@@ -33,6 +33,25 @@ if DMADEVICES
comment "DMA Devices"
+config INTEL_MIC_X100_DMA
+ tristate "Intel MIC X100 DMA Driver"
+ depends on 64BIT && X86 && INTEL_MIC_BUS
+ select DMAENGINE
+ default N
+ help
+ This enables DMA support for the Intel Many Integrated Core
+ (MIC) family of PCIe form factor coprocessor X100 devices that
+ run a 64 bit Linux OS. This driver will be used by both MIC
+ host and card drivers.
+
+ If you are building host kernel with a MIC device or a card
+ kernel for a MIC device, then say M (recommended) or Y, else
+ say N. If unsure say N.
+
+ More information about the Intel MIC family as well as the Linux
+ OS and tools for MIC to use with this driver are available from
+ <http://software.intel.com/en-us/mic-developer>.
+
config INTEL_MID_DMAC
tristate "Intel MID DMA support for Peripheral DMA controllers"
depends on PCI && X86
@@ -46,3 +46,4 @@ obj-$(CONFIG_K3_DMA) += k3dma.o
obj-$(CONFIG_MOXART_DMA) += moxart-dma.o
obj-$(CONFIG_FSL_EDMA) += fsl-edma.o
obj-$(CONFIG_QCOM_BAM_DMA) += qcom_bam_dma.o
+obj-$(CONFIG_INTEL_MIC_X100_DMA) += mic_x100_dma.o
new file mode 100644
@@ -0,0 +1,774 @@
+/*
+ * Intel MIC Platform Software Stack (MPSS)
+ *
+ * Copyright(c) 2014 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * The full GNU General Public License is included in this distribution in
+ * the file called "COPYING".
+ *
+ * Intel MIC X100 DMA Driver.
+ *
+ * Adapted from IOAT dma driver.
+ */
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/seq_file.h>
+
+#include "mic_x100_dma.h"
+
+#define MIC_DMA_MAX_XFER_SIZE_CARD (1 * 1024 * 1024 -\
+ MIC_DMA_ALIGN_BYTES)
+#define MIC_DMA_MAX_XFER_SIZE_HOST (1 * 1024 * 1024 >> 1)
+#define MIC_DMA_DESC_TYPE_SHIFT 60
+#define MIC_DMA_MEMCPY_LEN_SHIFT 46
+#define MIC_DMA_STAT_INTR_SHIFT 59
+
+/* high-water mark for pushing dma descriptors */
+static int mic_dma_pending_level = 4;
+
+/* Status descriptor is used to write a 64 bit value to a memory location */
+enum mic_dma_desc_format_type {
+ MIC_DMA_MEMCPY = 1,
+ MIC_DMA_STATUS,
+};
+
+static inline u32 mic_dma_hw_ring_inc(u32 val)
+{
+ return (val + 1) % MIC_DMA_DESC_RX_SIZE;
+}
+
+static inline u32 mic_dma_hw_ring_dec(u32 val)
+{
+ return val ? val - 1 : MIC_DMA_DESC_RX_SIZE - 1;
+}
+
+static inline void mic_dma_hw_ring_inc_head(struct mic_dma_chan *ch)
+{
+ ch->head = mic_dma_hw_ring_inc(ch->head);
+}
+
+/* Prepare a memcpy desc */
+static inline void mic_dma_memcpy_desc(struct mic_dma_desc *desc,
+ dma_addr_t src_phys, dma_addr_t dst_phys, u64 size)
+{
+ u64 qw0, qw1;
+
+ qw0 = src_phys;
+ qw0 |= (size >> MIC_DMA_ALIGN_SHIFT) << MIC_DMA_MEMCPY_LEN_SHIFT;
+ qw1 = MIC_DMA_MEMCPY;
+ qw1 <<= MIC_DMA_DESC_TYPE_SHIFT;
+ qw1 |= dst_phys;
+ desc->qw0 = qw0;
+ desc->qw1 = qw1;
+}
+
+/* Prepare a status desc. with @data to be written at @dst_phys */
+static inline void mic_dma_prep_status_desc(struct mic_dma_desc *desc, u64 data,
+ dma_addr_t dst_phys, bool generate_intr)
+{
+ u64 qw0, qw1;
+
+ qw0 = data;
+ qw1 = (u64) MIC_DMA_STATUS << MIC_DMA_DESC_TYPE_SHIFT | dst_phys;
+ if (generate_intr)
+ qw1 |= (1ULL << MIC_DMA_STAT_INTR_SHIFT);
+ desc->qw0 = qw0;
+ desc->qw1 = qw1;
+}
+
+static void mic_dma_cleanup(struct mic_dma_chan *ch)
+{
+ struct dma_async_tx_descriptor *tx;
+ u32 tail;
+ u32 last_tail;
+
+ spin_lock(&ch->cleanup_lock);
+ tail = mic_dma_read_cmp_cnt(ch);
+ /*
+ * This is the barrier pair for smp_wmb() in fn.
+ * mic_dma_tx_submit_unlock. It's required so that we read the
+ * updated cookie value from tx->cookie.
