[PATCH 09/16] thunderbolt: Export ring handling functions to modules

From: Mika Westerberg
Date: Mon Sep 18 2017 - 11:31:07 EST


These are used by Thunderbolt services to send and receive frames over
the high-speed DMA rings.

We also put the functions to tb_ namespace to make sure we do not
collide with others and add missing kernel-doc comments for the exported
functions.

Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
Reviewed-by: Michael Jamet <michael.jamet@xxxxxxxxx>
Reviewed-by: Yehezkel Bernat <yehezkel.bernat@xxxxxxxxx>
---
drivers/thunderbolt/ctl.c | 20 +++---
drivers/thunderbolt/nhi.c | 62 +++++++++++------
drivers/thunderbolt/nhi.h | 147 +----------------------------------------
include/linux/thunderbolt.h | 158 ++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 211 insertions(+), 176 deletions(-)

diff --git a/drivers/thunderbolt/ctl.c b/drivers/thunderbolt/ctl.c
index 05400b77dcd7..dd10789e1dbb 100644
--- a/drivers/thunderbolt/ctl.c
+++ b/drivers/thunderbolt/ctl.c
@@ -359,7 +359,7 @@ static int tb_ctl_tx(struct tb_ctl *ctl, const void *data, size_t len,
cpu_to_be32_array(pkg->buffer, data, len / 4);
*(__be32 *) (pkg->buffer + len) = tb_crc(pkg->buffer, len);

- res = ring_tx(ctl->tx, &pkg->frame);
+ res = tb_ring_tx(ctl->tx, &pkg->frame);
if (res) /* ring is stopped */
tb_ctl_pkg_free(pkg);
return res;
@@ -376,7 +376,7 @@ static bool tb_ctl_handle_event(struct tb_ctl *ctl, enum tb_cfg_pkg_type type,

static void tb_ctl_rx_submit(struct ctl_pkg *pkg)
{
- ring_rx(pkg->ctl->rx, &pkg->frame); /*
+ tb_ring_rx(pkg->ctl->rx, &pkg->frame); /*
* We ignore failures during stop.
* All rx packets are referenced
* from ctl->rx_packets, so we do
@@ -614,11 +614,11 @@ struct tb_ctl *tb_ctl_alloc(struct tb_nhi *nhi, event_cb cb, void *cb_data)
if (!ctl->frame_pool)
goto err;

- ctl->tx = ring_alloc_tx(nhi, 0, 10, RING_FLAG_NO_SUSPEND);
+ ctl->tx = tb_ring_alloc_tx(nhi, 0, 10, RING_FLAG_NO_SUSPEND);
if (!ctl->tx)
goto err;

- ctl->rx = ring_alloc_rx(nhi, 0, 10, RING_FLAG_NO_SUSPEND, 0xffff,
+ ctl->rx = tb_ring_alloc_rx(nhi, 0, 10, RING_FLAG_NO_SUSPEND, 0xffff,
0xffff);
if (!ctl->rx)
goto err;
@@ -652,9 +652,9 @@ void tb_ctl_free(struct tb_ctl *ctl)
return;

if (ctl->rx)
- ring_free(ctl->rx);
+ tb_ring_free(ctl->rx);
if (ctl->tx)
- ring_free(ctl->tx);
+ tb_ring_free(ctl->tx);

/* free RX packets */
for (i = 0; i < TB_CTL_RX_PKG_COUNT; i++)
@@ -673,8 +673,8 @@ void tb_ctl_start(struct tb_ctl *ctl)
{
int i;
tb_ctl_info(ctl, "control channel starting...\n");
- ring_start(ctl->tx); /* is used to ack hotplug packets, start first */
- ring_start(ctl->rx);
+ tb_ring_start(ctl->tx); /* is used to ack hotplug packets, start first */
+ tb_ring_start(ctl->rx);
for (i = 0; i < TB_CTL_RX_PKG_COUNT; i++)
tb_ctl_rx_submit(ctl->rx_packets[i]);

@@ -695,8 +695,8 @@ void tb_ctl_stop(struct tb_ctl *ctl)
ctl->running = false;
mutex_unlock(&ctl->request_queue_lock);

- ring_stop(ctl->rx);
- ring_stop(ctl->tx);
+ tb_ring_stop(ctl->rx);
+ tb_ring_stop(ctl->tx);

if (!list_empty(&ctl->request_queue))
tb_ctl_WARN(ctl, "dangling request in request_queue\n");
diff --git a/drivers/thunderbolt/nhi.c b/drivers/thunderbolt/nhi.c
index cde8b6d46147..4704ccd20c84 100644
--- a/drivers/thunderbolt/nhi.c
+++ b/drivers/thunderbolt/nhi.c
@@ -253,7 +253,7 @@ static void ring_work(struct work_struct *work)
}
}

