
static void ring_iowrite_prod(struct tb_ring *ring, u16 prod)
{
/* See ring_iowrite_cons() above for explanation */
iowrite32(prod << 16, ring_desc_base(ring) + 8);
}
static void ring_iowrite32desc(struct tb_ring *ring, u32 value, u32 offset)
{
iowrite32(value, ring_desc_base(ring) + offset);
}
static void ring_iowrite64desc(struct tb_ring *ring, u64 value, u32 offset)
{
iowrite32(value, ring_desc_base(ring) + offset);
iowrite32(value >> 32, ring_desc_base(ring) + offset + 4);
}
static void ring_iowrite32options(struct tb_ring *ring, u32 value, u32 offset)
{
iowrite32(value, ring_options_base(ring) + offset);
}
static bool ring_full(struct tb_ring *ring)
{
return ((ring->head + 1) % ring->size) == ring->tail;
}
static bool ring_empty(struct tb_ring *ring)
{
return ring->head == ring->tail;
}
/*
* ring_write_descriptors() - post frames from ring->queue to the controller
*
* ring->lock is held.
*/
static void ring_write_descriptors(struct tb_ring *ring)
{
struct ring_frame *frame, *n;
struct ring_desc *descriptor;
list_for_each_entry_safe(frame, n, &ring->queue, list) {
if (ring_full(ring))
break;
list_move_tail(&frame->list, &ring->in_flight);
descriptor = &ring->descriptors[ring->head];
descriptor->phys = frame->buffer_phy;
descriptor->time = 0;
descriptor->flags = RING_DESC_POSTED | RING_DESC_INTERRUPT;
if (ring->is_tx) {
descriptor->length = frame->size;
descriptor->eof = frame->eof;
descriptor->sof = frame->sof;
}
ring->head = (ring->head + 1) % ring->size;
if (ring->is_tx)
ring_iowrite_prod(ring, ring->head);
else
ring_iowrite_cons(ring, ring->head);
}
}
/*
* ring_work() - progress completed frames
*
* If the ring is shutting down then all frames are marked as canceled and
* their callbacks are invoked.
*
* Otherwise we collect all completed frame from the ring buffer, write new
* frame to the ring buffer and invoke the callbacks for the completed frames.
*/
static void ring_work(struct work_struct *work)
{
struct tb_ring *ring = container_of(work, typeof(*ring), work);
struct ring_frame *frame;
bool canceled = false;
unsigned long flags;
LIST_HEAD(done);
spin_lock_irqsave(&ring->lock, flags);
if (!ring->running) {
/* Move all frames to done and mark them as canceled. */
list_splice_tail_init(&ring->in_flight, &done);
list_splice_tail_init(&ring->queue, &done);
canceled = true;
goto invoke_callback;
}
while (!ring_empty(ring)) {
if (!(ring->descriptors[ring->tail].flags
& RING_DESC_COMPLETED))
break;
frame = list_first_entry(&ring->in_flight, typeof(*frame),
list);
list_move_tail(&frame->list, &done);
if (!ring->is_tx) {
frame->size = ring->descriptors[ring->tail].length;
frame->eof = ring->descriptors[ring->tail].eof;
frame->sof = ring->descriptors[ring->tail].sof;
frame->flags = ring->descriptors[ring->tail].flags;
}
ring->tail = (ring->tail + 1) % ring->size;
}
ring_write_descriptors(ring);
invoke_callback:
/* allow callbacks to schedule new work */
spin_unlock_irqrestore(&ring->lock, flags);
while (!list_empty(&done)) {
frame = list_first_entry(&done, typeof(*frame), list);
/*
* The callback may reenqueue or delete frame.
* Do not hold on to it.
*/
list_del_init(&frame->list);
if (frame->callback)
frame->callback(ring, frame, canceled);
}
}
int __tb_ring_enqueue(struct tb_ring *ring, struct ring_frame *frame)
{
unsigned long flags;
int ret = 0;
spin_lock_irqsave(&ring->lock, flags);
if (ring->running) {
list_add_tail(&frame->list, &ring->queue);
ring_write_descriptors(ring);
} else {
ret = -ESHUTDOWN;
}
spin_unlock_irqrestore(&ring->lock, flags);
return ret;
}
EXPORT_SYMBOL_GPL(__tb_ring_enqueue);
/**
* tb_ring_poll() - Poll one completed frame from the ring
* @ring: Ring to poll
*
* This function can be called when @start_poll callback of the @ring
* has been called. It will read one completed frame from the ring and
* return it to the caller. Returns %NULL if there is no more completed
* frames.