+ */
+ smp_rmb();
+ for (last_tail = ch->last_tail; tail != last_tail;) {
+ tx = &ch->tx_array[last_tail];
+ if (tx->cookie) {
+ dma_cookie_complete(tx);
+ if (tx->callback) {
+ tx->callback(tx->callback_param);
+ tx->callback = NULL;
+ }
+ }
+ last_tail = mic_dma_hw_ring_inc(last_tail);
+ }
+ /* finish all completion callbacks before incrementing tail */
+ smp_mb();
+ ch->last_tail = last_tail;
+ spin_unlock(&ch->cleanup_lock);
+}
+
+static u32 mic_dma_ring_count(u32 head, u32 tail)
+{
+ u32 count;
+
+ if (head >= tail)
+ count = (tail - 0) + (MIC_DMA_DESC_RX_SIZE - head);
+ else
+ count = tail - head;
+ return count - 1;
+}
+
+/* Returns the num. of free descriptors on success, -ENOMEM on failure */
+static int mic_dma_avail_desc_ring_space(struct mic_dma_chan *ch, int required)
+{
+ struct device *dev = mic_dma_ch_to_device(ch);
+ u32 count;
+
+ count = mic_dma_ring_count(ch->head, ch->last_tail);
+ if (count < required) {
+ mic_dma_cleanup(ch);
+ count = mic_dma_ring_count(ch->head, ch->last_tail);
+ }
+
+ if (count < required) {
+ dev_dbg(dev, "Not enough desc space");
+ dev_dbg(dev, "%s %d required=%u, avail=%u\n",
+ __func__, __LINE__, required, count);
+ return -ENOMEM;
+ } else {
+ return count;
+ }
+}
+
+/* Program memcpy descriptors into the descriptor ring and update s/w head ptr*/
+static int mic_dma_prog_memcpy_desc(struct mic_dma_chan *ch, dma_addr_t src,
+ dma_addr_t dst, size_t len)
+{
+ size_t current_transfer_len;
+ size_t max_xfer_size = to_mic_dma_dev(ch)->max_xfer_size;
+ /* 3 is added to make sure we have enough space for status desc */
+ int num_desc = len / max_xfer_size + 3;
+ int ret;
+
+ if (len % max_xfer_size)
+ num_desc++;
+
+ ret = mic_dma_avail_desc_ring_space(ch, num_desc);
+ if (ret < 0)
+ return ret;
+ do {
+ current_transfer_len = min(len, max_xfer_size);
+ mic_dma_memcpy_desc(&ch->desc_ring[ch->head],
+ src, dst, current_transfer_len);
+ mic_dma_hw_ring_inc_head(ch);
+ len -= current_transfer_len;
+ dst = dst + current_transfer_len;
+ src = src + current_transfer_len;
+ } while (len > 0);
+ return 0;
+}
+
+/* It's a h/w quirk and h/w needs 2 status descriptors for every status desc */
+static void mic_dma_prog_intr(struct mic_dma_chan *ch)
+{
+ mic_dma_prep_status_desc(&ch->desc_ring[ch->head], 0,
+ ch->status_dest_micpa, false);
+ mic_dma_hw_ring_inc_head(ch);
+ mic_dma_prep_status_desc(&ch->desc_ring[ch->head], 0,
+ ch->status_dest_micpa, true);
+ mic_dma_hw_ring_inc_head(ch);
+}
+
+/* Wrapper function to program memcpy descriptors/status descriptors */
+static int mic_dma_do_dma(struct mic_dma_chan *ch, int flags, dma_addr_t src,
+ dma_addr_t dst, size_t len)
+{
+ if (-ENOMEM == mic_dma_prog_memcpy_desc(ch, src, dst, len))
+ return -ENOMEM;
+ /* Above mic_dma_prog_memcpy_desc() makes sure we have enough space */
+ if (flags & DMA_PREP_FENCE) {
+ mic_dma_prep_status_desc(&ch->desc_ring[ch->head], 0,
+ ch->status_dest_micpa, false);
+ mic_dma_hw_ring_inc_head(ch);
+ }
+
+ if (flags & DMA_PREP_INTERRUPT)
+ mic_dma_prog_intr(ch);
+
+ return 0;
+}
+
+static inline void mic_dma_issue_pending(struct dma_chan *ch)
+{
+ struct mic_dma_chan *mic_ch = to_mic_dma_chan(ch);
+
+ spin_lock(&mic_ch->issue_lock);
+ /*
+ * Write to head triggers h/w to act on the descriptors.
+ * On MIC, writing the same head value twice causes
+ * a h/w error. On second write, h/w assumes we filled
+ * the entire ring & overwrote some of the descriptors.
+ */
+ if (mic_ch->issued == mic_ch->submitted)
+ goto out;
+ mic_ch->issued = mic_ch->submitted;
+ /*
+ * make descriptor updates visible before advancing head,
+ * this is purposefully not smp_wmb() since we are also
+ * publishing the descriptor updates to a dma device
+ */
+ wmb();
+ mic_dma_write_reg(mic_ch, MIC_DMA_REG_DHPR, mic_ch->issued);
+out:
+ spin_unlock(&mic_ch->issue_lock);
+}
+
+static inline void mic_dma_update_pending(struct mic_dma_chan *ch)
+{
+ if (mic_dma_ring_count(ch->issued, ch->submitted)
+ > mic_dma_pending_level)
+ mic_dma_issue_pending(&ch->api_ch);
+}
+
+static dma_cookie_t mic_dma_tx_submit_unlock(struct dma_async_tx_descriptor *tx)
+{
+ struct mic_dma_chan *mic_ch = to_mic_dma_chan(tx->chan);
+ dma_cookie_t cookie;
+
+ dma_cookie_assign(tx);
+ cookie = tx->cookie;
+ /*
+ * We need an smp write barrier here because another CPU might see
+ * an update to submitted and update h/w head even before we
+ * assigned a cookie to this tx.