-int __ring_enqueue(struct tb_ring *ring, struct ring_frame *frame)
+int __tb_ring_enqueue(struct tb_ring *ring, struct ring_frame *frame)
{
int ret = 0;
mutex_lock(&ring->lock);
@@ -266,6 +266,7 @@ int __ring_enqueue(struct tb_ring *ring, struct ring_frame *frame)
mutex_unlock(&ring->lock);
return ret;
}
+EXPORT_SYMBOL_GPL(__tb_ring_enqueue);

static irqreturn_t ring_msix(int irq, void *data)
{
@@ -309,9 +310,9 @@ static void ring_release_msix(struct tb_ring *ring)
ring->irq = 0;
}

-static struct tb_ring *ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
- bool transmit, unsigned int flags,
- u16 sof_mask, u16 eof_mask)
+static struct tb_ring *tb_ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
+ bool transmit, unsigned int flags,
+ u16 sof_mask, u16 eof_mask)
{
struct tb_ring *ring = NULL;
dev_info(&nhi->pdev->dev, "allocating %s ring %d of size %d\n",
@@ -377,24 +378,42 @@ static struct tb_ring *ring_alloc(struct tb_nhi *nhi, u32 hop, int size,
return NULL;
}

-struct tb_ring *ring_alloc_tx(struct tb_nhi *nhi, int hop, int size,
- unsigned int flags)
+/**
+ * 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 ring_alloc(nhi, hop, size, true, flags, 0, 0);
+ return tb_ring_alloc(nhi, hop, size, true, flags, 0, 0);
}
+EXPORT_SYMBOL_GPL(tb_ring_alloc_tx);

-struct tb_ring *ring_alloc_rx(struct tb_nhi *nhi, int hop, int size,
- unsigned int flags, u16 sof_mask, u16 eof_mask)
+/**
+ * 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
+ * @size: Number of entries in the ring
+ * @flags: Flags for the ring
+ * @sof_mask: Mask of PDF values that start a frame
+ * @eof_mask: Mask of PDF values that end a frame
+ */
+struct tb_ring *tb_ring_alloc_rx(struct tb_nhi *nhi, int hop, int size,
+ unsigned int flags, u16 sof_mask, u16 eof_mask)
{
- return ring_alloc(nhi, hop, size, false, flags, sof_mask, eof_mask);
+ return tb_ring_alloc(nhi, hop, size, false, flags, sof_mask, eof_mask);
}
+EXPORT_SYMBOL_GPL(tb_ring_alloc_rx);

/**
- * ring_start() - enable a ring
+ * tb_ring_start() - enable a ring
*
- * Must not be invoked in parallel with ring_stop().
+ * Must not be invoked in parallel with tb_ring_stop().
*/
-void ring_start(struct tb_ring *ring)
+void tb_ring_start(struct tb_ring *ring)
{
u16 frame_size;
u32 flags;
@@ -450,21 +469,22 @@ void ring_start(struct tb_ring *ring)
mutex_unlock(&ring->lock);
mutex_unlock(&ring->nhi->lock);
}
-
+EXPORT_SYMBOL_GPL(tb_ring_start);

/**
- * ring_stop() - shutdown a ring
+ * tb_ring_stop() - shutdown a ring
*
* Must not be invoked from a callback.
*
- * This method will disable the ring. Further calls to ring_tx/ring_rx will
- * return -ESHUTDOWN until ring_stop has been called.
+ * 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 ring_stop(struct tb_ring *ring)
+void tb_ring_stop(struct tb_ring *ring)
{
mutex_lock(&ring->nhi->lock);
mutex_lock(&ring->lock);
@@ -497,9 +517,10 @@ void ring_stop(struct tb_ring *ring)
schedule_work(&ring->work);
flush_work(&ring->work);
}
+EXPORT_SYMBOL_GPL(tb_ring_stop);

/*
- * ring_free() - free ring
+ * tb_ring_free() - free ring
*
* When this method returns all invocations of ring->callback will have
* finished.
@@ -508,7 +529,7 @@ void ring_stop(struct tb_ring *ring)
*
* Must NOT be called from ring_frame->callback!
*/
-void ring_free(struct tb_ring *ring)
+void tb_ring_free(struct tb_ring *ring)
{
mutex_lock(&ring->nhi->lock);
/*
@@ -550,6 +571,7 @@ void ring_free(struct tb_ring *ring)
mutex_destroy(&ring->lock);
kfree(ring);
}
+EXPORT_SYMBOL_GPL(tb_ring_free);

