diff options
Diffstat (limited to 'drivers/dma/mv_xor.c')
| -rw-r--r-- | drivers/dma/mv_xor.c | 1474 |
1 files changed, 1474 insertions, 0 deletions
diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c new file mode 100644 index 000000000..abc8d3e04 --- /dev/null +++ b/drivers/dma/mv_xor.c @@ -0,0 +1,1474 @@ +/* + * offload engine driver for the Marvell XOR engine + * Copyright (C) 2007, 2008, Marvell International Ltd. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope 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. + */ + +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/delay.h> +#include <linux/dma-mapping.h> +#include <linux/spinlock.h> +#include <linux/interrupt.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/memory.h> +#include <linux/clk.h> +#include <linux/of.h> +#include <linux/of_irq.h> +#include <linux/irqdomain.h> +#include <linux/cpumask.h> +#include <linux/platform_data/dma-mv_xor.h> + +#include "dmaengine.h" +#include "mv_xor.h" + +enum mv_xor_type { + XOR_ORION, + XOR_ARMADA_38X, + XOR_ARMADA_37XX, +}; + +enum mv_xor_mode { + XOR_MODE_IN_REG, + XOR_MODE_IN_DESC, +}; + +static void mv_xor_issue_pending(struct dma_chan *chan); + +#define to_mv_xor_chan(chan) \ + container_of(chan, struct mv_xor_chan, dmachan) + +#define to_mv_xor_slot(tx) \ + container_of(tx, struct mv_xor_desc_slot, async_tx) + +#define mv_chan_to_devp(chan) \ + ((chan)->dmadev.dev) + +static void mv_desc_init(struct mv_xor_desc_slot *desc, + dma_addr_t addr, u32 byte_count, + enum dma_ctrl_flags flags) +{ + struct mv_xor_desc *hw_desc = desc->hw_desc; + + hw_desc->status = XOR_DESC_DMA_OWNED; + hw_desc->phy_next_desc = 0; + /* Enable end-of-descriptor interrupts only for DMA_PREP_INTERRUPT */ + hw_desc->desc_command = (flags & DMA_PREP_INTERRUPT) ? + XOR_DESC_EOD_INT_EN : 0; + hw_desc->phy_dest_addr = addr; + hw_desc->byte_count = byte_count; +} + +static void mv_desc_set_mode(struct mv_xor_desc_slot *desc) +{ + struct mv_xor_desc *hw_desc = desc->hw_desc; + + switch (desc->type) { + case DMA_XOR: + case DMA_INTERRUPT: + hw_desc->desc_command |= XOR_DESC_OPERATION_XOR; + break; + case DMA_MEMCPY: + hw_desc->desc_command |= XOR_DESC_OPERATION_MEMCPY; + break; + default: + BUG(); + return; + } +} + +static void mv_desc_set_next_desc(struct mv_xor_desc_slot *desc, + u32 next_desc_addr) +{ + struct mv_xor_desc *hw_desc = desc->hw_desc; + BUG_ON(hw_desc->phy_next_desc); + hw_desc->phy_next_desc = next_desc_addr; +} + +static void mv_desc_set_src_addr(struct mv_xor_desc_slot *desc, + int index, dma_addr_t addr) +{ + struct mv_xor_desc *hw_desc = desc->hw_desc; + hw_desc->phy_src_addr[mv_phy_src_idx(index)] = addr; + if (desc->type == DMA_XOR) + hw_desc->desc_command |= (1 << index); +} + +static u32 mv_chan_get_current_desc(struct mv_xor_chan *chan) +{ + return readl_relaxed(XOR_CURR_DESC(chan)); +} + +static void mv_chan_set_next_descriptor(struct mv_xor_chan *chan, + u32 next_desc_addr) +{ + writel_relaxed(next_desc_addr, XOR_NEXT_DESC(chan)); +} + +static void mv_chan_unmask_interrupts(struct mv_xor_chan *chan) +{ + u32 val = readl_relaxed(XOR_INTR_MASK(chan)); + val |= XOR_INTR_MASK_VALUE << (chan->idx * 16); + writel_relaxed(val, XOR_INTR_MASK(chan)); +} + +static u32 mv_chan_get_intr_cause(struct mv_xor_chan *chan) +{ + u32 intr_cause = readl_relaxed(XOR_INTR_CAUSE(chan)); + intr_cause = (intr_cause >> (chan->idx * 16)) & 0xFFFF; + return intr_cause; +} + +static void mv_chan_clear_eoc_cause(struct mv_xor_chan *chan) +{ + u32 val; + + val = XOR_INT_END_OF_DESC | XOR_INT_END_OF_CHAIN | XOR_INT_STOPPED; + val = ~(val << (chan->idx * 16)); + dev_dbg(mv_chan_to_devp(chan), "%s, val 0x%08x\n", __func__, val); + writel_relaxed(val, XOR_INTR_CAUSE(chan)); +} + +static void mv_chan_clear_err_status(struct mv_xor_chan *chan) +{ + u32 val = 0xFFFF0000 >> (chan->idx * 16); + writel_relaxed(val, XOR_INTR_CAUSE(chan)); +} + +static void mv_chan_set_mode(struct mv_xor_chan *chan, + u32 op_mode) +{ + u32 config = readl_relaxed(XOR_CONFIG(chan)); + + config &= ~0x7; + config |= op_mode; + +#if defined(__BIG_ENDIAN) + config |= XOR_DESCRIPTOR_SWAP; +#else + config &= ~XOR_DESCRIPTOR_SWAP; +#endif + + writel_relaxed(config, XOR_CONFIG(chan)); +} + +static void mv_chan_activate(struct mv_xor_chan *chan) +{ + dev_dbg(mv_chan_to_devp(chan), " activate chan.\n"); + + /* writel ensures all descriptors are flushed before activation */ + writel(BIT(0), XOR_ACTIVATION(chan)); +} + +static char mv_chan_is_busy(struct mv_xor_chan *chan) +{ + u32 state = readl_relaxed(XOR_ACTIVATION(chan)); + + state = (state >> 4) & 0x3; + + return (state == 1) ? 