+ */
+ smp_wmb();
+ mic_ch->submitted = mic_ch->head;
+ spin_unlock(&mic_ch->prep_lock);
+ mic_dma_update_pending(mic_ch);
+ return cookie;
+}
+
+static inline struct dma_async_tx_descriptor *
+allocate_tx(struct mic_dma_chan *ch)
+{
+ u32 idx = mic_dma_hw_ring_dec(ch->head);
+ struct dma_async_tx_descriptor *tx = &ch->tx_array[idx];
+
+ dma_async_tx_descriptor_init(tx, &ch->api_ch);
+ tx->tx_submit = mic_dma_tx_submit_unlock;
+ return tx;
+}
+
+/*
+ * Prepare a memcpy descriptor to be added to the ring.
+ * Note that the temporary descriptor adds an extra overhead of copying the
+ * descriptor to ring. So, we copy directly to the descriptor ring
+ */
+static struct dma_async_tx_descriptor *
+mic_dma_prep_memcpy_lock(struct dma_chan *ch, dma_addr_t dma_dest,
+ dma_addr_t dma_src, size_t len, unsigned long flags)
+{
+ struct mic_dma_chan *mic_ch = to_mic_dma_chan(ch);
+ struct device *dev = mic_dma_ch_to_device(mic_ch);
+ int result;
+
+ if (!len && !flags)
+ return NULL;
+
+ spin_lock(&mic_ch->prep_lock);
+ result = mic_dma_do_dma(mic_ch, flags, dma_src, dma_dest, len);
+ if (result >= 0)
+ return allocate_tx(mic_ch);
+ dev_err(dev, "Error enqueueing dma, error=%d\n", result);
+ spin_unlock(&mic_ch->prep_lock);
+ return NULL;
+}
+
+static struct dma_async_tx_descriptor *
+mic_dma_prep_interrupt_lock(struct dma_chan *ch, unsigned long flags)
+{
+ struct mic_dma_chan *mic_ch = to_mic_dma_chan(ch);
+ int ret;
+
+ spin_lock(&mic_ch->prep_lock);
+ ret = mic_dma_do_dma(mic_ch, flags, 0, 0, 0);
+ if (!ret)
+ return allocate_tx(mic_ch);
+ spin_unlock(&mic_ch->prep_lock);
+ return NULL;
+}
+
+/* Return the status of the transaction */
+static enum dma_status
+mic_dma_tx_status(struct dma_chan *ch, dma_cookie_t cookie,
+ struct dma_tx_state *txstate)
+{
+ struct mic_dma_chan *mic_ch = to_mic_dma_chan(ch);
+
+ if (DMA_COMPLETE != dma_cookie_status(ch, cookie, txstate))
+ mic_dma_cleanup(mic_ch);
+
+ return dma_cookie_status(ch, cookie, txstate);
+}
+
+static irqreturn_t mic_dma_thread_fn(int irq, void *data)
+{
+ mic_dma_cleanup((struct mic_dma_chan *)data);
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t mic_dma_intr_handler(int irq, void *data)
+{
+ struct mic_dma_chan *ch = ((struct mic_dma_chan *)data);
+
+ mic_dma_ack_interrupt(ch);
+ return IRQ_WAKE_THREAD;
+}
+
+static int mic_dma_alloc_desc_ring(struct mic_dma_chan *ch)
+{
+ u64 desc_ring_size = MIC_DMA_DESC_RX_SIZE * sizeof(*ch->desc_ring);
+ struct device *dev = &to_mbus_device(ch)->dev;
+
+ desc_ring_size = ALIGN(desc_ring_size, MIC_DMA_ALIGN_BYTES);
+ ch->desc_ring = kzalloc(desc_ring_size, GFP_KERNEL);
+
+ if (!ch->desc_ring)
+ return -ENOMEM;
+
+ ch->desc_ring_micpa = dma_map_single(dev, ch->desc_ring,
+ desc_ring_size, DMA_BIDIRECTIONAL);
+ if (dma_mapping_error(dev, ch->desc_ring_micpa))
+ goto map_error;
+
+ ch->tx_array = vzalloc(MIC_DMA_DESC_RX_SIZE * sizeof(*ch->tx_array));
+ if (!ch->tx_array)
+ goto tx_error;
+ return 0;
+tx_error:
+ dma_unmap_single(dev, ch->desc_ring_micpa, desc_ring_size,
+ DMA_BIDIRECTIONAL);
+map_error:
+ kfree(ch->desc_ring);
+ return -ENOMEM;
+}
+
+static void mic_dma_free_desc_ring(struct mic_dma_chan *ch)
+{
+ u64 desc_ring_size = MIC_DMA_DESC_RX_SIZE * sizeof(*ch->desc_ring);
+
+ vfree(ch->tx_array);
+ desc_ring_size = ALIGN(desc_ring_size, MIC_DMA_ALIGN_BYTES);
+ dma_unmap_single(&to_mbus_device(ch)->dev, ch->desc_ring_micpa,
+ desc_ring_size, DMA_BIDIRECTIONAL);
+ kfree(ch->desc_ring);
+ ch->desc_ring = NULL;
+}
+
+static void mic_dma_free_status_dest(struct mic_dma_chan *ch)
+{
+ dma_unmap_single(&to_mbus_device(ch)->dev, ch->status_dest_micpa,
+ L1_CACHE_BYTES, DMA_BIDIRECTIONAL);
+ kfree(ch->status_dest);
+}
+
+static int mic_dma_alloc_status_dest(struct mic_dma_chan *ch)
+{
+ struct device *dev = &to_mbus_device(ch)->dev;
+
+ ch->status_dest = kzalloc(L1_CACHE_BYTES, GFP_KERNEL);