*/
struct ring_frame *tb_ring_poll(struct tb_ring *ring)
{
struct ring_frame *frame = NULL;
unsigned long flags;
spin_lock_irqsave(&ring->lock, flags);
if (!ring->running)
goto unlock;
if (ring_empty(ring))
goto unlock;
if (ring->descriptors[ring->tail].flags & RING_DESC_COMPLETED) {
frame = list_first_entry(&ring->in_flight, typeof(*frame),
list);
list_del_init(&frame->list);
if (!ring->is_tx) {
frame->size = ring->descriptors[ring->tail].length;
frame->eof = ring->descriptors[ring->tail].eof;
frame->sof = ring->descriptors[ring->tail].sof;
frame->flags = ring->descriptors[ring->tail].flags;
}
ring->tail = (ring->tail + 1) % ring->size;
}
unlock:
spin_unlock_irqrestore(&ring->lock, flags);
return frame;
}
EXPORT_SYMBOL_GPL(tb_ring_poll);
static void __ring_interrupt_mask(struct tb_ring *ring, bool mask)
{
int idx = ring_interrupt_index(ring);
int reg = REG_RING_INTERRUPT_BASE + idx / 32 * 4;
int bit = idx % 32;
u32 val;
val = ioread32(ring->nhi->iobase + reg);
if (mask)
val &= ~BIT(bit);
else
val |= BIT(bit);
iowrite32(val, ring->nhi->iobase + reg);
}
/* Both @nhi->lock and @ring->lock should be held */
static void __ring_interrupt(struct tb_ring *ring)
{
if (!ring->running)
return;
if (ring->start_poll) {
__ring_interrupt_mask(ring, true);
ring->start_poll(ring->poll_data);
} else {
schedule_work(&ring->work);
}
}
/**
* tb_ring_poll_complete() - Re-start interrupt for the ring
* @ring: Ring to re-start the interrupt
*
* This will re-start (unmask) the ring interrupt once the user is done
* with polling.
*/
void tb_ring_poll_complete(struct tb_ring *ring)
{
unsigned long flags;
spin_lock_irqsave(&ring->nhi->lock, flags);
spin_lock(&ring->lock);
if (ring->start_poll)
__ring_interrupt_mask(ring, false);
spin_unlock(&ring->lock);
spin_unlock_irqrestore(&ring->nhi->lock, flags);
}
EXPORT_SYMBOL_GPL(tb_ring_poll_complete);
static void ring_clear_msix(const struct tb_ring *ring)
{
if (ring->nhi->quirks & QUIRK_AUTO_CLEAR_INT)
return;
if (ring->is_tx)
ioread32(ring->nhi->iobase + REG_RING_NOTIFY_BASE);
else
ioread32(ring->nhi->iobase + REG_RING_NOTIFY_BASE +
4 * (ring->nhi->hop_count / 32));
}
static irqreturn_t ring_msix(int irq, void *data)
{
struct tb_ring *ring = data;
spin_lock(&ring->nhi->lock);
ring_clear_msix(ring);
spin_lock(&ring->lock);
__ring_interrupt(ring);
spin_unlock(&ring->lock);
spin_unlock(&ring->nhi->lock);
return IRQ_HANDLED;
}
static int ring_request_msix(struct tb_ring *ring, bool no_suspend)
{
struct tb_nhi *nhi = ring->nhi;
unsigned long irqflags;
int ret;
if (!nhi->pdev->msix_enabled)
return 0;
ret = ida_simple_get(&nhi->msix_ida, 0, MSIX_MAX_VECS, GFP_KERNEL);
if (ret < 0)
return ret;
ring->vector = ret;
ret = pci_irq_vector(ring->nhi->pdev, ring->vector);
if (ret < 0)
goto err_ida_remove;
ring->irq = ret;
irqflags = no_suspend ? IRQF_NO_SUSPEND : 0;
ret = request_irq(ring->irq, ring_msix, irqflags, "thunderbolt", ring);
if (ret)
goto err_ida_remove;
return 0;
err_ida_remove:
ida_simple_remove(&nhi->msix_ida, ring->vector);
return ret;
}
static void ring_release_msix(struct tb_ring *ring)
{
if (ring->irq <= 0)
return;
free_irq(ring->irq, ring);
ida_simple_remove(&ring->nhi->msix_ida, ring->vector);
ring->vector = 0;
ring->irq = 0;
}
static int nhi_alloc_hop(struct tb_nhi *nhi, struct tb_ring *ring)
{
unsigned int start_hop = RING_FIRST_USABLE_HOPID;
int ret = 0;
if (nhi->quirks & QUIRK_E2E) {
start_hop = RING_FIRST_USABLE_HOPID + 1;
if (ring->flags & RING_FLAG_E2E && !ring->is_tx) {
dev_dbg(&nhi->pdev->dev, "quirking E2E TX HopID %u -> %u\n",
ring->e2e_tx_hop, RING_E2E_RESERVED_HOPID);
ring->e2e_tx_hop = RING_E2E_RESERVED_HOPID;
}
}
spin_lock_irq(&nhi->lock);
if (ring->hop < 0) {
unsigned int i;
/*
* Automatically allocate HopID from the non-reserved
* range 1 .. hop_count - 1.