/**
* nhi_mailbox_cmd() - Send a command through NHI mailbox
diff --git a/drivers/thunderbolt/nhi.h b/drivers/thunderbolt/nhi.h
index 4503ddbeccb3..771d09ca5dc5 100644
--- a/drivers/thunderbolt/nhi.h
+++ b/drivers/thunderbolt/nhi.h
@@ -7,152 +7,7 @@
#ifndef DSL3510_H_
#define DSL3510_H_

-#include <linux/idr.h>
-#include <linux/mutex.h>
-#include <linux/workqueue.h>
-
-/**
- * struct tb_nhi - thunderbolt native host interface
- * @lock: Must be held during ring creation/destruction. Is acquired by
- * interrupt_work when dispatching interrupts to individual rings.
- * @pdev: Pointer to the PCI device
- * @iobase: MMIO space of the NHI
- * @tx_rings: All Tx rings available on this host controller
- * @rx_rings: All Rx rings available on this host controller
- * @msix_ida: Used to allocate MSI-X vectors for rings
- * @going_away: The host controller device is about to disappear so when
- * this flag is set, avoid touching the hardware anymore.
- * @interrupt_work: Work scheduled to handle ring interrupt when no
- * MSI-X is used.
- * @hop_count: Number of rings (end point hops) supported by NHI.
- */
-struct tb_nhi {
- struct mutex lock;
- struct pci_dev *pdev;
- void __iomem *iobase;
- struct tb_ring **tx_rings;
- struct tb_ring **rx_rings;
- struct ida msix_ida;
- bool going_away;
- struct work_struct interrupt_work;
- u32 hop_count;
-};
-
-/**
- * struct tb_ring - thunderbolt TX or RX ring associated with a NHI
- * @lock: Lock serializing actions to this ring. Must be acquired after
- * nhi->lock.
- * @nhi: Pointer to the native host controller interface
- * @size: Size of the ring
- * @hop: Hop (DMA channel) associated with this ring
- * @head: Head of the ring (write next descriptor here)
- * @tail: Tail of the ring (complete next descriptor here)
- * @descriptors: Allocated descriptors for this ring
- * @queue: Queue holding frames to be transferred over this ring
- * @in_flight: Queue holding frames that are currently in flight
- * @work: Interrupt work structure
- * @is_tx: Is the ring Tx or Rx
- * @running: Is the ring running
- * @irq: MSI-X irq number if the ring uses MSI-X. %0 otherwise.
- * @vector: MSI-X vector number the ring uses (only set if @irq is > 0)
- * @flags: Ring specific flags
- * @sof_mask: Bit mask used to detect start of frame PDF
- * @eof_mask: Bit mask used to detect end of frame PDF
- */
-struct tb_ring {
- struct mutex lock;
- struct tb_nhi *nhi;
- int size;
- int hop;
- int head;
- int tail;
- struct ring_desc *descriptors;
- dma_addr_t descriptors_dma;
- struct list_head queue;
- struct list_head in_flight;
- struct work_struct work;
- bool is_tx:1;
- bool running:1;
- int irq;
- u8 vector;
- unsigned int flags;
- u16 sof_mask;
- u16 eof_mask;
-};
-
-/* Leave ring interrupt enabled on suspend */
-#define RING_FLAG_NO_SUSPEND BIT(0)
-/* Configure the ring to be in frame mode */
-#define RING_FLAG_FRAME BIT(1)
-/* Enable end-to-end flow control */
-#define RING_FLAG_E2E BIT(2)
-
-struct ring_frame;
-typedef void (*ring_cb)(struct tb_ring*, struct ring_frame*, bool canceled);
-
-/**
- * struct ring_frame - for use with ring_rx/ring_tx
- */
-struct ring_frame {
- dma_addr_t buffer_phy;
- ring_cb callback;
- struct list_head list;
- u32 size:12; /* TX: in, RX: out*/
- u32 flags:12; /* RX: out */
- u32 eof:4; /* TX:in, RX: out */
- u32 sof:4; /* TX:in, RX: out */
-};
-
-#define TB_FRAME_SIZE 0x100 /* minimum size for ring_rx */
-
-struct tb_ring *ring_alloc_tx(struct tb_nhi *nhi, int hop, int size,
- unsigned int flags);
-struct tb_ring *ring_alloc_rx(struct tb_nhi *nhi, int hop, int size,
- unsigned int flags, u16 sof_mask, u16 eof_mask);
-void ring_start(struct tb_ring *ring);
-void ring_stop(struct tb_ring *ring);
-void ring_free(struct tb_ring *ring);
-
-int __ring_enqueue(struct tb_ring *ring, struct ring_frame *frame);
-
-/**
- * ring_rx() - enqueue a frame on an RX ring
- *
- * frame->buffer, frame->buffer_phy and frame->callback have to be set. The
- * buffer must contain at least TB_FRAME_SIZE bytes.
- *
- * frame->callback will be invoked with frame->size, frame->flags, frame->eof,
- * frame->sof set once the frame has been received.
- *
- * If ring_stop is called after the packet has been enqueued frame->callback
- * will be called with canceled set to true.
- *
- * Return: Returns ESHUTDOWN if ring_stop has been called. Zero otherwise.
- */
-static inline int ring_rx(struct tb_ring *ring, struct ring_frame *frame)
-{
- WARN_ON(ring->is_tx);
- return __ring_enqueue(ring, frame);
-}
-
-/**
- * ring_tx() - enqueue a frame on an TX ring
- *
- * frame->buffer, frame->buffer_phy, frame->callback, frame->size, frame->eof
- * and frame->sof have to be set.
- *
- * frame->callback will be invoked with once the frame has been transmitted.
- *
- * If ring_stop is called after the packet has been enqueued frame->callback
- * will be called with canceled set to true.
- *
- * Return: Returns ESHUTDOWN if ring_stop has been called. Zero otherwise.
- */
-static inline int ring_tx(struct tb_ring *ring, struct ring_frame *frame)
-{
- WARN_ON(!ring->is_tx);
- return __ring_enqueue(ring, frame);
-}
+#include <linux/thunderbolt.h>