+ if (!ch->status_dest)
+ return -ENOMEM;
+ ch->status_dest_micpa = dma_map_single(dev, ch->status_dest,
+ L1_CACHE_BYTES, DMA_BIDIRECTIONAL);
+ if (dma_mapping_error(dev, ch->status_dest_micpa)) {
+ kfree(ch->status_dest);
+ ch->status_dest = NULL;
+ return -ENOMEM;
+ }
+ return 0;
+}
+
+static int mic_dma_check_chan(struct mic_dma_chan *ch)
+{
+ if (mic_dma_read_reg(ch, MIC_DMA_REG_DCHERR) ||
+ mic_dma_read_reg(ch, MIC_DMA_REG_DSTAT) & MIC_DMA_CHAN_QUIESCE) {
+ mic_dma_disable_chan(ch);
+ mic_dma_chan_mask_intr(ch);
+ dev_err(mic_dma_ch_to_device(ch),
+ "%s %d error setting up mic dma chan %d\n",
+ __func__, __LINE__, ch->ch_num);
+ return -EBUSY;
+ }
+ return 0;
+}
+
+static int mic_dma_chan_setup(struct mic_dma_chan *ch)
+{
+ if (MIC_DMA_CHAN_MIC == ch->owner)
+ mic_dma_chan_set_owner(ch);
+ mic_dma_disable_chan(ch);
+ mic_dma_chan_mask_intr(ch);
+ mic_dma_write_reg(ch, MIC_DMA_REG_DCHERRMSK, 0);
+ mic_dma_chan_set_desc_ring(ch);
+ ch->last_tail = mic_dma_read_reg(ch, MIC_DMA_REG_DTPR);
+ ch->head = ch->last_tail;
+ ch->issued = 0;
+ mic_dma_chan_unmask_intr(ch);
+ mic_dma_enable_chan(ch);
+ return mic_dma_check_chan(ch);
+}
+
+static void mic_dma_chan_destroy(struct mic_dma_chan *ch)
+{
+ mic_dma_disable_chan(ch);
+ mic_dma_chan_mask_intr(ch);
+}
+
+static void mic_dma_unregister_dma_device(struct mic_dma_device *mic_dma_dev)
+{
+ dma_async_device_unregister(&mic_dma_dev->dma_dev);
+}
+
+static int mic_dma_setup_irq(struct mic_dma_chan *ch)
+{
+ ch->cookie =
+ to_mbus_hw_ops(ch)->request_threaded_irq(to_mbus_device(ch),
+ mic_dma_intr_handler, mic_dma_thread_fn,
+ "mic dma_channel", ch, ch->ch_num);
+ if (IS_ERR(ch->cookie))
+ return IS_ERR(ch->cookie);
+ return 0;
+}
+
+static inline void mic_dma_free_irq(struct mic_dma_chan *ch)
+{
+ to_mbus_hw_ops(ch)->free_irq(to_mbus_device(ch), ch->cookie, ch);
+}
+
+static int mic_dma_chan_init(struct mic_dma_chan *ch)
+{
+ int ret = mic_dma_alloc_desc_ring(ch);
+
+ if (ret)
+ goto ring_error;
+ ret = mic_dma_alloc_status_dest(ch);
+ if (ret)
+ goto status_error;
+ ret = mic_dma_chan_setup(ch);
+ if (ret)
+ goto chan_error;
+ return ret;
+chan_error:
+ mic_dma_free_status_dest(ch);
+status_error:
+ mic_dma_free_desc_ring(ch);
+ring_error:
+ return ret;
+}
+
+static int mic_dma_drain_chan(struct mic_dma_chan *ch)
+{
+ struct dma_async_tx_descriptor *tx;
+ int err = 0;
+ dma_cookie_t cookie;
+
+ tx = mic_dma_prep_memcpy_lock(&ch->api_ch, 0, 0, 0, DMA_PREP_FENCE);
+ if (!tx) {
+ err = -ENOMEM;
+ goto error;
+ }
+
+ cookie = tx->tx_submit(tx);
+ if (dma_submit_error(cookie))
+ err = -ENOMEM;
+ else
+ err = dma_sync_wait(&ch->api_ch, cookie);
+ if (err) {
+ dev_err(mic_dma_ch_to_device(ch), "%s %d TO chan 0x%x\n",
+ __func__, __LINE__, ch->ch_num);
+ err = -EIO;
+ }
+error:
+ mic_dma_cleanup(ch);
+ return err;
+}
+
+static inline void mic_dma_chan_uninit(struct mic_dma_chan *ch)
+{
+ mic_dma_chan_destroy(ch);
+ mic_dma_cleanup(ch);
+ mic_dma_free_status_dest(ch);
+ mic_dma_free_desc_ring(ch);
+}
+
+static int mic_dma_init(struct mic_dma_device *mic_dma_dev,
+ enum mic_dma_chan_owner owner)
+{
+ int i, first_chan = mic_dma_dev->start_ch;
+ struct mic_dma_chan *ch;
+ int ret;
+
+ for (i = first_chan; i < first_chan + MIC_DMA_NUM_CHAN; i++) {
+ unsigned long data;
+ ch = &mic_dma_dev->mic_ch[i];
+ data = (unsigned long)ch;
+ ch->ch_num = i;
+ ch->owner = owner;
+ spin_lock_init(&ch->cleanup_lock);
+ spin_lock_init(&ch->prep_lock);
+ spin_lock_init(&ch->issue_lock);
+ ret = mic_dma_setup_irq(ch);
+ if (ret)
+ goto error;
+ }
+ return 0;
+error:
+ for (i = i - 1; i >= first_chan; i--)
+ mic_dma_free_irq(ch);
+ return ret;
+}
+
+static void mic_dma_uninit(struct mic_dma_device *mic_dma_dev)
+{
+ int i, first_chan = mic_dma_dev->start_ch;
+ struct mic_dma_chan *ch;
+
+ for (i = first_chan; i < first_chan + MIC_DMA_NUM_CHAN; i++) {