*/
for (i = start_hop; i < nhi->hop_count; i++) {
if (ring->is_tx) {
if (!nhi->tx_rings[i]) {
ring->hop = i;
break;
}
} else {
if (!nhi->rx_rings[i]) {
ring->hop = i;
break;
}
}
}
}
if (ring->hop > 0 && ring->hop < start_hop) {
dev_warn(&nhi->pdev->dev, "invalid hop: %d\n", ring->hop);
ret = -EINVAL;
goto err_unlock;
}
if (ring->hop < 0 || ring->hop >= nhi->hop_count) {
dev_warn(&nhi->pdev->dev, "invalid hop: %d\n", ring->hop);
ret = -EINVAL;
goto err_unlock;
}
if (ring->is_tx && nhi->tx_rings[ring->hop]) {
dev_warn(&nhi->pdev->dev, "TX hop %d already allocated\n",
ring->hop);
ret = -EBUSY;
goto err_unlock;
} else if (!ring->is_tx && nhi->rx_rings[ring->hop]) {
dev_warn(&nhi->pdev->dev, "RX hop %d already allocated\n",
ring->hop);
ret = -EBUSY;
goto err_unlock;
}
if (ring->is_tx)
nhi->tx_rings[ring->hop] = ring;
else
nhi->rx_rings[ring->hop] = ring;
err_unlock:
spin_unlock_irq(&nhi->lock);
return ret;
}
static struct tb_ring *tb_ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
bool transmit, unsigned int flags,
int e2e_tx_hop, u16 sof_mask, u16 eof_mask,
void (*start_poll)(void *),
void *poll_data)
{
struct tb_ring *ring = NULL;
dev_dbg(&nhi->pdev->dev, "allocating %s ring %d of size %d\n",
transmit ? "TX" : "RX", hop, size);
ring = kzalloc(sizeof(*ring), GFP_KERNEL);
if (!ring)
return NULL;
spin_lock_init(&ring->lock);
INIT_LIST_HEAD(&ring->queue);
INIT_LIST_HEAD(&ring->in_flight);
INIT_WORK(&ring->work, ring_work);
ring->nhi = nhi;
ring->hop = hop;
ring->is_tx = transmit;
ring->size = size;
ring->flags = flags;
ring->e2e_tx_hop = e2e_tx_hop;
ring->sof_mask = sof_mask;
ring->eof_mask = eof_mask;
ring->head = 0;
ring->tail = 0;
ring->running = false;
ring->start_poll = start_poll;
ring->poll_data = poll_data;
ring->descriptors = dma_alloc_coherent(&ring->nhi->pdev->dev,
size * sizeof(*ring->descriptors),
&ring->descriptors_dma, GFP_KERNEL | __GFP_ZERO);
if (!ring->descriptors)
goto err_free_ring;
if (ring_request_msix(ring, flags & RING_FLAG_NO_SUSPEND))
goto err_free_descs;
if (nhi_alloc_hop(nhi, ring))
goto err_release_msix;
return ring;
err_release_msix:
ring_release_msix(ring);
err_free_descs:
dma_free_coherent(&ring->nhi->pdev->dev,
ring->size * sizeof(*ring->descriptors),
ring->descriptors, ring->descriptors_dma);
err_free_ring:
kfree(ring);
return NULL;
}
/**
* tb_ring_alloc_tx() - Allocate DMA ring for transmit
* @nhi: Pointer to the NHI the ring is to be allocated
* @hop: HopID (ring) to allocate
* @size: Number of entries in the ring
* @flags: Flags for the ring
*/
struct tb_ring *tb_ring_alloc_tx(struct tb_nhi *nhi, int hop, int size,
unsigned int flags)
{
return tb_ring_alloc(nhi, hop, size, true, flags, 0, 0, 0, NULL, NULL);
}
EXPORT_SYMBOL_GPL(tb_ring_alloc_tx);
/**
* tb_ring_alloc_rx() - Allocate DMA ring for receive
* @nhi: Pointer to the NHI the ring is to be allocated
* @hop: HopID (ring) to allocate. Pass %-1 for automatic allocation.
* @size: Number of entries in the ring
* @flags: Flags for the ring
* @e2e_tx_hop: Transmit HopID when E2E is enabled in @flags
* @sof_mask: Mask of PDF values that start a frame
* @eof_mask: Mask of PDF values that end a frame
* @start_poll: If not %NULL the ring will call this function when an
* interrupt is triggered and masked, instead of callback
* in each Rx frame.
* @poll_data: Optional data passed to @start_poll
*/
struct tb_ring *tb_ring_alloc_rx(struct tb_nhi *nhi, int hop, int size,
unsigned int flags, int e2e_tx_hop,
u16 sof_mask, u16 eof_mask,
void (*start_poll)(void *), void *poll_data)
{
return tb_ring_alloc(nhi, hop, size, false, flags, e2e_tx_hop, sof_mask, eof_mask,
start_poll, poll_data);
}
EXPORT_SYMBOL_GPL(tb_ring_alloc_rx);
/**
* tb_ring_start() - enable a ring
* @ring: Ring to start
*
* Must not be invoked in parallel with tb_ring_stop().
*/
void tb_ring_start(struct tb_ring *ring)
{
u16 frame_size;
u32 flags;
spin_lock_irq(&ring->nhi->lock);
spin_lock(&ring->lock);
if (ring->nhi->going_away)
goto err;
if (ring->running) {
dev_WARN(&ring->nhi->pdev->dev, "ring already started\n");
goto err;
}
dev_dbg(&ring->nhi->pdev->dev, "starting %s %d\n",
RING_TYPE(ring), ring->hop);
if (ring->flags & RING_FLAG_FRAME) {
/* Means 4096 */
frame_size = 0;
flags = RING_FLAG_ENABLE;
} else {
frame_size = TB_FRAME_SIZE;
flags = RING_FLAG_ENABLE | RING_FLAG_RAW;
}
ring_iowrite64desc(ring, ring->descriptors_dma, 0);
if (ring->is_tx) {
ring_iowrite32desc(ring, ring->size, 12);
ring_iowrite32options(ring, 0, 4); /* time releated ? */
ring_iowrite32options(ring, flags, 0);
} else {
u32 sof_eof_mask = ring->sof_mask << 16 | ring->eof_mask;
ring_iowrite32desc(ring, (frame_size << 16) | ring->size, 12);
ring_iowrite32options(ring, sof_eof_mask, 4);
ring_iowrite32options(ring, flags, 0);
}
/*
* Now that the ring valid bit is set we can configure E2E if
* enabled for the ring.
