diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig index 1eca7b9760e6..7c8b8c41f4f4 100644 --- a/drivers/dma/Kconfig +++ b/drivers/dma/Kconfig @@ -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 + . + config INTEL_MID_DMAC tristate "Intel MID DMA support for Peripheral DMA controllers" depends on PCI && X86 diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile index c779e1eb2db2..bd9e7fa928bd 100644 --- a/drivers/dma/Makefile +++ b/drivers/dma/Makefile @@ -47,3 +47,4 @@ obj-$(CONFIG_MOXART_DMA) += moxart-dma.o obj-$(CONFIG_FSL_EDMA) += fsl-edma.o obj-$(CONFIG_QCOM_BAM_DMA) += qcom_bam_dma.o obj-y += xilinx/ +obj-$(CONFIG_INTEL_MIC_X100_DMA) += mic_x100_dma.o diff --git a/drivers/dma/mic_x100_dma.c b/drivers/dma/mic_x100_dma.c new file mode 100644 index 000000000000..6de2e677be04 --- /dev/null +++ b/drivers/dma/mic_x100_dma.c @@ -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 +#include +#include + +#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); + dev_set_drvdata(&mbdev->dev, 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 = dev_get_drvdata(&mbdev->dev); + 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"); diff --git a/drivers/dma/mic_x100_dma.h b/drivers/dma/mic_x100_dma.h new file mode 100644 index 000000000000..f663b0bdd11d --- /dev/null +++ b/drivers/dma/mic_x100_dma.h @@ -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 +#include +#include +#include +#include +#include +#include + +#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