+ ch = &mic_dma_dev->mic_ch[i];
+ mic_dma_free_irq(ch);
+ }
+}
+
+static int mic_dma_alloc_chan_resources(struct dma_chan *ch)
+{
+ int ret = mic_dma_chan_init(to_mic_dma_chan(ch));
+ if (ret)
+ return ret;
+ return MIC_DMA_DESC_RX_SIZE;
+}
+
+static void mic_dma_free_chan_resources(struct dma_chan *ch)
+{
+ struct mic_dma_chan *mic_ch = to_mic_dma_chan(ch);
+ mic_dma_drain_chan(mic_ch);
+ mic_dma_chan_uninit(mic_ch);
+}
+
+/* Set the fn. handlers and register the dma device with dma api */
+static int mic_dma_register_dma_device(struct mic_dma_device *mic_dma_dev,
+ enum mic_dma_chan_owner owner)
+{
+ int i, first_chan = mic_dma_dev->start_ch;
+
+ dma_cap_zero(mic_dma_dev->dma_dev.cap_mask);
+ /*
+ * This dma engine is not capable of host memory to host memory
+ * transfers
+ */
+ dma_cap_set(DMA_MEMCPY, mic_dma_dev->dma_dev.cap_mask);
+
+ if (MIC_DMA_CHAN_HOST == owner)
+ dma_cap_set(DMA_PRIVATE, mic_dma_dev->dma_dev.cap_mask);
+ mic_dma_dev->dma_dev.device_alloc_chan_resources =
+ mic_dma_alloc_chan_resources;
+ mic_dma_dev->dma_dev.device_free_chan_resources =
+ mic_dma_free_chan_resources;
+ mic_dma_dev->dma_dev.device_tx_status = mic_dma_tx_status;
+ mic_dma_dev->dma_dev.device_prep_dma_memcpy = mic_dma_prep_memcpy_lock;
+ mic_dma_dev->dma_dev.device_prep_dma_interrupt =
+ mic_dma_prep_interrupt_lock;
+ mic_dma_dev->dma_dev.device_issue_pending = mic_dma_issue_pending;
+ mic_dma_dev->dma_dev.copy_align = MIC_DMA_ALIGN_SHIFT;
+ INIT_LIST_HEAD(&mic_dma_dev->dma_dev.channels);
+ for (i = first_chan; i < first_chan + MIC_DMA_NUM_CHAN; i++) {
+ mic_dma_dev->mic_ch[i].api_ch.device = &mic_dma_dev->dma_dev;
+ dma_cookie_init(&mic_dma_dev->mic_ch[i].api_ch);
+ list_add_tail(&mic_dma_dev->mic_ch[i].api_ch.device_node,
+ &mic_dma_dev->dma_dev.channels);
+ }
+ return dma_async_device_register(&mic_dma_dev->dma_dev);
+}
+
+/*
+ * Initializes dma channels and registers the dma device with the
+ * dma engine api.
+ */
+static struct mic_dma_device *mic_dma_dev_reg(struct mbus_device *mbdev,
+ enum mic_dma_chan_owner owner)
+{
+ struct mic_dma_device *mic_dma_dev;
+ int ret;
+ struct device *dev = &mbdev->dev;
+
+ mic_dma_dev = kzalloc(sizeof(*mic_dma_dev), GFP_KERNEL);
+ if (!mic_dma_dev) {
+ ret = -ENOMEM;
+ goto alloc_error;
+ }
+ mic_dma_dev->mbdev = mbdev;
+ mic_dma_dev->dma_dev.dev = dev;
+ mic_dma_dev->mmio = mbdev->mmio_va;
+ if (MIC_DMA_CHAN_HOST == owner) {
+ mic_dma_dev->start_ch = 0;
+ mic_dma_dev->max_xfer_size = MIC_DMA_MAX_XFER_SIZE_HOST;
+ } else {
+ mic_dma_dev->start_ch = 4;
+ mic_dma_dev->max_xfer_size = MIC_DMA_MAX_XFER_SIZE_CARD;
+ }
+ ret = mic_dma_init(mic_dma_dev, owner);
+ if (ret)
+ goto init_error;
+ ret = mic_dma_register_dma_device(mic_dma_dev, owner);
+ if (ret)
+ goto reg_error;
+ return mic_dma_dev;
+reg_error:
+ mic_dma_uninit(mic_dma_dev);
+init_error:
+ kfree(mic_dma_dev);
+ mic_dma_dev = NULL;
+alloc_error:
+ dev_err(dev, "Error at %s %d ret=%d\n", __func__, __LINE__, ret);
+ return mic_dma_dev;
+}
+
+static void mic_dma_dev_unreg(struct mic_dma_device *mic_dma_dev)
+{
+ mic_dma_unregister_dma_device(mic_dma_dev);
+ mic_dma_uninit(mic_dma_dev);
+ kfree(mic_dma_dev);
+}
+
+/* DEBUGFS CODE */
+static int mic_dma_reg_seq_show(struct seq_file *s, void *pos)
+{
+ struct mic_dma_device *mic_dma_dev = s->private;
+ int i, chan_num, first_chan = mic_dma_dev->start_ch;
+ struct mic_dma_chan *ch;
+
+ seq_printf(s, "SBOX_DCR: %#x\n",
+ mic_dma_mmio_read(&mic_dma_dev->mic_ch[first_chan],
+ MIC_DMA_SBOX_BASE + MIC_DMA_SBOX_DCR));
+ seq_puts(s, "DMA Channel Registers\n");
+ seq_printf(s, "%-10s| %-10s %-10s %-10s %-10s %-10s",
+ "Channel", "DCAR", "DTPR", "DHPR", "DRAR_HI", "DRAR_LO");
+ seq_printf(s, " %-11s %-14s %-10s\n", "DCHERR", "DCHERRMSK", "DSTAT");
+ for (i = first_chan; i < first_chan + MIC_DMA_NUM_CHAN; i++) {