*/
if (ring->flags & RING_FLAG_E2E) {
if (!ring->is_tx) {
u32 hop;
hop = ring->e2e_tx_hop << REG_RX_OPTIONS_E2E_HOP_SHIFT;
hop &= REG_RX_OPTIONS_E2E_HOP_MASK;
flags |= hop;
dev_dbg(&ring->nhi->pdev->dev,
"enabling E2E for %s %d with TX HopID %d\n",
RING_TYPE(ring), ring->hop, ring->e2e_tx_hop);
} else {
dev_dbg(&ring->nhi->pdev->dev, "enabling E2E for %s %d\n",
RING_TYPE(ring), ring->hop);
}
flags |= RING_FLAG_E2E_FLOW_CONTROL;
ring_iowrite32options(ring, flags, 0);
}
ring_interrupt_active(ring, true);
ring->running = true;
err:
spin_unlock(&ring->lock);
spin_unlock_irq(&ring->nhi->lock);
}
EXPORT_SYMBOL_GPL(tb_ring_start);
/**
* tb_ring_stop() - shutdown a ring
* @ring: Ring to stop
*
* Must not be invoked from a callback.
*
* This method will disable the ring. Further calls to
* tb_ring_tx/tb_ring_rx will return -ESHUTDOWN until ring_stop has been
* called.
*
* All enqueued frames will be canceled and their callbacks will be executed
* with frame->canceled set to true (on the callback thread). This method
* returns only after all callback invocations have finished.
*/
void tb_ring_stop(struct tb_ring *ring)
{
spin_lock_irq(&ring->nhi->lock);
spin_lock(&ring->lock);
dev_dbg(&ring->nhi->pdev->dev, "stopping %s %d\n",
RING_TYPE(ring), ring->hop);
if (ring->nhi->going_away)
goto err;
if (!ring->running) {
dev_WARN(&ring->nhi->pdev->dev, "%s %d already stopped\n",
RING_TYPE(ring), ring->hop);
goto err;
}
ring_interrupt_active(ring, false);
ring_iowrite32options(ring, 0, 0);
ring_iowrite64desc(ring, 0, 0);
ring_iowrite32desc(ring, 0, 8);
ring_iowrite32desc(ring, 0, 12);
ring->head = 0;
ring->tail = 0;
ring->running = false;
err:
spin_unlock(&ring->lock);
spin_unlock_irq(&ring->nhi->lock);
/*
* schedule ring->work to invoke callbacks on all remaining frames.
*/
schedule_work(&ring->work);
flush_work(&ring->work);
}
EXPORT_SYMBOL_GPL(tb_ring_stop);
/*
* tb_ring_free() - free ring
*
* When this method returns all invocations of ring->callback will have
* finished.
*
* Ring must be stopped.
*
* Must NOT be called from ring_frame->callback!
*/
void tb_ring_free(struct tb_ring *ring)
{
spin_lock_irq(&ring->nhi->lock);
/*
* Dissociate the ring from the NHI. This also ensures that
* nhi_interrupt_work cannot reschedule ring->work.
*/
if (ring->is_tx)
ring->nhi->tx_rings[ring->hop] = NULL;
else
ring->nhi->rx_rings[ring->hop] = NULL;
if (ring->running) {
dev_WARN(&ring->nhi->pdev->dev, "%s %d still running\n",
RING_TYPE(ring), ring->hop);
}
spin_unlock_irq(&ring->nhi->lock);
ring_release_msix(ring);
dma_free_coherent(&ring->nhi->pdev->dev,
ring->size * sizeof(*ring->descriptors),
ring->descriptors, ring->descriptors_dma);
ring->descriptors = NULL;
ring->descriptors_dma = 0;
dev_dbg(&ring->nhi->pdev->dev, "freeing %s %d\n", RING_TYPE(ring),
ring->hop);
/*
* ring->work can no longer be scheduled (it is scheduled only
* by nhi_interrupt_work, ring_stop and ring_msix). Wait for it
* to finish before freeing the ring.
*/
flush_work(&ring->work);
kfree(ring);
}
EXPORT_SYMBOL_GPL(tb_ring_free);
/**
* nhi_mailbox_cmd() - Send a command through NHI mailbox
* @nhi: Pointer to the NHI structure
* @cmd: Command to send
* @data: Data to be send with the command
*
* Sends mailbox command to the firmware running on NHI. Returns %0 in
* case of success and negative errno in case of failure.