enum nhi_fw_mode {
NHI_FW_SAFE_MODE,
diff --git a/include/linux/thunderbolt.h b/include/linux/thunderbolt.h
index 79abdaf1c296..1a376374c327 100644
--- a/include/linux/thunderbolt.h
+++ b/include/linux/thunderbolt.h
@@ -15,10 +15,12 @@
#define THUNDERBOLT_H_

#include <linux/device.h>
+#include <linux/idr.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/mod_devicetable.h>
#include <linux/uuid.h>
+#include <linux/workqueue.h>

enum tb_cfg_pkg_type {
TB_CFG_PKG_READ = 1,
@@ -397,4 +399,160 @@ static inline struct tb_xdomain *tb_service_parent(struct tb_service *svc)
return tb_to_xdomain(svc->dev.parent);
}

+/**
+ * struct tb_nhi - thunderbolt native host interface
+ * @lock: Must be held during ring creation/destruction. Is acquired by
+ * interrupt_work when dispatching interrupts to individual rings.
+ * @pdev: Pointer to the PCI device
+ * @iobase: MMIO space of the NHI
+ * @tx_rings: All Tx rings available on this host controller
+ * @rx_rings: All Rx rings available on this host controller
+ * @msix_ida: Used to allocate MSI-X vectors for rings
+ * @going_away: The host controller device is about to disappear so when
+ * this flag is set, avoid touching the hardware anymore.
+ * @interrupt_work: Work scheduled to handle ring interrupt when no
+ * MSI-X is used.
+ * @hop_count: Number of rings (end point hops) supported by NHI.
+ */
+struct tb_nhi {
+ struct mutex lock;
+ struct pci_dev *pdev;
+ void __iomem *iobase;
+ struct tb_ring **tx_rings;
+ struct tb_ring **rx_rings;
+ struct ida msix_ida;
+ bool going_away;
+ struct work_struct interrupt_work;
+ u32 hop_count;
+};
+
+/**
+ * struct tb_ring - thunderbolt TX or RX ring associated with a NHI
+ * @lock: Lock serializing actions to this ring. Must be acquired after
+ * nhi->lock.
+ * @nhi: Pointer to the native host controller interface
+ * @size: Size of the ring
+ * @hop: Hop (DMA channel) associated with this ring
+ * @head: Head of the ring (write next descriptor here)
+ * @tail: Tail of the ring (complete next descriptor here)
+ * @descriptors: Allocated descriptors for this ring
+ * @queue: Queue holding frames to be transferred over this ring
+ * @in_flight: Queue holding frames that are currently in flight
+ * @work: Interrupt work structure
+ * @is_tx: Is the ring Tx or Rx
+ * @running: Is the ring running
+ * @irq: MSI-X irq number if the ring uses MSI-X. %0 otherwise.
+ * @vector: MSI-X vector number the ring uses (only set if @irq is > 0)
+ * @flags: Ring specific flags
+ * @sof_mask: Bit mask used to detect start of frame PDF
+ * @eof_mask: Bit mask used to detect end of frame PDF
+ */
+struct tb_ring {
+ struct mutex lock;
+ struct tb_nhi *nhi;
+ int size;
+ int hop;
+ int head;
+ int tail;
+ struct ring_desc *descriptors;
+ dma_addr_t descriptors_dma;
+ struct list_head queue;
+ struct list_head in_flight;
+ struct work_struct work;
+ bool is_tx:1;
+ bool running:1;
+ int irq;
+ u8 vector;
+ unsigned int flags;