+ ch = &mic_dma_dev->mic_ch[i];
+ chan_num = ch->ch_num;
+ seq_printf(s, "%-10i| %-#10x %-#10x %-#10x %-#10x",
+ chan_num,
+ mic_dma_read_reg(ch, MIC_DMA_REG_DCAR),
+ mic_dma_read_reg(ch, MIC_DMA_REG_DTPR),
+ mic_dma_read_reg(ch, MIC_DMA_REG_DHPR),
+ mic_dma_read_reg(ch, MIC_DMA_REG_DRAR_HI));
+ seq_printf(s, " %-#10x %-#10x %-#14x %-#10x\n",
+ mic_dma_read_reg(ch, MIC_DMA_REG_DRAR_LO),
+ mic_dma_read_reg(ch, MIC_DMA_REG_DCHERR),
+ mic_dma_read_reg(ch, MIC_DMA_REG_DCHERRMSK),
+ mic_dma_read_reg(ch, MIC_DMA_REG_DSTAT));
+ }
+ return 0;
+}
+
+static int mic_dma_reg_debug_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, mic_dma_reg_seq_show, inode->i_private);
+}
+
+static int mic_dma_reg_debug_release(struct inode *inode, struct file *file)
+{
+ return single_release(inode, file);
+}
+
+static const struct file_operations mic_dma_reg_ops = {
+ .owner = THIS_MODULE,
+ .open = mic_dma_reg_debug_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = mic_dma_reg_debug_release
+};
+
+/* Debugfs parent dir */
+static struct dentry *mic_dma_dbg;
+
+static int mic_dma_driver_probe(struct mbus_device *mbdev)
+{
+ struct mic_dma_device *mic_dma_dev;
+ enum mic_dma_chan_owner owner;
+
+ if (MBUS_DEV_DMA_MIC == mbdev->id.device)
+ owner = MIC_DMA_CHAN_MIC;
+ else
+ owner = MIC_DMA_CHAN_HOST;
+
+ mic_dma_dev = mic_dma_dev_reg(mbdev, owner);
+ mbdev->priv = mic_dma_dev;
+
+ if (mic_dma_dbg) {
+ mic_dma_dev->dbg_dir = debugfs_create_dir(dev_name(&mbdev->dev),
+ mic_dma_dbg);
+ if (mic_dma_dev->dbg_dir)
+ debugfs_create_file("mic_dma_reg", 0444,
+ mic_dma_dev->dbg_dir, mic_dma_dev,
+ &mic_dma_reg_ops);
+ }
+ return 0;
+}
+
+static void mic_dma_driver_remove(struct mbus_device *mbdev)
+{
+ struct mic_dma_device *mic_dma_dev;
+
+ mic_dma_dev = (struct mic_dma_device *)mbdev->priv;
+ debugfs_remove_recursive(mic_dma_dev->dbg_dir);
+ mic_dma_dev_unreg(mic_dma_dev);
+}
+
+static struct mbus_device_id id_table[] = {
+ {MBUS_DEV_DMA_MIC, MBUS_DEV_ANY_ID},
+ {MBUS_DEV_DMA_HOST, MBUS_DEV_ANY_ID},
+ {0},
+};
+
+static struct mbus_driver mic_dma_driver = {
+ .driver.name = KBUILD_MODNAME,
+ .driver.owner = THIS_MODULE,
+ .id_table = id_table,
+ .probe = mic_dma_driver_probe,
+ .remove = mic_dma_driver_remove,
+};
+
+static int __init mic_x100_dma_init(void)
+{
+ int rc = mbus_register_driver(&mic_dma_driver);
+ if (rc)
+ return rc;
+ mic_dma_dbg = debugfs_create_dir(KBUILD_MODNAME, NULL);
+ return 0;
+}
+
+static void __exit mic_x100_dma_exit(void)
+{
+ debugfs_remove_recursive(mic_dma_dbg);
+ mbus_unregister_driver(&mic_dma_driver);
+}
+
+module_init(mic_x100_dma_init);
+module_exit(mic_x100_dma_exit);
+
+MODULE_DEVICE_TABLE(mbus, id_table);
+MODULE_AUTHOR("Intel Corporation");
+MODULE_DESCRIPTION("Intel(R) MIC X100 DMA Driver");
+MODULE_LICENSE("GPL v2");
new file mode 100644
@@ -0,0 +1,286 @@
+/*
+ * Intel MIC Platform Software Stack (MPSS)
+ *
+ * Copyright(c) 2014 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * The full GNU General Public License is included in this distribution in
+ * the file called "COPYING".
+ *
+ * Intel MIC X100 DMA Driver.
+ *
+ * Adapted from IOAT dma driver.
+ */
+#ifndef _MIC_X100_DMA_H_
+#define _MIC_X100_DMA_H_
+
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/sched.h>
+#include <linux/debugfs.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/mic_bus.h>
+
+#include "dmaengine.h"
+
+/*
+ * MIC has a total of 8 dma channels.
+ * Four channels are assigned for host SW use & the remaining for MIC SW.
+ * MIC DMA transfer size & addresses need to be 64 byte aligned.
+ */
+#define MIC_DMA_MAX_NUM_CHAN 8
+#define MIC_DMA_NUM_CHAN 4
+#define MIC_DMA_ALIGN_SHIFT 6
+#define MIC_DMA_ALIGN_BYTES (1 << MIC_DMA_ALIGN_SHIFT)
+#define MIC_DMA_DESC_RX_SIZE (128 * 1024 - 4)
+
+/*
+ * Register descriptions
+ * All the registers are 32 bit registers.