*/
int nhi_mailbox_cmd(struct tb_nhi *nhi, enum nhi_mailbox_cmd cmd, u32 data)
{
ktime_t timeout;
u32 val;
iowrite32(data, nhi->iobase + REG_INMAIL_DATA);
val = ioread32(nhi->iobase + REG_INMAIL_CMD);
val &= ~(REG_INMAIL_CMD_MASK | REG_INMAIL_ERROR);
val |= REG_INMAIL_OP_REQUEST | cmd;
iowrite32(val, nhi->iobase + REG_INMAIL_CMD);
timeout = ktime_add_ms(ktime_get(), NHI_MAILBOX_TIMEOUT);
do {
val = ioread32(nhi->iobase + REG_INMAIL_CMD);
if (!(val & REG_INMAIL_OP_REQUEST))
break;
usleep_range(10, 20);
} while (ktime_before(ktime_get(), timeout));
if (val & REG_INMAIL_OP_REQUEST)
return -ETIMEDOUT;
if (val & REG_INMAIL_ERROR)
return -EIO;
return 0;
}
/**
* nhi_mailbox_mode() - Return current firmware operation mode
* @nhi: Pointer to the NHI structure
*
* The function reads current firmware operation mode using NHI mailbox
* registers and returns it to the caller.
*/
enum nhi_fw_mode nhi_mailbox_mode(struct tb_nhi *nhi)
{
u32 val;
val = ioread32(nhi->iobase + REG_OUTMAIL_CMD);
val &= REG_OUTMAIL_CMD_OPMODE_MASK;
val >>= REG_OUTMAIL_CMD_OPMODE_SHIFT;
return (enum nhi_fw_mode)val;
}
static void nhi_interrupt_work(struct work_struct *work)
{
struct tb_nhi *nhi = container_of(work, typeof(*nhi), interrupt_work);
int value = 0; /* Suppress uninitialized usage warning. */
int bit;
int hop = -1;
int type = 0; /* current interrupt type 0: TX, 1: RX, 2: RX overflow */
struct tb_ring *ring;
spin_lock_irq(&nhi->lock);
/*
* Starting at REG_RING_NOTIFY_BASE there are three status bitfields
* (TX, RX, RX overflow). We iterate over the bits and read a new
* dwords as required. The registers are cleared on read.
*/
for (bit = 0; bit < 3 * nhi->hop_count; bit++) {
if (bit % 32 == 0)
value = ioread32(nhi->iobase
+ REG_RING_NOTIFY_BASE
+ 4 * (bit / 32));
if (++hop == nhi->hop_count) {
hop = 0;
type++;
}
if ((value & (1 << (bit % 32))) == 0)
continue;
if (type == 2) {
dev_warn(&nhi->pdev->dev,
"RX overflow for ring %d\n",
hop);
continue;
}
if (type == 0)
ring = nhi->tx_rings[hop];
else
ring = nhi->rx_rings[hop];
if (ring == NULL) {
dev_warn(&nhi->pdev->dev,
"got interrupt for inactive %s ring %d\n",
type ? "RX" : "TX",
hop);
continue;
}
spin_lock(&ring->lock);
__ring_interrupt(ring);
spin_unlock(&ring->lock);
}
spin_unlock_irq(&nhi->lock);
}
static irqreturn_t nhi_msi(int irq, void *data)
{
struct tb_nhi *nhi = data;
schedule_work(&nhi->interrupt_work);
return IRQ_HANDLED;
}
static int __nhi_suspend_noirq(struct device *dev, bool wakeup)
{
struct pci_dev *pdev = to_pci_dev(dev);
struct tb *tb = pci_get_drvdata(pdev);
struct tb_nhi *nhi = tb->nhi;
int ret;
ret = tb_domain_suspend_noirq(tb);
if (ret)
return ret;
if (nhi->ops && nhi->ops->suspend_noirq) {
ret = nhi->ops->suspend_noirq(tb->nhi, wakeup);
if (ret)
return ret;
}
return 0;
}
static int nhi_suspend_noirq(struct device *dev)
{
return __nhi_suspend_noirq(dev, device_may_wakeup(dev));
}
static int nhi_freeze_noirq(struct device *dev)
{
struct pci_dev *pdev = to_pci_dev(dev);
struct tb *tb = pci_get_drvdata(pdev);
return tb_domain_freeze_noirq(tb);
}
static int nhi_thaw_noirq(struct device *dev)
{
struct pci_dev *pdev = to_pci_dev(dev);
struct tb *tb = pci_get_drvdata(pdev);
return tb_domain_thaw_noirq(tb);
}
static bool nhi_wake_supported(struct pci_dev *pdev)
{
u8 val;
/*
* If power rails are sustainable for wakeup from S4 this
* property is set by the BIOS.
*/
if (device_property_read_u8(&pdev->dev, "WAKE_SUPPORTED", &val))
return !!val;
return true;
}
static int nhi_poweroff_noirq(struct device *dev)
{
struct pci_dev *pdev = to_pci_dev(dev);
bool wakeup;
wakeup = device_may_wakeup(dev) && nhi_wake_supported(pdev);
return __nhi_suspend_noirq(dev, wakeup);
}
static void nhi_enable_int_throttling(struct tb_nhi *nhi)
{
/* Throttling is specified in 256ns increments */
u32 throttle = DIV_ROUND_UP(128 * NSEC_PER_USEC, 256);
unsigned int i;
/*
* Configure interrupt throttling for all vectors even if we
* only use few.
*/
for (i = 0; i < MSIX_MAX_VECS; i++) {
u32 reg = REG_INT_THROTTLING_RATE + i * 4;
iowrite32(throttle, nhi->iobase + reg);
}
}
static int nhi_resume_noirq(struct device *dev)
{
struct pci_dev *pdev = to_pci_dev(dev);
struct tb *tb = pci_get_drvdata(pdev);
struct tb_nhi *nhi = tb->nhi;
int ret;
/*
* Check that the device is still there. It may be that the user
* unplugged last device which causes the host controller to go
* away on PCs.