+ u16 sof_mask;
+ u16 eof_mask;
+};
+
+/* Leave ring interrupt enabled on suspend */
+#define RING_FLAG_NO_SUSPEND BIT(0)
+/* Configure the ring to be in frame mode */
+#define RING_FLAG_FRAME BIT(1)
+/* Enable end-to-end flow control */
+#define RING_FLAG_E2E BIT(2)
+
+struct ring_frame;
+typedef void (*ring_cb)(struct tb_ring *, struct ring_frame *, bool canceled);
+
+/**
+ * struct ring_frame - For use with ring_rx/ring_tx
+ * @buffer_phy: DMA mapped address of the frame
+ * @callback: Callback called when the frame is finished
+ * @list: Frame is linked to a queue using this
+ * @size: Size of the frame in bytes (%0 means %4096)
+ * @flags: Flags for the frame (see &enum ring_desc_flags)
+ * @eof: End of frame protocol defined field
+ * @sof: Start of frame protocol defined field
+ */
+struct ring_frame {
+ dma_addr_t buffer_phy;
+ ring_cb callback;
+ struct list_head list;
+ u32 size:12;
+ u32 flags:12;
+ u32 eof:4;
+ u32 sof:4;
+};
+
+/* Minimum size for ring_rx */
+#define TB_FRAME_SIZE 0x100
+
+struct tb_ring *tb_ring_alloc_tx(struct tb_nhi *nhi, int hop, int size,
+ unsigned int flags);
+struct tb_ring *tb_ring_alloc_rx(struct tb_nhi *nhi, int hop, int size,
+ unsigned int flags, u16 sof_mask,
+ u16 eof_mask);
+void tb_ring_start(struct tb_ring *ring);
+void tb_ring_stop(struct tb_ring *ring);
+void tb_ring_free(struct tb_ring *ring);
+
+int __tb_ring_enqueue(struct tb_ring *ring, struct ring_frame *frame);
+
+/**
+ * tb_ring_rx() - enqueue a frame on an RX ring
+ * @ring: Ring to enqueue the frame
+ * @frame: Frame to enqueue
+ *
+ * @frame->buffer, @frame->buffer_phy and @frame->callback have to be set. The
+ * buffer must contain at least %TB_FRAME_SIZE bytes.
+ *
+ * @frame->callback will be invoked with @frame->size, @frame->flags,
+ * @frame->eof, @frame->sof set once the frame has been received.
+ *
+ * If ring_stop() is called after the packet has been enqueued
+ * @frame->callback will be called with canceled set to true.
+ *
+ * Return: Returns %-ESHUTDOWN if ring_stop has been called. Zero otherwise.
+ */
+static inline int tb_ring_rx(struct tb_ring *ring, struct ring_frame *frame)
+{
+ WARN_ON(ring->is_tx);
+ return __tb_ring_enqueue(ring, frame);
+}
+
+/**
+ * tb_ring_tx() - enqueue a frame on an TX ring
+ * @ring: Ring the enqueue the frame
+ * @frame: Frame to enqueue
+ *
+ * @frame->buffer, @frame->buffer_phy, @frame->callback, @frame->size,
+ * @frame->eof and @frame->sof have to be set.
+ *
+ * @frame->callback will be invoked with once the frame has been transmitted.
+ *
+ * If ring_stop() is called after the packet has been enqueued @frame->callback
+ * will be called with canceled set to true.
+ *
+ * Return: Returns %-ESHUTDOWN if ring_stop has been called. Zero otherwise.
+ */
+static inline int tb_ring_tx(struct tb_ring *ring, struct ring_frame *frame)
+{
+ WARN_ON(!ring->is_tx);
+ return __tb_ring_enqueue(ring, frame);
+}
+
#endif /* THUNDERBOLT_H_ */
--
2.13.5