+ * DCR is a global register and all others are per-channel.
+ * DCR - bits 0, 2, 4, 6, 8, 10, 12, 14 - enable bits for channels 0 to 7
+ * bits 1, 3, 5, 7, 9, 11, 13, 15 - owner bits for channels 0 to 7
+ * DCAR - bit 24 & 25 interrupt masks for mic owned & host owned channels
+ * DHPR - head of the descriptor ring updated by s/w
+ * DTPR - tail of the descriptor ring updated by h/w
+ * DRAR_LO - lower 32 bits of descriptor ring's mic address
+ * DRAR_HI - 3:0 - remaining 4 bits of descriptor ring's mic address
+ * 20:4 descriptor ring size
+ * 25:21 mic smpt entry number
+ * DSTAT - 16:0 h/w completion count; 31:28 dma engine status
+ * DCHERR - this register is non-zero on error
+ * DCHERRMSK - interrupt mask register
+ */
+#define MIC_DMA_HW_CMP_CNT_MASK 0x1ffff
+#define MIC_DMA_CHAN_QUIESCE 0x20000000
+#define MIC_DMA_SBOX_BASE 0x00010000
+#define MIC_DMA_SBOX_DCR 0x0000A280
+#define MIC_DMA_SBOX_CH_BASE 0x0001A000
+#define MIC_DMA_SBOX_CHAN_OFF 0x40
+#define MIC_DMA_SBOX_DCAR_IM0 (0x1 << 24)
+#define MIC_DMA_SBOX_DCAR_IM1 (0x1 << 25)
+#define MIC_DMA_SBOX_DRARHI_SYS_MASK (0x1 << 26)
+#define MIC_DMA_REG_DCAR 0
+#define MIC_DMA_REG_DHPR 4
+#define MIC_DMA_REG_DTPR 8
+#define MIC_DMA_REG_DRAR_LO 20
+#define MIC_DMA_REG_DRAR_HI 24
+#define MIC_DMA_REG_DSTAT 32
+#define MIC_DMA_REG_DCHERR 44
+#define MIC_DMA_REG_DCHERRMSK 48
+
+/* HW dma desc */
+struct mic_dma_desc {
+ u64 qw0;
+ u64 qw1;
+};
+
+enum mic_dma_chan_owner {
+ MIC_DMA_CHAN_MIC = 0,
+ MIC_DMA_CHAN_HOST
+};
+
+/*
+ * mic_dma_chan - channel specific information
+ * @ch_num: channel number
+ * @owner: owner of this channel
+ * @last_tail: cached value of descriptor ring tail
+ * @head: index of next descriptor in desc_ring
+ * @issued: hardware notification point
+ * @submitted: index that will be used to submit descriptors to h/w
+ * @api_ch: dma engine api channel
+ * @desc_ring: dma descriptor ring
+ * @desc_ring_micpa: mic physical address of desc_ring
+ * @status_dest: destination for status (fence) descriptor
+ * @status_dest_micpa: mic address for status_dest,
+ * DMA controller uses this address
+ * @tx_array: array of async_tx
+ * @cleanup_lock: lock held when processing completed tx
+ * @prep_lock: lock held in prep_memcpy & released in tx_submit
+ * @issue_lock: lock used to synchronize writes to head
+ * @cookie: mic_irq cookie used with mic irq request
+ */
+struct mic_dma_chan {
+ int ch_num;
+ enum mic_dma_chan_owner owner;
+ u32 last_tail;
+ u32 head;
+ u32 issued;
+ u32 submitted;
+ struct dma_chan api_ch;
+ struct mic_dma_desc *desc_ring;
+ dma_addr_t desc_ring_micpa;
+ u64 *status_dest;
+ dma_addr_t status_dest_micpa;
+ struct dma_async_tx_descriptor *tx_array;
+ spinlock_t cleanup_lock;
+ spinlock_t prep_lock;
+ spinlock_t issue_lock;
+ struct mic_irq *cookie;
+};
+
+/*
+ * struct mic_dma_device - per mic device
+ * @mic_ch: dma channels
+ * @dma_dev: underlying dma device
+ * @mbdev: mic bus dma device
+ * @mmio: virtual address of the mmio space
+ * @dbg_dir: debugfs directory
+ * @start_ch: first channel number that can be used
+ * @max_xfer_size: maximum transfer size per dma descriptor
+ */
+struct mic_dma_device {
+ struct mic_dma_chan mic_ch[MIC_DMA_MAX_NUM_CHAN];
+ struct dma_device dma_dev;
+ struct mbus_device *mbdev;
+ void __iomem *mmio;
+ struct dentry *dbg_dir;
+ int start_ch;
+ size_t max_xfer_size;
+};
+
+static inline struct mic_dma_chan *to_mic_dma_chan(struct dma_chan *ch)
+{
+ return container_of(ch, struct mic_dma_chan, api_ch);
+}
+
+static inline struct mic_dma_device *to_mic_dma_dev(struct mic_dma_chan *ch)
+{
+ return
+ container_of((const typeof(((struct mic_dma_device *)0)->mic_ch)*)