*/
if (!pci_device_is_present(pdev)) {
nhi->going_away = true;
} else {
if (nhi->ops && nhi->ops->resume_noirq) {
ret = nhi->ops->resume_noirq(nhi);
if (ret)
return ret;
}
nhi_enable_int_throttling(tb->nhi);
}
return tb_domain_resume_noirq(tb);
}
static int nhi_suspend(struct device *dev)
{
struct pci_dev *pdev = to_pci_dev(dev);
struct tb *tb = pci_get_drvdata(pdev);
return tb_domain_suspend(tb);
}
static void nhi_complete(struct device *dev)
{
struct pci_dev *pdev = to_pci_dev(dev);
struct tb *tb = pci_get_drvdata(pdev);
/*
* If we were runtime suspended when system suspend started,
* schedule runtime resume now. It should bring the domain back
* to functional state.
*/
if (pm_runtime_suspended(&pdev->dev))
pm_runtime_resume(&pdev->dev);
else
tb_domain_complete(tb);
}
static int nhi_runtime_suspend(struct device *dev)
{
struct pci_dev *pdev = to_pci_dev(dev);
struct tb *tb = pci_get_drvdata(pdev);
struct tb_nhi *nhi = tb->nhi;
int ret;
ret = tb_domain_runtime_suspend(tb);
if (ret)
return ret;
if (nhi->ops && nhi->ops->runtime_suspend) {
ret = nhi->ops->runtime_suspend(tb->nhi);
if (ret)
return ret;
}
return 0;
}
static int nhi_runtime_resume(struct device *dev)
{
struct pci_dev *pdev = to_pci_dev(dev);
struct tb *tb = pci_get_drvdata(pdev);
struct tb_nhi *nhi = tb->nhi;
int ret;
if (nhi->ops && nhi->ops->runtime_resume) {
ret = nhi->ops->runtime_resume(nhi);
if (ret)
return ret;
}
nhi_enable_int_throttling(nhi);
return tb_domain_runtime_resume(tb);
}
static void nhi_shutdown(struct tb_nhi *nhi)
{
int i;
dev_dbg(&nhi->pdev->dev, "shutdown\n");
for (i = 0; i < nhi->hop_count; i++) {
if (nhi->tx_rings[i])
dev_WARN(&nhi->pdev->dev,
"TX ring %d is still active\n", i);
if (nhi->rx_rings[i])
dev_WARN(&nhi->pdev->dev,
"RX ring %d is still active\n", i);
}
nhi_disable_interrupts(nhi);
/*
* We have to release the irq before calling flush_work. Otherwise an
* already executing IRQ handler could call schedule_work again.
*/
if (!nhi->pdev->msix_enabled) {
devm_free_irq(&nhi->pdev->dev, nhi->pdev->irq, nhi);
flush_work(&nhi->interrupt_work);
}
ida_destroy(&nhi->msix_ida);
if (nhi->ops && nhi->ops->shutdown)
nhi->ops->shutdown(nhi);
}
static void nhi_check_quirks(struct tb_nhi *nhi)
{
if (nhi->pdev->vendor == PCI_VENDOR_ID_INTEL) {
/*
* Intel hardware supports auto clear of the interrupt
* status register right after interrupt is being
* issued.
*/
nhi->quirks |= QUIRK_AUTO_CLEAR_INT;
switch (nhi->pdev->device) {
case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_2C_NHI:
case PCI_DEVICE_ID_INTEL_FALCON_RIDGE_4C_NHI:
/*
* Falcon Ridge controller needs the end-to-end
* flow control workaround to avoid losing Rx
* packets when RING_FLAG_E2E is set.
*/
nhi->quirks |= QUIRK_E2E;
break;
}
}
}
static int nhi_check_iommu_pdev(struct pci_dev *pdev, void *data)
{
if (!pdev->external_facing ||
!device_iommu_capable(&pdev->dev, IOMMU_CAP_PRE_BOOT_PROTECTION))
return 0;
*(bool *)data = true;
return 1; /* Stop walking */
}
static void nhi_check_iommu(struct tb_nhi *nhi)
{
struct pci_bus *bus = nhi->pdev->bus;
bool port_ok = false;
/*
* Ideally what we'd do here is grab every PCI device that
* represents a tunnelling adapter for this NHI and check their
* status directly, but unfortunately USB4 seems to make it
* obnoxiously difficult to reliably make any correlation.
*
* So for now we'll have to bodge it... Hoping that the system
* is at least sane enough that an adapter is in the same PCI
* segment as its NHI, if we can find *something* on that segment
* which meets the requirements for Kernel DMA Protection, we'll
* take that to imply that firmware is aware and has (hopefully)
* done the right thing in general. We need to know that the PCI
* layer has seen the ExternalFacingPort property which will then
* inform the IOMMU layer to enforce the complete "untrusted DMA"
* flow, but also that the IOMMU driver itself can be trusted not
* to have been subverted by a pre-boot DMA attack.