1 : 0; +} + +/* + * mv_chan_start_new_chain - program the engine to operate on new + * chain headed by sw_desc + * Caller must hold &mv_chan->lock while calling this function + */ +static void mv_chan_start_new_chain(struct mv_xor_chan *mv_chan, + struct mv_xor_desc_slot *sw_desc) +{ + dev_dbg(mv_chan_to_devp(mv_chan), "%s %d: sw_desc %p\n", + __func__, __LINE__, sw_desc); + + /* set the hardware chain */ + mv_chan_set_next_descriptor(mv_chan, sw_desc->async_tx.phys); + + mv_chan->pending++; + mv_xor_issue_pending(&mv_chan->dmachan); +} + +static dma_cookie_t +mv_desc_run_tx_complete_actions(struct mv_xor_desc_slot *desc, + struct mv_xor_chan *mv_chan, + dma_cookie_t cookie) +{ + BUG_ON(desc->async_tx.cookie < 0); + + if (desc->async_tx.cookie > 0) { + cookie = desc->async_tx.cookie; + + dma_descriptor_unmap(&desc->async_tx); + /* call the callback (must not sleep or submit new + * operations to this channel) + */ + dmaengine_desc_get_callback_invoke(&desc->async_tx, NULL); + } + + /* run dependent operations */ + dma_run_dependencies(&desc->async_tx); + + return cookie; +} + +static int +mv_chan_clean_completed_slots(struct mv_xor_chan *mv_chan) +{ + struct mv_xor_desc_slot *iter, *_iter; + + dev_dbg(mv_chan_to_devp(mv_chan), "%s %d\n", __func__, __LINE__); + list_for_each_entry_safe(iter, _iter, &mv_chan->completed_slots, + node) { + + if (async_tx_test_ack(&iter->async_tx)) { + list_move_tail(&iter->node, &mv_chan->free_slots); + if (!list_empty(&iter->sg_tx_list)) { + list_splice_tail_init(&iter->sg_tx_list, + &mv_chan->free_slots); + } + } + } + return 0; +} + +static int +mv_desc_clean_slot(struct mv_xor_desc_slot *desc, + struct mv_xor_chan *mv_chan) +{ + dev_dbg(mv_chan_to_devp(mv_chan), "%s %d: desc %p flags %d\n", + __func__, __LINE__, desc, desc->async_tx.flags); + + /* the client is allowed to attach dependent operations + * until 'ack' is set + */ + if (!async_tx_test_ack(&desc->async_tx)) { + /* move this slot to the completed_slots */ + list_move_tail(&desc->node, &mv_chan->completed_slots); + if (!list_empty(&desc->sg_tx_list)) { + list_splice_tail_init(&desc->sg_tx_list, + &mv_chan->completed_slots); + } + } else { + list_move_tail(&desc->node, &mv_chan->free_slots); + if (!list_empty(&desc->sg_tx_list)) { + list_splice_tail_init(&desc->sg_tx_list, + &mv_chan->free_slots); + } + } + + return 0; +} + +/* This function must be called with the mv_xor_chan spinlock held */ +static void mv_chan_slot_cleanup(struct mv_xor_chan *mv_chan) +{ + struct mv_xor_desc_slot *iter, *_iter; + dma_cookie_t cookie = 0; + int busy = mv_chan_is_busy(mv_chan); + u32 current_desc = mv_chan_get_current_desc(mv_chan); + int current_cleaned = 0; + struct mv_xor_desc *hw_desc; + + dev_dbg(mv_chan_to_devp(mv_chan), "%s %d\n", __func__, __LINE__); + dev_dbg(mv_chan_to_devp(mv_chan), "current_desc %x\n", current_desc); + mv_chan_clean_completed_slots(mv_chan); + + /* free completed slots from the chain starting with + * the oldest descriptor + */ + + list_for_each_entry_safe(iter, _iter, &mv_chan->chain, + node) { + + /* clean finished descriptors */ + hw_desc = iter->hw_desc; + if (hw_desc->status & XOR_DESC_SUCCESS) { + cookie = mv_desc_run_tx_complete_actions(iter, mv_chan, + cookie); + + /* done processing desc, clean slot */ + mv_desc_clean_slot(iter, mv_chan); + + /* break if we did cleaned the current */ + if (iter->async_tx.phys == current_desc) { + current_cleaned = 1; + break; + } + } else { + if (iter->async_tx.phys == current_desc) { + current_cleaned = 0; + break; + } + } + } + + if ((busy == 0) && !list_empty(&mv_chan->chain)) { + if (current_cleaned) { + /* + * current descriptor cleaned and removed, run + * from list head + */ + iter = list_entry(mv_chan->chain.next, + struct mv_xor_desc_slot, + node); + mv_chan_start_new_chain(mv_chan, iter); + } else { + if (!list_is_last(&iter->node, &mv_chan->chain)) { + /* + * descriptors are still waiting after + * current, trigger them + */ + iter = list_entry(iter->node.next, + struct mv_xor_desc_slot, + node); + mv_chan_start_new_chain(mv_chan, iter); + } else { + /* + * some descriptors are still waiting + * to be cleaned + */ + tasklet_schedule(&mv_chan->irq_tasklet); + } + } + } + + if (cookie > 0) + mv_chan->dmachan.completed_cookie = cookie; +} + +static void mv_xor_tasklet(unsigned long data) +{ + struct mv_xor_chan *chan = (struct mv_xor_chan *) data; + + spin_lock_bh(&chan->lock); + mv_chan_slot_cleanup(chan); + spin_unlock_bh(&chan->lock); +} + +static struct mv_xor_desc_slot * +mv_chan_alloc_slot(struct mv_xor_chan *mv_chan) +{ + struct mv_xor_desc_slot *iter; + + spin_lock_bh(&mv_chan->lock); + + if (!list_empty(&mv_chan->free_slots)) { + iter = list_first_entry(&mv_chan->free_slots, + struct mv_xor_desc_slot, + node); + + list_move_tail(&iter->node, &mv_chan->allocated_slots); + + spin_unlock_bh(&mv_chan->lock); + + /* pre-ack descriptor */ + async_tx_ack(&iter->async_tx); + iter->async_tx.cookie = -EBUSY; + + return iter; + + } + + spin_unlock_bh(&mv_chan->lock); + + /* try to free some slots if the allocation