+ (ch - ch->ch_num), struct mic_dma_device, mic_ch);
+}
+
+static inline struct mbus_device *to_mbus_device(struct mic_dma_chan *ch)
+{
+ return to_mic_dma_dev(ch)->mbdev;
+}
+
+static inline struct mbus_hw_ops *to_mbus_hw_ops(struct mic_dma_chan *ch)
+{
+ return to_mbus_device(ch)->hw_ops;
+}
+
+static inline struct device *mic_dma_ch_to_device(struct mic_dma_chan *ch)
+{
+ return to_mic_dma_dev(ch)->dma_dev.dev;
+}
+
+static inline void __iomem *mic_dma_chan_to_mmio(struct mic_dma_chan *ch)
+{
+ return to_mic_dma_dev(ch)->mmio;
+}
+
+static inline u32 mic_dma_read_reg(struct mic_dma_chan *ch, u32 reg)
+{
+ return ioread32(mic_dma_chan_to_mmio(ch) + MIC_DMA_SBOX_CH_BASE +
+ ch->ch_num * MIC_DMA_SBOX_CHAN_OFF + reg);
+}
+
+static inline void mic_dma_write_reg(struct mic_dma_chan *ch, u32 reg, u32 val)
+{
+ iowrite32(val, mic_dma_chan_to_mmio(ch) + MIC_DMA_SBOX_CH_BASE +
+ ch->ch_num * MIC_DMA_SBOX_CHAN_OFF + reg);
+}
+
+static inline u32 mic_dma_mmio_read(struct mic_dma_chan *ch, u32 offset)
+{
+ return ioread32(mic_dma_chan_to_mmio(ch) + offset);
+}
+
+static inline void mic_dma_mmio_write(struct mic_dma_chan *ch, u32 val,
+ u32 offset)
+{
+ iowrite32(val, mic_dma_chan_to_mmio(ch) + offset);
+}
+
+static inline u32 mic_dma_read_cmp_cnt(struct mic_dma_chan *ch)
+{
+ return mic_dma_read_reg(ch, MIC_DMA_REG_DSTAT) &
+ MIC_DMA_HW_CMP_CNT_MASK;
+}
+
+static inline void mic_dma_chan_set_owner(struct mic_dma_chan *ch)
+{
+ u32 dcr = mic_dma_mmio_read(ch, MIC_DMA_SBOX_BASE + MIC_DMA_SBOX_DCR);
+ u32 chan_num = ch->ch_num;
+
+ dcr = (dcr & ~(0x1 << (chan_num * 2))) | (ch->owner << (chan_num * 2));
+ mic_dma_mmio_write(ch, dcr, MIC_DMA_SBOX_BASE + MIC_DMA_SBOX_DCR);
+}
+
+static inline void mic_dma_enable_chan(struct mic_dma_chan *ch)
+{
+ u32 dcr = mic_dma_mmio_read(ch, MIC_DMA_SBOX_BASE + MIC_DMA_SBOX_DCR);
+
+ dcr |= 2 << (ch->ch_num << 1);
+ mic_dma_mmio_write(ch, dcr, MIC_DMA_SBOX_BASE + MIC_DMA_SBOX_DCR);
+}
+
+static inline void mic_dma_disable_chan(struct mic_dma_chan *ch)
+{
+ u32 dcr = mic_dma_mmio_read(ch, MIC_DMA_SBOX_BASE + MIC_DMA_SBOX_DCR);
+
+ dcr &= ~(2 << (ch->ch_num << 1));
+ mic_dma_mmio_write(ch, dcr, MIC_DMA_SBOX_BASE + MIC_DMA_SBOX_DCR);
+}
+
+static void mic_dma_chan_set_desc_ring(struct mic_dma_chan *ch)
+{
+ u32 drar_hi;
+ dma_addr_t desc_ring_micpa = ch->desc_ring_micpa;
+
+ drar_hi = (MIC_DMA_DESC_RX_SIZE & 0x1ffff) << 4;
+ if (MIC_DMA_CHAN_MIC == ch->owner) {
+ drar_hi |= (desc_ring_micpa >> 32) & 0xf;
+ } else {
+ drar_hi |= MIC_DMA_SBOX_DRARHI_SYS_MASK;
+ drar_hi |= ((desc_ring_micpa >> 34)
+ & 0x1f) << 21;
+ drar_hi |= (desc_ring_micpa >> 32) & 0x3;
+ }
+ mic_dma_write_reg(ch, MIC_DMA_REG_DRAR_LO, (u32) desc_ring_micpa);
+ mic_dma_write_reg(ch, MIC_DMA_REG_DRAR_HI, drar_hi);
+}
+
+static inline void mic_dma_chan_mask_intr(struct mic_dma_chan *ch)
+{
+ u32 dcar = mic_dma_read_reg(ch, MIC_DMA_REG_DCAR);
+
+ if (MIC_DMA_CHAN_MIC == ch->owner)
+ dcar |= MIC_DMA_SBOX_DCAR_IM0;
+ else
+ dcar |= MIC_DMA_SBOX_DCAR_IM1;
+ mic_dma_write_reg(ch, MIC_DMA_REG_DCAR, dcar);
+}
+
+static inline void mic_dma_chan_unmask_intr(struct mic_dma_chan *ch)
+{
+ u32 dcar = mic_dma_read_reg(ch, MIC_DMA_REG_DCAR);
+
+ if (MIC_DMA_CHAN_MIC == ch->owner)
+ dcar &= ~MIC_DMA_SBOX_DCAR_IM0;
+ else
+ dcar &= ~MIC_DMA_SBOX_DCAR_IM1;
+ mic_dma_write_reg(ch, MIC_DMA_REG_DCAR, dcar);
+}
+
+static void mic_dma_ack_interrupt(struct mic_dma_chan *ch)
+{
+ if (MIC_DMA_CHAN_MIC == ch->owner) {
+ /* HW errata */
+ mic_dma_chan_mask_intr(ch);
+ mic_dma_chan_unmask_intr(ch);
+ }
+ to_mbus_hw_ops(ch)->ack_interrupt(to_mbus_device(ch), ch->ch_num);
+}
+#endif