*/
while (bus->parent)
bus = bus->parent;
pci_walk_bus(bus, nhi_check_iommu_pdev, &port_ok);
nhi->iommu_dma_protection = port_ok;
dev_dbg(&nhi->pdev->dev, "IOMMU DMA protection is %s\n",
str_enabled_disabled(port_ok));
}
static int nhi_init_msi(struct tb_nhi *nhi)
{
struct pci_dev *pdev = nhi->pdev;
struct device *dev = &pdev->dev;
int res, irq, nvec;
/* In case someone left them on. */
nhi_disable_interrupts(nhi);
nhi_enable_int_throttling(nhi);
ida_init(&nhi->msix_ida);
/*
* The NHI has 16 MSI-X vectors or a single MSI. We first try to
* get all MSI-X vectors and if we succeed, each ring will have
* one MSI-X. If for some reason that does not work out, we
* fallback to a single MSI.
*/
nvec = pci_alloc_irq_vectors(pdev, MSIX_MIN_VECS, MSIX_MAX_VECS,
PCI_IRQ_MSIX);
if (nvec < 0) {
nvec = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
if (nvec < 0)
return nvec;
INIT_WORK(&nhi->interrupt_work, nhi_interrupt_work);
irq = pci_irq_vector(nhi->pdev, 0);
if (irq < 0)
return irq;
res = devm_request_irq(&pdev->dev, irq, nhi_msi,
IRQF_NO_SUSPEND, "thunderbolt", nhi);
if (res)
return dev_err_probe(dev, res, "request_irq failed, aborting\n");
}
return 0;
}
static bool nhi_imr_valid(struct pci_dev *pdev)
{
u8 val;
if (!device_property_read_u8(&pdev->dev, "IMR_VALID", &val))
return !!val;
return true;
}
static struct tb *nhi_select_cm(struct tb_nhi *nhi)
{
struct tb *tb;
/*
* USB4 case is simple. If we got control of any of the
* capabilities, we use software CM.
*/
if (tb_acpi_is_native())
return tb_probe(nhi);
/*
* Either firmware based CM is running (we did not get control
* from the firmware) or this is pre-USB4 PC so try first
* firmware CM and then fallback to software CM.
*/
tb = icm_probe(nhi);
if (!tb)
tb = tb_probe(nhi);
return tb;
}
static int nhi_probe(struct pci_dev *pdev, const struct pci_device_id *id)
{
struct device *dev = &pdev->dev;
struct tb_nhi *nhi;
struct tb *tb;
int res;
if (!nhi_imr_valid(pdev))
return dev_err_probe(dev, -ENODEV, "firmware image not valid, aborting\n");
res = pcim_enable_device(pdev);
if (res)
return dev_err_probe(dev, res, "cannot enable PCI device, aborting\n");
res = pcim_iomap_regions(pdev, 1 << 0, "thunderbolt");
if (res)
return dev_err_probe(dev, res, "cannot obtain PCI resources, aborting\n");
nhi = devm_kzalloc(&pdev->dev, sizeof(*nhi), GFP_KERNEL);
if (!nhi)
return -ENOMEM;
nhi->pdev = pdev;
nhi->ops = (const struct tb_nhi_ops *)id->driver_data;
/* cannot fail - table is allocated in pcim_iomap_regions */
nhi->iobase = pcim_iomap_table(pdev)[0];
nhi->hop_count = ioread32(nhi->iobase + REG_HOP_COUNT) & 0x3ff;
dev_dbg(dev, "total paths: %d\n", nhi->hop_count);
nhi->tx_rings = devm_kcalloc(&pdev->dev, nhi->hop_count,
sizeof(*nhi->tx_rings), GFP_KERNEL);
nhi->rx_rings = devm_kcalloc(&pdev->dev, nhi->hop_count,
sizeof(*nhi->rx_rings), GFP_KERNEL);
if (!nhi->tx_rings || !nhi->rx_rings)
return -ENOMEM;
nhi_check_quirks(nhi);
nhi_check_iommu(nhi);
res = nhi_init_msi(nhi);
if (res)
return dev_err_probe(dev, res, "cannot enable MSI, aborting\n");
spin_lock_init(&nhi->lock);
res = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
if (res)
return dev_err_probe(dev, res, "failed to set DMA mask\n");
pci_set_master(pdev);
if (nhi->ops && nhi->ops->init) {
res = nhi->ops->init(nhi);
if (res)
return res;
}
tb = nhi_select_cm(nhi);
if (!tb)
return dev_err_probe(dev, -ENODEV,
"failed to determine connection manager, aborting\n");
dev_dbg(dev, "NHI initialized, starting thunderbolt\n");
res = tb_domain_add(tb);
if (res) {
/*
* At this point the RX/TX rings might already have been
* activated. Do a proper shutdown.
*/
tb_domain_put(tb);
nhi_shutdown(nhi);
return res;
}
pci_set_drvdata(pdev, tb);
device_wakeup_enable(&pdev->dev);
pm_runtime_allow(&pdev->dev);
pm_runtime_set_autosuspend_delay(&pdev->dev, TB_AUTOSUSPEND_DELAY);
pm_runtime_use_autosuspend(&pdev->dev);
pm_runtime_put_autosuspend(&pdev->dev);
return 0;
}
static void nhi_remove(struct pci_dev *pdev)
{
struct tb *tb = pci_get_drvdata(pdev);
struct tb_nhi *nhi = tb->nhi;
pm_runtime_get_sync(&pdev->dev);
pm_runtime_dont_use_autosuspend(&pdev->dev);
pm_runtime_forbid(&pdev->dev);
tb_domain_remove(tb);
nhi_shutdown(nhi);
}
/*
* The tunneled pci bridges are siblings of us. Use resume_noirq to reenable
* the tunnels asap. A corresponding pci quirk blocks the downstream bridges
* resume_noirq until we are done.