fails */ + tasklet_schedule(&mv_chan->irq_tasklet); + + return NULL; +} + +/************************ DMA engine API functions ****************************/ +static dma_cookie_t +mv_xor_tx_submit(struct dma_async_tx_descriptor *tx) +{ + struct mv_xor_desc_slot *sw_desc = to_mv_xor_slot(tx); + struct mv_xor_chan *mv_chan = to_mv_xor_chan(tx->chan); + struct mv_xor_desc_slot *old_chain_tail; + dma_cookie_t cookie; + int new_hw_chain = 1; + + dev_dbg(mv_chan_to_devp(mv_chan), + "%s sw_desc %p: async_tx %p\n", + __func__, sw_desc, &sw_desc->async_tx); + + spin_lock_bh(&mv_chan->lock); + cookie = dma_cookie_assign(tx); + + if (list_empty(&mv_chan->chain)) + list_move_tail(&sw_desc->node, &mv_chan->chain); + else { + new_hw_chain = 0; + + old_chain_tail = list_entry(mv_chan->chain.prev, + struct mv_xor_desc_slot, + node); + list_move_tail(&sw_desc->node, &mv_chan->chain); + + dev_dbg(mv_chan_to_devp(mv_chan), "Append to last desc %pa\n", + &old_chain_tail->async_tx.phys); + + /* fix up the hardware chain */ + mv_desc_set_next_desc(old_chain_tail, sw_desc->async_tx.phys); + + /* if the channel is not busy */ + if (!mv_chan_is_busy(mv_chan)) { + u32 current_desc = mv_chan_get_current_desc(mv_chan); + /* + * and the curren desc is the end of the chain before + * the append, then we need to start the channel + */ + if (current_desc == old_chain_tail->async_tx.phys) + new_hw_chain = 1; + } + } + + if (new_hw_chain) + mv_chan_start_new_chain(mv_chan, sw_desc); + + spin_unlock_bh(&mv_chan->lock); + + return cookie; +} + +/* returns the number of allocated descriptors */ +static int mv_xor_alloc_chan_resources(struct dma_chan *chan) +{ + void *virt_desc; + dma_addr_t dma_desc; + int idx; + struct mv_xor_chan *mv_chan = to_mv_xor_chan(chan); + struct mv_xor_desc_slot *slot = NULL; + int num_descs_in_pool = MV_XOR_POOL_SIZE/MV_XOR_SLOT_SIZE; + + /* Allocate descriptor slots */ + idx = mv_chan->slots_allocated; + while (idx < num_descs_in_pool) { + slot = kzalloc(sizeof(*slot), GFP_KERNEL); + if (!slot) { + dev_info(mv_chan_to_devp(mv_chan), + "channel only initialized %d descriptor slots", + idx); + break; + } + virt_desc = mv_chan->dma_desc_pool_virt; + slot->hw_desc = virt_desc + idx * MV_XOR_SLOT_SIZE; + + dma_async_tx_descriptor_init(&slot->async_tx, chan); + slot->async_tx.tx_submit = mv_xor_tx_submit; + INIT_LIST_HEAD(&slot->node); + INIT_LIST_HEAD(&slot->sg_tx_list); + dma_desc = mv_chan->dma_desc_pool; + slot->async_tx.phys = dma_desc + idx * MV_XOR_SLOT_SIZE; + slot->idx = idx++; + + spin_lock_bh(&mv_chan->lock); + mv_chan->slots_allocated = idx; + list_add_tail(&slot->node, &mv_chan->free_slots); + spin_unlock_bh(&mv_chan->lock); + } + + dev_dbg(mv_chan_to_devp(mv_chan), + "allocated %d descriptor slots\n", + mv_chan->slots_allocated); + + return mv_chan->slots_allocated ? : -ENOMEM; +} + +/* + * Check if source or destination is an PCIe/IO address (non-SDRAM) and add + * a new MBus window if necessary. Use a cache for these check so that + * the MMIO mapped registers don't have to be accessed for this check + * to speed up this process. + */ +static int mv_xor_add_io_win(struct mv_xor_chan *mv_chan, u32 addr) +{ + struct mv_xor_device *xordev = mv_chan->xordev; + void __iomem *base = mv_chan->mmr_high_base; + u32 win_enable; + u32 size; + u8 target, attr; + int ret; + int i; + + /* Nothing needs to get done for the Armada 3700 */ + if (xordev->xor_type == XOR_ARMADA_37XX) + return 0; + + /* + * Loop over the cached windows to check, if the requested area + * is already mapped. If this the case, nothing needs to be done + * and we can return. + */ + for (i = 0; i < WINDOW_COUNT; i++) { + if (addr >= xordev->win_start[i] && + addr <= xordev->win_end[i]) { + /* Window is already mapped */ + return 0; + } + } + + /* + * The window is not mapped, so we need to create the new mapping + */ + + /* If no IO window is found that addr has to be located in SDRAM */ + ret = mvebu_mbus_get_io_win_info(addr, &size, &target, &attr); + if (ret < 0) + return 0; + + /* + * Mask the base addr 'addr' according to 'size' read back from the + * MBus window. Otherwise we might end up with an address located + * somewhere in the middle of this area here. + */ + size -= 1; + addr &= ~size; + + /* + * Reading one of both enabled register is enough, as they are always + * programmed to the identical values + */ + win_enable = readl(base + WINDOW_BAR_ENABLE(0)); + + /* Set 'i' to the first free window to write the new values to */ + i = ffs(~win_enable) - 1; + if (i >= WINDOW_COUNT) + return -ENOMEM; + + writel((addr & 0xffff0000) | (attr << 8) | target, + base + WINDOW_BASE(i)); + writel(size & 0xffff0000, base + WINDOW_SIZE(i)); + + /* Fill the caching variables for later use */ + xordev->win_start[i] = addr; + xordev->win_end[i] = addr + size; + + win_enable |= (1 << i); + win_enable |= 3 << (16 + (2 * i)); + writel(win_enable, base + WINDOW_BAR_ENABLE(0)); + writel(win_enable, base + WINDOW_BAR_ENABLE(1)); + + return 0; +} + +static struct dma_async_tx_descriptor * +mv_xor_prep_dma_xor(struct dma_chan *chan, dma_addr_t dest, dma_addr_t *src, + unsigned int src_cnt, size_t len, unsigned long flags) +{ + struct mv_xor_chan *mv_chan = to_mv_xor_chan(chan); + struct mv_xor_desc_slot *sw_desc; + int ret; + + if (unlikely(len < MV_XOR_MIN_BYTE_COUNT)) + return NULL; + + BUG_ON(len > MV_XOR_MAX_BYTE_COUNT); + + dev_dbg(mv_chan_to_devp(mv_chan), + "%s src_cnt: %d len: %zu dest %pad flags: %ld\n", + __func__, src_cnt, len, &dest, flags); + + /* Check if a new window needs to get added for 'dest' */ + ret = mv_xor_add_io_win(mv_chan, dest); + if (ret) + return NULL; + + sw_desc = mv_chan_alloc_slot(mv_chan); + if (sw_desc) { + sw_desc->type = DMA_XOR; + sw_desc->async_tx.flags = flags; + mv_desc_init(sw_desc, dest, len, flags); + if (mv_chan->op_in_desc == XOR_MODE_IN_DESC) + mv_desc_set_mode(sw_desc); + while (src_cnt--) { + /* Check if a new window needs to get added for 'src' */ + ret = mv_xor_add_io_win(mv_chan, src[src_cnt]); + if (ret) + return NULL; + mv_desc_set_src_addr(sw_desc, src_cnt, src[src_cnt]); + } + } + + dev_dbg(mv_chan_to_devp(mv_chan), + "%s sw_desc %p async_tx %p \n", + __func__, sw_desc, &sw_desc->async_tx); + return sw_desc ? &sw_desc->async_tx : NULL; +} + +static struct dma_async_tx_descriptor * +mv_xor_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, + size_t len, unsigned long flags) +{ + /* + * A MEMCPY operation is identical to an XOR operation with only + * a single source address. + */ + return mv_xor_prep_dma_xor(chan, dest, &src, 1, len, flags); +} + +static struct dma_async_tx_descriptor * +mv_xor_prep_dma_interrupt(struct dma_chan *chan, unsigned long flags) +{ + struct mv_xor_chan *mv_chan = to_mv_xor_chan(chan); + dma_addr_t src, dest; + size_t len; + + src = mv_chan->dummy_src_addr; + dest = mv_chan->dummy_dst_addr; + len = MV_XOR_MIN_BYTE_COUNT; + + /* + * We implement the DMA_INTERRUPT operation as a minimum sized + * XOR operation with a single dummy source address. + */ + return mv_xor_prep_dma_xor(chan, dest, &src, 1, len, flags); +} + +static void mv_xor_free_chan_resources(struct dma_chan *chan) +{ + struct mv_xor_chan *mv_chan = to_mv_xor_chan(chan); + struct mv_xor_desc_slot *iter, *_iter; + int in_use_descs = 0; + + spin_lock_bh(&mv_chan->lock); + + mv_chan_slot_cleanup(mv_chan); + + list_for_each_entry_safe(iter, _iter, &mv_chan->chain, + node) { + in_use_descs++; + list_move_tail(&iter->node, &mv_chan->free_slots); + } + list_for_each_entry_safe(iter, _iter, &mv_chan->completed_slots, + node) { + in_use_descs++; + list_move_tail(&iter->node, &mv_chan->free_slots); + } + list_for_each_entry_safe(iter, _iter, &mv_chan->allocated_slots, + node) { + in_use_descs++; + list_move_tail(&iter->node, &mv_chan->free_slots); + } + list_for_each_entry_safe_reverse( + iter, _iter, &mv_chan->free_slots, node) { + list_del(&iter->node); + kfree(iter); + mv_chan->slots_allocated--; + } + + dev_dbg(mv_chan_to_devp(mv_chan), "%s slots_allocated %d\n", + __func__, mv_chan->slots_allocated); + spin_unlock_bh(&mv_chan->lock); + + if (in_use_descs) + dev_err(mv_chan_to_devp(mv_chan), + "freeing %d in use descriptors!\n", in_use_descs); +} + +/** + * mv_xor_status - poll the status of an XOR transaction + * @chan: XOR channel handle + * @cookie: XOR transaction identifier + * @txstate: XOR transactions state holder (or NULL) + */ +static enum dma_status mv_xor_status(struct dma_chan *chan, + dma_cookie_t cookie, + struct dma_tx_state *txstate) +{ + struct mv_xor_chan *mv_chan = to_mv_xor_chan(chan); + enum dma_status ret; + + ret = dma_cookie_status(chan, cookie, txstate); + if (ret == DMA_COMPLETE) + return ret; + + spin_lock_bh(&mv_chan->lock); + mv_chan_slot_cleanup(mv_chan); + spin_unlock_bh(&mv_chan->lock); + + return dma_cookie_status(chan, cookie, txstate); +} + +static void mv_chan_dump_regs(struct mv_xor_chan *chan) +{ + u32 val; + + val = readl_relaxed(XOR_CONFIG(chan)); + dev_err(mv_chan_to_devp(chan), "config 0x%08x\n", val); + + val = readl_relaxed(XOR_ACTIVATION(chan)); + dev_err(mv_chan_to_devp(chan), "activation 0x%08x\n", val); + + val = readl_relaxed(XOR_INTR_CAUSE(chan)); + dev_err(mv_chan_to_devp(chan), "intr cause 0x%08x\n", val); + + val = readl_relaxed(XOR_INTR_MASK(chan)); + dev_err(mv_chan_to_devp(chan), "intr mask 0x%08x\n", val); + + val = readl_relaxed(XOR_ERROR_CAUSE(chan)); + dev_err(mv_chan_to_devp(chan), "error cause 0x%08x\n", val); + + val = readl_relaxed(XOR_ERROR_ADDR(chan)); + dev_err(mv_chan_to_devp(chan), "error addr 0x%08x\n", val); +} + +static void mv_chan_err_interrupt_handler(struct mv_xor_chan *chan, + u32 intr_cause) +{ + if (intr_cause & XOR_INT_ERR_DECODE) { + dev_dbg(mv_chan_to_devp(chan), "ignoring address decode error\n"); + return; + } + + dev_err(mv_chan_to_devp(chan), "error on chan %d. intr cause 0x%08x\n", + chan->idx, intr_cause); + + mv_chan_dump_regs(chan); + WARN_ON(1); +} + +static irqreturn_t mv_xor_interrupt_handler(int irq, void *data) +{ + struct mv_xor_chan *chan = data; + u32 intr_cause = mv_chan_get_intr_cause(chan); + + dev_dbg(mv_chan_to_devp(chan), "intr cause %x\n", intr_cause); + + if (intr_cause & XOR_INTR_ERRORS) + mv_chan_err_interrupt_handler(chan, intr_cause); + + tasklet_schedule(&chan->irq_tasklet); + + mv_chan_clear_eoc_cause(chan); + + return IRQ_HANDLED; +} + +static void mv_xor_issue_pending(struct dma_chan *chan) +{ + struct mv_xor_chan *mv_chan = to_mv_xor_chan(chan); + + if (mv_chan->pending >= MV_XOR_THRESHOLD) { + mv_chan->pending = 0; + mv_chan_activate(mv_chan); + } +} + +/* + * Perform a transaction to verify the HW works. + */ + +static int mv_chan_memcpy_self_test(struct mv_xor_chan *mv_chan) +{ + int i, ret; + void *src, *dest; + dma_addr_t src_dma, dest_dma; + struct dma_chan *dma_chan; + dma_cookie_t cookie; + struct dma_async_tx_descriptor *tx; + struct dmaengine_unmap_data *unmap; + int err = 0; + + src = kmalloc(PAGE_SIZE, GFP_KERNEL); + if (!src) + return -ENOMEM; + + dest = kzalloc(PAGE_SIZE, GFP_KERNEL); + if (!dest) { + kfree(src); + return -ENOMEM; + } + + /* Fill in src buffer */ + for (i = 0; i < PAGE_SIZE; i++) + ((u8 *) src)[i] = (u8)i; + + dma_chan = &mv_chan->dmachan; + if (mv_xor_alloc_chan_resources(dma_chan) < 1) { + err = -ENODEV; + goto out; + } + + unmap = dmaengine_get_unmap_data(dma_chan->device->dev, 2, GFP_KERNEL); + if (!unmap) { + err = -ENOMEM; + goto free_resources; + } + + src_dma = dma_map_page(dma_chan->device->dev, virt_to_page(src), + offset_in_page(src), PAGE_SIZE, + DMA_TO_DEVICE); + unmap->addr[0] = src_dma; + + ret = dma_mapping_error(dma_chan->device->dev, src_dma); + if (ret) { + err = -ENOMEM; + goto free_resources; + } + unmap->to_cnt = 1; + + dest_dma = dma_map_page(dma_chan->device->dev, virt_to_page(dest), + offset_in_page(dest), PAGE_SIZE, + DMA_FROM_DEVICE); + unmap->addr[1] = dest_dma; + + ret = dma_mapping_error(dma_chan->device->dev, dest_dma); + if (ret) { + err = -ENOMEM; + goto free_resources; + } + unmap->from_cnt = 1; + unmap->len = PAGE_SIZE; + + tx = mv_xor_prep_dma_memcpy(dma_chan, dest_dma, src_dma, + PAGE_SIZE, 0); + if (!tx) { + dev_err(dma_chan->device->dev, + "Self-test cannot prepare operation, disabling\n"); + err = -ENODEV; + goto free_resources; + } + + cookie = mv_xor_tx_submit(tx); + if (dma_submit_error(cookie)) { + dev_err(dma_chan->device->dev, + "Self-test submit error, disabling\n"); + err = -ENODEV; + goto free_resources; + } + + mv_xor_issue_pending(dma_chan); + async_tx_ack(tx); + msleep(1); + + if (mv_xor_status(dma_chan, cookie, NULL) != + DMA_COMPLETE) { + dev_err(dma_chan->device->dev, + "Self-test copy timed out, disabling\n"); + err = -ENODEV; + goto free_resources; + } + + dma_sync_single_for_cpu(dma_chan->device->dev, dest_dma, + PAGE_SIZE, DMA_FROM_DEVICE); + if (memcmp(src, dest, PAGE_SIZE)) { + dev_err(dma_chan->device->dev, + "Self-test copy failed compare, disabling\n"); + err = -ENODEV; + goto free_resources; + } + +free_resources: + dmaengine_unmap_put(unmap); + mv_xor_free_chan_resources(dma_chan); +out: + kfree(src); + kfree(dest); + return err; +} + +#define MV_XOR_NUM_SRC_TEST 4 /* must be <= 15 */ +static int +mv_chan_xor_self_test(struct mv_xor_chan *mv_chan) +{ + int i, src_idx, ret; + struct page *dest; + struct page *xor_srcs[MV_XOR_NUM_SRC_TEST]; + dma_addr_t dma_srcs[MV_XOR_NUM_SRC_TEST]; + dma_addr_t dest_dma; + struct dma_async_tx_descriptor *tx; + struct dmaengine_unmap_data *unmap; + struct dma_chan *dma_chan; + dma_cookie_t cookie; + u8 cmp_byte = 0; + u32 cmp_word; + int err = 0; + int src_count = MV_XOR_NUM_SRC_TEST; + + for (src_idx = 0; src_idx < src_count; src_idx++) { + xor_srcs[src_idx] = alloc_page(GFP_KERNEL); + if (!xor_srcs[src_idx]) { + while (src_idx--) + __free_page(xor_srcs[src_idx]); + return -ENOMEM; + } + } + + dest = alloc_page(GFP_KERNEL); + if (!dest) { + while (src_idx--) + __free_page(xor_srcs[src_idx]); + return -ENOMEM; + } + + /* Fill in src buffers */ + for (src_idx = 0; src_idx < src_count; src_idx++) { + u8 *ptr = page_address(xor_srcs[src_idx]); + for (i = 0; i < PAGE_SIZE; i++) + ptr[i] = (1 << src_idx); + } + + for (src_idx = 0; src_idx < src_count; src_idx++) + cmp_byte ^= (u8) (1 << src_idx); + + cmp_word = (cmp_byte << 24) | (cmp_byte << 16) | + (cmp_byte << 8) | cmp_byte; + + memset(page_address(dest), 0, PAGE_SIZE); + + dma_chan = &mv_chan->dmachan; + if (mv_xor_alloc_chan_resources(dma_chan) < 1) { + err = -ENODEV; + goto out; + } + + unmap = dmaengine_get_unmap_data(dma_chan->device->dev, src_count + 1, + GFP_KERNEL); + if (!unmap) { + err = -ENOMEM; + goto free_resources; + } + + /* test xor */ + for (i = 0; i < src_count; i++) { + unmap->addr[i] = dma_map_page(dma_chan->device->dev, xor_srcs[i], + 0, PAGE_SIZE, DMA_TO_DEVICE); + dma_srcs[i] = unmap->addr[i]; + ret = dma_mapping_error(dma_chan->device->dev, unmap->addr[i]); + if (ret) { + err = -ENOMEM; + goto free_resources; + } + unmap->to_cnt++; + } + + unmap->addr[src_count] = dma_map_page(dma_chan->device->dev, dest, 0, PAGE_SIZE, + DMA_FROM_DEVICE); + dest_dma = unmap->addr[src_count]; + ret = dma_mapping_error(dma_chan->device->dev, unmap->addr[src_count]); + if (ret) { + err = -ENOMEM; + goto free_resources; + } + unmap->from_cnt = 1; + unmap->len = PAGE_SIZE; + + tx = mv_xor_prep_dma_xor(dma_chan, dest_dma, dma_srcs, + src_count, PAGE_SIZE, 0); + if (!tx) { + dev_err(dma_chan->device->dev, + "Self-test cannot prepare operation, disabling\n"); + err = -ENODEV; + goto free_resources; + } + + cookie = mv_xor_tx_submit(tx); + if (dma_submit_error(cookie)) { + dev_err(dma_chan->device->dev, + "Self-test submit error, disabling\n"); + err = -ENODEV; + goto free_resources; + } + + mv_xor_issue_pending(dma_chan); + async_tx_ack(tx); + msleep(8); + + if (mv_xor_status(dma_chan, cookie, NULL) != + DMA_COMPLETE) { + dev_err(dma_chan->device->dev, + "Self-test xor timed out, disabling\n"); + err = -ENODEV; + goto free_resources; + } + + dma_sync_single_for_cpu(dma_chan->device->dev, dest_dma, + PAGE_SIZE, DMA_FROM_DEVICE); + for (i = 0; i < (PAGE_SIZE / sizeof(u32)); i++) { + u32 *ptr = page_address(dest); + if (ptr[i] != cmp_word) { + dev_err(dma_chan->device->dev, + "Self-test xor failed compare, disabling. index %d, data %x, expected %x\n", + i, ptr[i], cmp_word); + err = -ENODEV; + goto free_resources; + } + } + +free_resources: + dmaengine_unmap_put(unmap); + mv_xor_free_chan_resources(dma_chan); +out: + src_idx = src_count; + while (src_idx--) + __free_page(xor_srcs[src_idx]); + __free_page(dest); + return err; +} + +static int mv_xor_channel_remove(struct mv_xor_chan *mv_chan) +{ + struct dma_chan *chan, *_chan; + struct device *dev = mv_chan->dmadev.dev; + + dma_async_device_unregister(&mv_chan->dmadev); + + dma_free_coherent(dev, MV_XOR_POOL_SIZE, + mv_chan->dma_desc_pool_virt, mv_chan->dma_desc_pool); + dma_unmap_single(dev, mv_chan->dummy_src_addr, + MV_XOR_MIN_BYTE_COUNT, DMA_FROM_DEVICE); + dma_unmap_single(dev, mv_chan->dummy_dst_addr, + MV_XOR_MIN_BYTE_COUNT, DMA_TO_DEVICE); + + list_for_each_entry_safe(chan, _chan, &mv_chan->dmadev.channels, + device_node) { + list_del(&chan->device_node); + } + + free_irq(mv_chan->irq, mv_chan); + + return 0; +} + +static struct mv_xor_chan * +mv_xor_channel_add(struct mv_xor_device *xordev, + struct platform_device *pdev, + int idx, dma_cap_mask_t cap_mask, int irq) +{ + int ret = 0; + struct mv_xor_chan *mv_chan; + struct dma_device *dma_dev; + + mv_chan = devm_kzalloc(&pdev->dev, sizeof(*mv_chan), GFP_KERNEL); + if (!mv_chan) + return ERR_PTR(-ENOMEM); + + mv_chan->idx = idx; + mv_chan->irq = irq; + if (xordev->xor_type == XOR_ORION) + mv_chan->op_in_desc = XOR_MODE_IN_REG; + else + mv_chan->op_in_desc = XOR_MODE_IN_DESC; + + dma_dev = &mv_chan->dmadev; + dma_dev->dev = &pdev->dev; + mv_chan->xordev = xordev; + + /* + * These source and destination dummy buffers are used to implement + * a DMA_INTERRUPT operation as a minimum-sized XOR operation. + * Hence, we only need to map the buffers at initialization-time. + */ + mv_chan->dummy_src_addr = dma_map_single(dma_dev->dev, + mv_chan->dummy_src, MV_XOR_MIN_BYTE_COUNT, DMA_FROM_DEVICE); + mv_chan->dummy_dst_addr = dma_map_single(dma_dev->dev, + mv_chan->dummy_dst, MV_XOR_MIN_BYTE_COUNT, DMA_TO_DEVICE); + + /* allocate coherent memory for hardware descriptors + * note: writecombine gives slightly better performance, but + * requires that we explicitly flush the writes + */ + mv_chan->dma_desc_pool_virt = + dma_alloc_wc(&pdev->dev, MV_XOR_POOL_SIZE, &mv_chan->dma_desc_pool, + GFP_KERNEL); + if (!mv_chan->dma_desc_pool_virt) + return ERR_PTR(-ENOMEM); + + /* discover transaction capabilites from the platform data */ + dma_dev->cap_mask = cap_mask; + + INIT_LIST_HEAD(&dma_dev->channels); + + /* set base routines */ + dma_dev->device_alloc_chan_resources = mv_xor_alloc_chan_resources; + dma_dev->device_free_chan_resources = mv_xor_free_chan_resources; + dma_dev->device_tx_status = mv_xor_status; + dma_dev->device_issue_pending = mv_xor_issue_pending; + + /* set prep routines based on capability */ + if (dma_has_cap(DMA_INTERRUPT, dma_dev->cap_mask)) + dma_dev->device_prep_dma_interrupt = mv_xor_prep_dma_interrupt; + if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) + dma_dev->device_prep_dma_memcpy = mv_xor_prep_dma_memcpy; + if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) { + dma_dev->max_xor = 8; + dma_dev->device_prep_dma_xor = mv_xor_prep_dma_xor; + } + + mv_chan->mmr_base = xordev->xor_base; + mv_chan->mmr_high_base = xordev->xor_high_base; + tasklet_init(&mv_chan->irq_tasklet, mv_xor_tasklet, (unsigned long) + mv_chan); + + /* clear errors before enabling interrupts */ + mv_chan_clear_err_status(mv_chan); + + ret = request_irq(mv_chan->irq, mv_xor_interrupt_handler, + 0, dev_name(&pdev->dev), mv_chan); + if (ret) + goto err_free_dma; + + mv_chan_unmask_interrupts(mv_chan); + + if (mv_chan->op_in_desc == XOR_MODE_IN_DESC) + mv_chan_set_mode(mv_chan, XOR_OPERATION_MODE_IN_DESC); + else + mv_chan_set_mode(mv_chan, XOR_OPERATION_MODE_XOR); + + spin_lock_init(&mv_chan->lock); + INIT_LIST_HEAD(&mv_chan->chain); + INIT_LIST_HEAD(&mv_chan->completed_slots); + INIT_LIST_HEAD(&mv_chan->free_slots); + INIT_LIST_HEAD(&mv_chan->allocated_slots); + mv_chan->dmachan.device = dma_dev; + dma_cookie_init(&mv_chan->dmachan); + + list_add_tail(&mv_chan->dmachan.device_node, &dma_dev->channels); + + if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) { + ret = mv_chan_memcpy_self_test(mv_chan); + dev_dbg(&pdev->dev, "memcpy self test returned %d\n", ret); + if (ret) + goto err_free_irq; + } + + if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) { + ret = mv_chan_xor_self_test(mv_chan); + dev_dbg(&pdev->dev, "xor self test returned %d\n", ret); + if (ret) + goto err_free_irq; + } + + dev_info(&pdev->dev, "Marvell XOR (%s): ( %s%s%s)\n", + mv_chan->op_in_desc ? "Descriptor Mode" : "Registers Mode", + dma_has_cap(DMA_XOR, dma_dev->cap_mask) ? "xor " : "", + dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask) ? "cpy " : "", + dma_has_cap(DMA_INTERRUPT, dma_dev->cap_mask) ? "intr " : ""); + + dma_async_device_register(dma_dev); + return mv_chan; + +err_free_irq: + free_irq(mv_chan->irq, mv_chan); +err_free_dma: + dma_free_coherent(&pdev->dev, MV_XOR_POOL_SIZE, + mv_chan->dma_desc_pool_virt, mv_chan->dma_desc_pool); + return ERR_PTR(ret); +} + +static void +mv_xor_conf_mbus_windows(struct mv_xor_device *xordev, + const struct mbus_dram_target_info *dram) +{ + void __iomem *base = xordev->xor_high_base; + u32 win_enable = 0; + int i; + + for (i = 0; i < 8; i++) { + writel(0, base + WINDOW_BASE(i)); + writel(0, base + WINDOW_SIZE(i)); + if (i < 4) + writel(0, base + WINDOW_REMAP_HIGH(i)); + } + + for (i = 0; i < dram->num_cs; i++) { + const struct mbus_dram_window *cs = dram->cs + i; + + writel((cs->base & 0xffff0000) | + (cs->mbus_attr << 8) | + dram->mbus_dram_target_id, base + WINDOW_BASE(i)); + writel((cs->size - 1) & 0xffff0000, base + WINDOW_SIZE(i)); + + /* Fill the caching variables for later use */ + xordev->win_start[i] = cs->base; + xordev->win_end[i] = cs->base + cs->size - 1; + + win_enable |= (1 << i); + win_enable |= 3 << (16 + (2 * i)); + } + + writel(win_enable, base + WINDOW_BAR_ENABLE(0)); + writel(win_enable, base + WINDOW_BAR_ENABLE(1)); + writel(0, base + WINDOW_OVERRIDE_CTRL(0)); + writel(0, base + WINDOW_OVERRIDE_CTRL(1)); +} + +static void +mv_xor_conf_mbus_windows_a3700(struct mv_xor_device *xordev) +{ + void __iomem *base = xordev->xor_high_base; + u32 win_enable = 0; + int i; + + for (i = 0; i < 8; i++) { + writel(0, base + WINDOW_BASE(i)); + writel(0, base + WINDOW_SIZE(i)); + if (i < 4) + writel(0, base + WINDOW_REMAP_HIGH(i)); + } + /* + * For Armada3700 open default 4GB Mbus window. The dram + * related configuration are done at AXIS level. + */ + writel(0xffff0000, base + WINDOW_SIZE(0)); + win_enable |= 1; + win_enable |= 3 << 16; + + writel(win_enable, base + WINDOW_BAR_ENABLE(0)); + writel(win_enable, base + WINDOW_BAR_ENABLE(1)); + writel(0, base + WINDOW_OVERRIDE_CTRL(0)); + writel(0, base + WINDOW_OVERRIDE_CTRL(1)); +} + +/* + * Since this XOR driver is basically used only for RAID5, we don't + * need to care about synchronizing ->suspend with DMA activity, + * because the DMA engine will naturally be quiet due to the block + * devices being suspended. + */ +static int mv_xor_suspend(struct platform_device *pdev, pm_message_t state) +{ + struct mv_xor_device *xordev = platform_get_drvdata(pdev); + int i; + + for (i = 0; i < MV_XOR_MAX_CHANNELS; i++) { + struct mv_xor_chan *mv_chan = xordev->channels[i]; + + if (!mv_chan) + continue; + + mv_chan->saved_config_reg = + readl_relaxed(XOR_CONFIG(mv_chan)); + mv_chan->saved_int_mask_reg = + readl_relaxed(XOR_INTR_MASK(mv_chan)); + } + + return 0; +} + +static int mv_xor_resume(struct platform_device *dev) +{ + struct mv_xor_device *xordev = platform_get_drvdata(dev); + const struct mbus_dram_target_info *dram; + int i; + + for (i = 0; i < MV_XOR_MAX_CHANNELS; i++) { + struct mv_xor_chan *mv_chan = xordev->channels[i]; + + if (!mv_chan) + continue; + + writel_relaxed(mv_chan->saved_config_reg, + XOR_CONFIG(mv_chan)); + writel_relaxed(mv_chan->saved_int_mask_reg, + XOR_INTR_MASK(mv_chan)); + } + + if (xordev->xor_type == XOR_ARMADA_37XX) { + mv_xor_conf_mbus_windows_a3700(xordev); + return 0; + } + + dram = mv_mbus_dram_info(); + if (dram) + mv_xor_conf_mbus_windows(xordev, dram); + + return 0; +} + +static const struct of_device_id mv_xor_dt_ids[] = { + { .compatible = "marvell,orion-xor", .data = (void *)XOR_ORION }, + { .compatible = "marvell,armada-380-xor", .data = (void *)XOR_ARMADA_38X }, + { .compatible = "marvell,armada-3700-xor", .data = (void *)XOR_ARMADA_37XX }, + {}, +}; + +static unsigned int mv_xor_engine_count; + +static int mv_xor_probe(struct platform_device *pdev) +{ + const struct mbus_dram_target_info *dram; + struct mv_xor_device *xordev; + struct mv_xor_platform_data *pdata = dev_get_platdata(&pdev->dev); + struct resource *res; + unsigned int max_engines, max_channels; + int i, ret; + + dev_notice(&pdev->dev, "Marvell shared XOR driver\n"); + + xordev = devm_kzalloc(&pdev->dev, sizeof(*xordev), GFP_KERNEL); + if (!xordev) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + return -ENODEV; + + xordev->xor_base = devm_ioremap(&pdev->dev, res->start, + resource_size(res)); + if (!xordev->xor_base) + return -EBUSY; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 1); + if (!res) + return -ENODEV; + + xordev->xor_high_base = devm_ioremap(&pdev->dev, res->start, + resource_size(res)); + if (!xordev->xor_high_base) + return -EBUSY; + + platform_set_drvdata(pdev, xordev); + + + /* + * We need to know which type of XOR device we use before + * setting up. In non-dt case it can only be the legacy one. + */ + xordev->xor_type = XOR_ORION; + if (pdev->dev.of_node) { + const struct of_device_id *of_id = + of_match_device(mv_xor_dt_ids, + &pdev->dev); + + xordev->xor_type = (uintptr_t)of_id->data; + } + + /* + * (Re-)program MBUS remapping windows if we are asked to. + */ + if (xordev->xor_type == XOR_ARMADA_37XX) { + mv_xor_conf_mbus_windows_a3700(xordev); + } else { + dram = mv_mbus_dram_info(); + if (dram) + mv_xor_conf_mbus_windows(xordev, dram); + } + + /* Not all platforms can gate the clock, so it is not + * an error if the clock does not exists. + */ + xordev->clk = clk_get(&pdev->dev, NULL); + if (!IS_ERR(xordev->clk)) + clk_prepare_enable(xordev->clk); + + /* + * We don't want to have more than one channel per CPU in + * order for async_tx to perform well. So we limit the number + * of engines and channels so that we take into account this + * constraint. Note that we also want to use channels from + * separate engines when possible. For dual-CPU Armada 3700 + * SoC with single XOR engine allow using its both channels. + */ + max_engines = num_present_cpus(); + if (xordev->xor_type == XOR_ARMADA_37XX) + max_channels = num_present_cpus(); + else + max_channels = min_t(unsigned int, + MV_XOR_MAX_CHANNELS, + DIV_ROUND_UP(num_present_cpus(), 2)); + + if (mv_xor_engine_count >= max_engines) + return 0; + + if (pdev->dev.of_node) { + struct device_node *np; + int i = 0; + + for_each_child_of_node(pdev->dev.of_node, np) { + struct mv_xor_chan *chan; + dma_cap_mask_t cap_mask; + int irq; + + if (i >= max_channels) + continue; + + dma_cap_zero(cap_mask); + dma_cap_set(DMA_MEMCPY, cap_mask); + dma_cap_set(DMA_XOR, cap_mask); + dma_cap_set(DMA_INTERRUPT, cap_mask); + + irq = irq_of_parse_and_map(np, 0); + if (!irq) { + ret = -ENODEV; + goto err_channel_add; + } + + chan = mv_xor_channel_add(xordev, pdev, i, + cap_mask, irq); + if (IS_ERR(chan)) { + ret = PTR_ERR(chan); + irq_dispose_mapping(irq); + goto err_channel_add; + } + + xordev->channels[i] = chan; + i++; + } + } else if (pdata && pdata->channels) { + for (i = 0; i < max_channels; i++) { + struct mv_xor_channel_data *cd; + struct mv_xor_chan *chan; + int irq; + + cd = &pdata->channels[i]; + irq = platform_get_irq(pdev, i); + if (irq < 0) { + ret = irq; + goto err_channel_add; + } + + chan = mv_xor_channel_add(xordev, pdev, i, + cd->cap_mask, irq); + if (IS_ERR(chan)) { + ret = PTR_ERR(chan); + goto err_channel_add; + } + + xordev->channels[i] = chan; + } + } + + return 0; + +err_channel_add: + for (i = 0; i < MV_XOR_MAX_CHANNELS; i++) + if (xordev->channels[i]) { + mv_xor_channel_remove(xordev->channels[i]); + if (pdev->dev.of_node) + irq_dispose_mapping(xordev->channels[i]->irq); + } + + if (!IS_ERR(xordev->clk)) { + clk_disable_unprepare(xordev->clk); + clk_put(xordev->clk); + } + + return ret; +} + +static struct platform_driver mv_xor_driver = { + .probe = mv_xor_probe, + .suspend = mv_xor_suspend, + .resume = mv_xor_resume, + .driver = { + .name = MV_XOR_NAME, + .of_match_table = of_match_ptr(mv_xor_dt_ids), + }, +}; + +builtin_platform_driver(mv_xor_driver); + +/* +MODULE_AUTHOR("Saeed Bishara <saeed@marvell.com>"); +MODULE_DESCRIPTION("DMA engine driver for Marvell's XOR engine"); +MODULE_LICENSE("GPL"); +*/ |