*/
static const struct dev_pm_ops nhi_pm_ops = {
.suspend_noirq = nhi_suspend_noirq,
.resume_noirq = nhi_resume_noirq,
.freeze_noirq = nhi_freeze_noirq, /*
* we just disable hotplug, the
* pci-tunnels stay alive.
*/
.thaw_noirq = nhi_thaw_noirq,
.restore_noirq = nhi_resume_noirq,
.suspend = nhi_suspend,
.poweroff_noirq = nhi_poweroff_noirq,
.poweroff = nhi_suspend,
.complete = nhi_complete,
.runtime_suspend = nhi_runtime_suspend,
.runtime_resume = nhi_runtime_resume,
};
static struct pci_device_id nhi_ids[] = {
/*
* We have to specify class, the TB bridges use the same device and
* vendor (sub)id on gen 1 and gen 2 controllers.
*/
{
.class = PCI_CLASS_SYSTEM_OTHER << 8, .class_mask = ~0,
.vendor = PCI_VENDOR_ID_INTEL,
.device = PCI_DEVICE_ID_INTEL_LIGHT_RIDGE,
.subvendor = 0x2222, .subdevice = 0x1111,
},
{
.class = PCI_CLASS_SYSTEM_OTHER << 8, .class_mask = ~0,
.vendor = PCI_VENDOR_ID_INTEL,
.device = PCI_DEVICE_ID_INTEL_CACTUS_RIDGE_4C,
.subvendor = 0x2222, .subdevice = 0x1111,
},
{
.class = PCI_CLASS_SYSTEM_OTHER << 8, .class_mask = ~0,
.vendor = PCI_VENDOR_ID_INTEL,
.device = PCI_DEVICE_ID_INTEL_FALCON_RIDGE_2C_NHI,
.subvendor = PCI_ANY_ID, .subdevice = PCI_ANY_ID,
},
{
.class = PCI_CLASS_SYSTEM_OTHER << 8, .class_mask = ~0,
.vendor = PCI_VENDOR_ID_INTEL,
.device = PCI_DEVICE_ID_INTEL_FALCON_RIDGE_4C_NHI,
.subvendor = PCI_ANY_ID, .subdevice = PCI_ANY_ID,
},
/* Thunderbolt 3 */
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_2C_NHI) },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_4C_NHI) },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_USBONLY_NHI) },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_LP_NHI) },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_LP_USBONLY_NHI) },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_C_2C_NHI) },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_C_4C_NHI) },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ALPINE_RIDGE_C_USBONLY_NHI) },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_TITAN_RIDGE_2C_NHI) },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_TITAN_RIDGE_4C_NHI) },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ICL_NHI0),
.driver_data = (kernel_ulong_t)&icl_nhi_ops },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ICL_NHI1),
.driver_data = (kernel_ulong_t)&icl_nhi_ops },
/* Thunderbolt 4 */
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_TGL_NHI0),
.driver_data = (kernel_ulong_t)&icl_nhi_ops },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_TGL_NHI1),
.driver_data = (kernel_ulong_t)&icl_nhi_ops },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_TGL_H_NHI0),
.driver_data = (kernel_ulong_t)&icl_nhi_ops },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_TGL_H_NHI1),
.driver_data = (kernel_ulong_t)&icl_nhi_ops },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ADL_NHI0),
.driver_data = (kernel_ulong_t)&icl_nhi_ops },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ADL_NHI1),
.driver_data = (kernel_ulong_t)&icl_nhi_ops },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_RPL_NHI0),
.driver_data = (kernel_ulong_t)&icl_nhi_ops },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_RPL_NHI1),
.driver_data = (kernel_ulong_t)&icl_nhi_ops },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_MTL_M_NHI0),
.driver_data = (kernel_ulong_t)&icl_nhi_ops },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_MTL_P_NHI0),
.driver_data = (kernel_ulong_t)&icl_nhi_ops },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_MTL_P_NHI1),
.driver_data = (kernel_ulong_t)&icl_nhi_ops },
/* Any USB4 compliant host */
{ PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_USB_USB4, ~0) },
{ 0,}
};
MODULE_DEVICE_TABLE(pci, nhi_ids);
MODULE_LICENSE("GPL");
static struct pci_driver nhi_driver = {
.name = "thunderbolt",
.id_table = nhi_ids,
.probe = nhi_probe,
.remove = nhi_remove,
.shutdown = nhi_remove,
.driver.pm = &nhi_pm_ops,
};
static int __init nhi_init(void)
{
int ret;
ret = tb_domain_init();
if (ret)
return ret;
ret = pci_register_driver(&nhi_driver);
if (ret)
tb_domain_exit();
return ret;
}
static void __exit nhi_unload(void)
{
pci_unregister_driver(&nhi_driver);
tb_domain_exit();
}
rootfs_initcall(nhi_init);
module_exit(nhi_unload);